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Cai Z, Wang Y, You Y, Yang N, Lu S, Xue J, Xing X, Sha S, Zhao L. Introduction of Cellulolytic Bacterium Bacillus velezensis Z2.6 and Its Cellulase Production Optimization. Microorganisms 2024; 12:979. [PMID: 38792808 PMCID: PMC11124521 DOI: 10.3390/microorganisms12050979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/06/2024] [Accepted: 05/11/2024] [Indexed: 05/26/2024] Open
Abstract
Enzyme-production microorganisms typically occupy a dominant position in composting, where cellulolytic microorganisms actively engage in the breakdown of lignocellulose. Exploring strains with high yields of cellulose-degrading enzymes holds substantial significance for the industrial production of related enzymes and the advancement of clean bioenergy. This study was inclined to screen cellulolytic bacteria, conduct genome analysis, mine cellulase-related genes, and optimize cellulase production. The potential carboxymethylcellulose-hydrolyzing bacterial strain Z2.6 was isolated from the maturation phase of pig manure-based compost with algae residuals as the feedstock and identified as Bacillus velezensis. In the draft genome of strain Z2.6, 31 related cellulolytic genes were annotated by the CAZy database, and further validation by cloning documented the existence of an endo-1,4-β-D-glucanase (EC 3.2.1.4) belonging to the GH5 family and a β-glucosidase (EC 3.2.1.21) belonging to the GH1 family, which are predominant types of cellulases. Through the exploration of ten factors in fermentation medium with Plackett-Burman and Box-Behnken design methodologies, maximum cellulase activity was predicted to reach 2.98 U/mL theoretically. The optimal conditions achieving this response were determined as 1.09% CMC-Na, 2.30% salinity, and 1.23% tryptone. Validation under these specified conditions yielded a cellulose activity of 3.02 U/mL, demonstrating a 3.43-fold degree of optimization. In conclusion, this comprehensive study underscored the significant capabilities of strain Z2.6 in lignocellulolytic saccharification and its potentialities for future in-depth exploration in biomass conversion.
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Affiliation(s)
- Zhi Cai
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
- Marine College, Shandong University, Weihai 264209, China
| | - Yi Wang
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
| | - Yang You
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
| | - Nan Yang
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
| | - Shanshan Lu
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
| | - Jianheng Xue
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
| | - Xiang Xing
- SDU-ANU Joint Science College, Shandong University, Weihai 264209, China; (Z.C.); (Y.W.); (Y.Y.); (N.Y.); (S.L.); (J.X.); (X.X.)
- Marine College, Shandong University, Weihai 264209, China
| | - Sha Sha
- Marine College, Shandong University, Weihai 264209, China
| | - Lihua Zhao
- Marine College, Shandong University, Weihai 264209, China
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Boro M, Verma AK. Optimization of Cellulase Production by Cohnella xylanilytica RU-14 Using Statistical Methods. Appl Biochem Biotechnol 2024; 196:2757-2770. [PMID: 36995658 DOI: 10.1007/s12010-023-04447-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2023] [Indexed: 03/31/2023]
Abstract
In this study, the cellulase activity by bacterial strain Cohnella xylanilytica RU-14 was enhanced by optimizing the medium components using statistical methods of Plackett-Burman design (PBD) and response surface methodology-central composite design (RSM-CCD). The cellulase assay was performed using NS enzyme assay method for reducing sugars. By PBD, the most significant factors (CMC, pH, and yeast extract) in an enzyme production medium that influence cellulase production by RU-14 were identified. These identified significant variables were further optimized using RSM by CCD. It was found that under optimized conditions of the medium components, the cellulase activity increased three times up to 14.5 U/mL as compared to un-optimized conditions (5.2 U/mL) of the enzyme production medium. The optimized levels of the significant factors determined by the CCD were found to be CMC, 2.3% w/v, and yeast extract, 0.75% w/v, at pH 7.5. The most adequate temperature for cellulase production by the bacterial strain was found to be 37 °C using the one-factor-at-a-time method. Thus, statistical methods to optimize medium conditions to enhance cellulase production by Cohnella xylanilytica RU-14 were found successful.
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Affiliation(s)
- Manswama Boro
- Department of Microbiology, Sikkim University, Gangtok, 737102, Sikkim, India
| | - Anil Kumar Verma
- Department of Microbiology, Sikkim University, Gangtok, 737102, Sikkim, India.
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Ashoor S, Mathew GM, Sukumaran RK. Rice straw hydrolysis using in-situ produced enzymes: Feedstock influences fungal enzyme composition and hydrolytic efficiency. Prep Biochem Biotechnol 2024:1-7. [PMID: 38327105 DOI: 10.1080/10826068.2024.2312458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Trichoderma reesei RUT-C30 was cultivated on differentially pretreated rice straw and pure cellulose as a carbon source/inducer for cellulase production, and the enzymes were evaluated for hydrolysis of sequential acid and alkali pretreated rice straw. Growth on pretreated rice straw enhanced protein secretion and cellulase activities compared to pure cellulose as a carbon source. The yield of cellulolytic enzymes was higher for alkali pretreated rice straw (ALP-RS), while H2O2-treated (HP-RS) could not induce cellulases to a larger level compared to pure cellulose. Protein concentration was 3.5-fold higher on ALP-RS as compared to pure cellulose, with a maximum filter-paper cellulase (FPase) activity of 1.76 IU/ml and carboxy-methyl cellulase (CMCase) activity of 40.16 IU/ml (2.18 fold higher). Beta-glucosidase (BGL) activity was more or less the same with the different substrates and supplementation of heterologous BGL could result in a quantum jump in hydrolytic efficiencies, which in the case of ALP-RS induced enzymes was 34% (increased from 69.26% to 92.51%). The use of lignocellulosic biomass (LCB) itself as a substrate for the production of cellulase is advantageous not only in terms of raw material costs but also for obtaining a more suitable enzyme profile for biomass hydrolysis.
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Affiliation(s)
- Selim Ashoor
- Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Cairo, Egypt
| | - Gincy Marina Mathew
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, India
| | - Rajeev K Sukumaran
- Biofuels and Biorefineries Section, Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
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Liu G, Zhang K, Gong H, Yang K, Wang X, Zhou G, Cui W, Chen Y, Yang Y. Whole genome sequencing and the lignocellulose degradation potential of Bacillus subtilis RLI2019 isolated from the intestine of termites. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:130. [PMID: 37598218 PMCID: PMC10439612 DOI: 10.1186/s13068-023-02375-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 07/25/2023] [Indexed: 08/21/2023]
Abstract
BACKGROUND Lignocellulosic biomass is the most abundant and renewable terrestrial raw material for conversion into bioproducts and biofuels. However, the low utilization efficiency of lignocellulose causes environmental pollution and resource waste, which limits the large-scale application of bioconversion. The degradation of lignocellulose by microorganisms is an efficient and cost-effective way to overcome the challenge of utilizing plant biomass resources. This work aimed to screen valuable cellulolytic bacteria, explore its molecular mechanism from genomic insights, and investigate the ability of the strain to biodegrade wheat straw. RESULTS Bacillus subtilis (B. subtilis) RLI2019 was isolated from the intestine of Reticulitermes labralis. The strain showed comprehensive enzyme activities related to lignocellulose degradation, which were estimated as 4.06, 1.97, 4.12, 0.74, and 17.61 U/mL for endoglucanase, β-glucosidase, PASC enzyme, filter paper enzyme, and xylanase, respectively. Whole genome sequencing was performed to better understand the genetic mechanism of cellulose degradation. The genome size of B. subtilis RLI2019 was 4,195,306 bp with an average GC content of 43.54%, and the sequence characteristics illustrated an extremely high probability (99.41%) as a probiotic. The genome contained 4,381 protein coding genes with an average GC content of 44.20%, of which 145 genes were classified into six carbohydrate-active enzyme (CAZyme) families and 57 subfamilies. Eight cellulose metabolism enzyme-related genes and nine hemicellulose metabolism enzyme-related genes were annotated by the CAZyme database. The starch and sucrose metabolic pathway (ko00500) was the most enriched with 46 genes in carbohydrate metabolism. B. subtilis RLI2019 was co-cultured with wheat straw for 7 days of fermentation, the contents of neutral detergent fiber, acid detergent fiber, hemicellulose, and lignin were significantly reduced by 5.8%, 10.3%, 1.0%, and 4.7%, respectively. Moreover, the wheat straw substrate exhibited 664.9 μg/mL of reducing sugars, 1.22 U/mL and 6.68 U/mL of endoglucanase and xylanase activities, respectively. Furthermore, the fiber structures were effectively disrupted, and the cellulose crystallinity was significantly reduced from 40.2% to 36.9%. CONCLUSIONS The complex diversity of CAZyme composition mainly contributed to the strong cellulolytic attribute of B. subtilis RLI2019. These findings suggest that B. subtilis RLI2019 has favorable potential for biodegradation applications, thus it can be regarded as a promising candidate bacterium for lignocellulosic biomass degradation.
