• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.37-40
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• 1999

cDNAs for long- and short-chain acyl-CoA oxidases in fatty acid $\beta$-oxidation were isolated and were characterized their enzymatical and molecular properties. Both oxidases were exclusively localized in glyoxysomes, indicating that glyoxysomes can completely metabolize fatty acids to acyl-CoA by their cooperative action. In order to clarify the regulatory mechanisms underlying degradation of storage oil, we tried to obtain glyoxysome-deficient mutants of Arabidopsis. We screened 2,4-dichlorophenoxybutyric acid (2,4-DB) mutants of Arabidopsis which have defects in glyoxysomal fatty acid $\beta$-oxidation. Four mutants can be classified as carrying alleles at three independent loci, which we designated pedl, ped2, and ped3, respectively (where ped stands for peroxisome defective). The characteristics of these ped mutants are described.

• Animal Bioscience
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• v.35 no.10
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• pp.1461-1478
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• 2022

The maintenance of poultry gut health is complex depending on the intricate balance among diet, the commensal microbiota, and the mucosa, including the gut epithelium and the superimposing mucus layer. Changes in microflora composition and abundance can confer beneficial or detrimental effects on fowl. Antibiotics have devastating impacts on altering the landscape of gut microbiota, which further leads to antibiotic resistance or spread the pathogenic populations. By eliciting the landscape of gut microbiota, strategies should be made to break down the regulatory signals of pathogenic bacteria. The optional strategy of conferring dietary fibers (DFs) can be used to counterbalance the gut microbiota. DFs are the non-starch carbohydrates indigestible by host endogenous enzymes but can be fermented by symbiotic microbiota to produce short-chain fatty acids (SCFAs). This is one of the primary modes through which the gut microbiota interacts and communicate with the host. The majority of SCFAs are produced in the large intestine (particularly in the caecum), where they are taken up by the enterocytes or transported through portal vein circulation into the bloodstream. Recent shreds of evidence have elucidated that SCFAs affect the gut and modulate the tissues and organs either by activating G-protein-coupled receptors or affecting epigenetic modifications in the genome through inducing histone acetylase activities and inhibiting histone deacetylases. Thus, in this way, SCFAs vastly influence poultry health by promoting energy regulation, mucosal integrity, immune homeostasis, and immune maturation. In this review article, we will focus on DFs, which directly interact with gut microbes and lead to the production of SCFAs. Further, we will discuss the current molecular mechanisms of how SCFAs are generated, transported, and modulated the pro-and anti-inflammatory immune responses against pathogens and host physiology and gut health.

• BMB Reports
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• v.47 no.3
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• pp.173-178
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• 2014

There is rapidly growing interest in the human microbiome because of its implication in metabolic disorders and inflammatory diseases. Consequently, understanding the biology of short chain fatty acids and their receptors has become very important for identifying novel therapeutic avenues. GPR41 and GPR43 have been recognized as the cognate receptors for SCFAs and their roles in metabolism and inflammation have drawn much attention in recent years. GPR43 is highly expressed on immune cells and has been suggested to play a role in inflammatory diseases such as inflammatory bowel disease. Both GPR41 and GPR43 have been implicated in diabetes and obesity via the regulation of adipose tissue and gastrointestinal hormones. So far, many studies have provided contradictory results, and therefore further research is required to validate these receptors as drug targets. We will also discuss the synthetic modulators of GPR41 and GPR43 that are critical to understanding the functions of these receptors.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.409-416
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• 2003

This study was carried out to find a cholesterol removal rate, flavor development and bitter amino acid productions in Cheddar cheese treated with $\beta$-cyclodextrin (CD): 1) Control (no homogenization, no $\beta$-CD), and 2) Milk treatment (1000 psi milk homogenization, 1% $\beta$-CD). The cholesterol removal of the cheese was 79.3%. The production of short-chain free fatty acids (FFA) increased with a ripening time in both control and milk treated cheese. The releasing quantity of short-chain FFA was higher in milk treated cheese than control at 5 and 7 mo ripening. Not much difference was found in neutral volatile compound production between samples. In bitter-tasted amino acids, milk treatment group produced much higher than control. In sensory analysis, texture score of control Cheddar cheese significantly increased with ripening time, however, that in cholesterol-reduced cheese decreased dramatically. Our results indicated that the cheese made by $\beta$-CD treated milk with low pressure homogenization showed an effective cholesterol reduction and a rapid cheese ripening, while no capture of flavor compounds by $\beta$-CD.

• Food Science of Animal Resources
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• v.34 no.4
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• pp.543-551
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• 2014

The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products.

