• Journal of Life Science
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• v.32 no.2
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• pp.119-124
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• 2022

To effectively isolate acetic acid bacteria for producing makgeolli vinegar, various products were researched, and Acetobacter pasteurianus CK-1, a strain that is excellent in acetic acid production, was finally isolated. The optimal growth temperature of the isolated strain was confirmed to be 30℃, and it grew well in the pH range of 5.5~6.5, with optimal growth at pH 6. A. pasteurianus CK-1 had the most active proliferation when the initial ethanol concentration in the medium was 4%, and growth was possible even at an ethanol concentration of 7%. When inoculating the isolated strain into makgeolli to induce acetic acid fermentation, the pH at the beginning of fermentation was 3.54, which was gradually lowered to 2.77 after 18 days of fermentation. The acidity was 0.75% at the beginning of fermentation and gradually started to increase from the 4th day of fermentation. The final acidity at the end of fermentation was 5.54%. In the vinegar fermented by inoculating A. pasteurianus CK-1, acetic acid content was detected to be as high as 3,575.7±48.6 mg%, and the malic acid and citric acid contents were 2,150.8±27.6 and 55.8±3.7 mg%, respectively. Further, it was confirmed that the content and ratio of the organic acids produced significantly differed depending on the type of inoculated bacterial strain. During acetic acid fermentation, the populations of yeast and A. pasteurianus CK-1 were inversely changed. In the initial stage of fermentation, yeast dominated, and after 10 days of fermentation, A. pasteurianus CK-1 slowly proliferated and reached stationary phase.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.252-256
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• 2013

We tested the possibility of utilizing Korea domestic wheat (winter wheat variety "keumkangmil") as a source of vinegar production. After saccharification of the whole-wheat flour with wheat malt, the saccharized liquid undergoes alcoholic fermentation, followed by acetic fermentation. Acetic acid bacterium A8, which showed the highest acetic acid production (4.56%) with domestic wheat as substrate, was selected from conventional vinegars. The strain A8 was identified as Acetobacter pasteurianus A8 through phylogenetic study using 16S rDNA sequencing analysis. The optimal condition for the malt enzyme was found to be $15^{\circ}C$ for germination periods of 6 days; its amylase activity was 608.4 U. Acetic acid production from domestic wheat substrate supplemented with 5% ethyl alcohol reached 5.8% after 24 days of static fermentation at $30^{\circ}C$ with a seeding rate of 5%.

• Food Science and Preservation
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• v.30 no.1
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• pp.65-77
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• 2023

In this study, we investigated the immunological properties of six strains of Acetobacter pasteurianus through nuclear factor-kappa B/activator protein-1 (NF-κB/AP-1) transcription factor activation and nitric oxide (NO) and cytokine production in macrophages. We found that the six A. pasteurianus strains had no significant inhibitory effect on the cell viability of RAW-Blue^TM cells at the concentration of (25, 50, 100 CFU/macrophage). The production of NO and cytokines (TNF-α, IL-1β, and IL-6) showed different abilities of immune activation for each strain, and it was 0.7 to 0.9 times higher than that of the LPS (100 ng/mL, v/v) positive control and 7 to 8 times superior to that of the negative control group. To explore the underlying mechanism, we evaluated the mRNA expression of pro-inflammatory genes. Consequently, we found that inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 expression including genes expression of cytokines were elevated by the six A. pasteurianus treatment. These results suggested that the six strains of A. pasteurianus have an excellent industrial application value as a functional material for the purpose of enhancing immune function.

• The Korean Journal of Food And Nutrition
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• v.33 no.6
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• pp.737-746
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• 2020

In this study, we developed vinegar depending on the quantity consumed and type of peeled and unpeeled roots of Platycodon grandiflorum (PG) using Acetobacter pasteurianus A11-2, analyzed vinegar samples using colorimeter and HPLC for 15 days to assess the characteristics on quality, and evaluated their antioxidant activity using 1,1-diphenyl-2-picry1 hydrazy1 (DPPH) and 2.2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities. The major result in PG vinegar was the high acidity of 6.39~6.74% and alcohol was totally converted on the 15th day of fermentation. When we fermented vinegar from peeled roots of 8% PG with a starter culture, we observed high contents of acetic acid, platycodin D, and total polyphenol and high antioxidant activity. Moreover, the vinegar fermented using 8% peeled roots of PG had the high intensity on umami and sour taste and low salty, bitter, and astringent tastes. Consequently, we could develop the PG vinegar with quality and functional characteristics from 8% peeled roots and A. pasteurianus A11-2.

