• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2693-2697
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• 2014

Background: Isoflavones, which are included in soybeans, have been suggested to protect against prostate cancer. Equol, one of isoflavones, is an intestinally derived bacterial metabolite of daidzein. A newly identified equol-producing bacterium, Slackia sp. strain NATTS, with a high equol-producing activity was isolated from human feces in Japanese adults. Counts of Slackia sp. strain NATTS in intestinal flora have not been assessed with regard to prostate cancer risk. In this study, we investigated the association of serum isoflavones and counts of Slackia sp. strain NATTS with prostate cancer risk in a case-control study. Materials and Methods: Concentrations of isoflavones and counts of Slackia sp. strain NATTS in feces were measured from 44 patients with prostate cancer and 28 hospital controls. The risk of prostate cancer was evaluated in terms of odds ratios (ORs) and 95% confidence intervals (CIs) by the logistic regression analysis. Results: The detection proportions of Slackia sp. strain NATTS in cases and controls were 34.1% and 25.0%, respectively. Counts of Slackia sp. strain NATTS were significantly correlated with serum concentrations of equol both in cases and controls (Spearman correlation coefficients, $r_s$=0.639 and $r_s$=0.572, p<0.01, respectively). Serum concentrations of genistein, daidzein, glycitein, and equol were not significantly associated with risk of prostate cancer. Conclusions: This study found that counts of Slackia sp. strain NATTS correlated with serum concentrations of equol both in prostate cancer cases and controls, but serum isoflavone concentrations were not associated with risk of prostate cancer in our patients.

• Journal of Life Science
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• v.25 no.11
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• pp.1273-1279
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• 2015

Agarase from a novel agar-degrading bacterium isolated from seawater in Namhae at Gyeongsangnamdo province of Korea was characterized. The SH-1 strain was selected from thousands of colonies on Marine agar 2216 media. Almost full 16S rRNA gene sequence of the agarolytic SH-1 strain showed 99% similarity with that of bacteria of Simiduia genus and named as Simiduia sp. SH-1. Agarase production was growth related, and activity was declined from stationary phase. Secreted agarase was prepared from culture media and characterized. It showed maximum activity of 698.6 units/L at pH 7.0 and 30℃ in 20 mM Tris-HCl buffer. Agarase activity decreased as the temperature increased from an optimum of 30℃, with 90% and 75% activity at 40℃ and 50℃, respectively. Agarase was not heat resistant. Slightly lower agarase activity was observed at pH 6.0 than at pH 7.0, without statistical difference, and 80% and 75% activity were observed at pH 5.0 and 8.0, respectively. Neoagarotetraose and neoagarobiose were the main final products of agarose, indicating that it is β-agarase. Simiduia sp. SH-1 and its β-agarase would be useful for the industrial production of neoagarotetraose and neoagarobiose, which have a whitening effect on skin, delaying starch degradation, and inhibiting bacterial growth.

• Journal of Life Science
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• v.19 no.6
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• pp.744-750
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• 2009

A bacterial strain producing highly viscous extracellular polysaccharide was isolated from soil. Through morphological, physiological and chemotaxonomical studies, it was identified as a Bacillus sp. and named Bacillus sp. PS-12. The extracellular polysaccharide, named PS-12 was purified by ethanol precipitation, cetylpyridinium chloride (CPC) precipitation and gel permeation chromatography. The purified polysaccharide was found to consist of glucose, mannose, galactose, and fucose, with a molar ratio of approximately 7:3.2:2:1, respectively. PS-12 was investigated for its immunostimulating activity on murine macrophage RAW264.7 cells using an ELISA assay. PS-12 stimulated the production of TNF-${\alpha}$ to a level 50 times greater than the control and also induced 1L-6 secretion in a dose-dependent manner. The cytotoxicity on RAW264.7 cells by PS-12 was relatively low with 10% cytotoxicity at 2 ${\mu}g$/ml. These results indicate that PS-12 is less cytotoxic to immune cells and possess immunomodulating activity in which it can produce cytokines including TNF-${\alpha}$ and 1L-6 from macrophages.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.165-170
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• 2003