• Proceedings of the Botanical Society of Korea Conference
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• 1985.08b
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• pp.83-96
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• 1985

cDNAs for long- and short-chain acyl-CoA oxidases in fatty acid $\beta$-oxidation were isolated and were characterized their enzymatical and molecular properties. Both oxidases were exclusively localized in glyoxysomes, indicating that glyoxysomes can completely metabolize fatty acids to acyl-CoA by their cooperative action. In order to clarify the regulatory mechanisms underlying degradation of storage oil, we tried to obtain glyoxysome-deficient mutants of Arabidopsis. We screened 2,4-dichlorophenoxybutyric acid (2,4-DB) mutants of Arabidopsis which have defects in glyoxysomal fatty acid $\beta$-oxidation. Four mutants can be classified as carrying alleles at three independent loci, which we designated pedl, ped2, and ped3, respectively (where ped stands for peroxisome defective). The characteristics of these ped mutants are described.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1362-1370
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• 2015

This study was performed to investigate the effect of different levels of dietary crude protein (CP) on composition of odorous compounds and bacterial communities in pig manure. A total of 48 male pigs (average initial body weight 45 kg) fed diets containing three levels of dietary CP (20%, 17.5%, and 15%) and their slurry samples were collected from the pits under the floor every week for one month. Changes in composition of odorous compounds and bacterial communities were analyzed by gas chromatography and 454 FLX titanium pyrosequencing systems, respectively. Levels of phenols, indoles, short chain fatty acid and branched chain fatty acid were lowest (p<0.05) in CP 15% group among three CP levels. Relative abundance of Bacteroidetes phylum and bacterial genera including Leuconostoc, Bacillus, Atopostipes, Peptonphilus, Ruminococcaceae_uc, Bacteroides, and Pseudomonas was lower (p<0.05) in CP 15% than in CP 20% group. There was a positive correlation (p<0.05) between odorous compounds and bacterial genera: phenol, indole, iso-butyric acid, and iso-valeric acid with Atopostipes, p-cresol and skatole with Bacteroides, acetic acid and butyric acid with AM982595_g of Porphyromonadaceae family, and propionic acid with Tissierella. Taken together, administration of 15% CP showed less production of odorous compounds than 20% CP group and this result might be associated with the changes in bacterial communities especially whose roles in protein metabolism.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.540-542
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• 1998

Five microorganisms capable of degrading an aromatic medium-chain-length polyhydroxyalkanoate ($PHA_{MCL}$), poly(3-hydroxy-5-phenylvalerate) (PHPV), were isolated from wastewater-treatment sludge. Among the isolates, JS02 showed degrading activity consistantly during several transfers. The isolate JS02 could hydrolyze another aromatic MCL copolyester, poly(3-hydroxy-5-phenoxyvalerate-co-3-hydroxy-7-phenoxyheptanoate), ［P(5POHV-co-7POHH)］, and other short-chain-length PHAs ($PHA_{SCL}) such as poly(3-hydroxybutyrate) ［P3(HB)］, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) ［P(3 HB-co-4 HB)］, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) ［P(3HB-co-3HV)］ with relatively low activity. The culture supernatant of JS02 showed hydrolyzing activity for the p-nitrophenyl esters of fatty acids.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.389-396
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• 2016

This study examined the improving effect of DFA IV obtained from bacterial fermentation on the gut health. The effects of the dietary DFA IV on the intestinal mass, short chain fatty acids production and pH were evaluated in vivo. Sprague-Dawley rats were fed the 0% (control) or 1% DFA IV supplemented diets for 3 weeks. Supplementation of DFA IV resulted in a significant increase in cecal tissue and wall weights. Together with the lowering of the cecal and colonic pH, the amount of acetate and butyrate increased by 1.6 and 3.2 fold of the control group in the cecum, respectively, in the rats fed DFA IV diets. The DFA IV diet also significantly increased the cecal lactate 1.5 fold compared to the control diet, indicating that dietary DFA IV stimulated the growth of lactic acid bacteria and bifidobacteria in the intestine. Based on the above results, it is concluded that the dietary DFA IV may be used as a putative prebiotic supplement.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.10
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• pp.1456-1463
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• 2017

Objective: To investigate the effect of host genetics on gut microbial diversity, we performed a structural survey of the fecal microbiota of four purebred boar pig lines: Duroc, Landrace, Hampshire, and Yorkshire. Methods: The V3-V4 regions of the 16S rRNA genes were amplified and sequenced. Results: A total of 783 operational taxonomic units were shared by all breeds, whereas others were breed-specific. Firmicutes and Bacteroidetes dominated the majority of the fecal microbiota; Clostridia, Bacilli, and Bacteroidia were the major classes. Nine predominant genera were observed in all breeds and eight of them can produce short-chain fatty acids. Some bacteria can secrete cellulase to aid fiber digestion by the host. Butyric, isobutyric, valeric, and isovaleric acid levels were highest in Landrace pigs, whereas acetic and propionic acid were highest in the Hampshire breed. Heatmap was used to revealed breed-specific bacteria. Principal coordinate analysis of fecal bacteria revealed that the Landrace and Yorkshire breeds had high similarity and were clearly separated from the Duroc and Hampshire breeds. Conclusion: Overall, this study is the first time to compare the fecal microbiomes of four breeds of boar pig by high-throughput sequencing and to use Spearman's rank correlation to analyze competition and cooperation among the core bacteria.