• 약학회지
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• 제39권4호
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• pp.433-437
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• 1995

Optically pure(-)-and (+)-$\alpha$-hydroxy-$\alpha$-(p-chlorobiphenyl)acetic acids were prepared. The racemate was synthesized through three steps. By condensation of p-cnorobiphenyl with diethyl ketomalonate in the presence of SnCl$_{4}$, diethyl $\alpha$-hydroxy-$\alpha$-(p-chlorobiphenyl)malonate (1) was formed and subsequently ($\pm$)-$\alpha$-hydroxy-$\alpha$-(p-chlorobiphenyl)acetic acid (3) was obtained through hydrolysis and decarboxylation. For the separation of the racemate the classical resolution method, derivatization of a racemate by reaction with an optically pure compound was employed. In this case the optically pure compound were [R]-(+)-$\alpha$-methylbenzylamine and [S]-(-)-$\alpha$-methylbenzylamine. Diastereomeric salts between acids and bases could be easily separated by crystallization in absolute ethanol.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.44-48
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• 2002

Washing technique using solubilization and surfactant as a extractant was studied by removing contaminants from the cohesive soil contaminated with heavy metal. For this purpose, the laboratory desorption batch tests were peformed in the kaolinite contaminated with lead by using acetic acid as a solubilization and SDS as a anionic surfactant. In desorption batch tests, the effects of extractant concentration and mixing ratio were investigated and also the coupling effects of acetic acid added with surfactant were considered. Test results show that the removal efficiency of acetic acid as a extractant in the kaolinite contaminated with lead increased with increasing the concentration of acetic acid and the acetic acid was found to be more effective when adding CMC 2 or 3 of surfactant. Additionally, regardless of the initial concentration, the efficiency of lead removal from the contaminated soil increased with increasing shaking ratio.

• 한국염색가공학회지
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• 제31권4호
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• pp.268-275
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• 2019

In this study, silk fabrics was dyed with sappan wood extracts fermented for 5 and 15 days, respectively, and then the dyeability, durability and the functionality of the dyed silk were investigated. Before dyeing, the silk was pretreated with chitosan-acetic acid solution or chitosan acetic acid and illite blend solution. Thereafter, UV-Visible transmittance, color, fastness, antimicrobial activity, and the FIR emissivity were analyzed. As a result, the K/S value was higher in the samples that were not pre-treated or fermented. Regardless of fermentation, the lightfastness was not significantly different. The color fastness to washing was slightly better when the samples were pretreated with chitosan-acetic acid and illite, and then dyed with extracts fermented 5 days. In addition, all samples showed high antimicrobial activity of 99.9%, regardless of the fermentation. Far-infrared emissivity was confirmed to be slightly increased by the illite and chitosan-acetic acid solution treatment compared to the untreated sample.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.747-754
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• 1995

E. coli growth is inhibited by organic acids produced in the broth. In order to reduce the inhibition, an electrodialysis unit was used. Model solutions (acetic acid plus distilled water or M-9 medium) were tested in the unit for investigating the optimum condition of current and voltage. Electrodialysis cultures were performed with the optimum condition where the highest current efficiency could be attained. The distilled water plus acetic acid gave us a higher current efficiency than the M-9 plus acetic acid. Electrodialysis efficiently removed acetic acid and so enhanced the specific growth rate of E. coli compared with the control experiment without clectrodialysis.

• 동아시아식생활학회지
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• 제14권5호
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• pp.508-512
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• 2004

In other to produce vinegar using Schizandra chinensis Ballon(omija), acetic acid bacteria(AAB) were selected from several conventional vinegars, and total 30 acetic acid bacterial strains were isolated. Among the isolated strains, a strain was selected from medium containing omija juice which showed the highest productivity of acetic acid. The strain was identified as Acetobacter sp. C5-1b. Optimum conditions for acetic acid production of Acetabacter sp. C5-1b were involved with 30t: of fermentation temperature and shaking culture. The acidity of culture medium was reached to 5.3% after 8 days shaking cultivation at 30℃.

