• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.328-333
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• 2014

Folate is a water-soluble vitamin B that is required for the synthesis of amino acids and nucleic acids. It plays an important role in cell division and cell growth in several living organisms. The purpose of this study was to screen strong folate-synthesizing bacteria and to optimize their culture conditions for folate production. Folate production was quantified by microbiological assays by using folate-dependent strain Lactobacillus rhamnosus KCTC 3237. Folate derivatives were identified by LC-MS/MS. Of the 65 strains of bifidobacteria and lactobacilli tested, L. plantarum Fol 708 demonstrated the greatest ability to produce folate. Its optimal pH for folate production was 5.5 in a pH-controlled, lab-scale fermenter. Coculturing L. plantarum Fol 708 with L. brevis GABA 100 in a milk medium enhanced the level of folate produced in comparison to culturing L. plantarum Fol 708 alone.

• Food Science and Preservation
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• v.16 no.3
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• pp.405-411
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• 2009

The manufacturing process and quality properties of Lactococcus lactis-fermented yakchobugak (LFY) containing some colored agro-food products were investigated to develop a good organoleptic bugak from the leaf of the medicinal herb. The de-oiling rate of LFY by centrifugation was 37.6%, which was significantly different to the 3.5% value obtained after standing and the 8.9% value obtained with the beating method (p<0.05). Reducing power (RS) increased with addition of increasing levels of ethanol extracts from agro-food powders. The RS of green tea extract-supplemented LFY had the highest value of 0.97 at $500{\mu}g/mL$, and this was significantly different to values obtained using other extracts (p<0.05). At 83.84%, the DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical scavenging activity of green tea extract-supplemented LFY was the greatest of all samples tested, followed by LFY with woolgeom at 39.48%, LFY with black rice at 28.45%, and LFY with bokbunja at 22.24% all ethanol extracts were added at $50{\mu}g/mL$ (p<0.05). Acid values of green tea and bokbunja LFYs stored in transparent PE bags at $60^{\circ}C$ for 7 days were 1.82% and 2.03%, respectively. Textural hardness values of LFYs were less than 250.62, except for LFYs with black rice and woolgeom, but these values increased $2{\sim}3$-fold after lactic acid fermentation. Carbohydrate and protein content of LFYs were in the ranges $58.95{\sim}64.63%$ and $7.50{\sim}8.68%$, respectively. Lipid and calorie contents of woolgeom LFY had the lowest values of 22.02% and 490 Kcal, respectively.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.583-589
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• 2013

We investigated the delay of kimchi fermentation by the addition of plant extracts. Fifteen plant extracts were screened for inhibitory activity aginst Lactobacillus plantarum by using an agar well diffusion assay, and determined the minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were determined. The lowest MIC for grapefruit seed extract (GFSE; 0.0313 mg/mL) was determined, followed by Caesalpinia sappan L. extract (CSLE; 0.25 mg/mL), and oregano essential oil (OREO; 1.0 mg/mL). GFSE, CSLE, and OREO were individually added to kimchi, and incubated the samples at 10 for up to 20 days. Results showed that the addition of GFSE (0.3 and 0.5%), CSLE (0.1, 0.3, and 0.5%), or OREO (0.5 and 1.0%) led to a significant increase in the pH of kimchi, and also a significant reduction in the numbers of lactic acid bacteria. Taken together, the addition of natural antimicrobial agents can delay kimchi fermentation.

• Food Science and Preservation
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• v.17 no.1
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• pp.50-57
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• 2010

To develop a new functional kimchi with antioxidative properties, salted baechu was soaked in black rice water extract for 6 h at room temperature. The antioxidative property of the water extract was $78.75{\pm}1.18%$ that of the control (0.1% [w/v] alpha-tocopherol). The black rice gel was added to the baechu kimchi preparation. The color of baechu kimchi treated with black rice water extract changed to dark violet and/or black. Control kimchi and black rice water-treated kimchi were stored at $4^{\circ}C$ for 30 days. No significant differences were detected between the control and the black rice water-treated group in the early stages of fermentation. As fermentation time increased, pH decreased and titratable acidity increased rapidly in control kimchi. However, such marked changes were not evident in test kimchi. The hardness value of black rice water-treated kimchi was higher than that of control kimchi after the midpoint of the fermentation period. The storage life of baechu kimchi treated with black rice water extract was prolonged by up to 5 days compared with control samples, owing to a decline in lactic acid bacteria and yeast levels during the final fermentation period in black rice water-treated kimchi. The total phenolic levels and the antioxidative capacity of black rice water-treated kimchi (83%) were approximately 1.5-fold higher than in control kimchi (57%). In sensory evaluation, black rice water-treated kimchi scored higher than did control kimchi using a blind test protocol.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.267-274
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• 2014

