• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.41-46
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• 2011

A galactose-fermenting yeasts, Saccharomyces cerevisiae No. 9, was selected by screening their abilities to produce carbon dioxide gas when grown on galactose. The selected strain, No. 9 and the reference strains NRRL Y-1528 which was exceptionally resistant to high concentration of substrate, were acclimated on sugars such as glucose, mannose, and galactose, and then their ethanol productivities were investigated during fermentation on these three carbon sources. Ethanol productivity of the strain No. 9 reached to the maximum levels after 18 h of fermentation and the ethanol yield was from 36 to 38% when presented as $[EtOH]_{max}/[Sugar]_{ini}(g/g)$, regardless of the conditions of acclimation. From the results obtained by acclimation and fermentation, it was concluded that the ethanol yields from galactose were not affected by the sugars acclimated. Improvements of the strain S. cerevisiae No. 9 were attempted to increase the fermentation efficiency and/or ethanol yields on high concentration of substrate by the conventional mutation methods employing methanesulfonic acid, ethyl ester (EMS). Mutants, Mut-5 (SJ1-40), -17 (LK4-25) and -24 (LK2-48) fermented galactose at the concentration of 20% in the levels of higher 39.9~51.6% than the mother strain, No. 9, however, their ethanol yields never exceeded those of the reference strain.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.541-546
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• 1992

In order to develop low salt fermented hen clam sauce with high stability, the effects of citric acid pretreatment and fermentation temperature were examined. The VBN contents of surf clam sauce treated with citric acid (SCA) were lower than those of control and the same sauces added alcohol at two temperature conditions ($5^{\circ}C$ and room temperature) during fermentation. The maximum $NH_2-N$ contents of control and SCA during fermentation at $5^{\circ}C$ were 501.3 and $618.4{\sim}691.6\;mg/100g$, respectively, and the pH of those showed $5.61{\sim}6.24$ and $2.43{\sim}3.21$. The total creatine contents of control and SCA, respectively, were $36.8{\sim}27.6\;mg/100g$ ranges. As the time of treatment with citric acid was longer, the degradation of ATP, ADP and AMP in the SCA was faster. In the control, the Ala content was $19.6{\sim}23.02%$ and was highest level among all free amino acids. As fermenting term was longer, among the free amino acids, Ala and Gly were large amounts in control and SCA, respectively, and Gly was slowly increased in SCA during fermentation. As the results of organoleptic test, the tastes of SCA showed good score than control.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.179-185
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• 2018

In this study, the optimal fermenting conditions of sugar extracts of Artemisia annua L. (Aa), Houttuynia cordata Thunb (Hc), and Saururus chinensis Baill (Sc) were determined to develop fermented beverages. The sugar extracts ($50{\pm}5^{\circ}Bx$) were diluted to 10, 15, and $20^{\circ}Bx$, and fermented with 2% (v/v) of Lactobacillus plantarum DK119 ($5{\times}10^9CFU/mL$) at $37^{\circ}C$ for 4 days. According to the lactic acid bacteria population, pH, titratable acidity, and reducing sugar content, $20^{\circ}Bx$ for Aa, $10^{\circ}Bx$ for Hc and $15^{\circ}Bx$ for Sc were the maximum concentrations for the fermentation. There were no changes in total polyphenol content in the extracts of Aa, Hc, and Sc, whereas the radical scavenging activity and ferric reducing antioxidant power were increased during the fermentation. Lactic acid fermentation resulted in improvement of sensory evaluation scores on unfavorable plant taste and overall acceptability of the sugar extracts of medicinal plants.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.259-265
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• 2015

Momordica charantia, commonly known as bitter melon, has interesting pharmacological activities such as anticancer, antiviral, antibacterial, anti-inflammatory, analgesic, and antioxidant. As supported by recent scientific reports on the beneficial effects of M. charantia, it is one of the most promising functional plants for diabetes today. In this study, we fermented the bitter melon with lactic acid bacteria and investigated the capability of controlling diabetic conditions by decreasing the blood glucose levels. After extracting the fermented bitter melon with hot water or ethanol, we tested several biological activities using mouse models. When we tested the efficacy of the glycemic control, the extracts of fermented bitter melon significantly lowered the blood glucose levels of the alloxan-induced diabetic mice. We also found that the lactic acid bacteria-fermented bitter melon protected liver damages from the treatment of alloxan monohydrates and maintained low levels of triglycerides and high levels of HDL cholesterol in these mouse models. These results suggest that our approach on fermenting bitter melon and the extracts of fermented bitter melon could lead to the possibility of the development of functional foods that contain the effectiveness of controlling blood glucose and lipid levels as well as preventing liver damages.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.283-289
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• 2002