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Affiliation(s)
- Gongwei Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Ke Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Hanxuan Gong
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Kaiyao Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xiaoyu Wang
- Qinling Giant Panda Breeding Research Center, Shaanxi Academy of Forestry Sciences, Zhouzhi, 710402, Shaanxi, China
| | - Guangchen Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Wenyuan Cui
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Yulin Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
| | - Yuxin Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Phithakrotchanakoon C, Mayteeworakoon S, Siriarchawatana P, Kitikhun S, Harnpicharnchai P, Wansom S, Eurwilaichitr L, Ingsriswang S. Beneficial bacterial-Auricularia cornea interactions fostering growth enhancement identified from microbiota present in spent mushroom substrate. Front Microbiol 2022; 13:1006446. [PMID: 36299733 PMCID: PMC9589457 DOI: 10.3389/fmicb.2022.1006446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Complex dynamic bacterial-fungal interactions play key roles during mushroom growth, ranging from mutualism to antagonism. These interactions convey a large influence on mushroom’s mycelial and fruiting body formation during mushroom cultivation. In this study, high-throughput amplicon sequencing was conducted to investigate the structure of bacterial communities in spent mushroom substrates obtained from cultivation of two different groups of Auricularia cornea with (A) high yield and (B) low yield of fruiting body production. It was found that species richness and diversity of microbiota in group (A) samples were significantly higher than in group (B) samples. Among the identified 765 bacterial OTUs, 5 bacterial species found to exhibit high differential abundance between group (A) and group (B) were Pseudonocardia mangrovi, Luteimonas composti, Paracoccus pantotrophus, Sphingobium jiangsuense, and Microvirga massiliensis. The co-cultivation with selected bacterial strains showed that A. cornea TBRC 12900 co-cultivated with P. mangrovi TBRC-BCC 42794 promoted a high level of mycelial growth. Proteomics analysis was performed to elucidate the biological activities involved in the mutualistic association between A. cornea TBRC 12900 and P. mangrovi TBRC-BCC 42794. After co-cultivation of A. cornea TBRC 12900 and P. mangrovi TBRC-BCC 42794, 1,616 proteins were detected including 578 proteins of A. cornea origin and 1,038 proteins of P. mangrovi origin. Functional analysis and PPI network construction revealed that the high level of mycelial growth in the co-culture condition most likely resulted from concerted actions of (a) carbohydrate-active enzymes including hydrolases, glycosyltransferases, and carbohydrate esterases important for carbohydrate metabolism and cell wall generation/remodeling, (b) peptidases including cysteine-, metallo-, and serine-peptidases, (c) transporters including the ABC-type transporter superfamily, the FAT transporter family, and the VGP family, and (d) proteins with proposed roles in formation of metabolites that can act as growth-promoting molecules or those normally contain antimicrobial activity (e.g., indoles, terpenes, β-lactones, lanthipeptides, iturins, and ectoines). The findings will provide novel insights into bacterial-fungal interactions during mycelial growth and fruiting body formation. Our results can be utilized for the selection of growth-promoting bacteria to improve the cultivation process of A. cornea with a high production yield, thus conveying potentially high socio-economic impact to mushroom agriculture.
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Affiliation(s)
- Chitwadee Phithakrotchanakoon
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Sermsiri Mayteeworakoon
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Paopit Siriarchawatana
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Supattra Kitikhun
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Piyanun Harnpicharnchai
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Supaporn Wansom
- National Energy Technology Center, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Lily Eurwilaichitr
- National Energy Technology Center, National Science and Technology Development Agency, Pathum Thani, Thailand
| | - Supawadee Ingsriswang
- Microbial Systems and Computational Biology Research Team, Thailand Bioresource Research Center, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathum Thani, Thailand
- *Correspondence: Supawadee Ingsriswang,
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Screening of Cellulolytic Bacteria from Various Ecosystems and Their Cellulases Production under Multi-Stress Conditions. Catalysts 2022. [DOI: 10.3390/catal12070769] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Cellulose represents the most abundant component of plant biomass on earth; it is degraded by cellulases, specific enzymes produced by microorganisms. However, cellulases of bacterial origin attract more interest due to their natural diversity and ability to inhabit a variety of niches, allowing the selection of cellulolytic strains resistant to environmental stresses. The screening of the cellulolytic activity of 398 bacteria isolated from various ecosystems in Algeria (cave, ruins, chott, thermal station, and rhizosphere of arid and semi-arid regions) was performed by the appearance of a hydrolysis zone on carboxymethylcellulose (CMC) medium. The cellulase activity on CMC (1%) broth allowed to select 26 strains among which 12 had the best activity (0.3 U/mL to 2.2 U/mL). Optimization of physicochemical parameters (salinity: 0–1 M NaCl; pH: 3, 4, 7, 9, and 11; temperature: 30, 45, and 50 °C; PEG8000: 0 and 30%) involved in growth and cellulose production showed that the majority of strains were mesophilic, neutrophilic, or alkali- tolerant and tolerant to 30% of PEG8000. The cellulase activity and stability under different stress allowed to retain five strains, which the most efficient. Based on the 16S-rRNA sequencing results, they belonged to the genus Bacillus. The physicochemical properties of cellulases (crude extract) showed a CMCase active over a wide range of pH (4 to 11), optimal at 50 °C and 60 °C. The inhibiting salinity effect on the activity was not detected and was negligible on the enzymatic stability. The residual CMCase activity remained between 40 and 70% in a temperature range between 40 and 70 °C, was stable over a wide range of saline concentrations (0–2000 mM), and was weakly affected at 30% of PEG8000. The crude enzyme extract was able to hydrolyze both soluble and insoluble cellulosic substrates. The evaluation of the hydrolysis capacity of lignocellulosic waste revealed the ability of tested strains to degrade wheat bran, barley bran, and corncob. In addition, the enzyme showed significant multi-stress resistance on solid and liquid media. By these characteristics, these cellulolytic bacteria could be attractive to be used in various industrial and biotechnology applications.
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Mohammadi S, Tarrahimofrad H, Arjmand S, Zamani J, Haghbeen K, Aminzadeh S. Expression, characterization, and activity optimization of a novel cellulase from the thermophilic bacteria Cohnella sp. A01. Sci Rep 2022; 12:10301. [PMID: 35717508 PMCID: PMC9206686 DOI: 10.1038/s41598-022-14651-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 06/09/2022] [Indexed: 11/09/2022] Open
Abstract
Cellulases are hydrolytic enzymes with wide scientific and industrial applications. We described a novel cellulase, CelC307, from the thermophilic indigenous Cohnella sp. A01. The 3-D structure of the CelC307 was predicted by comparative modeling. Docking of CelC307 with specific inhibitors and molecular dynamic (MD) simulation revealed that these ligands bound in a non-competitive manner. The CelC307 protein was purified and characterized after recombinant expression in Escherichia coli (E. coli) BL21. Using CMC 1% as the substrate, the thermodynamic values were determined as Km 0.46 mM, kcat 104.30 × 10-3 (S-1), and kcat/Km 226.73 (M-1 S-1). The CelC307 was optimally active at 40 °C and pH 7.0. The culture condition was optimized for improved CelC307 expression using Plackett-Burman and Box-Behnken design as follows: temperature 20 °C, pH 7.5, and inoculation concentration with an OD600 = 1. The endoglucanase activity was positively modulated in the presence of Na+, Li+, Ca2+, 2-mercaptoethanol (2-ME), and glycerol. The thermodynamic parameters calculated for CelC307 confirmed its inherent thermostability. The characterized CelC307 may be a suitable candidate for various biotechnological applications.
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Affiliation(s)
- Shima Mohammadi
- Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Hossein Tarrahimofrad
- Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Sareh Arjmand
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
| | - Javad Zamani
- Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Kamahldin Haghbeen
- Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Saeed Aminzadeh
- Bioprocess Engineering Group, Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
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Das T, Ali F, Rahman MS. Cellulase activity of a novel bacterial strain Arthrobacter woluwensis TDS9: its application on bioconversion of paper mill sludge. J Genet Eng Biotechnol 2022; 20:87. [PMID: 35708781 PMCID: PMC9203635 DOI: 10.1186/s43141-022-00373-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 05/24/2022] [Indexed: 01/08/2023]
Abstract
Background Lignocellulosic biomasses produced from agriculture and forest-based industries are the cheapest or negative-cost biomass with a great potential for biotransformation to value-added bioproducts. Paper mill sludge, an important lignocellulosic biomass creates an environmental threat, which requires financial input for disposal. Thus, this study was aimed to isolate a novel bacterial strain capable of degrading cellulosic biomass including paper mill sludge to produce reducing sugar and other value-added bioproducts. Results A novel bacterial strain Arthrobacter woluwensis TDS9 isolated from the soil was screened for its cellulolytic activity using carboxymethyl cellulose (CMC) as the sole carbon source. The incubation period, temperature, pH, carbon, and nitrogen sources are the most important factors ruling the CMCase and sugar productions of the strain A. woluwensis TDS9, and an alkaline pH (pH 8.0) led to enhanced sugar production up to 1100.09 μg/mL after 72 h of incubation at 25°C in a medium containing 1.5% CMC and 1.25% beef extract. The optimal conditions for maximum CMCase activity were defined, and the potassium ion boosted the CMCase activity up to 1.06 U/mL when the enzymatic reaction was performed for 30 min at 50°C and pH 8 using CMC as a substrate. Moreover, the strain A. woluwensis TDS9 produced 433.33 μg/mL reducing sugar from 1% pretreated paper mill sludge. Significant alterations in the structural arrangement of cellulosic fiber of paper mill sludge observed under microscope after each step of chemical treatment process helped for loosening the cellulose fibers and increased the saccharification for enzymatic hydrolysis. Endoglucanase IV (33 KDa) and beta-glucosidase II (53 KDa) were identified in crude enzyme based on the zymogram analysis and substrate specificity. Conclusions The research has for the first time proved that this A. woluwensis TDS9 strain can efficiently convert cellulose. Therefore, the strain TDS9 could be a potential candidate for cellulase production in an industrial biotransformation process of paper mill sludge to produce reducing sugar. This sugar stream can be further used as a substrate to produce biofuels and other organic acids using another microorganism, which represents a greener alternative to add value to the paper production helping paper mill industries.
