Food Bioscience
·
2025
·
IF 5.9
Chun-lei Lu,Hua-xiang Li,Fedrick C. Mgomi,Zhen-quan Yang
Probiotic stability and activity during broth fermentation are crucial for enhancing the flavour and nutritional value of the final product. This study introduces a novel staining technique that allows differentiation of Lacticaseibacillus rhamnosus and Staphylococcus xylosus within sodium alginate (SA) encapsulated microspheres without altering the SA structure. Encapsulation efficiencies were 88.41% for L. rhamnosus and 82.68% for S. xylosus , with the staining technique enhancing thermal stability. Co-fermentation in pork broth resulted in significant increases in organic acids (e.g., lactic acid from 3.209 g/L to 8.673 g/L and acetic acid), thereby improving sensory attributes. Amino acid analysis revealed substantial increases in essential amino acids, including glutamic acid (from 7.493 mg/100 g to 27.422 mg/100 g) and glycine (from 12.435 mg/100 g to 30.632 mg/100 g), which contributed to an improved nutritional profile. Furthermore, significant increases in volatile compounds, such as isophorone (up to 148.25 μg/L), 1-Octanol (up to 39.02 μg/L), and benzaldehyde (up to 570.84 μg/L), enriched the aroma of the pork broth. SA encapsulation maintained probiotic viability throughout the extended fermentation period, while strain interactions further enriched both nutritional and flavour profiles. These findings highlight the potential of SA encapsulation combined with co-fermentation to optimize the sensory and nutritional qualities of fermented foods.
研究领域:
食品科学
·
微生物学
·
发酵工程
✓ 已验证
产品关联
DOI
高影响因子
Current Research in Food Science
·
2024
·
IF 6.2
Yuyang Li,Weiwei Chen,Jinxin Ma,Guoying Huang,Guangquan Li,Qiumei He,Xiangyu Kong,Ling Tang,Jinqing Chen,Wenyou Ding,Zhongbin Zhang,Wenya Ding
Currently, dairy mastitis caused by Staphylococcus xylosus poses a serious challenge for dairy farming. In this study, we explored the role and mechanism of rhein against S. xylosus with the hope of providing new research ideas to solve mastitis in dairy cows and ensure the source safety of dairy products. Through in vitro antimicrobial studies, we found that the minimum inhibitory concentration (MIC) of rhein was 64 μg/mL, and it significantly interfered with the formation of S. xylosus biofilm at sub-MIC. In experiments on mastitis in mice, rhein alleviated inflammation in mammary tissue, reduced the levels of TNF-α and IL-6, and decreased the number of S. xylosus . To explore the anti- S. xylosus mechanism of rhein, we identified the relevant proteins involved in carbon metabolism (Glycolysis/gluconeogenesis, TCA cycle, Fatty acid degradation) through proteomics. Additionally, proteins associated with the respiratory chain, oxidative stress (proteins of antioxidant and DNA repair), and nitrate respiration were also found to be upregulated. Thus, rhein may act as an antibacterial agent by interfering with the respiratory metabolism of S. xylosus and inducing the production of ROS, high levels of which alter the permeability of bacterial cell membranes and cause damage to them. We measured the concentrations of extracellular β-galactosidase and nucleic acids. Additionally, SEM observation of S. xylosus morphology showed elevated membrane permeability and damage to the cell membrane. Finally, RT-PCR experiments showed that mRNAs of key proteins of the TCA cycle (odhA, mqo) and nitrate respiration (nreB, nreC, narG) were significantly up-regulated, consistent with proteomic results. In conclusion, rhein has good anti- S. xylosus effects in vitro and in vivo, by interfering with bacterial energy metabolism, inducing ROS production, and causing cell membrane and DNA damage, which may be one of the important mechanisms of its antimicrobial activity.
研究领域:
微生物学
·
药理学
·
兽医学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Quality and Safety
·
2023
·
IF 5.6
Xu Zhiqiang,Zheng Wenbin,Zhao Shang,Chen Yong,Yang Qingli,Zhu Yinglian
In this paper, the effect of different concentrations of sucrose stress on color formation of the Staphylococcus xylosus was investigated. The results showed that the highest a* value and the best coloring effect similar to those of nitrite were observed after the addition of 0.05 g/mL sucrose to stress the S. xylosus. UV-Vis and electron spin resonance spectra analysis showed that production of coloring product Mb-NO was significantly enhanced after 0.05 g/mL sucrose stress. The growth curve, reactive oxygen content, cell cycle, nitric oxide synthase (NOS) activity, zeta potential, cell size, and protein composition of S. xylosus were investigated to reveal the mechanism of sucrose stress to enhance the coloring effect of the strain. The result showed that sucrose inhibited the growth of S. xylosus, which changed the physiological state by activating the oxidative stress response. The stress altered the rate of intracellular metabolism of S. xylosus by delaying the cell cycle and increasing cell surface zeta potential and cell particle size. These changes altered the protein composition of the cells and significantly enhanced the activity of intracellular NOS, which could improve the chromogenic ability of S. xylosus. This study will provide theoretical support for sucrose stress on S. xylosus to enhance its coloring effect, and sucrose stress for S. xylosus might be a promising biological alternative to nitrite in meat products.
研究领域:
食品科学
·
微生物学
·
生物化学
✓ 已验证
DOI
高影响因子