This study was performed to search for potential microorganism that has rapid fermenting and physiological function from anchovy sauce. We isolated three bacterial strains, JM-1, JM-2, and JM-3 with proteolytic and fibrinolytic activity from anchovy sauce. Among the 3 bacterial strains, JM-3 showed the strongest proteolytic and fibrinolytic activity. Bacterial strain JM-3 was gram-positive rod, motile and formed endospore. The 16S rRNA of bacterial strain JM-3 was amplified by PCR and then its sequence was determined by ABI 310 genetic analyzer. The 16S rRNA sequence of bacterial strain JM-3 was compared to BLAST DNA database and identified to Bacillus subtilis with 99% of homology. The optimum temperature, pH and NaCl concentration for growth of B. subtilis JM-3 were $40^{\circ}C$, 5.0 and 0%, respectively. The optimum temperature, pH and NaCl concentration for proteolytic and fibrinolytic enzyme production of B. subtilis JM-3 were same as optimum conditions for growth. At 20% of NaCl concentration which is common NaCl concentration of fish sauce, B. subtilis JM-3 showed about 60% of proteolytic and fibrinolytic activity of 0% NaCl concentration. From above results, we found that B. subtilis JM-3 will be able to used for starter of functional fish sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.719-725
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• 2014

This study was investigated for the purpose of obtaining basic data for application to the canning process of salt-fermented anchovy Engraulis japonica fillet using tomato paste. The salt fermented anchovy fillet was prepared by fermenting anchovy fillet with salt 15% at $5^{\circ}C$ for 15 days and then cold air drying the salt-fermented anchovy fillet for 1 h at $16{\pm}1^{\circ}C$. The dried salt-fermented anchovy fillet 85 g was filled with 60 g of tomato paste sauce (tomato paste 42%, gum guar 1.0%, salt 2.0%, starch syrup 2.0%, cooking wine 1%, water 52%) and seamed by vacuum seamer in 301-3 can, then sterilized at Fo 9 and 11 min in a steam system retort at $121^{\circ}C$, respectively. The factors such as chemical composition, pH, total volatile basic nitrogen (TVB-N), amino-N, color value (L, a, b), texture profile, thiobarbituric acid (TBA) value, sensory evaluation and viable bacterial count of the canned salt-fermented anchovy fillet were measured. Texture value of the product sterilized at Fo 11 min was higher than at Fo 9 min condition. In both sterilized cans, the viable bacterial counts were not detected. There was no remarkable difference in physicochemical between sterilization conditions. As a result of sensory evaluation, most sensory evaluation inspector judged that it was difficult to distinguish the sensory difference of both products sterilized at Fo 9 min and at 11 min. The results showed that sterilization of Fo 9 min was more desirable than that of Fo 11 min to prepare canned salt-fermented anchovy fillet using tomato paste sauce, because this condition is more economical.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.11-11
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• 2015

A total of sixty-six samples of Nuruk, a fermention starter used to make the Korean traditional rice wine, Makgeolli, were collected from central and southern regions of Korea in 2013 and 2014. We classified two groups of the Nuruk samples, "commercial" and "home-made", according to the manufacturing procedure and purpose of use. Commercial Nuruks were made in a controlled environment where the temperature and humidity are fixed and the final product is supplied to Makgeolli manufacturers. Home-made Nuruks were made under uncontrolled conditions in the naturally opened environment and were intended for use in the production of small amounts of home-brewed Makgeolli. We obtained more than five hundred isolates including filamentous fungi and yeasts from the Nuruk samples followed by identification of fungal species. Also we stored glycerol stocks of each single isolate at $-70^{\circ}C$. We identified the species of each isolate based on the sequences of ITS regions amplified with two different universal primer pairs. We also performed morphological characterization of the filamentous fungi and yeast species through observations under the microscope. We investigated the major fungal species of commercial and home-made Nuruks by counting the colony forming units (CFU) and analyzing the occurrence tendency of fungal species. While commercial Nuruks contained mostly high CFU of yeasts, home-made Nuruks showed relatively high occurrence of filamentous fungi. One of the representative Nuruk manufacturers used both domestic wheat bran and imported ones, mainly from US, as raw material. Depending on the source of ingredient, the fungal diversity was somewhat different. Another commercial Nuruk sample was collected twice, once in 2013 and again in 2014, and showed different diversity of fungal species in each year. Nuruks obtained from the southern regions of Korea and Jeju island showed high frequency of yeast such as Saccharomycopsis fibuligera and Pichia species as well as unique filamentous fungus, Monascus species. S. fibuligera was easily found in many Nuruk samples with high CFU. The major filamentous fungi were Aspergillus, Lichtheimia, Mucor and Penicillium species. In order to further our understanding of the isolates and their potential industrial applications, we assayed three enzymes, alpha amylase, glucoamylase and acid protease from 140 isolates out of about five hundred isolates and selected about 10 excellent strains with high enzyme activities. With these fungal isolates, we will perform omics analyses including genomics, transcriptomics, metabolic pathway analyses, and metabolomics followed by whole genome sequencing of unique isolates associated with the basic research of Nuruk and that also has applications in the Makgeolli making process.

