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Lin Y, Dong Y, Li X, Cai J, Cai L, Zhang G. Enzymatic production of xylooligosaccharide from lignocellulosic and marine biomass: A review of current progress, challenges, and its applications in food sectors. Int J Biol Macromol 2024; 277:134014. [PMID: 39047995 DOI: 10.1016/j.ijbiomac.2024.134014] [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: 09/18/2023] [Revised: 04/03/2024] [Accepted: 07/17/2024] [Indexed: 07/27/2024]
Abstract
Over the last decade, xylooligosaccharides (XOS) have attracted great attentions because of their unique chemical properties and excellent prebiotic effects. Among the current strategies for XOS production, enzymatic hydrolysis is preferred due to its green and safe process, simplicity in equipment, and high control of the degrees of polymerization. This paper comprehensively summarizes various lignocellulosic biomass and marine biomass employed in enzymatic production of XOS. The importance and advantages of enzyme immobilization in XOS production are also discussed. Many novel immobilization techniques for xylanase are presented. In addition, bioinformatics techniques for the mining and designing of new xylanase are also described. Moreover, XOS has exhibited great potential applications in the food industry as diverse roles, such as a sugar replacer, a fat replacer, and cryoprotectant. This review systematically summarizes the current research progress on the applications of XOS in food sectors, including beverages, bakery products, dairy products, meat products, aquatic products, food packaging film, wall materials, and others. It is anticipated that this paper will act as a reference for the further development and application of XOS in food sectors and other fields.
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Affiliation(s)
- Yuanqing Lin
- College of Environment and Public Health, Xiamen Huaxia University, Xiamen 361024, Fujian, China
| | - Yuting Dong
- College of Environment and Public Health, Xiamen Huaxia University, Xiamen 361024, Fujian, China; Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen 361021, Fujian, China
| | - Xiangling Li
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Jinzhong Cai
- College of Environment and Public Health, Xiamen Huaxia University, Xiamen 361024, Fujian, China
| | - Lixi Cai
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen 361021, Fujian, China; College of Basic Medicine, Putian University, Putian 351100, Fujian, China.
| | - Guangya Zhang
- Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen 361021, Fujian, China.
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Rodríguez-Sanz A, Fuciños C, Míguez M, Rúa ML, Torrado AM. Direct enzymatic hydrolysis of solid wheat straw with endo-xylanases: Effect of the temperature on the hemicellulose release and the product profile modulation. Int J Biol Macromol 2024; 270:132211. [PMID: 38723833 DOI: 10.1016/j.ijbiomac.2024.132211] [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] [Received: 11/29/2023] [Revised: 04/28/2024] [Accepted: 05/07/2024] [Indexed: 05/20/2024]
Abstract
Prebiotics are non-digestible compounds that promote intestinal microbiota growth and/or activity. Xylooligosaccharides (XOS) are new prebiotics derived from the hemicellulose fraction of lignocellulosic materials. Challenges in using those materials as sources for prebiotic compounds lie in the hemicellulose extraction efficiency and the safety of those ingredients. In this sense, this work aims to optimize hemicellulose extraction and XOS production through direct enzymatic hydrolysis of alkali pre-treated wheat straw without undesired byproducts. By increasing the temperature of the enzymatic step from 40 °C to 65 °C we achieved an improvement in the extraction yield from 55 % to 80 %. Products with different degrees of polymerization were also noticed: while XOS ≤ X6 where the main products at 40 °C, a mixture of long arabinoxylan derived polymers (ADPo) and XOS ≤ X6 was obtained at 65 °C, irrespective of the extraction yield. Thus, a modulatory effect of temperature on the product profile is suggested here. Among the XOS ≤ X6 produced, X2-X3 were the main products, and X4 was the minor one. At the end of the hydrolysis, 146.7 mg XOS per gram of pre-treated wheat straw were obtained.
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Affiliation(s)
- Andrea Rodríguez-Sanz
- Biochemistry Laboratory, Department of Analytical and Food Chemistry, University of Vigo, Ourense, Spain
| | - Clara Fuciños
- Biochemistry Laboratory, Department of Analytical and Food Chemistry, University of Vigo, Ourense, Spain
| | - Martín Míguez
- Biochemistry Laboratory, Department of Analytical and Food Chemistry, University of Vigo, Ourense, Spain
| | - María L Rúa
- Biochemistry Laboratory, Department of Analytical and Food Chemistry, University of Vigo, Ourense, Spain
| | - Ana M Torrado
- Biochemistry Laboratory, Department of Analytical and Food Chemistry, University of Vigo, Ourense, Spain.
