Fermentation-Basel
·
2022
·Vol. 8
·期 7
·321
·
IF 5.123
Haixing Li,Tianyi Sun,Mengya Jia,Lingqin Wang,Cheng Wei,Jinfeng Pei,Zhiyu Lin,Shuixing Wang
There is a recent trend of using lactic acid bacteria for the production of gamma-aminobutyric acid (GABA). This study described a method that combines fermentation and self-buffered whole-cell catalysis for the efficient production of GABA usingLevilactobacillus brevisCD0817. Upon the completion of GABA fermentation, cells were recovered to conduct whole-cell catalysis by which the substrate L-glutamic acid was catalytically decarboxylated to GABA. L-glutamic acid itself maintained the acidity essential for decarboxylation. To maximize the whole-cell catalysis ability, the effects of the cell culture method, catalysis temperature, catalysis time, cell concentration, and L-glutamic acid dosage were investigated. The results illustrate that the cells that were cultivated for 16 h in a fermentation medium supplemented with 20.0 g/L of glucose were the most suitable for the whole-cell catalytic production of GABA. At 16 h, the fermentative GABA content reached 204.2 g/L. Under optimized whole-cell catalytic conditions (temperature 45.0 °C, time 12.0 h, wet cells 25.0 g/L, and L-glutamic acid 120.0 g/L), 85.1 g/L of GABA was obtained, with 3.7 ± 0.9 g/L of substrate residue. GABA was recovered from the system by sequentially performing rotary vacuum evaporation, precipitation with ethanol, filtration with filter paper, and drying. The purity of the GABA product reached 97.1%, with a recovery rate of 87.0%. These data suggest that the proposed method has potential applications in the production of GABA.Keywords:gamma-aminobutyric acid;Levilactobacillus brevisCD0817;fermentation;whole-cell catalysis
研究领域:
微生物学
·
生物工程
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DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2022
·
IF 6.064
Yang Rongling,Wang Yu,Zhao Xiangjie,Tong Zheng,Zhu Qianlin,He Xiaoxi,Wang Zhaoyu,Luo Hongzhen,Fang Fang
Salidroside, the main bioactive compound isolated from the plant source of Rhodiola rosea L, possesses broad-spectrum pharmacological activities, but suffers from the low cell membranes permeability and alimentary absorption due to its high polarity. Therefore, a whole-cell catalytic strategy for the synthesis of salidroside esters was explored to improve its lipophilicity. The results showed that Aspergillus oryzae demonstrated the highest biocatalytic activity among the microbial strains tested. For the synthesis of salidroside caprylate, the optimum conditions of reaction medium, Aspergillus oryzae amount, molar ratio of vinyl caprylate to salidroside and reaction temperature were acetone, 30 mg/ml, 10°C and 40°C, respectively. Under these conditions, the initial reaction rate was 15.36 mM/h, and substrate conversion and regioselectivity all reached 99%. Moreover, the results indicated that although various 6′-monoesters derivatives of salidroside were exclusively obtained with excellent conversions (96%–99%), the reaction rate varied greatly with different chain-length acyl donors. This study details an efficient and cost-effective biocatalytic approach for the synthesis of salidroside esters by using Aspergillus oryzae as a catalyst for the first time. Considering the whole cell catalytic efficiency and operational stability, this strategy may provide a new opportunity to develop green industrial processes production for ester derivatives of salidroside and its analogues.
研究领域:
药理学
·
生物化学
·
工业微生物学
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产品关联
DOI
PubMed
高影响因子
CATALYSIS COMMUNICATIONS
·
2013
·
IF 2.915
Hong-De Yan,Qun Zhang,Zhao Wang
A lipase from Aspergillus oryzae WZ007 exhibited high esterification activities toward a series of short-chain acids and alcohols. Moreover, it displayed a strong tolerance for high substrate concentration of up to 2.0 M and presented a highest initial rate of 276 mmol·L − 1 ·h − 1 at this concentration. After a reaction time of 48 h, the conversion rates of acids were higher than 80% for the synthesis of a majority of heptanoic acid esters, some octanoic acid esters and n -propyl hexanoate. These results implied that A. oryzae WZ007 lipase was a promising biocatalyst in the production of flavor esters.
