• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.608-619
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• 1998

The small and the large intestine of swine represent the organs that extract nutrients from feedstuffs through digestion and fermentation and that allow their absorption and incorporation into the blood circulation. Special attention is directed towards the small intestine of young pigs since the transition to a solid diet at weaning exerts major impacts on the structural and functional integrity of the small intestine. Dietary factors involved in postweaning changes of gut morphology and biochemistry such as removal of bioactive compounds in sows milk at weaning, anti-nutritional factors in weaner diets, dietary fiber and the role of voluntary feed intake will be elucidated. The microbial function of the large intestine which is carried out by a diverse population of microorganisms is dependent on substrate availability. Short chain fatty acids as main fermentation products contribute to the energy supply of the host but they are also important for the maintenance of the morphological and functional integrity of the epithelium in the colon. As a result of bacterial nitrogen assimilation in the large intestine, nitrogen is shifted from the urinary to the fecal excretion route thus saving metabolic energy to the pig because less ammonia would become available for conversion to urea.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2024-2033
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• 2015

A gene encoding lipolytic enzyme, lip7-3, was isolated from Bacillus sp. W130-35 isolated from a tidal mud flat. The gene encoded a protein of 215 amino acids with a signal peptide composed of 34 amino acid residues. Lip7-3 belonged to the family I.4 lipase and showed its maximal activity at pH 9.0 and 60℃. Its activity increased in the presence of 30% methanol and, remarkably, increased as well to 154.6% in the presence of Ca²⁺. Lip7-3 preferred p-nitrophenyl octanoate (C8) as a substrate and exhibited broad specificity for short- to long- chain fatty acid esters. Additionally, Lip7-3 showed a low degree of enantioselectivity for an S-enantiomer (e.g., (S)-methyl-3-hydroxy-2-methylpropionate). It efficiently hydrolyzed glyceryl tributyrate, but did not hydrolyze glyceryl trioleate, fish oil, or olive oil. Its substrate specificity and activation by the solvent might offer a merit to the biotechnological enzyme applications like transesterification in the production of biodiesel.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.342-350
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• 2017

The present study examined the physical, chemical, microbial, and sensory characteristics of Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts (0.5-2.0%) during storage at $7^{\circ}C$ for 60 d. The lactic acid bacterial count and lycopene concentrations in Queso Blanco cheese supplemented with powdered microcapsules were significantly higher than those of the control. In a texture analysis, the gumminess, chewiness, and hardness values for Queso Blanco cheese were significantly higher with increasing concentrations of the powdered microcapsules containing tomato extracts. Total short-chain fatty acids in Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts were not significantly altered compared to the control. Sensory evaluation scores for the yellowness, tomato taste, and firmness of Queso Blanco cheese were significantly higher after supplementation with powdered microcapsules containing tomato extracts.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.1
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• pp.117-123
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• 2002

This study was carried out to find the difference in flavor compounds between cholesterol-reduced Cheddar cheese slurries and control sample. The cheeses were made by 3 different treatments as followings: 1) Control (no homogenization, no ${\beta}$-CD), 2) Trt A (1,000 psi milk homogenization, 1% ${\beta}$-CD) and 3) Trt B (cream separation following by 10% ${\beta}$-CD, mixed with skim milk at 1,000 psi homogenization). The cholesterol removals of the cheeses were 79.30% (Trt A) and 91.22% (Trt B). The cheese slurries made by the cheeses were aged at $32^{\circ}C$ for 3 wk. The production of short-chain fatty acids (SCFA) was significantly increased with storage time in all treatments. Total amount of SCFA was dramatically increased at 2 wk and maintained thereafter in control group. The amounts of acetone and acetaldehyde were slightly increased in control at 3 wk, however, no difference was found in others. Ethanol production was dramatically increased at 1 wk and decreased thereafter in all treatments. Based on our results, cheese slurries for Trt B showed a highest cholesterol removal rate. Although little difference was found in flavor production, lower amount of SCFA was found in Trts A and B in 2 and 3 wk. It may indicate that a certain amount of SCFA is decreased during ${\beta}$-CD treatment.

• IMMUNE NETWORK
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• v.15 no.1
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• pp.44-49
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• 2015

Interactions between microbes and epithelial cells in the gastrointestinal tract are closely associated with regulation of intestinal mucosal immune responses. Recent studies have highlighted the modulation of mucosal immunity by microbe-derived molecules such as ATP and short-chain fatty acids. In this study, we undertook to characterize the expression of the ATP-gated $P2X_7$ receptor ($P2X_7R$) on M cells and its role in gastrointestinal mucosal immune regulation because it was poorly characterized in Peyer's patches, although purinergic signaling via $P2X_7R$ and luminal ATP have been considered to play an important role in the gastrointestinal tract. Here, we present the first report on the expression of $P2X_7R$ on M cells and characterize the role of $P2X_7R$ in immune enhancement by ATP or LL-37.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.49-55
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• 2021