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Zhou H, Cai Y, Long M, Zheng N, Zhang Z, You C, Hussain A, Xia X. Computer-Aided Reconstruction and Application of Bacillus halodurans S7 Xylanase with Heat and Alkali Resistance. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:1213-1227. [PMID: 38183306 DOI: 10.1021/acs.jafc.3c08221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2024]
Abstract
β-1,4-Endoxylanase is the most critical hydrolase for xylan degradation during lignocellulosic biomass utilization. However, its poor stability and activity in hot and alkaline environments hinder its widespread application. In this study, BhS7Xyl from Bacillus halodurans S7 was improved using a computer-aided design through isothermal compressibility (βT) perturbation engineering and by combining three thermostability prediction algorithms (ICPE-TPA). The best variant with remarkable improvement in specific activity, heat resistance (70 °C), and alkaline resistance (both pH 9.0 and 70 °C), R69F/E137M/E145L, exhibited a 4.9-fold increase by wild-type in specific activity (1368.6 U/mg), a 39.4-fold increase in temperature half-life (458.1 min), and a 57.6-fold increase in pH half-life (383.1 min). Furthermore, R69F/E137M/E145L was applied to the hydrolysis of agricultural waste (corncob and hardwood pulp) to efficiently obtain a higher yield of high-value xylooligosaccharides. Overall, the ICPE-TPA strategy has the potential to improve the functional performance of enzymes under extreme conditions for the high-value utilization of lignocellulosic biomass.
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Affiliation(s)
- Huimin Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Yongchao Cai
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Mengfei Long
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Nan Zheng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Zehua Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Cuiping You
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Asif Hussain
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Xiaole Xia
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, Jiangsu, China
- College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin 300000, China
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Valladares-Diestra KK, de Souza Vandenberghe LP, Vieira S, Goyzueta-Mamani LD, de Mattos PBG, Manzoki MC, Soccol VT, Soccol CR. The Potential of Xylooligosaccharides as Prebiotics and Their Sustainable Production from Agro-Industrial by-Products. Foods 2023; 12:2681. [PMID: 37509773 PMCID: PMC10379617 DOI: 10.3390/foods12142681] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
In recent years, concerns about a good-quality diet have increased. Food supplements such as prebiotics have great nutritional and health benefits. Within the diverse range of prebiotics, xylooligosaccharides (XOs) show high potential, presenting exceptional properties for the prevention of systemic disorders. XOs can be found in different natural sources; however, their production is limited. Lignocellulosic biomasses present a high potential as a source of raw material for the production of XOs, making the agro-industrial by-products the perfect candidates for production on an industrial scale. However, these biomasses require the application of physicochemical pretreatments to obtain XOs. Different pretreatment methodologies are discussed in terms of increasing the production of XOs and limiting the coproduction of toxic compounds. The advance in new technologies for XOs production could decrease their real cost (USD 25-50/kg) on an industrial scale and would increase the volume of market transactions in the prebiotic sector (USD 4.5 billion). In this sense, new patents and innovations are being strategically developed to expand the use of XOs as daily prebiotics.
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Affiliation(s)
- Kim Kley Valladares-Diestra
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Luciana Porto de Souza Vandenberghe
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Sabrina Vieira
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Luis Daniel Goyzueta-Mamani
- Vicerrectorado de Investigación, Universidad Católica de Santa María, Urb. San José s/n-Umacollo, Arequipa 04000, Peru
| | - Patricia Beatriz Gruening de Mattos
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Maria Clara Manzoki
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Vanete Thomaz Soccol
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
| | - Carlos Ricardo Soccol
- Department of Bioprocess Engineering and Biotechnology, Centro Politécnico, Federal University of Paraná, Curitiba 81531-980, Paraná, Brazil
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Kovalev AA, Kovalev DA, Zhuravleva EA, Laikova AA, Shekhurdina SV, Vivekanand V, Litti YV. Biochemical hydrogen potential assay for predicting the patterns of the kinetics of semi-continuous dark fermentation. BIORESOURCE TECHNOLOGY 2023; 376:128919. [PMID: 36934902 DOI: 10.1016/j.biortech.2023.128919] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 03/13/2023] [Accepted: 03/15/2023] [Indexed: 06/18/2023]
Abstract
The performance and kinetics response of thermophilic semi-continuous dark fermentation (DF) of simulated complex carbohydrate-rich waste was investigated at various hydraulic retention times (HRT) (2, 2.5, and 3 d) and compared with data obtained from biochemical hydrogen potential assay (BHP). A culture of Thermoanaerobacterium thermosaccharolyticum was used as the inoculum and dominated both in BHP and semi-continuous reactor. Both the modified Gompertz and first-order models described the DF kinetics well (R2 = 0.97-1.00). HRT of 2.5 d was found to be optimal in terms of maximum hydrogen production rate and hydrogen potential, which were 3.97 and 1.26 times higher, respectively, than in BHP. The hydrolysis constant was highest at HRT of 3 d and was closest to the value obtained in the BHP. Overall, BHP has been shown to be a useful tool for predicting H2 potential and the hydrolysis constant, while the maximum H2 production rate is greatly underestimated.
