• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.2018-2026
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• 2007

A bacterium, Pseudomonas aeruginosa BM114, capable of accumulating a blend of medium-chain-length (MCL)- and short-chain-length (SCL)-polyhydroxyalkanoic acid (PHA), was isolated. Salicylic acid (SA), without being metabolized, was found to specifically inhibit only the accumulation of MCL-PHA without affecting cell growth. An addition of 20 mM SA selectively inhibited the accumulation of MCL-PHA in decanoate-grown cells by 83% of the control content in one-step cultivation, where overall PHA accumulation was inhibited by only ${\sim}11%$. Typically, the molar monomer-unit ratio of the PHA for 25 mM decanoate-grown cells changed from 46:4:25:25 (=[3-hydroxybutyrate]:[3-hydroxycaproate]: [3-hydroxyoctanoate]:[3-hydroxydecanoate]) at 0 mM SA (dry cell wt, 1.97 g/l; PHA content, 48.6 wt%) to 91:1:4:4 at 20 mM SA (dry cell wt, 1.85 g/l; PHA content, 43.2 wt%). Thus, the stimulation of SCL-PHA accumulation was observed. Growth of P. aeruginosa BM114 on undecanoic acid also produced a PHA blend composed of 47.4% P(3HB-co-3-hydroxyvalerate) and 52.6% P(3-hydroxyheptanoate-co-3-hydroxynonanoate-co-3-hydroxyundecanoate). Similar to the case of even-carboxylic acids, SA inhibited the accumulation of only MCL-PHA, but stimulated the accumulation of SCL-PHA. For all medium-chain fatty acids tested, SA induced a stimulation of SCL-PHA accumulation in the BM114 strain. SA could thus be used to suppress only the formation of MCL-PHA in Pseudomonas spp. accumulating a blend of SCL-PHA and MCL-PHA.

• Journal of Life Science
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• v.23 no.1
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• pp.143-156
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• 2013

Due to the high incidence of cancer and cancer-related mortality in Korea, there is increased concern and psychological anxiety about this disease, leading to increasing numbers of cancer studies. Despite these, the trend of the cancer incidence rate has shown a significant increase. The detection of colorectal cancer, which has a high incidence rate, often tends to be delayed, causing a high mortality rate. Therefore, the prevention of colorectal cancer has become an important emergent issue. The cause of this cancer has not been confirmed. However, it may be attributable to westernized dietary patterns, which include consuming a high quantity of red meat. Consumption of dietary fiber promotes the production of butyrate short-chain fatty acids by enteric bacteria. In the treatment of cancer, anticancer medications have been shown to lead to the apoptosis of tumor cells, and a strong relationship between apoptosis mechanisms of tumor cells and cancer treatment has been confirmed. The results of many studies have confirmed that butyrate can directly promote the apoptosis of colorectal cancer cells. Therefore, increased consumption of dietary fiber, which promotes the production of butyrate shortchain fatty acids, can be expected to have an effect on the prevention and treatment of colorectal cancer.

• Animal Bioscience
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• v.36 no.8
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• pp.1209-1220
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• 2023

