• Journal of Life Science
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• v.22 no.5
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• pp.642-649
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• 2012

The southern coast of Korea is important for the ark shell ($Scapharca$ $broughtonii$) aquaculture, but the productivity was rapidly reduced during the previous decade by mass mortality. To overcome this economic loss, investigations only focused on environmental factors, and microbiological researches were performed insufficiently. In this study, two sites (Gangjin and Jinhae bay) were selected for their high and low rate of mortality, respectively, and the existence of microflora from underwater sediments in the bodies of $S.$ $broughtonii$ was analyzed. We screened the whole body of each sample and chose unique colonies, which exhibit alpha- and beta-hemolytic activity, for identification. The microflora in $S.$ $broughtonii$ was less variable than sediments, and restricted species were isolated. We identified 17 genera of 88 species and 16 genera of 64 species from the two bays, respectively. A major proportion was comprised of $Bacillus$ species, with the $Bacillus$ $cereus$ group being the most common species among the $Bacillus$ strains, while $Paenibacillus$, $Lynsilbacillus$, and $Vibrio$ species were the second most abundant species. At the genus level, there were no significant microbial differences between the two coastal regions. 64 species were isolated from rare site (Jinhae bay), but more species (88) with greater variety were isolated from the frequent site (Gangjin bay). Therefore, it was assumed that the cause of mass mortality lay in the difference in specie-level diversity, and conducting investigations on the diagnosis of pathogenic species by challenging tests using isolated unique species.

• Korean Journal of Poultry Science
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• v.18 no.2
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• pp.97-119
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• 1991

Effect of Streptococcus faecium(SF) and an antibiotic, Colistin(Col), supplemented to diets singly or in combination, on the performances and changes of intestinal population of microflora of broiler chicks studied. A total of 252, day-old chicks(Arbor Acre) of mixed sex(M：F＝1：1) were alloted into six groups. A diet with no Col and SF was referred as a control diet. The basal diets were added with two levels of SF, 0.04 and 0.08%, singly or in combination with Col 10ppm Another diet was prepared by adding only Col 10 ppm. Numbers of the microorganism in diets added with SF 0.04% and 0.08% were 7$\times$10$^{4}$ and 1.4$\times$10$^{5}$ /g diet respectively The diets consisting of corn and soybean meal as major ingredients were fed for a period of seven weeks . During the feeding trial, fresh excreta were sampled at the end of every week in a sterilized condition to count microbial changes from each dietary group. Microbial changes of large intestine were also measured from nine birds sacrificed at the end of the 4th and 7th weeks each time per dietary group. Excreta from all the groups were also collected quantitatively at the end of 3rd and 6th weeks to measure digestibility of the diets, At the end of 7th week, nine birds from each group were also sacrificed to measure weight changes of gastrointestinal tracts . Average body weight gains of broilers fed the diets added with SF 0.08% (2.37kg) or SF 0. 08%+col 10ppm(2.34kg) were significantly larger than that of the control(2.18kg). The weight gains of the other groups were not statistically different from that of the control Feed/gain ratios of the supplemental groups were better than that of control (P＜0.05) except that of birds fed the diet added only with SF 0.04%. Digestibilities of nutrients such as dry matter, crude protein, crude fat and total carbohydrates were not altered by the consumption of the diets added with SF and/or Col throughout the whole feeding period. As expected, the numbers of Streptococci in the excreta from birds fed diets added with SF increased significantly with a statistical difference between groups with SF 0.04% and SF 0.08% most of the time. However. addition of Colistin to the diets supplemented with SF did not give any effects on the number of the microorganism. Numbers of coliforms in the excreta were apparently reduced by feeding the diets added with SF and/or Col(P＜0.05). There were, however, no additive effects observed between the two feed additives in this regard when supplementing Col to the SF diets. Distributions of intestinal microflora exhibited exactly the same pattern as those of the excreta. Length of small intestine of the birds fed diets added with SF 0.08% with or without Col 10 ppm became significantly longer with a range of about 10% than those of the birds fed diets without SF. However, the empty weight of the small inestine of the former group was lighter than that of control These changes resulted in a significant reduction in weight/unit length of the intestine of the birds fed diets supplemented with Col and SF singly or in combination. In overall conclusion, diet added with SF 0.08% appeared most effective in improving broiler performances. Colistin added at a level of 10ppm was not beneficial at all in itself or in combination with SF in terms of broiler performances or changes of intestinal microflora population. The efficacy of SF and Col could be attributed to the changes of wall thickness of the small intestine.

