JOURNAL OF DAIRY SCIENCE
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2013
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IF 2.566
Liang Li,Ying Ma
The influence of fatty acids on the β-oxidation system and thioesterase of Lactococcus lactis was investigated in this study. The results showed that fatty acids (C8:0–C16:0) significantly inhibited the growth of Lactococcus lactis , and laurate (C12:0) had the highest bactericidal effects. We detected the maximum activity of β-oxidation at different incubation times (8, 12, and 18 h) to be 6.460, 7.751, and 8.203, respectively, and the maximum activity of thioesterase at different incubation times (8, 12, and 18 h) to be 19.498, 27.180, and 12.800, respectively. Fatty acids were seen to induce the β-oxidation system and activity of thioesterase; decanoic acid (C10:0) and palmitic acid (C16:0) were also seen to induce the β-oxidation system of Lactococcus lactis , but the induced ability was significantly different. Octanoic acid (C8:0) and palmitic acid (C16:0) were seen to induce thioesterase activity in Lactococcus lactis . When 1 m M palmitic acid (C16:0) was added to M17 broth, the activity of thioesterase increased 5-fold after 2 min; however, adding octanoic acid (C8:0) changed the activity little. Evidence showed that the ability to induce the β-oxidation system and thioesterase activity was related to the fatty acids’ chain lengths.
研究领域:
微生物学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
Food Bioscience
·
2022
·
IF 5.318
Caixia Chen,Guiguang Cheng,Yaping Liu,Yongxin Yi,Dongjie Chen,Lu Zhang,Xuejiao Wang,Jianxin Cao
Sour bamboo shoot is a popular traditional fermented vegetable in southern China. The current study aims to clarify the relationship among physicochemical properties, flavor, and microbial compositions of sour bamboo shoots during fermentation. Four organic acids (OAs) were considered to be the main acids in sour bamboo shoots. At least 7 volatile compounds (OAV >1) were identified as the characteristic aroma substances, especially p -cresol, which accounted for the sour odor of sour bamboo shoots. The microbial community showed that Firmicutes and Proteobacteria were the dominant phyla, while Lactococcus and Lactobacillus were the dominant genera in sour bamboo shoots. Correlation analysis indicated that Firmicutes positively correlated with p -cresol, phenol , 2-methoxy-phenol, malic acid , total titratable acidity (TTA), and some OAs. Lactococcus was positively correlated with phenol, 2-methoxy-phenol, benzyl alcohol, TTA, some OAs, and amino acids (AAs). This study provided a theoretical basis for screening indigenous aroma-producing microorganisms as the starter of sour bamboo shoots.
研究领域:
微生物学
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食品科学
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DOI
高影响因子
CyTA-Journal of Food
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2018
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IF 1.371
Liang Li,Ying Ma
Methyl ketones can be formed by the metabolism of intermediate products of β-oxidation by enzymes. In this article, the effect of soluble saccharides on the activity of key enzymes involved in methyl ketone synthesis in L. lactis was studied by detecting the relationship between soluble saccharides and enzyme activity. The results showed that glucose, fructose, sucrose, lactose and galactose could promote the growth of L. lactis. Glucose induced the activity of enoyl-coenzyme A (CoA) hydratase but inhibited the activity of β-hydroxyacyl-CoA dehydrogenase. Fructose induced the activities of acyl-CoA dehydrogenase and enoyl-CoA hydratase while maintaining the activity of β-hydroxyacyl-CoA dehydrogenase. Sucrose induced the activities of enoyl-CoA hydratase and β-hydroxyacyl-CoA dehydrogenase and maintained the activity of thiolase. Lactose also induced enoyl-CoA hydratase activity. Galactose induced enoyl-CoA hydratase activity and maintained thiolase activity. Glucose, lactose, fructose and galactose induced thioesterase activity. The data showed fructose and lactose could inhibit thiolase activity and induce thioesterase activity, which would be beneficial to methyl ketone synthesis, so fructose and lactose were the best soluble saccharides, followed by galactose, glucose and sucrose. A positive and significant correlation was found between thioesterase activity and enoyl-CoA hydratase activity (p < 0.01). In summary, the β-oxidation system of L. lactis is related to sugar metabolism.