The diet plays a fundamental role in the formation of the gut microbiota, determining the interrelationship between the gut microbiota and the host. The current study investigated the effect of Chlorella vulgaris on the gut microbiota by using simulated in vitro digestion and colonic fermentation. Bioaccessibility was measured after in vitro digestion, and SCFAs and microbial profiling were analyzed after colonic fermentation. The bioaccessibility of C. vulgaris was 0.24 g/g. The three major SCFAs (acetate, propionate, and butyrate) increased significantly when compared to the control group. In microbial profiling analysis, microorganisms such as Faecalibacterium, Dialister, Megasphaera, Dorea, Odoribacter, Roseburia, Bifidobacterium, Butyricmonas, and Veillonella were high in C. vulgaris group. Among them, Faecalibacterium, Dialister, Megasphaera, Roseburia, and Veillonella were thought to be closely associated with the increased level of SCFAs. Finally, it can be expected to help improve gut microbiota and health through ingestion of C. vulgaris. However, further studies are vital to confirm the changes in the gut microbiota in in vivo, when C. vulgaris is ingested.

• Journal of Microbiology and Biotechnology
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• v.31 no.11
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• pp.1568-1575
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• 2021

Obesity and related metabolic diseases are major problems worldwide. Some probiotics are currently considered potential therapeutic strategies for obesity. We aimed to investigate the anti-obesity efficacy of Latilactobacillus sakei WIKIM31 in obese mice induced by a high fat diet. The administration of a high-fat diet with L. sakei WIKIM31 reduced body weight gain, epididymal fat mass, triglyceride and total cholesterol levels in the blood, and remarkably decreased the expression of lipogenesis-related genes in the epididymal adipose tissue and liver. Interestingly, intake of L. sakei WIKIM31 improved gut barrier function by increasing the gene expression of tight junction proteins and suppressing the inflammatory responses. Additionally, L. sakei WIKIM31 enhanced the production of short-chain fatty acids, such as butyrate and propionate, in the intestinal tract. These results showed that L. sakei WIKIM31 can be used as a potential therapeutic probiotic for obesity.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.465-476
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• 2022

The importance of beneficial microorganisms, particularly probiotics, that coexist in the human body, is being increasingly recognized. Probiotics are representative health functional foods that provide health benefits to humans through the production of various metabolites, including short-chain fatty acids. However, the health benefits are strain-specific, and the use of each probiotic strain should follow guidelines that assure its safety. Accurate identification of the strain should be managed through genetic and phenotypic analyses of the strain. Besides, the functionality of probiotics should be disclosed in vitro and in vivo so that they can be used as legal functional ingredients (i.e., individual standards). In this review, we deal with the guidelines, including the technical factors related to probiotic strains. The common health effects of probiotic strains include proliferation of beneficial bacteria, control of harmful bacteria, and facilitation of bowel activities. Probiotics with various functionalities (e.g., body fat and cholesterol reduction, vaginal health, and improvement of skin's immune system) have been investigated as "individual standards of raw materials for health functional foods" provided by MFDS. In the future, various biotechnologies including synthetic biology can be applied to produce customized probiotics to improve human health.

• Journal of Applied Biological Chemistry
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• v.65 no.1
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• pp.63-74
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• 2022

Microbial dysbiosis in the gut is associated with human diseases, and variations in mucus alter gut microbiota. Therefore, we explored the effects of mucin on the gut microbiota using a community of 19 synthetic gut microbial species. Cultivation of these species in modified Gifu anaerobic medium (GAM) supplemented with mucin before synthetic community assembly facilitated substantial growth of the Bacteroides, Akkermansia, and Clostridium genera. The results of 16S rRNA microbial relative abundance profiling revealed more of the beneficial microbes Collinsella, Bifidobacterium, Ruminococcus, and Lactobacillus. This increased acetate levels in the community cultivated with, rather than without (control), mucin. We identified differences in predicted cell function and metabolism between microbes cultivated in GAM with and without mucin. Mucin not only changed the composition of the gut microbial community, but also modulated metabolic functions, indicating that it could help to modulate microbial changes associated with human diseases.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.823-830
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• 2023

Lactococcus lactis is a lactic acid bacterium and used in the dairy food industry. The ameliorating effects of Lactobacillus species on atopic dermatitis (AD) have been extensively studied, but the specific effect of L. lactis strains has not yet been investigated. In this study, the efficacy of L. lactis LB 1022, isolated from natural cheese, was evaluated using RAW 264.7, HMC-1 and HaCaT cell lines and an ovalbumin-sensitized AD mouse model. L. lactis LB 1022 exhibited nitric oxide suppression and anti-allergy and anti-inflammatory activity in vitro. Oral administration of L. lactis LB 1022 to AD mice significantly reduced the levels of IgE, mast cells, and eosinophils, and a range of T cell-mediated T helper Th1, Th2, and Th17-type cytokines under interleukin (IL)-10, transforming growth factor-β (TGF-β), thymus and activation-regulated chemokine (TARC), and thymic stromal lymphopoietin (TSLP). In addition, L. lactis LB 1022 treatment increased the concentration of short-chain fatty acids. Overall, L. lactis LB 1022 significantly modulated AD-like symptoms by altering metabolites and the immune response, illustrating its potential as candidate for use in functional food supplements to alleviate AD.