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Wang Y, Gao M, Zhu S, Li Z, Zhang T, Jiang Y, Zhu L, Zhan X. Glycerol-driven adaptive evolution for the production of low-molecular-weight Welan gum: Characterization and activity evaluation. Carbohydr Polym 2024; 339:122292. [PMID: 38823937 DOI: 10.1016/j.carbpol.2024.122292] [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: 03/24/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 06/03/2024]
Abstract
Through adaptive laboratory evolution (ALE) of Sphingomonas sp. ATCC 31555, fermentation for production of low-molecular-weight welan gum (LMW-WG) was performed using glycerol as sole carbon source. During ALE, GPC-MALS analysis revealed a gradual decrease in WG molecular weight with the increase of adaptation cycles, accompanied by changes in solution conformation. LMW-WG was purified and structurally analyzed using GPC-MALS, monosaccharide composition analysis, infrared spectroscopy, NMR analysis, atomic force microscopy, and scanning electron microscopy. Subsequently, LMW-WG obtains hydration, transparency, antioxidant activity, and rheological properties. Finally, an in vitro simulation colon reactor was used to evaluate potential prebiotic properties of LMW-WG as dietary fiber. Compared with WG produced using sucrose as substrate, LMW-WG exhibited a fourfold reduction in molecular weight while maintaining moderate viscosity. Structurally, L-Rha nearly completely replaced L-Man. Furthermore, LMW-WG demonstrated excellent hydration, antioxidant activity, and high transparency. It also exhibited resistance to saliva and gastrointestinal digestion, showcasing a favorable colonization effect on Bifidobacterium, making it a promising symbiotic agent.
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Affiliation(s)
- Yuying Wang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Minjie Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Shengyong Zhu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhitao Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Tiantian Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yun Jiang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Li Zhu
- A & F Biotech. Ltd., Burnaby, BC V5A3P6, Canada
| | - Xiaobei Zhan
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
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2
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Li H, Yue L, Ma S, Lu W, Liu J, Qin L, Wang D, Chang A, Yu B, Kong J, Wang J, Zhu H. The effects of different impeller combinations in the Sphingan WL gum fermentation process. Int J Biol Macromol 2024; 269:132059. [PMID: 38710250 DOI: 10.1016/j.ijbiomac.2024.132059] [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: 11/19/2023] [Revised: 04/28/2024] [Accepted: 05/01/2024] [Indexed: 05/08/2024]
Abstract
The fermentation of the high-viscosity polysaccharide WL gum has always been associated with poor mass transfer. Appropriate impeller configurations are key factors in maintaining homogeneity and sufficient mass transfer conditions. Therefore, a flat-folded disc turbine impeller (FFDT) taking into account both the reduced cavitation effect and the increased contact area was designed. Besides, a curved cross impeller (CC) and a fishbone-shaped impeller (FS) generating axial flow were also designed. The energy consumption and efficiency of the designed impellers and eight reported impellers were evaluated through fermentation and principal component analysis (PCA). Compared to the commonly-used six-blade flat-blade disc turbine (FBDT), the ungassed power number of FFDT was reduced by 50 %. Combinations of six-blade Brumajin impeller (BM) + FFDT and CC + FFDT produced high WL gum production and viscosity (34.0 g/L, 35.50 g/L, and 62.64 Pa·s, 61.68 Pa·s, respectively) and were suitable impellers for WL biosynthesis. WL gum from BM + FFDT showed higher viscosity, viscoelasticity, and molecular weight than that from FBDT + FBDT. In addition, fewer amino acids and pyruvic acid intermediates were formed using BM + FFDT, indicating a greater metabolic flux towards WL gum synthesis. This work provided an important reference for the design of impellers in high-viscosity fermentation systems.
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Affiliation(s)
- Hui Li
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Lin Yue
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Shaohua Ma
- Petroleum Industry Training Center, China University of Petroleum (East China), Qingdao, Shandong 266580, People's Republic of China
| | - Wei Lu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Jianlin Liu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Lijian Qin
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Dong Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Aiping Chang
- Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, Fujian, People's Republic of China
| | - Biyu Yu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Junjie Kong
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Jiqian Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China.
| | - Hu Zhu
- Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, Fujian, People's Republic of China; Key Laboratory of Translational Tumor Medicine in Fujian Province, Putian University, Putian 351100, People's Republic of China.
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3
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Yu C, Zhu H, Fang Y, Qiu Y, Lei P, Xu H, Zhang Q, Li S. Efficient conversion of cane molasses into Tremella fuciformis polysaccharides with enhanced bioactivity through repeated batch culture. Int J Biol Macromol 2024; 264:130536. [PMID: 38432273 DOI: 10.1016/j.ijbiomac.2024.130536] [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: 11/03/2023] [Revised: 02/20/2024] [Accepted: 02/27/2024] [Indexed: 03/05/2024]
Abstract
Tremella fuciformis polysaccharide (TFPS) is a natural mushroom mucopolysaccharide widely used in health foods, medical care, cosmetic and surgical materials. In this study, we developed an efficient strategy for the repeated batch production of highly bioactive TFPS from the agro-industrial residue cane molasses. Cane molasses contained 39.92 % sucrose (w/w), 6.36 % fructose and 3.53 % glucose, all of which could be utilized by T. fuciformis spores, whereas, the TFPS production efficiency only reached 0.74 g/L/d. Corn cobs proved to be the best immobilized carrier that could tightly absorb spores and significantly shorten the fermentation lag period. The average yield of TFPS in eight repeated batch culture was 5.52 g/L with a production efficiency of 2.04 g/L/d. The average fermentation cycle after optimization was reduced by 61.61 % compared with the initial conditions. Compared to glucose as a carbon source, cane molasses significantly increased the proportion of low-molecular-weight TFPS (TFPS-2) in total polysaccharides from 3.54 % to 17.25 % (w/w). Moreover, TFPS-2 exhibited potent antioxidant capacity against four free radicals (O2-, ABTS+, OH, and DPPH). In conclusion, this study lays the foundation for the efficient conversion of cane molasses and production of TFPS with high bioactivity.
