• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.173-176
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• 2001

This report concerns the role of indole-3-acetic acid (IAA) in bacterial pustule disease of soybean. Pustule production in soybean leaves caused by Xanthomonas axonopodis pv. glycines was accompanied by a drastic increase in IAA content of host tissues. The phytopathogenic bacterium synthesized IAA in a tryptophan concentration-dependent manner when grown in a defined minimal medium. In complex media, however, the pathogen showed no response to tryptophan feeding, implying that the bacterial biosynthetic machinery of IAA is strictly regulated by nutrient availability of its growth environments. The results may suggest that IAA of bacterial origin and tryptophan of plant origin be involved in the process of pustule symptom development in soybean.

• Journal of Microbiology and Biotechnology
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• v.3 no.4
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• pp.266-269
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• 1993

The production of free non-volatile and volatile organic acids in Kimchi during fermentations at 30, 20 and $5^{\circ}C$, were determined by gas chromatography. The order in the amount of non-volatile organic acid, soon after preparation, was malic, citric, tartaric, pyroglutamic, oxalic, lactic, succinic and ${\alpha}-ketoglutaric$ acids. The major non-volatile acids at the optimum ripening time were malic, tartaric, citric and lactic acids, and as the temperature was lowered, the amount of lactic, succinic, oxalic, pyroglutamic and fumaric acids increased, while that of malic and tartaric acids decreased. The order in the amount of volatile acids at the beginning was acetic, butyric, propionic and formic acids. Among these acids, acetic acid was significantly increased in its amount during fermentation and the Kimchi fermented at low temperature produced more acetic acid than that fermented at high temperature.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.343-348
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• 1989

Production of shikonin derivatives by Lithospermum erythrorhizon cells by using polyurethane foam was invesliigated. Shikonin derivatives were effectively adsorbed mostly by phase distribution to polyurethane matrices and their production increased significantly compared to the suspension culture. The enhanced production of shikonin was probably due to more facilitated cell to cell con-tact and lowered intracellular shikonin concentration, both of which are known to be favorable for plant secondary metabolite production. In order to improve the process productivity, tell culture was conducted under various culture conditions: Of them, Schenk and Hildebrandt medium containing indole-3-acetic acid (1.75mg/ι) and kinetin (0.1mg/ι) was considered most appropriate for shikonin production. Production of shikonin increased about 4.5 times in the Schenk and Hildebrandt medium containing indole-3-acetic acid (1.15mg/ι) and kinetin (0.1mg/ι) when compared to the same medium containing p-chlorophenoxyacetic acid (2.0mg/ι) and kinetin (0.1mg/ι). When poly-urethane was used as the support material, a single-stage system was more preferred to the conventional two-stage culture system in terms of shikonin productivity.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.204-208
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• 2006

Soybean sprout decay during its culture should be one of serious problems. The study was carried out to clarify the effect of water imbibition and acetic acid treatments on growth and morphological characters of the soybean sprouts. The soybean seeds of 3 cultivars (cv. Eunhakong, Pungsannamulkong and Junjery) imbibed in pure water or 0.l% acetic acid for 3 minutes before soaked for 6 hours into 1 ppm BA solution and aerated for 3 hours immediately before 6 day culture. On the 6th day, the sprouts were classified into 4 categories on the base of hypocotyl length; > 7cm, 4 to 7cm, > 4cm and not germinated and seed floating rate, their morphological characters, fresh fraction weights and productivity were measured. The best water imbibition for seed cleaning was to soak the seeds for 5 minutes and then to aerate soak them for 40 minutes. In Pungsannamulkong and Junjery, percentage of the sprouts with hypocotyls of longer than 4 cm was higher in water imbibition than in acetic acid treatment for seed disinfection although in Eunhakong there was no significant difference between the two treatments. Eunhakong and Junjery had greater lateral root formation rate and its number per sprout in water imbibition than in acetic acid treatment but Pungsannamulkong showed reverse result. Eunhakong and Pungsannamulkong, furthermore, had more total fresh weight in acetic acid treatment than in water imbibition but Junjery showed reverse result, although there was no significant difference between the two treatments in productivity of mass production system.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.189-194
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• 2013

