• Asian-Australasian Journal of Animal Sciences
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• v.27 no.5
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• pp.648-657
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• 2014

Silage making has become a significant method of forage conservation worldwide. To determine how tomato pomace (TP) may be used effectively as animal feed, it was ensilaged for 90 days and microbiology counts, fermentation characteristics and chemical composition of tomato pomace silage (TPS) were evaluated at the 30th, 60th, and 90th days, respectively. In addition, 103 lactic acid bacteria were isolated from TPS. Based on the phenotypic and chemotaxonomic characteristics, 16S rDNA sequence and carbohydrate fermentation tests, the isolates were identified as 17 species namely: Lactobacillus coryniformis subsp. torquens (0.97%), Lactobacillus pontis (0.97%), Lactobacillus hilgardii (0.97%), Lactobacillus pantheris (0.97%), Lactobacillus amylovorus (1.9%), Lactobacillus panis (1.9%), Lactobacillus vaginalis (1.9%), Lactobacillus rapi (1.9%), Lactobacillus buchneri (2.9%), Lactobacillus parafarraginis (2.9%), Lactobacillus helveticus (3.9%), Lactobacillus camelliae (3.9%), Lactobacillus fermentum (5.8%), Lactobacillus manihotivorans (6.8%), Lactobacillus plantarum (10.7%), Lactobacillus harbinensis (16.5%) and Lactobacillus paracasei subsp. paracasei (35.0%). This study has shown that TP can be well preserved for 90 days by ensilaging and that TPS is not only rich in essential nutrients, but that physiological and biochemical properties of the isolates could provide a platform for future design of lactic acid bacteria (LAB) inoculants aimed at improving the fermentation quality of silage.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.133-141
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• 1999

Juice of Dongchime a Korean traditional vegetable food fermented with lactic acid bacteria has been traditionary used as broth for Naengmyon a Korean cold noodles with broth. This study was carried out to demonstrate the growth inhibition of two food born pathogens Listeria monocytogenes and Escherichia coli O157:H7 in Naengmyon-broth containing Dongchimi-juice fermented with high antibacterial lactic acid bacteria Lactobacillus homohiochii B21 and Leuconostoc mesenteroides C16. Naengmyon-broth were made with beef broth and Dongchimi-juice fermented with lactic acid bacteria and the changes in viable cell counts of the inoculated pathogens in Naengmyon-broths were investigated during storage at 2$0^{\circ}C$ and 1$0^{\circ}C$. In Naengmyon-broth of 100% Dongchimi-juice stored at 2$0^{\circ}C$ the numbers of Listeria monocyto-genes and Escherichia coli O157:H7 were rapidly decreased from 106CFU/ml to 106CFU/ml in 8 hours and 40 hours respectively. In Naengmyon-broth containing 50% Dongchimi-juice their numbers were also rapidly decreased though the decreasing rates were not so fast as those in 1005 Dongchimi-juice. In Naengmyon-broth containing 10% Dongchimi-juice the growths of the two pathogens were markedly inhibited compared with those in 100% beef broth though some growths were occurred in early phase. But in Naengmyon-broth of 100% beef broth their growths were very fast from early. Antibacterial ac-tivity of the Dongchimi-juice was more distinct at 2$0^{\circ}C$ than at 1$0^{\circ}C$ and was more active against Listeria monocytogenes than against Escherichia coli 157:H7.

• Journal of Dairy Science and Biotechnology
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• v.31 no.1
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• pp.51-58
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• 2013