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Affiliation(s)
- Andrey A Kovalev
- Federal Scientific Agroengineering Center VIM, 1st Institutsky Proezd, 5, 109428 Moscow, Russia.
| | - Dmitriy A Kovalev
- Federal Scientific Agroengineering Center VIM, 1st Institutsky Proezd, 5, 109428 Moscow, Russia
| | - Elena A Zhuravleva
- Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, 117312 Moscow, Russia
| | - Alexandra A Laikova
- Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, 117312 Moscow, Russia
| | - Svetlana V Shekhurdina
- Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, 117312 Moscow, Russia
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, Jaipur 302017, Rajasthan, India
| | - Yuriy V Litti
- Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, 60 Let Oktjabrja Pr-t, 7, Bld. 2, 117312 Moscow, Russia
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Kaur P, Khatri M, Singh G, Selvaraj M, Assiri MA, Lalthazuala Rokhum S, Kumar Arya S, Jones S, Greff B, Woong Chang S, Ravindran B, Awasthi MK. Xylopentose production from crop residue employing xylanase enzyme. BIORESOURCE TECHNOLOGY 2023; 370:128572. [PMID: 36603755 DOI: 10.1016/j.biortech.2022.128572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/30/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
To produce xylo-oligosaccharides (XOS) from the agriculture waste, which included, green coconut and vegetable cocktail. The two pretreatment - hydrogen peroxide-acetic acid (HP-AC) and sodium hypochlorite-sodium hydroxide (SH-SH) - were used for this study. The optimal conditions for the pretreatment were 80 °C, 4.0 % NaClO, and 2 h, followed by 0.08 % NaOH, 55 °C, and 1 h. Further enzymatic hydrolysis of green coconut (GC) and vegetable cocktail (VC) were performed and found in case of GC, the best outcomes were observed. Different types of XOS were obtained from the treated biomass whereas a single type of XOS xylo-pentose was obtained in high quantity (96.44 % and 93.09 % from CG and VC respectively) with the production of other XOS < 2 %. This study presents a reasonably secure and economical method for turning secondary crop residue into XOS and fermentable sugars.
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Affiliation(s)
- Pritam Kaur
- College of Natural Resources and Environment, Northwest A&F University, TaichengRoad3# Shaanxi, Yangling 712100, China; Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, India
| | - Madhu Khatri
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, India
| | - Gursharan Singh
- Department of Medical Laboratory Sciences, Lovely Professional University, Phagwara 144411, Punjab, India
| | - Manickam Selvaraj
- Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia
| | - Mohammed A Assiri
- Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia
| | | | - Shailendra Kumar Arya
- Department of Biotechnology, University Institute of Engineering and Technology, Panjab University, Chandigarh, India
| | - Sumathi Jones
- Department of Pharmacology, Sree Balaji Dental College and Hospital, BIHER, Chennai 600100, India
| | - Babett Greff
- Department of Food Science, Albert Casimir Faculty at Mosonmagyaróvár, Széchenyi István University, 15-17 Lucsony Street, 9200 Mosonmagyaróvár, Hungary
| | - Soon Woong Chang
- Department of Environmental Energy and Engineering, Kyonggi University, Yeongtong-Gu, Suwon- Si, Gyeonggi-Do 16227, Republic of Korea
| | - Balasubramani Ravindran
- Department of Environmental Energy and Engineering, Kyonggi University, Yeongtong-Gu, Suwon- Si, Gyeonggi-Do 16227, Republic of Korea; Department of Medical Biotechnology and Integrative Physiology, Institute of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Thandalam, Chennai 602105, Tamil Nadu, India
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, TaichengRoad3# Shaanxi, Yangling 712100, China.
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Mehmet Bektas, Orhan F, Baris O. Isolation of Biological Control Agents and Biotechnological Bacteria from Aquatic Insect Gut Microbiota (Coleoptera: Helophoridae, Hydrophilidae). BIOL BULL+ 2022. [DOI: 10.1134/s1062359022060036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Production of Xylooligosaccharides from Jiuzao by Autohydrolysis Coupled with Enzymatic Hydrolysis Using a Thermostable Xylanase. Foods 2022; 11:foods11172663. [PMID: 36076846 PMCID: PMC9455638 DOI: 10.3390/foods11172663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/23/2022] [Accepted: 08/26/2022] [Indexed: 12/03/2022] Open
Abstract
The production of xylooligosaccharides (XOS) from Jiuzao was studied using a two-stage process based on autohydrolysis pretreatment followed by enzymatic hydrolysis. Jiuzao was autohydrolyzed under conditions where temperature, time, particle size, and solid-liquid ratio were varied experimentally. Optimal XOS production was obtained from Jiuzao with a >20 mesh particle size treated at 181.5 °C for 20 min with a 1:13.6 solid-liquid ratio. Subsequently, optimal enzymatic hydrolysis conditions for xylanase XynAR were identified as 60 °C, pH 5, and xylanase XynAR loading of 15 U/mL. Using these conditions, a yield of 34.2% XOS was obtained from Jiuzao within 2 h. The process developed in the present study could enable effective and ecofriendly industrial production of XOS from Jiuzao.
