1
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Ruan L, Wu H, Wu S, Zhou L, Wu S, Shang C. Optimizing the Conditions of Pretreatment and Enzymatic Hydrolysis of Sugarcane Bagasse for Bioethanol Production. ACS OMEGA 2024; 9:29566-29575. [PMID: 39005808 PMCID: PMC11238294 DOI: 10.1021/acsomega.4c02485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/16/2024]
Abstract
The agricultural waste sugarcane bagasse (SCB) is a kind of plentiful biomass resource. In this study, different pretreatment methods (NaOH, H2SO4, and sodium percarbonate/glycerol) were utilized and compared. Among the three pretreatment methods, NaOH pretreatment was the most optimal method. Response surface methodology (RSM) was utilized to optimize NaOH pretreatment conditions. After optimization by RSM, the solid yield and lignin removal were 54.60 and 82.30% under the treatment of 1% NaOH, a time of 60 min, and a solid-to-liquid ratio of 1:15, respectively. Then, the enzymolysis conditions of cellulase for NaOH-treated SCB were optimized by RSM. Under the optimal enzymatic hydrolysis conditions (an enzyme dose of 18 FPU/g, a time of 64 h, and a solid-to-liquid ratio of 1:30), the actual yield of reducing sugar in the enzyme-treated hydrolysate was 443.52 mg/g SCB with a cellulose conversion rate of 85.33%. A bacterium, namely, Bacillus sp. EtOH, which produced ethanol and Baijiu aroma substances, was isolated from the high-temperature Daqu of Danquan Baijiu in our previous study. At last, when the strain EtOH was cultured for 36 h in a fermentation medium (reducing sugar from cellulase-treated SCB hydrolysate, yeast extract, and peptone), ethanol concentration reached 2.769 g/L (0.353%, v/v). The sugar-to-ethanol and SCB-to-ethanol yields were 13.85 and 11.81% in this study, respectively. In brief, after NaOH pretreatment, 1 g of original SCB produced 0.5460 g of NaOH-treated SCB. Then, after the enzymatic hydrolysis, reducing sugar yield (443.52 mg/g SCB) was obtained. Our study provided a suitable method for bioethanol production from SCB, which achieved efficient resource utilization of agricultural waste SCB.
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Affiliation(s)
- Lingru Ruan
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
| | - Haifeng Wu
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
| | - Shiya Wu
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
| | - Lifei Zhou
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
| | - Shangxin Wu
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
| | - Changhua Shang
- Key Laboratory of Ecology
of Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education & Guangxi Key Laboratory
of Landscape Resources Conservation and Sustainable Utilization in
Lijiang River Basin, Guangxi Normal University, Guilin 541006, China
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Ejaz U, Shafquat Y, Sohail M, Shaikh AA, Arain MD, Ahmed T, Alanazi AK. Extraction of cellulose from halophytic plants for the synthesis of a novel biocomposite. Biopolymers 2024; 115:e23586. [PMID: 38747448 DOI: 10.1002/bip.23586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/16/2024] [Accepted: 04/29/2024] [Indexed: 07/16/2024]
Abstract
Cellulose nanofibers, a sustainable and promising material with widespread applications, exhibit appreciable strength and excellent mechanical and physicochemical properties. The preparation of cellulosic nanofibers from food or agricultural residue is not sustainable. Therefore, this study was designed to use three halophytic plants (Cressa cretica, Phragmites karka, and Suaeda fruticosa) to extract cellulose for the subsequent conversion to cellulosic nanofibers composites. The other extracted biomass components including lignin, hemicellulose, and pectin were also utilized to obtain industrially valuable enzymes. The maximum pectinase (31.56 IU mL-1), xylanase (35.21 IU mL-1), and laccase (15.89 IU mL-1) were produced after the fermentation of extracted pectin, hemicellulose, and lignin from S. fruticosa, P. karka, and C. cretica, respectively. Cellulose was methylated (with a degree of substitution of 2.4) and subsequently converted into a composite using polyvinyl alcohol. Scanning electron microscopy and Fourier-transform infrared spectroscopy confirmed the successful synthesis of the composites. The composites made up of cellulose from C. cretica and S. fruticosa had a high tensile strength (21.5 and 15.2 MPa) and low biodegradability (47.58% and 44.56%, respectively) after dumping for 3 months in soil, as compared with the composite from P. karka (98.79% biodegradability and 4.9 MPa tensile strength). Moreover, all the composites exhibited antibacterial activity against gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) and gram-positive bacteria (Staphylococcus aureus). Hence, this study emphasizes the possibility for various industrial applications of biomass from halophytic plants.