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Affiliation(s)
- Tuhin Das
- Department of Microbiology, University of Chittagong, Chattogram, 4331, Bangladesh
| | - Ferdausi Ali
- Department of Microbiology, University of Chittagong, Chattogram, 4331, Bangladesh
| | - Md Shafiqur Rahman
- Department of Microbiology, University of Chittagong, Chattogram, 4331, Bangladesh. .,Department of Biology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, Canada.
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Santos GB, de Sousa Francisco Filho Á, Rêgo da Silva Rodrigues J, Rodrigues de Souza R. Cellulase production by Aspergillus niger using urban lignocellulosic waste as substrate: Evaluation of different cultivation strategies. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 305:114431. [PMID: 34995940 DOI: 10.1016/j.jenvman.2022.114431] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 12/08/2021] [Accepted: 01/02/2022] [Indexed: 06/14/2023]
Abstract
Cellulases are used in various industries, acting efficiently and sustainably in the degradation of cellulose contained in different raw materials and recovering high value products. It is the third largest group of enzymes consumed industrially, as they are required in processes linked to the food, biofuel, textile, cleaning products, among others. However, the main disadvantage in the use of commercial cellulases is the high cost. In this context, the objective of this work was to determine conditions for obtaining more efficient and economical cellulases. For this, the efficiency in obtaining the extracellular cellulases endoglucanase (CMCase) and exoglucanase (FPase) by a fungus Aspergillus niger was investigated using an urban lignocellulosic waste as substrate characterized by tree leaves collected from squares and avenues in urban areas. As urban lignocellulosic waste is an innovative raw material, its chemical composition was determined. This substrate contains 20.36% cellulose and induced the production of cellulases in all fermentation methods, proving to be a promising and sustainable source. The influence of the nutrient medium on CMCase and FPase activities was evaluated for three different sequential fermentation (SF) configurations. Medium 2 provided an increase of up to 100 U/L of CMCase and FPase in relation to medium 1. The interactive effect of pH and moisture content on CMCase e FPase production under SF was studied in a central composite design (CCD). Also, different fermentation methods (solid state, submerged and sequential) were evaluated. The use of SF increased the enzymatic activities of both cellulases by 140% compared to other conventional methods and also stood out in the production of proteins (270.05 μg/mL) and reducing sugars (1.19 mg/mL). The desirability function determined the optimal activities of CMCase and FPase as 413.49 U/L and 230.68 U/L, respectively, obtained from the optimal variables of pH 5.5 and 75% moisture content under SF. The effect of pH and moisture content on the activity of each cellulase was analyzed using the Pareto chart and response surface methodology (RSM). These results revealed favorable strategies for cellulase production, such as the use of urban lignocellulosic waste, SF and ideal operational conditions.
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Affiliation(s)
- Gislaine Brito Santos
- Department of Chemical Engineering, Federal University of Sergipe, 49100-000, Sergipe, Brazil.
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Malik WA, Javed S. Biochemical Characterization of Cellulase From Bacillus subtilis Strain and its Effect on Digestibility and Structural Modifications of Lignocellulose Rich Biomass. Front Bioeng Biotechnol 2022; 9:800265. [PMID: 34988069 PMCID: PMC8721162 DOI: 10.3389/fbioe.2021.800265] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
Microbial cellulases have become the mainstream biocatalysts due to their complex nature and widespread industrial applications. The present study reports the partial purification and characterization of cellulase from Bacillus subtilis CD001 and its application in biomass saccharification. Out of four different substrates, carboxymethyl cellulose, when amended as fermentation substrate, induced the highest cellulase production from B. subtilis CD001. The optimum activity of CMCase, FPase, and amylase was 2.4 U/ml, 1.5 U/ml, and 1.45 U/ml, respectively. The enzyme was partially purified by (NH4)2SO4 precipitation and sequenced through LC-MS/MS. The cellulase was found to be approximately 55 kDa by SDS-PAGE and capable of hydrolyzing cellulose, as confirmed by zymogram analysis. The enzyme was assigned an accession number AOR98335.1 and displayed 46% sequence homology with 14 peptide-spectrum matches having 12 unique peptide sequences. Characterization of the enzyme revealed it to be an acidothermophilic cellulase, having an optimum activity at pH 5 and a temperature of 60°C. Kinetic analysis of partially purified enzyme showed the Km and Vmax values of 0.996 mM and 1.647 U/ml, respectively. The enzyme activity was accelerated by ZnSO4, MnSO4, and MgSO4, whereas inhibited significantly by EDTA and moderately by β-mercaptoethanol and urea. Further, characterization of the enzyme saccharified sugarcane bagasse, wheat straw, and filter paper by SEM, ATR-FTIR, and XRD revealed efficient hydrolysis and structural modifications of cellulosic materials, indicating the potential industrial application of the B. subtilis CD001 cellulase. The findings demonstrated the potential suitability of cellulase from B. subtilis CD001 for use in current mainstream biomass conversion into fuels and other industrial processes.
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Affiliation(s)
- Waseem Ayoub Malik
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
| | - Saleem Javed
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, India
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Cheng Y, Huang M, Shen X, Jiang C. Enhanced cornstalk decomposition by a psychrotrophic bacterial consortium comprising cellulose, hemicellulose, and lignin degraders with biochar as a carrier for carbonneutrality. BIORESOURCE TECHNOLOGY 2022; 344:126259. [PMID: 34775050 DOI: 10.1016/j.biortech.2021.126259] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 06/13/2023]
Abstract
To explore an effective approach for accelerating cornstalk decomposition and return under low temperature, nine psychrotrophic cellulose-, hemicellulose-, and lignin-degrading bacterial strains were used with biochar as the carrier to prepare a novel psychrotrophic stalk-degrading bacterial consortium (PSBC). With PSBC, the maximum cornstalk degradation rate reached 59.3% after 50 d at 10-15 °C, which accelerated cornstalk decomposition, resulting in increases in organic matter, phosphorus, and potassium in the soil. Microbial community analysis demonstrated that PSBC enhanced microbial community diversity and altered specific selection. Genera Arthrobacter, Pseudomonas, and Pantoea in PSBC became dominant in the soil microbiota, which benefited cornstalk degradation. Therefore, this work provides a promising strategy to facilitate the degradation of cornstalks in cold regions, which has potential application value for carbon neutrality.
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Affiliation(s)
- Yi Cheng
- College of Science, China Agricultural University, Beijing 100083, PR China
| | - Mingyan Huang
- Jiangsu hengrui medicine Co., Ltd., Jiangsu 222002, PR China
| | - Xiaohui Shen
- College of Life Sciences and Resources and Environment, Yichun University, Yichun 336000, Jiangxi, PR China
| | - Cheng Jiang
- College of Life Sciences and Resources and Environment, Yichun University, Yichun 336000, Jiangxi, PR China.
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Sinha D, Banerjee S, Mandal S, Basu A, Banerjee A, Balachandran S, Chandra Mandal N, Chaudhury S. Enhanced biogas production from Lantana camara via bioaugmentation of cellulolytic bacteria. BIORESOURCE TECHNOLOGY 2021; 340:125652. [PMID: 34332446 DOI: 10.1016/j.biortech.2021.125652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/19/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
A study was designed to isolate cellulolytic bacteria from termite-gut and soil, optimizing their cellulase production to enhance biogas generation, using Lantana camara as a substrate. Out of 57 bacteria screened, two isolates DSB1 and DSB12, showed significant cellulolytic activity. 16S rRNA based methods identified these isolates as Microbacterium sp. and Arthrobacter sp. respectively. Maximum cellulase activity of 1.26 ± 0.044 U/ml and 1.31 ± 0.052 U/ml for DSB1 and DSB12 was observed at pH 7 and 7.2 under 35⁰C and 37⁰C, respectively. The L. camara biomass substrate with cow dung as an inoculum, bioaugmented with DSB1 and DSB12 separately, was tested for biogas production, producing 950 l/kg and 980 l/kg VS biogas with 57% and 60% methane, respectively. DSB1 and DSB12 revealed as potent cellulase producers that can be harnessed in the anaerobic digester for biomass conversion practices for enhanced biogas production.
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Affiliation(s)
- Debasree Sinha
- Department of Environmental Studies, Siksha -Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India
| | - Sandipan Banerjee
- Mycology and Plant Pathology Laboratory, Department of Botany, Siksha-Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India
| | - Subhrangshu Mandal
- Department of Botany, Siksha-Bhavana, Visva-Bharati, Santiniketan, Birbhum, West Bengal, 731235, India
| | - Aman Basu
- Department of Environmental Studies, Siksha -Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India; Department of Biology, York University, Toronto, Ontario, Canada
| | - Aishiki Banerjee
- Department of Environmental Studies, Siksha -Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India
| | - Srinivasan Balachandran
- Department of Environmental Studies, Siksha -Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India
| | - Narayan Chandra Mandal
- Mycology and Plant Pathology Laboratory, Department of Botany, Siksha-Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India
| | - Shibani Chaudhury
- Department of Environmental Studies, Siksha -Bhavana, Visva-Bharati, Santiniketan, West Bengal, 731235, India.