• Mycobiology
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• v.47 no.2
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• pp.250-255
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• 2019

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ${\sim}1{\times}2{\mu}m$ in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1216-1224
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• 2017

Acetic acid bacteria strains were isolated from commercial natural vinegar. Ten isolated strains were identified using 16S rRNA gene sequencing data after evaluating the ethanol- and sulfur-tolerance. Eight of the strains isolated were identified as Acetobacter pasteurianus. A. pasteurianus JAC002, JAC005, and JAC008 strains, which showed a high ethanol tolerance, were selected for making "Makgeolli seed-vinegar". Rice wine vinegars were manufactured with the selected strains through fermentation, and their physicochemical properties and antimicrobial activities were evaluated. A. pasteurianus JAC002 strain showed the highest oxidation ability to acetic acid from ethanol on the twentieth day of fermentation, resulting in 4.21% total acidity, 3,791.77 mg% acetic acid content, and 2,931.78 mg% ethanol consumption content. Rice wine vinegar manufactured with the A. pasteurianus JAC002 strain showed increased antimicrobial activities against Staphylococcus aureus (KACC1927) and Escherichia coli (KACC10115). As a result, A. pasteurianus JAC002 strain was found to be the most suitable strain for "Makgeolli seed-vinegar".

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.761-767
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• 2021

Strawberries fermented with Acetobacter pasteurianus SRCM60009 were prepared, and the quality characteristics and physiological activity were measured. As the fermentation period increased, viable cell counts increased, pH decreased, and total acidity increased from 1.09% to 4.20%. The organic acid content of strawberry through acetic acid fermentation was confirmed in the following order: acetic acid, succinic acid, citric acid, and lactic acid. Measurement of α-glucosidase and pancreatic lipase inhibitory activities and angiotensin converting enzyme inhibitory activity showed significantly increased physiological activity owing to fermentation. The use of strawberry vinegar as a functional material was confirmed by measuring the anti-diabetic, anti-obesity, and anti-hypertensive physiological activities through acetic acid fermentation of strawberry. Thus, fermented strawberry vinegar can be used as a functional material in vinegar and other foods.

• KSBB Journal
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• v.8 no.4
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• pp.397-404
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• 1993

Two strains were isolated from the vinegar of Korean traditional fermented rice wine and the vine gar of fermented persimmon, respectively. These strains, designated as KM and BPV, were identified as the genus Acetobacter with respect to morphological, physiological, and biochemical characteristics. The Isolates oxidized ethanol to acetate and over-oxidized acetate or lactate to CO2 and H2O. They were positive in catalase test, while being negative in oxidase, gelatin liquefaction, VP test, H2O production and indole formation tests. No ${\gamma}$-pyrones ware produced from glucose and fructose. KM was tolerant of 11% ethanol while BPV was relatively sensitive to ethanol at a higher concentration than 5%. The guanine-plus-cytosine contents of the DNA of KM and BPV strains were 53.8 and 56.6 mol%, respectively. The cellular fatty acid compositions contained in these isolates were saturated straightchain C14:0 and C16:0,, and unsaturated straight-chain C18:1. Major ubiquinone system of KM was Q-9, but that of BPV was Q-10. In morphophysiological and biochemical aspects, KM strain was similar to Acetobacter pasteurianus. However, BPV strain was different from other Acetobacter type strains.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.405-409
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• 1991

The polysaccharide was predominantly composed of glucose (79.60%), galactose (9.68%), mannose(8.67%), fructose (1.96%;) and xylose (0.09%). Major amino acid in protein was consisted of cystein, aspartic acid, valine and glutamic acid. The tumor growth inhibition ratio of the polysaccharide against Sarcoma 180 was at highest level of 64.96%, when administerd at the concentration of 50 mg/kg and life prologation ratio showed 28.91% at the concentration of 50 mg/kg. The direct cytotoxic effect of polysaccharide was not observed in the tumor bearing mice with Sarcoma 180 in vitro.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.403-415
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• 2018

The aims of this novel work were to determine the microbial strains and exopolysaccharide (EPS) producers in water kefir from Nakhon Ratchasima Province, Thailand. Thirty-three microbial strains were identified using 16S rRNA gene analysis consisting of 18 bacterial strains, as 9 strains of acetic acid bacteria (AAB), 9 strains of lactic acid bacteria (LAB), and 15 yeast strains. All bacteria were able to produce EPS with a diverse appearance on agar media containing different sugars at a concentration of 8%. Culture supernatants from AAB and LAB showed 31-64% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity with the highest antioxidant activity of 64% from Acetobacter pasteurianus WS3 and WS6. Crude EPS from A. pasteurianus WS3 displayed the highest ferric reducing antioxidant power at 280 mM $FeSO_4/g$ EPS, greatest anti-tyrosinase activity at 20.35%, and highest EPS production of 1,505 mg EPS/L from 8% sucrose. These microbes offer beneficial health implications and their EPSs can be used as food additives and cosmetic ingredients.