• Mycobiology
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• v.35 no.4
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• pp.210-214
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• 2007

Antibacterial and antifungal activities of liquid culture filtrate, water and ethanol extract (solid culture) of Stereum ostrea were evaluated against 5 bacteria and 3 plant pathogenic fungi. To determine the minimal inhibitory concentration (MIC), we studied $5{\sim}300\;mg/ml$ concentrations against bacteria and fungi separately. The MIC was 10 mg/ml for Bacillus subtilis and 40 mg/ml for Colletotrichum gloeosporioides and Colletotrichum miyabeanus. Liquid culture filtrate was more effective against Gram positive than Gram negative bacteria, and Staphylococcus aureus was the most inhibited (20.3 mm) bacterium. Water and ethanol extracts were effective against both Gram positive and Gram negative bacteria, and water extract was better than ethanol extract. In water and ethanol extract, inhibition zones were 23.6 and 21.0 mm (S. aureus) and 26.3 and 22.3 mm (Pseudomonas aeruginosa), respectively. For plant pathogenic fungi, the highest and lowest percent inhibition of mycelial growth (PIMG) was found 82.8 and 14.4 against C. miyabeanus and Botrytis cinerea in liquid culture filtrate, respectively. In water extract, the PIMG was found to be the highest 85.2 and lowest 41.7 for C. miyabeanus and C. gloeosporioides, respectively. The inhibitory effect of ethanol extract was better against C. miyabeanus than C. gloeosporioides and B. cinerea. Among 3 samples, water extract was the best against tested pathogenic fungi. This study offers that the extracts isolated from S. ostrea contain potential compounds which inhibit the growth of both bacteria and fungi.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.409-417
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• 2012

We identified two novel expansin (EXP) genes in the expressed sequence tag database of Bursaphelenchus xylophilus, designated as Bx-EXPB2 and -EXPB3. Novel Bx-EXPBs encoded 150 amino acids and their similarities in coding sequence were 70.7-84.0% to the previously reported EXPB1 of B. xylophilus. Bx-EXPB2 and Bx-EXPB3 were clustered with Bx-EXPB1 and Bm-EXPB1, respectively, forming the independent phylogeny with other nematode EXPs. All identified Bx-EXPBs contained the signal peptide and were only expressed during the propagative stage, suggesting that they are secreted to facilitate nematode migration through hosts by loosening cell walls during infection. Quantitative real-time PCR analysis showed that the relative accumulation of Bx-EXPB3 mRNAs was the highest among the three Bx-EXPs examined and the order of mRNA accumulation was as follows: Bx-EXPB3 > Bx-EXPB2 >> Bx-EXPB1. Homology modeling of Bx-EXPBs showed that the structurally optimum template was EXLX1 protein of Bacillus subtilis, whichshared residues essential for catalytic activity with Bx-EXPB1 and Bx-EXPB2 except for Bx-EXPB3. Taken together, Bx-EXPB1 and Bx-EXPB2 may be involved migration through plant tissues and play a role in pathogenesis.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.307-311
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• 1991

A moderate halophile, ES 10 which produces a high level of alkaline protease was isolated from the salted anchovies and indentified as a strain of Halomonas sp. The optimum growth of the Halomonas sp. was revealed in the presence of 2 M NaCl and its growth rate in the Temporary Synthetic Medium was increased by adding DL-alanine, but inhibited by adding L-proline. The concentration of $Na^+$, $K^+$ and $Mg^{2+}$ in the cell mass of the Halomonas sp. ES 10 was 5-, 25- and 35-fold higher by dry weight basis, respectively than those of B. subtilis or E. coli. Norberg and Hofsten medium with 1 M NaCl was selected as the best medium for producing high level of alkaline protease. The optimum temperature for the growth and protease production was equally $20^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.446-452
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• 2011

Total 480 lactic acid-producing bacteria were isolated from five kinds of kimchi, and their antibacterial activity was tested against Salmonella enterica serovar Typhimurium, Bacillus subtilis, and Pseudomonas aeruginosa using an agar diffusion assay. Among them, 340 isolates showed a halo on MRS agar against one or more indicator strains, which were identified using multiplex PCR, an API 50CHL kit, and a 16S rDNA sequence analysis. As a result, 169 Lactobacillus plantarum, 20 Lactobacillus fermentum, two Lactobacillus paracasei ssp. paracasei, two Lactobacillus sp., and 15 Pediococcus sp. were identified. This may be the first report on the isolation of antibacterial Lactobacillus fermentum from kimchi.