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Affiliation(s)
- Caiyuan Yu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Haipeng Zhu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Yan Fang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Yibin Qiu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Peng Lei
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Hong Xu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Qi Zhang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
| | - Sha Li
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
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Cai Z, Guo Y, Ma A, Zhang H. NMR analysis of the side-group substituents in welan gum in comparison to gellan gum. Int J Biol Macromol 2024; 254:127847. [PMID: 37924910 DOI: 10.1016/j.ijbiomac.2023.127847] [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: 04/12/2023] [Revised: 10/02/2023] [Accepted: 10/31/2023] [Indexed: 11/06/2023]
Abstract
The physicochemical properties and applications of polysaccharides are highly dependent on their chemical structures, including the monosaccharide composition, degree of substitution, and position of substituent groups in the backbone. The occurrence of side groups or side chains in the chain backbone of polysaccharides is often an essential factor influencing their conformational and physicochemical properties. Welan gum produced by the fermentation of Sphingomonas sp. ATCC 31555 microorganisms has been widely used in food, construction, and oil drilling fields. While understanding the physicochemical properties of welan gum solution has been highly developed, there is still little information about the determination strategy of the glycosyl side groups in welan gum. In this study, the NMR method was established to quantitatively determine the substituent groups in the chain backbone of welan gum. The delicate chemical structures of welan gum obtained at different fermentation conditions were clarified. The composition and content of side substituents were also identified by high-performance liquid chromatography to confirm the accuracy of NMR analysis. The quantitative determination of substituent groups in gellan gum based on NMR analysis was also elaborated for comparison. This work provides insights for profoundly understanding the structure-function relationship of welan gum.
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Affiliation(s)
- Zhixiang Cai
- Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yalong Guo
- Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Aiqin Ma
- Department of Nutrition, Affiliated Sixth People's Hospital South Campus, Shanghai Jiao Tong University, Shanghai 201499, China.
| | - Hongbin Zhang
- Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, China.
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5
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Liu J, Li H, Zhang X, Yue L, Lu W, Ma S, Zhu Z, Wang D, Zhu H, Wang J. Cost-Efficient Production of the Sphingan WL Gum by Sphingomonas sp. WG Using Molasses and Sucrose as the Carbon Sources. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2023; 25:192-203. [PMID: 36635576 DOI: 10.1007/s10126-022-10193-1] [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: 09/08/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
The polysaccharide WL gum is produced by the marine microorganism Sphingomonas sp. WG and presents great commercial utility potential in many industries especially in oil industries. However, the high fermentation cost limits its wide application. Therefore, an efficient production system at a lower cost was established using beet molasses to partially replace the commonly used carbon sources. Four different molasses were screened and their composition was investigated. One-factor design and RSM statistical analysis were employed to optimize the WL gum fermentation medium. The effects of molasses on the rheological properties and gene expression of WL gum were also investigated. The results showed that the pretreated beet molasses generated both high broth viscosity and WL gum production (12.94 Pa·s and 11.16 g/L). Heavy metal ions and ash were found to be the key factors in unpretreated and pretreated molasses affecting WL production. The cost-efficient production medium contained (g/L): sucrose 61.79, molasses 9.95, yeast extract 1.23, K2HPO4 1, MgSO4 0.1, ZnSO4 0.1 and the WL gum production reached 40.25 ± 1.15 g/L. The WL gum product WL-molasses showed the higher apparent viscosity, and viscous modulus and elastic modulus than WL-sucrose and WL-mix, which might be related to its highest molecular mass. The higher expressional level of genes such as pgm, ugp, ugd, rmlA, welS, and welG in WL gum synthesis in the mixed carbon source medium caused the high production and broth viscosity. This work provided a cost-efficient method for WL gum production.
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Affiliation(s)
- Jianlin Liu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Hui Li
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Xuanyu Zhang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Lin Yue
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Wei Lu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Shaohua Ma
- Petroleum Industry Training Center, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Ziyu Zhu
- School of Resources and Environment, University of Jinan, Jinan, 250022, People's Republic of China
| | - Dong Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China
| | - Hu Zhu
- College of Chemistry and Materials Science, Fujian-Taiwan Science and Technology Cooperation Base of Biomedical Materials and Tissue Engineering, Engineering Research Center of Industrial Biocatalysis, Fujian Normal University, Fuzhou, Fujian, People's Republic of China.
- College of Chemical Engineering and Materials Science, Quanzhou Normal University, Quanzhou, 362000, People's Republic of China.
| | - Jiqian Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, Shandong, People's Republic of China.
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Preparation of Hydrolyzed Sugarcane Molasses as a Low-Cost Medium for the Mass Production of Probiotic Lactobacillus paracasei ssp. paracasei F19. SEPARATIONS 2023. [DOI: 10.3390/separations10010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In this study, sugarcane molasses (SCM) was pre-treated in a low-cost fermentation medium to produce probiotic biomass of Lactobacillus paracasei ssp. paracasei F19 (LPPF19) with the combination of dilution, centrifugation, and acid hydrolysis (5 molar sulfuric acid, 60 °C/2 h). Microtox analysis, inductively coupled mass spectrometry (ICP-MS), and high-performance liquid chromatography (HPLC) were used to measure the effects of SCM pretreatment on the fermentation process. The results showed that the hydrolysis of sucrose into glucose and fructose was 98%, which represented an increase of 44.4% in the initial glucose content (fermentation-limiting sugar), and harmful heavy metals, such as arsenic, cadmium, and lead, were reduced by 50.3, 60.0, and 64.3%, respectively. After pretreatment, with the supplementation of only yeast extract and salts (Na, K, Mg, and Mn), a biomass of 9.58 log CFU/mL was achieved, approximately ten times higher than that for the control medium used (MRS/DeMan, Rogosa, and Sharpe). The cost reduction achieved compared to this commercial medium was 68.7% in the laboratory and 78.9% on an industrial scale. This work demonstrated that SCM could be used in a cheaper and more effective alternative fermentation to produce LPPF19.
