• Food Science and Preservation
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• v.22 no.6
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• pp.851-858
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• 2015

This study was designed to improve the sensory characteristics and mitigate the bitter taste of Platycodon gradiflorum. It was aimed at investigating the qualitative properties of fermented P. gradiflorum after repeated steaming and drying treatments. P. gradiflorum was heated for 2 hr at $95^{\circ}C$, being the first and third treatments compared afterwards. Lactobacillus plantarum, at a concentration of 10%, was used as starter culture. As a result, the third steaming process and the addition of starter improved the physical and chemical properties of P. gradiflorum i.e., crude saponin and total polyphenol contents increased significantly. Moreover, P. gradiflorum steamed three times and fermented by L. plantarum showed the higher overall preference score. Our results indicated that the three-time steaming and drying was an effective manufacturing process for the production of high-quality fermented P. gradiflorum. Lactic acid-fermented P. gradiflorum also could have a potential use as a valuable resource for the development of functional products.

• Food Science of Animal Resources
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• v.35 no.6
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• pp.738-747
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• 2015

Angiotensin-converting enzyme (ACE) inhibitory activity was evaluated for the low-molecular-weight fraction (<3 kDa) obtained from milk fermentation by Bifidobacterium longum KACC91563. The ACE inhibitory activity in this fraction was 62.3%. The peptides generated from the <3 kDa fraction were identified by liquid chromatography-electrospray ionization quantitative time-of-flight mass spectrometry analysis. Of the 28 peptides identified, 11 and 16 were identified as β-casein (CN) and α_s1-CN, respectively. One peptide was identified as κ-CN. Three peptides, YQEPVLGPVRGPFPIIV, QEPVLGPVRGPFPIIV, and GPVRGPFPIIV, from β-CN corresponded to known antihypertensive peptides. We also found 15 peptides that were identified as potential antihypertensive peptides because they included a known antihypertensive peptide fragment. These peptides were as follows: RELEELNVPGEIVE (f1-14), YQEPVLGPVRGPFP (f193-206), EPVLGPVRGPFPIIV (f195-206), PVLGPVRGPFPIIV (f196-206), VLGPVRGPFPIIV (f197-206), and LGPVRGPFPIIV (f198-206) for β-CN; and APSFSDIPNPIGSENSEKTTMPLW (f176-199), SFSDIPNPIGSENSEKT- TMPLW (f178-199), FSDIPNPIGSENSEKTTMPLW (f179-199), SDIPNPIGSENSEKTTMPLW (f180-199), DIPNPIGSENSEKTTMPLW (f181-199), IPNPIGSENSEKTTMPLW (f182-199), PIGSENSEKTTMPLW (f185-199), IGSENSEKTTMPLW (f186-199), and SENSEKTTMPLW (f188-199) for α_s1-CN. From these results, B. longum could be used as a starter culture in combination with other lactic acid bacteria in the dairy industry, and/or these peptides could be used in functional food manufacturing as additives for the development of a product with beneficial effects for human health.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1527-1532
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• 2016

Strain SPF4211, having hyaluronidase (HAase) inhibition activity, was isolated from P. davidiana (Carriere) Franch fruit (PrDF) sugar extract. The phenotypic and biochemical properties based on 16S rDNA sequencing and an API 50 CHB kit suggested that the organism was B. subtilis. To optimize the HAase inhibition activity of PrDF extract by fermentation of strain SPF4211, a central composite design (CCD) was introduced based on three variables: concentration of PrDF extract (X₁: 1-5%), amount of starter culture (X₂: 1-5%), and fermentation time (X₃: 0-7 days). The experimental data were fitted with quadratic regression equations, and the accuracy of the equations was analyzed by ANOVA. The statistical model predicted the highest HAase inhibition activity of 37.936% under the optimal conditions of X₁ = 1%, X₂ = 2.53%, and X₃ = 7 days. The optimized conditions were validated by observation of an actual HAase inhibition activity of 38.367% from extract of PrDF fermented by SPF4211. These results agree well with the predicted model value.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.2
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• pp.125-140
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• 2016

We analyzed the cultural characteristics of isolated brewing fungi for developing fermentation starters. In a previous study, we collected 87 domestic nuruk, from which 481 fungi strains were isolated and 11 were selected showing improved productivity. After culturing these 11 fungi strains in several types of media, temperatures, carbon and nitrogen sources, Rhizopus sp. grew well in MEA, ME20S, PDA medium while Aspergillus sp. grew well in ME20S and YES. Both Rhizopus sp. and Aspergillus sp. survived well at optimal growth temperatures of 30 and $37^{\circ}C$. Rhizopus sp. utilized lactose, glucose and peptone sources while Aspergillus sp. utilized glucose, mannose, fructose and yeast extract sources. ${\alpha}-Amylase$ activity was excellent in L. ramosa CN044, R. oryzae 82-7(MEB), R. oryzae CN174 and A. oryzae 58-11(WEB) culture extracts. This study suggests that R. delemar 26-4, 58-8 and A. oryzae 78-5, 37-7 might be appropriate fungi strains for fermentation starters based on development of large fungi bodies and their good enzyme activities.

