• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1314-1321
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• 2024

Branched-chain hydroxy acids (BCHAs), produced by lactic acid bacteria, have recently been suggested as bioactive compounds contributing to the systemic metabolism and modulation of the gut microbiome. However, the relationship between BCHAs and gut microbiome remains unclear. In this study, we investigated the effects of BCHAs on the growth of seven different families in the gut microbiota. Based on in vitro screening, both 2-hydroxyisovaleric acid (HIVA) and 2-hydroxyisocaproic acid (HICA) stimulated the growth of Lactobacillaceae and Bifidobacteriaceae, with HIVA showing a significant growth promotion. Additionally, we observed not only the growth promotion of probiotic Lactobacillaceae strains but also growth inhibition of pathogenic B. fragilis in a dose-dependent manner. The production of HIVA and HICA varied depending on the family of the gut microbiota and was relatively high in case of Lactobacillaceae and Lachnosporaceae. Furthermore, HIVA and HICA production by each strain positively correlated with their growth variation. These results demonstrated gut microbiota-derived BCHAs as active metabolites that have bacterial growth modulatory effects. We suggest that BCHAs can be utilized as active metabolites, potentially contributing to the treatment of diseases associated with gut dysbiosis.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.501-509
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• 1997

In recent papers[Bull. Kor. Chem. Soc. 1996, 17, 735; ibid 1997, 18, 478] we reported results of molecular dynamics (MD) simulations for the thermodynamic, structural, and dynamic properties of liquid normal alkanes, from n-butane to n-heptadecane, using three different models. Two of the three classes of models are collapsed atomic models while the third class is an atomistically detailed model. In the present paper we present results of MD simulations for the corresponding properties of liquid branched-chain alkanes using the same models. The thermodynamic property reflects that the intermolecular interactions become weaker as the shape of the molecule tends to approach that of a sphere and the surface area decreases with branching. Not like observed in the straight-chain alkanes, the structural properties of model Ⅲ from the site-site radial distribution function, the distribution functions of the average end-to-end distance and the root-mean-squared radii of gyration are not much different from those of models Ⅰ and Ⅱ. The branching effect on the self diffusion of liquid alkanes is well predicted from our MD simulation results but not on the viscosity and thermal conductivity.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1590-1597
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• 2017

Objective: This study aims to identify the relationship between odd- and branched-chain fatty acids (OBCFAs) and microbial nucleic acid bases in the rumen, and to establish a model to accurately predict microbial protein flow by using OBCFA. Methods: To develop the regression equations, data on the rumen contents of individual cows were obtained from 2 feeding experiments. In the first experiment, 3 rumen-fistulated dry dairy cows arranged in a $3{\times}3$ Latin square were fed diets of differing forage to concentration ratios (F:C). The second experiment consisted of 9 lactating Holstein dairy cows of similar body weights at the same stage of pregnancy. For each lactation stage, 3 cows with similar milk production were selected. The rumen contents were sampled at 4 time points of every two hours after morning feeding 6 h, and then to analyse the concentrations of OBCFA and microbial nucleic acid bases in the rumen samples. Results: The ruminal bacteria nucleic acid bases were significantly influenced by feeding diets of differing forge to concentration ratios and lactation stages of dairy cows (p<0.05). The concentrations of OBCFAs, especially odd-chain fatty acids and C15:0 isomers, strongly correlated with the microbial nucleic acid bases in the rumen (p<0.05). The equations of ruminal microbial nucleic acid bases established by ruminal OBCFAs contents showed a good predictive capacity, as indicated by reasonably low standard errors and high R-squared values. Conclusion: This finding suggests that the rumen OBCFA composition could be used as an internal marker of rumen microbial matter.