研究领域:
微生物学
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生物化学
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DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Jianrui Qi,Jie Zhang,Kai Wang,Yifan Cheng,Qinglin Sheng,Ivan Kurtovic,Yahong Yuan,Tianli Yue
There is a lack of research on how Tibetan kefir grains fermentation alters the physicochemical properties and biological activity of Lycium barbarum pulp polysaccharides, despite some reports that fermentation can affect the structure and activity of plant polysaccharides. This study demonstrated that, through fermentation, the molecular weight of polysaccharides decreased from 25.33 to 15.11 kg/mol while the contents of total sugar and uronic acid increased by 19.11% and 40.38%, respectively. Furthermore, after fermentation, the polysaccharides exhibited an uneven and rough surface along with a reduced number of branched chains and triple helix structures. Tibetan kefir grains fermentation enhanced the antioxidant activity of polysaccharides, which may be attributed to an increase in arabinose, galactose, and uronic acid content and a decrease in polysaccharide molecular weight. This research offers an alternative viewpoint on the potential application of Tibetan kefir grains-fermented Lycium barbarum pulp polysaccharides in functional foods.
研究领域:
食品科学
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营养学
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生物技术
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产品关联
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
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2023
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IF 4.4
Yu-Chi Tseng,Chengfeng Xue,I-Son Ng
The abundance and biodiversity of intestinal bacteria play a critical role in immune system. Escherichia coli Nissle 1917 (EcN), a tractable probiotic cell has emerged as a ‘smart microbe’ that can provide therapeutic modalities at the sites of disease. Additionally, Lactobacillus rhamnosus GG (LGG) represents one of the key probiotics in clinical studies with the ability to enhance intestinal immunity in symbiosis with other cells. To fully exploit the advantages of EcN and LGG, we optimized the commensal culture medium for LGG and EcN, succeeded by the establishment of a novel fluorescence-based colony quantification. From the metabolite analysis, more lactate was consumed when LGG is co-cultured with EcN; thus, YkgG was further explored as it was foreseen to be the enzyme responsible for lactate conversion to pyruvate. The YkgG enzyme from EcN has V max of 64.5 mM min -1 and catalytic ability k cat /K m of 2055 mM -1 min -1 , that is 6-fold compared to E. coli MG1655. Co-culture strategy of EcN with LGG in the mimic gastrointestinal tract increased the CFU by 50 % and 40 % within 5 mins and 10 mins, respectively. This practical, feasible, and promising symbiosis system aims to accelerate the application of probiotic in healthy food industries.
研究领域:
微生物学
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免疫学
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食品科学
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产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2022
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IF 6.056
Yangrui Wang,Mengtong Sun,Xiaoling Cui,Yongyue Gao,Xinran Lv,Jianrong Li,Fengling Bai,Xuepeng Li,Defu Zhang,Kai Zhou
Vibrio harveyi is one of the main pathogenic bacteria in the aquaculture industry, and quorum sensing (QS) plays key role in its pathogenicity. Previous studies have demonstrated that a metabolite with protein properties isolated from Lactococcus lactis LY3-1 showed anti-QS activity against V. harveyi . In this study, this metabolite of L. lactis LY3-1 was identified as peptide LQLY3-1, with a 1.09 kDa molecular mass, which was purified via ethyl acetate extraction followed by ultrafiltration, Sephadex G25 gel chromatography, and high-performance liquid chromatography. Its amino acid sequence was ALSLVKIHGR, as demonstrated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Crude extracts of peptide LQLY3-1 at sub-minimum inhibitory concentrations inhibited V. harveyi biofilm formation and the production of virulence factors, including exopolysaccharide, proteolytic enzymes, hemolysin, gelatinase, and motility, albeit without inhibiting bacterial growth. Scanning electron microscopy images indicated that the crude extracts of peptide LQLY3-1 disrupted the integrity of the V. harveyi biofilm. Additionally, molecular docking analysis indicated that peptide LQLY3-1 could competitively bind to the LuxN receptor protein with its natural ligand N-octanoyl- l -homoserine lactone, thereby blocking the signal transmission of the QS system. These results suggested that peptide LQLY3-1 can be used as a promising QS inhibitor to control V. harveyi pathogenicity.
