• Applied Biological Chemistry
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• v.46 no.4
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• pp.367-375
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• 2003

The puree of Rubus coreanus was fermented using lactic acid bacteria and its biological activities were examined. Lactobacillus acidophilus KCCM 32820, L. casei KCCM 12452, Lactococcus lactis subsp. lactis KCCM 40104, and Streptococcus thermophilus KCCM 40430 were used as a single or mixed starter for the lactic acid fermentation, and their cultures at the late logarithmic growth phase were inoculated to final concentration of 2% (v/v). L. casei fermented the puree of Rubus coreanus best when used as a single starter, and the culture of L. casei and L. lactis with the inoculation ratio of one to one showed the highest fermentation activity when used as a mixed starter. However, the fermented broth of the puree of Rubus coreanus using L. acidophilus and S. thermophilus showed the best results in the sensory evaluation. The optimal lactic acid fermentation conditions were as follows; the concentration of oligosaccharide added was 1% (w/v), pH of puree and fermentation temperature were 4.0 and $37^{\circ}C$, respectively, and fermentation time was $72{\sim}96$ hours. Glucose and fructose were major free sugars, and the content of lactic acid was 698.2 mg/100 g in the fermented broth. The fermented broth of the puree of Rubus coreanus showed the electron donating ability and nitrite scavenging ability with the value of 69% and 38.3% at pH 1.2, respectively. SOD-like activity and inhibitory activity on xanthine oxidase were also found in the fermented broth with the value of 60.3% and 41.8%, respectively. When the antimicrobial activities of the fermented broth were examined, it showed the highest growth inhibitory activity against Escherichia coli O-157:H7, and also contained antimicrobial activities against Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.623-625
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• 2000

Bacteriocin-producing lactic acid bacteria was isolated from Kimchi using MRS as selective media and Lactobacillus delbruekii subsp. delbruekii as an indicator strain. Strain JC-3 was tentatively identified as Lactococcus latis subsp. lactis through the API test and the bacteriocin produced by JC-3 showed the inhibitory activity against Grampositive pathogens and other lactic acid bacteria. The antimicrobial substance was inactivated by Protamax, Aroase AP-10, Neutrase, R-AMANO and was confirmed to be heating at $100^{\circ}C$. However, it was lost at high pH values showed the highest bacteriocin activity at a culture temperature of $30^{\circ}C$. The bacteriocin was partially purified by ammonium sulfate precipitation, Sep-pak $C_{18}$ cartridge. The apparent molecular mass of the bacteriocin was about 8 Kda, which was determined through the direct detection of bactericidal activity using SDS -PAGE.

• Journal of Life Science
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• v.30 no.6
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• pp.532-541
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• 2020

In this study, we describe the inhibition of adipocyte differentiation by the lactic acid bacteria (LAB) fermentation product of Chrysanthemum indicum L. (CI) extract to control obesity. Preparation of LAB-fermented products was performed to overcome the cytotoxicity of CI extract. During fermentation and 3T3-L1 cell line experiment, cytotoxicity was not induced in the CI fermentation products over 1 day in culture. Fermented materials from highly proliferative cultures were selected for treatment of 3T3-L1 cells and for comparison with unfermented control groups. Cell survival and undifferentiated cell populations were decreased differentiation population in all experimental groups compared with controls, as measured using fluorescence-activated cell sorting analysis. Akt pathway activity increased upon treatment with these fermented extracts in 3T3-L1 cells. Gli2 depleted at the protein level in association with adipocyte differentiation. LAB KCTC 3115- and 3109-fermented extract treatment caused controlled Gli2 protein accumulation. Moreover, KCTC 3115 and 3109 were found to reduce C/EBPα and FAS was depleted, whereas pACC was increased at the protein level upon treatment with the fermentation products of each of the four LAB used in this study. With Lactococcus lactis subsp. lactis KCTC 3115 fermentation, the regulation of adipose differentiation and hedgehog signaling were also suppressed, thereby inhibiting the differentiation of progenitor cells. The basis for the activation of hedgehog signaling may provide insights into the treatment of obesity and the inhibition of adipocyte differentiation.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.2
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• pp.285-294
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• 2011

