• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.169-175
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• 1980

These studies were conducted to induce the available mutant strains in acetic acid bacteria by the irradiation of UV-light and the treatment of N-methyl-N'-nitro-N'-nitrosoguanidine. 109 strains which were capable of producing acid in the ethanol containing medium were isolated from vinegar and Kimchi collected from the region of Daejeon city. From the collection T-50 strain was identified to have a strong fermentation power and selected as a mother strain for the study. Two mutants were obtained by treating T-50 strain with UV and NTG, and these mutants had a rapid acid production in the initial stage. The study was then made to compare the basic condition for acetic acid production of the mother strain and two mutant strains. The summarized results were as follows; 1. The isolated strain (T-50) was identified as Acetobacter aceti by Bergey's manual and Acetic acid bacteria (Tokyo Univ. press). 2. The selected strain was died completely when the strain was irradiated with 15 W UV-light at a distance of 45 cm for 160 seconds. 3. The mutants such as U-48 and N-67 were rapid in the acetic acid production at the initial stage compare to the mother strain. 4. Acetic acid formation by the shaking culture method was maximized in 2 days culture, and the optimal temperature for acetic acid production was $30^{\circ}C$. 5. Acetic acid was effectively produced by the addition of 0.1% ammonium sulfate as a nitrogen source and was also produced rapidly by the addition of 0.1% glucose.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.899-905
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• 2011

In order to develop bacterial cellulose (BC) with antimicrobial activity against pathogenic microorganisms, silver and chitosan were incorporated into BC, respectively. Experiment results showed that antimicrobial activity against pathogenic microorganisms was improved with increasing silver concentration. Chitosan also showed a direct proportion between its concentration and antimicrobial activity. These results suggest that antimicrobial effects of BC using silver and chitosan are well proven to be effective. We also tested the stainability of BC with natural colorant for the application of food industry. Stainability of BC was enhanced with increasing natural colorant concentration. Decolorization of BC stained was observed by dipping it into distilled water with one hour-intervals. As a result, there was no significant difference. Combination of natural colorant-stainability and antibiosis of BC is expected to be useful in making colored antibiotic BC in various industrial application areas, considering its antimicrobial activity, high stainability and low decolorization tendency.

• KSBB Journal
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• v.32 no.3
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• pp.238-244
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• 2017

Antioxidant activities of blackberry juice and aronia juice were enhanced when fermentation was performed by acetic acid bacteria. Acetobacter pasteurianus exhibited 19.84% improvement of antioxidant activity (from $198.12{\pm}2.03$ to $237.42{\pm}7.32{\mu}mol\;TE/g$) after 12 h fermentation of blackberry juice among four acetic acid bacteria. And A. pasteurianus sub sp. Pasteurianus exhibited 9.62% improvement of antioxidant activity (from $204.25{\pm}3.98$ to $223.89{\pm}5.52{\mu}mol\;TE/g$) after 12 h fermentation of aronia juice. Metabolites of blackberry juice were analyzed to investigate the enhancement of antioxidant activity before and after fermentation. As results, Quercetin 7-(rhamnosylglucoside), nicotinic acid adenine dinucleotide, and quercetin 3-O-(6"-acetyl-glucoside) were significantly increased after fermentation by A. pasteurianus.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1304-1312
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• 2013

The effects of storage period and aerobic deterioration on the bacterial community were examined in Italian ryegrass (IR), guinea grass (GG), and whole-crop maize (WM) silages. Direct-cut forages were stored in a laboratory silo for 3, 7, 14, 28, 56, and 120 d without any additives; live counts, content of fermentation products, and characteristics of the bacterial community were determined. 2,3-Butanediol, acetic acid, and lactic acid were the dominant fermentation products in the IR, GG, and WM silages, respectively. The acetic acid content increased as a result of prolonged ensiling, regardless of the type of silage crop, and the changes were distinctively visible from the beginning of GG ensiling. Pantoea agglomerans, Rahnella aquatilis, and Enterobacter sp. were the major bacteria in the IR silage, indicating that alcoholic fermentation may be due to the activity of enterobacteria. Staphylococcus sciuri and Bacillus pumilus were detected when IR silage was spoiled, whereas between aerobically stable and unstable silages, no differences were seen in the bacterial community at silo opening. Lactococcus lactis was a representative bacterium, although acetic acid was the major fermentation product in the GG silage. Lactobacillus plantarum, Lactobacillus brevis, and Morganella morganii were suggested to be associated with the increase in acetic acid due to prolonged storage. Enterobacter cloacae appeared when the GG silage was spoiled. In the WM silage, no distinctive changes due to prolonged ensiling were seen in the bacterial community. Throughout the ensiling, Weissella paramesenteroides, Weissella confusa, and Klebsiella pneumoniae were present in addition to L. plantarum, L. brevis, and L. lactis. Upon deterioration, Acetobacter pasteurianus, Klebsiella variicola, Enterobacter hormaechei, and Bacillus gibsonii were detected. These results demonstrate the diverse bacterial community that evolves during ensiling and aerobic spoilage of IR, GG, and WM silages.