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Affiliation(s)
- Uroosa Ejaz
- Department of Biosciences, Faculty of Life Sciences, SZABIST University, Karachi, Pakistan
| | - Yusra Shafquat
- Department of Pathology, Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Aizaz Ahmed Shaikh
- Department of Biosciences, Faculty of Life Sciences, SZABIST University, Karachi, Pakistan
| | - Muhammad Daniyal Arain
- Department of Biosciences, Faculty of Life Sciences, SZABIST University, Karachi, Pakistan
| | - Tehmees Ahmed
- Department of Biosciences, Faculty of Life Sciences, SZABIST University, Karachi, Pakistan
| | - Abdullah K Alanazi
- Department of Chemistry, College of Science, Taif University, Taif, Saudi Arabia
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3
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Ejaz U, Taj A, Sohail M, Alanazi AK, Abo-Dief HM. Toward a zero waste approach: Utilization of sugarcane bagasse for dye removal and multienzymes production. J Basic Microbiol 2024; 64:e2300529. [PMID: 38066405 DOI: 10.1002/jobm.202300529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/02/2023] [Accepted: 11/21/2023] [Indexed: 02/13/2024]
Abstract
Global production of sugarcane bagasse (SB) by sugar industries exceeds more than 100 tons per annum. SB is rich in lignin and polysaccharide and hence can serve as a low-cost energy and carbon source for the growth of industrially important microorganism. However, various other applications of SB have also been investigated. In this study, SB was used as an adsorbent to remove an azo dye, malachite green. Subsequently, the dye-adsorbed SB was fermented by Trametes pubescens MB 89 for the production of laccase enzyme. The fungal pretreated SB was further utilized as a substrate for the simultaneous production of multiple plant cell wall degrading enzymes including, cellulase, xylanase, pectinase, and amylase by thermophilic bacterial strains. Results showed that 0.1% SB removed 97.04% malachite green at 30°C after 30 min from a solution containing 66 ppm of the dye. Fermentation of the dye-adsorbed SB by T. pubescens MB 89 yielded 667.203 IU mL-1 laccase. Moreover, Brevibacillus borstelensis UE10 produced 38.41 and 18.6 IU mL-1 β-glucosidase and pectinase, respectively, by using fungal-pretreated SB. Cultivation of B. borstelensis UE27 in the medium containing the same substrate yielded 32.14 IU mL-1 of endoglucanase and 27.23 IU mL-1 of β-glucosidase. Likewise, Neobacillus sedimentimangrovi UE25 could produce a mix of β-glucosidase (37.24 IU mL-1 ), xylanase (18.65 IU mL-1 ) and endoglucanase (26.65 IU mL-1 ). Hence, this study led to the development of a method through which dye-containing textile effluent can be treated by SB along with the production of industrially important enzymes.
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Affiliation(s)
- Uroosa Ejaz
- Department of Biosciences, Faculty of Life Sciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology (Szabist University), Karachi, Pakistan
| | - Ayaz Taj
- Sindh Institute of Urology and Transplantation, Karachi, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | | | - Hala M Abo-Dief
- Department of Science and Technology, University College-Ranyah, Taif University, Taif, Saudi Arabia
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Ejaz U, Saleem F, Rashid R, Hasan KA, Syed MN, Sohail M. Unveiling the genomic potential of a novel thermostable glycoside hydrolases producing Neobacillus sedimentimangrovi UE25. Antonie Van Leeuwenhoek 2023:10.1007/s10482-023-01835-y. [PMID: 37140754 DOI: 10.1007/s10482-023-01835-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 04/24/2023] [Indexed: 05/05/2023]
Abstract
Genetic and enzymatic potential of Neobacillus sedimentimangrovi has not been assembled to date. Here, we report a high-quality genome assembly of thermophilic bacterium Neobacillus sedimentimangrovi UE25 using Illumina Hi-seq 2500. The strain was isolated from a crocodile pond Manghopir, Karachi, Pakistan. QUAST quality parameters showed 37.75% GC content and exhibited the genome into 110 contigs, with a total size of 3,230,777 bases. Genome of N. sedimentimangrovi UE25 harbors phage mediated DNA through horizontal gene exchange from the phages, symbiotic and pathogenic bacteria. Most of the phage genome encodes for hypothetical proteins, protease, and phage assembly proteins. Gene clusters encoding the intrinsic resistance to glycopeptides, isoniazid, rifamycin, elfamycin, macrolide, aminoglycosides, tetracycline and fluoroquinolone were identified into the genome. Since, the strain has been reported for the production of many industrially important thermostable enzymes, therefore, the genomic data of thermostable enzymes might be helpful to employ this species in commercial sectors. Probing genes of multiple thermostable glycoside hydrolase enzymes especially xylanases of N. sedimentimangrovi UE25 showed genetic diversity among the genes and confer the industrial importance of this microorganism. Furthermore, the genome of N. sedimentimangrovi will greatly improve our understanding of its genetics and evolution.