• Journal of Dairy Science and Biotechnology
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• v.22 no.1
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• pp.13-25
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• 2004

High concentration of cholesterol in the blood streams of humans has been recognized as a risk factor in the coronary heart disease. Recently, lactobacilli having high bile salt hydrolase activity have been claimed to decrease the concentration of the blood stream cholesterol in humans. In particular, many studies have been reported on the hypocholesterolemic effect of Lactobacillus acidophilus, a normal component of the microflora of the small intestine. Bile salts are excreted as bile into duodenum in the form of N-acyl compounds conjugated with glyine or taurine. Bile excretion is the major route of eliminating cholesterol from the body as well as one of the important pathways of cholesterol metabolism. Since conjugated bile salts are necessary to emulsify cholesterol, deconjugation of bile salts by lactobacilli could decrease intestinal absorption of cholesterol. Free bile salts as well as cholesterol are less soluble than the conjugated bile salts. Therefore, few free bile salts and cholesterol are absorbed through the enterohepatic circulation and most of them are easily excreted via feces. Thus, serum cholesterol could be removed from the body pool by synthesizing new conjugated bile salts to replace the excreted ones.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.166-171
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• 2002

The genus Leuconostoc is generally recognized as a favorable microorganism associated with a good taste of Kimchi and Lactobacillus plantarum is responsible for the overripening and acidification of Kimchi. A rapid and reliable PCR-based method to monitor the change of these lactic acid bacterial populations during Kimchi fermentation was attempted. A Leuconostoc-specific primer set was chosen from the conserved sequences of 16S rRNA genes among Leuconostoc species. The Lb. plantarum-specific primer set was the internal segments of a Lb. plantarum-specific probe which was isolated after randomly amplified polymorphic DNA (RAPD) analysis and tested for identification. The specificity of this protocol was examined in DNA samples isolated from a single strain. In agarose gel, as little as 10 pg of template DNA could be used to visualize the PCR products, and quantitative determination was possible at the levels of 10 pg to 100 ng template DNA. For the semi-quantitative determination of microbial changes during Kimchi fermentation, total DNAs from the 2 h-cultured microflora of Kimchi were extracted for 16 days and equal amounts of DNA templates were used for PCR. The intensities of DNA bands obtained from PCR using Leuconostoc-specific and Lb. plantarum-specific primer sets marked a dramatic contrast at the 1 ng and 100 ng template DNA levels during Kimchi fermentation, respectively. As the fermentation proceeded, the intensity of the band for Leuconostoc species increased sharply until the 5th day and the levels was maintained until the 11 th day. The sharp increase for Lb. plantarum occurred after 11 days with the decrease of Leuconostoc species. The results of this study indicate that Leuconostoc species were the major microorganisms at the beginning of Kimchi fermentation and reach their highest population during the optimum ripening period of Kimchi.

• Korean journal of food and cookery science
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• v.20 no.6 s.84
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• pp.561-567
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• 2004

The purpose of this study was to investigate the effect of Paecilomyces japonica mycelia(PJM) on pH, titrable acidity and microbiological qualify of Jeungpyun(fermented rice cake). Jeungpyun prepared with $0\~\%$ of PJM stored at $5^{\circ}C\;and\;20^{\circ}C$ for 4 weeks and 7 days respectively. Before fermentation of Jeungpyun dough, viable cells of total bacterial counts(TBC), yeasts and lactic acid bacteria(LAB) were $6.0\~9.8\times10^6,\;5.3\~9.0\times10^6,\;5.4\~8.5\times10^6\;CFU/g$, respectively. During the fermentation of dough, viable cells of TBC, yeasts and LAB increased $0.3\~0.4$ log cycle and pH was decreased whereas acidity increased as the progress of fermentation. Total viable cells in Jeungpyun before storage were $5.0\times10^1\;CFU/g$. During storage of Jeungpyun, TBC, yeasts and LAB of control group increased 2.6, 2.4, 2.1 log cycle at $5^{\circ}C$ and 4.8, 4.6, 4.5 log cycle at $50^{\circ}C$, respectively, when reached at maximum level. Major microflora of Jeungpyun was composed of yeasts and LAB during fermentation of dough and storage at $5^{\circ}C\;and\;20^{\circ}C$. Addition of PJM, inhibited the growth of microorganisms, the changes of PH and titrable acidity of Jeungpyun during storage at both of $5^{\circ}C\;and\;20^{\circ}C$. From these results, the addition of PJM extended the shelf-life of Jeungpyun during storage at $5^{\circ}C\;and\;20^{\circ}C$.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.506-510
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• 2009

The effects of various organic wastes on anaerobic fermentative hydrogen production were studied using enriched mixed microflora in batch tests. Rotten fruit, corn powder and organic wastewater enriched with sulfate (up to 1,000 mg/L) were used for experiments. Maximum hydrogen production (547.1 mL) was observed from rotten apple with initial substrate concentration of 132.2 g COD/L. The experimental result on sulfate enriched organic wastewater indicated that hydrogen production is not adversely influenced by relatively high sulfate concentration. Residual sulfate content remained at 96-98 % after 75 hours of reaction, which showed that no major sulfate reduction was occurred at pH 5.3-5.5 in the reactor. The volatile fatty acid (VFA) fractions produced during the reaction was in the order of butyrate > acetate > propionate in all experiments. The results of this study would be useful for controlling the conditions on fermentative hydrogen production using different feedstocks.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.994-998
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• 2007