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Vadala BS, Deshpande S, Apte-Deshpande A. Soluble expression of recombinant active cellulase in E.coli using B.subtilis (natto strain) cellulase gene. J Genet Eng Biotechnol 2021; 19:7. [PMID: 33428026 PMCID: PMC7801579 DOI: 10.1186/s43141-020-00103-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 12/07/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND Cellulases are well known for their various industrial applications. They are naturally produced by different species of bacteria and fungi. Fermentation process of cellulase producers has limitation due to the high substrate cost required for cellulase induction and challenges to maintain the suitable condition for the respective cellulase production. Recombinant cellulase production could be the potential solution to these problems. In the current study, we investigated recombinant cellulase expression in Escherichia coli using cellulase gene from Bacillus subtilis. RESULTS Extracellular cellulase production from B. subtilis strain was first confirmed on CMC agar and then the cellulase gene (1500 bp) was amplified from this strain and was further cloned in pET21a expression vector. In initial experimental studies, recombinant cellulase expression was achieved in inclusion bodies through shake flask level fermentation of transformed E. coli expression host BL21DE3. Attempts were made to express this 55 KDa His tagged recombinant cellulase into soluble form by modifications in fermentation conditions. Partially purified recombinant cellulase was obtained using Ni-NTA affinity chromatography. The activity of the purified enzyme was confirmed by 3,5-dinitrosalicylic acid (DNS) qualitative assay. CONCLUSION Soluble expression of active recombinant cellulase can be achieved by subtle alteration in the upstream process.
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Affiliation(s)
- Bhuvan Shankar Vadala
- Central Dogma Pvt. Ltd, A4, Gulmohar Residency, Baner Road, Baner, Pune, Maharashtra, 411045, India
| | - Sumedh Deshpande
- Central Dogma Pvt. Ltd, A4, Gulmohar Residency, Baner Road, Baner, Pune, Maharashtra, 411045, India
| | - Anjali Apte-Deshpande
- Central Dogma Pvt. Ltd, A4, Gulmohar Residency, Baner Road, Baner, Pune, Maharashtra, 411045, India.
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Jain D, Ravina, Bhojiya AA, Chauhan S, Rajpurohit D, Mohanty SR. Polyphasic Characterization of Plant Growth Promoting Cellulose Degrading Bacteria Isolated from Organic Manures. Curr Microbiol 2021; 78:739-748. [PMID: 33416972 DOI: 10.1007/s00284-020-02342-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 12/18/2020] [Indexed: 10/22/2022]
Abstract
In the present study, twenty seven cellulose-degrading bacteria (CDB) were isolated from various organic manures and their cellulolytic activities were determined. The bacterial isolate CDB-26 showed the highest cellulolytic index, released 0.507 ± 0.025 mg/ml glucose and produced 0.196 ± 0.014 IU/ml cellulase enzyme under in vitro conditions. Biochemically, all the 27 isolates showed difference in the 6 biochemical tests performed. Further, all the 27 CDB isolates were subjected to various plant growth-promoting activities, and all CDB strains were positive for IAA production, GA3 production and siderophore production, whereas 19 strains were positive for ACC deaminase activity, 21 strains showed NH3 production and 19 strains were positive for HCN production. Out of 27 CDB isolates, 18 isolates were able to solubilize phosphate, 21 isolates were able to solubilize potash and 10 CDB isolates were found positive for silica solubilization. The molecular diversity among different CDB isolates was studied through ARDRA and demonstrated very high genetic diversity among these bacteria. The in vitro cellulose-degradation potential of these CDB isolates using vegetable waste as substrate were also assessed, and the 3 CDB isolates viz. Serratia surfactantfaciens (CDB-26), Stenotrophomonas rhizophila (CDB-16) and Pseudomonas fragi (CDB-5) showed the highest cellulose-degrading potential under in vitro conditions. Hence, the cellulolytic microbes isolated in the present study could be used for effective bioconversion of plant biomasses into enriched compost.
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Affiliation(s)
- Devendra Jain
- Department of Molecular Biology and Biotechnology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, India.
| | - Ravina
- Department of Molecular Biology and Biotechnology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, India
| | - Ali Asger Bhojiya
- Department of Molecular Biology and Biotechnology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, India.,Department of Agriculture and Veterinary Sciences, Mewar University, Chittaurgarh, Rajasthan, India
| | - Surya Chauhan
- Department of Molecular Biology and Biotechnology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, India
| | - Deepak Rajpurohit
- Department of Molecular Biology and Biotechnology, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur, 313001, India
| | - Santosh R Mohanty
- Indian Institute of Soil Science, Indian Council of Agricultural Research, Bhopal, Madhya Pradesh, 462038, India
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Yang YC, Huang WS, Hu SM, Huang CW, Chiu CH, Chen HY. Synergistic and Regulatable Bioremediation Capsules Fabrication Based on Vapor-Phased Encapsulation of Bacillus Bacteria and its Regulator by Poly- p-Xylylene. Polymers (Basel) 2020; 13:polym13010041. [PMID: 33374286 PMCID: PMC7795076 DOI: 10.3390/polym13010041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/17/2020] [Accepted: 12/22/2020] [Indexed: 02/03/2023] Open
Abstract
A regulatable bioremediation capsule material was synthesized with isolated single-strain bacteria (Bacillus species, B. CMC1) and a regulator molecule (carboxymethyl cellulose, CMC) by a vapor-phased encapsulation method with simple steps of water sublimation and poly-p-xylylene deposition in chemical vapor deposition (CVD) process. Mechanically, the capsule construct exhibited a controllable shape and dimensions, and was composed of highly biocompatible poly-p-xylylene as the matrix with homogeneously distributed bacteria and CMC molecules. Versatility of the encapsulation of the molecules at the desired concentrations was achieved in the vapor-phased sublimation and deposition fabrication process. The discovery of the fabricated capsule revealed that viable living B. CMC1 inhabited the capsule, and the capsule enhanced bacterial growth due to the materials and process used. Biologically, the encapsulated B. CMC1 demonstrated viable and functional enzyme activity for cellulase activation, and such activity was regulatable and proportional to the concentration of the decorated CMC molecules in the same capsule construct. Impressively, 13% of cellulase activity increase was realized by encapsulation of B. CMC1 by poly-p-xylylene, and a further 34% of cellulase activity increase was achieved by encapsulation of additional 2.5% CMC. Accordingly, this synergistic effectiveness of the capsule constructs was established by combining enzymatic B. CMC1 bacteria and its regulatory CMC by poly-p-xylylene encapsulation process. This reported encapsulation process exhibited other advantages, including the use of simple steps and a dry and clean process free of harmful chemicals; most importantly, the process is scalable for mass production. The present study represents a novel method to fabricate bacteria-encapsulated capsule for cellulose degradation in bioremediation that can be used in various applications, such as wastewater treatment and transforming of cellulose into glucose for biofuel production. Moreover, the concept of this vapor-phased encapsulation technology can be correspondingly used to encapsulate multiple bacteria and regulators to enhance the specific enzyme functions for degradation of various organic matters.
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Affiliation(s)
- Yen-Ching Yang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Y.-C.Y.); (S.-M.H.); (C.-W.H.)
| | - Wei-Shen Huang
- Institute of Oceanography, National Taiwan University, Taipei 10617, Taiwan;
| | - Shu-Man Hu
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Y.-C.Y.); (S.-M.H.); (C.-W.H.)
| | - Chao-Wei Huang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Y.-C.Y.); (S.-M.H.); (C.-W.H.)
| | - Chih-Hao Chiu
- Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Taoyuan 33378, Taiwan
- Bone and Joint Research Center, Chang Gung Memorial Hospital, Linkou 33305, Taiwan
- Correspondence: (C.-H.C.); (H.-Y.C.); Tel.: +886-2-33669476 (H.-Y.C.)
| | - Hsien-Yeh Chen
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Y.-C.Y.); (S.-M.H.); (C.-W.H.)
- Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan
- Advanced Research Center for Green Materials Science and Technology, National Taiwan University, Taipei 10617, Taiwan
- Correspondence: (C.-H.C.); (H.-Y.C.); Tel.: +886-2-33669476 (H.-Y.C.)
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Isolation and Characterisation of Endophytic Bacteria from Holostemma ada-kodien Schult. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2020. [DOI: 10.22207/jpam.14.3.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plants with medical properties are often enriched with endophytes that have the potential to produce important bioactive compounds. Endophytes after entering the plant tissue may either colonize a particular tissue or may spread throughout the host plant without causing damage. The possession of pharmaceutical and biological properties has made the Holostemma ada-kodien Schult as one of the widely used plants of medicinal importance in India. Following the direct cut method three endophytic bacterial strains (UC H1, UC H4 and UC H7) were isolated, identified and characterized from the healthy looking rhizome of H. ada-kodien. Among these isolates, UC H1 and UC H4 were found to have many properties like antibacterial compounds, hydrolytic enzymes and plant growth promoting traits. The isolate UC H4 have ability for Indole-3-Acetic Acid (IAA) production of 513.54 U/ml and very good protease and pectinase activities of 20.65 U/ml and 16.09 U/ml respectively. So far no reports are available on the endophytic microflora of H. ada-kodien.
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Ahmad T, Sharma A, Gupta G, Mansoor S, Jan S, Kaur B, Paray BA, Ahmad A. Response surface optimization of cellulase production from Aneurinibacillus aneurinilyticus BKT-9: An isolate of urban Himalayan freshwater. Saudi J Biol Sci 2020; 27:2333-2343. [PMID: 32884415 PMCID: PMC7451742 DOI: 10.1016/j.sjbs.2020.04.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 04/12/2020] [Accepted: 04/19/2020] [Indexed: 11/16/2022] Open
Abstract
Due to their vast industrial potential, cellulases have been regarded as the potential biocatalysts by both the academicians and the industrial research groups. In the present study, culturable bacterial strains of Himalayan Urban freshwater lake were investigated for cellulose degrading activities. Initially, a total of 140 bacterial strains were isolated and only 45 isolates were found to possess cellulose degrading property. On the basis of preliminary screening involving cellulase activity assay on CMC agar (with clear zone of hydrolysis) and biosafety assessment testing, only single isolate named as BKT-9 was selected for the cellulase production studies. Strain BKT-9 was characterized at the molecular level using rRNA gene sequencing and its sequence homology analysis revealed its identity as Aneurinibacillus aneurinilyticus. Further, various physico-chemical parameters and culture conditions were optimized using one factor approach to enhance cellulase production levels in the strain BKT-9. Subsequently, RSM based statistical optimization led to formulation of cellulase production medium, wherein the bacterial strain exhibited ~60 folds increase in enzyme activity as compared to un-optimized culture medium. Further studies are being suggested to scale up cellulase production in A. aneurinilyticus strain BKT-9 so that it can be utilized for biomass saccharification at an industrial level.