Emerging studies suggest that vegetables or fruit juices deemed to be potential alternative base medium for lactic acid bacteria fermentation. Until now, limited studies have been carried out to evaluate such applications. Thus, the objective of present study is that lactic acid bacteria were evaluated for their viability at low pH, growth during storage at low temperature, and $CO_2$ formation. Furthermore, the effects of grapefruit extract with respect to cell viability, sensory ability, and organic acid production were evaluated for these strains. The probiotic properties of the strains, including acid tolerance, bile tolerance, and adhesion to human intestinal epithelial cells (HT-29 cells), prebiotic characteristics, and safety features were examined. All strains survived in MRS medium broth adjusted to pH 3.8, at $10^{\circ}C$ for 6 days, and did not produce $CO_2$ to check post fermentation. The medium of grapefruit extract fermentation by Lactobacillus plantarum CJIH 203 resulted in maximal viable counts, compared with other strains, and the extract subsequently tasted sour due to the presence of lactic acid. Lactobacillus plantarum CJIH203 was highly resistant to artificial gastric juice and intestinal juice, while Lactococcus lactis SJ09 strongly adhered to HT-29 cells. Tagatose showed the greatest ability to enhance the growth of L. plantarum SJ21, relative to the other strains. All strains were verified by safety tests such as hemolysis, gelatin hydration, and urea degradation. Therefore, these strains could be promising candidates for use in reducing excessive post-fermentation and functional products.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.491-498
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• 2017

Objective: Bacterial abundance and community compositions have been examined in Asian dust events, clarifying their impacts on public health. This study aims to determine the bacterial community compositions and viable bacteria in Asian dust particles in the Asian dust or non-Asian dust event of March 2016. Methods: The dust samples were collected using the high volume air sampler or high volume cascade impactor, and bacterial 16S rRNA genes were amplified using PCR, followed by pyrosequencing. Bacterial diversity index, richness estimate and community composition in the particles were analyzed from the sequencing data using Mothur software. Results: The results showed that the diversity and richness during Asian dust events were higher than them in non-Asian dust events. The total bacterial community analysis showed that at the phylum Proteobacteria, Actinobacteria and Firmicutes were the most dominant of Asian dust events and non-Asian dust events. In addition, the bacterial colony counts were higher during Asian dust event, comparing with non-Asian dust event. Conclusions: This study showed that bacterial community and richness of Asian dust samples was more complex and higher than non-Asian dust samples in Gyeonggi-do, Korea, which could affect public health and environment. Thus, the continuous monitoring of Asian dust could be an alternative for managing airborne bacteria.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.3
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• pp.169-173
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• 2014

The aim of present study was to improve the quality of silage using lactic acid bacteria (LAB) and chlorella as a supplement. Italian ryegrass (IRG) mediated silage was prepared with lactic acid bacteria (L. plantarum) and different concentration of chlorella. We analyzed the nutritional profiles such as crude protein (CP), acid detergent fiber (ADF) neutral detergent fiber (NDF), total digestible nutrient (TDN) and in-vitro dry matter digestibility (IVDMD), microbial counts and fermentative acids such as lactic acid, acetic acid and butyric acid in the control and experimental silage after three months. It shows increased crude protein content and also maintains the rest of nutritional values as compared with control silage. LAB inoculation with chlorella as supplementation slightly reduced the pH of the silage. In addition, it increased the fermentative acids production as compared with control silage and inhibits the undesired microbial growth especially fungi in the silage. Therefore, we suggest that LAB inoculation and chlorella supplementation to the IRG mediated silage could be improved the nutritional quality of the silage which is an intrinsic feature for the application in the preparation of animal feeds and functional foods.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.683-691
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• 2015

The objective of this study was to identify the coccoidal bacteria present in 188 samples of fermented yaks’, mares’ and cows’ milk products collected from 12 different regions in Mongolia. Furthermore, we evaluated the fermentation properties of ten selected isolates of the predominant species, Streptococcus (S.) thermophiles, during the process of milk fermentation and subsequent storage of the resulting yoghurt at 4℃. Overall, 159 isolates were obtained from 188 samples using M17 agar. These isolates were presumed to be lactic acid bacteria based on their gram-positive and catalase-negative properties, and were identified to species level using 16S rRNA gene sequence analysis. These coccoid isolates were distributed in four genera and six species: Enterococcus (E.) durans, Enterococcus (E.) faecalis, Lactococcus (Lac.) subsp. lactis, Leuconostoc (Leuc.) lactis, Leuconostoc (Leuc.) mesenteroides. subsp. mesenteroides and S. thermophilus. Among these S. thermophilus was the most common species in most samples. From evaluation of the fermentation characteristics (viable counts, pH, titratable acidity [TA]) of ten selected S. thermophilus isolates we could identify four isolates (IMAU 20246, IMAU20764, IMAU20729 and IMAU20738) that were fast acid producers. IMAU20246 produced the highest concentrations of lactic acid and formic acid. These isolates have potential as starter cultures for yoghurt production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.655-660
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• 2006