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7
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Sustainable Exopolysaccharide Production by Rhizobium viscosum CECT908 Using Corn Steep Liquor and Sugarcane Molasses as Sole Substrates. Polymers (Basel) 2022; 15:polym15010020. [PMID: 36616373 PMCID: PMC9823382 DOI: 10.3390/polym15010020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 12/24/2022] Open
Abstract
Microbial exopolysaccharides (EPS) are promising alternatives to synthetic polymers in a variety of applications. Their high production costs, however, limit their use despite their outstanding properties. The use of low-cost substrates such as agro-industrial wastes in their production, can help to boost their market competitiveness. In this work, an alternative low-cost culture medium (CSLM) was developed for EPS production by Rhizobium viscosum CECT908, containing sugarcane molasses (60 g/L) and corn steep liquor (10 mL/L) as sole ingredients. This medium allowed the production of 6.1 ± 0.2 g EPS/L, twice the amount produced in the standard medium (Syn), whose main ingredients were glucose and yeast extract. This is the first report of EPS production by R. viscosum using agro-industrial residues as sole substrates. EPSCSLM and EPSSyn exhibited a similar carbohydrate composition, mainly 4-linked galactose, glucose and mannuronic acid. Although both EPS showed a good fit to the Herschel-Bulkley model, EPSCSLM displayed a higher yield stress and flow consistency index when compared with EPSSyn, due to its higher apparent viscosity. EPSCSLM demonstrated its potential use in Microbial Enhanced Oil Recovery by enabling the recovery of nearly 50% of the trapped oil in sand-pack column experiments using a heavy crude oil.
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Rahman SSA, Pasupathi S, Karuppiah S. Conventional optimization and characterization of microbial dextran using treated sugarcane molasses. Int J Biol Macromol 2022; 220:775-787. [PMID: 35987362 DOI: 10.1016/j.ijbiomac.2022.08.094] [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: 07/08/2022] [Revised: 08/12/2022] [Accepted: 08/12/2022] [Indexed: 11/30/2022]
Abstract
This study focuses the comparison on yield of microbial dextran using treated sugarcane molasses (SCM) as a feed stock from different treatment methods. The suitable method for treatment of SCM was identified on the basis of microbial dextran production. The different factors namely the concentrations of total sugars, nitrogen sources, inoculum size, shaking speed, initial medium pH, and phosphate sources influencing the production of microbial dextran were studied. The maximum yield of dextran was obtained to be 17.18 ± 0.08 g L-1 using the conventional optimization. The structural analysis of produced dextran from SCM with various treatment techniques was compared using Fourier-transform infra-red analysis and nuclear magnetic resonance spectroscopy. Later, the rheological behavior of produced microbial dextran was examined and found to be a non-Newtonian. To the best of our knowledge, the comparison on the production of microbial dextran through fermentation using SCM with various treatment strategies has not been performed yet.
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Affiliation(s)
- Sameeha Syed Abdul Rahman
- Bioprocess Engineering Laboratory, Centre for Bioenergy, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, 613401, Tamil Nadu, India
| | - Saroja Pasupathi
- Bioprocess Engineering Laboratory, Centre for Bioenergy, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, 613401, Tamil Nadu, India
| | - Sugumaran Karuppiah
- Bioprocess Engineering Laboratory, Centre for Bioenergy, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, 613401, Tamil Nadu, India.
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Zhao M, Hu Y, Yao H, Huang J, Li S, Xu H. Sustainable production and characterization of medium-molecular weight welan gum produced by a Sphingomonas sp. RW. Carbohydr Polym 2022; 289:119431. [DOI: 10.1016/j.carbpol.2022.119431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/10/2022] [Accepted: 03/28/2022] [Indexed: 11/02/2022]
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Ma L, Guo X, Yang J, Zeng X, Ma K, Wang L, Sun Q, Wang Z. Characterization and Antibacterial Activity of a Polysaccharide Produced From Sugarcane Molasses by Chaetomium globosum CGMCC 6882. Front Nutr 2022; 9:935632. [PMID: 35799584 PMCID: PMC9254729 DOI: 10.3389/fnut.2022.935632] [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: 05/04/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
As a by-product of the sugar industry containing many sugars, proteins, nitrogenous materials, and heavy metals, molasses is rarely used for polysaccharide production. In the present work, a Chaetomium globosum CGMCC 6882 polysaccharide was produced from sugarcane molasses (CGP-SM) was successfully produced from sugarcane molasses. The yield of CGP-SM was 5.83 ± 0.09 g/l and its protein content was 2.41 ± 0.12% (w/w). Structural analysis showed that CGP-SM was a crystalline and amorphous polysaccharide containing rhamnose, glucosamine, galactose, glucose, mannose, fructose, and glucuronic acid in the molar ratio of 10.31: 1.14: 2.07: 59.55: 42.65: 1.92: 9.63. Meanwhile, weight-average molecular weight (Mw), number-average molecular weight (Mn), and polydispersity (Mw/Mn) of CGP-SM were 28.37 KDa, 23.66 KDa, and 1.199, respectively. Furthermore, the bacteriostatic assay indicated that CGP-SM inhibited the growth of Escherichia coli and Staphylococcus aureus in a concentration-dependent manner, and its inhibitory effect on S. aureus was higher than that of E. coli. Above all, this work provides a green method for the production of bioactive polysaccharide from sugarcane molasses.
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Affiliation(s)
- Li Ma
- Henan Provincial Key University Laboratory for Plant-Microbe Interactions, College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Xueliang Guo
- Henan Provincial Key University Laboratory for Plant-Microbe Interactions, College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Jiaoyang Yang
- Henan Provincial Key University Laboratory for Plant-Microbe Interactions, College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Xiangru Zeng
- Henan Provincial Key University Laboratory for Plant-Microbe Interactions, College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Kaili Ma
- Henan Provincial Key University Laboratory for Plant-Microbe Interactions, College of Biology and Food, Shangqiu Normal University, Shangqiu, China
| | - Lu Wang
- School of Biological Engineering, Henan University of Technology, Zhengzhou, China
| | - Qi Sun
- College of Life Sciences, Chongqing Normal University, Chongqing, China
| | - Zichao Wang
- School of Biological Engineering, Henan University of Technology, Zhengzhou, China
- National Engineering Laboratory, Key Laboratory of Henan Province, Henan University of Technology, Zhengzhou, China
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11
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Effect of an inorganic nitrogen source (NH 4) 2SO 4 on the production of welan gum from Sphingomonas sp. mutant obtained through UV-ARTP compound mutagenesis. Int J Biol Macromol 2022; 210:630-638. [PMID: 35513098 DOI: 10.1016/j.ijbiomac.2022.04.219] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/24/2022] [Accepted: 04/28/2022] [Indexed: 12/14/2022]
Abstract
As one of the most expensive extracellular polysaccharides, welan gum is widely used in biomedicine, food products, and petroleum because of its unique structure and excellent rheological properties. To reduce the cost of welan gum fermentation, together with (NH4)2SO4, which served as the sole nitrogen source, a high-welan-gum-producing mutant, B-8, screened through UV-ARTP compound mutagenesis was used. Under optimum conditions (C:N ratio 25:1, sucrose 50 g/L, (NH4)2SO4 4 g/L, and adding 8 mM NaCl at 32 h fermentation), the yield of welan gum and sucrose conversion were 18.86 g/L and 0.38 g/g, respectively, which were 98.95% and 137.50% higher than those achieved with the parent strain FM01, respectively. After the same treatment process, IN-welan (obtained with (NH4)2SO4) consumed less 95% ethanol, had higher molecular weight, and exhibited better rheological properties than ON-welan (obtained with beef extract). Transcriptome analysis revealed that (NH4)2SO4 could affect the synthetic pathway and monosaccharide content of welan gum by increasing bacterial chemotaxis and the availability of key intermediates. The fermentation performance of Sphingomonas sp. mutants could further be improved by providing several target genes to the mutants through metabolic engineering.
