• 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

• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.90-98
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• 2003

In vivo $^31p$ Nuclear Magnetic Resonance ($^31p$NMR) and metabolic studies were carried out on an acetic acid tolerant mutant, Zymomonas mobilis $ZM4/Ac^R$, and compared to those of the parent strain, Z. mobilis ZM4, to evaluate possible mechanisms of acetic acid resistance. This investigation was initiated to determine whether or not the mutant strain might be used as a suitable recombinant host far ethanol production from lignocellulose hydrolysates containing various inhibitory compounds. $ZM4/Ac^R$ showed multiple resistance to other lignocellulosic toxic compounds such as syringaldehyde, furfural, hydroxymethyl furfural, vanillin, and vanillic acid. The mutant strain was resistant to higher concentrations of ethanol or lower pH in the presence of sodium acetate, compared to ZM4 which showed more additive inhibition. in vivo $^31p$ NMR studies revealed that intracellular acidification and de-energization were two mechanisms by which acetic acid exerted its inhibitory effect. For $ZM4/Ac^R$, the internal pH and the energy status were less affected by sodium acetate compared to the parent strain. This resistance to pH change and de-energization caused by acetic acid is a possible explanation for the development of resistance by this strain.

• 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.

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.418-422
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• 2001

Growth inhibition of Compylobacter jejuni ATCC 33291 was observed in the presence of various preservatives at various temperatures. The addition of ethanol (0.5% to 5%), hydrogen peroxide (0.05%), acetic acid (1%), propionic acid, benzoic acid, and sorbic acid showed strong antibacterial activities against C. jejuni at pH 5.5 or 6.5. The addition of 1% acetic acid and lactic acid were most effective at $42{\circ}C, followed by $25{\circ}C$ and $4{\circ}C$. This indicated that the inhibitory effect was temperature dependent. In the chicken model system, the practical death rate of C. jejuni in the FBP-media with 1% acetic temperatures ($4{\circ}$C$, $25{\circ}$C, and $42{\circ}$). Therefore, precaution has to be taken in the use of organic acids as a disinfectant in the chicken slaughterhouse.

• KSBB Journal
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• 제15권5호
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• pp.458-463
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• 2000

Production of acetic acid from cellulosic biomass by Simultaneous Saccharification and Extractive Fermentation (SSEF) was investigated. The homoacetate organism used in this study was a strain of Clostridium thermoaceticum, ATCC # 49707. A batch operation of Simultaneous Saccharification and Fermentation(SSF) using ${\alpha}$-cellulose at pH 5.5 and 55$^{\circ}C$ yielded 40% conversion of cellulose to acetic acid, while a fed-batch SSF operation produced a maximum acetic acid concentration of 25 g/L, with 50% overall yield. In-situ extractive fermentation to reduce the end-product inhibition on both bacteria and enzyme was carried out. in a batch SSEF using 200 g/L IRA-400 resin, acetic acid concentration reached to 23.9 g/L and acetic acid yield and productivity were observed to be 48% and 0.20 g/L-hr, respectively.

• 한국미생물·생명공학회지
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• 제35권2호
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• pp.135-141
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• 2007

생마의 이용성과 저장성을 증대시키기 위해, 유기산을 처리한 생마 신선편이 제품을 제조하였다. 저온 부패미생물의 초기오염이 없는 생마 신선편이의 경우, 1% 농도의 초산, 구연산, 말레산 및 아스코르빈산을 각각 처리한 후 $4^{\circ}C$에서 14일간 저장한 경우, 구연산 및 아스코르빈산 처리구에서는 갈변 및 부패가 유의적으로 진행되었으나, 초산 및 말레산 처리구에서 우수한 갈변 및 부패 억제 활성이 나타났다. 이러한 억제활성은 기존에 사용되고 있는 NaOCl(100 ppm), 과산화수소수(100 ppm) 및 1종 세척제(L사, 한국)처리보다 우수하였으며, 특히 초기 부패미생물이 $10^5\;CFU/g-yam$ 이상 오염된 신선편이의 경우에도 초산 및 말레산은 강력한 부패억제 및 갈변억제효과를 나타내었다. 생마의 저온 부패미생물(Pseudomonas rhodesiae YAM-12 및 P. cepacia YAM-10)을 대상으로 초산 및 말레산의 최소처리농도를 조사한 결과 $4^{\circ}C$에서는 0.1% 처리로 우수한 항균력이 나타남을 확인하였으며, 실제 오염되지 않은 신선편이의 경우 0.1% 처리로 유의적인 갈변 및 부패현상 없이 14일간 저온저장이 가능하였다. 이러한 결과는, 초기 저온 부패미생물의 오염이 심각하지 않은 신선편이의 경우에는, 0.1% 초산 및 말레산 처리로 $4^{\circ}C$에서 14일 장기저장이 가능함을 나타내며, 적절한 진공포장 등이 병행된다면 생마 및 근채류 신선편이 농산물의 장기간 저온 유통이 가능할 것으로 판단된다.