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Affiliation(s)
- Uroosa Ejaz
- Department of Biosciences, Faculty of Life Sciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology (SZABIST), Karachi, 75600, Pakistan
- Department of Microbiology, University of Karachi, Karachi, 75600, Pakistan
| | - Faizan Saleem
- Department of Biology, McMaster University, Hamilton, ON, L8S 4L8, Canada
| | - Rozina Rashid
- Department of Microbiology, University of Karachi, Karachi, 75600, Pakistan
- Department of Microbiology, University of Balochistan, Quetta, Pakistan
| | - Khwaja Ali Hasan
- Molecular and Structural Biology Research Unit, Department of Biochemistry, University of Karachi, Karachi, 75270, Pakistan
| | - Muhammad Noman Syed
- Nutritional Biochemistry Research Unit, Department of Biochemistry, University of Karachi, Karachi, 75270, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, 75600, Pakistan.
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Abbas M, Ejaz U, Shafique M, Naz SA, Sohail M. Biological pretreatment of sugarcane bagasse for the production of fungal laccase and bacterial cellulase. J Basic Microbiol 2023. [PMID: 36856084 DOI: 10.1002/jobm.202200684] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/15/2023] [Accepted: 02/19/2023] [Indexed: 03/02/2023]
Abstract
Sugarcane bagasse (SB) is a promising source of appreciable quantities of fermentable sugars. However, the presence of lignin hinders utilization of these carbohydrates and hence pretreatment to remove lignin is necessarily carried out. Here, a biological pretreatment method was synchronized with the production of a thermostable cellulase using SB as a raw material. Initially, bagasse was fermented by a laccase producing fungus, Trametes pubescens MB 89 under solid state fermentation (SSF) and a titer of 1758 IU mL-1 of laccase was obtained. Investigations of nine factors affecting laccase production through Plackett Burman design improved the titers to 6539 IU mL-1 . Five factors (incubation period, concentration of CuSO4 , temperature, moisture content, and particle size) were found significant which were optimized through Central Composite design leading to an improvement in the titers by ~5 folds (8841 IU mL-1 ). Biologically pretreated SB was fermented by a thermophilic bacterium, Neobacillus sedimentimangrovi UE25, that yielded 8.64 IU mL-1 of cellulase. Delignification and cellulose utilization were affirmed by structural analysis through FTIR and SEM. The synchronized process yielded higher titers of laccase and cellulase under SSF of SB with the minimum use of corrosive chemicals.
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Affiliation(s)
- Mustansir Abbas
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Uroosa Ejaz
- Department of Biosciences, Faculty of Life Sciences, Shaheed Zulfiqar Ali Bhutto Institute of Science and Technology (SZABIST), Karachi, Pakistan
| | - Maryam Shafique
- Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Karachi, Pakistan
| | - Sehar A Naz
- Department of Microbiology, Federal Urdu University of Arts, Science and Technology, Karachi, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan
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Characterization of a novel end product tolerant and thermostable cellulase from Neobacillus sedimentimangrovi UE25. Enzyme Microb Technol 2023; 162:110133. [DOI: 10.1016/j.enzmictec.2022.110133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 09/10/2022] [Accepted: 09/13/2022] [Indexed: 10/14/2022]
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El Harrar T, Davari MD, Jaeger KE, Schwaneberg U, Gohlke H. Critical assessment of structure-based approaches to improve protein resistance in aqueous ionic liquids by enzyme-wide saturation mutagenesis. Comput Struct Biotechnol J 2022; 20:399-409. [PMID: 35070165 PMCID: PMC8752993 DOI: 10.1016/j.csbj.2021.12.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 12/10/2021] [Accepted: 12/11/2021] [Indexed: 12/12/2022] Open
Abstract
Ionic liquids (IL) and aqueous ionic liquids (aIL) are attractive (co-)solvents for green industrial processes involving biocatalysts, but often reduce enzyme activity. Experimental and computational methods are applied to predict favorable substitution sites and, most often, subsequent site-directed surface charge modifications are introduced to enhance enzyme resistance towards aIL. However, almost no studies evaluate the prediction precision with random mutagenesis or the application of simple data-driven filtering processes. Here, we systematically and rigorously evaluated the performance of 22 previously described structure-based approaches to increase enzyme resistance to aIL based on an experimental complete site-saturation mutagenesis library of Bacillus subtilis Lipase A (BsLipA) screened against four aIL. We show that, surprisingly, most of the approaches yield low gain-in-precision (GiP) values, particularly for predicting relevant positions: 14 approaches perform worse than random mutagenesis. Encouragingly, exploiting experimental information on the thermostability of BsLipA or structural weak spots of BsLipA predicted by rigidity theory yields GiP = 3.03 and 2.39 for relevant variants and GiP = 1.61 and 1.41 for relevant positions. Combining five simple-to-compute physicochemical and evolutionary properties substantially increases the precision of predicting relevant variants and positions, yielding GiP = 3.35 and 1.29. Finally, combining these properties with predictions of structural weak spots identified by rigidity theory additionally improves GiP for relevant variants up to 4-fold to ∼10 and sustains or increases GiP for relevant positions, resulting in a prediction precision of ∼90% compared to ∼9% in random mutagenesis. This combination should be applicable to other enzyme systems for guiding protein engineering approaches towards improved aIL resistance.