研究领域:
生物化学
·
食品科学
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产品关联
DOI
高影响因子
CELLULOSE
·
2023
·Vol. 30
·期 14
·8997-9012
·
IF 5.7
Peng Qiao,Chen Yi,Fan Guozhi,Song Guangsen,Cheng Qunpeng
Holocellulose extracted from wheat straw was acetylated and used to prepare biodegradable composite film. An efficient catalytic system for the acetylation of holocellulose was explored by evaluating the influence of type and the amount of catalyst on the degree of substitution (DS) of acetylated holocellulose (AHC). The DS of AHC reached 2.16 when using p -toluene sulfonic acid and sulfuric acid as co-catalyst. AHC was further used to prepare composite film in the presence of reinforcer and plasticizer, and the influence of DS value of AHC on the properties of composite film was investigated. The tensile strength, elongation at break and Young’s modulus of the composite film derived from AHC with DS value of 2.16 were 9.51 MPa, 82.66% and 54.43 MPa when using chitosan and polyvinyl alcohol as the reinforcers, sorbitol and glycerol as the plasticizers. The UV-blocking performance and degradation of AHC-based composite film were also performed. It was found that about 90% UV light was absorbed and 59.2% was decomposed after biodisintegrating for 30 d. The excellent comprehensive performance of the AHC-based composite film reveals application prospect of holocellulose in the field of biodegradable materials.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
GREEN CHEMISTRY
·
2017
·Vol. 19
·期 16
·3844-3850
·
IF 9.125
Yucai He,Yun Ding,Cuiluan Ma,Junhua Di,Chunxia Jiang,Aitao Li
One-pot furfuralcohol (FOL) production via dehydration of corncob-derived xylose followed by bioreduction of furfural has been described. The synthesized biocompatible solid acid catalyst SO42−/SnO2-attapulgite has been characterized and used for the dehydration of xylose-rich hydrolysate, and the highest furfural yield of 44% is achieved when employing 3.6 wt% catalyst loading at 170 °C for 20 min. The recombinant Escherichia coli CCZU-A13 harboring a NADH-dependent reductase (SsCR) is found to catalyze the bioreduction of furfural to FOL, the whole-cell catalyst could tolerate as high as 300 mM furfural substrate to give 221 mM FOL after 12 h of reaction under the optimum conditions (1.0 mM glucose per mM furfural, 30 °C, pH 6.5, 0.1 g wet cells per mL). The two processes are successfully combined in a one-pot manner to transform the xylose-rich hydrolysate to furfural, and then to FOL with 44% yield based on the starting material xylose (100% FOL yield for the bioreduction step). Finally, recycling experiments for the carrageenan immobilized whole-cell and solid acid catalyst in one-pot FOL production are conducted; both catalysts show excellent recyclability and no obvious decrease in activity is detected after 5 cycles of reaction. The developed one-pot chemo-enzymatic approach is greatly useful for practical green FOL production from renewable biomass resources.
研究领域:
生物化学
·
绿色化学
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产品关联
DOI
高影响因子
Catalysts
·
2020
·Vol. 10
·期 9
·947
·
IF 3.52
Hongjie Hui,Yajun Bai,Tai-Ping Fan,Xiaohui Zheng,Yujie Cai
Putrescine, a biogenic amine, is a highly valued compound in medicine, industry, and agriculture. In this study, we report a whole-cell biocatalytic method inEscherichia colifor the production of putrescine, using L-arginine as the substrate. L-arginine decarboxylase and agmatine ureohydrolase were co-expressed to produce putrescine from L-arginine. Ten plasmids with different copy numbers and ordering of genes were constructed to balance the expression of the two enzymes, and the best strain was pACYCDuet-speB-speA. The optimal concentration of L-arginine was determined to be 20 mM for this strain. The optimum pH of the biotransformation was 9.5, and the optimum temperature was 45 °C; under these conditions, the yield of putrescine was 98%. This whole-cell biocatalytic method appeared to have great potential for the production of putrescine.Keywords:L-arginine;putrescine;Escherichia coli;whole-cell catalysis;co-expression
研究领域:
生物技术
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生物化学
·
微生物学
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2018
·
IF 3.412
Xiao-Feng Li,Tingting Yuan,Haixia Xu,Xuan Xin,Guanglei Zhao,Hui Wu,Xinglong Xiao
Puerarin, an important isoflavonoid from the edible root of Pueraria lobata, shows multiple bioactivities but suffers from low bioavailability. In this study, a new whole-cell catalytic method for acylation modification of puerarin was developed. Among the 12 strains tested, Aspergillus oryzae showed the highest catalytic activity and selectively catalyzed acylation of puerarin at the 6″-hydroxyl group. The organic solvents used significantly influenced the catalytic efficiency of the cells. In the green solvent 2-methyltetrahydrofuran, the reaction showed high substrate conversion (92.5%) and regioselectivity (95.8%), with results similar to those with tetrahydrofuran (94.2% and 98.5%, respectively) under optimal conditions. The monoester products showed higher liposolubility in comparison to puerarin, and those with C3–C8 fatty acid chain lengths showed evidently improved antioxidant activity toward erythrocyte hemolysis. Considering the operational stability of the cells and efficiency of the scaled-up reactions, this method is efficient and cost effective, with promising applications in the health food industry.
