• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.372-379
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• 2016

This study was performed to investigate the quality characteristics of various salted (8, 10, and 12%) Doenjang prepared with fermented Hwangchil (Dendropanax morbifera) extract as well as the effect of Bacillus methylotrophicus S8 strain, isolated from soy sauce, as a starter culture. After fermentation, the total cell number of low-salted Doenjang (8% and 10%) prepared with fermented Hwangchil was lower than that of Doenjang without fermented Hwangchil. Low-salted Doenjang (8% and 10%) showed higher total acidity, amino acid, and organic acid levels as well lower pH levels than high-salted Doenjang (12%), indicating active fermentation. The highest levels of lactic acid (48.1 mg/L) and glutamic acid (549.0 mg/L) were observed in low-salted Doenjang (8%) fermented with B. methylotrophicus S8 strain. The low-salted Doenjang (8%) fermented with B. methylotrophicus S8 also showed the highest score in overall preference of sensory evaluation. These results indicate that Hwangchil extract fermented with B. methylotrophicus S8 can be used as a starter for making low-salted Doenjang, resulting in improved palatability, and inhibition of abnormal fermentation.

• Journal of Life Science
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• v.13 no.1
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• pp.59-66
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• 2003

The bacterial strain was isolated from the 4th day's fermented Dolsan Leaf Mustard Kimchi(DLMK) at $20^{\circ}C$/TEX>. It was used as Kimchi starter, and then its physiological activity was investigated for 50 days at $4^{\circ}C$/TEX> and $10^{\circ}C$/TEX> The physiological activity of DLMK was examined for both antioxidative and Angiotensine Converting Enzyme(ACE) inhibitory activity. In the starter-inoculated DLMK(1 X $10^{10}$ CFU/mL) at 4 and $10^{\circ}C$, the optimal ripening period was more shortend than that of control(without starter) up to about 5.6 and 5 times, respectively. The maximal antioxidative activity in the starter-inoculated DLMK(1 X $10^{10}$ 10 CFU/mL) at 4 and $10^{\circ}C$ were 67% and 75%, respectively. The yield of cell concentration per day($lnX_{max}$/$t_{max}$) and the yield of antioxidative activity per day($P_{max}$/ｔ$t_{max}$) had a linear relationship. Also, the yield of antioxidative activity per day was increased with increasing the concentration of inoculated bacterium. By adding 1 X $10^{10}$ CFU/mL at 4 and $10^{\circ}C$, the ACE inhibitory activity of DLMK was maximal. The rates of inhibiting activities were 52% and 76%, respectively. Consequently, physiological activities were significantly affected by the inoculation concentrations of starter, but bacterium itself was not appeared the physiological activity. We assume that the bacterium metabolizes certain materials in DLMK and released compounds such as glucosinolates or its metabolized forms from DLMK show the antioxidative and ACE inhibitory activity.

• Journal of Dairy Science and Biotechnology
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• v.36 no.3
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• pp.178-185
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• 2018

Kefir, which originates in the Caucasian mountains, is a cultured milk beverage produced by a combination of acidic and alcoholic fermentation. Kefir products are commonly used as food vehicles to deliver health-promoting materials including kefran and lactic acid bacteria to consumers. The aim of this study was to develop a freeze-dried starter culture without yeast and assess the suitability of kefir-like dairy products for the growth of lactic acid bacteria and the acidification of milk. Pasteurized whole milk (SNF 8.5%) stored at $25^{\circ}C$ was aseptically inoculated with starter cultures (0.002% w/v); it was kept at $25^{\circ}C$ until the pH attained a value of 4.6. Ten grams of the kefir-like product sample was diluted with 90 mL of 0.15% peptone water diluent in a milk dilution bottle, followed by uniform mixing for 1 min. Viable cells of Lactobacillus species were enumerated on modified-MRS agar (pH 5.2), with incubation at $37^{\circ}C$ for 48 h. Viable cells of Lactococcus species were enumerated on M17-lactose agar, with incubation at $32^{\circ}C$ for 48 h. The pH attained a value of 4.6 after fermentation for 9 h 30 min (Starter 1), 9 h 45 min (Starter 2), and 12 h (Starter 3). The viable cell count of Lactobacillus sp. and Lactococcus sp. was initially $10^5{\sim}10^6CFU/g$; it increased significantly to $10^9CFU/g$ after 12 h of incubation. During the storage of the kefir-like products at $4^{\circ}C$ for 1 4 days, the total viable cell numbers were unchanged, but the pH decreased slightly. The consistency of the kefir products increased gradually during the storage. The organoleptic properties of the kefir products fermented using the new starter culture are more desirable than those of commercial kefir. These results suggest that the newly developed starter culture without yeast could be suitable for kefir fermentation.