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12
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Kamer DDA, Gumus T, Palabiyik I, Demirci AS, Oksuz O. The fermentation-based production of gellan from rice bran and the evaluation of various qualitative properties of gum. Int J Biol Macromol 2022; 207:841-849. [PMID: 35358576 DOI: 10.1016/j.ijbiomac.2022.03.168] [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: 02/18/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 11/27/2022]
Abstract
The potential for the use of rice bran, an agricultural waste, as a substrate in the manufacture of gellan gum was examined. Using a standard strain of Sphingomonas paucimobilis (ATCC 31461) and rice bran substrate, gellan gum was produced under optimized conditions. The optimal yield of gellan gum using rice bran substrate was found to be 11.96 g L-1 with 5% glucose, 10% inoculum, and a mixing speed of 300 rpm. Native gum was found to have a consistency index of 2.00 Pa.sn. The viscosity of the gum was found to be extremely stable when exposed to thermal stress. Concerning the rheological characteristics, the Herschel-Bulkley model offered a more realistic representation of the flow characteristics of gum solutions. The synthesized gums were mostly composed of glucose, rhamnose, and glucuronic acid. The acetic acid content of gellan gums was 2.95%, while the molecular weight was 2.88 × 105 Da. Characterization of native gellan gums by UV-Vis spectroscopy, SEM, TEM and FTIR spectroscopy is also presented.
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Affiliation(s)
| | - Tuncay Gumus
- Department of Food Engineering, Tekirdag Namik Kemal University, 59030 Tekirdag, Turkey.
| | - Ibrahim Palabiyik
- Department of Food Engineering, Tekirdag Namik Kemal University, 59030 Tekirdag, Turkey
| | - Ahmet Sukru Demirci
- Department of Food Engineering, Tekirdag Namik Kemal University, 59030 Tekirdag, Turkey
| | - Omer Oksuz
- Department of Food Engineering, Tekirdag Namik Kemal University, 59030 Tekirdag, Turkey
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13
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Structural Characterization of Exopolysaccharide Produced by Leuconostoccitreum B-2 Cultured in Molasses Medium and Its Application in Set Yogurt. Processes (Basel) 2022. [DOI: 10.3390/pr10050891] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Sugarcane molasses is an agricultural by-product containing sucrose. In this study, the exopolysaccharide (M-EPS) produced by Leuconostoc citreum B-2 in molasses-based medium was characterized, optimized, and its application in set yogurt was investigated. The structure analysis, including gel permeation chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance, revealed that the M-EPS was a linear dextran composed of D-glucose units, which were linked by α-(1→6) glycosidic bonds with 19.3% α-(1→3) branches. The M-EPS showed a lower molecular weight than that produced from sucrose. The M-EPS was added into the set yogurt, and then the water holding capacity, pH, and microstructure of set yogurt were evaluated. Compared with the controls, the addition of M-EPS improved the water holding capacity and reduced the pH of set yogurt. Meanwhile, the structure of the three-dimensional network was also observed in the set yogurt containing M-EPS, indicating that M-EPS had a positive effect on the stability of set yogurt. The results provide a theoretical basis for the cost-effective utilization of sugarcane molasses.
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14
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Mahajan S, Yadav H, Rellegadla S, Agrawal A. Polymers for enhanced oil recovery: fundamentals and selection criteria revisited. Appl Microbiol Biotechnol 2021; 105:8073-8090. [PMID: 34609524 DOI: 10.1007/s00253-021-11618-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 10/20/2022]
Abstract
As the energy demand is escalating tremendously and crude oil being the primary energy source for at least the next two decades, the production of crude oil should be enhanced to meet the global energy needs. This can be achieved by either exploration of new oil fields for crude oil extraction or employing enhanced oil recovery (EOR) technology to recover the residual oil from existing marginal oil fields. The former method requires more capital investment and time; therefore, this review focuses on the latter. In general, the abandoned oil fields still have 50% of crude left which is unrecovered due to lack of technology. Hence, EOR came into existence after the conventional methods of recovery (primary and secondary recovery) were found to be inefficient and less economical. Nineteen percent of the EOR projects are based upon cEOR methods worldwide, of which more than 80% of projects use economically feasible polymer flooding process for oil recovery. Both synthetic and naturally derived polymers have been used widely for this purpose; however, many recent studies have shown the lower stability of synthetic polymers under extreme reservoir conditions of high salinity and temperature. Additionally, naturally derived polymers face microbial degradation as the major limitation. Therefore, a number of novel polymers are currently studied for their suitability as an efficient EOR polymer. Latest findings have also revealed that biopolymers play an important role in wettability alteration, pore evolution by bioplugging, and reducing fingering effect. Injection of biopolymers can also lead to the selective plugging of thief zones which redirects water flood to the inaccessible oil pores. Therefore, the current study focuses on such principle and mechanism of polymer flooding along with the reservoir and field characteristics which affects the polymer flooding. It also discusses the scope of biopolymer along with the screening criteria for use of novel polymers and strategies to overcome the problems during polymer flooding. KEY POINTS: • Discussion of macroscopic and microscopic mechanisms of polymer flooding. • Screening criteria of polymers prior to flooding are essential. • Biopolymers are eco-friendly and are applicable for a wide range of reservoir conditions.
