• Korean Journal of Microbiology
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• v.54 no.4
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• pp.398-409
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• 2018

In the present study, biogenic amine-forming Bacillus spp. and bacteriocin-producing lactic acid bacteria (LAB) isolated from Doenjang were generally identified through 16S rRNA gene sequencing, and the physicochemical and microbiological characteristics of cheonggukjang prepared using the isolated strains were investigated. Biogenic amine-producing bacteria from the samples were identified as Bacillus licheniformis DB102, B. subtilis DB203, B. stearothermophilus DB206, B. pumilus DB209, B. subtilis DB310, B. coagulans DB311, B. cereus DB313, B. amyloliquefaciens DB714, B. amylolique-faciens DB915, B. licheniformis DB917, B. cereus DB1019, B. subtilis DB1020, B. megaterium DB1022. The bacteriocin-producing LAB showed antibacterial effect against biogenic amine-producing Bacillus spp. were identified as Lactobacillus plantarum DLA205, L. brevis DLA501, L. fermentum DLA509, L. acidophilus DLA703, and Enterococcus faecalis DLA804. The bacteriocin produced by the LAB significantly decreased the viable numbers and the amine production ability of the biogenic amine-forming Bacillus spp. in a concentration dependent manner. Therefore, the pH, ammonia nitrogen and biogenic amine content of cheonggukjang prepared by mixed culture of the LAB and Bacillus spp. were significantly decreased compared to the control group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1476-1480
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• 2016

Anti-microbial effects of the medium extracts from three different lactic acid bacteria (LB1, Lactobacillus acidophilus; LB2, Lactobacillus casei; LB3, Lactobacillus sicerae) were investigated. Three different extracts of lactic acid bacteria media (ELAM) did not show significant changes in pork loin quality after 3 and 14 days of cold storage such as general contents, colors, pH, and TBARS. To determine anti-bacterial activity of three ELAM, three pathogenic bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus) were obtained and incubated with ELAM-absorbed paper discs. ELAM of LB2 and LB3 showed significantly larger bacterial growth inhibitory zones compared with that of LB1 (P<0.05). When the pathogenic bacteria inoculated in pork loin with three ELAM, total microbial contents of pork loin treated with ELAM of LB3 after 14 days of cold storage showed significantly lower microbial contents compared to those of control, LB1 and LB2 (P<0.05). In conclusion, ELAM of LB3 derived from L. sicerae had the most effective pathogenic bacteria inhibitory activity on agar and pork loin. This is the first result to report the antibacterial effect of L. sicerae. If the safety and toxicity characteristics of L. sicerae are further investigated, this new lactic acid bacterium would have potential as an effective and nature-friendly food preserving agent.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.23-32
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• 1989

This experiment was performed to investigate the growth and acid production of lactic acid bacteria in soy yoghurts prepared from soybeans produced using various nitrogen sources and the ability of the bacteria to utilize the available carbohydrates in the medium. Various soybeans did not show significant difference in the growth and acid production of lactic acid bacteria, soybean D with newly developed complex fertilizer being the best. The acid production in soy milk by L. acidophilus was better than those in defatted soy milk and in isolated soy protein, that in isolated soy milk being significantly poor. Of lactic acid bacteria tested, L bulgaricus and L. acidophilus exhibited more population and acid production in soy yoghurts. The population and acid production of lactic acid bacteria was increased by the addition of various carbohydrates, and significantly by glucose and yeast extract.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.192-199
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• 2000

