BIORESOURCE TECHNOLOGY
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2022
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IF 11.889
Xiaolan Li,Yufei Zhang,Hossain M. Zabed,Junhua Yun,Guoyan Zhang,Mei Zhao,Yuvaraj Ravikumar,Xianghui Qi
d -Arabitol is a top value-added compound with wide applications in the food, pharmaceutical and biochemical industries. Nevertheless, sustainable biosynthesis of d -arabitol is limited by lack of efficient strains and suitable fermentation process. Herein, metabolic engineering and process optimization were performed in Zygosaccharomyces rouxii to overcoming these limitations. Adopting systems metabolic engineering include enhancement of innate biosynthetic pathway, supply of precursor substrate d -ribulose-5P and cofactors regeneration, a novel recombinant strain ZR-5A with good performance was obtained, which boosted d -arabitol production up to 29.01 g/L, 59.31 % higher than the parent strain. Further with the optimum medium composition and fed-batch fermentation, the strain ZR-5A finally produced 149.10 g/L d -arabitol with the productivity of 1.04 g/L/h, which was the highest titer ever reported by Z.rouxii system. This is the first report on the use of metabolic engineering to construct Z. rouxii chassis for the sustainable production of d -arabitol.
研究领域:
生物技术
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代谢工程
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发酵技术
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生物化工
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2023
·Vol. 415
·期 22
·5353-5363
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IF 4.3
Yu Yang,Pai Nanya,Chen Xiaoya,Wang Baoling,Gao Shulin,Ge Dandan
A new type of hexafluorobutanol (HFB) primary alcohol ethoxylate (AEO)-based supramolecular solvent (SUPRAS) with density higher than water was prepared for the first time. HFB acted as AEO micelle-forming agent and density-regulating agent for SUPRAS formation. The prepared SUPARS was applied as extraction solvent for vortex-assisted direct microextraction of malachite green (MG) and crystal violet (CV) from lake sediment followed by high-performance liquid chromatographic determination. In the present work, SUPRASs prepared from AEO with different carbon chains as the amphiphiles and various coacervation agents were investigated. SUPARS formed from MOA-3 and HFB provided better extraction efficiency in comparison with other SUPRASs. Parameters influencing the extraction recovery of target analytes including the type and volume of AEO, volume of HFB, and vortex time were investigated and optimized. Under optimized conditions, linearity in the range of 2.0–400 μg g −1 for MG and 2.0–500 μg g −1 for CV with a correlation coefficient higher than 0.9947 was obtained. Limits of detection of 0.5 μg g −1 and relative standard deviations in the range of 0.9–5.8% were obtained. Compared to conventional extraction techniques for analysis of analytes in solid samples, the proposed method reduced sample usage and eliminated a primary extraction process by using a toxic organic solvent. The proposed method is simple, fast, and green and can be used for the analysis of target analytes in solid samples. Graphical Abstract
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
POSTHARVEST BIOLOGY AND TECHNOLOGY
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2022
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IF 6.751
Hua Huang,Ling Wang,Xu Xiang,Fangcheng Bi,Zhaoqi Zhang
Litchi fruit is susceptible to pericarp browning after harvest, which is regulated by the oxidation of polyphenols and membrane lipids during storage. Cuticular waxes form the outermost lipid layer covering plant surfaces, and their changes in response to pericarp browning in litchi remain unclear. In this study, changes in morphological appearance and chemical composition of cuticular waxes, and expression of their associated biosynthesis regulatory genes in litchi were comprehensively investigated. In terms of pericarp microstructure, cuticular variations, such as wrinkled lines with “tooth-like” cuticular ridges, appeared on the epidermal cell surface. Following pericarp browning, the protruding nano-ridges were damaged, resulting in a disturbed appearance. Parallel to the appearance of morphological changes, we observed a 2.3-fold increase in cuticular waxes in the browned pericarp when compared with fresh fruit. Concerning chemical compositions, slight changes in the cyclic constituents were observed, whereas the synthesis of very-long-chain fatty acids , primary alcohols, aldehydes, and n -alkanes with carbon chains greater than C 26 appeared to be stimulated in the browned pericarp. Correspondingly, similar increased trends were detected in the relative gene expression levels of LcLACS1/2 , LcCER2 , LcKCR1 , LcHACD , and LcECR in fatty acid elongation, LcCER1 in n -alkanes, and LcFAR1 in primary alcohols. These results indicated that changes in surface microstructure modifications and the increase in biosynthesis of cuticular waxes, particularly the very-long-chain aliphatic components, occurred in response to the browning of litchi fruit during storage. Accordingly, surface cuticular waxes might also play an important role in regulating the browning of fruits during storage.
研究领域:
植物科学
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食品科学
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分子生物学
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产品关联
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
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2022
·Vol. 103
·期 4
·1974-1980
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IF 4.125
Hengtao Tang,Zhi Chen,Yu Shao,Xin Ju,Liangzhi Li
BACKGROUND The fermentation valorization of two main lignocellulosic monosaccharides, glucose and xylose, is extensively developed; however, it is restricted by limited yield and process complexity. An in vitro enzymatic cascade reaction can be an alternative approach. RESULTS In this study, a three-stage, five-enzyme cascade was developed to convert pretreated biomass to valuable chemicals. First, a ribose-5-phosphate isomerase B mutant isomerized xylose to d -xylulose with high substrate specificity, and a d -arabinose dehydrogenase continued to reduce d -xylulose to d -arabitol. Simultaneously, glucose was utilized for the coenzyme regeneration catalyzed by a glucose dehydrogenase, generating useful gluconic acid and achieving 73% of total conversion rate after 36 h. Then, six kinds of pretreated biomass lignocellulose were hydrolyzed by cellulase and hemicellulase, and corn cob was identified as the initial substrate for providing the highest monosaccharide content. A 65% conversion rate of the lignocellulosic xylose was obtained after 24 h. CONCLUSIONS This study presents a proof of concept to convert main lignocellulosic monosaccharides systematically by an enzymatic cascade at stoichiometric ratio. © 2022 Society of Chemical Industry.
研究领域:
生物技术
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生物化工
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酶学
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产品关联
DOI
PubMed
高影响因子
Small
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2024
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IF 13
Chaoxiang Chen,Xueping Pan,Mengdi Sun,Jialin Wang,Xueqi Su,Tianyu Zhang,Yulei Chen,Daren Wu,Jian Li,Shuqi Wu,Xiaomei Yan
Extracellular vesicles (EVs) are recognized as potential candidates for next-generation drug delivery systems. However, the inherent cancer-targeting efficiency is unsatisfactory, necessitating surface modification to attach cell-binding ligands. By utilizing phospholipase D from Streptomyces in combination with maleimide-containing primary alcohol, the authors successfully anchored ligands onto milk-derived EVs (mEVs), overcoming the issues of ligand leakage or functional alteration seen in traditional methods. Quantitative nano-flow cytometry demonstrated that over 90% of mEVs are effectively modified with hundreds to thousands of ligands. The resulting mEV formulations exhibited remarkable long-term stability in conjugation proportion, ligand number, size distribution, and particle concentration, even after months of storage. It is further shown that conjugating transferrin onto mEVs significantly enhanced cellular uptake and induced pronounced cytotoxic effects when loaded with paclitaxel. Overall, this study presents a highly efficient, stable, cost-effective, and scalable ligand conjugation approach, offering a promising strategy for targeted drug delivery of EVs.
研究领域:
药学
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生物技术
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癌症研究
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药物递送
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）