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Affiliation(s)
- Sugandha Mahajan
- Department of Microbiology, Central University of Rajasthan, Bandarsindri Kishangarh, NH-8, Ajmer, Rajasthan, India
| | - Harender Yadav
- Department of Microbiology, Central University of Rajasthan, Bandarsindri Kishangarh, NH-8, Ajmer, Rajasthan, India
| | - Sandeep Rellegadla
- Department of Microbiology, Central University of Rajasthan, Bandarsindri Kishangarh, NH-8, Ajmer, Rajasthan, India
| | - Akhil Agrawal
- Department of Microbiology, Central University of Rajasthan, Bandarsindri Kishangarh, NH-8, Ajmer, Rajasthan, India.
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15
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Lin L, Zhang Z, Tang H, Guo Y, Zhou B, Liu Y, Huang R, Du L, Pang H. Enhanced sucrose fermentation by introduction of heterologous sucrose transporter and invertase into Clostridium beijerinckii for acetone-butanol-ethanol production. ROYAL SOCIETY OPEN SCIENCE 2021; 8:201858. [PMID: 34567584 PMCID: PMC8456130 DOI: 10.1098/rsos.201858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 08/31/2021] [Indexed: 05/12/2023]
Abstract
A heterologous pathway for sucrose transport and metabolism was introduced into Clostridium beijerinckii to improve sucrose use for n-butanol production. The combined expression of StSUT1, encoding a sucrose transporter from potato (Solanum tuberosum), and SUC2, encoding a sucrose invertase from Saccharomyces cerevisiae, remarkably enhanced n-butanol production. With sucrose, sugarcane molasses and sugarcane juice as substrates, the C. beijerinckii strain harbouring StSUT1 and SUC2 increased acetone-butanol-ethanol production by 38.7%, 22.3% and 52.8%, respectively, compared with the wild-type strain. This is the first report to demonstrate enhanced sucrose fermentation due to the heterologous expression of a sucrose transporter and invertase in Clostridium. The metabolic engineering strategy used in this study can be widely applied in other microorganisms to enhance the production of high-value compounds from sucrose-based biomass.
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Affiliation(s)
- Lihua Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Zhikai Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Hongchi Tang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Yuan Guo
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Bingqing Zhou
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Yi Liu
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
| | - Ribo Huang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Liqin Du
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzymatic Technology, College of Life Science and Technology, Guangxi University, Daxue Road No. 100, Nanning, Guangxi 530005, People's Republic of China
| | - Hao Pang
- Guangxi Key Laboratory of Bio-refinery, National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Daling Road No. 98, Nanning, Guangxi 530007, People's Republic of China
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16
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Altan Kamer DD, Gumus T, Palabiyik I, Demirci AS, Oksuz O. Grape pomace as a promising source for gellan gum production. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2020.106584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Ke C, Wei L, Wang M, Li Q, Liu X, Guo Y, Li S. Effect of NaCl addition on the production of welan gum with the UV mutant of Sphingomonas sp. Carbohydr Polym 2021; 265:118110. [PMID: 33966819 DOI: 10.1016/j.carbpol.2021.118110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/07/2021] [Accepted: 04/16/2021] [Indexed: 02/03/2023]
Abstract
Because of its excellent stability, non-toxicity, biodegradability and unique rheology, welan gum can be widely used in various fields, such as petroleum, biomedicine and food products. In this study, a high-yield mutant strain FM01-S09 was screened through two rounds of UV mutagenesis. Remarkably, the production of welan gum could be further increased by adding 4 mM NaCl at 32 h fermentation, reaching 30.12 ± 0.25 g/L (28.66% higher than no adding), and the NaCl-WG solution had stronger structural, impact resistance, and temperature resistance than H2O2-WG and WG solutions. Furthermore, the mechanism by which NaCl promotes welan gum synthesis was also investigated. It was found that cell membrane characteristics, intracellular microenvironment makeup, and key enzyme gene expression levels were significantly altered in different fermentation stages. Therefore, the addition of NaCl could effectively promote the growth and fermentation performance of Sphingomonas sp., providing a novel strategy for cost-effective welan gum production.
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Affiliation(s)
- Chengzhu Ke
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Lulu Wei
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Miao Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Qiwen Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Xiaoling Liu
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Yuan Guo
- National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning 530004, China
| | - Shubo Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China.
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18
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Zhao M, Zhang H, Xu X, Li S, Xu H. A strategy for the synthesis of low-molecular-weight welan gum by eliminating capsule form of Sphingomonas strains. Int J Biol Macromol 2021; 178:11-18. [PMID: 33636257 DOI: 10.1016/j.ijbiomac.2021.02.157] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 10/22/2022]
Abstract
Welan gum is widely used in food, concrete additives, and oil recovery. Here we changed the capsule form of Sphingomonas strains by knocked out the sortase gene (srtW). The obtained welan gum was mainly composed of mannose, glucose, rhamnose, and glucuronic acid at a molar ratio of 4.0:5.8:1.6:1, respectively. Meanwhile, the molecular weight of welan gum decreased sharply (about 68 kDa). Moreover, the low molecular weight (LMW) welan gum was characterized by FT-IR and NMR spectroscopy. The rheological results revealed that the LMW welan gum solution is a pseudoplastic fluid with a lower apparent viscosity. Furthermore, the oscillation test illustrated stable dynamic viscoelasticity within the temperature range of 5-68 °C and frequency range of 0.01-15 rad/s. To the best of our knowledge, this is the first report of LMW welan gum production and characterization. These results provide references for LMW welan gum applications, and likely applicable for other biopolymers production.