In a study of hydrogen-producing bacteria, strain T4384 was isolated from rice field samples in the Republic of Korea. The isolate was identified as Enterobacter sp. T4384 by phylogenetic analysis of 16S rRNA and rpoB gene sequences. Enterobacter sp. T4384 grew at a temperature range of $10-45^{\circ}C$ and at an initial pH range of 4.5-9.5. Strain T4384 produced hydrogen at 0-6% NaCl by using glucose, fructose, and mannose. In serum bottle cultures using a complete medium, Enterobacter sp. T4384 produced 1,098 ml/l $H_2$, 4.0 g/l ethanol, and 1.0 g/l acetic acid. In a pH-regulated jar fermenter culture with the biogas removed, 2,202 ml/l $H_2$, 6.2 g/l ethanol, and 1.0 g/l acetic acid were produced, and the lag-phase time was 4.8 h. Strain T4384 metabolized the hydrolysate of organic waste for the production of hydrogen and volatile fatty acid. The strain T4384 produced 947 ml/l $H_2$, 3.2 g/l ethanol, and 0.2 g/l acetic acid from 6% (w/v) food waste hydrolysate; 738 ml/l $H_2$, 4.2 g/l ethanol, and 0.8 g/l acetic acid from Miscanthus sinensis hydrolysate; and 805 ml/l $H_2$, 5.0 g/l ethanol, and 0.7 g/l acetic acid from Sorghum bicolor hydrolysate.

• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.69-72
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• 1997

The pH of microbial culture medium was calculated from equations of equilibrium, meterial balances for ionic components and electro-neutrality theory. Ammonium ion consumption and Acetic acid production are found out to be the major contributors for the alteration of the pH as well as the buffer capacity of the medium. By measuring the buffer capacity on-line, levels of acetic acid were estimated by a software sensor using pH signal in a fermentation process of E.coli growing in a minimal medium. The measured values of acetic acid showed good correlation to those of estimated by the software sensor.

• Journal of Plant Biology
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• v.34 no.4
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• pp.325-330
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• 1991

The ability of several auxin analogs to induce ethylene production was tested in the corn coleoptile. The synthetic auxins 1-naphthaleneacetic acid (1-NAA) and 2, 4-dichlorophenoxyacetic acid (2, 4-D) had strong stimulatory effects on ethylene induction surpassing that of IAA. Both 2-naphthalaneacetic acid (2-NAA) and 2, 6-dichlorophenoxy acetic acid (2, 6-D), structural analogs of these auxins, respectively, were found to be inactive. Treatment with NPA, a strong inhibitor of polar auxin transport, led to drastic increase in IAA-induced ethylene production while it has bo effect on ethylene production induced by 1-NAA. A positive correlative existed between intracellular auxin level and ethylene production.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.252-256
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• 2013

We tested the possibility of utilizing Korea domestic wheat (winter wheat variety "keumkangmil") as a source of vinegar production. After saccharification of the whole-wheat flour with wheat malt, the saccharized liquid undergoes alcoholic fermentation, followed by acetic fermentation. Acetic acid bacterium A8, which showed the highest acetic acid production (4.56%) with domestic wheat as substrate, was selected from conventional vinegars. The strain A8 was identified as Acetobacter pasteurianus A8 through phylogenetic study using 16S rDNA sequencing analysis. The optimal condition for the malt enzyme was found to be $15^{\circ}C$ for germination periods of 6 days; its amylase activity was 608.4 U. Acetic acid production from domestic wheat substrate supplemented with 5% ethyl alcohol reached 5.8% after 24 days of static fermentation at $30^{\circ}C$ with a seeding rate of 5%.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.381-385
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• 2006

The production of astaxanthin by Xanthophyllomyces dendrorhous mutant depended on the culture conditions. Therefore, a cultivation strategy, including effective chemical and light induction, for the high-level production of astaxanthin by X. dendrorhous mutant JH1 was explored. Effective chemicals such as ethanol, acetic acid, and hydrogen peroxide, which are known inducers or precursors of astaxanthin synthesis, were investigated for their increase of astaxanthin production. Each of 1.0% ethanol, 1.0% acetic acid, and 1.0% hydrogen peroxide increased the astaxanthin concentration to 49.77 mg/l, 46.33 mg/l, and 45.61 mg/l, respectively. Among these chemicals, 1.0% ethanol showed the best effect on increasing astaxanthin concentration after 48 h of cultivation. Under 1.0% ethanol feeding condition, high light intensity (2,400 lux) stimulated astaxanthin production to 59.67 mg/l, compared with that in the dark-grown cultivation.

• KSBB Journal
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• v.10 no.4
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• pp.455-460
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• 1995

Specific growth rate was controlled for the repression of acetic acid formation in the fed-batch fermentation of recombinant Escherichia coli. With controlled specific growth rate, we studied the effect of the specific growth rate on cell growth, glucose consumption, acetic acid formation, and the expression of recombinant protein (${\beta}$-lactamase). High specific growth rate caused the accumulation of glucose and acetic acid, and lowered the production of recombinant protein. However, the addition of methionine recovered the gene expression by alleviating the negative effect of acetic acid at high specific growth rate.