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Affiliation(s)
- Till El Harrar
- Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Mehdi D. Davari
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, 06120 Halle, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, 52428 Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
| | - Ulrich Schwaneberg
- Institute of Biotechnology, RWTH Aachen University, 52074 Aachen, Germany
- DWI – Leibniz Institute for Interactive Materials e.V., 52074 Aachen, Germany
| | - Holger Gohlke
- John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, 52428 Jülich, Germany
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
- Corresponding author at: John-von-Neumann-Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany.
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Statistical optimization of saccharificaion of carbohydrate content of alkali pretreated sugarcane bagasse by enzyme cocktail produced by Bacillus vallismortis MH 1 and Bacillus aestuarii UE25. CARBOHYDRATE POLYMER TECHNOLOGIES AND APPLICATIONS 2021. [DOI: 10.1016/j.carpta.2021.100174] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Ren W, Xu X, Long H, Zhang X, Cai X, Huang A, Xie Z. Tropical Cellulolytic Bacteria: Potential Utilization of Sugarcane Bagasse as Low-Cost Carbon Source in Aquaculture. Front Microbiol 2021; 12:745853. [PMID: 34777293 PMCID: PMC8586208 DOI: 10.3389/fmicb.2021.745853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/07/2021] [Indexed: 11/13/2022] Open
Abstract
Sugarcane bagasse (SB), as a major by-product of sugarcane, is one of the most abundant organic matter and characterized by cheap and easily available carbon source in Hainan Island, China. The objective of this study was to isolate tropical cellulolytic bacteria from Hainan Island and demonstrate their prospects of utilization of SB as a low-cost carbon source to greatly reduce the cost of aquaculture. A total of 97 cellulolytic marine bacteria were isolated, of which, 58 cellulolytic marine bacteria displayed the hydrolysis capacity (HC) of more than 1, while 28 cellulolytic marine bacteria displayed more than 2. Of the 28 tropical cellulolytic bacterial strains with HC more than 2, Microbulbifer sp. CFW-C18 and Vibrio sp. MW-M19 exhibited excellent SB decomposition in a small-scale laboratory simulation of shrimp aquaculture, up to 75.31 and 74.35%, respectively, and both of them were safe for shrimps. Meanwhile, both of CFW-C18 and MW-M19 besides displaying low multiple antibiotic resistance (MAR) index, also increased the C/N ratio (CFW-C18: C/N ratio of 14.34; MW-M19: C/N ratio of 14.75) of the small-scale laboratory simulation of shrimp aquaculture by decreasing the nitrogen content after a supplement of SB for 15 days. More importantly, CFW-C18 and MW-M19 displayed a relatively low MAR index, 0.47 and 0.1, respectively, especially MW-M19, with the lowest MAR index (0.1), which was resistant to only three antibiotics, streptomycin, amikacin, and levofloxacin, indicating that this strain was safe and non-drug resistance for further use. Overall, tropical cellulolytic bacteria isolated from Hainan Island, especially CFW-C18 and MW-M19, will provide the proficient candidates as probiotics for further construction of the recirculating aquaculture system based on the supplement of low-cost external carbon source—SB.
