• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.181-185
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• 2005

We investigated the fermentative production of lactic acid from cheese whey and corn steep liquor as cheap raw materials using Lactobacillus sp. RKY2 to reduce the manufacturing cost of lactic acid. Lactic acid yields were obtained at more than 0.98 g/g from medium containing whey lactose. Lactic aid productivities and yields obtained from whey lactose were slightly higher than those obtained from pure lactose. The final concentration of lactic acid increased with increase, in whey lactose concentration, whereas the lactic acid productivity decreased probably due to substrate inhibition. The fermentation efficiencies were improved by addition of more corn steep liquor to the medium.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.297-300
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• 2000

Succinic acid was produced by Enterococcus faecalis RKY1 cells immobilized in hollow fiber bioreactor as an alternatively immobilized culture in bioconversion of fumaric acid to succinic acid. The feed was pumped through the shell side. As the flow rate of the feed was increased, the steady state was obtained more quickly. The steady state was reached after 24 hr cultivation in 0.25 ml/min, 12 hr in 0.5 ml/min, and 9 hr in 1.0 ml/min, respectively. The effect of medium pH on succinate production was also investigated. By changing the medium pH of 8.0, the succinic acid produced was increased about 16% than that of pH 7.0.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.337-341
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• 2001

This study was carried out to screen the effective polymeric additives preventing wall growth during mycelial submerged cultivation of Ganoderma. lucidum. Effects of additives on mycelial growth and exo-polysaccharide (EPS) production in flask culture and jar fermenter system under 3 different pH processes were investigated, and changes of mycelial morphology were also examined. From flask culture of G. lucidum with additives of different concentrations, 0.1%(w/v) polyacrylic acid was effective for EPS production. As the polyacrylic acid of 0.1%(w/v) was added in medium, wall growth of G. lucidum mycelium grown in jar fermenter system could be protected. The addition of 0.1%(w/v) polyacrylic acid to medium was also improved the mycelial growth and EPS production in the later of submerged culture G. lucidum and no changes of mycelial morphology were observed.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.352-358
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• 1995

In this study, authors investigated the cadmium tolerance, the accumulation of cadmium, and the cellular distribution of accumlated cadmium in lactic acid bacteria under the anaerobic condition. Lactic acid bacteria grew fairly well in modified EG medium containing 10 ppm of cadmium but could hardly grow at 50 ppm of cadmium. Tolerance to cadmium of genus Lactobacillus was greater than that of genus Streptococcus, and Lactobacillus acidophilus showed the higest cadmium tolerance amomg the bacteria tested. The capacity of cadmium accumlation (9.304-12.428 mg/g wet cell) of lactic acid bacteria was higher than that (6.775 mg/g wet cell) of Escherichia coli. Lactobacillus casei of them took up the largest amount of cadmium. The cadmium elimination amount (28.46-29.25%) of lactic acid bacteria from modified EG medium containing cadmium were also higher than that (14.43%) of Escherichia coli. Accumulated cadmium in Lactobacillus acidophilus was distributed by 42.41% at cell wall, 28.97% at cytoplasm, and 28.62% at plasma membrane, respectively.

• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.95-101
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• 1988

In order to produce lactic acid and calcium lactate very useful for foods and medical supplies, lactic acid fermentation was studied by Lactobacillus sporogenes, a spore forming lactic acid bacterium. When this bacterium was cultured aerobically in the spore forming medium, the spore forming rate was 96.0% as total cell number 20$\times$108/ml, spore number 19.2$\times$108/ml. One minute agitating every 1 hour in the flask culture, or agitation of 100rpm in the fermenter was most efficient to continue to ferment at 45$^{\circ}C$ for 4days in the fermentation medium containing 10% glucose as carbohydrate and CaCO3 as a neutralizing agent. This homofermentative lactic acid bacterium showed fermentation yield of 99.3% and more than 98.2% of the yield was L(+)-lactic acid.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.838-843
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• 2005

When ingredients of Kimchi were mixed and stored in $18^{\circ}C$, lactic acid bacteria, such as Leuconostoc mesenteroides and Lactobacillus plantarum, were selectively grown up. Herefore, to understand why lactic acid bacteria were selectively cultured in Kimchi, antibacterial activities of Kimchi ingredients against some pathogens and Kinlchi lactic acid bacteria were investigated. Kimchi mixed with all ingredients significantly inhibited the growth of all tested pathogens: S. typhimurium, S. sonnei, and E. coli. Kimchi without green onion, garlic or ginger inhibited the growth of S. typhimurium, but did not E. coli and S. sonnei. However, Kimchi without red pepper powder did not inhibit the growth of all tested pathogens. All ingredients of Kimchi did not inhibit the growth of L. plantarum and L. mesenteroides. These results suggest that Kimchi ingredients can synergistically inhibit the growth of pathogens and Kimchi may be a selective medium for lactic acid bacteria.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.172-176
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• 2006