• Food Science of Animal Resources
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• v.29 no.1
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• pp.15-23
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• 2009

In order to develop a new starter for fermented milk, 2082 bacteria were isolated from raw milk. The strain that showed excellent acid forming and ${\gamma}$-aminobutyric acid (GABA) production ($711.40{\mu}g/g$ D.W) characteristics after incubation at $37^{\circ}C$ for 18 hr was selected and identified as Lactobacillus acidophilus by the result of API carbohydrate fermentation pattern and 16S rDNA sequence. L. acidophilus RMK567 was investigated for its physiological characteristics. RMK67 strain showed good GABA production compared with commercial lactic acid bacteria. The optimum growth temperature of L. acidophilus RMK567 was $40^{\circ}C$ and cultures took 15 hr to reach pH 4.3. L. acidophilus RMK567 showed higher sensitivity to penicillin-G, novobiocin, as compared to other 14 different antibiotics. However, it showed more resistance to kanamycin, neomycin, streptomycin. It showed higher leucine arylamidase and ${\beta}$-galactosidase activities compared to 16 other enzymes. It was comparatively tolerant to bile juice and able to survive at pH 2 for 3 hr. It showed resistence to Escherichia coli, Salmonella typhimurium and Staphylococcus aureus with rates of 29.2%, 39.1% and 51.4%, respectively. Based on these and previous results, L. acidophilus RMK567 could be an excellent starter culture for fermented milk with excellent GABA contents.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.587-595
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• 2008

In order to develop a new starter for fermented milk, 1037 bacterial strains were isolated from raw milk. The strain that showed excellent acid producing and angiotensin converting enzyme (ACE) inhibitory activity (88.6%) was selected and identified as a Lactobacillus zeae based on the result of API carbohydrate fermentation pattern and 16S rDNA sequence. Lactobacillus zeae RMK354 was investigated further to study its physiological characteristics. It showed strong ACE inhibitory activity compared with commercial LAB starters tested. The optimum growth temperature of L. zeae RMK354 was $40^{\circ}C$ and it took 10 hr to reach pH 4.3 under this condition. L. zeae RMK354 showed more sensitive to penicillin-G, bacitracin, novobiocin, in a comparison of 14 different antibiotics, and showed most resistance to polymyxin B and vancomycin. It showed higher esterase and leucine arylamidase activities compared with 16 other enzymes. It was comparatively tolerant to bile juice and able to survive at pH 2 for 3 hr. It showed inhibitory activity against Salmonella Typhimurium with the rate of 60%. Based on these and previous results, L. zeae RMK354 could be an excellent starter culture for fermented milk with high level of ACE inhibitory activity.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.346-351
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• 2005

The physiochemical characteristics and sensory properties of Jinyang-ju was investigated on pH, total acidity, alcohol content, conductivity, dissolved solid, turbidity, reducing sugar content and sensory evaluation. Glutinous rice starter showed the enzyme activity that the ${\alpha}-amylase$ was 121.0 unit, ${\beta}-amylase$ was 40.0 unit and acidic. neutrality protease were 34.2, 23.7 unit, while the nonglutinous rice starter showed ${\alpha}-amylase$ was 156.0 unit, ${\beta}-amylase$ was 45.2 unit, acidic neutrality protease were 9.06, and 0.1 unit, respectively. The pH of the glutinous rice Jinyang-ju and nonglutinous rice Jinyang-ju showed the value of 5.33 and 4.04, total acidity of 2.30% and 2.05%, alcohol(%) of $2.58{\sim}13.5%\;and\;2.51{\sim}15.5%$, total organic acid content(mg%) of 4.35 and 7.63, free sugar of 4.98 mg% and 2.90 mg%, respectively. The sensory evaluation showed that the glutinous rice Jinyang-ju was more acceptable value than nonglutinous rice Jinyang-ju.