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Affiliation(s)
- Wei Ren
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Xueni Xu
- Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China
| | - Hao Long
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Xiang Zhang
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Xiaoni Cai
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Aiyou Huang
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
| | - Zhenyu Xie
- State Key Laboratory of Marine Resource Utilization in the South China Sea, Hainan University, Haikou, China.,Hainan Provincial Key Laboratory for Tropical Hydrobiology and Biotechnology, Hainan University, Haikou, China.,College of Marine Sciences, Hainan University, Haikou, China.,Laboratory of Development and Utilization of Marine Microbial Resource, Hainan University, Haikou, China
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Ejaz U, Wasim AA, Khan MN, Alzahrani OM, Mahmoud SF, El-Bahy ZM, Sohail M. Use of Ionic Liquid Pretreated and Fermented Sugarcane Bagasse as an Adsorbent for Congo Red Removal. Polymers (Basel) 2021; 13:polym13223943. [PMID: 34833242 PMCID: PMC8622147 DOI: 10.3390/polym13223943] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/10/2021] [Accepted: 11/12/2021] [Indexed: 11/16/2022] Open
Abstract
A large amount of industrial wastewater containing pollutants including toxic dyes needs to be processed prior to its discharge into the environment. Biological materials such as sugarcane bagasse (SB) have been reported for their role as adsorbents to remove the dyes from water. In this study, the residue SB after fermentation was utilized for the dye removal. A combined pretreatment of NaOH and methyltrioctylammonium chloride was given to SB for lignin removal, and the pretreated SB was utilized for cellulase production from Bacillus aestuarii UE25. The strain produced 118 IU mL-1 of endoglucanse and 70 IU mL-1 of β-glucosidase. Scanning electron microscopy and FTIR spectra showed lignin and cellulose removal in fermented SB. This residue was utilized for the adsorption of an azo dye, congo red (CR). The thermodynamic, isotherm and kinetics studies for the adsorption of CR revealed distinct adsorption features of SB. Untreated SB followed Langmuir isotherm, whereas pretreated SB and fermented SB obeyed the Freundlich isotherm model. The pseudo-second-order model fitted well for the studied adsorbents. The results of thermodynamic studies revealed spontaneous adsorption with negative standard free energy values. Untreated SB showed a 90.36% removal tendency at 303.15 K temperature, whereas the adsorbents comprised of pretreated and fermented SB removed about 98.35% and 97.70%, respectively. The study provided a strategy to utilize SB for cellulase production and its use as an adsorbent for toxic dyes removal.
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Affiliation(s)
- Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi 75270, Pakistan;
- Department of Biosciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology (SZABIST), Karachi 75600, Pakistan
| | - Agha Arslan Wasim
- Department of Chemistry, University of Karachi, Karachi 75270, Pakistan; (A.A.W.); (M.N.K.)
| | | | - Othman M. Alzahrani
- Department of Biology College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;
| | - Samy F. Mahmoud
- Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;
| | - Zeinhom M. El-Bahy
- Department of Chemistry, Faculty of Science, Al-Azhar University, Cairo 11884, Egypt;
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi 75270, Pakistan;
- Correspondence:
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Rajamani S, Santhosh R, Raghunath R, Jadhav SA. Value-added chemicals from sugarcane bagasse using ionic liquids. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-021-01732-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Ansari I, Ejaz U, Abideen Z, Gulzar S, Syed MN, Liu J, Li W, Fu P, Sohail M. Wild Halophytic Phragmites karka Biomass Saccharification by Bacterial Enzyme Cocktail. Front Microbiol 2021; 12:714940. [PMID: 34616380 PMCID: PMC8488365 DOI: 10.3389/fmicb.2021.714940] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
Biofuel derived from halophytic biomass is getting attention owing to the concerns of energy versus food crisis. The disadvantages associated with edible bioenergy resources necessitate the need to explore new feedstocks for sustainable biofuel production. In this study, biomass from locally available abundant halophytes (Panicum antidotale, Phragmites karka, Halopyrum mucronatum, and Desmostachya bipinnata) was screened for saccharification by an enzyme cocktail composed of cellulase, xylanase, and pectinase from Brevibacillus borstelensis UE10 and UE27, Bacillus aestuarii UE25, Aneurinibacillus thermoaerophilus UE1, and Bacillus vallismortis MH 1. Two types of pretreatment, i.e., with dilute acid and freeze-thaw, were independently applied to the halophytic biomass. Saccharification of acid-pretreated P. karka biomass yielded maximum reducing sugars (9 mg g-1) as compared to other plants. Thus, the factors (temperature, pH, substrate concentration, and enzyme units) affecting its saccharification were optimized using central composite design. This statistical model predicted 49.8 mg g-1 of reducing sugars that was comparable to the experimental value (40 mg g-1). Scanning electron microscopy and Fourier-transform infrared spectroscopy showed significant structural changes after pretreatment and saccharification. Therefore, halophytes growing in saline, arid, and semi-arid regions can be promising alternative sources for bioenergy production.