In order to increase the productivity of lipstatin by Steptomyces toxytricini, the effect of medium components on the lipstatin production was investigated. Using TSB medium as a basal medium, a variety of carbon sources, nitrogen sources, lipid and fatty acids was supplemented into a fermentation medium. The seed culture of S. toxytricini grown in 25 ml TSB medium at $28^{\circ}C$ for 3 days with agitation at 200 rpm was inoculated in the size of 2% in fermentation media containing different components and fermented at $28^{\circ}C$ for 60 more hrs. In the examination of the effect of carbon sources, the best cell growth was observed in fermentation media supplemented with glucose or glycerol, but the lipstatin productivity was the highest in media containing lactose or sucrose. Among complex nitrogen sources, yeast extract was the best one for cell growth, but the highest lipstatin production was found in TSB media composed of 1.7% casitone and 0.3% soytone. The increased concentration of triolein as a lipid caused the promotion of cell growth but the significant suppression of lipstatin production. When 0.5% fatty acids were supplemented to fermentation medium, unsaturated fatty acids like linoleic or oleic acid suppressed cell growth as well as lipstatin production, but 2 times higher lipstatin production was achieved by stearic acid, a saturated fatty acid, differently from expectation.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1327-1332
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• 2004

The hemA gene encoding 5-aminolevulinic acid synthase (ALAS) was cloned from Rhodobacter capsulatus, and its nucleotide sequence was determined. DNA sequencing data revealed one open reading frame coding for a protein with 401 amino acids that displayed high similarity to the amino acid sequences of other known ALASs. The hemA gene was then cloned and expressed under the control of constitutive promotor in E. coli. The recombinant E. coli strain was able to accumulate 5-aminolevulinic acid to 21 mM in the liquid medium supplemented with 45 mM glycine and 120 mM succinate. In addition, a marked effect of the pH of the culture medium on ALA production was observed, and the optimum pH for culture medium was determined to be 5.8-6.3.

• New & Renewable Energy
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• v.17 no.3
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• pp.8-15
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• 2021

In this study, we assessed the effect of vitamin components (such as biotin, thiamine-HCl, and folic acid) on microorganism microbial growth and ethanol production was examined to enhance increase the ethanol concentration in the Clostridium autoethanogenum culture process using syngas as a sole carbon source. Biotin and folic acid concentrations of 0.2, 2, 20, and 100 ㎍/L were used in the culture experiments at 0.2, 2, 20, and 100 ㎍/L concentrations. The maximum ethanol concentrations of 2.81 g/L and 3.12 g/L were obtained by adding at 0.2 ㎍/L biotin and folic acid, respectively. Moreover, Thiaminethiamine--HCl at concentrations of 0.5, 5, 50, and 250 ㎍/L were was examined evaluated to in the culture experiments. The maximum ethanol concentration of 2.84 g/L was observed at 0.5 ㎍/L of thiamine--HCl. As a resultThus, the optimized concentrations of biotin, thiamine--HCl, and folic acid were determined at 0.2, 0.5, and 0.2 ㎍/L, respectively, for enhancing increasing the ethanol production. In conclusion, the maximum ethanol production was obtained by adding the minimal concentration of vitamins in C. autoethanogenum culture.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.230-239
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• 2022

Holostemma annulare (Family Asclepiadaceae) is an invaluable vulnerable medicinal plant; the root tubers are used in Ayurveda medicine and by folk healers to treat various ailments. In this study, Schenk and Hildebrandt medium fortified with the cytokinins 6-benzyl adenine, kinetin, and auxins, including indole 3-butyric acid, indole 3-acetic acid, α-naphthaleneacetic acid, and 2,4-dichlorophenoxyacetic acid, were checked for their efficiency on root tuber induction from different explants. Adventitious root tubers were more successfully induced from in vitro leaf segments and shoots when cultured in Schenk and Hildebrandt medium supplemented with 0.5 mg/l of α-naphthaleneacetic acid. In addition, preliminary phytochemical analysis of in vitro root tubers and identification of different secondary metabolites were conducted. Thin layer chromatography and high performance thin layer chromatography analysis of the crude methanolic extracts of the in vitro root tuber identified the presence of lupeol, a bioactive triterpene. Adventitious root tuber induction offers a novel method for the in vitro production of bioactive metabolites that can be scaled up by bioreactors, thus ensuring the conservation and sustainable utilization of H. annulare. The study warrants further scale-up production and pharmacological investigation that can be extended for pharmaceutical needs.