• Applied Chemistry for Engineering
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• v.34 no.3
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• pp.327-329
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• 2023

In this study, an experiment was conducted to investigate the effect of the concentrations of tryptone, an organic nitrogen supplement, and sodium tungstate on the growth of microbial and the production of acetic acid and ethanol in the culture of Clostridium ljungdahlii. Microbial growth increased by 144.6%, and ethanol and acetic acid production improved by 8.6% and 36.7%, respectively, when 2.5 g/L of tryptone was added to the medium of the control experiment (0 g/L tryptone). In the experiment with 1 µM Na₂WO₄·2H₂O, which is 100 times higher than the condition of the medium used in the control experiment (0.01 µM Na₂WO₄·2H₂O), there was no significant difference in microbial growth or total production of C2 metabolites, but ethanol production increased and acetic acid production decreased. As a result, the ethanol/acetic acid production ratio increased significantly from 0.24 in the control experiment to 0.56.

• Journal of Life Science
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• v.32 no.11
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• pp.872-881
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• 2022

In this study, we optimized the composition of the indole-3-acetic acid (IAA) production medium using response surface methodology on Pantoea agglomerans SRCM 119864 isolated from soil. IAA-producing P. aglomerans SRCM 119864 was identified by 16S rRNA gene sequencing. There are 11 intermediate components known to affect IAA production, hence the effect of each component on IAA production was investigated using a Plackett-Burman design (PBD). Based on the PBD, sucrose, tryptone, and sodium chloride were selected as the main factors that enhanced the IAA production at optimal L-tryptophan concentration. The predicted maximum IAA production (64.34 mg/l) was obtained for a concentration of sucrose of 13.38 g/l, of tryptone of 18.34 g/l, of sodium chloride of 9.71 g/l, and of L-tryptophan of 6.25 g/l using a the hybrid design experimental model. In the experiment, the nutrient broth medium supplemented with 0.1% L-tryptophan as the basal medium produced 45.24 mg/l of IAA, whereas the optimized medium produced 65.40 mg/l of IAA, resulting in a 44.56% increase in efficiency. It was confirmed that the IAA production of the designed optimal composition medium was very similar to the predicted IAA production. The statistical significance and suitability of the experimental model were verified through analysis of variance (ANOVA). Therefore, in this study, we determined the optimal growth medium concentration for the maximum production of IAA, which can contribute to sustainable agriculture and increase crop yield.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.695-700
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• 1996

In other to produce vinegar using maesil, acetic acid bacteria were selected from several conventional vinegars, and total 16 acetic acid producing bacterial strains were isolated. Among the isolated strains, a strain was selected from the medium with maesil juice which showed the highest productivity of acetic acid. The strain was identified as Acetobacter sp. VC-2 and it's cultural characteristics were also investigated in the batch shake flasks. The medium containing 2% acetic acid, 6% ethanol, 0.2% glucose, 0.3% yeast extract and 30% maesil juice was suitable for acetic acid production with Acetobacter sp. VC-2 at 3$0^{\circ}C$. The acidity of culture medium was reached to 6.5% after 8 days shaking cultivation at 3$0^{\circ}C$. The main components of organic acids were acetic, citric, malic and tartaric acid, and they were 4.28, 1.38, 0.48 and 0.30%, respectively.

• Natural Product Sciences
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• v.2 no.2
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• pp.115-118
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• 1996

Lipase specific activity in cocoa beans varied from 70 to 40 ${\mu}mol/min/mg$ protein during six days of fermentation. At the end of this period most parts of the cotyledon has turned to brown color which would be more distinguishable after drying. The beans were slightly swollen thus causing its testa to disintegrate. During fermentation there was a decrease in pH from 6.4 to 5.8. Whereas the percentage of acetic acid was increased by 0.04% of wet weight beans on the third day but decreased progressively with time.

• Journal of the Korean Society of Food Culture
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• v.9 no.1
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• pp.79-85
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• 1994

This study was conducted to determine the optimum conditions for the preparation of traditional Korean whole cabbage Kimchi with salted shrimp. Sensory, physical and chemical characteristics of Kimchi with various salted shrimp level(1.8, 3.6%), fermentation time(12, 24, 36 hrs) and storage period(1, 4, 7 days) were measured. As the fermentation time and storage day were extended, pH of Kimchis decreased but titratable acidity of Kimchis increased. The more salted shrimp in Kimchi resulted in the higher titratable acidity. The longer fermentation time and the longer storage resulted in the more citric, malic and succinic acid, and the less lactic and acetic acid in Kimchi. The optimum conditions for the preparation of Korean whole cabbage Kimchi were 3.6% salted shrimp level, 12 hours fermentation time and 84 hours(3.5 days) storage period.