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Zhang J, Gao S, Zheng F, Wang N. Intestinal Bacterial Diversity and Functional Analysis of Three Lepidopteran Corn Ear Worm Larvae. INSECTS 2022; 13:740. [PMID: 36005365 PMCID: PMC9409944 DOI: 10.3390/insects13080740] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/13/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Insects, as the most abundant animal group on earth, and their symbionts help their hosts to adapt to various environments. Conogethes punctiferalis, Ostrinia furnacalis and Helicoverpa armigera are three main pests co-occurring in the ear stage of corn, which significantly affect the yield and quality of corn. The purpose of this study was to compare the diversity and function of the intestinal bacteria of the three co-occurring lepidopteran pests, C. punctiferalis, O. furnacalis and H. armigera, and to explore the reason of their prevalence from the microbiota's view. Our results showed the difference of diversity and abundance of the gut bacteria of three co-occurring lepidopteran pests at the ear stage. Proteobacteria and Firmicutes were the dominant phyla, and the Enterobacteriaceae and Enterococcaceae were the dominant families in the three pests. Compared with the other two pests, Bacteroidetes was found much more in C. punctiferalis. In addition, C. punctiferalis showed more correlation and similarity in bacteria composition with corn endophytic bacteria, as well as had obvious advantages in metabolic, environmental information processing, cellular processes and organic systems function pathways. Our findings may provide insight into the prevalence of corn earworm larvae from the perspective of gut microbiota and function prediction.
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Mehta D, Purohit A, Bajarh P, Yadav K, Shivhare U, Yadav SK. Cold plasma processing improved the extraction of xylooligosaccharides from dietary fibers of rice and corn bran with enhanced in-vitro digestibility and anti-inflammatory responses. INNOV FOOD SCI EMERG 2022. [DOI: 10.1016/j.ifset.2022.103027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Zhu X, Yellezuome D, Liu R, Wang Z, Liu X. Effects of co-digestion of food waste, corn straw and chicken manure in two-stage anaerobic digestion on trace element bioavailability and microbial community composition. BIORESOURCE TECHNOLOGY 2022; 346:126625. [PMID: 34958901 DOI: 10.1016/j.biortech.2021.126625] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Co-digestion is known to effectively alleviate trace elements (TEs) deficiency in mono-substrates; however, the bioavailability of TEs is crucial for the stability of anaerobic digestion. Therefore, this study investigated the effects of co-digestion of food waste (FW), corn straw (CS) and chicken manure (CM) in two-stage anaerobic digestion on TEs bioavailability and microbial community composition. Various VSFW:(VSCS:VSCM) ratios of 8:2, 7:3, 4:6, and 2:8 were evaluated in two-stage (group A, B, C, D) anaerobic digestion in which the VSCS:VSCM ratio was fixed at 3:1. Results showed that the highest hydrogen production of 106 mL/g VS and methane production co-efficiency of 125.3% was obtained in group A. Group A has a high close range of easily bioavailable TEs (32-64%) compared to other groups, especially the mono-substrate, where almost all TEs ranged between 10 and 36%. The increased relative abundance of the obligate hydrogenotrophic methanogens reflected a positive two-stage methane co-digestion efficiency.
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Affiliation(s)
- Xianpu Zhu
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, 800 Dongchuan Road, Shanghai 200240, PR China
| | - Dominic Yellezuome
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, 800 Dongchuan Road, Shanghai 200240, PR China
| | - Ronghou Liu
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, 800 Dongchuan Road, Shanghai 200240, PR China.