High pressure processing (HPP) is a non-thermal method used to prevent bacterial growth in the food industry. Currently, pasteurization is the most common method in use for most milk processing, but this has the disadvantage that it leads to changes in the milk's nutritional and chemical properties. Therefore, the effects of HPP treatment on the microbiological and chemical properties of milk were investigated in this study. With the treatment of HPP at 600 MPa and $15^{\circ}C$ for 3 min, the quantity of microorganisms and lactic acid bacteria were reduced to the level of 2-3 log CFU/ml, and coliforms were not detected during a storage period of 15 d at $4^{\circ}C$. An analysis of milk proteins, such as ${\alpha}$-casein, ${\beta}$-casein, ${\kappa}$-casein, ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin by on-chip electorophoresis revealed that the electrophoretic pattern of the proteins from HPP-treated milk was different from that of conventionally treated commercial milk. While the quantities of vitamins and minerals in HPP-treated milk were seen to be comparable to amounts found in raw milk, the enzyme activity of lipase, protease and alkaline phosphatase after HPP treatment was reduced. These results suggest that HPP treatment is a viable method for the control of undesirable microorganisms in milk, allowing for minimal nutritional and chemical changes in the milk during the process.

• Food Science and Preservation
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• v.19 no.6
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• pp.951-956
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• 2012

In this study, the effects of the use of a starter on radish soaked at $4^{\circ}C$ for 28 days using two kinds of domestic sun-dried salt (white and gray salt) were determined. As a result, the moisture contents of the radish soaked with white and gray salt were 7.93 and 4.50%, respectively. The salinity levels were found to be equal (90%). No significant difference was found between the two groups in terms of the mineral contents of the salts therein ($37812.41{\pm}1922.95$ and $39755.13{\pm}1205.70$ mg/100 g, respectively). However, iron and zinc contents of gray salt were higher than those of white salt while the calcium, potassium, and magnesium contents were lower than those of white salt. After the addition of the starter, the sugar content increased, the pH decreased, and the total acidity rapidly decreased compared with the non-starter group during fermentation. The total microorganism count of the two groups increased during the fermentation period of 28 days. From the initial fermentation for 7 days, the lactic acid bacteria in the non-starter group increased while those in the leuconostoc starter group steadily increased within the whole fermentation period. The Leuconostoc spp. in non-starter group increased, but that in the starter group decreased to pH 4.0 on day 14.

• Journal of Life Science
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• v.29 no.5
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• pp.545-554
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• 2019

The phytochemical compounds of Pueraria, a medicinally important leguminous plant, include various isoflavones that have weak estrogenic activity and a potential role in preventing chronic disease, cancer, osteoporosis, and postmenopausal syndrome. However, the major isoflavones are derivatives of puerarin and occur mainly as unabsorbable and biologically inactive glycosides. The bioavailability of the glucosides can be increased by hydrolysis of the sugar moiety using ${\beta}$-glucosidase. In this study, we investigated the antioxidant effects of a Pueraria extract after fermentation by Lactobacillus rhamnosus BHN-LAB 76. The L. rhamnosus BHN-LAB 76 strain was inoculated into Pueraria powder and fermented at $37^{\circ}C$ for 72 hr. The total polyphenol content of the Pueraria extract increased by about 134% and the total flavonoid content increased around 110% after fermentation with L. rhamnosus BHN-LAB 76 when compared to a non-fermented Pueraria extract. Superoxide dismutase-like activities, DPPH radical scavenging, and ABTS radical scavenging increased by approximately 213%, 190%, and 107%, respectively, in the fermented Pueraria extract compared to the non-fermented Pueraria extract. Fermentation of Pueraria extracts with L. rhamnosus BHN-LAB 76 is therefore possible and can effectively increase the antioxidant effects. These results can be applied to the development of improved foods and cosmetic materials.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.2
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• pp.187-198
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• 1997