• Journal of the East Asian Society of Dietary Life
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• v.4 no.2
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• pp.39-44
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• 1994

To prepare the basic information for the fermentation of high quality persimmon vinegar in the farm. the quality of the complex fermented persimmon vinegar(CFPV) was compared to that of naturally fermented persimmon vinegar (NFPV). The titratable acidity of the CFPV was 3% which was the half concentration of the NFPV. The content of total free sugar by HPLC was 6% in CFPV and NFPV was 5%. Organic acid compositions in persimmon vinegar were oxalic acid, malic acid, lactic acid, citric acid, succinic acid and glutaric acid in addition to acetic acid. Total content of the organic acids in NFPV was higer than in CFPV. Especially, the content of latic acid in NFPV was very higher than that of CFPV. the flavour, color and taste of persimmon fruit itself in CFPV were stronger than those in NFPV.

• Journal of Life Science
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• v.11 no.3
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• pp.211-217
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• 2001

Optimum processing conditions of vinegar using esa tangle extracts were investigated. Sea tangle vineagr was prepared by adding 3% and 5% of glucose, 6% and 10% of ethanol to sea tangle extracts and inoculating acetic acid bacteria. After fermentation for 30 days at 3$0^{\circ}C$, pH was similar to 3.22, 3.21, 3.25 and 3.28 days it was 4.75%, 4.77%, 5.61% and 5.87% respectively. Contents or reducing sugar was 0.70%, 0.70%, 0.88% and 0.89% in initial time of fermentation but it was rapidly decreased by 10 days of fermentation to 0.20%, 0.19%, 0.22%, and 0.21%, respectively. Ethanol contents was 5.88%, 9.77%, 5.75% and 9.68% in initial time of fermentation but it was rapidly decreased by 15 days of fermentation to 1.05%, 1.62%, 0.45% and 1.23%, respectively and it was addition of 5% glucose and 6% ethanol and fermentation for 20 days at 3$0^{\circ}C$. Quality for sea tangle vinegar manufactured using optimum condition were as follows respectively; pH 3.25, acidity 5.38%, total sugar 1.72%, iodine 1,537.2 ppm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.132-140
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• 2019

Fermented total mixed ration (TMR) is a novel feed for ruminants in South Korea. The purpose of this study was to evaluate the effects of lactic acid bacteria (LAB) on the quality of TMR and in vitro ruminal fermentation. Strains of three LAB spp. (Lactobacillus plantarum, L. brevis, L. mucosae) were used in fermentation of TMR. Inoculations with the three LAB spp. lowered pH and increased concentrations of lactic acid, acetic acid, and total organic acid compared to non-LAB inoculated control (only addition of an equivalent amount of water) (p<0.05). Bacterial composition indicated that aerobic bacteria and LAB were higher. However, E. coli were lower in the fermented TMR than those in the control treatment (p<0.05). Among the treatments, L. brevis treatment had the highest concentration of total organic acid without fungus detection. Gas production, pH, and ammonia-nitrogen during ruminal in vitro incubation did not differ throughout incubation. However, ruminal total VFA concentration was higher (p<0.05) in the LAB spp. treatments than the control treatment at 48 hours. Overall, the use of L. brevis as an inoculant for fermentation of high moisture. TMR could inhibit fungi growth and promote lactic fermentation, and enhance digestion in the rumen.

• Entomological Research
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• v.48 no.6
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• pp.514-521
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• 2018

Drosophila melanogaster Meigen and Drosophila suzukii Matsumura are taxonomically close Drosophila species belonging to the family Drosophilidae and melanogaster group. D. melanogaster is thought to be evolutionarily adapted to overripe, decaying, and fermented fruits, in which large amounts of chemicals such as ethanol, acetic acid, and 2-phenylethanol are produced, whereas, D. suzukii is attracted to fresh ripening fruit. Considering the distinct habitats of the two flies, D. suzukii is hypothesized to exhibit higher susceptibility to these chemicals than D. melanogaster. Therefore, in this study, we investigated the survival rate of the flies at various concentrations of three chemicals (2-phenlyethanol, acetic acid, and ethanol) and calculated the lethal concentration (LC) values to compare the tolerance and susceptibility of D. melanogaster and D. suzukii to the chemicals. Our results revealed that D. melanogaster exhibited higher tolerance than D. suzukii to all chemicals, supporting the hypothesis of different evolutionary adaptations to distinct habitats of the two flies.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.789-795
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• 2014

Acetic acid is the most abundant and serious ethanol fermentation inhibitor in dilute-acid hemicellulosic hydrolysates. A mixture of xylose, acetic acid and sulfuric acid was chosen as a simulated hemicellulosic hydrolysate so as to find an optimal separation system to selectively remove acetic acid from the hydrolysates. In order to attain the purpose, emulsion liquid membrane was applied to removal of acetic acid from the simulated hemicellulosic hydrolysate. The effects of main constituents of water-in-oil (W/O) emulsion, such as amine extractant type, surfactant composition, additive type, and type and concentration of stripping agent, on extraction of acetic acid, xylose, and sulfuric acid in the simulated hemicellulosic hydrolysate were investigated. Under specific experimental conditions, degree of extraction of acetic acid was higher than 95% while loss of xylose was insignificant, which means that the current emulsion liquid membrane can be an economically feasible process.