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Affiliation(s)
- Ming Zhao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Hao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Xiaoqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
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19
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Li H, Li K, Guo Z, Xue H, Li J, Ji S, Wang J, Zhu H. The Function of β-1,4-Glucuronosyltransferase WelK in the Sphingan WL Gum Biosynthesis Process in Marine Sphingomonas sp. WG. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2021; 23:39-50. [PMID: 32979138 DOI: 10.1007/s10126-020-09998-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/11/2020] [Indexed: 06/11/2023]
Abstract
The marine-derived polysaccharide WL gum produced by Sphingomonas sp. WG showed commercial utility potential in ink, food, and oil industries. A β-1,4-glucuronosyltransferase WelK was predicted to catalyze the transfer of glucuronic acid from UDP-glucuronic acid to glucosyl-α-pyrophosphorylpolyprenol intermediate in the WL gum biosynthesis process. Its function was evaluated by bioinformatical analysis, gene knocking out, and overexpressing strategies. Compared to the wild strain, the WL gum production and broth viscosity of the mutant ∆welK were decreased by 71.5% and 99.2% when cultured for 48 h. The gene disruption led to the failure of product preparation. Homologous expression of welK in the native organism can effectively improve WL gum production. When glucose concentration was 6.7%, the WL gum production by the welK-overexpressing strain cultured for 60 h and 84 h reached 32.65 and 43.13 g/L, 134.1%, and 114% of the wild strain. The polysaccharide composition and qRT-PCR analysis showed that the glucuronic acid content was closely related to the expression level of welK. Thus, WelK was proved to play a critical role in the WL gum synthesis and will be an attractive target for metabolic engineering. Our experiment provided a genetic manipulation method for the functional characterization of genes in Sphingomonas sp. WG.
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Affiliation(s)
- Hui Li
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Kehui Li
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Zhongrui Guo
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Han Xue
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Jing Li
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Sixue Ji
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China
| | - Jiqian Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China.
| | - Hu Zhu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), 66 Changjiang West Road, Qingdao, 266580, People's Republic of China.
- Engineering Research Center of Industrial Biocatalysis, Fujian Province Higher Education Institutes, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou, 350007, People's Republic of China.
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20
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Microbial production of value-added bioproducts and enzymes from molasses, a by-product of sugar industry. Food Chem 2020; 346:128860. [PMID: 33385915 DOI: 10.1016/j.foodchem.2020.128860] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022]
Abstract
Molasses is a major by-product of sugar industry and contains 40-60% (w/w) of sugars. The world's annual yield of molasses reaches 55 million tons. Traditionally, molasses is simply discharged or applied to feed production. Additionally, some low-cost and environmentally friendly bioprocesses have been established for microbial production of value-added bioproducts from molasses. Over the last decade and more, increasing numbers of biofuels, polysaccharides, oligosaccharides, organic acids, and enzymes have been produced from the molasses through microbial conversion that possess an array of important applications in the industries of food, energy, and pharmaceutical. For better application, it is necessary to comprehensively understand the research status of bioconversion of molasses that has not been elaborated in detail so far. In this review, these value-added bioproducts and enzymes obtained through bioconversion of molasses, their potential applications in food and other industries, as well as the future research focus were generalized and discussed.
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21
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Efficient biosynthesis of polysaccharide welan gum in heat shock protein-overproducing Sphingomonas sp. via temperature-dependent strategy. Bioprocess Biosyst Eng 2020; 44:247-257. [PMID: 32944865 DOI: 10.1007/s00449-020-02438-x] [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: 04/15/2020] [Accepted: 08/26/2020] [Indexed: 10/23/2022]
Abstract
Cell growth and product formation are two critical processes in polysaccharide welan biosynthesis, but the conflict between them is often encountered. In this study, a temperature-dependent strategy was designed for two-stage welan production through overexpressing heat shock proteins in Sphingomonas sp. The first stage was cell growth phase with higher TCA cycle activity at 42 °C; the second stage was welan formation phase with higher precursor synthesis pathway activity at 37 °C. The highest welan concentration 37.5 g/L was achieved after two-stage process. Ultimately, this strategy accumulated welan yield of 79.2 g/100 g glucose and productivity of 0.62 g/L/h at 60 h, which were the best reported results so far. The duration of fermentation was shortened. Besides, rheological behavior of welan gum solutions remained stable at wide range of temperature, pH, and NaCl. These results indicated that this approach efficiently improved welan synthesis.
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22
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Li Q, Zhou Y, Ke C, Bai Y, Liu X, Li S. Production of welan gum from cane molasses by Sphingomonas sp. FM01. Carbohydr Polym 2020; 244:116485. [DOI: 10.1016/j.carbpol.2020.116485] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/03/2020] [Accepted: 05/19/2020] [Indexed: 01/02/2023]
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23
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Liu X, Zhao M, Xu Z, Xu H, Li S. Construction of a Robust Sphingomonas sp. Strain for Welan Gum Production via the Expression of Global Transcriptional Regulator IrrE. Front Bioeng Biotechnol 2020; 8:674. [PMID: 32695762 PMCID: PMC7338795 DOI: 10.3389/fbioe.2020.00674] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/01/2020] [Indexed: 11/16/2022] Open
Abstract
Welan gum is a widely used microbial polysaccharide produced by Sphingomonas sp. However, an important factor hindering the expansion of its production is the maladaptation of strain to fermentation conditions. In this work, the global transcriptional regulator gene irre was selected as a stress-resistant element. And it was integrated into the site of the genomic carotene synthesis key enzyme gene crtB to construct a robust carotenoid-free welan gum producing strain. Fermentation with the recombinant strain effectively reduced the ethanol consumption and pigment content in the product. The tolerance temperature increased by 10°C without the need for controlling the pH. Under this fermentation condition, welan gum concentration could still reach 20.26 ± 0.25 g/L, which was 187.38% higher than that of the wild-type strain (7.05 ± 0.15 g/L). Transcriptome analysis showed that with the control of IrrE, more than 1000 genes that are involved in multiple pathways, including two-component system, bacterial chemotaxis, flagellar assembly, and cell cycle, exhibited changes at the transcriptional level and jointly allowed the strain to protect against environmental stresses.
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Affiliation(s)
- Xiaoliu Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Bioscience and Engineering, Hebei University of Economics and Business, Shijiazhuang, China
| | - Ming Zhao
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Zheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing, China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
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24
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Zhang S, Jiang H, Xue S, Ge N, Sun Y, Chi Z, Liu G, Chi Z. Efficient Conversion of Cane Molasses into Fructooligosaccharides by a Glucose Derepression Mutant of Aureobasidium melanogenum with High β-Fructofuranosidase Activity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13665-13672. [PMID: 31686508 DOI: 10.1021/acs.jafc.9b05826] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Fructooligosaccharides (FOSs) are excellent food ingredients or feed additives by stimulating probiotics. In this paper, a CREA gene encoding a glucose repressor in the β-fructofuranosidase producer Aureobasidium melanogenum 33 with high-level FOS biosynthesis was disrupted, and glucose repression in disruptant D28 was relieved. The disruptant D28 produced up to 2100 U/mL of β-fructofuranosidase activity, whereas the enzyme activities produced by parent strain 33 and complemented strain C11 were below 600 U/mL. The whole cells of the disruptant D28 was used to convert cane molasses into FOSs, and 0.58 g of FOSs/g of molasses sugar was synthesized from 350 g/L cane molasses sugar within 4 h. Results demonstrated that the industrial waste cane molasses can be efficiently converted into FOSs by the glucose derepression mutant D28 with high β-fructofuranosidase activity. This low-cost and environmentally friendly bioprocess has great potential applications in bioengineering and biotechnology for FOS production.