The purpose of this study was to analyze the microbiological hazards of prepared foods, raw materials, utensils and workers' hands and to evaluate cross-contamination of bacteria in foodservice establishments. Aerobic plate counts, coliforms, E. coli, E. coli O157:H7, Salmonella spp., Staphylococcus aureus and Listeria monocytogenes were tested. According to the microbiological evaluation, there were many cases of contamination of bacteria. Staphylococcus aureus was detected in chicken stew (Korean type), Japchae, Bibimbap and Kongnamul-muchim at the A foodservice establishment and Jwieochae-jorim at the B foodservice establishment. E. coli was detected in Ojingeochae-muchim at the C foodservice establishment. E. coli O157:H7, Salmonella spp. and Listeria monocytogenes were not detected in any of the tested samples. Critically, microbiological contamination of raw materials, utensils and workers' hands could result in contamination of prepared foods, thus, attention needs to be given to sanitation of raw materials, workers' hands and utensils to reduce or eliminate contamination of bacteria.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.283-291
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• 2012

Bioremediation efforts often rely on the application of surfactants to enhance hydrocarbon bioavailability. However, synthetic surfactants can sometimes be toxic to degrading microorganisms, thus reducing the clearance rate of the pollutant. Therefore, surfactant-resistant bacteria can be an important tool for bioremediation efforts of hydrophobic pollutants, circumventing the toxicity of synthetic surfactants that often delay microbial bioremediation of these contaminants. In this study, we screened a natural surfactant-rich compartment, the estuarine surface microlayer (SML), for cultivable surfactant-resistant bacteria using selective cultures of sodium dodecyl sulfate (SDS) and cetyl trimethylammonium bromide (CTAB). Resistance to surfactants was evaluated by colony counts in solid media amended with critical micelle concentrations (CMC) of either surfactants, in comparison with non-amended controls. Selective cultures for surfactant-resistant bacteria were prepared in mineral medium also containing CMC concentrations of either CTAB or SDS. The surfactantresistant isolates obtained were tested by PCR for the Pseudomonas genus marker gacA gene and for the naphthalene-dioxygenase-encoding gene ndo. Isolates were also screened for biosurfactant production by the atomized oil assay. A high proportion of culturable bacterioneuston was tolerant to CMC concentrations of SDS or CTAB. The gacA-targeted PCR revealed that 64% of the isolates were Pseudomonads. Biosurfactant production in solid medium was detected in 9.4% of tested isolates, all affiliated with genus Pseudomonas. This study shows that the SML is a potential source of surfactant-resistant and biosurfactant-producing bacteria in which Pseudomonads emerge as a relevant group.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.334-344
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• 2014

The objective of this study was to evaluate the microbiological and physicochemical characteristics, and the antagonistic activity against Helicobacter pylori ATCC 43504, of yogurt fermented with the lactic acid bacteria from Baikkimchi kept under cold storage. The viable cell counts, titratable acidity, viscosity, and total solid content of the yogurt were different according to the bacterial strains used for fermentation. There was no significant change (P>0.05) in the various properties of refrigerated yogurt. Among the tested strains, the strongest resistance against artificial gastric juice and bile salt was found for Lactobacillus brevis BK11 and Lactobacillus paracasei BK57. Due to high lactic acid levels obtained from these two lactic acid bacteria, yogurt may show good anti-Helicobacter effects according to the time-kill assay. In particular, yogurt fermented with L. brevis BK11 significantly reduced the number of H. pylori adhering to gastric epithelial AGS cells and the urease activity of this pathogen (P<0.05).

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.494-503
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• 2019

The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, ${\gamma}$-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.