• Korean Journal of Food Science and Technology
• /
• v.21 no.3
• /
• pp.331-337
• /
• 1989

In order to investigate the method for extension of shelf-life of Kimchi, the effect of low temperature heating and addition of mustard oil on pH and total acidity of Kimchi during storage at $15^{\circ}C$ were studied. Mustard oil was found to have the antimicrobial effect on the major lactic acid bacteria of Kimchi such as Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides and Pediococcus cerevisiae, Addition of 200p.p.m. mustard oil, 0.1% mustard powder and 0.01% $H_2O_2$ to Kimchi effectively reduced the fermentation rate of Kimchi. Low temperature heating of salted cabbage and addition of 200p·p.m. mustard oil and 0.01% $H_2O_2$ to seasonings extented the time reaching optimum ripening of Kimchi about 2.5 times longer than control. Combination of low temperature heating, addition of mustard oil and $H_2O_2$ to seasonings and post low temperature heating delayed fermentation time Kimchi about 5 times longer than control after 15 days storage at $15^{\circ}C$.

• Korean Journal of Food Science and Technology
• /
• v.30 no.1
• /
• pp.168-174
• /
• 1998

The amount of D(-)-lactic acid in fermented dairy products is very important because the rate of metabolism of D(-)-lactic acid is lower than that of L(+)-lactic acid. The purpose of this study was to investigate the optimum condition during fermentation and storage of yogurt for the formation of isomers of lactic acid by Lactobacillus acidophilus NCFM. The production of acid was excellent at $37^{\circ}C$ of fermentation and the ratio of D(-)-lactic acid was also lower than that of other conditions such as $35^{\circ}C{\;}and{\;}40^{\circ}C$. Among shaking and non-shaking treatment under aerobic condition and anaerobic condition, non-shaking treatment under aerobic condition was the best condition at the production of acid and L(+)-lactic acid during fermentation. During storage at low temperature, a larger amount of L(+)-lactic acid was produced than at higer storage temperature.

• Korean Journal of Food Science and Technology
• /
• v.29 no.6
• /
• pp.1275-1280
• /
• 1997

The possible use of tea catechins as natural preservatives for kimchi was investigated in this study. Tea catechins separated from tea leaves had antimicrobial activity against microorganisms related to kimchi fermentation, such as Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus brevis, Pediococcus cerevisiae, Streptococcus faecalis. The degree of antimicrobial activity of catechins were different among microorganisms; that is 2 mg/mL to Leuconostoc mesenteroides, Lactobacillus plantarum, and Pediococcus cerevisiae, 4 mg/mL to Streptococcus faecalis, and 5 mg/mL to Lactobacillus brevis; however, Saccharomyces cerevisiae can not be inhibited. The effect of tea catechins on retardation of kimchi fermentation was tested by measuring changes in pH and acidity. The changes of pH and acidity of baechu-kimchi and mul-kimchi were remarkably inhibited by adding the tea catechins at the level of 2 mg/g fresh baechu. These results suggest that the tea catechins can be successfully used for the extension of shelf-life of kimchi.

• Journal of Applied Biological Chemistry
• /
• v.62 no.3
• /
• pp.257-264
• /
• 2019

Rice bran is considered a natural source of antioxidants. In this study, rice bran was fermented with lactic acid bacteria to increase its antioxidant activity. Four strains isolated from fermented food, Lactobacillus plantarum MJM60383, Lactococcus lactis subsp. lactis MJM60392, Lactobacillus fermentum MJM60393, and Lactobacillus paracasei MJM60396, were confirmed as safe through stability tests such as safety assessment for biogenic amine production, hemolytic activity, and mucin degradation, and showed high reducing capacity. The antioxidant activity of rice bran fermentation altered by these strains was evaluated using several methods including measurement of $Fe^{2+}$ chelating activity and scavenging activity by 1,1-diphenyl-2-picryl-hydrazil (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and nitric oxide assays. In this study, the total phenolic content and ${\gamma}$-oryzanol were evaluated by high-performance liquid chromatography. Compared to non-fermented rice bran and a commercial product, rice bran fermented with Lactococcus lactis subsp. lactis MJM60392 showed the highest phenolic content (844.13 mg GAE/g). Moreover, the content of ferulic acids, ${\rho}$-coumaric acid, and ${\gamma}$-oryzanol in rice bran increased after fermentation with L. lactis subsp. lactis MJM60392 and L. fermentum MJM60393 compared to other samples. Indeed, the DPPH radical scavenging activity and NO scavenging activity were also found to be high in these fermented rice brans. These results indicated that fermentation with lactic acid bacteria increases the active compound levels and the potent antioxidant activities of rice bran.

• Korean Journal of Food Science and Technology
• /
• v.45 no.5
• /
• pp.571-577
• /
• 2013

Our aim was to ferment soymilk using lactic acid bacteria that showed protease activity and to optimize the condition for fermentation. In total, 108 strains of protease-producing lactic acid bacteria were isolated from various fermented foods such as kimchi and jeotgal, and among them, 29 strains displaying the highest protease activity were selected for further study. From these 29 strains, strain MK1, whose protease activity was 126 $mU/mL{\cdot}min$, was selected as the optimal fermentation strain owing to its high ability to digest soymilk protein. It was henceforth labeled as Lactobacillus paracasei MK1. The optimum conditions for the fermentation of soymilk by using L. paracasei MK1 were determined to be as follows: 30 h of fermentation time at a temperature of $30^{\circ}C$, and at a pH of 6.0 in the initial growth medium.