研究领域:
药理学
·
生物化学
·
食品科学
✓ 已验证
DOI
PubMed
高影响因子
Microbial Biotechnology
·
2022
·Vol. 15
·期 5
·1610-1621
·
IF 6.575
Xing Liu,Xiao Han,Yuan Peng,Chunlin Tan,Jing Wang,Hongsong Xue,Ping Xu,Fei Tao
Summary 3, 4-Dihydroxyphenyl- l -alanine ( l -DOPA) is a compound of high medical value and is considered effective as a treatment for Parkinson’s disease. Currently, bioproduction of l -DOPA is mainly carried out by whole-cell catalysis mediated by recombinant Escherichia coli carrying heterogeneous tyrosine phenol lyase. Vibrio natriegens is increasingly attracting attention owing to its superiority, including extremely rapid growth and high soluble protein expression capacity. In this study, we attempt to develop an efficient whole-cell catalyst for l -DOPA production using V. natriegens as the chassis. The maximum soluble protein expression by V. natriegens was accomplished in 4 h at 37°C, which was equivalent to that achieved by E. coli in 16 h at 16°C. Furthermore, the maximum productivity reached over 10.0 g l −1 h −1 in the early stage of biocatalysis, nearly two-fold higher than previously reported. Approximately 54.0 g l −1 l -DOPA was obtained with a catechol conversion rate greater than 95%. In conclusion, V. natriegens displays advantages, including rapid protein expression and catalytic rate in the catalysis process for l -DOPA production. These findings strongly suggest that V. natriegens has remarkable potential as a whole-cell catalysis chassis for the production of valuable chemicals.
研究领域:
生物工程
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医学
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微生物学
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产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 3.8
Ying-Ying Xu,Bin Zhang,Jie Bao
Industrial production of cadaverine primarily relies on whole-cell catalysis of lysine using engineered Escherichia coli as host cells. The growing interest in cadaverine as a monomer of biobased polyamides requires inexpensive, non-food carbohydrate feedstock for its bioproduction, rather than using food-derived sugars as feedstock. This study used corncob residue as the starting carbohydrate feedstock followed by enzymatic hydrolysis to obtain the sugars. Since E. coli was not tolerant to even minor inhibitor residues in corncob residue hydrolysate, the robust Corynebacterium glutamicum was used as the host bacterium followed by the metabolic modifications of secretory expression of lysine decarboxylase via Ncgl1289 and cgR_0949 , and cadaverine degradation pathway knockout. The final whole-cell catalysis of C. glutamicum recombinant using corncob hydrolysate as carbohydrate feedstock achieved a record-high 78.19 g/L of cadaverine with a conversion yield of 91%.
研究领域:
工业微生物学
·
生物工程
·
代谢工程
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产品关联
DOI
高影响因子
AICHE JOURNAL
·
2022
·Vol. 69
·期 3
·e18005
·
IF 4.167
Xia Hua,Jian Han,Xin Zhou,Yong Xu
Oxygen, as a terminal electron acceptor, is an essential substrate in the aerobic bio-oxidation process, affecting bacterial vitality and bio-oxidation performance. In this study, a newfangled platform biotechnology of sealed-oxygen supply bioreactor (SOS-BR) was developed by improving gas pressure to significantly intensify oxygen transfer rate to resolve the formidable barriers of aerobic catalysis. In virtue of SOS-BR, the bio-productivity was greatly improved for three representative substrates (xylose, furfural, and glycerol) bio-oxidation with the whole-cell catalysis of Gluconobacter oxydans . The determination of oxygen transfer coefficient ( K L α ) established an upgraded theoretical dynamic model for gas pressure intensification biosystem. Additionally, viscosity measurement and combined pressure control strategy explained the inflection point phenomenon of productivity and confirmed the intensify mechanism. The smart strategy of significantly intensifying oxygen transfer provided insightful ideas for overcoming the stubborn obstacle of obligate aerobic catalysis, and further promoted the development and industrial practicability of bio-oxidation.
