• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.296-303
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• 2005

A strain named as HJ35 was isolated from the skin of sixty-five men and fourteen women for acne therapy, in order to find an effective antimicrobial agent against Propionibacterium acnes. Isolate HJ35 was identified as Enterococcus faecium based on 16 rDNA sequence and produced enterocin HJ35 having antimicrobial activities against most lactic acid bacteria, En­terococcus spp., Staphylococcus aureus, S. epidermidis, Clostridium perfringens, some bacilli, Mi­crococcus flavus, Listeria monocytogenes, L. ivanovii, Escherichia coli, Pseudomonas fluorescens and Propionibacterium acnes, in the modified well diffusion method. Especially, enterocin HJ35 showed a bactericidal activity against Propionibacterium acnes P1. The antimicrobial activity of enterocin HJ35 was disappeared completely with the use of protease XIV. But enterocin HJ35 activity is very stable at high temperature (up to $100^{\circ}C$ for 30 min), in wide range of pH (3.0${\~}$9.0), and by treatment with organic solvents. The apparent molecular mass of enterocin HJ35 was estimated to be approximately 4${\~}$4.5 kDa on detection of its bactericidal activity after SDS-PAGE. In batch fermentation of E. faecium HJ35, enterocin HJ35 was produced at the mid­log growth phase, and its maximum production was obtained up to 2,300 AU/mL at the late stationary phase. By employing fed-batch fermentation, the enhanced production of enterocin HJ35 was achieved up to 12,800 AU/mL by feeding with 10 g/L glucose or 6 g/L lactate.

• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.1-8
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• 2018

Gul (oyster) jeotgals (GJs) were prepared using different types of salt (23%, w/v): purified salt, solar salt aged for 3 years, and bamboo salt crystalized 3 times. One set of GJs was fermented with Bacillus subtilis JS2 ($10^6CFU/g$), while the other GJ set was fermented without starter. During fermentation for 24 weeks at $15^{\circ}C$, the starter GJs showed 10-fold higher bacilli counts than the no-starter GJs, where the maximum bacilli count was $8{\times}10^3CFU/g$. All 28 bacilli strains isolated from the 6-week GJs were identified as B. subtilis by using a RAPD-PCR, indicating that some of the B. subtilis JS2 cells remained viable. Lactic acid bacteria (LAB) and yeasts were present at low levels, $10^1-10^2CFU/g$. LAB with protease activities isolated from 10-week samples were identified as Enterococcus species. The isolates obtained at 16 weeks were all Staphylococcus species. The GJs with bamboo salt showed higher pH and lower titratable acidity (TA) values than the other GJs due to the strong alkalinity of bamboo salt. The amino-type nitrogen in the GJs increased slowly during the fermentation. At 24 weeks, the GJs with purified salt showed the highest amino-type nitrogen (412-430 mg%), followed by the GJs with solar salt (397-406 mg%) and GJs with bamboo salt (264-276 mg%). Meanwhile, the GJs with bamboo salt showed the highest ammonia-type N (63.67 mg%), followed by the GJs with purified salt (49 mg%) and solar salt (48 mg%).

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1243-1249
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• 2011

This study was performed to examine the use of NaOCl as an alternative antimicrobial compound in winemaking because of the potential health problems that may arise as a result of the use of $SO_2$. For this, the blank (non-treated), control ($SO_2$-added), and sample (NaOCl-treated) wines were made, and microbial and chemical changes including sensory characteristics were analyzed during the fermentation periods. Treatment of grapes with NaOCl decreased the initial contaminating microbial population in grape must, resulting in higher growth of yeast and lactic acid bacteria. After 200 days of fermentation, the chemical analysis of sample wine revealed that it had higher ethanol content, redness ($a^*$), and concentrations of fruity ester compounds and lower total acidity than the control. In the sensory analyses, the sample wine obtained a higher overall acceptability score (5.70) than the control (4.26). This result reveals that NaOCl can be used as an alternative to $SO_2$ in winemaking for inhibiting the growth of contaminating microorganisms.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1149-1155
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• 2020

