Publications by authors named "Haisu Shi 史海粟"

This study explores the potential of aerotolerant Bacteroides fragilis () strains as next-generation probiotics (NGPs), focusing on their adaptability in the gastrointestinal environment, safety profile, and probiotic functions. From 23 healthy infant fecal samples, we successfully isolated 56 beneficial strains. Notably, the SNBF-1 strain demonstrated superior cholesterol removal efficiency in HepG2 cells, outshining all other strains by achieving a remarkable reduction in cholesterol by 55.

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Article Synopsis
  • Pork backfat (PB) has high levels of saturated fatty acids (SFAs) but low levels of polyunsaturated fatty acids (PUFAs), presenting an opportunity for enhancement through microbial fermentation.
  • A co-culture of Mucor circinelloides and Lactiplantacillus plantarum successfully converted PB into fermented pork backfat (FPB) with significant increases in γ-linolenic acid (GLA) and linoleic acid (LA) levels during fermentation.
  • Techniques such as ultrasound and adjustments to oxygen and ventilation rates promoted deeper microbial growth within the PB, further improving PUFA levels in both surface and internal layers of the fat.
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  • - The study isolated and characterized two fractions of Bacillus subtilis extracellular polysaccharides (BSPS), named BSPS-1 and BSPS-2, which differ in their sugar composition and molecular weights.
  • - BSPS-1 showed higher antioxidant activity compared to BSPS-2, achieving a 93.55% clearance of ABTS• and demonstrating concentration-dependent effects.
  • - Both BSPS-1 and BSPS-2 significantly inhibited the proliferation of HepG2 cells, promoting apoptosis; the effects were also dose-dependent, with particular growth inhibition observed in different cell cycle phases.
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  • * Single-omics analysis helps identify key microbial factors affecting fermentation, but variations in processing and environment make it complex to fully understand these interactions.
  • * Recent advancements in multi-omics analysis provide a deeper insight into microbial communities, potentially leading to better control over fermentation processes and healthier products for consumers.
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Background: Mold-ripened cheeses have low levels of unsaturated fatty acids (UFAs). Geotrichum candidum is an adjunct culture for the development of Geotrichum-ripened cheese but has a low ability to produce high levels of UFAs. Δ12 fatty acid desaturase (FADS12) is a pivotal enzyme that converts oleic acid (OA) to linoleic acid (LA) and plays a vital role in UFA biosynthesis.

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Polyunsaturated fatty acids (PUFAs) have beneficial roles in a variety of human pathologies and disorders. Owing to the limited source of PUFAs in animals and plants, microorganisms, especially fungi, have become a new source of PUFAs. In fungi, fatty acid desaturases (F-FADS) are the main enzymes that convert saturated fatty acids (SFAs) into PUFAs.

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Horizontal gene transfer (HGT) has contributed significantly to the adaptability of bacteria, yeast and mold in fermented foods, whose evidence has been found in several fermented foods. Although not every HGT has biological significance, it plays an important role in improving the quality of fermented foods. In this review, how HGT facilitated microbial domestication and adaptive evolution in fermented foods was discussed.

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Major depressive disorder (MDD) is an enfeebling disease with a lifetime incidence of 20%. While accumulating studies implicate a correlation between the disease and gut microbiota, data show that not every patient responded to probiotic treatments. To comprehensively assess the potential role of probiotics in MDD, this study first summarizes the current pathological hypothesis of the disease from a life-stage perspective, focuses on the potential role of "depression gut microbiota.

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Exploring the synergistic effect of docosahexaenoic acid (DHA) or conjugated linoleic acid (CLA) with caffeic acid (CA) on ameliorating oxidative stress, thereby introducing CA to DHA or CLA will contribute significantly to enhance the bioactivity. We observed that DHA or CLA with CA promoted the recovery of intact individual morphology and the decline of cavities inside the nucleus and apoptosis under the observation of confocal laser scanning microscopy and fluorescent inverted microscope. The activity of intracellular antioxidant enzymes catalase (CAT) and glutathione peroxidase (GSH-Px), lactate dehydrogenase (LDH) leakage, pyruvate and malondialdehyde and reactive oxygen species (ROS), cellular morphology, and cell cycle were analyzed.

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Residual microorganisms in dairy products are closely related to their quality deterioration and safety. Based on the minimum sterilization conditions required by Grade A Pasteurized Milk Ordinance, this study explored the microbiota present in milk products that were high temperature short time pasteurized at 72, 75, 80, 83, or 85 °C for 15 s, 20 s, and 30 s separately. Based on high-throughput sequencing results, 6 phyla and 18 genera were identified as dominant microbiota.

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Cheese lacks essential fatty acids (EFAs). Delta 12 fatty acid desaturase (FADS12) is a critical enzyme required for EFA biosynthesis in fermentation of the predominant strains of cheese. Previously, we identified the FADS12 gene and characterized its function for the first time in Geotrichum candidum, a dominant strain used to manufacture soft cheese with white rind.

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Dajiang is a popular Chinese fermented soybean condiment. Here, a comparative metaproteomic analysis of traditional and commercial dajiang was performed during fermentation. A total of 4250 and 1421 peptide sequences were obtained from 3493 and 1987 proteins in traditional and commercial dajiang, respectively.

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Soft cheese with white rind lacks essential fatty acids (EFAs), and as a result its long-term consumption may lead to various kinds of cardiovascular and cerebrovascular diseases, such as hyperlipidemia, hypertension, and atherosclerosis. is a dimorphic yeast that plays an important role in the ripening of mold cheese. A gene coding for Δ12 fatty acid desaturase, a critical bifunctional enzyme desaturating oleic acid (OA) and linoleic acid (LA) to produce LA and α-linolenic acid (ALA), respectively, was isolated from , and then cloned and heterologously expressed in .

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Unlabelled: Dunaliella salina is a unicellular green alga with a high α-linolenic acid (ALA) level, but a low eicosapentaenoic acid (EPA) level. In a previous analysis of the catalytic activity of delta 6 fatty acid desaturase (FADS6) from various species, FADS6 from Thalassiosira pseudonana (TpFADS6), a marine diatom, showed the highest catalytic activity for ALA. In this study, to enhance EPA production in D.

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Delta 6 desaturase (FADS2) is a critical bifunctional enzyme required for PUFA biosynthesis. In some organisms, FADS2s have high substrate specificity, whereas in others, they have high catalytic activity. Previously, we analyzed the molecular mechanisms underlying high FADS2 substrate specificity; in this study, we assessed those underlying the high catalytic activity of FADS2s from and To understand the structural basis of this catalytic activity, GcFADS2 and TpFADS2 sequences were divided into nine sections, and a domain-swapping approach was applied to examine the role of each section in facilitating the catalytic activity of the overall protein.

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Background: Delta-6 desaturase (FADS6) is a key bifunctional enzyme desaturating linoleic acid (LA) or α-linolenic acid (ALA) in the biosynthesis of polyunsaturated fatty acids (PUFAs). In previous work, we analyzed the substrate specificity of two FADS6 enzymes from Mortierella alpina ATCC 32222 (MaFADS6) and Micromonas pusilla CCMP1545 (MpFADS6), which showed preference for LA and ALA, respectively. We also clarified the PUFA profiles in M.

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The ω6 and ω3 pathways are two major pathways in the biosynthesis of PUFAs. In both of these, delta 6 desaturase (FADS6) is a key bifunctional enzyme desaturating linoleic acid or α-linolenic acid. Microbial species have different propensity for accumulating ω6- or ω3-series PUFAs, which may be determined by the substrate preference of FADS6 enzyme.

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