Objective: The use of probiotics as an alternative to antibiotics in animal feed has received considerable attention in recent decades. Lactic acid bacteria (LAB) have remarkable functional properties promoting host health and are major microorganisms for probiotic purposes. The aim of this study was to characterize LAB strains of the chicken digestive tract and to determine their functional properties for further use as potential probiotics in poultry. Methods: A total of 2,000 colonies were isolated from the ileum and cecal contents of the chickens based on their phenotypic profiles and followed by a preliminary detection for acid and bile tolerance. The selected 200 LAB isolates with exhibited well-tolerance in acid and bile conditions were then identified by sequencing the 16S rDNA gene, followed by acid and bile tolerance, antimicrobial activity, adhesion to epithelial cells and additional characteristics on the removal of cholesterol. Then, the two probiotic strains (L. ingluviei and L. salivarious) which showed the greatest advantage in vitro testing were selected to assess their efficacy in broiler chickens. Results: It was found that 200 LAB isolates that complied with all measurement criteria belonged to five strains, including L. acidophilus (63 colonies), L. ingluviei (2 colonies), L. reuteri (58 colonies), L. salivarius (72 colonies), and L. saerimneri (5 colonies). We found that the L. ingluviei and L. salivarius can increase the population of LAB and Bifidobacterium spp. while reducing Enterobacteria spp. and Escherichia coli in the cecal content of chickens. Additionally, increased concentrations of valeric acid and short chain fatty acids were also observed. Conclusion: This study indicates that all five Lactobacillus strains isolated from gut contents of chickens are safe and possess probiotic properties, especially L. ingluviei and L. salivarius. Future studies should evaluate the potential for growth improvement in broilers.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.14 no.1
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• pp.59-77
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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 -cyclodextrin ($\beta$-CD): l) Control (no homogenization, no $\beta$-CD), and 2) Milk treatment (1000 psi milk homogenization, 1 % $\beta$-CD). The cholesterol removal of the cheese were 79.3%. The production of short-chain free fatty acids (FF A) increased with a ripening time in both control and milk treated cheese. The releasing quantity of short-chain FFA was higher din milk treated cheese than control at 5 and 7 mo ripening. Not much difference was found in neutral volatile compounds 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, however, that in cholesterol-reduced cheese decreased dramatically with ripening time.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.450-458
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• 2006

The present study was carried out to investigate the changes in chemical and sensory properties, and cholesterol lowering effect of evening primrose oil (EPO) addition in cholesterol-reduced Cheddar cheese. The cholesterol removal rate reached 92.07% by ${\beta}$-cyclodextrin in the cheese before EPO addition. The thiobarbituric acid (TBA) value of cholesterol-reduced and EPO-added cheese increased with both ripening time and amount of EPO addition. Addition of 5% EPO resulted in a significant difference in TBA value after 4-week ripening, compared with no addition of EPO. The production of short-chain free fatty acids (FFAs) increased with ripening period in all treatments. From 4 week of ripening, the amounts of short-chain FFA in 3 and 5% EPO-added groups were significantly higher than those in other groups. Among sensory characteristics, rancidity was mostly affected by EPO addition, however, the rancidity value of 1% EPO-added was not significantly different from that of EPO-free and cholesterol-reduced cheese. Also, Cheddar cheese flavor was not profoundly affected by 1% EPO addition in all ripening periods. Total blood cholesterol dramatically decreased from 184.0 to 137.1 mg/dL with 5% EPO-added and cholesterol-reduced cheese following 8 weeks of feeding. The present results indicated that 5% EPO addition resulted in a profound lowering effect on blood total cholesterol with some adverse effects on chemical and sensory properties.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1364-1373
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• 2012

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of $418{\pm}5$ kg and $36{\pm}10$ d in milk were randomly assigned according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g $Ca(OH)_2$ (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, $NH_3$-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DMI, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.60-64
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• 1985

To utilize microbial lipases for hydrolysis of milk fat, optimum reaction conditions and characteristics of enzymatic reactions of lipases originated from Rhizopus delemar, Mucor sp., and Candida cylindracea were investigated. Optimum pH and temperature were pH 5.6 and $45^{\circ}C$ for Rhizopus delemar lipase, pH7.5 and $35^{\circ}C$ for Mucor sp. lipase, and pH7.5 and $35^{\circ}C$ for Candida cylindracea lipase. Optimum lipase concentration and optimum substrate concentration were $600{\sim}800\;units/ml$ and 20% milk fat, regardless of their origin. Km values were 6.06% milk fat for Rhizopus delemar lipase, 7.69% for Mucor sp. lipase and 7.99% for Candida cylindracea lipase. Rate of lipid hydrolysis was Rhizopus delemar lipase>Mucor sp. lipase>Candida cylindracea lipase. As the reaction time was extended, liberation of short chain fatty acids was increased. After 8 hours reaction, capric acid content significantly increased with Candida cylindracea lipase, palmitic acid with Mucor sp. lipase and butyric acid with Rhizopus delemar lipase.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1657-1670
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• 2023