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Affiliation(s)
- Immad Ansari
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi, Pakistan.,Department of Biosciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology, Karachi, Pakistan
| | - Zainul Abideen
- Dr. Muhammad Ajmal Khan Institute of Sustainable Halophyte Utilization, University of Karachi, Karachi, Pakistan
| | - Salman Gulzar
- Dr. Muhammad Ajmal Khan Institute of Sustainable Halophyte Utilization, University of Karachi, Karachi, Pakistan
| | | | - Jing Liu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Wang Li
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China
| | - Pengcheng Fu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, China.,Weihai UIC Biotechnology, Inc., Weihai, China
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan.,Weihai UIC Biotechnology, Inc., Weihai, China
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13
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Zafar H, Rehman I, Ejaz U, Ansari A, Sohail M. Production of multienzyme by Bacillus aestuarii UE25 using ionic liquid pretreated sugarcane bagasse. J Basic Microbiol 2021; 61:1016-1028. [PMID: 34463967 DOI: 10.1002/jobm.202100323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 08/12/2021] [Accepted: 08/21/2021] [Indexed: 11/05/2022]
Abstract
The utilization of sugarcane bagasse (SB) in fermentation requires pretreatment processes to render fermentable components available to microorganisms. Pretreatment by using ionic liquids (ILs) is considered promising but the high cost is an impediment in its adoption, therefore, a mixture of IL pretreated and untreated SB was utilized to obtain bacterial multienzyme under solid-state fermentation (SSF). Bacillus aestuarii UE25, a thermophilic strain was utilized for that purpose. Fermentation conditions were optimized by adopting a central composite design. The model showed a good correlation between the predicted and the experimental values for amylase, xylanase, endoglucanase, and β-glucosidase. Volumetric and specific productivity of xylanase (4580 IU ml-1 h-1 , 244.25 IU mg-1 substrate, and 50 IU mg-1 protein) were higher than the other enzymes. Changes in lignin content and reduced cellulose crystallinity due to IL pretreatment, followed by fermentation, were visualized by scanning electron microscopy, Fourier transform infrared spectroscopy, and Nuclear magnetic resonance. The strategy adopted by utilizing a mixture of IL pretreated and untreated SB under SSF proved promising to obtain high titers of different enzymes simultaneously. Since the bacterial strain used is thermophilic, therefore, the multienzyme can find its application in commercial processes which are carried out at high temperatures.
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Affiliation(s)
- Hani Zafar
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Iqra Rehman
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi, Pakistan.,Department of Biosciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology (SZABIST), Karachi, Pakistan
| | - Asma Ansari
- The Karachi Institute of Biotechnology and Genetic Engineering, University of Karachi, Karachi, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan
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14
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Ejaz U, Sohail M, Ghanemi A. Cellulases: From Bioactivity to a Variety of Industrial Applications. Biomimetics (Basel) 2021; 6:44. [PMID: 34287227 PMCID: PMC8293267 DOI: 10.3390/biomimetics6030044] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/20/2021] [Accepted: 06/30/2021] [Indexed: 11/16/2022] Open
Abstract
Utilization of microbial enzymes has been widely reported for centuries, but the commercial use of enzymes has been recently adopted. Particularly, cellulases have been utilized in various commercial sectors including agriculture, brewing, laundry, pulp and paper and textile industry. Cellulases of microbial origin have shown their potential application in various commercial sectors including textile, pulp and paper, laundry, brewing, agriculture and biofuel. Cellulases have diversified applications in the food industry, food service, food supply and its preservation. Indeed, cellulases can tenderize fruits, clarify the fruit juices, reduce roughage in dough, hydrolyze the roasted coffee, extract tea polyphenols and essential oils from olives and can increase aroma and taste in food items. However, their role in food industries has by and large remained neglected. The use of immobilized cellulases has further expanded their application in fruit and vegetable processing as it potentiates the catalytic power and reduces the cost of process. Technological and scientific developments will further expand their potential usage in the food industry.