Lactic acid bacteria (LAB) fermented food was prepared from milk or egg white powder (EWP) and added with five kinds of freeze drying protectant (FDP). Effects of FDP on growth and acid production of LAB were investigated. Effects of FDP on organoleptic properties of LAB fermented food were also studied. (1) Some of FDPs showed protective effect against damage to Lactobacillus acidophilus in LAB fermented food during freeze drying, while FDP did not show any protective effect against damage to L. acidophilus during freezing. This protective effect differed with substrate and concentration of FDP (2) Optimum concentration of Tween 80 and ascorbate added to milk sample was 0.2 % (W/V) and 1 %(W/V), respectively. Optimum concentration of raffinose and ascorbate added to EWP sample was 3 %(W/V) and 1 %(W/V), respectively (3) Among FDPs added to L. casei fermented food, raffinose and ascorbate added to EWP sample showed FDP effect. Among FDPs added to L. delbrueckii fermented food, raffinose added to EWP sample showed FDP effect. (4) Samples added with MSG showed MSG taste. Milk sample added with ascorbate showed slightly more acid taste than reference sample, while taste of EWP sample added with ascobate did not differ with reference sample. Tween 80 added to milk sample or EWP sample improved texture of LAB fermented food.

• Journal of Dairy Science and Biotechnology
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• v.35 no.4
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• pp.255-261
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• 2017

The purpose of this study was to investigate the probiotic properties and antioxidant capacity of lactic acid bacteria isolated from Vietnamese feces and the Korean traditional food kimchi. Six isolated strains were identified as Lactobacillus sp. by 16S rRNA sequencing. All strains showed good resistance to low pH (1.5, 2.0, and 3.0) and 0.3% oxgall bile acids. Culture filtrates from the six strains showed various antioxidant effects, including DPPH, ABTS, reducing power, and metal chelating ($Fe^{2+}$) activities. Two of the six Lactobacillus strains showed potential probiotic activity. Heat resistance and adhesion assays were conducted by mixing the selected strains, Lactobacillus acidophilus V4, Lactobacillus plantarum V7, and Lactobacillus paracasei DK121 isolated from kimchi. The results showed that the heat resistance of these strains was similar to that of a commercial strain, L. plantarum LP. In addition, a mucin attachment assay using the mixture of selected strains (V4, V7, and DK121) showed high binding activity to the mucous layer. In conclusion, a mixture of V4, V7, and DK121 shows promising probiotic activity and may be useful for the development of health-related products.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.149-155
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• 2020

This study was conducted to investigate the potential prebiotic activity of an extract from yacon tuberous root on the growth of probiotic strains Bifidobacterium and Lactobacillus. Results showed that the amount of fructooligosaccharides per 100 g fresh root was the highest (7.60 g), followed by sucrose (0.72 g), fructose (0.34 g), and glucose (0.26 g). The in vitro culture test of intestinal beneficial bacteria, including Bifidobacterium longum BORI, B. bifidum BGN4, and B. lactis AD011 showed effective growth on the MRS-Yacon medium containing yacon extract, whereas the growth of Lactobacillus acidophilus AD031, L. plantarum BH02, and L. fermentum BH03 did not differ from that of the control groups. In particular, B. longum BORI showed better growth than the control group after 10 h of incubation. These results indicate that yacon can be a natural prebiotic source of fructooligosaccharides, which can exert a prebiotic effect on intestinal microflora by selectively enriching Bifidobacterium.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.430-434
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• 2003

In vivo antagonistic effect of Lactobacillus helveticus CU 631 and Lactobacillus spp. against typical enteritis causing pathogen Salmonella enteritidis KU 101 have been determined, which showed an increase in survival rate and the decline in viable cell numbers of pathogen in liver and spleen at sacrifice. A signifcant difference in the antagonistic effect against KU 101 were observed, which was species and/or strain dependent of Lactobacillus (p<0.01), the survival rate of the mice in the Salmonella infection by feeding L. helveticus CU 631 has been shown to be 157%, whereas those of L. rhamnosus GG ATCC 53103, L. acidophilus ATCC 4356, L. johnsonii C-4 were 137%, 132%, 119% respectively on the basis of lactobacilli non-associated control KU101 fed mice to be 100%. Viable cells of S. enteritidis KU101 in the liver and in the spleen at sacrifice were decreased in Lactobacillus spp. fed group with no significant difference. The higher level of total secretory IgA concentration in the intestinal fluid of lactobacilli fed mice than control mice have been observed. In vitro antagonistic activity of Lactobacillus spp. against KU101 have been determined, a prominent antagonistic activity of CU 631 against KU 101 were demonstrated.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.5
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• pp.495-504
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• 1997