• Food Science and Preservation
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• v.24 no.5
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• pp.680-687
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• 2017

This study investigated acetic acid fermentation properties and antioxidant activity of vinegar by addition of lemon grass to develop high quality vinegar by using lemongreass. Traditional brown rice wine contained 5% lemongrass powder and had an alcohol content of 7.2%. The wine was fermented by Acetobacter. sp. RIC-V and made into lemongrass vinegar (LV). The pH and total acidity of the LV were 3.13% and 7.21%, respectively. Fructose was detected whereas glucose, sucrose, and maltose were not detected. Among organic acids, acetic acid was highest at 3658.6 mg%; trace amounts of lactic acid, citric acid, malic acid, tartaric acid, and oxalic aicd were detected. Of the 17 free amino acids, glutamic acid, histidine, alanine, and proline were mainly detected. To conduct total polyphenol content and ABTS radical scavenging activity, 3% and 5% lemongrass powder (P3LV, P5LV) and 1%, 2%, and 3% of lemongrass extract (E1LV, E2LV, E3LV) were added to LV, respectively. Total phenolics increased as the added lemongrass powder and extract increased. Total phenolics were 490.9, 559.4, and $895.7{\mu}g$ gallic acid equivalents/mL in brown rice vinegar, LV, P5LV. ABTS radical scavenging activities were 43.2%, 58.0%, and 91.0% in brown rice vinegar, LV, P5LV, respectively. These results show that lemongrass vinegar has considerable potential as a high quality functional vinegar with antioxidative effects.

• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.126-133
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• 2015

Ten types of farm-made brewing vinegars were collected and four high acetic acid-producing strains (CV1, CV3, CV5, and CV6) were isolated. Among them strain CV1, exhibiting highly alcohol-resistant and acetic acid-producing properties, was selected and its taxonomic properties were investigated by phenotypic (particularly chemotaxonomic) characterization and phylogenetic inference based on 16S rRNA gene sequence analysis. On SM broth agar, cells of strain CV1 were gram-stainingnegative and formed pale white colonies with smooth to rough surfaces. Strain CV1 produced acetate from ethanol and was resistant to up to 8% (v/v) ethanol in LM broth. Strain CV1 had a G+C content of 61.0 mol%, contained meso-DAP as the cell wall amino acid, and possessed Q-10 as the major ubiquinone. A comparison of 16S rRNA gene sequences showed that strain CV1 was most closely related to Gluconacetobacter saccharivorans (≥99.0% identity). In liquid media, the optimum growth conditions for acetic acid production were 30℃ and pH >3.0 and strain CV1 produced 9.3% and 8.4% acetic acids from 10% and 9% alcohol concentrations, respectively.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.642-647
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• 2003

In order to investigate utilization possibility of persimmon peel as a source of vinegar, we had been examined the alcohol and acetic acid fermentations of persimmon peel. In the first stage, alcohol fermentation, alcohol content was maximum value (8.22%) in 12.43 mL/g of added water, $12.41^{\circ}Brix$ of initial sugar content and 48.05 hr of fermentation time. Acidity was minimum value (0.30%) in 12.18 mL/g of added water, $13.72^{\circ}Brix$ of initial sugar content and 46.22 hr of fermentation time. In the second stage, acetic acid fermentation, acidity was maximum value (6.40%) in 2.02% of initial acidity, 67.98 rpm of agitation rate and 6.94 day of fermentation time. Browning color was minimum value in 1.50% of initial acidity, 150.0 rpm of agitation rate and 6.0 day of fermentation time. To manufacture persimmon vinegar using persimmon peel, in the first stage, optimal alcohol fermentation conditions was 12mL/g in added water, $12^{\circ}Brix$ in initial sugar concentration and 48 hr in fermentation time. In the second stage, optimal acetic acid fermentation conditions was 1.8% in initial acidity, 70 rpm in agitation rate and 6 day in fermentation time using Acetobacter sp. PA97.