• Korean Journal of Microbiology
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• v.48 no.1
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• pp.29-36
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• 2012

This study was conducted to investigate antioxidative and physiological activities of two stage fermented Chinese Yam (TSFCY) by Monascus sp. MK2 and Lactobacillus brevis HLJ59. The extracts from TSFCY were measured to examine pigments, monacolin K contents, total polyphenol and flavonoid contents, DPPH radical scavenging activity, reducing power, ACE inhibitory activity and GABA contents. In this study, the results show that Monascus sp. MK2 and Lactobacillus brevis HLJ59, with Dioscorea batatas Dence. As the substrate can produce pigments (yellow, orange and red), monacolin K contents, total polyphenol and flavonoid contents, DPPH radical scavenging activity, reducing power, ACE inhibitory activity, and GABA contents at 14.03 (yellow), 13.88 (orange), 15.71 (red), 487.9 (MK, mg/kg), 723.8 (TP, mg/kg), 326.4 (TF, mg/kg), 81.7 (DPPH, %), and 1.5 (RP, O.D), respectively. In addition, the showed ACE inhibitory activity and GABA contents was 86.9% and 977.4 mg/kg in EtOH extract, respectively.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.56-61
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• 2003

The purpose of the present study was to screen the effective of lactic acid bacteria (LAB), as probiotics which are able to protect bacterial fish diseases and investigate their characteristics. Twenty strains of lactic acid bacteria were isolated from fish intestine. fermented fish foods and kimchis. These bacteria were screened for antagonistic activity against fish pathogenic bacteria. Seven tested LAB strains were able to inhibit the fish pathogenic bacteria, including Vibrio anguillarum, Edwardsiella tarda and Streptococcus sp. Of the probiotic candidates, BK19 strain which from fermented pollack viscera indicated the largest inhibition activity. This particular probiotic bacteria was identified and named as Lactobacillus sakei BK19. In the scanning electron microscope observation, L. sakei BK19 supernatant treated V.anguillarum cell wall had been destroyed incubate after 3 hr.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.86-91
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• 2004

Changes in erotic acid (OA) contents of raw milk and during cultivation and storage at refrigerated temperature were determined. OA contents of raw and 10% reconstituted milk held at $121^{\circ}C$ for up to 15 min decreased by 17.6 and 22.4%, and those fermented at 40 and $37^{\circ}C$ for 72 hr with Lactobacillus helveticus 166 and Lactobacillus casei 955 decreased 37.8-43.2 and 41.8-76%, whereas when fermented at $40^{\circ}C$ for 72 hr with Streptococcus thermophilus ST-37, did not decrease significantly compared with fermentation by other lactobacilli. OA content did not change during storage at refrigeration temperature. OA reduction by Lactobacillus sp. was dramatically increased at the initiation of stationary phase during fermentation. OA reduction varied among different lactobacilli. These results show decrease in cultivation time, rapid cooling of yogurt, and proper selection of Lactobacillus sp. prevent OA content reduction.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.345-349
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• 1992

Thymidylate synthase activity from extracts of various methotrexate-resistant strains was measured by spectrophotometric assay. Methotrexate-resistant strains of Lactobacillus, Pseudomonas sp., Micrococcus sp. HS-1, Klebsillela pneumonae, Cellulomonas fimi and Serratia marcescens elevated thymidylate synthase levels, especially, Pseudomonas sp. KL-9 resistant to $10^{-9}M$ methotrexate have a 156-fold increase in thymidylate synthase, which suggests that Pseudomonas sp. is a convenient source of thymidylate synthase. Several methotrexate strains of yeast were tested, however, their enzyme activity was generally lower than that of bacteria tested.

• Microbiology and Biotechnology Letters
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• v.24 no.3
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• pp.299-303
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• 1996

Isolation, identification, and culture conditions of a lytic enzyme producing microorganism against Lacto- bacillus plantarum were investigated. The selected strain was gram-positive, rod (0.7 $\times$ 2.7 $\mu$m in size), and non-motile. The strain did not have any flagella and spores. According to its cultural and physiological characteristics, the strain was identified as Bacillus sp. The optimal pH and temperature for the production of lytic enzyme were 8.0 and 30$\circ$C, respectively. The maximum enzyme activity showed 1.5 units/ml in the medium composed of 1% peptone and 0.1% NaCl.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.43-49
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• 1988

Fermented barley food was produced by the combining action of an enzyme and a lactobacillus. When Lactobacillus sp. L-5 and commercial liquefying amylase from Tae Pyeong Yang Chemical Co. were selected, inoculated on steamed barley and cultivated at 37$^{\circ}C$ for 48hrs, the fermented product of good quality was obtained. In batch cultivation using rotary drum fermentor, viable cell count reached 1.1$\times$10CFU/g after 12hrs' cultivation, and specific growth rate in logarithmic phase was 0.6hr-1. Viable cell count, acidity, pH, concentration of reducing sugar and viscosity of the 48hrs' fermentation product from rotary drum fermentor was 4.3$\times$108CFU/g, 1.17%, 3.1, 10.7% and 1430cp.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.540-546
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• 1999

