• Journal of Dairy Science and Biotechnology
• /
• v.15 no.1
• /
• pp.11-20
• /
• 1997

This study was designed to carry out an observation on the growth inhibitory effect of fermented milk by the the lactic acid bacteria such as Lactobacillus bulgaricus, L. acidophilus and L. cormatus against pathogenic Escherichia coli O157:H7 were studied in vitro. The results of this study were as follows : The BL broth culture of L. bulgaricus, L. acidophilus and L. cormatus gave a similar extent of growth inhibitory effects against the pathogenic E. coli O157:H7 were after incubation time within 18 hours. The inhibitory effects of the fermented milk were observed on the survival time of pathogenic E. coli O167:H7 in the various fermented milk at 37${\circ}$C shaking water bath (70 rpm) were after incubation time between 140 and 200 minutes. These results indicated that major portion of growth inhibitory effects of fermented milk with various lactic acid bacteria against pathogenic E. coli O157:H7 was possible due to the acid, and minor portion to the other antibacterial substances.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.3
• /
• pp.439-443
• /
• 2001

The effect of fermentation of peanut milk with lactic acid bacteria on n-hexanal content was investigated. Changes in pH, titratable acidity and viable cell populations indicated that Streptococcus salivarius subsp. thermophilus was adapted better than Lactobacillus delbrueckii subsp. bulgaricus during fermentation. Analysis of headspace volatiles revealed that n-hexanal, which is one of the compounds responsible for undesirable green/beany flavor in peanut milk, completely disappeared as a result of fermentation. S. salivarius subsp. thermophilus was more effective than L. delbrueckii subsp,. bulgaricus in reducing the n-hexanal content. No significant difference was found in water sorption between fermented and unfermented peanut milk.

• The Korean Journal of Food And Nutrition
• /
• v.26 no.1
• /
• pp.146-149
• /
• 2013

This study was performed to identify the effect of lactic-fermentation of peanut milk on n-hexanal content. Changes in viable cell populations, pH and titratable acidity indicated that there was a synergistic interaction between Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus during fermentation. The analysis of headspace volatiles revealed that n-hexanal nearly disappeared due to fermentation. S. salivarius subsp. thermophilus was more effective than L. delbrueckii subsp. bulgaricus in reducing the n-hexanal content.

• Microbiology and Biotechnology Letters
• /
• v.10 no.1
• /
• pp.9-14
• /
• 1982

Three common species of lactic acid bacteria, Lactobacillus casei, Lactobacillus bulgaricus, and Streptococus lartis were tried to store in frozen state for various periods up to four months and their stabilities during the storage were evaluated. A needle of culture suspension was transferred to 10 $m\ell$ of 10% reconstituted skim milk and frozen immediately. After storage under said conditions the storage tubes were thawed and incubated under optimum growth temperatures for 48 hours after which plate counts and acidity determinations were made. The same incubation and analyses were repeated with organisms transferred from the previous culture tubes. No significant deterioration in both survival and acid producing activity were observed during the four month storage except that some decrease in acid forming by L. bulgaricus appeared after 60 days of storage. Among the three species tested L. casei was found to be most stable and the fast was reconfirmed with scale-upped fermentation experiments using the same organism.

• Microbiology and Biotechnology Letters
• /
• v.27 no.5
• /
• pp.385-390
• /
• 1999

To investigate bile salt hydrolase activities of the bacterial strains isolated from fermented milk products, 21 strains of Lactobacillus were tested for their abilities to produced cholic acid from taurocholic and glycocholic acids. The production of cholic acid was measured by HPLC analysis during the growth in broth media for 24hrs. All strains of Lactobacillus acidophilus and L. plantarum deconjugated both taurocholate and glycocholate, whereas none strains of L. delbrueckii subsp. bulgaricus, L. casei subsp. casei, L. casei subsp. rhamnosus, L, reuteri did. L. acidophilus stains isolated from yogurts had the higher decojugation activities on glycocholate than taurocholate, however, L. acidophilus 1009 isolated from the human intestine showed the similar deconjugation activities on both taurocholate and glycocholate.