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Affiliation(s)
- Tawseef Ahmad
- Department of Biotechnology, Punjabi University Patiala, Punjab 147002, India
| | - Anshula Sharma
- Department of Biotechnology, Punjabi University Patiala, Punjab 147002, India
| | - Gaganjot Gupta
- Department of Biotechnology, Punjabi University Patiala, Punjab 147002, India
| | | | - Sumira Jan
- Division of Biochemistry, SKUAST Kashmir, 190025, India
| | - Baljinder Kaur
- Department of Biotechnology, Punjabi University Patiala, Punjab 147002, India
| | - Bilal Ahmad Paray
- Department of Zoology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ajaz Ahmad
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
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Nanjundaswamy A, Okeke BC. Comprehensive Optimization of Culture Conditions for Production of Biomass-Hydrolyzing Enzymes of Trichoderma SG2 in Submerged and Solid-State Fermentation. Appl Biochem Biotechnol 2020; 191:444-462. [PMID: 32248370 DOI: 10.1007/s12010-020-03258-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 02/13/2020] [Indexed: 11/29/2022]
Abstract
Lignocellulose biomass contain large macromolecules especially cellulose and hemicelluloses that can be converted to fuel and chemicals using microbial biocatalysts. This study presents comprehensive optimization of production of biomass-hydrolyzing enzymes (BHE) by a high β-glucosidase-producing Trichoderma SG2 for bioconversion of lignocellulose biomass. Overall, a mixture of paper powder and switchgrass was most suited for production of BHE in submerged fermentation (SmF). BHE production was significantly different for various organic and inorganic nitrogen sources. The combination of peptone, yeast extract, and ammonium sulfate resulted in the highest activities (Units/mL) of BHE: 9.85 ± 0.55 cellulase, 38.91 ± 0.31 xylanase, 21.19 ± 1.35 β-glucosidase, and 7.63 ± 0.31 β-xylosidase. Surfactants comparably enhanced BHE production. The highest cellulase activity (4.86 ± 0.55) was at 25 °C, whereas 35 °C supported the highest activities of xylanase, β-glucosidase, and β-xylosidase. A broad initial culture pH (4-7) supported BHE production. The Topt for cellulase and xylanase was 50 °C. β-xylosidase and β-glucosidase were optimally active at 40 and 70 °C, respectively; pH 5 resulted in highest cellulase, β-glucosidase, and β-xylosidase activities; and pH 6 resulted in highest xylanase activity. Response surface methodology (RSM) was used to optimize major medium ingredients. BHE activities were several orders of magnitude higher in solid-state fermentation (SSF) than in SmF. Therefore, SSF can be deployed for one-step production of complete mixture of Trichoderma SG2 BHE for bioconversion of biomass to saccharide feedstock.
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Affiliation(s)
- Ananda Nanjundaswamy
- Bioprocessing and Biofuel Research Lab, Department of Biology and Environmental Science, Auburn University at Montgomery, Montgomery, AL, USA. .,Department of Agriculture, School of Agriculture and Applied Sciences, Alcorn State University, Lorman, MS, USA.
| | - Benedict C Okeke
- Bioprocessing and Biofuel Research Lab, Department of Biology and Environmental Science, Auburn University at Montgomery, Montgomery, AL, USA.
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López-Domínguez CM, Ramírez-Sucre MO, Rodríguez-Buenfil IM. Enzymatic hydrolysis of Opuntia ficus-indica cladode by Acinetobacter pittii and alcohol fermentation by Kluyveromyces marxianus: pH, temperature and microorganism effect. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2019; 24:e00384. [PMID: 31763197 PMCID: PMC6864331 DOI: 10.1016/j.btre.2019.e00384] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 09/19/2019] [Accepted: 10/05/2019] [Indexed: 10/31/2022]
Abstract
In the present work the effect of three factors: pH, temperature and type of microorganism using a factorial design 32x2 was evaluated on: growth, total cellulases hydrolytic activity (FPases), endoglucanases hydrolytic activity (CMCases), free reducing sugars (FRS), glucose, sucrose, and alcohol production using a culture medium based on mineral salts added with cladodes flour of Opuntia ficus-indica at 20% as the unique carbon source. Two wild microorganisms were used, Acinetobacter pittii a bacteria isolated from decaying cladodes, and Kluyveromyces marxianus a yeast isolated from termite stomach. The maximum hydrolytic activities were obtained with Acinetobacter pittii at 37 °C and pH 6.5 for total cellulases (0.67 ± 0.02 IU/ml) and for endoglucanases (0.23 ± 0.02 IU/ml) at 24 and 4 h. The maximum production of alcohol was 12.98 ± 0.06 g/L obtained with Kluyveromyces marxianus at 4 h with conditions of 40 °C and pH 5.5.
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Affiliation(s)
- C M López-Domínguez
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A.C. Unidad Sureste, Interior del Parque Científico y Tecnológico Yucatán, Tablaje catastral No. 31264, km 5.5 carretera Sierra Papacal-Chuburná Puerto, 97302, Mérida, Yucatán, Mexico
| | - M O Ramírez-Sucre
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A.C. Unidad Sureste, Interior del Parque Científico y Tecnológico Yucatán, Tablaje catastral No. 31264, km 5.5 carretera Sierra Papacal-Chuburná Puerto, 97302, Mérida, Yucatán, Mexico
| | - I M Rodríguez-Buenfil
- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, A.C. Unidad Sureste, Interior del Parque Científico y Tecnológico Yucatán, Tablaje catastral No. 31264, km 5.5 carretera Sierra Papacal-Chuburná Puerto, 97302, Mérida, Yucatán, Mexico
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Sahoo K, Sahoo RK, Gaur M, Subudhi E. Cellulolytic thermophilic microorganisms in white biotechnology: a review. Folia Microbiol (Praha) 2019; 65:25-43. [DOI: 10.1007/s12223-019-00710-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 04/15/2019] [Indexed: 10/26/2022]
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21
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Raza A, Bashir S, Tabassum R. Statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92 with their application in biomass saccharification. Folia Microbiol (Praha) 2018; 64:295-305. [PMID: 30361878 DOI: 10.1007/s12223-018-0654-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/04/2018] [Indexed: 11/25/2022]
Abstract
Endo-glucanase (cellulase) and xylanase have high industrial demand due to their vast application in industrial processes. This study reports statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92. Response surface methodology (RSM) involving central composite design (CCD) with full factorial experiments (23) was applied to elucidate the components that significantly affect co-production of endo-glucanase and xylanase. The optimum co-production conditions for endo-glucanase and xylanase were as follows: carboxymethyl cellulose (CMC) 20 g/L, yeast extract 15 g/L, and time 72 h. The maximum endo-glucanase and xylanase production obtained was 1.46 and 5.69 U/mL, respectively, while the minimum endo-glucanase and xylanase production obtained was 0.66 and 0.25 U/mL, respectively. This statistical model was efficient because only 20 experimental runs were necessary to assess the highest production conditions, and the model accuracy was very satisfactory as coefficient of determination (R2) was 0.95 and 0.89 for endo-glucanase and xylanase, respectively. Further, potential application of these enzymes for saccharification of lignocellulosic biomass (wheat bran, wheat straw, rice straw, and cotton stalk) was also investigated. The results revealed that the biomass was susceptible to enzymatic saccharification and the amount of reducing sugars (glucose and xylose) increased with increase in incubation time. In conclusion, Bacillus sonorensis BD92 reveals a promise as a source of potential endo-glucanase and xylanase producer that could be useful for degrading plant biomass into value-added products of economic importance using precise statistically optimized conditions.
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Affiliation(s)
- Ahmad Raza
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan
- Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
| | - Saira Bashir
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan.
- Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan.
| | - Romana Tabassum
- National Institute for Biotechnology and Genetic Engineering (NIBGE), P.O. Box 577, Jhang Road, Faisalabad, Pakistan
- Pakistan Institute of Engineering and Applied Sciences (PIEAS), Islamabad, Pakistan
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22
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Kalbarczyk KZ, Mazeau EJ, Rapp KM, Marchand N, Koffas MAG, Collins CH. Engineering Bacillus megaterium Strains To Secrete Cellulases for Synergistic Cellulose Degradation in a Microbial Community. ACS Synth Biol 2018; 7:2413-2422. [PMID: 30226981 DOI: 10.1021/acssynbio.8b00186] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Recent environmental concerns have intensified the need to develop systems to degrade waste biomass for use as an inexpensive carbon source for microbial chemical production. Current approaches to biomass utilization rely on pretreatment processes that include expensive enzymatic purification steps for the requisite cellulases. We aimed to engineer a synthetic microbial community to synergistically degrade cellulose by compartmentalizing the system with multiple specialized Bacillus megaterium strains. EGI1, an endoglucanase, and Cel9AT, a multimodular cellulase, were targeted for secretion from B. megaterium. A small library of signal peptides (SPs) with five amino acid linkers was selected to tag each cellulase for secretion from B. megaterium. Cellulase activity against amorphous cellulose was confirmed through a series of bioassays, and the most active SP constructs were identified as EGI1 with the LipA SP and Cel9AT with the YngK SP. The activity of the optimized cellulase secretion strains was characterized individually and in tandem to assess synergistic cellulolytic activity. The combination of EGI1 and Cel9AT yielded higher activity than either single cellulase. A coculture of EGI1 and Cel9AT secreting B. megaterium strains demonstrated synergistic behavior with higher activity than either monoculture. This cellulose degradation module can be further integrated with bioproduct synthesis modules to build complex systems for the production of high value molecules.