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.51-54
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• 2000

In the 5'-flanking region of the D-AAT, AspAT and AlaDH gene, I found three or two pairs of sequences(designated as Pl, P2, P3) which show significant similarity to the E.coli consensus sequences of -35 and -10 for promoters. The spacing between -35 and -10 is 16 to 18bp in all the three putative promoters Pl, P2 and P3 which is in good agreement with the preferred spacer length in E.coli and in B.subtilis. Therefore, the putative promoters may also function to increase the efficiency of transcriptional initiation. The most stable, double-helical“Shine-Dalgarno”pairing is formed with a free energy change(ΔG) of -13.0 kcal/mol, -9.6 kcal/mol, -15.8 kcal/mol.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.1035-1038
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• 1995

Antimicrobial activity of bamboo leaves extract on microorganisms related to kimchi fermentation was investigated. Bamboo leaves were extracted with several ogranic solvents such as methanol, acetone, ethyl ether, and ethyl acetate. The bamboo extract with ethyl acetate showed the strongest antimicrobial activity among them. Strong antimicrobial activities of the extract against microorganisms related to kimchi fermentation and food spoilage indicated that the extract had a wide range of antimicrobial spectrum. The antimicrobial activity was especially strong against Brettanomyces custersii, Klebsiella oxytoca, Pichia membranaefaciens which cause kimchi softening. In addition, the antimicrobial activity of bamboo leaves extract was higher than that of 0.5% and 1.0% sorbic acid, and moreover it was stronger in pH 5 compared to pH 7.

• Food Science and Preservation
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• v.7 no.3
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• pp.326-330
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• 2000

Antimicrobial activities of marinex and preservative characteristics of soybean curds soaked in diluted marinex were investigated. One hundred ml of marinex showed antimicrobial activities against Streptococcus mutans, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli and Escherichia coli O-157 on a paper disc test. The growth of the microorganisms were inhibited with 200${\mu}{\ell}/m{\ell}$ of culture media. pH of soybean curd treated with marinex decreased to 1 day and then slowly increased as storage time increase, which was higher than control after 1 day of storage and lower after that time. Little difference was observed between control and marinex treated soybean curd in color. Hardness and chewiness of the treated sample were higher than those of the control. The numbers of E. coli and bacteria of the treated sample were lower than those of control during storage. The inhibition of the growth of E. coli and bacteria was dose dependent.

• Journal of Haehwa Medicine
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• v.20 no.2
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• pp.67-78
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• 2012

Volatile odor substance originating from drying and making dry peel of tangerine from the fruit skin were collected through modern equipment. The anti-microbial activity of the substance against various skin-residing bacteria including acne, dandruff, athelete's foot, and gingivitis inducing microorganisms were tested. Anti-microbial activity was observed in purified oil, where 87 to 92% was D-limonene. Against P. acnes, 103$cfu/m{\ell}$ of P. acnes were suppressed at 0.1% Unshiu oil, and the MIC was measured to be 0.3%. Against P. ovale, a dandruff inducing bacteria, 104$cfu/m{\ell}$were suppressed at 0.1% Unshiu oil, and the MIC was measured to be 0.1%. Against T. rubrum and T. Mentagrophytes, both of which are athelete's foot inducing microorganisms, 83% of T. Mentagrophytes and 99.9% of T. rubrum were suppressed at 0.1% Unshiu oil, and the MIC were 0.3% and 0.05% respectively. Against S. aureus, a skin infection inducing bacteria, 103$cfu/m{\ell}$ of the bacteria were suppressed at 0.1% Unshiu Oil. Against B. subtilis, a non-pathogenic sporulating bacteria, 104$cfu/m{\ell}$ of the bacteria were suppressed at 0.1% Unshiu Oil. Against C. albicans, found in mucous membranes, 104$cfu/m{\ell}$ of the bacteria were suppressed at 0.1% Unshiu Oil. Against Aspergillus niger, an otomycosis inducing microorganism, 99.9% were suppressed at 0.1% Unshiu Oil. The results above indicate that low concentration of purified oil extracted from tangerine had strong antimicrobial activities against bacteria and fungi residing on the skin, and that it may be developed into skin disorder treating products in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.822-829
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• 1999

Antimicrobial activity of dandelion(Taraxacum platycarpum D.) was investigated. Methanol extract of dried dandelion was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as B. subtilis, L. monocytogenes, S. aureus, E. coli and V. parahaemolyticus at $500\mu\textrm{g}/disc$. Ethylacetate fraction was further fractionated into 13 fractions by silica gel column and thin layer chromatography(TLC). The results showed that ethylacetate fractions No. 4, 5 and 6 had high antimicrobial activity. These were mixed again, re separated and five fractions were obtained. Among them, No. 2 fraction had the highest inhibitory effect on the microorganisms, which was then separated into six fractions. In the 3rd fractionation, No. 3 fraction was identified as benzoic acid by HPLC, $^{1}H-NMR$ and GC MS.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.212-217
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• 2000

This study was determined protein reaction, antioxidative activity, nitrite scavening ability and antimicrobial activity of tannins isolated from astringent persimmon fruits. Tannins extracted from green persimmon fruits reacted highly with BSA(bovine serum albumin). Reactions between tannins and BSA were more active when contents of tannin were higher than that of BSA. Antioxidative abilities of green persimmon tannin were comparable to that of BHT(butylated hydroxytoluene). Green persimmon tannins exhibited remarkable nitrite-scavenging activity. Different antimicrobial activities of persimmon tannins were observed depending on the maturity. The growth of V. parahaemolyticus and E coil were highly inhibited by the addition of persimmon tannins. Tannins from soft persimmon did not have antimicrobial activities against B. subtilis and S. typhimurium.