The antioxidative activity of antioxidative substances produced from several bacterial strains isolated from fermented foods were tested by $DPPH\;({\alpha},{\alpha}'-diphenyl-{\beta}-picrylhydrazyl)$ free radical scavenging activity. One of the strains showing the highest antioxidative activity was identified as Bacillus sp. based on the morphological, biochemical, physiological characteristics, and 16S rRNA sequence, and named FF-7. The most optimal medium condition for the production of antioxidative substance from Bacillus sp. FF-7 was 2% galactose as carbon source and l% tryptone as nitrogen source. The antioxidative substance produced from FF-7 in these cultural medium was also tested by in vitro experimental models, the peruxidation of linoleic acid and the peroxidation of rat tissues microsomes by using thiobarbituric acid (TBA) for assay of free malondialdehyde production. The antioxidative activity against lipid peroxidation of rat tissues microsomes was shown in the following order; brain 97.50% > heart 79.95% > kidney 77.84% > spleen 77.47% > testis 69.96% > liver 62.45%. The antioxidative substance produced from FF-7 on linoleic acid peroxidation by IBA method was effectively inhibited during four days, and 0.05% BHT (butylated hydroxytoluene) used comparative control was also effectively inhibited. Results showed that the highest antioxidative activity by DPPH method of antioxidative substance produced from Bacillus sp. FF-7 was obtained by supplementing 2% galactose as carton source and l% tryptone as nitrogen source in cultured medium, this substance effectively inhibited the formation of TBARS in brain microsome in vit개 system and in linoleic acid peroxidation.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.195-199
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• 1998

AH alkalophilic Bacillus SP. AIk-7, isolated from soil, produced ethylene. The characteristics of this microorganism is the ability to grow well under the alkaline condition, at pH 10.3. This strain is similar to Bacillus alkalophilus in terms of morphological, physiological and biological characteristics. In observation of relationship of cell growth and ethylene production according to incubation times, the ethylene synthesis mostly occur from the late exponential phase to the death phase of growth. The purpose of this paper is to study the effects of various substrates on the biosynthesis of ethylene in the intact cell and the cell-free system by the Bacillus sp. AIk-7. In both intact cell and cell-free extract, optimum conditions for ethylene production was achieved at pH 10.3 and 3$0^{\circ}C$. Ethylene was effectively produced from L-Met and 1-aminocyclopropane-1-carboxylic acid (ACC). In this case, ACC as the substrate on ethylene production were two fold higher than L-met at each concentration of substrates. On the other hand, the cell-free ethylene-forming system was used as a tool for the elucidation of the biochemical reaction involved in the formation of ethylene by Bacillus sp. AIk-7. Ethylene production in the cell-free system required the presence of manganese and cobalt ion to be stimulated a little. The result obtained in this work suggests that L-met and ACC may be a precursor more directly related to bacterial ethylene production than any other substrates tested.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.250-257
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• 2014

To develop vinegar with immature Citrus unshiu (IC), bacterial strains with high acetic acid-producing capabilities were isolated and identified, after which their quality characteristics, total phenolic and total flavonoid contents, and antioxidant activities were measured. Five bacterial strains were isolated from naturally fermented C. unshiu, and three were identified as Acetobacter fabarum (A. sp. RIC I) and A. pomorum (A. sp. RIC II, V). A. sp. RIC V showed the highest acetic acid-producing capability and was thus chosen as the candidate strain for further acetic fermentation using IC juice. Vinegars made with 30, 35, and 40% IC juices showed acidities of 5.38, 5.38, and 5.32% and fermentation efficiencies of 73, 72, and 70%, respectively. The fermentation periods required to reach greater than 5% acidity were 11, 9, and 9 days for vinegars containing 30, 35, and 40% IC juices, respectively. Fructose and glucose contents of the vinegars increased along with total organic acid contents including acetic acid, with increasing IC juice contents. Total phenolics were 1,546.6 and $230.9{\mu}g$ GAE/mL, whereas total flavonoids were 1,004.7 and $175.1{\mu}g$ QE/mL in vinegars made with IC and mature C. unshiu (MC) juices, respectively. DPPH free radical scavenging activities were 29% and 5%, ABTS radical scavenging activities were 62.0% and 17.9%, SOA scavenging activities were 60.9% and 41.7%, and XO scavenging activities were 32.5% and 5% in vinegars made with IC and MC juices, respectively. Therefore, vinegars made with 35% and 40% IC juices using A. sp. RIC V as the acetic acid fermentation strain showed potent antioxidant activities with greater total phenolic and flavonoid contents, promoting their use as functional vinegars.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.205-212
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• 2011