The abatement of methane emission from ruminants is an important global issue due to its contribution to greenhouse gas with carbon dioxide. Methane is generated in the rumen by methanogens (archaea) that utilize metabolic hydrogen ($H_2$) to reduce carbon dioxide, and is a significant electron sink in the rumen ecosystem. Therefore, the competition for hydrogen used for methanogenesis with alternative reductions of rumen microbes should be an effective option to reduce rumen methanogenesis. Some methanogens parasitically survive on the surface of ciliate protozoa, so that defaunation or decrease in protozoa number might contribute to abate methanogenesis. The most important issue for mitigation of rumen methanogenesis with manipulators is to secure safety for animals and their products and the environment. In this respect, prophylactic effects of probiotics, prebiotics and miscellaneous compounds to mitigate rumen methanogenesis have been developed instead of antibiotics, ionophores such as monensin, and lasalocid in Japan. Nitrate suppresses rumen methanogenesis by its reducing reaction in the rumen. However, excess intake of nitrate causes intoxication due to nitrite accumulation, which induces methemoglobinemia. The nitrite accumulation is attributed to a relatively higher rate of nitrate reduction to nitrite than nitrite to ammonia via nitroxyl and hydroxylamine. The in vitro and in vivo trials have been conducted to clarify the prophylactic effects of L-cysteine, some strains of lactic acid bacteria and yeast and/or ${\beta}$1-4 galactooligosaccharide on nitrate-nitrite intoxication and methanogenesis. The administration of nitrate with ${\beta}$1-4 galacto-oligosaccharide, Candida kefyr, and Lactococcus lactis subsp. lactis were suggested to possibly control rumen methanogenesis and prevent nitrite formation in the rumen. For prebiotics, nisin which is a bacteriocin produced by Lactococcus lactis subsp. lactis has been demonstrated to abate rumen methanogenesis in the same manner as monensin. A protein resistant anti-microbe (PRA) has been isolated from Lactobacillus plantarum as a manipulator to mitigate rumen methanogenesis. Recently, hydrogen peroxide was identified as a part of the manipulating effect of PRA on rumen methanogenesis. The suppressing effects of secondary metabolites from plants such as saponin and tannin on rumen methanogenesis have been examined. Especially, yucca schidigera extract, sarsaponin (steroidal glycosides), can suppress rumen methanogenesis thereby improving protein utilization efficiency. The cashew nutshell liquid (CNSL), or cashew shell oil, which is a natural resin found in the honeycomb structure of the cashew nutshell has been found to mitigate rumen methanogenesis. In an attempt to seek manipulators in the section on methane belching from ruminants, the arrangement of an inventory of mitigation technologies available for the Clean Development Mechanism (CDM) and Joint Implementation (JI) in the Kyoto mechanism has been advancing to target ruminant livestock in Asian and Pacific regions.

• Korean Journal of Veterinary Service
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• v.29 no.3
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• pp.277-285
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• 2006

Plasmids are covalently closed circular molecules of DNA that are stably inherited and replicate somewhat independently of the bacterial chromosome. Genes carried on plasmids can mediate a wide variety of important functions, including antibiotics (R plasmids) and heavy metals resistance, toxins production, cell penetration, iron chelation, complement resistance, and metabolic characteristics such as sucrose and lactose fermentation. Fifty strains of lactobacilli were isolated from 26 staters and 29 fermented milk products. They were classified 27 strains as Lactobacillus paracasei subsp paracasei, 11 stains as Lactococcus lactis subsp cremoris, 6 strains as L delbrueckii subsp lactis, 4 strains as L acidophius, and 2 strains as L delbrueckii subsp bulgaricus. All of these strains were examined for drug resistance and transferability of R plasmids. All of the isolates were sensitive to Am, C, CF, E, NB, P, T, and Te. But resistant to SXT 94% (47 strains), K 66% (33 strains), S 56% (28 strains), ENR 50% (25 strains), NOR 38% (19 strains) CIP 38% (19 strains), GM 16% (8 strains), and N 14% (7 strains), in order. And 32 different resistant patterns were found. The most frequently encountered patterns were CIP-ENR-K-NOR-S-SXT (5 strains). In vitro R plasmids transfer experiment, 57 antibiotic resistant strains which were not transfer to the recipient 2 Escherichia coli strains by conjugation, These results indicate that Lactobacillus in internal trade market' stater recognize R factor but transmissible R plasmid is not existed.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1123-1132
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• 2015