• 한국식품영양과학회지
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• 제21권4호
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• pp.377-380
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• 1992

To produce economically important acid with pear juice, an acetic acid bacterium was selected from many isolated acetic acid bacteria. The alcohoic fermentation was conducted by inoculating pear juice with Saccharomyces cerevisiae ATCC 4124, and then the pear vinegar was prepared by batch cultivation in flaskes with the isolated Acetobacter sp. The optimum conditions for high yield of acetic acid were studied experimentally in the batch shake flask . For seed purposes the Acetobactor sp. was cultivated for 2 -days and transferred to the acid production medium . Optimum alcohol concentration, initial acidity and temperature for the acid production were 8.0% , 2.0% and 28$^{\circ}C$, respectively. Under the same conditions, the addition of yeast extract (1%) was observed to produce relatively high yield of acetic acid.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.789-793
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• 1999

The effect of acetic acid formation deficiency on recombinant E. coli fermentation was investigated using a mutant strain deficient in acetic acid formation. A mutant strain which does not grow under anaerobic conditions was isolated. The acetic acid production in this strain was negligible in aerobic batch fermentation. The cloned-gene expression in the mutant strain was higher than the wild-type strain. Fed-batch fermentations with controlled specific growth rates were carried out in order to compare the cloned-gene expression between the wild-type and the mutant strains. The expression decreased along with the specific growth rate in both strains. The cloned-gene expression in the mutant strain was 60% higher than in the wild-type strain at the same specific growth rate.

• Journal of Ginseng Research
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• 제4권2호
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• pp.121-132
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• 1980

In order to study the effect of Korean ginseng (Panax ginseng C. A. Meyer) components on acetic acid fermentation, ginseng extracts, sucrose, total can de saponins were added to the basal niedium respectively and surface culture was carried out at 30$^{\circ}C$. Lag ime, total acidity of the fermentation broth inhibitors and the degrees of inhibition were determined in tile course of fermentation . 1. Acetic acid fermentation was not inhibited by the addition of less than 1.93% of sucrose but the degree of inhibition was increased slightly by the addition of sucrose more than that. 2. Ginseng extract inhibited acetic acid fermentation slightly, and the degree of inhibition was similar to that of sucrose. Lag time was about 72 hours when a 20% of ginseng extract was added to the basal medium while that of the control was 22hours. 3. The free saponins inhibited acetic acid fermentation considerably, and the degree of inhibition of the saponins was about 400 folds of that of ginseng extracts. An increase of total acidity of the broth which contained 2.905% of the saponins was not observed even after one month. 4. It was presumed that some other components except saponins and sucrose in ginseng extracts counter the inbition effect of saponins on acetic acid fermentation

• 한국식품영양과학회지
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• 제32권4호
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• pp.544-548
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• 2003

매실을 사용하여 초산을 생산하기 위하여 알콜 농도, 발효온도, 당 농도의 3변수와 5수준의 fractional factorial design에 의하여 RSM computer program을 사용하여 최적 발효조건을 조사하였다. 초산함량에 대한 회귀분석결과, $R^2$는 0.9462로 높게 나타났다. 알콜 농도 8.76%, 발효 온도 26.27$^{\circ}C$, 당농도 8.42%에서 발효하는 것이 초산 생성을 위하여 가장 양호하였으며, 이 조건에서의 초산 생성 예상치는 3.23%이었다.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.96-101
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• 1998

여러 가지 외부 탄소원(acetic acid, glucose, methanol, molasses)으로 활성 슬러지를 이용하여 탈질 효과를 살펴보았다. 질산성 질소와 아질산성 질소를 질소원으로 하는 혐기성 슬러지의 회분식 배양을 통해 탈질속도, COD 소비, 탈질율을 조사해 본 결과 molasses는 탈질속도나 COD 소비에서 glucose와 비슷하고 acetic acid나 methanol보다 높았으나, 탈질 효율에 있어서는 질산성 질소나 아질산성 질소배지에서 30-40%가 암모니아로 축적되어 탈질 효율이 떨어졌다. 이러한 현상은 molasses와 glucose를 탄소원으로 이용한 경우 발효에 의해 pH저하를 초래하고 이로 인해 탈질 효율이 감소되는 것으로 생각된다. 따라서 초기 pH를 조절하고 외부 탄소원은 molasses를 이용, 탈질 효과를 조사한 결과 pH 8일 때 암모니아의 축적은 거의 없었으며 탈질 속도에 있어서도 acetic acid의 경우보다 12시간정도 빠른 24시간 안에 99% 이상 탈질 효율이 증가함을 알 수 있었다.