JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2022
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IF 5.895
Yu Lu,Jie Liu,Zhenhua Li,Wenqing Li,Jing Liu,Linjuan Huang,Zhongfu Wang
Casein glycomacropeptide carries various O-glycan modifications, which, together with variations in the amino acid composition of the glycopeptide, may result in different biological activities. In this study, O-glycans of casein glycomacropeptide from bovine and caprine whey powder were qualitatively and quantitatively analyzed by LC-UV-ESI-MS/MS, and their immune activities and regulatory mechanisms were compared. O-Glycans’ total content was 1.54 times higher in bovine than in caprine glycomacropeptide. The glycoform H1N1S2 (H: hexose; N: N-acetylgalactosamine; and S: N-acetylneuraminic acid) accounted for nearly 50% of total glycomacropeptide O-glycans in bovine milk but less than 20% in caprine milk. Bovine glycomacropeptide glycosylation promoted the immune activity of RAW264.7 cells, which may be linked to a higher content of disialylated O-glycans. Glycomacropeptide from both milk sources significantly upregulated the mRNA expression of IL-1α, TNF-α, and IL-10 in RAW264.7 cells and activated the MAPK immunomodulatory signaling pathway. This study demonstrates the possible use of casein glycomacropeptide as an immunomodulatory agent.
研究领域:
食品科学
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免疫学
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生物化学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOTECHNOLOGY
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2024
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IF 4.1
Bowen Shen,Lin Zhang,Yu Zhou,Feifei Song,Shengping You,Rongxin Su,Wei Qi
5-Hydroxytryptophan (5-HTP), a precursor of the neurotransmitter serotonin in mammals, has demonstrated efficacy in treating various diseases such as depression, fibromyalgia and obesity. However, conventional biosynthesis methods of 5-HTP are limited by low yield and high reagent and process costs. In this study, the strain C1T7-S337A/F318Y with optimized promoter distribution was obtained, and the 5-HTP yield was 60.30 % higher than that of the initial strain. An efficient fermentation process for 5-HTP synthesis was developed using strain C1T7-S337A/F318Y with whey powder as a substrate for cell growth and inducer production. Shake flask fermentation experiments yielded 1.302 g/L 5-HTP from 2.0 g/L L-tryptophan (L-Trp), surpassing the whole-cell biocatalysis by 42.86 %. Scale-up to a 5 L fermenter further increased the yield to 1.649 g/L. This fermentation strategy substantially slashed reagent cost by 95.39 %, providing a more economically viable and environmentally sustainable route for industrial biosynthesis of 5-HTP. Moreover, it contributes to the broader utilization of whey powder in various industries.
研究领域:
生物工程
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微生物学
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医药化学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2025
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IF 9.8
Zhuoning Cao,Chengqiang Li,Hong Jiang,Francesco Secundo,Xiangzhao Mao
β- N -acetylhexosaminidases garnered attention in the enzymatic synthesis of lacto- N -triose II (LNT2) as the backbone precursor of human milk oligosaccharides (HMOs). In this study, β- N -acetylglucosaminidases Hex(Sv)-2557 from Streptomyces violascens ATCC 27968 was engineered based on a stabilizing intermediate strategy to improve its transglycosylation activity for LNT2 synthesis. A mutant Hex(Sv)-2557(D297K) with a transglycosylation activity of 38.4 U/mg with p NP-GlcNAc −1.9-fold higher than that of Hex(Sv)-2557– was obtained and characterized. Instead, the hydrolase activity of the mutant was 73 % lower compared to the wild-type enzyme. Importantly, the mutant can use N -acetyl chitobiose (GlcNAc 2 ) as the donor for LNT2 synthesis. The LNT2 yield of 14.85 % was obtained when the synthetic reaction, catalyzed by the mutant Hex(Sv)-2557(D297K), started from whey powder and GlcNAc 2 -prepared from chitin by chitinase ChiA and ChiB. This study has altered the donor for the action by directed modification and promoting the high-value utilization of whey powder and chitin.
研究领域:
生物化学
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酶工程
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食品科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
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IF 5.7
Chengqiang Li,Zhuoning Cao,Hong Jiang,Francesco Secundo,Xiangzhao Mao
β-N-Acetylhexosaminidases have attracted much attention in the enzymatic synthesis of lacto-N-triose II (LNT2) as a backbone precursor of human milk oligosaccharides (HMOs). In this study, a novel glycoside hydrolase (GH) 20 family β-N-acetylhexosaminidase, FlaNag2353, from Flavobacterium algicola was biochemically characterized and applied to synthesize LNT2. FlaNag2353 displayed optimal activity to p-nitrophenyl N-acetyl-β-d-glucosaminide (pNP-GlcNAc) at 40 °C and pH 8.0. In addition to its excellent hydrolysis activity toward pNP-GlcNAc and chitooligosaccharides, FlaNag2353 showed trans-glycosylation activity. Under conditions of pH 9.0 and 55 °C for 2 h and utilizing 200 mM lactose and 10 mM pNP-GlcNAc, FlaNag2353 synthesized LNT2 with a conversion ratio of 4.15% calculated from pNP-GlcNAc. Moreover, when applied to LNT2 synthesis with 10 mM pNP-GlcNAc and 9.7% (w/v) industrial waste whey powder, FlaNag2353 achieved a conversion ratio of 2.39%. This study has significant implications for broadening the applications of GH20 β-N-acetylhexosaminidases and promoting the high-value utilization of whey powder.
研究领域:
生物化学
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酶学
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食品科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2020
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IF 7.539
Guoyan Zhang,Hossain M. Zabed,Junhua Yun,Jiao Yuan,Yufei Zhang,Yang Wang,Xianghui Qi
In this study, a new strain of Lactobacillus plantarum (CY.6) was identified and its L-arabinose isomerase (L-AI) encoding gene ( ara A) was overexpressed in Escherichia coli BL21 for the biosynthesis of D-tagatose from milk whey powders (WP). Whole-cell biotransformation of lactose in WP into D-tagatose was done by three technological approaches, including 100%, 50% and 0% hydrolysis of lactose in WP before biotransformation, where simultaneous saccharification and biotransformation (SSB, 0% prior hydrolysis of lactose) produced maximum amounts of D-tagatose. Two-stage SSB provided 73.6% conversion efficiency (based on D-galactose) and 36.8% (in term of lactose), with 51.5 g/L of D-tagatose after 96 h, while concentration of D-tagatose produced after first stage was 34.4 g/L. Yield and volumetric productivity of D-tagatose after two-stage SSB were found to be 0.26 g/g of WP (0.37 g/g of lactose, 0.74 g/g of D-galactose produced from lactose) and 0.54 g/L/h, respectively.
研究领域:
生物技术
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微生物学
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食品工程
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酶学
✓ 已验证
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）