• Mycobiology
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• v.42 no.4
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• pp.368-375
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• 2014

Red ginseng (Panax ginseng), a Korean traditional medicinal plant, contains a variety of ginsenosides as major functional components. It is necessary to remove sugar moieties from the major ginsenosides, which have a lower absorption rate into the intestine, to obtain the aglycone form. To screen for microorganisms showing bioconversion activity for ginsenosides from red ginseng, 50 yeast strains were isolated from Korean traditional meju (a starter culture made with soybean and wheat flour for the fermentation of soybean paste). Twenty strains in which a black zone formed around the colony on esculin-yeast malt agar plates were screened first, and among them 5 strains having high ${\beta}$-glucosidase activity on p-nitrophenyl-${\beta}$-D-glucopyranoside as a substrate were then selected. Strain JNO301 was finally chosen as a bioconverting strain in this study on the basis of its high bioconversion activity for red ginseng extract as determined by thin-layer chromatography (TLC) analysis. The selected bioconversion strain was identified as Candida allociferrii JNO301 based on the nucleotide sequence analysis of the 18S rRNA gene. The optimum temperature and pH for the cell growth were $20{\sim}30^{\circ}C$ and pH 5~8, respectively. TLC analysis confirmed that C. allociferrii JNO301 converted ginsenoside Rb1 into Rd and then into F2, Rb2 into compound O, Rc into compound Mc1, and Rf into Rh1. Quantitative analysis using high-performance liquid chromatography showed that bioconversion of red ginseng extract resulted in an increase of 2.73, 3.32, 33.87, 16, and 5.48 fold in the concentration of Rd, F2, compound O, compound Mc1, and Rh1, respectively.

• Food Science and Preservation
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• v.22 no.6
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• pp.920-925
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• 2015

The microbial composition in Nuruk, a Korean cereal fermentation starter, is a critical factor for the quality and organoleptic properties of traditional alcoholic beverages. This study was aimed at monitoring the compositional change and enzyme activity of culturable lactic acid bacteria (LAB) in two types of Nuruk fermented at different temperatures. All culturable LAB were isolated at various time points (0, 3, 6, 10, 20, and 30 days) and identified by 16S rRNA sequencing. In traditional Nuruk type A (TN-A), which was fermented at $36^{\circ}C$, the population of total culturable LAB during the fermentation period was between $10^4$ and $10^5$ log CFU/mL. On the other hand, the LAB population in traditional Nuruk type B (TN-B) fermented at $45^{\circ}C$ (primary fermentation for 10 days) and $35^{\circ}C$ (secondary fermentation for 20 days) was $10^2$ log CFU/mL; however, these bacteria could not be detected after 6 days. Major LAB strains were identified in both Nuruk types: (1) from the MRS-culture of TN-A, Pediococcus pentosaceus at 3-30 days; (2) from MRS-culture of TN-B, P. pentosaceus at 3 days and Enterococcus hirae at 6 days. The protease activities of the dominant LAB isolated from the TN-A and TN-B cultures were within the ranges of 0.64~1.03 mg/mL and 0.74~0.81 mg/mL (tyrosine content), respectively, whereas the ${\alpha}$-amylase activities were 0.75~0.98 mg/mL and 0.78~0.79 mg/mL (amylose content), respectively.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.943-951
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• 2022

In this study, 8 kinds of fruits and vegetables such as apples, pears and radishes were cut and hot water extracts and Steamed hot water extract from fruits and vegetables were prepared and used as experimental substrates. As a result of fermenting with 1% (W/V) red ginseng extract (W/V) and 8 types of lactic acid bacteria mixed starter added to the lactic acid bacteria fermented extract, the pattern and content of ginsenosides were almost unchanged in the fruit and vegetable extract group and the steam treatment group. However, in the lactic acid bacteria fermented group, the TLC pattern was changed according to the fermentation process and treatment, and the content of ginsenosides converted into Rg₃(S) and Rg₅ increased. No change in the number of lactic acid bacteria (cfu) was observed in all four types of fruit and vegetable extracts. The number of lactic acid bacteria CFU was slightly decreased in the four fermented groups of fruit and vegetable extracts, but the growth inhibitory effect of beneficial bacteria was not significant. The growth inhibitory effect of the three harmful bacteria was not affected by the growth of E. coli and Pseudomonas in the four fruit and vegetable extracts. However, the proliferation of Salmonella was inhibited, which was confirmed as the growth inhibitory effect of the fruit and vegetable extract regardless of whether the steamed hot water extract or red ginseng extract was added.