| | - Zengzhen Wang
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, 800 Dongchuan Road, Shanghai 200240, PR China
| | - Xin Liu
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Key Laboratory of Urban Agriculture (South), Ministry of Agriculture and Rural Affairs, 800 Dongchuan Road, Shanghai 200240, PR China
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12
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Min K, Kim H, Park HJ, Lee S, Jung YJ, Yoon JH, Lee JS, Park K, Yoo YJ, Joo JC. Improving the catalytic performance of xylanase from Bacillus circulans through structure-based rational design. BIORESOURCE TECHNOLOGY 2021; 340:125737. [PMID: 34426235 DOI: 10.1016/j.biortech.2021.125737] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
Endo-1,4-β-xylanase is one of the most important enzymes employed in biorefineries for obtaining fermentable sugars from hemicellulosic components. Herein, we aimed to improve the catalytic performance of Bacillus circulans xylanase (Bcx) using a structure-guided rational design. A systematic analysis of flexible motions revealed that the R49 component of Bcx (i) constrains the global conformational changes essential for substrate binding and (ii) is involved in modulating flexible motion. Site-saturated mutagenesis of the R49 residue led to the engineering of the active mutants with the trade-off between flexibility and rigidity. The most active mutant R49N improved the catalytic performance, including its catalytic efficiency (7.51-fold), conformational stability (0.7 °C improvement), and production of xylose oligomers (2.18-fold higher xylobiose and 1.72-fold higher xylotriose). The results discussed herein can be applied to enhance the catalytic performance of industrially important enzymes by controlling flexibility.
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Affiliation(s)
- Kyoungseon Min
- Gwangju Bio/Energy R&D Center, Korea Institute of Energy Research (KIER), Gwangju 61003, Republic of Korea
| | - Hoyong Kim
- Center for Bio-Based Chemistry, Korea Research Institute of Chemical Technology, Ulsan 44429, Republic of Korea
| | - Hyun June Park
- Department of Biotechnology, Duksung Women's University, Seoul 01369, Republic of Korea
| | - Siseon Lee
- Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Ye Jean Jung
- Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea; Department of Biological and Chemical Engineering, Hongik University, Sejong Ro 2639, Jochiwon, Sejong City, Republic of Korea
| | - Ji Hyun Yoon
- Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea
| | - Jin-Suk Lee
- Gwangju Bio/Energy R&D Center, Korea Institute of Energy Research (KIER), Gwangju 61003, Republic of Korea
| | - Kyoungmoon Park
- Department of Biological and Chemical Engineering, Hongik University, Sejong Ro 2639, Jochiwon, Sejong City, Republic of Korea
| | - Young Je Yoo
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Jeong Chan Joo
- Center for Bio-Based Chemistry, Korea Research Institute of Chemical Technology, Ulsan 44429, Republic of Korea; Department of Biotechnology, The Catholic University of Korea, Bucheon-si, Gyeonggi-do 14662, Republic of Korea.
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Purohit A, Singh G, Yadav SK. Chimeric bi-functional enzyme possessing xylanase and deacetylase activity for hydrolysis of agro-biomass rich in acetylated xylan. Colloids Surf B Biointerfaces 2021; 204:111832. [PMID: 33984614 DOI: 10.1016/j.colsurfb.2021.111832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/04/2021] [Accepted: 05/07/2021] [Indexed: 10/21/2022]
Abstract
Here, a chimeric bifunctional enzyme was developed for two activities xylanase and deacetylase. Chimeric enzyme was designed by combining the relevant amino acid stretches from two different parent sequences, such as polysaccharide/xylan deacetylase (ref id: MT682066) and xylanase (ref id WP_110897546.1). Five different hypothetical chimeras were developed and one of the best predicted chimeric protein GA_2(syn_SKYAP01) was synthesized. The GA_2(syn_SKYAP01) possessed the specific activity of 14.905 ± 0.8 U/mg for deacetylase and 100.87 ± 14.2 U/mg for xylanase. Optimum level of both the activities together was achieved at pH 5 and 60 °C. The chimeric protein was also found to be stable at higher temperature of 71°C. Functionality of the developed chimeric protein for both the activities was confirmed by the hydrolysis of commercial xylan into xylooligosaccharides and the release of acetic acid from glucose pentacetate and 7-amino cephalosporin. The designed bifunctional enzyme was found to be highly efficient.
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Affiliation(s)
- Anjali Purohit
- Center of Innovative and Applied Bioprocessing (CIAB), Sector-81 (Knowledge City), Mohali, 140306, PB, India
| | - Gurjant Singh
- Center of Innovative and Applied Bioprocessing (CIAB), Sector-81 (Knowledge City), Mohali, 140306, PB, India
| | - Sudesh Kumar Yadav
- Center of Innovative and Applied Bioprocessing (CIAB), Sector-81 (Knowledge City), Mohali, 140306, PB, India.
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Patel A, Shah AR. Integrated lignocellulosic biorefinery: Gateway for production of second generation ethanol and value added products. JOURNAL OF BIORESOURCES AND BIOPRODUCTS 2021. [DOI: 10.1016/j.jobab.2021.02.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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15
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Rai SK, Kumar V, Yadav SK. Development of recyclable magnetic cross-linked enzyme aggregates for the synthesis of high value rare sugar d-tagatose in aqueous phase catalysis. Catal Sci Technol 2021. [DOI: 10.1039/d0cy02397c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In this study, a high value rare sugar d-tagatose was synthesized using recyclable magnetic catalysts.