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Affiliation(s)
- Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi 75270, Pakistan;
- Department of Biosciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology (SZABIST), Karachi 75600, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi 75270, Pakistan;
| | - Abdelaziz Ghanemi
- Department of Molecular Medicine, Faculty of Medicine, Laval University, Quebec, QC G1V 0A6, Canada
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15
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Ejaz U, Sohail M. Supporting role of lignin in immobilization of yeast on sugarcane bagasse for continuous pectinase production. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:1709-1714. [PMID: 32844441 DOI: 10.1002/jsfa.10764] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/20/2020] [Accepted: 08/26/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Lignocellulosic wastes are pretreated prior to their utilization in fermentation processes. Such pretreatment also alters the topological features of the substrates, and therefore the suitability of pretreated waste as immobilization matrix for microbial cells needs investigation. RESULTS In this study, the effect of chemical pretreatment of sugarcane bagasse (SB) for its subsequent utilization as a matrix to immobilize a pectinolytic yeast, Geotrichum candidum AA15, was evaluated using cell retention, concentration of immobilized cells, immobilization efficiency, scanning electron microscopy and Fourier transform infrared spectroscopy of the substrate and pectinase titers obtained after recycling. The results revealed that untreated SB is more efficient for immobilization with higher values of cell retention and pectinase productivity (99.78%) retained for up to six production cycles. It was deduced that removal of lignin by pretreatment negatively influenced the ability of SB to support cell adhesion, as lignin acts as a sealing agent that provides strength to the substrate. CONCLUSIONS The strategy of utilizing SB as immobilization matrix was found effective at the laboratory scale as it improved pectinase production and may be investigated further for large-scale and cost-effective production. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan
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16
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Ejaz U, Muhammad S, Ali FI, Hashmi IA, Sohail M. Cellulose extraction from methyltrioctylammonium chloride pretreated sugarcane bagasse and its application. Int J Biol Macromol 2020; 165:11-17. [PMID: 32987070 DOI: 10.1016/j.ijbiomac.2020.09.151] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 08/26/2020] [Accepted: 09/20/2020] [Indexed: 10/23/2022]
Abstract
Cellulose, the most abundant feedstock of chemicals and energy is extracted from various agro-industrial wastes, such as sugarcane bagasse (SB). Pretreatment of SB with ionic liquids improves extraction of cellulose, yet the use of ionic liquid is hindered by its high cost. In this study, cellulose was extracted from SB pretreated with methyltrioctylammonium chloride under relatively mild conditions. The extracted cellulose from pretreated SB (PTB) and untreated SB (UTB) was characterized by scanning electron microscopy and FTIR. Fermentation of cellulose extracted from PTB by a thermophilic bacterium, Bacillus aestuarii UE25, yielded 245.16% higher titers of cellulase than cellulose extracted from UTB. The recyclability of the IL was assessed to make the pretreatment process cost effective and was monitored through TLC and FTIR. The results of this research demonstrated the potential of ionic liquid pretreated SB for cellulose extraction and for its subsequent utilization in thermostable cellulase production.
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Affiliation(s)
- Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi, Pakistan
| | - Shoaib Muhammad
- Department of Chemistry, University of Karachi, Karachi, Pakistan
| | | | - Imran Ali Hashmi
- Department of Chemistry, University of Karachi, Karachi, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, Pakistan.
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17
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Rashid R, Ejaz U, Ali FI, Hashmi IA, Bari A, Liu J, Wang L, Fu P, Sohail M. Combined pretreatment of sugarcane bagasse using alkali and ionic liquid to increase hemicellulose content and xylanase production. BMC Biotechnol 2020; 20:64. [PMID: 33298027 PMCID: PMC7724814 DOI: 10.1186/s12896-020-00657-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/11/2020] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Lignin in sugarcane bagasse (SB) hinders its utilization by microorganism, therefore, pretreatment methods are employed to make fermentable components accessible to the microbes. Multivariate analysis of different chemical pretreatment methods can aid to select the most appropriate strategy to valorize a particular biomass. RESULTS Amongst methods tested, the pretreatment by using sodium hydroxide in combination with methyltrioctylammonium chloride, an ionic liquid, (NaOH+IL) was the most significant for xylanase production by Bacillus aestuarii UE25. Investigation of optimal levels of five significant variables by adopting Box-Behnken design (BBD) predicted 20 IU mL- 1 of xylanase and experimentally, a titer of 17.77 IU mL- 1 was obtained which indicated the validity of the model. The production kinetics showed that volumetric productivity of xylanase was much higher after 24 h (833.33 IU L- 1 h- 1) than after 48 h (567.08 IU L- 1 h- 1). The extracted xylan from SB induced more xylanase in the fermentation medium than pretreated SB or commercially purified xylan. Nuclear Magnetic Resonance, Fourier transform infrared spectroscopy and scanning electron microscopy of SB indicated removal of lignin and changes in the structure of SB after NaOH+IL pretreatment and fermentation. CONCLUSION Combined pretreatment of SB with alkali and methyltrioctylammonium chloride appeared better than other chemical methods for bacterial xylanase production and for the extraction of xylan form SB.
