• Journal of Dairy Science and Biotechnology
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• v.22 no.2
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• pp.91-97
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• 2004

The antioxidative ability on the basis of reduced glutathione sulphydryl(GSH) level, the inhibition activities of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and Bacillus spp. have been determined; Lactobacillus casei CU4114 contained the highest level of GSH among the probiotic strains with 25.15 ${\mu}$mole/g. Significantly high level of GSH occured in the intracellular cell free extract of Lactobacillus rhamnosus CU4201, Lactobacillus plantarum CU4203. The antioxidant activity and inhibition of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and Bacillus spp. by thiobarbituric acid(TBA) assay have been shown to be significantly differed depending on the strains(P>0.01). Intracellular cell free extracts of L. acidophilus CU4111, L. casei CU4114, and strains of Bacillus coacillus revealed a significantly intensive inhibitory activity in the linoleic acid peroxidation reactions. Spearmans' rank correlation between inhibitory activity on linoleic acid peroxidation and cellular GSH levels of Lactobacillus spp. was analysed and the correlation quotient was 0.65 which means a significant positive correlation.

• Journal of Dairy Science and Biotechnology
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• v.16 no.2
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• pp.83-89
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• 1998

Studies on the antimutagenicity of Lactobacillus spp. and Bifidobactrium spp. against 2-nitrofluorene have been conducted utilyzing Salmonella typhimurium TA 98 in order to characterize the activity by the starter and non-starter strains. The average antimutagenic activity of Lactobacillus spp. and Bifidobactrium spp. against 2-nitrofluorene was 20.29% and L. plantarum CU 722 revealed the greatest mutation inhibition activity of 50.34%. An intensive antimutagenicity was found in the cell wall and cytoplasm fraction of L. plantarum CU 722 in skim milk culture showing inhibition rate of 34.9% and 24.5% respectively and very low activity remained in cell free broth and in lactic acid. The optimum cultivation time for Lactobacillus spp. and Bifidobacterium spp. to inhibit mutation was 24 hours and the optimum preincubation time of the reaction mixture containing the mutagen, lactic culture and indicator strain was 60 minutes, and the optimum incubation time for the test plates was 48 hours.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.119-126
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• 1991

ABSTRACT - This study was performed to investigate the possible effect of Lactobacillus spp. on the growth and citrinin production by Penicillium citrinum. Lactobacillus bulgaricus and Lactobacillus casei were grown with Pen. citrinum in modified APT broth containing 7% of glucose and incubated at $30^{\circ}C$ for 15 days. Four inoculation procedures were used; (a) Lactobacillus spp. and Pen. citrinum were grown alone(Pc, Lb, and Lc), (b) both organisms were added simultaneously(ST; Pc+Lb and Pc+Lc), (c) Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc), and (d) Pen. citrinum was grown 3 days, then Lactbacillus spp. was added (PcLb and PcLc). At 0, 3, 6, 9, 12, 15 days of incubation, the growth of each organism, pH and total acidity of broth, and content of citrinin were determined. Lactobacillus spp. and Pen. citrinum, when grown associatively, influenced the growth of each other. It was observed that slower growth of Pen. citrinum when in the presence of Lactobacillus spp. than when the mold grew alone. Production of citrinin by Pen. citrinum was markedly less in the mixed culture. No apparent growth and toxin production was observed when the Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc). The above results indicate that another microorganism or competing microflora in the culture can affect the behavior of Pen. citrinum.trinum.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.2
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• pp.59-64
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• 2015

Lactic acid-producing bacteria such as Lactobacillus spp. function to ferment carbohydrates and produce ATP. Such Lactobacillus spp. are used for the production of commercial yogurts. Lactobacillus spp. are beneficial to the intestinal tract, and Lactobacillus acidophilus-containing yogurts have received considerable attention because of their preventive effects against early-stage cancer of the large intestine. In this study, lactic acid-producing bacteria were cultured from three different groups: commercial solid yogurt (for eating), commercial liquid yogurt (for drinking), and Lactobacillus acidophilus-containing yogurt. We first determined the optimum culture conditions for Lactobacillus spp. and then analyzed turbidity and pH in order to compare the growth abilities and lactic acid-production capacities among the groups. Finally, high-performance liquid chromatography was used to measure the lactic acid content in the culture supernatants, and the antibacterial activities against Staphylococcus aureus and Escherichia coli were compared among the three groups. The optimum culture conditions for Lactobacillus spp. were MRS medium at $25^{\circ}C$, for 24 h. The highest turbidity was found in L. acidophilus-containing yogurt, followed by liquid yogurt and solid yogurt. Similarly, the highest lactic acid production ability was found in L. acidophilus-containing yogurt, followed by liquid yogurt and solid yogurt. Culture supernatants from the three groups did not show any antibacterial activity towards S. aureus; however, supernatants derived from L. acidophilus-containing yogurt resulted in a 1.8 mm inhibitory zone against E. coli in a paper disk diffusion test. These results revealed the high level of lactic acid-production capacity and antibacterial activity in L. acidophilus-containing yogurt.