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Affiliation(s)
- Karolina Z. Kalbarczyk
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Emily J. Mazeau
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Kent M. Rapp
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Nicholas Marchand
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Mattheos A. G. Koffas
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Cynthia H. Collins
- Center for Biotechnology and Interdisciplinary Studies and Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
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Nair AS, Al-Battashi H, Al-Akzawi A, Annamalai N, Gujarathi A, Al-Bahry S, Dhillon GS, Sivakumar N. Waste office paper: A potential feedstock for cellulase production by a novel strain Bacillus velezensis ASN1. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 79:491-500. [PMID: 30343780 DOI: 10.1016/j.wasman.2018.08.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 08/05/2018] [Accepted: 08/06/2018] [Indexed: 06/08/2023]
Abstract
This paper reports the cellulase (FPase) production by newly isolated Bacillus velezensis ASN1 using waste office paper (WOP) as feedstock and optimization of production conditions through two level factorial design, steepest ascent/descent and second order response surface methodology (RSM). Various fermentation parameters, like chemical factors (potassium dihydrogen phosphate, potassium chloride, yeast extract, magnesium sulphate, sodium nitrate, Tween 80, and waste office paper), physical factors (temperature, pH and time) and biological factor (inoculum size) were examined using two level full factorial design to check the key factors significantly affecting the cellulase production. The central composite design (CCD) was used to optimize the vital fermentation parameters, such as carbon (WOP), nitrogen, pH, and inoculum concentration in the medium for achieving higher cellulase production. The optimum medium composition was found to be WOP (9 g/L), sodium nitrate (0.35 g/L), inoculum size (6.56%) and pH 4.72. The model prediction of 2.46 U/mL cellulase activity at optimum conditions was verified experimentally as 2.42 U/mL.
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Affiliation(s)
- Anu Sadasivan Nair
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman
| | - Huda Al-Battashi
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman
| | - Ahlam Al-Akzawi
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman
| | - Neelamegam Annamalai
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman
| | - Ashish Gujarathi
- Department of Petroleum and Chemical Engineering, Sultan Qaboos University, Muscat, Oman
| | - Saif Al-Bahry
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman
| | | | - Nallusamy Sivakumar
- Department of Biology, College of Science, Sultan Qaboos University, Muscat, Oman.
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24
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Genomically Defined Paenibacillus polymyxa ND24 for Efficient Cellulase Production Utilizing Sugarcane Bagasse as a Substrate. Appl Biochem Biotechnol 2018; 187:266-281. [PMID: 29926286 DOI: 10.1007/s12010-018-2820-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/11/2018] [Indexed: 12/29/2022]
Abstract
Cellulolytic bacteria from cattle rumen with ability to hydrolyze cellulose rich biomass were explored. The study selected Paenibacillus polymyxa ND24 from 847 isolates as the most potent strain, which can efficiently produce cellulase by utilizing sugarcane bagasse, rice straw, corn starch, CMC, and avicel as a sole carbon source. On annotation of P. polymyxa ND24 genome, 116 members of glycoside hydrolase (GH) family from CAZy clusters were identified and the presence of 10 potential cellulases was validated using protein folding information. Cellulase production was further demonstrated at lab-scale 5-L bioreactor exhibiting maximum endoglucanase activity up to 0.72 U/mL when cultivated in the medium containing bagasse (2% w/v) after 72 h. The bagasse hydrolysate so produced was further utilized for efficient biogas production. The presence of diverse hydrolytic enzymes and formidable cellulase activity supports the use of P. polymyxa ND24 for cost-effective bioprocessing of cellulosic biomass.
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25
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Sreena C, Sebastian D. Augmented cellulase production by Bacillus subtilis strain MU S1 using different statistical experimental designs. J Genet Eng Biotechnol 2018; 16:9-16. [PMID: 30647698 PMCID: PMC6296623 DOI: 10.1016/j.jgeb.2017.12.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 12/25/2017] [Accepted: 12/29/2017] [Indexed: 11/23/2022]
Abstract
The production of cellulase by Bacillus subtilis MU S1, a strain isolated from Eravikulam National Park, was optimized using one-factor-at-a-time (OFAT) and statistical methods. Physical parameters like incubation temperature and agitation speed were optimized using OFAT and found to be 40 °C and 150 rpm, respectively, whereas, medium was optimized by statistical tools. Plackett-Burman design (PBD) was employed to screen the significant variables that highly influence cellulase production. The design showed carboxymethyl cellulose (CMC), yeast extract, NaCl, pH, MgSO4 and NaNO3 as the most significant components that affect cellulase production. Among these CMC, yeast extract, NaCl and pH showed positive effect whereas MgSO4 and NaNO3 were found to be significant at their lower levels. The optimum levels of the components that positively affect enzyme production were determined using response surface methodology (RSM) based on central composite design (CCD). Three factors namely CMC, yeast extract and NaCl were studied at five levels whilst pH of the medium was kept constant at 7. The optimal levels of the components were CMC (13.46 g/l), yeast extract (8.38 g/l) and NaCl (6.31 g/l) at pH 7. The maximum cellulase activity in optimized medium was 566.66 U/ml which was close to the predicted activity of 541.05 U/ml. Optimization of physical parameters and medium components showed an overall 3.2-fold increase in activity compared to unoptimized condition (179.06 U/ml).
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Affiliation(s)
| | - Denoj Sebastian
- Department of Life Sciences, University of Calicut, Malappuram, Kerala 673635, India
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26
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Khalili E, Huyop F, Myra Abd Manan F, Wahab RA. Optimization of cultivation conditions in banana wastes for production of extracellular β-glucosidase by Trichoderma harzianum Rifai efficient for in vitro inhibition of Macrophomina phaseolina. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2017.1342562] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Elham Khalili
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Johor Bahru, Malaysia
| | - Fahrul Huyop
- Department of Biotechnology and Medical Engineering, Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Johor Bahru, Malaysia
| | - Fatin Myra Abd Manan
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru, Malaysia
| | - Roswanira Abdul Wahab
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru, Malaysia
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27
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Hussain AA, Abdel-Salam MS, Abo-Ghalia HH, Hegazy WK, Hafez SS. Optimization and molecular identification of novel cellulose degrading bacteria isolated from Egyptian environment. J Genet Eng Biotechnol 2017; 15:77-85. [PMID: 30647644 PMCID: PMC6296635 DOI: 10.1016/j.jgeb.2017.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 02/15/2017] [Accepted: 02/19/2017] [Indexed: 10/29/2022]
Abstract
Cellulase producing bacteria were isolated from both soil and ward poultry, using CMC (carboxymethylcellulose) agar medium and screened by iodine method. Cellulase activity of the isolated bacteria was determined by DNS (dinitrosalicylic) acid method. The highly cellulolytic isolates (BTN7A, BTN7B, BMS4 and SA5) were identified on the basis of Gram staining, morphological cultural characteristics, and biochemical tests. They were also identified with 16S rDNA analysis. The phylogenetic analysis of their 16S rDNA sequence data showed that BTN7B has 99% similarity with Anoxybacillus flavithermus, BMS4 has 99% similarity with Bacillus megaterium, SA5 has 99% homology with Bacillus amyloliquefaciens and BTN7A was 99% similar with Bacillus subtilis. Cellulase production by these strains was optimized by controlling different environmental and nutritional factors such as pH, temperature, incubation period, different volumes of media, aeration rate and carbon source. The cellulase specific activity was calculated in each case. In conclusion four highly cellulolytic bacterial strains were isolated and identified and the optimum conditions for each one for cellulase production were determined. These strains could be used for converting plant waste to more useful compounds.