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Affiliation(s)
- Shushil Kumar Rai
- Center of Innovative and Applied Bioprocessing (CIAB)
- Mohali 140306
- India
- Dept. of Microbial Biotechnology
- Panjab University
| | - Varun Kumar
- Center of Innovative and Applied Bioprocessing (CIAB)
- Mohali 140306
- India
| | - Sudesh Kumar Yadav
- Center of Innovative and Applied Bioprocessing (CIAB)
- Mohali 140306
- India
- Dept. of Microbial Biotechnology
- Panjab University
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16
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Mugnai G, Borruso L, Mimmo T, Cesco S, Luongo V, Frunzo L, Fabbricino M, Pirozzi F, Cappitelli F, Villa F. Dynamics of bacterial communities and substrate conversion during olive-mill waste dark fermentation: Prediction of the metabolic routes for hydrogen production. BIORESOURCE TECHNOLOGY 2021; 319:124157. [PMID: 32987280 DOI: 10.1016/j.biortech.2020.124157] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 06/11/2023]
Abstract
The aim of this work was to study the biological catalysts and possible substrate conversion routes in mesophilic dark fermentation reactors aimed at producing H2 from olive mill wastewater. Bacillus and Clostridium were the most abundant phylotypes during the rapid stage of H2 production. Chemical analyses combined with predictive functional profiling of the bacterial communities indicated that the lactate fermentation was the main H2-producing route. In fact, during the fermentation process, lactate and acetate were consumed, while H2 and butyrate were being produced. The fermentation process was rich in genes that encode enzymes for lactate generation from pyruvate. Lactate conversion to butyrate through the generation of pyruvate produced H2 through the recycling of electron carriers via the pyruvate ferredoxin oxydoreductase pathway. Overall, these findings showed the synergy among lactate-, acetate- and H2-producing bacteria, which complex interactions determine the H2 production routes in the bioreactors.
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Affiliation(s)
- Gianmarco Mugnai
- Department of Food, Environmental and Nutritional Sciences, University of Milan, via Celoria 2, 20133 Milan, Italy
| | - Luigimaria Borruso
- Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Tanja Mimmo
- Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Stefano Cesco
- Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Vincenzo Luongo
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples "Federico II", via Cintia, Monte S. Angelo, 80126 Naples, Italy
| | - Luigi Frunzo
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples "Federico II", via Cintia, Monte S. Angelo, 80126 Naples, Italy
| | - Massimiliano Fabbricino
- Department of Civil, Architectural and Environmental Engineering, University of Naples "Federico II", via Claudio 21, 80125 Naples, Italy
| | - Francesco Pirozzi
- Department of Civil, Architectural and Environmental Engineering, University of Naples "Federico II", via Claudio 21, 80125 Naples, Italy
| | - Francesca Cappitelli
- Department of Food, Environmental and Nutritional Sciences, University of Milan, via Celoria 2, 20133 Milan, Italy
| | - Federica Villa
- Department of Food, Environmental and Nutritional Sciences, University of Milan, via Celoria 2, 20133 Milan, Italy.
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Characterization of a thermotolerant and acidophilic mannanase producing Microbacterium sp. CIAB417 for mannooligosachharide production from agro-residues and dye decolorization. Int J Biol Macromol 2020; 163:1154-1161. [PMID: 32673718 DOI: 10.1016/j.ijbiomac.2020.07.114] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/10/2020] [Accepted: 07/10/2020] [Indexed: 11/20/2022]
Abstract
Mannanases are ubiquitous enzymes and are being explored for diverse industrial applications. In this study, a novel bacterial strain Microbacterium sp. CIAB417 was identified and characterized for extracellular production of mannanase. Microbacterium sp. CIAB417 was found to produce maximum mannanase after 36 h of incubation at 37 °C. Mannanase produced by the isolate was observed for maximum activity at optimum pH of 6 and optimum temperature of 50 °C. Crude mannanase was found to be capable of producing mannooligosachharides (MOS) by hydrolyzing hemicellulose from locust bean gum and Aloe vera. The produced MOS was characterized and found to be mixture of mannobiose to mannohexose units. Mannanase was also explored for decolorization of dyes. Bromophenol blue and coomassie blue R-250 were observed to be decolorized to the extent of 45.40 and 42.75%, respectively. Hence, the identified bacterial strain producing mannanase could be of great significance for applications in food and textile industry.