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25
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Dalsasso RR, Pavan FA, Bordignon SE, Aragão GMFD, Poletto P. Polyhydroxybutyrate (PHB) production by Cupriavidus necator from sugarcane vinasse and molasses as mixed substrate. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.07.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Barcelos MCS, Vespermann KAC, Pelissari FM, Molina G. Current status of biotechnological production and applications of microbial exopolysaccharides. Crit Rev Food Sci Nutr 2019; 60:1475-1495. [PMID: 30740985 DOI: 10.1080/10408398.2019.1575791] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Microbial exopolysaccharides (EPS) are an abundant and important group of compounds that can be secreted by bacteria, fungi and algae. The biotechnological production of these substances represents a faster alternative when compared to chemical and plant-derived production with the possibility of using industrial wastes as substrates, a feasible strategy after a comprehensive study of factors that may affect the synthesis by the chosen microorganism and desirable final product. Another possible difficulty could be the extraction and purification methods, a crucial part of the production of microbial polysaccharides, since different methods should be adopted. In this sense, this review aims to present the biotechnological production of microbial exopolysaccharides, exploring the production steps, optimization processes and current applications of these relevant bioproducts.
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Affiliation(s)
- Mayara C S Barcelos
- Laboratory of Food Biotechnology - Food Engineering, Institute of Science and Technology - UFVJM - Diamantina, Minas Gerais, Brazil
| | - Kele A C Vespermann
- Laboratory of Food Biotechnology - Food Engineering, Institute of Science and Technology - UFVJM - Diamantina, Minas Gerais, Brazil
| | - Franciele M Pelissari
- Laboratory of Food Biotechnology - Food Engineering, Institute of Science and Technology - UFVJM - Diamantina, Minas Gerais, Brazil
| | - Gustavo Molina
- Laboratory of Food Biotechnology - Food Engineering, Institute of Science and Technology - UFVJM - Diamantina, Minas Gerais, Brazil
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27
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Dai X, Gao G, Wu M, Wei W, Qu J, Li G, Ma T. Construction and application of a Xanthomonas campestris CGMCC15155 strain that produces white xanthan gum. Microbiologyopen 2018; 8:e00631. [PMID: 29656507 PMCID: PMC6391268 DOI: 10.1002/mbo3.631] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 01/19/2018] [Accepted: 02/28/2018] [Indexed: 11/14/2022] Open
Abstract
In the industrial production of xanthan gum using Xanthomonas campestris CGMCC15155, large amounts of ethanol are required to extract xanthan gum from the fermentation broth and remove xanthomonadin impurities. To reduce the amount of ethanol and the overall production cost of xanthan gum, a xanthomonadin‐deficient strain of CGMCC15155 was constructed by inserting the Vitreoscilla globin (vgb) gene, under the control of the LacZ promoter, into the region of the pigA gene, which is involved in xanthomonadin synthesis. The insertion of vgb inactivated pigA, resulting in the production of white xanthan gum. The lack of xanthomonadins resulted in a decreased yield of xanthan gum. However, the expression product of vgb gene, VHb, could increase the metabolism of X. campestris, which allowed the production of xanthan gum to reach wild‐type levels in the engineered strain. The yield, molecular weight, and rheological properties of the xanthan gum synthesized by the engineered and wild‐type bacteria were essentially the same. When the same volume of ethanol was used, the whiteness values of the xanthan gum extracted from engineered and wild‐type bacteria were 65.20 and 38.17, respectively. To extract xanthan gum with the same whiteness, three and seven times the fermentation volume of ethanol was required for the engineered and wild‐type strains, respectively. Thus, the engineered train reduced the requirement for ethanol in xanthan gum production by 133.3%. The results demonstrated that the engineered bacteria used less ethanol, thus reducing the downstream processing cost in xanthan gum production.
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Affiliation(s)
- Xiaohui Dai
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Ge Gao
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Mengmeng Wu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Weiying Wei
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Jianmei Qu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China
| | - Guoqiang Li
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China.,Tianjin Engineering Technology Center of Green Manufacturing Biobased Materials, Tianjin, China
| | - Ting Ma
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, China.,Tianjin Engineering Technology Center of Green Manufacturing Biobased Materials, Tianjin, China
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Genome sequencing and analysis of Alcaligenes faecalis subsp. phenolicus MB207. Sci Rep 2018; 8:3616. [PMID: 29483539 PMCID: PMC5827749 DOI: 10.1038/s41598-018-21919-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 02/08/2018] [Indexed: 11/12/2022] Open
Abstract
Bacteria within the genus Alcaligenes, exhibit diverse properties but remain largely unexplored at genome scale. To shed light on the genome structure, heterogeneity and traits of Alcaligenes species, the genome of a tannery effluent isolated Alcaligenes faecalis subsp. phenolicus MB207 was sequenced and assembled. The genome was compared to the whole genome sequences of genus Alcaligenes present in the National Centre for Biotechnology Information database. Core, pan and species specific gene sequences i.e. singletons were identified. Members of this genus did not portray exceptional genetic heterogeneity or conservation and out of 5,166 protein coding genes from pooled genome dataset, 2429 (47.01%) contributed to the core, 1193 (23.09%) to singletons and 1544 (29.88%) to accessory genome. Secondary metabolite forming apparatus, antibiotic production and resistance was also profiled. Alcaligenes faecalis subsp. phenolicus MB207 genome consisted of a copious amount of bioremediation genes i.e. metal tolerance and xenobiotic degrading genes. This study marks this strain as a prospective eco-friendly bacterium with numerous benefits for the environment related research. Availability of the whole genome sequence heralds an opportunity for researchers to explore enzymes and apparatus for sustainable environmental clean-up as well as important compounds/substance production.