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Affiliation(s)
- Azhar A. Hussain
- Botany Department, Faculty of Women for Arts, Science and Education, Ain Shams Univ., Egypt
| | | | - Hoda H. Abo-Ghalia
- Botany Department, Faculty of Women for Arts, Science and Education, Ain Shams Univ., Egypt
| | - Wafaa K. Hegazy
- Microbial Genetics Department, National Research Centre, P.O. 12622, Dokki, Giza, Egypt
| | - Safa S. Hafez
- Botany Department, Faculty of Women for Arts, Science and Education, Ain Shams Univ., Egypt
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28
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Korany AH, Ali AE, Essam TM, Megahed SA. Optimization of Cellulase Production by Halobacillus sp. QLS 31 Isolated from Lake Qarun, Egypt. Appl Biochem Biotechnol 2017; 183:189-199. [DOI: 10.1007/s12010-017-2438-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 02/10/2017] [Indexed: 11/28/2022]
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29
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Behera BC, Mishra RR, Singh SK, Dutta SK, Thatoi H. Cellulase fromBacillus licheniformisandBrucellasp. isolated from mangrove soils of Mahanadi river delta, Odisha, India. BIOCATAL BIOTRANSFOR 2016. [DOI: 10.1080/10242422.2016.1212846] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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Goswami R, Mukherjee S, Chakraborty AK, Balachandran S, Sinha Babu SP, Chaudhury S. Optimization of growth determinants of a potent cellulolytic bacterium isolated from lignocellulosic biomass for enhancing biogas production. CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY 2016; 18:1565-1583. [DOI: 10.1007/s10098-016-1141-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
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31
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Poszytek K, Ciezkowska M, Sklodowska A, Drewniak L. Microbial Consortium with High Cellulolytic Activity (MCHCA) for Enhanced Biogas Production. Front Microbiol 2016; 7:324. [PMID: 27014244 PMCID: PMC4791528 DOI: 10.3389/fmicb.2016.00324] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 02/29/2016] [Indexed: 11/26/2022] Open
Abstract
The use of lignocellulosic biomass as a substrate in agricultural biogas plants is very popular and yields good results. However, the efficiency of anaerobic digestion, and thus biogas production, is not always satisfactory due to the slow or incomplete degradation (hydrolysis) of plant matter. To enhance the solubilization of the lignocellulosic biomass various physical, chemical and biological pretreatment methods are used. The aim of this study was to select and characterize cellulose-degrading bacteria, and to construct a microbial consortium, dedicated for degradation of maize silage and enhancing biogas production from this substrate. Over 100 strains of cellulose-degrading bacteria were isolated from: sewage sludge, hydrolyzer from an agricultural biogas plant, cattle slurry and manure. After physiological characterization of the isolates, 16 strains (representatives of Bacillus, Providencia, and Ochrobactrum genera) were chosen for the construction of a Microbial Consortium with High Cellulolytic Activity, called MCHCA. The selected strains had a high endoglucanase activity (exceeding 0.21 IU/mL CMCase activity) and a wide range of tolerance to various physical and chemical conditions. Lab-scale simulation of biogas production using the selected strains for degradation of maize silage was carried out in a two-bioreactor system, similar to those used in agricultural biogas plants. The obtained results showed that the constructed MCHCA consortium is capable of efficient hydrolysis of maize silage, and increases biogas production by even 38%, depending on the inoculum used for methane fermentation. The results in this work indicate that the mesophilic MCHCA has a great potential for application on industrial scale in agricultural biogas plants.
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Affiliation(s)
- Krzysztof Poszytek
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw Warsaw, Poland
| | - Martyna Ciezkowska
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw Warsaw, Poland
| | - Aleksandra Sklodowska
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw Warsaw, Poland
| | - Lukasz Drewniak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw Warsaw, Poland
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32
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First report of a tropical Lysobacter enzymogenes producing bifunctional endoglucanase activity towards carboxymethylcellulose and chitosan. ANN MICROBIOL 2015. [DOI: 10.1007/s13213-015-1170-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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33
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Premalatha N, Gopal NO, Jose PA, Anandham R, Kwon SW. Optimization of cellulase production by Enhydrobacter sp. ACCA2 and its application in biomass saccharification. Front Microbiol 2015; 6:1046. [PMID: 26500615 PMCID: PMC4597110 DOI: 10.3389/fmicb.2015.01046] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/14/2015] [Indexed: 11/13/2022] Open
Abstract
Cellulase finds use in saccharification of lignocellulosic agroresidues to fermentable sugars which can be used for production of commercially important metabolites. This study reports endoglucanase (CMCase) production by Enhydrobacter sp. ACCA2. The CMCase activity of the strain ACCA2 was successively improved by optimization of range of physical and nutritional parameter in a set of non-statistical and statistical experiments. Initial non-statistical selection of carbon source, incubation time, temperature and pH resulted in 1.07 fold increase of CMCase activity. In a subsequent statistical method, response surface methodology, optimization of medium components such as carboxymethylcellulose, peptone, NaCl, MgSO4, K2HPO4, and (NH4)2SO4 yielded further increase up to 2.39 fold CMCase activity. The cellulolytic potential was evaluated in biomass saccharification with different plant materials and the results revealed that the enzyme produced by strain may have significant commercial values for industrial saccharification process. Moreover, this is the first report of cellulase production by an Enhydrobacter spp.
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Affiliation(s)
- Nagaiah Premalatha
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Nellaiappan O Gopal
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Polpass Arul Jose
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Rangasamy Anandham
- Department of Agricultural Microbiology, Agricultural College and Research Institute, Tamil Nadu Agricultural University Madurai, India
| | - Soon-Wo Kwon
- Korean Agricultural Culture Collection, National Academy of Agricultural Science, Rural Development Administration Jeonju, South Korea
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34
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Park AR, Park JH, Ahn HJ, Jang JY, Yu BJ, Um BH, Yoon JJ. Enhancement of β-Glucosidase Activity from a Brown Rot Fungus Fomitopsis pinicola KCTC 6208 by Medium Optimization. MYCOBIOLOGY 2015; 43:57-62. [PMID: 25892916 PMCID: PMC4397381 DOI: 10.5941/myco.2015.43.1.57] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 01/25/2015] [Accepted: 03/02/2015] [Indexed: 05/15/2023]
Abstract
β-Glucosidase, which hydrolyzes cellobiose into two glucoses, plays an important role in the process of saccharification of the lignocellulosic biomass. In this study, we optimized the activity of β-glucosidase of brown-rot fungus Fomitopsis pinicola KCTC 6208 using the response surface methodology (RSM) with various concentrations of glucose, yeast extract and ascorbic acid, which are the most significant nutrients for activity of β-glucosidase. The highest activity of β-glucosidase was achieved 3.02% of glucose, 4.35% of yeast extract, and 7.41% ascorbic acid where ascorbic acid was most effective. The maximum activity of β-glucosidase predicted by the RSM was 15.34 U/mg, which was similar to the experimental value 14.90 U/mg at the 16th day of incubation. This optimized activity of β-glucosidase was 23.6 times higher than the preliminary activity value, 0.63 U/mg, and was also much higher than previous values reported in other fungi strains. Therefore, a simplified medium supplemented with a cheap vitamin source, such as ascorbic acid, could be a cost effective mean of increasing β-glucosidase activity.
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Affiliation(s)
- Ah Reum Park
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
| | - Jeong-Hoon Park
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
| | - Hye-Jin Ahn
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
| | - Ji Yeon Jang
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
| | - Byung Jo Yu
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
| | - Byung-Hwan Um
- Department of Chemical Engineering, Hankyong National University, Anseong 456-749, Korea
| | - Jeong-Jun Yoon
- IT Convergence Materials R&D Group, Chungcheong Regional Division, Korea Institute of Industrial Technology (KITECH), Cheonan 330-825, Korea
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35
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Gupta P, Parkhey P. A two-step process for efficient enzymatic saccharification of rice straw. BIORESOURCE TECHNOLOGY 2014; 173:207-215. [PMID: 25305650 DOI: 10.1016/j.biortech.2014.09.101] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 09/18/2014] [Accepted: 09/19/2014] [Indexed: 05/16/2023]
Abstract
Response surface methodology was used to optimise a two-step process of cellulase mediated saccharification of rice straw by an isolated bacterium Lysinibacillus sphaericus. CMC concentration, yeast extract, pH and incubation temperature were optimised for cellulase production using a central composite design and their optimum values were determined to be 4.3% (w/v), 2.1% (w/v), 6.2 and 45.2 °C respectively. The CMCase activity at these values was 5.16±0.07 U/ml, which was 2.5 times that of the un-optimised system. Similarly, pretreated rice straw, enzyme load, incubation time and Tween-80 concentrations were optimised for enhanced saccharification of rice straw by optimised cellulase preparations, and their optimum values were calculated as 1.84% (w/v), 40 U, 57.4 h and 0.76 mM respectively. A percent saccharification of 69.5% was reported at optimal conditions. HPLC analysis revealed that hydrolysate produced at optimal conditions of saccharification constituted 70.8% of glucose.
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Affiliation(s)
- Pratima Gupta
- Department of Biotechnology, National Institute of Technology, Raipur, C.G. 492010, India.
| | - Piyush Parkhey
- Department of Biotechnology, National Institute of Technology, Raipur, C.G. 492010, India.
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36
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Singh S, Moholkar VS, Goyal A. Optimization of carboxymethylcellulase production from Bacillus amyloliquefaciens SS35. 3 Biotech 2014; 4:411-424. [PMID: 28324477 PMCID: PMC4145630 DOI: 10.1007/s13205-013-0169-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Accepted: 08/26/2013] [Indexed: 11/21/2022] Open
Abstract
In this paper, we have attempted optimization of production of enzyme carboxymethylcellulase or endoglucanase from the bacterium Bacillus amyloliquefaciens SS35. Optimization has been carried out in two stages using statistical experimental design, viz. medium optimization and optimization of fermentation parameters. For medium optimization, Plackett–Burman design followed by central composite design (CCD) was used, while for optimization of fermentation parameters one-variable-at-a-time method followed by CCD was used. Carbon and nitrogen sources in the medium have been revealed to be the significant factors for enzyme production (carboxymethylcellulose 18.05 g/L; yeast extract 8 g/L and peptone 2 g/L). The inorganic salts have been found to be insignificant components of medium. Optimum fermentation parameters for optimized medium were: initial medium pH 5.65, incubation temperature = 40 °C, shaking speed = 120 rpm, and inoculum size = 6.96 %, v/v. Interestingly, the influence of all four parameters was almost independent with no interlinks. Secondly, the overall effect of all parameters was also low, as indicated by linear, square and interaction regression coefficients that were at least one order of magnitude lower than the intercept in the model equation. These results essentially meant that medium components dominate overall enzyme production process in comparison to fermentation parameters.