The purpose of this study was to investigate the antimicrobial effects and characteristics of protamine extracted from spermary of tuna. The result of amino acids analysis showed that the contents of arginine were 46%. It was 10% lower when compared to standard protamine (SP: Asama kasei LTD, Japan). Also, there were significant difference in the contents of proline adn glycine. The average molecular weights of main protein in TP were 13,400 Da, whereas those in SP were 11,300 Da and 2,600 Da. To increase antimicrobial activities of TP, pepsin or trypsin was treated at $37^{\circ}C$. After TP was hydrolyzed with pepsin (pepsin hydrolyzed protamine: PHP) for 4hrs, the average molecular weights of the main protein were 11,300 Da and 3,900 Da, and the antimicrobial activities were significantly increased compared to TP. After TP was hydrolyzed with trypsin (trypsin hydrolyzed protamine: THP) for more than 10 min, the average molecular weights of the main protein were below 2,500 Da. PHP had higher antimicrobial effects on some gram positive bacteria (Staphylococcus aureus, Lactobacillus helveticus, Lactobacillus plantarum) than SP. However, THP had no antimicrobial activities. When TP was hydrolyzed with pepsin (PHP), its antimicrobial activities increased in the same level with those of SP, and this increase might be resulted rather from the changes of molecular weights of the main protein than from the contents of arginine in protamine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.971-976
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• 2002

Effect of storage temperature and packing method on the changes in pH, acidity, the levels of lactic acid bacteria, volume expansion of packages and the colorness during the fermentation of kakdugi (diced radish kimchi) were investigated. The fermentation characteristics were greatly influenced by the temperature. The pH of kakdugi fermented at 15$^{\circ}C$ was 4.10 at 3 days, while the pH of kakdugi fermented at $0^{\circ}C$ was 4.03 at 18 days. The acidity of kakdugi fermented at $0^{\circ}C$ very slowly increased compared to that of the kakdugi fermented at 15$^{\circ}C$, 1$0^{\circ}C$ or 5$^{\circ}C$. The required days to reach the acidity of 0.6% (optimally ripened state) were 6 days at 15$^{\circ}C$, 7 days at 1$0^{\circ}C$, 18 days at 5$^{\circ}C$ and 30 days at $0^{\circ}C$. Despite of different fermentation temperature, the numbers of Leuconostoc sp. in optimally ripened kakdugi were similar. However, Lactobacillus sp. in kakdugi fermented at $0^{\circ}C$ was the smallest in number. Also, the volume expansion of aluminum pack was the lowest in kakdugi fermented at $0^{\circ}C$. Both pH and acidity of the kakdugi fermented in different packing condition did not show any difference at 1$0^{\circ}C$ for 20 days, however, the color of the kakdugi was affected by a packing method. Aluminium laminate package in which Ca(OH)$_2$ Pack stuck inside resulted in decolorization of kakdugi compared with aluminum package without Ca(OH)$_2$ pack or plastic jar. It showed the lowest redness and the highest lightness and yellowness. These results indicated that fermentation at $0^{\circ}C$ could increase storage period of kakdugi with minimum growth of Lactobacillus sp., and plastic jar might relieve the problem of volume expansion and decolorization of kakdugi.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.88-98
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• 2016

The pharmacological effects of ginseng berry have been known to improve psychological function, immune activities, cardiovascular conditions, and certain cancers. It is also known that fermentation improves the bioavailability of human beneficial natural materials. Accordingly, we investigated the optimal fermentation conditions of ginseng berry extract with strain isolated from conventional foods. We also analyzed the fermentation product and its antioxidant activity. The bacterium isolated from fermented kimchi was identified as Lactobacillus sp. strain KYH. To optimize the process, fermentation was performed in a 5 L fermenter containing 3 L of ginseng berry extract at 200 rpm for 72 hr. Under optimized conditions, batch and fed-batch fermentations were performed. After fermentation, organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were evaluated. The optimum fermentation conditions were determined as pH 7.0 and a temperature of $30^{\circ}C$, respectively. After fermentation, the amounts and compositions of organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were altered. In comparing the distribution of ginsenosides with that before fermentation, the ginsenoside Re was a major product. However, amounts of ginsenosides Rb1, Rc, and Rd were reduced, whereas amounts of ginsenosides Rh1 and Rh2 increased. Total phenol content increased to 43.8%, whereas flavonoid content decreased to 19.8%. The DPPH radical scavenging activity and total antioxidant activity increased to 27.2 and 19.4%, respectively.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.104-108
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• 2006

Water extracts of Jehotang were evaluated for their growth-promoting effects on Bifidobacterium longum, Lactobacillus sp., L. acidophilus, and Clostridium perfringens. Addition of Jehotang water extract to modified EG media at 0.1 mg/mL increased growths of B. longum, Lactobacillus sp., and L. acidophilus, with 1.8-fold increase in growth of L. acidophilus compared to that of control. Studies on these strains by agar diffusion method showed Lactobacillus sp. and L. acidophilus were activated by addition of Jehotang extract at 10 mg/disc. Proliferation responses of mice splenocytes and Peyer's patch cells to ConA by LPS-stimulation at 500 mg/kg B.W./day Jehotang extract were investigated in vitro. Upon treatment of 1 mg/mL Jehotang water extract to mice, proliferations of splenocytes and Peyer's patch cells increased 1.4- and 1.6-fold compared to control, respectively. In mice administered Jehotang extract, production of intestinal secretory IgA (sIgA) increased 2.4-fold compared to control. These results indicate water extract of Jehotang stimulated intestinal immune system of mice. In mice treated with Jehotang extract, production of lymphocytes was 4% lower, whereas those of granulocytes and platelets were 4% and slightly higher than control, respectively.