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18
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Acosta-Fernández R, Poerio T, Nabarlatz D, Giorno L, Mazzei R. Enzymatic Hydrolysis of Xylan from Coffee Parchment in Membrane Bioreactors. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.9b06429] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Rolando Acosta-Fernández
- INTERFASE, Chemical Engineering School, Universidad Industrial de Santander, Cra 27 No. 9, 680002Bucaramanga, Colombia
| | - Teresa Poerio
- Institute on Membrane Technology, National Research Council, ITM-CNR, Via P. Bucci 17/C at University of Calabria, 87036 Rende CS, Italy
| | - Debora Nabarlatz
- INTERFASE, Chemical Engineering School, Universidad Industrial de Santander, Cra 27 No. 9, 680002Bucaramanga, Colombia
| | - Lidietta Giorno
- Institute on Membrane Technology, National Research Council, ITM-CNR, Via P. Bucci 17/C at University of Calabria, 87036 Rende CS, Italy
| | - Rosalinda Mazzei
- Institute on Membrane Technology, National Research Council, ITM-CNR, Via P. Bucci 17/C at University of Calabria, 87036 Rende CS, Italy
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19
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Gupta MN, Perwez M, Sardar M. Protein crosslinking: Uses in chemistry, biology and biotechnology. BIOCATAL BIOTRANSFOR 2020. [DOI: 10.1080/10242422.2020.1733990] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
| | - Mohammad Perwez
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Meryam Sardar
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
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20
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Bioprospecting potential of microbial communities in solid waste landfills for novel enzymes through metagenomic approach. World J Microbiol Biotechnol 2020; 36:34. [PMID: 32088773 DOI: 10.1007/s11274-020-02812-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 02/13/2020] [Indexed: 01/19/2023]
Abstract
Landfills are repository for complex microbial diversity responsible for bio-degradation of solid waste. To elucidate this complexity, samples from three different landfill sites of North India (sample V: Bhalswa near Karnal byepass road, New Delhi, India; sample T: Chandigarh, India and sample S3: Una, H.P., India) were analyzed using metagenomic approach. Selected landfill sites had different geographical location, varied in waste composition, size of landfill and climate zone. For comparison, one sample from high altitude (sample J) having less human interference was taken in this study. The aim of this study was to explore microbial diversity of communities responsible for degradation of landfill. Samples were characterized by 16S rRNA gene sequencing. Data from three landfill sites showed abundance of phylum Proteobacteria while less contaminated sample from high altitude showed abundance of phylum Cholroflexi followed by phylum Proteobacteria. The most abundant genus was unknown suggesting that these landfills could be repository for various novel bacterial communities. Sample T was relatively more active in terms of microbial activity. It was relatively abundant in enzymes responsible for dioxin degradation, styrene degradation, steroid degradation, streptomycin biosynthesis, carbapenem biosynthesis, monobactam biosynthesis, furfural degradation pathways while sample J was predicted to be enriched in plant cell wall degrading enzymes. Co-occurrence analysis revealed presence of complex interaction networks between microbial assemblages responsible for bio-degradation of hydrocarbons. The data provides insights about synergetic interactions and functional interplay between bacterial communities in different landfill sites which could be further exploited to develop an effective bioremediation process.
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Amorim C, Silvério SC, Prather KL, Rodrigues LR. From lignocellulosic residues to market: Production and commercial potential of xylooligosaccharides. Biotechnol Adv 2019; 37:107397. [DOI: 10.1016/j.biotechadv.2019.05.003] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/07/2019] [Accepted: 05/04/2019] [Indexed: 12/25/2022]
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22
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Abdul Wahab MKH, El-Enshasy HA, Bakar FDA, Murad AMA, Jahim JM, Illias RM. Improvement of cross-linking and stability on cross-linked enzyme aggregate (CLEA)-xylanase by protein surface engineering. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.07.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Kumar S, Dangi AK, Shukla P, Baishya D, Khare SK. Thermozymes: Adaptive strategies and tools for their biotechnological applications. BIORESOURCE TECHNOLOGY 2019; 278:372-382. [PMID: 30709766 DOI: 10.1016/j.biortech.2019.01.088] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 05/10/2023]
Abstract
In today's scenario of global climate change, there is a colossal demand for sustainable industrial processes and enzymes from thermophiles. Plausibly, thermozymes are an important toolkit, as they are known to be polyextremophilic in nature. Small genome size and diverse molecular conformational modifications have been implicated in devising adaptive strategies. Besides, the utilization of chemical technology and gene editing attributions according to mechanical necessities are the additional key factor for efficacious bioprocess development. Microbial thermozymes have been extensively used in waste management, biofuel, food, paper, detergent, medicinal and pharmaceutical industries. To understand the strength of enzymes at higher temperatures different models utilize X-ray structures of thermostable proteins, machine learning calculations, neural networks, but unified adaptive measures are yet to be totally comprehended. The present review provides a recent updates on thermozymes and various interdisciplinary applications including the aspects of thermophiles bioengineering utilizing synthetic biology and gene editing tools.
