• Journal of Ginseng Research
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• v.4 no.2
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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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• v.13 no.1
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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.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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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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• v.11 no.3
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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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• v.15 no.5
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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.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.135-141
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• 2007

To increase the consumer acceptability of yam and the shelf-life of fresh-cut yam, organic acid-treated fresh-cut yam was prepared. When uncontaminated fresh-cut yam was stored at $4^{\circ}C$ for 14 days after treatment with 1% (v/w) organic acids, the browning and microbial putrefaction of fresh-cut yam were inhibited by treatment of acetic acid or maleic acid, whereas treatment of citric acid and ascorbic acid, commonly used browning inhibitors in food industry, did not show apparent effects on the browning and putrefaction of yam. The Inhibitory effects of acetic acid or maleic acid were superior than those of NaOCl (100 ppm), hydrogen peroxide (100 ppm) or commercially available washing solution. Also, treatments of 1% acetic acid, or 1% maleic acid Into artificially-contaminated yam $(10^5\;CFU/g-yam)$ showed strong inhibition of browning and putrefaction during long term storage at $4^{\circ}C$. The growth inhibition test indicated that 0.1% is enough to inhibit the growth of psychrotrophic yam-putrefactive Pseudomonas sp., and treatment of 0.1% acetic acid, or 0.1% maleic acid inhibited the browning and microbial putrefaction of fresh-cut yam. Our results suggested long-term distribution of yam or other root crops products is possible by treatment of organic acid, such as acetic acid, combined with aseptic vacuum packaging technology.

• Journal of Ginseng Research
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• v.4 no.2
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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.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.83-89
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• 1992

This study was perfonned to investigate effectiveness eness on the gastritis and gastric lesion with the methanol extract of the flower buds of Eugenio caryophyllata. The extract was fractionated with hexane, chIorofonn, ethyl acetate, butanol, followed by bioassay Oil antigastritis. The ethyl acetate and the buthanol fraction reduced significantly HCI.ethanol induced gastric lesion at the dose of 165 and 215 mg/kg, p.o., respectively. These results may indicate that remarkably.effective are ethyl acetate and butanol fractions in HCI-ethanol induced gastric lesion. Howeever, the fractions didn't exhibit any inhibition of gastric secretion and acid output. The buthanol fraction reduced significantly the acetic acid induced ulcer at a daily dose of 215 mg/Kg, p.o., given for 10 days. These result showed considerable inhibit of acetic acid induced ulcer without inhibition of indomethacin induced gastric lesion. The methanol extract showed low acute toxicity with minimum lethal dose of more than 3000 mg/kg, p.o. in mice. In conclusion, Eugenia F10s exhibited antigastric activity which might be attributable to inhibition of gastric secretion. It is indicated that activie component may be present in the buthanol fraction.

• Applied Biological Chemistry
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• v.28 no.1
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• pp.28-35
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• 1985

Potato tubers treated at $4^{\circ}C$ for 4 weeks were irradiated with a dose of 0.12 kGy from $^{60}Co$ source and stored at $20^{\circ}C,\;70{\sim}90%$ humidity for 5 weeks. Changes of ${\alpha}-amylase$, peroxidase, indole acetic acid oxidase, indole acetic acid synthesizing enzyme activities were determined. In addition, treatment of gibberellin or indole acetic acid to tubers irradiated were carried out to examine reversal of sprout-inhibition of tubers irradiated. Results are as follows; 1. Irradiation by ${\gamma}-ray$ at 0. 12 kGy dose inactivated easily the enzyme activities in vitro. $D_{37}$ values obtained were 0.94, 0.36 kGy for ${\alpha}-amylase$ and peroxidase, respectively 2. Complete inhibition of the toter sprouting was resulted by the irradiation of tubers with a dose of 0.12 kGy. 3. The indole acetic acid oxidase activity increased 2 times immediately after irradiation. Meanwhile, indole acetic acid synthesizing activity decreased about $50{\sim}75%$ for 5-week storage in irradiated potatoes, whereas the activity increased about 3.5 times along with sprouting in non-irradiated tubers. 4. In morphological aspects, deformed buds with necrosis in the meristmatic tissue were developed in irradiated tubers. Treatment of gibberellin or indole acetic acid at the concentration of 100 or 20 ppm to the irradiated tubers reversed the sprout-inhibition partially. Nevertheless, the deformed buds remained without change.

• KSBB Journal
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• v.14 no.2
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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.