研究领域:
生物工程
·
微生物学
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产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2023
·Vol. 107
·期 21
·6497-6506
·
IF 5
Liu Kun,Liu Yan,Li Xiangfei,Zhang Xiushan,Xue Zhenglian,Zhao Ming
Abstract The whole-cell catalysis strategy of alpha-ketoglutaric acid (α-KG) production from L-glutamic acid (L-Glu) using recombinant Escherichia coli , in which L-glutamate oxidase (LGox) was over-expressed, has replaced the traditional chemical synthesis strategy. However, large amounts of toxic by-product, H 2 O 2 , should be eliminated through co-expressing catalase (Cat), thus severely increasing burden in cells. To efficiently and economically produce α-KG, here, the genes SpLGox (from Streptomyces platensis NTU3304) and SlCat (from Streptomyces lividans TK24) were inserted into the low-dosage-IPTG (Isopropyl β-D-Thiogalactoside) inducible expression system, constructed in our previous work, in E. coli , respectively. Besides, a double-strain catalysis system was established and optimized to produce α-KG, and the productivity of α-KG was increased 97% compared with that through single strain catalysis. Finally, a double-strain cultivation strategy was designed and employed to simplify the scale-up fermentation. Using the optimized whole-cell biocatalyst conditions (pH 7.0, 35 °C), majority of the L-glutamic acid was transformed into α-KG and the titer reached 95.4 g/L after 6 h with the highest productivity at present. Therefore, this strategy may efficiently and cost-effectively produce α-KG, enhancing its potential for industrial applications. Key points
• SpLGox and SlCat were over-expressed to catalyze L-Glu to α-KG and eliminate by-product H
2
O
2
, respectively.
• Double-strain cultivation and catalysis system can efficiently and cost-effectively produce α-KG from L-Glu.
研究领域:
生物工程
·
代谢工程
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LETTERS IN APPLIED MICROBIOLOGY
·
2021
·Vol. 72
·期 4
·399-407
·
IF 2.858
Wang N.,Xu Y.,Peng C.,Wang X.,Wei Y.,Li K.,Wang S.,Xu A.,Gao J.
A strain NQ1, which showed efficient asymmetric reduction of 3,5‐bis(trifluoromethyl) acetophenone (BTAP) to enantiopure (S)‐[3,5‐bis(trifluoromethyl)phenyl]ethanol ((S)‐BTPE), which is the key intermediate for the synthesis of a receptor antagonist and antidepressant, was isolated from a soil sample. Based on its morphological and internal transcribed spacer sequence, the strain NQ1 was identified to be Rhodotorula mucilaginosa NQ1. Some key reaction parameters involved in the bioreduction catalyzed by whole cells of R. mucilaginosa NQ1 were subsequently optimized, and the optimized conditions for the synthesis of (S)‐BTPE were determined to be as follows: 5·0 ml phosphate buffer (200 mmol l−1, pH 7·0), 80 mmol l−1 of BTAP, 250 g (wet weight) l−1 of resting cell, 35 g l−1 of glucose and a reaction for 18 h at 30°C and 180 rev min−1. The strain NQ1 exhibited a best yield of 99% and an excellent enantiomeric excess of 99% for the preparation of (S)‐BTPE under the above optimal conditions, and could also asymmetrically reduce a variety of bulky prochiral carbonyl compounds to their corresponding optical hydroxyl compound with excellent enantioselectivity. These results indicated that R. mucilaginosa NQ1 had a good capacity to reduce BTAP to its corresponding (S)‐BTPE, and might be a new potential biocatalyst for the production of valuable chiral hydroxyl compounds in industry.
研究领域:
微生物学
·
生物催化
·
有机化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）