The potential factors for quality loss of cleaned fresh ginseng and technology to be associated with the improvement of marketability through pre-packaging fumigation were examined. Major microorganisms isolated from fresh ginseng included Botrytis cinerea, and Erwinia sp. Others such as Cylindrocarpon sp., Fusarium spp., Pennicilium spp., Bacillus spp. were also found at relatively low frequency. The bacterial density of vacuum packaged fresh ginseng rapidly increased during simulated marketing. Little correlation between bacterial growth and package swelling was found. In order to improve packaging method of fresh ginseng, pre-packaging treatment of 2-phenylethyl alcohol (PE, 100 uL/L, 4 hr) was examined. The fumigation treatment effectively inhibited the growth of bacteria density and also effective on keeping firmness of ginseng root, especially in cortical portion. The internal gas compositions of plastic container packaged for ginseng were approximately ranged between 6 to 8% $O_2$and 3 to 4% $CO_2$. The $O_2$ level of fumigation treatment was lower than control whereas $CO_2$ level was higher. The upsurge of ethylene evolution I day after simulated marketing was found only in fumigation treatment but it returned to ordinary level at day 2. The sucrose content of 2-PE treatment was significantly reduced at 5 days after simulated marketing but reducing sugars like glucose and fructose remained at higher level. The difference in sugar levels was reduced after 10 days of simulated marketing. The decay of fresh ginseng began at the lateral or fine root, which is weak to physical damage, in general. The epidermis was more damaged. Plastic container packaging with PE fumigation could be an alternative to vacuum packaging, which allows an aerobic environment and prevents anaerobic respiration. Further study of pre-package fumigation is required to improve technology of fresh ginseng marketing.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.106-107
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• 2003

The effect of biological control agent Bacillus sp. (BAC03-3-1, BAC03-3-2, BAC02-4) on pre- and postemergence Sclerotinia rot of perilla (Perilla frutescens var. japonica) caused by Sclerotinia sclerotiorum was determined from greenhouse field trials. The ability of this antagonist to reduce germination of sclerotia of S. sclerotiorum was also evaluated. In the greenhouse, suspension of BAC03-3-1 application as root drench of perilla, which provided as little as 10$\^$7/ cells/ $m\ell$ per gram of soil, significantly increased plant stand in pathogen-infested soil over that in the untreated control. All three isolates reduced the germination of sclerotia of S. sclerotiorum in loamy sand soils in the greenhouse. In loamy sand amended with rice bran the sclerotial germination was inversely correlated (r = -0.79) with perilla stand in the greenhouse. However, a higher rate of bacterial suspension with rice bran(Ig dwt./100g soil) than that applied with bacterial suspensions only was necessary to achieve a comparable reduction in sclerotial germination. In field study, all three isolates added to soil to provide 10$\^$7/ cells/$m\ell$ per gram significantly prevented Sclerotinia rot (73-85％) after 35 days of growth. The isolate BAC02-4, BAC03-3-1 and BAC03-3-2 gave final stands of 65 to 75, 60 to 70, and 55 to 60％, respectively. The addition of rice bran(1 ％) to loamy sand in the field resulted in a 10-fold increase in propagule numbers of the three isolates within 10 days of application.

• Journal of Environmental Science International
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• v.29 no.8
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• pp.819-826
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• 2020

Production of Bacterial Cellulose (BC) by Gluconacetobacter sp. A5 was studied in shaken culture using different cost-effective carbon sources and its structural and mechanical properties were evaluated. Glycerol showed the highest level (7.26 g/l) of BC production, which was about three times higher than the yield in glucose medium. BC production depended not only on the decrease in pH, but also on the ability of Gluconacetobacter sp. A5 to synthesize glucose from different carbon sources and then polymerize it into BC. All BC produced from different carbon sources exhibited a three-dimensional reticulated structure consisting of ultrafine cellulose fibriles. Carbon sources did not significantly change the microfibrile structure of the resulting BC. BC produced from glucose medium had the lowest water-holding capacity, while BC from molasses medium had the highest. XRD data revealed that all BC were cellulose type I, the same as typical native cellulose. The crystalline strength of BC produced in glucose medium was the highest, and that in molasses medium was the lowest. Our results suggest that glycerol could be a potential low-cost substrate for BC production, leading to the reduction in the production cost, and also to produce BC with different mechanical properties by selecting appropriate carbon source.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.2
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• pp.169-173
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• 2010

This study evaluated the effects of gamma ray irradiation on the safety of dried seafood products. Dried salted squid, Engraulis japonica, Hizikia fusiformis, Mytilus coruscus, and Porphyra tenera were gamma-irradiated at doses of 0, 1, 3, and 5 kGy. The total bacterial populations were then enumerated on total plate count agar, and bacteria isolated from the samples were identified by 16S rDNA sequencing. In addition, the isolated strains were inoculated in the products to determine $D_{10}$ values. The total bacterial populations in the dried seafood products ranged from 3.40 to 6.59 log CFU/g, and those of yeasts and molds ranged from 2.21 to 4.56 log CFU/g. The sequence analysis identified Staphylococcus sp. as the most common species in the dried seafood products, except for dried P. tenera. The $D_{10}$ values of the contaminating bacteria were lower than 0.7 kGy, except for Deinococcus sp., which had a value of 1.39 kGy. This study demonstrated that gamma irradiation could be used to improve the safety of dried seafood products.