• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.180-184
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• 2003

Several bacteria and yeasts were isolated from soil and characterized for the development of functional probiotics which can be used as a livestock feed additive. From the soil, the microbial strains which have acid/bovine resistance, antibiotics resistance and high stability, were isolated. Most strains selected were very tolerable against acids and very stable in a broad range of pH. Some strains could survive 100% at pH 2.5. The growth of the strains was not affected in the presence of bile acid, pathogenic E. coli and several antibiotics such as tetracycline, nisin, kanamycin, streptomycin, ampicillin. Acidogenic capability test showed that all the strains can produce acids. The hydrolytic activities were analysed for amylase, protease, lipase and cellulase to decompose various organic compounds. All the strains were found to be gram negative, round type, non-kinetic and the color is yellow or white.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.878-888
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• 2018

In the current study, the probiotic potential of approximately 250 strains of lactic acid bacteria (LAB) isolated from piglet fecal samples were investigated; among them Lactobacillus plantarum strain JDFM LP11, which possesses significant probiotic potential, with enhanced acid/bile tolerance, attachment to porcine intestinal epithelial cells (IPEC-J2), and antimicrobial activity. The genetic characteristics of strain JDFM LP11 were explored by performing whole genome sequencing (WGS) using a PacBio system. The circular draft genome have a total length of 3,206,883 bp and a total of 3,021 coding sequences were identified. Phylogenetically, three genes, possibly related to survival and metabolic activity in the porcine host, were identified. These genes encode p60, lichenan permease IIC component, and protein TsgA, which are a putative endopeptidase, a component of the phosphotransferase system (PTS), and a major facilitator in the gut environment, respectively. Our findings suggest that understanding the functional and genetic characteristics of L. plantarum strain JDFM LP11, with its candidate genes for gut health, could provide new opportunities and insights into applications in the animal food and feed additive industries.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.338-342
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• 2008

This study was performed to screen and select Lactobacillus strains from chicken feces for probiotic use in animals. Of these strains, strain AU had the highest immunostimulatory effect. Therefore, strain A12 was characterized as a potential probiotic. Strain A12 was tentatively identified as Lactobacillus acidophilus A12, using the API 50 CHL kit based on a 99.9% homology. L. acidophilus A12 was highly resistant to artificial gastric juice (pH 2.5) and bile acid (oxgall). Based on results from the API ZYM kit, leucine arylamidase, crystine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrolase, ${\alpha}$-galactosidase, ${\beta}$-galactosidase, ${\alpha}$-glucosidase, ${\beta}$-glucosidase, and N-acetyl-${\beta}$-glucosamidase were produced by strain A12. L. acidophilus A12 showed resistance to several antibiotics (nisin, gentamicin, and erythromycin). The amount of interleukin $(IL)-1{\alpha}$ in $20{\times}$ concentrated supernatant from L. acidophilus A12 was approximately 156pg/ml. With regard to antioxidant activity, L. acidophilus A12 supernatant showed 60.6% DPPH radical scavenging activity. These results demonstrate the potential use of L. acidophilus A12 as health-promoting probiotics.

• Journal of Microbiology and Biotechnology
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• v.29 no.11
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• pp.1729-1738
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• 2019

In sourdough fermentation, lactic acid bacteria perform important roles in the production of volatile and antimicrobial compounds, and exerting health-promoting effects. In this study, we report the probiotic properties and baking characteristics of Lactobacillus plantarum SPC-SNU 72-2 isolated from kimchi. This strain is safe to use in food fermentation as it does not carry genes for biogenic amine production (i.e., hdc, tdc, and ldc) and shows no β-hemolytic activity against red blood cells. The strain is also stable under simulated human gastrointestinal conditions, showing tolerance to gastric acid and bile salt, and adheres well to colonic epithelial cells. Additionally, this strain prevents pathogen growth and activates mouse peritoneal macrophages by inducing cytokines such as tumor necrosis factor-α, interleukin (IL)-6, and IL-12. Furthermore, the strain possesses good baking properties, providing rich aroma during dough fermentation and contributing to the enhancement of bread texture. Taken together, L. plantarum SPC-SNU 72-2 has the properties of a good starter strain based on the observation that it improves bread flavor and texture while also providing probiotic effects comparable with commercial strains.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.87-91
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• 1996

The optimum temperature and pH for the enzyme activity were 45$^{\circ}C$ and 10.0, respectively. The enzyme was stable in a pH range of 5 to 10, and 62% of its activity was lost on heat treatment of 60$^{\circ}C$ for 20 min. The activity of the purified enzyme was inhibited by $Fe^{2+},\;Zn^{2+}\;and\;Pb^{2+}$, and slightly activated by $Mn^{2+}\;and\;Ca^{2+}$. ${\gamma}$-Chloromercuribenzoic acid, 2,4-dinitrophenol and $H_{2}O_{2}$ did not show inhibitroy effect on the lipolytic activity of the alkaline lipase but ethylenediaminetetraacetic acid inhibited the enzyem activity. This suggested that the enzyme have metal group in its active site. Sodium salts of bile acids stimulated the enzyme activity. Analysis of hydrolyzates of olive oil after the reaction revealed that Serratia liquefaciens AL-11 produced non-specific lipolytic enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.396-401
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• 2012

To select potent probiotics from lactic acid bacteria in Yulmoo Kimchi, an in vitro and stimulated human intestinal model system (SHIMS) test were performed. One Leuconostoc mesenteroides strain from five strains of Yulmoo Kimchi and one Lactobacillus plantarum from 12 strains of KCTC and KCCM were selected according to survival in acidic and bile salts conditions. Between the two species, Leu. mesentroides displayed higher survival activity in a SHIMS test. The strain was identified as Leu. mesentroides by 16S rRNA sequencing and was designated as Leu. mesentroides K01.