Silage is one of the main feed components of ruminants around the world and can make up about 50-80% of the rations of dairy cows during the winter. The aim of this study was to evaluate the usability of oregano (Origanum vulgare L.) and thyme (Thymus vulgaris L.) aqueous and ethanol extracts to improve the hygienic quality of perennial ryegrass, red clover and blue alfalfa silage samples and estimate their effect on mycotoxins concentrations. Under laboratory conditions, 63 silage samples (21 perennial ryegrass, 21 blue alfalfa, 21 red clover) were fermented with inserted aqueous and ethanol extracts of oregano and thyme and two commercial inoculants with mesophilic lactic acid bacteria. After 96 days of fermentation, in silage samples were established fermentation parameters, microbiological status and mycotoxins concentrations. It was determined that the best results for achieving hygienic quality of perennial ryegrass and red clover silage samples was by insertion of aqueous and ethanol extracts of oregano and thyme. In blue alfalfa samples, the best results of silage hygienic indicators were determined by inserting aqueous and ethanol extracts of oregano. Aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEA) and T-2 toxin concentrations in perennial ryegrass, red clover and blue alfalfa silage samples were best reduced by inserting aqueous and ethanol extracts of oregano and thyme. The present study shows that these extracts can be used to improve silage hygienic quality, reduce mycotoxins concentrations and thus ensure the wellness of cattle.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.27-36
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• 2013

This study was conducted to develop and characterize sea squirt Halocynthia roretzi sikhae. According to the results for pH, total acidity, lactic acid bacteria, amino nitrogen and sensory evaluation of sea squirt sikhae during fermentation for 6 days at $15^{\circ}C$, the optimum fermentation periods were 4 days for sourness-disliking customers and 5 days for sour-disliking customers. No differences in the proximate compositions of sea squirt sikhaes fermented for 4 days (4D) and for 5 days (5D) were found. There was a difference in the eproximate compositions of commercial seasoned sea squirts, 4D and 5D, sea squirt sikhaes. The results of salinity, total acidity, amino nitrogen and sensory evaluation of two kinds of sikhae suggest that the taste was stronger for 5D than for 4D, both of which were superior to commercial seasoned sea squirts. There was, however, no difference in color of 4D, 5D and commercial seasoned sea squirts. The results of E. coli analyses suggest that sea squirt sikhae is a safe food in terms of sanitation.

• Preventive Nutrition and Food Science
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• v.5 no.4
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• pp.189-193
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• 2000

Preservative and antimutagenic effects of green tea leaves added Chinese cabbage kimchi (GK1, GK2, GK3, and GK4 : 1, 2, 3 and 4 of green tea leaves (GTL) in proportion of 100 of salted Chinese cabbage were added to kimchi) were compared to those of the Chinese cabbage kimchi without GTL (control kimchi, CK). Fermentation period of GKs was further delayed than that of CK. The initial pH and acidity between GKs an CK were similar, but the time reach optimally ripened status of kimchi (pH 4.3) was different. CK took 6 days, while GK1, GK2, GK3 and GK4 took 6, 10, 12 and 14 days at 10℃, respectively. The growth of Leuconostoc sp. and Lactobacilus sp. in GKs delayed comparing to those in FCK. Among GKs, as the added amount of green tea leaves increased, the growth of lactic acid bacteria was retarded. The antimutagenic effects of juices from GKs and CK were studied against aflatoxin B₁(AFB₁) in the Ames test on Salmonella typehimurium TA100 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the SOS chromotest using E. coli PQ37. Juices from optimally ripened GKs (pH 4.3) showed 52∼76% inhibition rates against the indirect mutagen, aflatoxin B₁ induced mutagenicity while 49% inhibition rate by CK in the Ames test. Juices from GKs and CK showed 44∼67% and 36% inhibition rate against direct mutagen, MNNG (70 ng/assay) induce mutagenicity in the SOS chromotest. Thus GKs delayed fermentation period of kimchi and exhibited higher antimutagenic activity than CK.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.188-197
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• 2010