• Journal of Ginseng Research
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• 제4권2호
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• pp.133-145
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• 1980

In order to find out the inhibitors of acetic acid fermentation in Korean ginseng (Panax Sin son C. A. Meyer), total aglycone, panaxadiol, panaxadiol, oleanolic acid and ${\beta}$ -sitosterol were added to the basal medium, respectively, and a surface culture was carried out at 30$^{\circ}C$. The results were as follows: 1 . Saponins lost their activity to inhibit the acetic acid fermentation by hydrolysis. 2 Panaxadiol inhibited slightly, and the degree of inhibition was about 1/300 of that of free saponins. 3. Panaxadiol and oleanolic acid inhibited silighly similar to total aglycone. 4. Acetic acid fermentation was stimulated at the early stage when ${\beta}$-sitosterol was added to the media below the level of 0.000815%. But the fermentation was inhibited when media contained it more than that media 5. An over-oxidation of acetic acid was observed when the media contained total aglycone. panaxadiol, panaxatriol, oleanolic acid and ${\beta}$-sitosterol, respectively, while the media which contained sucrose, ginseng extracts ginseng saponins was shown not to be over-oxidized.

• 한국식품위생안전성학회지
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• 제7권2호
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• pp.83-89
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• 1992

정향의 mathanol 추출물로 HCI-ethanol 위손상 실험을 하여 그 방어 효과를 확인하고 이를 계통 분획한 후 각 분획에 대한 HCI-ethanol 위손상실험, 기초위액 분비실험, indomethancin 위손상실험, acetic acid 궤양 실험을 하여 추출물에 대한 급성독성과 급.만성위염 및 위손상에 대한 실험한 바 다음과 같은 결과를 얻었다. (1) $LD_{50}$은 경구투여시 3000 mg/Kg 이사이었다. (2)HCL.ethanol 위손상실험에서 EtOAc fr. 165mg/Kg과 BuOH fr. 215mg/Kg에서 손상의 크기를 유의성있게 감소시켰다. (3) Acetic Acid 궤양 실험에서 위궤양의크기가 BuOH 분획 215mg/Kg으로 유의성 있게 감소되었다. 이상의 결과로서 생각은 급만성 위염 및 위손상에 대한 세포보호 작용이 있으며 그 작용기전은 위액분비의 억제작용에 인한 것이며 그 유효성분은 대부분 butanol 분획에 존재하는 것으로 생각된다.

• Applied Biological Chemistry
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• 제28권1호
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• pp.28-35
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• 1985

방사선 조사에 의한 발아 억제기작을 살펴보기 위하여 $4^{\circ}C$ 에서 저온 처리 한 감자에 0.12 kGy 감마선을 조사한 후 5주 동안 $20{\pm}2^{\circ}C$, 상대습도 $70{\sim}90%$에서 저장하였다. 이 기간 중 발아에 관여된다고 생각되는 ${\alpha}-amylase$, peroxidase, indole acetic acid (IAA) oxidase, IAA synthesizing enzyme의 활성 변화를 추적하였다. 시판 ${\alpha}-amylase$와 peroxidase의 방사선 감수성은 0.94와 0.36 kGy의 감마선 조사하여 $D_{37}$ 값을 얻었다. 감마선 조사를 행한 감자의 IAA oxidase 역가는 조사후 급격히 증가됐고 IAA 합성 효소의 역가는 조사직후 조금 증가하였으나 저장 기간에 따라 크게 감소하였다. 형태적인 변화에서 조사된 감자에서는 성장점의 고사와 변형된 눈이 관찰되었고 IAA 흑은 gibberellin 등의 처리에 의해 이들 자체로는 회복되지 않았고 그 주위로 새로운 눈의 성장이 관찰되었다. 결론으로 방사선 조사에 의해 야기된 감자의 호흡은 탄수화물이 ${\alpha}-amylase$등의 효소에 의한 분해로 이루어져 ATP를 공급하며 뒤이은 peroxidase 역가의 증가와 같은 효소의 합성은 방사선에 의한 손상을 치유하려는 과정에 속한다 할 수 있다. 또한 눈의 생장점에서의 고사 현상은 손상에 대한 방어 작용의 일종이라 해석되며 이로인한 발아 억제 현상을 페놀 대사와 관련지어 추측할 수 있었고 증가된 IAA oxidase와 IAA 합성계의 파괴에 의한 IAA의 고갈 역시 방사선 조사에 의한 발아 억제 현상의 원인이 됨을 알 수 있었다.

• KSBB Journal
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• 제14권2호
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• pp.136-140
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• 1999

Characteristics of organic acid degradation by isolated yeast strain was investigated. Optimum initial pH was 5. Increase in cell mass was proportional to the decrease in organic acid degradation. Also no accumulation of byproduct was observed during degradation. Acetic acid degraded fast, followed by butyric acid and propionic acid in order. No significant substrate inhibition was observed up to 12 g/L of acetic acid 7 g/L of propionic acid, respectively. However, inhibition of butyric acid was significant above 4 g/L. Cell mass yield was 0.2-0.4 g cell/g acids and decreased at high decreased at high organic acid concentration. 95% of organic acid (7.5 g/L), corresponding to 13,000 ppm, was degraded in 30-40 hours.