• Nutritional Sciences
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• v.3 no.1
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• pp.25-30
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• 2000

To study the effect of prosomillet (Panicum milaceum) on lipid metabolism, male Sprague-Dawley rats weighing 190$\pm$8g were fed six experimental diets for four weeks. The six diets based on AIN-76 composition consisted of one cholesterol-free(normal) and five 1%(w/w) cholesterol diets, i.e. control, two diets containing additional 0.3 and 0.6%(w/w) methanol extracts of prosomillet and another two diets containing 15 and 30% (w/w) prosomillet powder. There was no difference in weight gains between the groups but relative liver weights increased under the cholestrol diets. Plasma levels of total cholesterol and triglyceride(TG) decreased by 23-27% and by 37-52%, respectively, in the four prosomillet diet groups compared to those of the normal and control groups. Whereas in the liver, only TG levels decreased in the prosomillet diet groups. Fecal excretions of bile acid and cholesterol significantly with methanol extracts of prosomillet. There was a significant increase in the activity of hepatic microsomal cholesterol 7$\alpha$-hydroxylase when feeding 1% cholesterol but prosomillet in the diet, either as in the form of powder or methanol extract, appeared to have only slight additional effects, namely increases in enzyme activity. The activity of liver cytosolic glucose-6-phophate dehydrogenase (G6PDH) tended to be reduced with high cholesterol diets and dropped markedly by 15% using additional prosomillet powder. Those of the liver cytoxolic malic enzyme had a similar tendency to those of G6PDH. The results indicate that certain active components in prosmillet other than fiber have the potential to exert hypolipidemic effects via regulating cholesterol excretions and lipogenesis.

• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.188-192
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• 1999

To study effects of methanol extract of prosomillet on lopid metabolism , five groups of male Sprang-Dawley rats weighing 116$\pm$9 g were fed test diets for four weeks. The five diets consisted of one low fat(5% w/w) diet containing starch as carbohydrate source(normal) and four high fat diets(15% w/w) containing 40.5%(w/w)sucrose(control) and additional 80% nethanol extractof prosomillet at the levels of 0.3% and 1%(w/w) or prosomillet powder at the level of 20%(w/w). Serum level of total cholesterol was a little higher but that of triglyceride was 41% lower in 20% (w/w) prosomillet powder group than in the control group. The cholesterol levels of two Liver cholesterol levels were lower and phospolipid levels higher in all three prosomillet powder group . Fecal excretionof bile acid was most increased in the prosomillet powder group among all five test groups. Acitivity of liver microsomal 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase was significantly lower in 0.3% methanol extract fed group than the control and also appeared to be reduced in 1% extract fed one, wherease those of 20 cholesterol 7$\alpha$-hydroxylase were not different among the five groups. Activities of liver cytosilic glucose-6-phosphate dehydrogenase(G6PDH) and malic enzyme were decreased in 0.3% prosomillet methanol extract and 20% powder groups. The results indicate that in addition to fiber, certain active components in prosomillet have potential to exert hypolipidemic effects via regulating hepatic cholesterogenesis and lipogenesis.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.967-982
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• 2021

Probiotics are living microorganisms that, when administered in adequate amounts, provide a health benefit to the host and are considered safe. Most probiotic strains that are beneficial to human health are included in the "Lactic acid bacteria" (LAB) group. The positive effects of probiotic bacteria on the host's health are species-specific and even strain-specific. Therefore, evaluating the probiotic potential of both wild and novel strains is essential. In this study, the probiotic characteristics of Lactobacillus brevis KT38-3 were determined. The strain identification was achieved by 16S rRNA sequencing. API-ZYM test kits were used to determine the enzymatic capacity of the strain. L. brevis KT38-3 was able to survive in conditions with a broad pH range (pH 2-7), range of bile salts (0.3%-1%) and conditions that simulated gastric juice and intestinal juice. The percentage of autoaggregation (59.4%), coaggregation with E. coli O157:H7 (37.4%) and hydrophobicity were determined to be 51.1%, 47.4%, and 52.7%, respectively. L. brevis KT38-3 produced β-galactosidase enzymes and was able ferment lactose. In addition, this strain was capable of producing antimicrobial peptides against the bacteria tested, including methicillin and/or vancomycin-resistant bacteria. The cell-free supernatants of the strain had high antioxidant activities (DPPH: 54.9% and ABTS: 48.7%). Therefore, considering these many essential in vitro probiotic properties, L. brevis KT38-3 has the potential to be used as a probiotic supplement. Supporting these findings with in vivo experiments to evaluate the potential health benefits will be the subject of our future work.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1144-1153
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• 2021

A released exopolysaccharide (rEPS)-producing strain (LM187) with good acid resistance, bile salt resistance, and cholesterol-lowering properties was isolated from Sichuan paocai and identified as Leuconostoc mesenteroides subsp. mesenteroides. The purified rEPS, designated as rEPS414, had a uniform molecular weight of 7.757 × 10⁵ Da. Analysis of the monosaccharide composition revealed that the molecule was mainly composed of glucose. The Fourier transform-infrared spectrum showed that rEPS414 contained both α-type and β-type glycosidic bonds. ¹H and ¹³C nuclear magnetic resonance spectra analysis showed that the purified rEPS contained arabinose, galactose, and rhamnose, but less uronic acid. Scanning electron microscopy demonstrated that the exopolysaccharide displayed a large number of scattered, fluffy, porous cellular network flake structures. In addition, rEPS414 exhibited strong in vitro antioxidant activity. These results showed that strain LM187 and its rEPS are promising probiotics with broad prospects in industry.