研究领域:
微生物学
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海洋生物学
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水产养殖
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Zhikun Yang,Chuang Li,Tao Wang,Zhihua Li,Xiaobo Zou,Xiaowei Huang,Xiaodong Zhai,Jiyong Shi,Tingting Shen,Yunyun Gong,Melvin Holmes,Megan Povey
A novel probiotic film based on gellan gum (GN), cranberry extract (CE), and Lactococcus lactis (LA) was developed in the present study. The fluorescence and SEM image results showed that GN/CE film containing LA was successfully fabricated. The incorporation of LA significantly enhanced the antibacterial activity of the film. The presence of CE strengthened the antioxidant activity and LA survivability in the film. The combination of LA (0–1.0 %) and CE (0.5–1.0 %) improved the mechanical property of the film through the formation of density structure. The best comprehensive properties were obtained with the film containing 2.0 %LA and 0.5 %CE. The GN/2.0 %LA/0.5 %CE film also showed the optimal preservation effect on fresh-cut potatoes and apples. Hence, GN/2.0 %LA/0.5 %CE probiotic film has proved to be suitable for fruit and vegetable preservation.
研究领域:
食品科学
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微生物学
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DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2024
·
IF 6
Yulong Zhang,Suo Zheng,Jingru Chen,Zhiliang Cheng,Fei Liu,Yuehua Jiao
Lactococcus lactis undergoing aerobic respiration can consume oxygen and form an anaerobic environment. Salmonella , as a facultative anaerobic foodborne pathogen, multiply better under aerobic conditions. The purpose of this study was to explore aerobic respiration of Lactococcus lactis subsp. lactis ( L. lactis ) KLDS 4.0325 inhibitory effect on Salmonella enterica subsp. enterica serovar Typhimurium ( S. Typhimurium) SL 1344 in vitro and its colonization ability in vivo . Results indicate that L. lactis KLDS 4.0325 could inhibit the growth of S. Typhimurium SL1344 by producing bacteriocin. And L. lactis KLDS 4.0325 undergoing aerobic respiration could enhance this inhibitory effect, while reducing the expression levels of virulence genes sipB , sipC , and sopE2 in S. Typhimurium SL1344. L. lactis KLDS 4.0325 could be successfully labeled by CFDA-SE fluorescent probe, and the labeling rate was more than 97%. Murine experiments showed that L. lactis KLDS 4.0325 could adhere and colonize in the cecum and colon. Thus, L. lactis KLDS 4.0325 is a promising probiotic strain for the potential inhibition of Salmonella infection via its oxygen-scavenging in host gut.
研究领域:
微生物学
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食品安全
·
分子生物学
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产品关联
DOI
高影响因子
FISH & SHELLFISH IMMUNOLOGY
·
2020
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IF 0
Chen Zhang,Sheng Guo,Zhao Zhao,Zi-Rao Guo,Rui Ma,Gao-Xue Wang,Bin Zhu
Spring viremia of carp virus (SVCV) causes devastating disease in aquaculture, resulting in significant economic impact. To develop an effective means against SVCV infection, a Lactococcus lactis ( L.lactis ) based subunit vaccine (pNZ-UGA) was developed based on surface displaying of SVCV glycoprotein using anchoring motif of the cA (C terminus of the peptidoglyvsn-binding) domains of AcmA, a major autolysin from L.lactis . The surface expression of SVCV glycoprotein was verified by indirect immunofluorescence assay. The efficacy of the constructed vaccine was further evaluated in common carp . The results showed that the higher levels of specific IgM could be detected in fish vaccinated with pNZ-UGA, compared with that in PBS and L.lactis groups. Immune-related genes including TNF-α , IL-6b , IL-1β , Cxcr 1 , Cxca , IFNg2b , I-IFN , and IgM expression in pNZ-UGA group were strongly up-regulated, revealing that robust innate immune response was induced. Notably, the lowest cumulative mortality (13.46%) was observed in fish vaccinated with pNZ-UGA vaccine after SVCV challenge, whereas the cumulative mortality were 100.00% and 92.31% in PBS and L.lactis groups, respectively. This study suggests the potential use of the recombinant L.lactis with surface displaying antigen proteins as effective vaccines against SVCV and other fish virus infection .