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37
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Isolation, screening, and identification of cellulolytic bacteria from natural reserves in the subtropical region of China and optimization of cellulase production by Paenibacillus terrae ME27-1. BIOMED RESEARCH INTERNATIONAL 2014; 2014:512497. [PMID: 25050355 PMCID: PMC4090499 DOI: 10.1155/2014/512497] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 05/08/2014] [Indexed: 11/17/2022]
Abstract
From different natural reserves in the subtropical region of China, a total of 245 aerobic bacterial strains were isolated on agar plates containing sugarcane bagasse pulp as the sole carbon source. Of the 245 strains, 22 showed hydrolyzing zones on agar plates containing carboxymethyl cellulose after Congo-red staining. Molecular identification showed that the 22 strains belonged to 10 different genera, with the Burkholderia genus exhibiting the highest strain diversity and accounting for 36.36% of all the 22 strains. Three isolates among the 22 strains showed higher carboxymethyl cellulase (CMCase) activity, and isolate ME27-1 exhibited the highest CMCase activity in liquid culture. The strain ME27-1 was identified as Paenibacillus terrae on the basis of 16S rRNA gene sequence analysis as well as physiological and biochemical properties. The optimum pH and temperature for CMCase activity produced by the strain ME27-1 were 5.5 and 50°C, respectively, and the enzyme was stable at a wide pH range of 5.0–9.5. A 12-fold improvement in the CMCase activity (2.08 U/mL) of ME27-1 was obtained under optimal conditions for CMCase production. Thus, this study provided further information about the diversity of cellulose-degrading bacteria in the subtropical region of China and found P. terrae ME27-1 to be highly cellulolytic.
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38
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Das SP, Ravindran R, Deka D, Jawed M, Das D, Goyal A. Bioethanol production from leafy biomass of mango (Mangifera indica) involving naturally isolated and recombinant enzymes. Prep Biochem Biotechnol 2014; 43:717-34. [PMID: 23768115 DOI: 10.1080/10826068.2013.773342] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The present study describes the usage of dried leafy biomass of mango (Mangifera indica) containing 26.3% (w/w) cellulose, 54.4% (w/w) hemicellulose, and 16.9% (w/w) lignin, as a substrate for bioethanol production from Zymomonas mobilis and Candida shehatae. The substrate was subjected to two different pretreatment strategies, namely, wet oxidation and an organosolv process. An ethanol concentration (1.21 g/L) was obtained with Z. mobilis in a shake-flask simultaneous saccharification and fermentation (SSF) trial using 1% (w/v) wet oxidation pretreated mango leaves along with mixed enzymatic consortium of Bacillus subtilis cellulase and recombinant hemicellulase (GH43), whereas C. shehatae gave a slightly higher (8%) ethanol titer of 1.31 g/L. Employing 1% (w/v) organosolv pretreated mango leaves and using Z. mobilis and C. shehatae separately in the SSF, the ethanol titers of 1.33 g/L and 1.52 g/L, respectively, were obtained. The SSF experiments performed with 5% (w/v) organosolv-pretreated substrate along with C. shehatae as fermentative organism gave a significantly enhanced ethanol titer value of 8.11 g/L using the shake flask and 12.33 g/L at the bioreactor level. From the bioreactor, 94.4% (v/v) ethanol was recovered by rotary evaporator with 21% purification efficiency.
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Affiliation(s)
- Saprativ P Das
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam, India
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Deka D, Jawed M, Goyal A. Purification and characterization of an alkaline cellulase produced by Bacillus subtilis (AS3). Prep Biochem Biotechnol 2013; 43:256-70. [PMID: 23379273 DOI: 10.1080/10826068.2012.719849] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
An extracellular alkaline carboxymethycellulase (CMCase) from Bacillus subtilis was purified by salt precipitation followed by anion-exchange chromatography using DEAE-Sepharose. The cell-free supernatant containing crude enzyme had a CMCase activity of 0.34 U/mg. The purified enzyme gave a specific activity of 3.33 U/mg, with 10-fold purification and an overall activity yield of 5.6%. The purified enzyme displayed a protein band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with an apparent molecular size of 30 kDa, which was also confirmed by zymogram analysis. The enzyme displayed multisubstrate specificity, showing significantly higher activity with lichenan and β-glucan as compared to carboxymethylcellulose (CMC), laminarin, hydroxyethylcellulose, and steam-exploded bagasse, and negligible activity with crystalline substrate such as Avicel and filter paper. It was optimally active at pH 9.2 and temperature 45°C. The enzyme was stable in the pH range 6-10 and retained 70% activity at pH 12. Thermal stability analysis revealed that the enzyme was stable in temperature range of 20°C to 45°C and retained more than 50% activity at 60°C for 30 min. The enzyme had a Km of 0.13 mg/ml and Vmax of 3.38 U/mg using CMC as substrate.
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Affiliation(s)
- Deepmoni Deka
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati, Assam, India
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Isolation, Identification, and Characterization of a Cellulolytic Bacillus amyloliquefaciens Strain SS35 from Rhinoceros Dung. ISRN MICROBIOLOGY 2013; 2013:728134. [PMID: 23762763 PMCID: PMC3676922 DOI: 10.1155/2013/728134] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 05/08/2013] [Indexed: 11/17/2022]
Abstract
Cellulose hydrolyzing bacteria were isolated from rhinoceros dung and tested for clear zone formation around the colonies on the agar plates containing the medium amended with carboxymethylcellulose as a sole carbon source. Isolates were further screened on the basis of carboxymethylcellulase production in liquid medium. Out of 36 isolates, isolate no. 35 exhibited maximum enzyme activity of 0.079 U/mL and was selected for further identification by using conventional biochemical tests and phylogenetic analyses. This was a Gram-positive, spore forming bacterium with rod-shaped cells. The isolate was identified as Bacillus amyloliquefaciens SS35 based on nucleotide homology and phylogenetic analysis using 16S rDNA and gyrase A gene sequences.
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Deka D, Das SP, Sahoo N, Das D, Jawed M, Goyal D, Goyal A. Enhanced Cellulase Production from Bacillus subtilis by Optimizing Physical Parameters for Bioethanol Production. ISRN BIOTECHNOLOGY 2013; 2013:965310. [PMID: 25937985 PMCID: PMC4393054 DOI: 10.5402/2013/965310] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 01/12/2013] [Indexed: 11/30/2022]
Abstract
Effect of physical parameters such as initial pH, agitation (rpm), and temperature (°C) for cellulase production from Bacillus subtilis AS3 was investigated. Central composite design of experiments followed by multiple desirability function was applied for the optimization of cellulase activity and cell growth. The effect of the temperature and agitation was found to be significant among the three independent variables. The optimum levels of initial pH, temperature, and agitation for alkaline carboxymethylcellulase (CMCase) production predicted by the model were 7.2, 39°C, and 121 rpm, respectively. The CMCase activity with unoptimized physical parameters and previously optimized medium composition was 0.43 U/mL. The maximum activity (0.56 U/mL) and cell growth (2.01 mg/mL) predicted by the model were in consensus with values (0.57 U/mL, 2.1 mg/mL) obtained using optimized medium and optimal values of physical parameters. After optimization, 33% enhancement in CMCase activity (0.57 U/mL) was recorded. On scale-up of cellulase production process in bioreactor with all the optimized conditions, an activity of 0.75 U/mL was achieved. Consequently, the bacterial cellulase employed for bioethanol production expending (5%, w/v) NaOH-pretreated wild grass with Zymomonas mobilis yielded an utmost ethanol titre of 7.56 g/L and 11.65 g/L at shake flask and bioreactor level, respectively.
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Affiliation(s)
- Deepmoni Deka
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Saprativ P Das
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Naresh Sahoo
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Debasish Das
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Mohammad Jawed
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Dinesh Goyal
- Department of Biotechnology and Environmental Sciences, Thapar University, Patiala, Punjab 147004, India
| | - Arun Goyal
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India ; Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
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Hao T, Han B, Ma H, Fu J, Wang H, Wang Z, Tang B, Chen T, Zhao X. In silico metabolic engineering of Bacillus subtilis for improved production of riboflavin, Egl-237, (R,R)-2,3-butanediol and isobutanol. MOLECULAR BIOSYSTEMS 2013; 9:2034-44. [DOI: 10.1039/c3mb25568a] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Shivanand P, Mugeraya G, Kumar A. Utilization of renewable agricultural residues for the production of extracellular halostable cellulase from newly isolated Halomonas sp. strain PS47. ANN MICROBIOL 2012. [DOI: 10.1007/s13213-012-0583-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Dissecting structure–function–stability relationships of a thermostable GH5-CBM3 cellulase from Bacillus subtilis 168. Biochem J 2011; 441:95-104. [DOI: 10.1042/bj20110869] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Cellulases participate in a number of biological events, such as plant cell wall remodelling, nematode parasitism and microbial carbon uptake. Their ability to depolymerize crystalline cellulose is of great biotechnological interest for environmentally compatible production of fuels from lignocellulosic biomass. However, industrial use of cellulases is somewhat limited by both their low catalytic efficiency and stability. In the present study, we conducted a detailed functional and structural characterization of the thermostable BsCel5A (Bacillus subtilis cellulase 5A), which consists of a GH5 (glycoside hydrolase 5) catalytic domain fused to a CBM3 (family 3 carbohydrate-binding module). NMR structural analysis revealed that the Bacillus CBM3 represents a new subfamily, which lacks the classical calcium-binding motif, and variations in NMR frequencies in the presence of cellopentaose showed the importance of polar residues in the carbohydrate interaction. Together with the catalytic domain, the CBM3 forms a large planar surface for cellulose recognition, which conducts the substrate in a proper conformation to the active site and increases enzymatic efficiency. Notably, the manganese ion was demonstrated to have a hyper-stabilizing effect on BsCel5A, and by using deletion constructs and X-ray crystallography we determined that this effect maps to a negatively charged motif located at the opposite face of the catalytic site.
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