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Two-step economical welan gum production by Sphingomonas sp. HT-1 from sugar industrial by-products. Carbohydr Polym 2017; 181:412-418. [PMID: 29253990 DOI: 10.1016/j.carbpol.2017.09.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/29/2017] [Accepted: 09/10/2017] [Indexed: 01/18/2023]
Abstract
A two-step fermentation strategy using glucose mother liquor (GML) for cell growth and xylose mother liquor (XML) for welan gum synthesis was used to alleviate uneconomic welan gum fermentation. This study revealed: (1) optimal initial GML concentration was 11.7g/L (10g/L sugars contained); (2) optimal XML feeding strategy was pseudo-exponential fed-batch and feeding time was 12thh-54thh, amounting to 25.7g/L XML (20g/L sugars contained); and (3) in a 7.5-L bioreactor, welan gum concentration was 22.68±0.50g/L and its yield reached 0.756g/g sugars with trace residual sugars. Compared with the cost of batch fermentation using glucose as sole carbon source, the final carbon source costs decreased by 61.40% and the welan gum yield increased by 50%. GML and XML can be used as inexpensive carbon sources for welan gum production with higher yield, giving them industrial application potential to produce value-added chemicals.
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30
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Effect of oxygen supply on milk-clotting activity expressed by Paenibacillus spp. strain BD3526. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Bioconversion of Welan Gum from Kitchen Waste by a Two-Step Enzymatic Hydrolysis Pretreatment. Appl Biochem Biotechnol 2017; 183:820-832. [PMID: 28365855 DOI: 10.1007/s12010-017-2466-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 03/22/2017] [Indexed: 12/26/2022]
Abstract
Kitchen waste (KW) is a worldwide issue, which can lead to environment pollution. Nevertheless, it is also a low-cost and sustainable resource for bio-production. Meanwhile, welan gum (WG) is one kind of the most important exopolysaccharide but with high material cost. The aim of this study was to adopt two-step enzymatic hydrolysis to improve the release and recovery of both sugar and protein in KW for subsequent WG production. As the results, the recovery rates of sugar and protein reached 81.07 and 77.38%, which were both satisfactory. After the conditions optimized in flasks, the welan fermentation was conducted in a 5-L fermentor, and the WG yield, utilization rates of reducing sugar and KDN, respectively, reached 5.57 g L-1, 94.25% and 61.96%. Moreover, the kinetic analyses demonstrated that the WG fermentation in KWH was a partly growth-associated process. The KW was successfully treated by fermentation for the bioconversion to WG.
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Xu X, Nie Z, Zheng Z, Zhu L, Zhan X. Production and Rheological Properties of Welan Gum Produced by Sphingomonas sp. ATCC 31555 with Different Nitrogen Sources. J Mol Microbiol Biotechnol 2017; 27:55-63. [PMID: 28092912 DOI: 10.1159/000452835] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/23/2016] [Indexed: 11/19/2022] Open
Abstract
This study aimed to investigate the effect of nitrogen sources on the production and rheological properties of welan gum produced by Sphingomonas sp. ATCC 31555. Six different nitrogen sources were used for ATCC 31555 fermentation, and 2 of these were further analyzed due to their more positive influence on welan gum production and bacterial biomass. Bacterial biomass, welan gum yield, welan viscosity, molecular weight, monosaccharide composition, acyl content, and welan structure were analyzed. Welan gum production and the biomass concentration of ATCC 31555 were higher in media containing NaNO3 and beef extract. Welan viscosity decreased at higher temperatures of 30-90°C, and it increased with a higher welan concentration. In the media containing NaNO3 (3 g·L-1), welan viscosity was higher at 30-70°C and a welan solution concentration of 6-10 g·L-1. With a reduced NaNO3 concentration, the molecular weight of welan gum and the molar ratio of mannose decreased, but the molar ratio of glucuronic acid increased. With different nitrogen sources, the acetyl content of welan gum differed but its structure was similar. NaNO3 and beef extract facilitated welan production. A reduced NaNO3 concentration promoted welan viscosity.
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Affiliation(s)
- Xiaopeng Xu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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Enhancement of welan gum production in Sphingomonas sp. HT-1 via heterologous expression of Vitreoscilla hemoglobin gene. Carbohydr Polym 2017; 156:135-142. [DOI: 10.1016/j.carbpol.2016.08.081] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 11/24/2022]
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Improvement Production of Hyaluronic Acid by Streptococcus zooepidemicus in Sugarcane Molasses. Appl Biochem Biotechnol 2016; 182:276-293. [PMID: 27900664 DOI: 10.1007/s12010-016-2326-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/03/2016] [Indexed: 11/27/2022]
Abstract
Microbial hyaluronic acid (HA) production has been preferred rather than extraction from animal tissue for medical and cosmetic applications. In this context, to obtain an economically competitive HA production by Streptococcus zooepidemicus, culture conditions were studied to improve the polymer production in sugarcane molasses. The highest HA production by S. zooepidemicus ATCC 39920 achieved was 2.825 g. L-1 in a 4.5 L bioreactor with controlled pH (8.0) and medium containing molasses (85.35 g.L-1 total sugar) pretreated with activated charcoal and yeast extract (50 g.L-1). The HA produced exhibited a high molecular weight of 1.35 × 103 kDa and the DPPH radical scavenging activity of the polymer at 1 g.L-1 was 41 %. The FTIR and UV-Vis spectra showed no substantial differences in the spectral pattern between produced and standard HA. This study is a promising strategy for sugarcane molasses application by producing high value-added products such as hyaluronic acid.
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Zhang W, Chen Z, Wu M, Shi Z, Zhu F, Li G, Ma T. Improved production of carotenoid-free welan gum in a genetic-engineered Alcaligenes sp. ATCC31555. Biotechnol Lett 2016; 38:991-7. [PMID: 26932903 DOI: 10.1007/s10529-016-2068-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/25/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs. RESULTS The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l(-1) compared to 21 g ± 0.4 g l(-1) in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties. CONCLUSIONS Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.
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Affiliation(s)
- Wenwen Zhang
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhaohui Chen
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Mengmeng Wu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhong Shi
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Feng Zhu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Guoqiang Li
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Ting Ma
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China.
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