Three media, i. e., MOD-SD, M98-5 and M98-5 supplemented with chicken fecal extract were tested as isolation media for anaerobic bacteria present in the duodenum, jeju-ileum and cecum of chicken. The results showed that the mean colony counts of medium M98-5 were similar with those of MOD-SD medium in all intestinal samples at the incubation periods of 2, 6 and 10 days. Supplementation with chicken fecal extract of M98-5 medium significantly increased (p < 0.05) the colony counts of bacteria from the duodenum, jeju-ileum and cecum. The colony counts at 6-day incubation were similar with those at 10-day incubation, but were much higher than the counts at 2-day incubation. The major types of bacteria found in the duodenum and jeju-ileum of chicken were tentatively identified as Lactobacillus, Streptococcus and E. coli. In the cecum, ten tentatively identified groups of bacteria, namely, Streptococcus, Staphylococcus, Lactobacillus, E. coli, anaerobic coccus, Eubacterium, Propionibacterium, Clostridium, Fusobacterium and Bacteroides were isolated. Anaerobes were found to comprise nearly the entire microbial population of the cecum. Predominating in all sections of the intestine were homofermentative lactobacilli. The main Lactotacillus species in chicken intestine were L. acidophilus, L. fermentum and L. brevis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.269-276
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• 2014

This study was conducted to determine the quality of italian ryegrass (IRG) and whole- crop barley (WCB) silage combined with heterofermentative lactic acid bacteria (LAB) during fermentation. Six strains of LAB (L. plantarum IMAU 70164, L. acidophilus KACC 12419, L. casei KACC 12413, L. reuteri KCTC 3594, L. buchneri KACC 12416 and L. diolivorans KACC 12385) were used in this study. L. casei and L. reuteri had the highest propionic acid production and were therefore used for fermenting the forages. The forages were fermented using monoculture and co-culture of L. casei and L. reuteri for 30, 45 and 60 days of ensiling. Addition of LAB lowered the pH of the IRG silage (p<0.05). Moisture content, lactic acid and acetic acid contents were higher (p<0.05) after addition of LAB. Water soluble carbohydrate was significantly lower (p<0.05) in WCB with a co-culture containing L. casei and L. reuteri. Propionic acid production was comparatively higher after addition of LAB to WCB on days 30, 45 and 60 while butyric acid was only detected in the IRG control on day 60. Fungi was not detected within 60 days after addition of LAB in IRG and WCB. Through this experiment, improved forage preservation was achieved using a co-culture containing L. casei and L. reuteri. WCB silage had higher propionic acid concentration and thus, it was a better forage for ensiling using co-culture of L. casei and L. reuteri.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.511-516
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• 2006

The objectives of this study was to compare the probiotic characteristics of lactic acid bacteria (LAB) for their ability to assimilate cholesterol, production of bacteriocin, inhibition of angiotensin I-converting enzyme (ACE), and viability under artificial gastrointestinal fluids. Among tested lactic acid bacteria, L167 strain exhibited the highest ACE inhibitory activity (58.75%). The production of ACE inhibitory peptide derived from fermented milk by L167 strain started at the beginning of stationary phase with maximum activity occurring late of the stationary phase. The highest ACE inhibitory activity was observed at 20 h in 10% skim milk medium. L155 strain exhibited cholesterol assimilation activity compared with probiotic strains such as Lactobacillus acidophilus ATCC 43121. With addition of bacteriocin culture, viable cells of Staphylococcus aureus in fermented sausage were slightly decreased during storage. Among selected strains of LAB, 3 strains weve identified as L. plantarum (L155, L165, L167), and two strains were identified as Pediococcus damnosus (L12) and L. paracasei ssp. paracasei (P113) by use of API carbohydrate fermentation pattern and physiological tests.