• Journal of Life Science
• /
• v.26 no.4
• /
• pp.468-474
• /
• 2016

This study was performed to evaluate the possibility of application of lactic acid bacteria fermentation to increase the anti-oxidative activity of extracts from Houttuynia cordata Thunb. Houttuynia cordata Thunb. was fermented by two species of lactic acid bacteria, Leuconostoc mesenteroides 4395 and Lactobacillus sakei 383. The anti-oxidative activities of Houttuynia cordata Thunb. extracts were analyzed both before and after fermentation. Anti-oxidative activity was determined by in vitro assays to measure 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging and super oxide dismutase (SOD)-like activities, and by determining total flavonoid and total phenolic compound contents. The extracts of fermented Houttuynia cordata Thunb. had higher anti-oxidative activity than the unfermented control. The DPPH scavenging activity of the extracts after fermentation by Leuconostoc mesenteroides 4395 at 30℃ for 5 days was 71.67±0.52%, and after Lactobacillus sakei 383 fermentation at 35℃ for 5 days was 70.11±0.67%; these activities were both about 20% higher than the control. Increases of about 10 mg GAE/g of total phenolic compounds were found in both fermented extracts and both contained about 6 mg quercetin equivalents/g of total flavonoids, compared with 35.90±0.61 mg/g and 21.69±1.52 mg/g in the control, respectively. These results also suggested that fermentation time and temperature were important factors in determining the anti-oxidative effect of extracts from fermented Houttuynia cordata Thunb. These findings should be valuable for the development of medicines or functional foods with antioxidative activity.

• Journal of Mushroom
• /
• v.13 no.1
• /
• pp.50-55
• /
• 2015

Glucan has been shown to have a significant role in the activation of the immune system, including increased activity of macrophages and so on. Sparassis latifolia (formerly S. crispa) is an edible mushroom abundant in dietary fiber and widely known to contain high levels of ${\beta}$-glucan. In the present study, fermentation broths containing soluble ${\beta}$-glucan were prepared by fermentation with mushrooms with four Lactobacillus species (L. plantarum subsp. Plantarum, L. acidophilus, L. helveticus, and L. delbrueckii subsp. Bulgaricus). After culturing four Lactobacillus spp. in MRS broth, each Lactobacillus was inoculated into MRS broth containing S. latifolia powder 5% (w/v) at $37^{\circ}C$ in an anaerobic incubator for five days. It showed that the ${\beta}$-glucan contents were different in each fermentation sample. The suitable conditions for the preparation of mushroom fermentation broths were investigated and discussed.

• Korean Journal of Microbiology
• /
• v.39 no.1
• /
• pp.45-50
• /
• 2003

The diversity and change of microbial communities during kimchi fermentation at $4^{\circ}C$ were analyzed by denaturing gradient gel electrophoresis (DGGE). Kimchi samples were taken every 5 days over the fermentation periods (for 60 days) to extract total DNA for DGGE analysis. Touchdown polymerase chain reaction was performed to amplify the V3 region of 16S rRNA gene. Sequencing results of partial 16S rDNA amplicons from DGGE profiles revealed that lactic acid bacteria (LAB), especially Weissella koreensis, Lactobacillus sakei and Leuconostoc gelidum were dominants in kimchi fermentation at $4^{\circ}C$. And we knew that W. koreensis steadily existed throughout the whole fermentation period, also Lb. sakei and Leuc. gelidum appeared from 10th day and 30th day of fermentation time, respectively and then these species were to be dominant microorganisms.

• Korean Journal of Organic Agriculture
• /
• v.21 no.3
• /
• pp.467-476
• /
• 2013

This study was conducted to investigate the effect of fermentation on biological activity of Chelidonium majus var asiaticum and to screen effective starter culture strains. Antibacterial activity against to Staphylococcus aureus, Listeria monocytogenes and Salmonella gallinarum and antioxidant activity as free radical scavenging activity by using DPPH were tested. Total six starter culture strains, two of Lactobacillus brevis, one of Lactobacillus plantarum and three of Saccharomyces cerevisiae were used. Plant extract was prepared after fermentation by using ethanol. All strains showed normal growth in viable cell counts of fermented cultures and L. plantarum showed the highest cell growth significantly (p<0.05). In antibacterial activities of extracts, the activity was found only in the extract from the fermentation using L. plantarum. In antioxidant activity, the highest activity was shown in the fermentation using L. plantarum significantly (P<0.05). Newly produced spots in two of three elution systems on TLC-DPPH test were detected in the fermentation using L. plantarum.

• Korean Journal of Medicinal Crop Science
• /
• v.20 no.6
• /
• pp.472-478
• /
• 2012

This study was carried out to investigate solid-state fermentation method using cellulolytic lactic acid bacteria Lactobacillus plantarum TO-2100 in order to increase piperidine alkaloid contents in mulberry leaves. Piperidine alkaloid, one type of which include 1-deoxynojirimycin (1-DNJ), is known to inhibit ${\alpha}$-glycosidase activities. Using this strain, the optimal solid-state fermentation conditions on mulberry leaves powder were found as the following: initial moisture content, temperature and relative humidity were 20%, $30{\sim}35^{\circ}C$ and 60 ~ 70%, respectively, and the fermentation time was 72 hrs. The piperidine alkaloid contents in the fermented mulberry leaves were 2.86% on dry powder, which is 7-fold increase from that of non-fermented mulberry leaves. The 1-deoxynojirimycin contents after applying preparative thin layer chromatography were 2.02% on dry powder, which is 8 times higher than that of non-fermented mulberry leaves. ${\alpha}$-Glycosidase activities was inhibited by 65.7 ~ 84.7% with 3 ~ 5% treatments of hot-water extracts of the fermented mulberry leaves, compared to 16.2 ~ 40.2% with 3 ~ 5% treatments of hot-water extracts of non-fermented mulberry leaves. Therefore, the results suggest that solid-state fermentation method does indeed increase of piperidine alkaloid contents on mulberry leaves.