Changes in microflora, pH, reducing sugar content, lactic acid content, and ethanol content during Korean rice wine fermentation were investigated. Typical quality characteristics of Korean rice wine fermentation including pH, reducing sugar content, lactic acid content, and ethanol content were evaluated. While a fungus was not detected in our Korean rice wine mash, yeast was found to be present at fairly high quantities (1.44-4.76\;{$\times}\;10^8\;CFU/mL$) throughout the fermentation period. It is assumed that lactic acid bacteria (LAB) had effects on the variations of fragrance and flavor for traditional Korean rice wine. The main LAB during the Korean rice wine fermentation was determined and identified as a Gram-positive, straight rod-shaped cell. Genotypic identification of the isolated strain by amplification of its 16S rRNA sequence revealed that the isolated strain was most closely related to Lactobacillus plantarum (99%) strains without any other comparable Lactobacillus strains. Therefore, we designated the major LAB identified from traditional Korean rice wine fermentation as L. plantarum RW.

• Journal of Dairy Science and Biotechnology
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• v.36 no.2
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• pp.81-94
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• 2018

This review discusses the characteristics of major lignans and related studies and provides a basis for future studies. Lignans are present in various food products consumed daily, such as flaxseed and other seeds, vegetables, fruits, and beverages including coffee, tea, and wine. Lignans are natural phytoestrogens with a structure similar to that of secoisolariciresinol (Seco), mataireinol (Mat), pinoresinol (Pin), medioresinol (Med), lariciresinol (Lari), and syringaresinol, which is then converted to enterodiol (END) and enterolactone (ENL), which are mammalian lignans and the primary biologically active enterolignans, by the intestinal microflora. The associations between lignans and a decreased risk of cardiovascular disease are promising; however, they are not yet well-established, probably owing to low lignan intake in habitual Western diets. Nonetheless, these associations were more prominent at the higher doses in interventional studies. Many studies on humans and animals have reported the benefits of lignan consumption in protecting against CVD and metabolic syndrome by reducing lipid and glucose concentrations. END and ENL reportedly exert protective effects including phytoestrogenic, antioxidant, anti-inflammatory, and anticancer effects through various mechanisms. Moreover, lignans reportedly exert beneficial effects in breast, colon, and prostate cancer and osteoporosis have reported that. However, future studies are required to confirm the association between lignan and disease.

• Journal of Microbiology and Biotechnology
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• v.22 no.6
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• pp.838-848
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• 2012

Orally administered herbal glycosides are metabolized to their hydrophobic compounds by intestinal microflora in the intestine of animals and human, not liver enzymes, and absorbed from the intestine to the blood. Of these metabolites, some, such as quercetin and kaempherol, are mutagenic. The fecal bacterial enzyme fraction (fecalase) of human or animals has been used for measuring the mutagenicity of dietary glycosides. However, the fecalase activity between individuals is significantly different and its preparation is laborious and odious. Therefore, we developed a fecal microbial enzyme mix (FM) usable in the Ames test to remediate the fluctuated reaction system activating natural glycosides to mutagens. We selected, cultured, and mixed 4 bacteria highly producing glycosidase activities based on a cell-free extract of feces (fecalase) from 100 healthy Korean volunteers. When the mutagenicities of rutin and methanol extract of the flos of Sophora japonica L. (SFME), of which the major constituent is rutin, towards Salmonella typhimurium strains TA 98, 100, 102, 1,535, and 1,537 were tested using FM and/or S9 mix, these agents were potently mutagenic. These mutagenicities using FM were not significantly different compared with those using Korean fecalase. SFME and rutin were potently mutagenic in the test when these were treated with fecalase or FM in the presence of S9 mix, followed by those treated with S9 mix alone and those with fecalase or FM. Freeze-dried FM was more stable in storage than fecalase. Based on these findings, FM could be usable instead of human fecalase in the Ames test.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.59-66
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• 2018

Propionibacterium acnes, a major pathogens bacterium of acne, is one of the microflora associated with the inflammation. In this study, the antibacterial effects of 70% ethanol extracts from the 61 natural plants in Jeju against P. acnes were investigated using the disc diffusion method. The 45 natural plant extracts showed antibacterial effects and the 16 natural plants extracts didn't show antibacterial effects. The Phyllanthus urinaria L. (stem and leaves) extract showed thr highest antimicrobial activity with $18.96{\pm}0.69mm$ clear zone of the growth of P. acnes, followed by Angelica gigas Nakai (roots), Gynostemma pentaphyllum (Thunb.) Makino, Angelica gigas Nakai (stem and leaves), Isodon inflexus (Thunb.) Kudo, camellia sinensis L. (flowers), Rosmarinus officinalis, etc. These results suggest that the natural plant in Jeju can be used as functional cosmetic biomaterials or antimicrobial agents against P. acnes.