This study aimed to evaluate the effects of Limosilactobacillus fermentum and Lactiplantibacillus plantarum isolated from human feces coordinating with inulin on the composition of gut microbiota and metabolic profiles in db/db mice. These supplements were administered to db/db mice for 12 weeks. The results showed that the Lactobacillaceae coordinating with inulin group (LI) exhibited lower fasting blood glucose levels than the model control group (MC). Additionally, LI was found to enhance colon tissue and increase the levels of short-chain fatty acids. 16S rRNA sequencing revealed that the abundance of Corynebacterium and Proteus, which were significantly increased in the MC group compared with NC group, were significantly decreased by the treatment of LI that also restored the key genera of the Lachnospiraceae_NK4A136_group, Lachnoclostridium, Ruminococcus_gnavus_group, Desulfovibrio, and Lachnospiraceae_UCG-006. Untargeted metabolomics analysis showed that lotaustralin, 5-hydroxyindoleacetic acid, and 13(S)-HpODE were increased while L-phenylalanine and L-tryptophan were decreased in the MC group compared with the NC group. However, the intervention of LI reversed the levels of these metabolites in the intestine. Correlation analysis revealed that Lachnoclostridium and Ruminococcus_gnavus_group were negatively correlated with 5-hydroxyindoleacetic acid and 13(S)-HpODE, but positively correlated with L-tryptophan. 13(S)-HpODE was involved in the "linoleic acid metabolism". L-tryptophan and 5-hydroxyindoleacetic acid were involved in "tryptophan metabolism" and "serotonergic synapse". These findings suggest that LI may alleviate type 2 diabetes symptoms by modulating the abundance of Ruminococcus_gnavus_group and Lachnoclostridium to regulate the pathways of "linoleic acid metabolism", "serotonergic synapse", and" tryptophan metabolism". Our results provide new insights into prevention and treatment of type 2 diabetes.

• Journal of Nutrition and Health
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• v.35 no.9
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• pp.912-918
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• 2002

In nature, two different types of fructose polymers (fructan) are generally found in dietary fibers; these are the fructose homopolymers levan, which is of high molecular weight and is $\beta$-(2,6)-linked, and inulin, which is of low molecular weight and is $\beta$-(2,1)-linked. The effects of levan and inulin on the intestinal physiology of rats were compared. Sprague Dawley rats were fed one of three diets for 3 weeks: a control diet, a basal diet containing 7% of levan, and a basal diet containing 7% of inulin. Cecal enlargement, together with the lowering of cecal pH, occurred in rats fed on the levan and inulin diets (p < 0.05). The levan and inulin diets resulted in a two-fold increase in the amount of short-chain fatty acids in the cecum, when compared to the control diet. The number of total microbes and of lactic acid-producing bacteria in the feces were higher in rats fed the fructan diets than those in rats fed control diet (p < 0.05). The levan diet also significantly increased the cecal $\alpha$-galactosidase activity by 3.8-fold, when compared to the control diet, indicating that levan stimulated the growth of Bifidobacteria in the cecum. These results show that the intake of levan and inulin stimulated the growth of lactic acid-producing bacteria in the cecum and thereby improved intestinal conditions in rats. (Korean J Nutrition 35(9) : 912~918,2002)

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1791-1799
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• 2018

Weaning stress can affect the growth performance and intestinal health of piglets. Dietary alternatives to antibiotics, such as dietary probiotics, especially those containing multiple microbial species, are a preventive strategy for effectively controlling post-weaning diarrhea. In this study, we investigated forty-eight crossbred piglets in three treatment groups for 21 days: the control and experimental groups were supplemented with Enterococcus faecium DSM 7134, Bacillus subtilis AS1.836 plus Saccharomyces cerevisiae ATCC 28338 (EBS) or Lactobacillus paracasei L9 CGMCC No. 9800 (EBL). On day 21, weaned piglets supplemented with two kinds of probiotic complexes showed increased growth performance and significantly reduced post-weaning diarrhea (p < 0.05). The EBS treatment increased acetic acid and propionic acid in the feces (p < 0.05), and the EBL treatment increased fecal acetic acid, propionic acid, butyrate and valerate (p < 0.05). Moreover, the fecal microbiota of the piglets changed markedly in EBL treatment. The addition of EBS and EBL may have similar effects on the prevention of diarrhea by improving the intestinal morphology and regulating the microbiota during the weaning period.