• Journal of Dairy Science and Biotechnology
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• v.22 no.2
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• pp.107-112
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• 2004

Studies on the resistance of Lactobacillus ssp., Bifidobacterium spp. and Bacillus coagulans to hydrogen peroxide were conducted by determination of the viable cells after the test cells in 2mM hydrogen peroxide solution for a predetermined time; L. acidophilus CU4111 and L. casei CU4114 were most resistant to the hydrogen peroxide among the fifteen test lactobacilli strains, whereas L. brevis Cu4206 was the strain which was the most susceptible to hydrogen peroxide. Bifidobacterium longum Cu4131 was one of the resistant strains. A prominant tendency found out that Bacillus coagulans possessed a strong resistance to hydrogen peroxide. The results of level of hydrogen peroxide determination in the cell extracts showed all the test strains contained hydrogen peroxide in the cytoplasm, the amount varied depending on the strain and species of lactic acid bacteria. Bifidobacterium bifidum CU 4134 and L. casei CU 4114 were potent hydrogen peroxide producer strain.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.473-482
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• 2003

In vivo protective and in vitro inhibitory activities of Lactobacillus casei YIT 9018. against typical enteritis causing Salmonella enteritidis KU101 and IgA level after challenge have been determined. In order to identify the strains of lactobacilli the sequences of 16S-23S rRNA intergenic spacer region were determined. All the test strains of Lactobacillus spp. inhibited Salmonella enteritidis, the intensity varied depending upon the species of lactobacilli. Effects on the survival rate of the mouse after challenge with Salmonella enteritidis KU101 on feeding Lactobacillus spp. have shown the highest survival rate in L. helveticus CU 631 followed by L. casei YIT 9018 and L. johnsonii C-4 and the lowest in control mice. The higher level of total Ig A concentration in the intestinal fluid of lactobacilli fed mice than control mice was observed. The sequences of 16S-23S rRNA intergenic spacer region of seven strains of Lactobacillus casei could be utilized as a strain identification, those sequences showed some degree of difference in homology.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.854-858
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• 2005

A Lactobacillus isolate was collected from the feces of a healthy Korean individual and named as Lactobacillus ruminus SPM0211. It was further characterized by subjecting it to an antibiotic resistance test and genetic analysis. In the antibiotic resistance test, all tested Lactobacillus spp. were classified as 'high resistance' for multiple antibiotics, such as isoniazid, ethambutol, cycloserine, and vancomycin. L. ruminus SPM0211 was classified as 'high resistance' for streptomycin also, while the other tested Lactobacillus spp. were classified as low resistance. This suggests that the antimicrobial spectra may be a good indicator in the discrimination of this strain among the tested Lactobacillus spp. In a polymerase chain reaction-random amplified polymorphic DNA (PCR-RAPD) analysis using the Microbial Uniprimer kit, L. ruminus SPM0211, and L. suebicus were clustered as a group with a 74.3% similarity level, suggesting that these two species are genetically related. Thus, our data suggest that the PCR-RADP method using the Microbial Uniprimer kit may be valuable in discriminating L. ruminus SPM0211 from other Lactobacillus spp.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1582-1585
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• 2004

The antioxidative ability on the basis of reduced glutathione sulphydryl level, the inhibition activities of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and the effects of types of media and growth phase of the cells on the cellular GSH level have been determined. Correlation between reduced glutathione sulphydryl level and antioxidative ability of Lactobacillus spp. was analyzed: Lactobacillus casei HY 2782 contained 25.15 $\mu$mole/g of GSH, the cellular GSH level of L. casei HY 2782 reached maximum after 24 h of cultivation and tended to decrease on further cultivation up to 72 h. There was a significantly higher level of cellular GSH when grown in de Man Rogosa and Sharpe (MRS) broth than in tryptone phytone yeast extract (TPY) broth or bromcresol pruple dextrose (BCP) broth (p<0.05). The antioxidant activity of cell free extract of Lactobacillus spp. have been shown to be significantly different among strains in the inhibition of linoleic acid peroxidation by thiobarbituric acid (TBA) test (p<0.01). L. casei HY 2782 and L. acidophilus ATCC 4356 revealed a high degree of antioxidative effect in linoleic acid oxidation system. Spearmans' rank correlation coefficient between inhibitory activity on linoleic acid peroxidation and cellular GSH levels of Lactobacillus spp. was 0.65, which means a significant positive correlation.

• KSBB Journal
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• v.17 no.3
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• pp.311-313
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• 2002

Lactobacillus spry. are Gram-positive bacteria playing important roles in human health. In this study, we successfully isolated the total RNA from the cells broken by glass beads using hot phenol method. Moreover, we were able to omit lysozyme and proteinase K treatment by using glass beads to break cell more efficiently. This method was more rapid and simple when compared to the previous one. Prepared RNA can be used for the transcriptional analysis of Lactobacillus spp.