Winter wheat is a suitable crop to be ensiled for animal feed and China has the largest planting area of this crop in the world. During the ensiling process, lactic acid bacteria (LAB) play the most important role in the fermentation. We investigated the natural population of LAB in whole-crop wheat (WCW) and examined the quality of whole-crop wheat silage (WCWS) with and without LAB inoculants. Two Lactobacillus plantarum subsp. plantarum strains, Zhengzhou University 1 (ZZU 1) selected from corn and forage and grass 1 (FG 1) from a commercial inoculant, were used as additives. The silages inoculated with LAB strains (ZZU 1 and FG 1) were better preserved than the control, with lower pH values (3.5 and 3.6, respectively) (p<0.05) and higher contents of lactic acid (37.5 and 34.0 g/kg of fresh matter (FM), respectively) (p<0.05) than the control. Sixty LAB strains were isolated from fresh material and WCWS without any LAB inoculation. These LAB strains were divided into the following four genera and six species based on their phenotypic, biochemical and phylogenetic characteristics: Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, Lactococcus lactis subsp. lactis, Lactobacillus buchneri, and Lactobacillus plantarum subsp. plantarum. However, the prevalent LAB, which was predominantly heterofermentative (66.7%), consisted of Leuconostoc pseudomesenteroides, Leuconostoc citreum, Weissella cibaria, and Lactobacillus buchneri. This study revealed that most of isolated LAB strains from control WCWS were heterofermentative and could not grow well at low pH condition; the selective inoculants of Lactobacillus strains, especially ZZU 1, could improve WCWS quality significantly.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.303-310
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• 2002

An optimization for fermentation processes to make lactic acid juice with extracts from apples, carrots, celery, watercress, jujube and lycii (3 : 3 : 1 : 1/2 : 1 : 1/2) using co-cultures of Leuconostoc mesenteroides, Lactococcus lactis and Lactobacillus cellobiosus isolated from Dongchimi had been investigated on the emphasis of composition of sugars and sodium chloride at various temperatures. The concentration of sugars less than 25% and salt less than 0.8% did not affect remarkably the cell growth of lactic acid bacteria and acid formation during fermentation. The fermenting juice showed increases in the population of lactic acid bacteria and acidity, and decreases in population of coliform bacteria and sugar concentration with high cultural temperature. At $25^{\circ}C$ viscous substance was not formed as it had at $15^{\circ}C$. The optimum composition, based on the sensory evaluation, was determined to be oligosaccharide and 0.2% for sodium chloride. It took 3 days to produce the most preferable juice of pH 3.62 at $25^{\circ}C$. At the optimal state the fermented juice showed viable cell counts (cfu/mL) of exponential numbers 8 for lactic acid bacteria and 4 for yeast. Coliform bacteria which had been $5.6{\times}10^2\;cfu/mL$ at the beginning of fermentation were not detected.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.499-507
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• 2016

In this study, traditional culture method and 16S rRNA gene analysis were applied to reveal the composition and diversity of lactic acid bacteria (LAB) of fermented cow milk, huruud and urum from Baotou and Bayannur of midwestern Inner Mongolia. Also, the quantitative results of dominant LAB species in three different types of dairy products from Baotou and Bayannur were gained by quantitative polymerase chain reaction (q-PCR) technology. Two hundred and two LAB strains isolated from sixty-six samples were identified and classified into four genera, namely Enterococcus, Lactococcus, Lactobacillus, Leuconostoc, and twenty-one species and subspecies. From these isolates, Lactococcus lactis subsp. lactis (32.18%), Lactobacillus plantarum (12.38%) and Leuconosto mesenteroides (11.39%) were considered as the dominated LAB species under the condition of cultivating in MRS and M17 medium. And the q-PCR results revealed that the number of dominant species varied from samples to samples and from region to region. This study clearly shows the composition and diversity of LAB existing in fermented cow milk, huruud and urum, which could be considered as valuable resources for LAB isolation and further probiotic selection.

• 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 Microbiology and Biotechnology
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• v.33 no.4
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• pp.500-510
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• 2023

In this study, lactic acid bacteria were isolated from 21 top-selling probiotic products on Korean market and their antimicrobial resistance were analyzed. A total 152 strains were claimed to be contained in these products and 70 isolates belonging to three genera (Bifidobacterium, Lactobacillus, and Lactococcus) were obtained from these products. RAPD-PCR showed diversity among isolates of the same species except for two isolates of Lacticaibacillus rhamnosus from two different products. The agar dilution method and the broth dilution method produced different MICs for several antimicrobials. With the agar dilution method, five isolates (three isolates of Bifidobacterium animalis subsp. lactis, one isolate of B. breve, one isolate of B. longum) were susceptible to all nine antimicrobials and 15 isolates were multi-drug resistant. With the broth microdilution method, only two isolates (one isolate of B. breve and one isolate of B. longum) were susceptible while 16 isolates were multi-drug resistant. In this study, only two AMR genes were detected: 1) lnu(A) in one isolate of clindamycin-susceptible and lincomycin-resistant Limosilactobacillus reuteri; and 2) tet(W) in one tetracycline-susceptible isolate of B. longum B1-1 and two tetracycline-susceptible isolates and three tetracycline resistant isolates of B. animalis subsp. lactis. Transfer of these two genes via conjugation with a filter mating technique was not observed. These results suggest a need to monitor antimicrobial resistance in newly registered probiotics as well as probiotics with a long history of use.