• Food Science of Animal Resources
• /
• v.25 no.4
• /
• pp.483-493
• /
• 2005

This experiment was carried out to examine the fermentation properties of yogurt prepared with bovine milk and soybean milk at the mixed ratios of 3:1, 2:1, 1:1, 1:2 and 1:3. The effect of bovine milk and soybean milk on promoting the fermentation was higher un pH was $3.75\~4.16$ when Lactobacillus salivarius ssp. salivarius CNU27, lactic culture 1(Lactobacillus delbrueckii ssp. bulgaricus(LB12)), Streptococcus salivarius ssp. thermophilus (ST36) and Lactobacillus acidophilus KCTC3150 were used. Titratable acidity was the highest when lactic culture 1[Lactobacillus delbrueckii ssp. bulgaricus(LB12), Streptococcus salivarius ssp. thermophilus(ST36)] was mea and the mixed ratio of bovine milk and soybean milk was 2:1. The average viable counts of lactic acid bacteria was the highest level of $2.17\times10^9$ cfu/ml when Lactobacillus salivarius ssp. salivarius CNU27 was used, and the mixed ratio of bovine milk and soybean milk was 1:3. the highest lactic acid production was 412.52mM when lactic culture 1[Lactobacillus delbrueckii ssp. bulgaricus (LB12), Streptococcus salivarius ssp. thermophilus (ST36)] was used, and the mixed ratio of bovine milk and soybean milk was 1:1. The production of acetic acid was the highest and the concentration was 394.01mM when lactic culture 2(Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus salivarius ssp. thermophilus) was used and the mixed ratio of bovine milk and soy bean milk was 3:1. Tn the carbohydrate hydrolysis, stachyose was hydrolyzed $53.92\%$ as compared with the control when Lactobacillus salivarius subsp salivarius CNU27 was used, and the mixed ratio of bovine milk and soy bean milk was 1:3. The highest viscosity of yogurt was $1,300\~1,660$ cP when the mixed ratio of bovine milk and soybean milk was 1:3. The overall acceptability, $4.17\pm0.69$, was the highest when Lactobacillus acidophilus KCTC3150 was used and when the mixed ratio of bovine milk and soybean milk was 2:1.

• Journal of Food Hygiene and Safety
• /
• v.16 no.4
• /
• pp.264-273
• /
• 2001

Antimicrobial activities of ave different probiotics (Lactobacillus reuteri, L. acidophillus, L. bulgaricus, L. casei and Bifidobacterium longum) against 8 bacterial pathogens were determined on the Mueller Hinton Agar containing supernatant of probiotics obtained from 3 different growth conditions (MRS without glycerol, MRS with 0.5 M glycerol or 0.25 M glycerol solution). Though antimicrobial activity of L. reuteri in the first two conditions was not better than the others', the activity was significantly higher than that of others in 0.25 M glycerol solution. This prominent effect might be attributable to reuterin, produced by L. reuteri using glycerol. We could detect the presence of reuterin in the supernatant of 0.25 M glycerol solution with 500 MHz Nuclear Magnetic Resonance (NMR). The result of minimum bactericidal concentration (dilution fold) has revealed that reuterin showed pan-bactericidal effects against 8 major food-borne pathogens. To examine any changes of antimicrobial activities of the probiotics, the probiotics were treated with different pH conditions, pepsin or trypsin digestion. Antimicrobial activity of reuterin was not entirely affected by any of these treatments, while the activities of the other probiotics were significantly decreased.

• YAKHAK HOEJI
• /
• v.29 no.3
• /
• pp.159-164
• /
• 1985

To investigate the susceptibility and resistance in case of simultaneous administrations of Lactobacilli and Clostridia prekparations with antituberculosis agents and antibiotics, five strains of Lactobacilli, i.e., Lactobacillus bulgaricus, L. casei, L. helveticus, L. acidophilus, L. sporogenes, and Clostridium butyricum were isolated from commercially available preparation. Minimal inhibitory concentrations (MIC) of nine antituberculosis agents and 21 antibiotics against these strains were determined. The results shwoed that these strains were very sensitive only to rifampicin among antituberculosis agents, and sensitive to other antibiotics. Since the simultaneous oral administration of rifampicin and other antibkiotics with these sensitive strains is ineffective, development of new resistant mutants is desirable.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 1976.10a
• /
• pp.187.3-187
• /
• 1976

건조 유산균 starter (Lyophillized lactic sarter) 제조 과정 중 동결건조에 의한 viability의 저하를 방지하는 방법의 하나로서 유산균을 농축 (concentrate) 시켰다. 유산균을 농축시키기에 앞서 cell의 농도를 높여줄 필요가 있었으므로 Cell의 증식에 영향을 미치는 요인으로 agitation 및 aeration을 채택하여 그것이 cell의 증식 및 lactic acid producing ability에 미치는 영향을 조사한 결과 다음과 같은 사실을 알 수 있었다.(중략)

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.30 no.1
• /
• pp.1-7
• /
• 1997

In order to utilize fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures Lactobacillus buigaricus KCTC 3188 and L. piantarum KCTC 1048 were used as a starter culture for the preparation of fermented fish silage with skipjark tuna viscera. The optimum temperature and pH on barterial growth and lactic acid production of L. bulgaricus and L. plantarum in MRS broth were $35^{\circ}C$ and around pH 6.0, respectively. And the optimum concentrations of the carbohydrate sources added to the broths were $7\%$ for dextrose and $10\%$ for molasses on the basis of total weights of skipjack tuna viscera. The pH of acid treated skipjack tuna viscera silage (ASS) slightly increased from 4.0 to 4.5, while that of fermented skipjack tuna viscera silages by the use of lactic acid bacterias (FSS) was significantly declined from 5.9 to about 40 after 42 days of storage at $35^{\circ}C$. Though the content of volatile basie nitrogen (VBN) in ASS was lower than those of FSS after 42 days of storage at $35^{\circ}C$, VBN content in silages slightly increased from an initial value of $62\~65{\cdot}mg/100g$ to final value of $113\~155\;mg/100g$ over 42 days. The fermented silage by L. piantarum reached a maximum concentration of amino nitrogen and showed $81\%$ of hydrolysis degree after 4 days of storage at $35^{\circ}C$.