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Affiliation(s)
- Sumit Kumar
- Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Arun K Dangi
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, India
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, India
| | - Debabrat Baishya
- Department of Bioengineering and Technology, Institute of Science and Technology, Gauhati University, Guwahati 781014, Assam, India
| | - Sunil K Khare
- Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110016, India.
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Shahryari Z, Fazaelipoor MH, Ghasemi Y, Lennartsson PR, Taherzadeh MJ. Amylase and Xylanase from Edible Fungus Neurospora intermedia: Production and Characterization. Molecules 2019; 24:molecules24040721. [PMID: 30781572 PMCID: PMC6412995 DOI: 10.3390/molecules24040721] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 02/13/2019] [Accepted: 02/16/2019] [Indexed: 11/16/2022] Open
Abstract
Integrated enzyme production in the biorefinery can significantly reduce the cost of the entire process. The purpose of the present study is to evaluate the production of two hydrolyzing enzymes (amylase and xylanase) by an edible fungus used in the biorefinery, Neurospora intermedia. The enzyme production was explored through submerged fermentation of synthetic media and a wheat-based waste stream (thin stillage and wheat bran). The influence of a nitrogen source on N. intermedia was investigated and a combination of NaNO3 and yeast extract has been identified as the best nitrogen source for extracellular enzyme production. N. intermedia enzymes showed maximum activity at 65 °C and pH around 5. Under these conditions, the maximum velocity of amylase and xylanase for starch and xylan hydrolysis was found to be 3.25 U mL−1 and 14.77 U mL−1, respectively. Cultivation of N. intermedia in thin stillage and wheat bran medium resulted in relatively high amylase (8.86 ± 0.41 U mL−1, 4.68 ± 0.23) and xylanase (5.48 ± 0.21, 2.58 ± 0.07 U mL−1) production, respectively, which makes this fungus promising for enzyme production through a wheat-based biorefinery.
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Affiliation(s)
- Zohre Shahryari
- Swedish Centre for Resource Recovery, University of Borås, SE-50190 Borås, Sweden.
- Department of Chemical Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman, Kerman 7618868366, Iran.
| | - Mohammad H Fazaelipoor
- Department of Chemical Engineering, Faculty of Engineering, Shahid Bahonar University of Kerman, Kerman 7618868366, Iran.
- Department of Chemical and Polymer Engineering, Faculty of Engineering, Yazd University, Yazd 8915818411, Iran.
| | - Younes Ghasemi
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz 71345, Iran.
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz 7146864685, Iran.
| | - Patrik R Lennartsson
- Swedish Centre for Resource Recovery, University of Borås, SE-50190 Borås, Sweden.
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Thermostable Xylanase Production by Geobacillus sp. Strain DUSELR13, and Its Application in Ethanol Production with Lignocellulosic Biomass. Microorganisms 2018; 6:microorganisms6030093. [PMID: 30189618 PMCID: PMC6164562 DOI: 10.3390/microorganisms6030093] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/29/2018] [Accepted: 08/31/2018] [Indexed: 01/11/2023] Open
Abstract
The aim of the current study was to optimize the production of xylanase, and its application for ethanol production using the lignocellulosic biomass. A highly thermostable crude xylanase was obtained from the Geobacillus sp. strain DUSELR13 isolated from the deep biosphere of Homestake gold mine, Lead, SD. Geobacillus sp. strain DUSELR13 produced 6 U/mL of the xylanase with the beechwood xylan. The xylanase production was improved following the optimization studies, with one factor at a time approach, from 6 U/mL to 19.8 U/mL with xylan. The statistical optimization with response surface methodology further increased the production to 31 U/mL. The characterization studies revealed that the crude xylanase complex had an optimum pH of 7.0, with a broad pH range of 5.0⁻9.0, and an optimum temperature of 75 °C. The ~45 kDa xylanase protein was highly thermostable with t1/2 of 48, 38, and 13 days at 50, 60, and 70 °C, respectively. The xylanase activity increased with the addition of Cu+2, Zn+2, K+, and Fe+2 at 1 mM concentration, and Ca+2, Zn+2, Mg+2, and Na⁺ at 10 mM concentration. The comparative analysis of the crude xylanase against its commercial counterpart Novozymes Cellic HTec and Dupont, Accellerase XY, showed that it performed better at higher temperature, hydrolyzing 65.4% of the beechwood at 75 °C. The DUSEL R13 showed the mettle to hydrolyze, and utilize the pretreated, and untreated lignocellulosic biomass: prairie cord grass (PCG), and corn stover (CS) as the substrate, and gave a maximum yield of 20.5 U/mL with the untreated PCG. When grown in co-culture with Geobacillus thermoglucosidasius, it produced 3.53 and 3.72 g/L ethanol, respectively with PCG, and CS. With these characteristics the xylanase under study could be an industrial success for the high temperature bioprocesses.
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