• Polymer(Korea)
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• v.36 no.2
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• pp.245-250
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• 2012

Branched polypropylenes (PP) with long chain branch were prepared by solid state reaction with three different branching agent of 0.3 wt% content. The chemical structures, non-isothermal crystallization behavior and complex viscosity of the branched PP were investigated by FTIR, DSC, optical microscope, and dynamic rheological measurement. The chemical structure of the branched PP was confirmed by the existence of =C-H stretching peak of the branching agent at 3100 $cm^{-1}$. There was no distinct change in melting temperature in case of PP-D-0-3 and PP-F-0-3, but PP-H-0-3 indicated a decrease in melting temperature. The decrease in melting temperature was interpreted by the fact that the degradation reaction of PP was more dominant than branched reaction, and confirmed by a decrease in complex viscosity. The non-isothermal crystallization behavior of the branched PP was analyzed using by Avrami equation. The Avrami exponent of PP was 3, and the values of the branched PP with DVB and FS were below 3. The activation energy of PP calculated by Kissinger method was 25 kJ/mol, and there were no big difference in activation energies of the branched PPs compared to PP.

• Journal of Animal Science and Technology
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• v.64 no.4
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• pp.800-811
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• 2022

The integration of metabolomics and transcriptomics may elucidate the correlation between the genotypic and phenotypic patterns in organisms. In equine physiology, various metabolite levels vary during exercise, which may be correlated with a modified gene expression pattern of related genes. Integrated metabolomic and transcriptomic studies in horses have not been conducted to date. The objective of this study was to detect the effect of moderate exercise on the metabolomic and transcriptomic levels in horses. In this study, using nuclear magnetic resonance (NMR) spectroscopy, we analyzed the concentrations of metabolites in muscle and plasma; we also determined the gene expression patterns of branched chain (alpha) keto acid dehydrogenase kinase complex (BCKDK), which encodes the key regulatory enzymes in branched-chain amino acid (BCAA) catabolism, in two breeds of horses, Thoroughbred and Jeju, at different time intervals. The concentrations of metabolites in muscle and plasma were measured by ¹H NMR (nuclear magnetic resonance) spectroscopy, and the relative metabolite levels before and after exercise in the two samples were compared. Subsequently, multivariate data analysis based on the metabolic profiles was performed using orthogonal partial least square discriminant analysis (OPLS-DA), and variable important plots and t-test were used for basic statistical analysis. The stress-induced expression patterns of BCKDK genes in horse muscle-derived cells were examined using quantitative reverse transcription polymerase chain reaction (qPCR) to gain insight into the role of transcript in response to exercise stress. In this study, we found higher concentrations of aspartate, leucine, isoleucine, and lysine in the skeletal muscle of Jeju horses than in Thoroughbred horses. In plasma, compared with Jeju horses, Thoroughbred horses had higher levels of alanine and methionine before exercise; whereas post-exercise, lysine levels were increased. Gene expression analysis revealed a decreased expression level of BCKDK in the post-exercise period in Thoroughbred horses.

• BMB Reports
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• v.31 no.1
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• pp.37-43
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• 1998

The catabolic ${\alpha}$-acetolactate synthase was purified to homogeneity from Serratia marcescens ATCC 25419 using ammonium sulfate fractionation, DEAE-Sepharose, Phenyl-Sepharose, and Hydroxylapatite column chromatography. The native molecular weight of the enzyme was approximately 150 kDa and composed of two identical subunits with molecular weights of 64 kDa each. The N-terminal amino acid sequence of the enzyme was determined to be Ala-Gln-Glu-Lys-Thr-Gly-Asn-Asp-Trp-Gln-His-Gly-Ala-Asp-Leu-Val-Val-Lys-Asn-Leu. It was not inhibited by the branched chain amino acids and sulfometuron methyl herbicide. The optimum pH of the enzyme was around pH 5.5 and the pI value was 6.1. The catabolic ${\alpha}$-acetolactate synthase showed weak immunological relationships with recombinant tobacco ALS, barley ALS, and the valine-sensitive ALS isozyme from Serratia marcescens.

• Proceedings of the Korean Society of Rheology Conference
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• 2001.09a
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• pp.157.4-157
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• 2001

• Journal of Nutrition and Health
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• v.36 no.6
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• pp.577-588
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• 2003