研究领域:
水产养殖
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病毒学
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免疫学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
Food Science and Human Wellness
·
2024
·
IF 5.6
Mengyang Liu,Xinping Lin,Jing Yang,Xu Yan,Chaofan Ji,Huipeng Liang,Sufang Zhang,Liang Dong
This study investigated the effects of salt (3 % and 6 %, m/m ) and rice flour (10 % and 20 %, m/m ) addition in sour meat, a traditional Chinese fermented meat. It was found that salt has greater effect than rice flour addition in spontaneous fermentation. Low-salt groups had lower pH and higher titratable total acid. In the low-salt groups, the dominant genera were Lactobacillus and Lactococcus , whereas Staphylococcus , Weissella , and Tetragenococcus were dominant in the high-salt groups. Higher total free amino acids and essential amino acids, organic acids, hexanoic acid ethyl ester and octanoic acid ethyl ester were found in the low-salt groups. The RDA analysis revealed that Lactococcus was closely related to product quality, with the S3F10 (3 % salt and 10 % rice flour) group outperforming the others in the sensory evaluation. Therefore, 3 % salt and 10 % rice flour were considered more appropriate for the production of healthy and tasty fermented sour meats.
研究领域:
食品科学
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微生物学
·
发酵技术
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DOI
高影响因子
Foods
·
2024
·Vol. 13
·期 19
·3054
·
IF 4.7
Jiacui Shang,Lijun Liu,Shuo Yang,Bofan Duan,Shuiqi Xie,Xiangchen Meng
Chronic inflammation is a factor in the development of cancer, and probiotics play a role in preventing or treating inflammation as an adjuvant therapy. To investigate potential probiotics for the prevention of colitis-associated colorectal cancer (CAC), Bifidobacterium bifidum H3-R2 and Lactococcus lactis KLDS4.0325 were used to examine the effects on colon cancer cells and in an inflammation-related cancer animal model. The results revealed that B. bifidum H3-R2 in combination with L. lactis KLDS4.0325 caused apoptosis in colon cancer cells by increasing caspase-3 and caspase-9 protein levels, enhancing Bax expression, and lowering Bcl-2 expression. In addition, the combination of the two strains relieved the tissue damage; reduced proinflammatory cytokines, myeloperoxidase (MPO) activity, and hypoxia-inducible factor 1-alpha (HIF-1α) level; upregulated anti-inflammatory cytokines; increased colonic tight junction protein expression; regulated intestinal homeostasis by inhibiting NLRP3 inflammasome signaling pathway; and improved the imbalance of gut microbiota in animal models. Moreover, the combination of the two strains had a greater preventive impact than each strain alone. These findings are supportive of clinical studies and product development of multi-strain probiotic preparations for diseases associated with colitis.
研究领域:
微生物学
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癌症研究
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胃肠病学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yuxue Zheng,Xingqian Ye,Yanyu Hu,Shaoyun Wang,Jinhu Tian
Recent studies show that starch-polyphenols complexes exert positive effects on gut health, but the probiotic effects of maize starch-caffeic complexes remain underexplored. Therefore, this study aimed to investigate the probiotic effect of maize starch–caffeic complexes from the small intestine to the colon. First, maize starch was extruded with caffeic acid and subjected to in vitro digestion, and the undigested parts were fermented in vitro , and the structural characteristics, short chain fatty acids (SCFAs) and microbiota communities were investigated. Results showed that caffeic acid reduced the long/short-range order of maize starch after extrusion, significantly increasing resistant starch to 30.35 ± 2.36 %. In vitro fermentation indicated that microbiota utilized the amorphous area of the residues first, promoting SCFAs production and the growth of Bifidobacterium and Lactococcus genus. Overall, the probiotic properties of extruded maize starch–caffeic acid complexes suggest they could serve as a functional food for health benefits.
研究领域:
食品科学
·
营养学
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胃肠病学
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微生物学
✓ 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）