In this study, the quality characteristics and storage properties of gat kimchi added with oyster shell powder and Salicornia herbacea powder were investigated during a storage time of 80 days at $5^{\circ}C$. After storage for 80 days, the average calcium contents were significantly higher in the kimchi containing the oyster shell powder and Salicornia herbacea powder than the control. In addition, the average hardness value was significantly higher in the OS4 group(oyster shell powder at 4% and Salicornia herbacea powder at 2%) than the control group, as well as the OS10 group(oyster shell powder at 10% and Salicornia herbacea powder at 2%) during storage for 80 days. The hunter b value of the OS4 group was significantly lower than the control group. During fermentation, gat kimchi containing the oyster shell powder and Salicornia herbacea powder had a higher pH and a lower acidity value than the control group. In terms of sensory evaluation, there were no significant differences between the control and calcium-added kimchi during fermentation. After 40 days of storage, the OS4 group showed a lower total viable count, as well as lower lactic acid bacteria, yeast and E. coli, as compared with the control and OS10 groups. Based on the microbial load, the gat kimchi containing the oyster shell powder showed limitations in terms of shelf life.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.249-254
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• 2011

Applying ginger to processed foods to improve health is limited due to its pungent odor. In this study, fermented gingers were prepared using lactic acid bacteria from dairy products or kimchi and their chemical and sensory properties were examined. Adding dried ginger or fermented gingers (GSt, GLa, GLm) to plain yogurt made them less tasty and lowered the overall acceptability of yogurt except GLp. For all fermented gingers including GLp, the characteristic flavors of the ginger decreased by fermentation so adding fermented ginger into yogurt did not affect its flavor significantly. Thus GLp would be expected to be a food ingredient instead of dried ginger without lowering organoleptic qualities. The content of 6-gingerol, a bioactive component in ginger, decreased in all fermented gingers. However, 6-shogaol, which increased in GSt, GLa, and GLm, was not detected in GLp.

• Food Science and Preservation
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• v.9 no.2
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• pp.200-204
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• 2002

This study was carried out to investigate the effect of safflower powder on the characteristics of kimchi. Quality indexes were pH, titratable acidity, reducing sugar content, microbial counts, and sensory evaluation. Safflower powder enhanced the decrease in pH and increase in titratable acidity during fermentation at l0$^{\circ}C$, and the changes were more conspicuous until 15 days. Stabilized levels in pH was attained, but steady increase in titratable acidity was shown after that time. Microbial loads of total and lactic acid bacteria showed a faster stationary phase for kimchi samples with safflower powder than control. Control was better scores in sensory evaluation, but there were no significant differences in aroma and taste except sample with 3% safflower powder.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.259-265
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• 2011

Through the process of fermentation with Lactobacillus strains this study has evaluated the functionality of the traditional Korean medicine Bangpungtongsungsan after the addition of four other medicinal ingredients. In order to facilitate the growth of the Lactobacillus strains brown sugar was added to the herbal substances used. For both DPPH radical scavenging activities and SOD-like activities the medicinal mixture, when fermented through heterogeneous co-cultures, scored higher (at 77% and 42%, respectively) than when not fermented (at 31.7% and 36.3%, respectively). The co-cultured Korean medicine inhibited the growth of Bacillus subtilis PCI 219, Pseudomonas aeruginosa KCTC 2004, Staphylococcus aureus subsp. aureus KCTC 1916 and Propionibacterium acnes KCTC 3314. The inhibiting effects on ${\beta}$-hexosaminidase released from RBL-2H3 cells caused by the mixture, with and without fermentation, was seen to be similar (57% and 60%, respectively).