Severe protein-calorie malnutrition, common in patients with advanced liver disease, can seriously undermine the capacity for regeneration and functional restoration of liver. Nutritional supplementation for these patients can improve biochemical and hormonal abnormalities. However, these effects were not identified in patient with nonalcoholic liver cirrhosis. To determine effects of nutritional supplementation in patients with nonalcoholic liver cirrhosis, 77 subjects aged 29 to 69 years participated in this study for 12 weeks and were subdivided into three groups; normal diet group (Control group, n ＝ 16), branched-chain amino acid supplementation group (BCAA group, n ＝ 31), nutritional supplementation group (NS group, n ＝ 30). Anthropometric parameters, hemoglobin, hematocrit, blood cell counts, serum levels of lipids, vitamins, minerals and fatty acid composition, and plasma amino acids were examined. The mean values of age and height, and the initial values of weight and body mass index (BMI) were not different among all groups. After 12 weeks, there were no significant changes in these values in Control group. Only NS group showed significant increases in weight, lean body mass, midarm circumference, triceps skinfold thickness. Serum transferrins were increased both in BCAA and NS groups. Plasma levels of branched-chain amino acids, urea amino acids and glutamic acid were also significantly increased in these groups, but plasma levels of ammonia, serum LDL cholesterol and atherogenic index were decreased. However, there were no significant changes in serum levels of vitamin and mineral and composition of fatty acids in phospholipids in these groups. These results showed that the nutritional supplementation for patients with nonalcoholic liver cirrhosis can more improve nutritional status in these people together with increases of weight, body fat and lean body mass, compared to only BCAA supplementation. To ascertain and investigate the appropriate nutritional supplementation for patients with nonalcoholic liver cirrhosis, further studies are necessary.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.106-113
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• 2010

In this study, we compared corn gluten hydrolyzates, BCAAs, and leucine for their effects on body weight reduction in high fat-induced obese rats in order to determine the major active components in the corn gluten hydrolyzates. After obesity was induced for 13 weeks with high fat diet, the overweight-induced SD rats (n = 64) were stratified according to body weight, randomly blocked into eight treatments, and raised for 8 weeks. Four groups were changed to a normal diet and the other groups remained on the high fat diet. Each of the groups within both diets was fed either casein, corn gluten hydrolyzates, leucine, or branched chain amino acids, respectively. Daily food intake, body weight gain, and food efficiency ratio were significantly lower in the corn gluten hydrolyzate groups compared to the other groups, regardless of the high fat diet or normal fat diet. The rats fed the corn gluten hydrolyzates diet had the lowest perirenal fat pad weights whereas muscle weight was significantly increased in the corn gluten hydrolyzates groups. Plasma triglyceride, hepatic total lipid, and total cholesterol contents were significantly reduced in the corn gluten hydrolyzates groups. Other lipid profile measurements were not significantly changed. Plasma triglyceride and hepatic total lipid were also significantly reduced in the BCAA and leucine groups. Leptin levels were significantly lower and adiponectin was significantly higher in the corn gluten hydrolyzates groups. Fasting blood glucose, insulin, C-peptide, and HOMA-IR levels were also significantly reduced in the corn gluten hydrozylates groups, regardless of fat level.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1495-1503
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• 2009

This experiment was conducted to determine the effect of dietary supplementation with BCAA (branched-chain amino acids: leucine, isoleucine and valine) on improving the growth of rats in a malnutritional IUGR (Intrauterine Growth Retardation) model, which was established by feeding restriction. In the experimental treatment, rats were fed purified diets supplemented with BCAA (mixed) during the whole gestation period, while arginine and alanine supplementation were set as the positive and negative control group, respectively. The results showed that, compared to the effect of alanine, BCAA reversed IUGR by increasing the fetus weights by 18.4% and placental weights by 18.0% while fetal numbers were statistically increased. Analysis of gene and protein expression revealed that BCAA treatment increased embryonic liver IGF-I expression; the uterus expressed higher levels of estrogen receptor-$\alpha$ (ER-$\alpha$) and progesterone receptor (PR), and the placenta expressed higher levels of IGF-II. Amino acid analysis of dam plasma revealed that BCAA supplementation effectively enhanced the plasma BCAA levels caused by the feed restriction. BCAA also enhanced the embryonic liver gluconeogenesis by augmenting the expression of two key enzymes, namely fructose-1,6-biphosphatase (FBP) and phosphoenolpyruvate carboxykinase (PEPCK). In conclusion, supplementation of BCAA increased litter size, embryonic weight and litter embryonic weight by improving the dam uterus and placental functions as well as increasing gluconeogenesis in the embryonic liver, which further provided energy to enhance the embryonic growth.