• Korean Journal of Veterinary Service
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• v.29 no.3
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• pp.277-285
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• 2006

Plasmids are covalently closed circular molecules of DNA that are stably inherited and replicate somewhat independently of the bacterial chromosome. Genes carried on plasmids can mediate a wide variety of important functions, including antibiotics (R plasmids) and heavy metals resistance, toxins production, cell penetration, iron chelation, complement resistance, and metabolic characteristics such as sucrose and lactose fermentation. Fifty strains of lactobacilli were isolated from 26 staters and 29 fermented milk products. They were classified 27 strains as Lactobacillus paracasei subsp paracasei, 11 stains as Lactococcus lactis subsp cremoris, 6 strains as L delbrueckii subsp lactis, 4 strains as L acidophius, and 2 strains as L delbrueckii subsp bulgaricus. All of these strains were examined for drug resistance and transferability of R plasmids. All of the isolates were sensitive to Am, C, CF, E, NB, P, T, and Te. But resistant to SXT 94% (47 strains), K 66% (33 strains), S 56% (28 strains), ENR 50% (25 strains), NOR 38% (19 strains) CIP 38% (19 strains), GM 16% (8 strains), and N 14% (7 strains), in order. And 32 different resistant patterns were found. The most frequently encountered patterns were CIP-ENR-K-NOR-S-SXT (5 strains). In vitro R plasmids transfer experiment, 57 antibiotic resistant strains which were not transfer to the recipient 2 Escherichia coli strains by conjugation, These results indicate that Lactobacillus in internal trade market' stater recognize R factor but transmissible R plasmid is not existed.

• Preventive Nutrition and Food Science
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• v.20 no.4
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• pp.298-302
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• 2015

The anti-obesity effects of starter (Leuconostoc mesenteroides+Lactobacillus plantarum) fermented kimchi on 3T3-L1 adipocyte were studied using naturally fermented kimchi (NK), a functional kimchi (FK, NK supplemented with green tea), and FK supplemented with added starters (FKS). Oil red O staining and cellular levels of triglyceride (TG) and glycerol were used to evaluate the in vitro anti-obesity effects of these kimchis in 3T3-L1 cells. The expressions of adipogenesis/lipogenesis-related genes of peroxisome proliferator-active receptor (PPAR)-${\gamma}$, CCAAT/enhance-binding protein (C/EBP)-${\alpha}$, and fatty acid synthase (FAS) were determined by RT-PCR. Kimchis, especially FKS, markedly decreased TG levels and increased levels of intracellular glycerol and lipid lipolysis. In addition, FKS also reduced the mRNA levels of PPAR-${\gamma}$, C/EBP-${\alpha}$, and FAS, which are related to adipogenesis/lipogenesis in 3T3-L1 cells. These results suggest the anti-obesity effects of FKS were to due to enhanced lipolysis and reduced adipogenesis/lipogenesis in 3T3-L1 adipocytes.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.883-895
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• 2014

This study investigated quality characteristics of pan breads prepared with 0, 10, 20, 30 and 40% purple rice flour and naturally fermented blueberry-rice starters. RVA (Rapid Visco Analyzer) analysis showed that wheat flour retrogradation was not retarded by addition of purple rice flour. Using amylography, gelatinization tem. perature of purple rice flour samples was higher than that of the control, whereas maximum viscosity temperature. and maximum viscosity of purple rice flour samples were lower than those of the control. Weights of pan breads containing purple rice flour were lower than that of the control, whereas volume, specific volume and baking loss rate were higher than those of the control. The anthocyanin contents and antioxidative activites as measured by DPPH radical scavenging activity of breads increased as the concentration of purple rice flour increased. The moisture content of pan breads containing purple rice flour decreased as storage time increased. The pH of breads containing purple rice flour was higher than that of the control. Color L value decreased, whereas a and b values increased significantly, as storage time increased. In texture analyzer measurement, hardness of breads containing purple rice flour significantly increased as storage time increased. Breads containing 10~20% purple rice flour showed acceptable sensory properties, such as mouth feel, appearance, flavor, texture, taste and overall acceptability.

• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.251-261
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• 2017

Initially, we screened 18 Aspergillus sojae-like strains from Aspergillus spp. isolated from meju (Korean traditional fermented soybean brick) according to their morphological characteristics. Because members of Aspergillus section Flavi are often incorrectly identified because of their phylogenetic similarity, we re-identified these strains at the morphological and molecular genetic levels. Fourteen strains were finally identified as A. sojae. The isolates produced protease and ${\alpha}-amylase$ with ranges of 2.66-10.64 and 21.53-106.73 unit/g-initial dry substrate (U/g-IDS), respectively, which were equivalent to those of the koji (starter mold) strains employed to produce Japanese soy sauce. Among the isolates and Japanese koji strains, strains SMF 127 and SMF 131 had the highest leucine aminopeptidase (LAP) activities at 6.00 and 6.06 U/g-IDS, respectively. LAP plays an important role in flavor development because of the production of low-molecular-weight peptides that affect the taste and decrease bitterness. SMF 127 and SMF 131 appeared to be non-aflatoxigenic because of a termination point mutation in aflR and the lack of the polyketide synthase gene found in other A. sojae strains. In addition, SMF 127 and SMF 131 were not cyclopiazonic acid (CPA) producers because of the deletion of maoA, dmaT, and pks/nrps, which are involved in CPA biosynthesis. Therefore, A. sojae strains such as SMF 127 and SMF 131, which have high protease and LAP activities and are free of safety issues, can be considered good starters for soybean fermentations, such as in the production of the Korean fermented soybean products meju, doenjang, and ganjang.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.313-319
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• 2018