• Journal of Life Science
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• v.20 no.3
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• pp.403-410
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• 2010

In order to produce high-quality fermenting composts, a microorganism was isolated from the natural world. The bacterium has not only in high enzyme activities but also had good antimicrobial activities against phytopathogenic microorganisms. Its cultivating characteristics were then investigated. Bacterium KJ-9, which contains high CMCase, protease and chitinase activities and excellent antimicrobial activities against phytopathogenic microorganisms, was separated from leaf mold and identified as Bacillus licheniformis by two methods: Bergey's Manual of Systematic Bacteriology and API 50 CHL Carbohydrate Test Kit (Bio Merieux, France) using an ATB (Automated Identification) computer system (Bio Merieux, France). Optimal medium for cultivation of B. licheniformis was 2% soluble starch as a carbon source, 0.5% yeast extract as a nitrogen source and 0.05% $MgSO_4{\cdot}7H_2O$. Optimal growth conditions of pH, temperature and shake speed were pH 7.0, $50^{\circ}C$ and 180 rpm, respectively. Culture broth of B. licheniformis KJ-9 cultured for 36~60 hr was effective in fungicidal activities against plant pathogens including Botrytis cinerea, Corynespora cassicola, Fusarium oxysporum, and Rhizoctonia solani.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.630-637
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• 2022

The objective of this study was to optimize industrial-grade media for improving the biomass production of Weissella cibaria JW15 (JW15) using a statistical approach. Eleven variables comprising three carbon sources (glucose, fructose, and sucrose), three nitrogen sources (protease peptone, yeast extract, and soy peptone), and five mineral sources (K₂HPO₄, potassium citrate, ⳑ-cysteine phosphate, MgSO₄, and MnSO₄) were screened by using the Plackett-Burman design. Consequently, glucose, sucrose, and soy peptone were used as significant variables in response surface methodology (RSM). The composition of the optimal medium (OM) was 22.35 g/l glucose, 15.57 g/l sucrose, and 10.05 g/l soy peptone, 2.0 g/l K₂HPO₄, 5.0 g/l sodium acetate, 0.1 g/l MgSO₄·7H₂O, 0.05 g/l MnSO₄·H₂O, and 1.0 g/l Tween 80. The OM significantly improved the biomass production of JW15 over an established commercial medium (MRS). After fermenting OM, the dry cell weight of JW15 was 4.89 g/l, which was comparable to the predicted value (4.77 g/l), and 1.67 times higher than that of the MRS medium (3.02 g/l). Correspondingly, JW15 showed a rapid and increased production of lactic and acetic acid in the OM. To perform a scale-up validation, batch fermentation was executed in a 5-l bioreactor at 37℃ with or without a pH control at 6.0 ± 0.1. The biomass production of JW15 significantly improved (1.98 times higher) under the pH control, and the cost of OM was reduced by two-thirds compared to that in the MRS medium. In conclusion, OM may be utilized for mass producing JW15 for industrial use.

• Journal of Life Science
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• v.34 no.5
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• pp.296-303
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• 2024

Vinegar is a fermented food product created by fermenting various sugar- and starch-containing ingredients with microorganisms. It contains a variety of organic acids, sugars, amino acids, esters, and other compounds that contribute to its unique sensory properties. Vinegar is known for its potential benefits, including aiding digestion, lowering blood sugar levels, anti-obesity effects, and antioxidant properties. It is also believed to contribute to improving alkaline body conditions. This study was conducted to develop functional dried vinegar powder from naturally fermented vinegars. Unripe apple, brown rice, and black chokeberry (aronia) were fermented using Gluconacetobacter xylinus for 90-180 days. The filtrate vinegar was spray dried with 37.46% maltodextrin, 5% glucose, 1% citric acid, and 0.04% vitamin C. Analysis of the acidity, color difference, water and soluble solid content, and heat stability of dried vinegar (DV) confirmed that spray drying is a suitable method for powder production. Moreover, the DVs exhibited excellent sensory attributes and solubility. Among the DVs, aronia-DV showed the highest 1,1-diphenyl-2-picryl hydrazyl and 2,2-azobis (3- ethylbenzothiazoline-6-sulfonate) radical scavenging activity (36.7% and 75.3%) and reducing power (0.334) at 0.5 mg/ml concentration, respectively. The nitrite scavenging activity was highest in brown unripe apple-DV, followed by aronia-DV and brown rice-DV. In the anti-thrombosis activity assay, aronia-DV showed the highest prothrombin inhibition. The brown rice-DV exhibited lipid accumulation inhibitory activity in 3T3-L1 adipocytes without cell cytotoxicity. Our results suggest the potential for commercialization of dried vinegar, highlighting its diverse benefits and applications.