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Affiliation(s)
- Rozina Rashid
- Department of Microbiology, University of Karachi, 75270, Karachi, Pakistan.,Department of Microbiology, University of Balochistan, Quetta, Pakistan
| | - Uroosa Ejaz
- Department of Microbiology, University of Karachi, 75270, Karachi, Pakistan
| | - Firdous Imran Ali
- Department of Chemistry, University of Karachi, 75270, Karachi, Pakistan
| | - Imran Ali Hashmi
- Department of Chemistry, University of Karachi, 75270, Karachi, Pakistan
| | - Ahmed Bari
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Jing Liu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570228, China
| | - Li Wang
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570228, China
| | - Pengcheng Fu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570228, China.
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, 75270, Karachi, Pakistan.
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18
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Khan MT, Ejaz U, Sohail M. Evaluation of Factors Affecting Saccharification of Sugarcane Bagasse Using Cellulase Preparation from a Thermophilic Strain of Brevibacillus sp. Curr Microbiol 2020; 77:2422-2429. [PMID: 32488408 DOI: 10.1007/s00284-020-02059-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/26/2020] [Indexed: 11/25/2022]
Abstract
This study focuses on the production of cellulase from a thermophilic bacterium Brevibacillus sp. MT5 and prospects of utilizing the enzyme preparation for the saccharification of sugarcane bagasse (SB). The data revealed that cellulase produced at 70 °C expressed an IFPU (international filter paper unit) of 1.776 when assayed at 60 °C and showed good activity towards SB. Consequently, the conditions affecting saccharification of SB were studied by employing a Plackett-Burman design and reducing sugars were determined by dinitrosalicylic acid method and glucose oxidase kit. The analysis of the design highlighted that the factors affecting the hydrolysis process varies in terms of their significance with respect to the duration of the reaction, however, agitation remained a consistent significant factor throughout the process. Gravimetric analysis displayed a reduction of 49.7 and 22.6% in cellulose content after saccharification of SB from an industry and SB from a fruit juice vendor, respectively. The effect of enzyme action on SB was further visualized by scanning electron microscopy and Fourier transform infra-red spectroscopy that showed increased porosity and a diminished peak for cellulose, indicating degradation of the substrate by the enzyme preparation.
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Affiliation(s)
- Maria Tariq Khan
- Department of Microbiology, University of Karachi, Karachi, 75270, Pakistan
| | - Uroosa Ejaz
- Department of Microbiology, University of Karachi, Karachi, 75270, Pakistan
| | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Karachi, 75270, Pakistan.
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19
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Ejaz U, Muhammad S, Hashmi IA, Ali FI, Sohail M. Utilization of methyltrioctylammonium chloride as new ionic liquid in pretreatment of sugarcane bagasse for production of cellulase by novel thermophilic bacteria. J Biotechnol 2020; 317:34-38. [PMID: 32360575 DOI: 10.1016/j.jbiotec.2020.04.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/18/2020] [Accepted: 04/23/2020] [Indexed: 10/24/2022]
Abstract
Fermentation of carbohydrates present in lignocellulosic (LC) biomass is facilitated by lignin removal, which is usually achieved by adopting various pretreatment methods to provide the enzymes proper access to their respective substrates. Pretreatment using ionic liquid (IL) is relatively recent advancement and considered as mild and green process. ILs can dissolve extensive quantities of biomass and depolymerize the cellulose. In this context, an abundantly available LC biomass, sugarcane bagasse (SB), was pretreated using alkali or with an IL, methyltrioctylammonium chloride, and was used for cellulase production from thermophilic bacteria. In all, 26 indigenously isolated thermophilic bacterial strains were quantitatively screened for cellulase production. 16S rDNA sequences of the promising isolates UE10 and UE27 revealed relatedness with Brevibacillus borstelensis, while the strain UE1 belonged to Aneurinibacillus thermoaerophilus. Cellulase production was compared by utilizing alkali pretreated and IL pretreated SB and the later was found more appropriate. UE1, UE10 and UE27 yielded 22.2, 22.18 and 33.3 IU mL-1 of endoglucanase, respectively, by fermenting IL pretreated SB. The changes in SB structure after pretreatment were evaluated by scanning electron microscopy. This study demonstrated the potential of novel thermophilic bacterial strains to utilize IL pretreated SB for production of industrially important enzyme, cellulase.
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Affiliation(s)
- Uroosa Ejaz
- Department of Microbiology, University of Karachi, Pakistan
| | | | | | | | - Muhammad Sohail
- Department of Microbiology, University of Karachi, Pakistan.
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