This experiment was conducted to evaluate effects of wilting and additives on fermetation characteristics, quality and aerobic stability of silage of rye(Seca1e cereale L.) harvested at the early heading stage. Harvested rye was wilted or mixed with beet pulp and then treated with formic acid or lactic acid bacteria(LAB) inoculant. Treatments were consisted of direct cut(DC), wilted(WT), beet pulp added(BP), direct cut and formate applied(DF), wilted and formate applied(WF), beet pulp and formate applied(BF), direct cut and LAB inoculated(DL), beet pulp added and LAB inoculated(BL), and wilted and LAB inoculated(WL) silages. Afler 70 days of ensiling period, the silages were opened and exposed to air for 7 days, and the silages of opening day(0 day) were compared with the silages exposed to air for 7 days(7 day). 1. LAB inoculated rye silages(DL, WL, BL) lowered pH values effectively eom the third day of ensiling and showed most stable pattern of pH changes during the initial fermentation process. Direct cut and formate applied(DF), beet pulp and formate applied(BF) and beet pulp added(BP) silages were also effective in lowering pH from the seventh day thai direct cut treatment(DC). 2. pH was low below 3.7 in all treatments of 0 day. After 7-day period of aerobic exposure, DL and WL showed considerable increases in pH from 3.5 and 3.4 to 8.3 and 6.4, respectively. 3. Direct cut rye silages(DF, DC, DL) and beet pulp and formate treatment(BF) produced effluent of 121.2, 85.9, 80.3 and 34.2 mlkg, respectively and these were greater than others(P<0.01). Beet pulp retained 1.61 I/kg of effluent at the application rate of 50 kg/t in comparing BP with DC, and formate application increased the amount of effluent in comparing DF and BF with DC and BP, respectively(P<0.01). 4. Beet pulp and LAB treatment(B1) was highest in content of lactate as 3.1% and formate treated silages(DF, WF, BF) showed lower content of lactate and total acid than others. LAB inoculated(D1, WL, BL) and wilted (WT) silages were graded to be good quality as a second group by the Flieg's score. Formate applied silages (DF, WF, BF) were graded as a foum group lower than DC by one. 5. Residual content of WSC of rye silage was higher in BP, BF, DL and BL than direct cut treatment(M3) (P< 0.01). Formate application had a tendency to increase the content of residual content of WSC. 6. For the ratio of NH3-N to Total N, wilted and LAB inoculated(W1) and direct cut and LAB inoculated(D1) silages were lowest on 0 day as 8.9 and 9.3% respectively. But after 7-day period of aerobic exposure, WL and DL showed largest increase of the ratio of $NH_3-N$ to Total N from 0 day(P<0.01). 7. On 0 day wilted(WT), beet pulp and formate treatment(BF), and beet pulp and LAB treatment(B1) were lower than direct cut treatment(DC) for NDF and ADF concentrations consistently. Formate applied silages (DF, WF, BF) made little change in ADF and NDF concentrations during 7 day period of aerobic exposure. DL and WL showed a large increase in ADF and NDF concentrations under aerobic condition(P<0.01). 8. IVDMD values of wilted(WT), beet pulp added(BP), wilted and LAB inoculated(W1) and beet pulp added and LAB inoculated(B1) silages were higher than direct-cut treatmentPC) as 84.7, 84.7, 84.4 and 83.0%, respectively on 0 day. But during 7-day period of aerobic exposure, a great decreae in IVDMD of WL was showed(P<0.01). The experimental results indicate that wilted silage(WT) could be recommended as the most effective treatment for reducing efluent and increasing quality and feed value of rye silage without deteriorating aerobic stability more than direct cut treatment(DC). Additionally, under unfavorable weather condition beet pulp added and LAB inoculated treatment(T3L) might be the possible alternative for successful ensiling of forage rye.

• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.17-23
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• 2018

The purpose of this study was to produce mulberry extract and silk protein (MS) added yogurt fermented with vegetable lactic acid bacteria (Lactobacillus plantarum and Bacillus acidiproducens) and to determine their physicochemical properties and preference. The physicochemical properties were examined total phenol and antocyanins contents, viscosity, visible cell counts, chromaticity and sensory evaluation. Yogurt made with LP (PL) and BA (BA) had similar pH and titrable acidity and mulberry and MS addition made lower pH and higher titrable acidity than the control (YF) (p <0.05). The MS added yogurt exhibited adaptable acidity in the market. As expected, MS added yogurt had higher redness, and lower lightness and yellowness than no added one regardless of bacteria kinds, in chromaticity (p <0.05). MS added yogurt showed higher value of total phenols and anthocyanins than no MS added one. MS added yogurt also increased the number of live bacteria in the ascending order of than LP, BA, YF, LP + MS, and BA + MS. In sensory evaluation, BA + MS had the higher overall acceptance than the others. In conclusion, yogurt fermented with Lactobacillus plantarum and Bacillus acidiproducens was acceptable as much as the commercial Lactobacillus. Moreover, MS added yogurt fermented with Bacillus acidiproducens was the most preferred, based on physicochemical properties and overall acceptability for sensory evaluation.

• Food Science and Preservation
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• v.23 no.3
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• pp.361-368
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• 2016

The objective of this study was to investigate the nutritional composition and antioxidant activity of a mixture of rice bran and bodies of Sparassis crispa fermented with lactic acid bacteria (LAB). LAB-fermented S. crispa mixture had higher water, crude lipid and crude ash content than that of S. crispa. Insoluble dietary fiber contents of the dried powder of S. crispa and LAB-fermented S. crispa mixture were 46.13% and 33.46%, respectively. ${\beta}$-glucan was higher in dried S. crispa (38.03%) than in LAB-fermented S. crispa mixture (5.44%). Dried S. crispa contained mainly fructose and glucose instead of containing sucrose in LAB-fermented S. crispa mixture. No significant differences in the total polyphenol contents were found in between dried S. crispa and LAB-fermented S. crispa mixture. Total flavonoid content was significantly higher in LAB-fermented S. crispa mixture than in dried S. crispa. No significant differences were found in the DPPH radical scavenging activity and in the antioxidant index between dried S. crispa and LAB-fermented S. crispa mixture. Finally, ABTS radical scavenging activity of LAB-fermented S. crispa mixture was significantly higher than that of dried S. crispa. These results may provide the basic data for future studies for a better understanding of the biological activities of LAB-fermented S. crispa mixture.