Halophilic lactic acid bacteria (LAB) were isolated from myeolchi-jeotgal (23% NaCl, w/v) fermented in jangdok (Korean earthenware) located outside a house. They were identified as Tetragenococcus halophilus by 16S rRNA and recA gene sequencing. Four T. halophilus isolates showing high protease activities were selected for further studies. Four strains grew well, reaching $OD_{600}$ values of 0.75-0.92 at 18% NaCl content (w/v) and 0.28-0.44 at 23% salt. They showed rapid growth, attaining $OD_{600}$ values of 1.1-1.2 at $20-30^{\circ}C$, but did not grow at $4^{\circ}C$. At $15^{\circ}C$, the highest $OD_{600}$ values, which exceeded 0.6, were observed at 20 days, and were higher than those of cultures at $37^{\circ}C$ and $42^{\circ}C$ (approximately 0.5). Four isolates grew best in broth where the initial pH was adjusted to 8 and did not grow at $pH{\leq}4$. T. halophilus BS2-36 showed the highest survival ratio of 18.7% after 2 hours of exposure at pH 3. BS2-36 showed the highest survival ratio (1.29%) in presence of 0.3% bile salts. T. halophilus BS2-36 seems a promising candidate as a starter for jeotgal and other fermented foods with high salinities.

• Korean Journal of Agricultural Science
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• v.48 no.4
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• pp.807-814
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• 2021

This study sought to evaluate the effects of fermented soybean meal (FSBM) prepared by inoculating Bacillus coagulans NRR1207 and a Kefir starter on sows and Holstein cow's. FSBM has high nutritional value due to the hydrolysis of anti-nutritional factors such as trypsin inhibitors, hemagglutinin, raffinose and stachyose. In particular, it is widely used as a type of livestock feed due to its high protein content. The composition of FSBM is as follows: crude protein 55.15%, crude fat 2.12% and 0.2% KOH solubility 83.17%, it was higher than soybean meal (SBM). In particular, anti-nutritional factors such as trypsin inhibitor, raffinose and stachyose of FSBM were significantly reduced compared to the SBM. The number of lactic acid bacteria, including B. coagulans NRR1207, is 8.63 × 10⁷ CFU·g^-1, yeast is 1.1 × 10⁶ CFU·g^-1. Offspring numbers, the initial sucking number, sucking days, and weaned numbers of sows fed with FSBM all showed higher values compared to the control group. The average body weight and backfat thickness of sows fed with FSBM increased than those fed with SBM. The weight body of piglets fed with FSBM increased by 1.4 kg compared to the control group. The feed conversion ratio of piglets fed with FSBM was reduced by 10.69% compared to the control group. The results of this study indicate that FSBM can provide beneficial effects with regard to the feeding characteristics of sows and piglets.

• Food Science of Animal Resources
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• v.42 no.1
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• pp.46-60
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• 2022

In this study, angiotensin-I-converting enzyme inhibitory (ACEI) activity was evaluated in fermented goat milk fermented by lactic acid bacteria (LAB) from fermented foods and breast milk. Furthermore, the potential for ACEI peptides was identified in fermented goat milk with the highest ACEI activity. The proteolytic specificity of LAB was also evaluated. The 2% isolate was inoculated into reconstituted goat milk (11%, w/v), then incubated at 37℃ until pH 4.6 was reached. The supernatant produced by centrifugation was analyzed for ACEI activity and total peptide. Viable cell counts of LAB and titratable acidity were also evaluated after fermentation. Peptide identification was carried out using nano liquid chromatography mass spectrometry (LC-MS/MS), and potential as an ACEI peptide was carried out based on a literature review. The result revealed that ACEI activity was produced in all samples (20.44%-60.33%). Fermented goat milk of Lc. lactis ssp. lactis BD17 produced the highest ACEI activity (60.33%; IC₅₀ 0.297±0.10 mg/mL) after 48 h incubation, viable cell counts >8 Log CFU/mL, and peptide content of 4.037±0.27/mL. A total of 261 peptides were released, predominantly derived from casein (93%). The proteolytic specificity of Lc. lactis ssp. lactis BD17 through cleavage on the amino acid tyrosine, leucine, glutamic acid, and proline. A total of 21 peptides were identified as ACEI peptides. This study showed that one of the isolates from fermented food, namely Lc. lactis ssp. lactis BD17, has the potential as a starter culture for the production of fermented goat milk which has functional properties as a source of antihypertensive peptides.