• Applied Biological Chemistry
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• v.41 no.1
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• pp.104-109
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• 1998

Methanol extracts from 84 Indian plant samples (50 species in 31 families) and 27 African plant samples (20 species in 12 families) in vitro were tested for their growth-inhibitory activities against Bifidobacterium bifidum, Bifidobacterium longum, Lactobacillus acidophilus, Clostridium perfringens, and Escherichia coli, using a paper disc agar diffusion method under $O_2-free$ conditions. The responses varied with bacterial strain, plant species and plant part. Extracts from Cymbopogon citratus whole plants, Ocimum basilicum whole plant, Madhuca indica flowers, and Aegle marmelos leaves among Indian plant samples moderately or strongly inhibited the growth of Cl, perfringens whereas moderate growth-inhibitory activity against E. coli was obtained from extract of Indian O. basilicum whole plants. These plant extracts did not affect the growth of the lactic acid forming bacteria tested. These results may be an indication of at least one of the pharmacological actions of these tropical plants.

• Toxicological Research
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• v.18 no.3
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• pp.249-257
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• 2002

Cytochrome P450 3As such as 3A4 and 3A5 metabolize a wide range of pharmaceutical compounds. The vectors for the expression of fusion protein containing an N-terminal human P450 3A4 or P450 3A5 sequences and a C-terminal rat NADPH-cytochrome P450 reductase moiety were constructed. These plasmids were used to express the fusion protein in Escherichia coli DH5$\alpha$ cells. High levels of expression were achieved (100~200 nmol/liter) and the expressed fusion protein in E. coli membranes were catalytically active for nifedipine oxidation, a typical enzymatic activity of P450 3A4. The NADPH-P450 reductase activities of these fusion protein were also determined by measuring reduction of cytochrome c. To fine a specific Inhibitor of P450 3A4 from naturally occurring chemicals, a series of isothiocyanate compounds were evaluated for the inhibitory activity of P450 using the fusion proteins in E. coli membranes. Of the five isothiocyanates (phenethyl isothiocyanate, phenyl isothiocyanate, benzol isothiocyanate, benzoyl isothiocyanate and cyclohexyl isothiocyanate) tested, benzoyl isothiocyanate showed a strong inhibition of P450 3A4 with an $IC_{50}$value of 2.8 $\mu\textrm{M}$. Our results indicate that the self-sufficient fusion protein will be very useful tool to study the drug metabolism and benzyl isothiocyanate may be valuable for characterizing the enzymatic properties of P450 3A4.

• Food Engineering Progress
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• v.13 no.4
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• pp.352-359
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• 2009

Lactic acid bacteria was isolated for the production of probiotic animal feed supplemented with garlic and its antimicrobial properties were investigated. A total of 112 strains of lactic acid bacteria which grew on the medium containing garlic extract were isolated from kimchi, jeotgal, and jangachi. Among them 14 strains were tested for acidand bile salt-resistance as well as antimicrobial activities against animal pathogenic bacteria such as Salmonella choleraesuis, Escherichia coli, Staphylococcus aureus, and Shigella flexneri. Of these strains, a strain P'GW50-2 from pickled scallion with most desirable properties was selected and identified as Lactobacillus plantarum TJ-LP-002. Antimicrobial activity of L. plantarum TJ-LP-002 showed relatively wide range of inhibition spectrum against Gram negative bacteria such as Aeromicrobium hydrophila, E. coli, Pseudomonas, Salmonella, Shigella, and some Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus, Clostridium perfringens, and Propionibacterium.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1014-1019
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• 1994

To develope natural food preservatives, ethanol extract was preapred from the leaf mustard (Brassica juncea Coss) and antimicrobial activities were examined against 12 microorganisms which were food borne pathogens and/or food poisioning microorgaism and food-related bacteria and yeasts. The most active animicrobial concentration of the ethanol extract for most Gram positive microorganisms, Gram negative microorganisms, and lactic bacteria and yeasts was found to be 10, 20 and 40 mg/ml, respectively. when tested by a dose-response manner. Growth of Escherichia coli and STaphylococcus aureus were completely inhibited 4 hours after the addition of more than 20mg/ml of ethanole ethanol extract to the logarithic phase. Scanning electron icrographs of E. coli and Staph, aureus treated with ethanol extrract exhibited morphological changes, including the irregularly contracted cell surface of E. coli and expanded ellipsoidal shape of the Staph. aureus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1548-1553
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• 2008

This study was concerning various physiological activities of agar hydrolysates. All agar hydrolysates showed strong antimicrobial activity against Bacillus subtilis and Bacillus cereus. Also, the agar hydrolysates prepared at the temperature of $110^{\circ}C$ or $120^{\circ}C$ showed antimicrobial activity against St. aureus and E. coli. Among the agar hydrolysates, several hydrolysates treated with citrate or malate at $110^{\circ}C$ or $120^{\circ}C$ conditions showed tyrosinase activity inhibition, and their inhibition rates of tyrosinase activity were about 80%. Some tested samples treated with 0.5% organic acid at $100^{\circ}C$ or $110^{\circ}C$ inhibited the growth of cancer cell. Two agar hydrolysates prepared with 0.5% citrate and lactate at $110^{\circ}C$ for $180^{\circ}C$ min had relatively high cancer cell growth inhibition among the tested samples. The agar hydrolysates treated with citrate and lactate at $110^{\circ}C$ for 180 min obtained the main peaks of six and seven from Sephadex G-15 column chromatography. Among the main peaks, the cancer cell growth inhibition of C-3 and L-3 fractions were higher than that of other fractions.

• Food Science and Preservation
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• v.9 no.2
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• pp.240-247
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• 2002

This study, to enhance the sterilization, browning inhibition and precooling effect of electrolyzed oxidizing water(EOW) as cleaning water on food industry, was carried out to investigate the efficacy of electrolyzed oxidizing water(EOW) with 0.85% NaCl, 0.5% ethanol, polysorbate 80 of 1 ppm, 0.5% lemon juice and 0.5% citron juice. Escherichia coli KCTC 1039 with initial count of 5.63$\times$10$\^$8/ CFU/mL were reduced to <10$^1$CFU/mL after 15∼30 sec when it was treated by electrolyzed oxidizing water added with various food additives. Bacillus cereus KCTC 1012 were reduced to <10$^1$ CFU/mL after 2 minutes treatment with electrolyzed oxidizing water containing polysorbate 80 and ethanol. Iactobacillus plantarum KCTC 3108 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80, citron juice and lemon juice, respectively. Erwinia carotovora subsp. carotovora KCTC 2776 were reduced to <10$^1$CFU/mL after 30 sec treatment with electrolyzed oxidizing water containing polysorbate 80 and lemon juice. Browning inhibition effect was determined by comparison of polyphenol oxidase activity. Inhibition ratio of polyphenol oxidase was approximately 62∼84% in most treatments with the exception of 57% and 25% inhibition by 0.5% ascorbic acid and polysorbate 80, respectively. Sliced potato dipped in electrolyzed oxidizing water containing NaCl and citron juice for 30 minutes showed significantly low PPO activity, 64 units in treatment with NaCl and 91 units in treatment with citron juice. At the same time, changes in color value(△E) of sliced potato was below 3 in most treatments.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.283-288
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• 1995

This study was carried out to investigate the toxic action of herbicide, paraquat(1,1'-dimethyl-4,4'-bipyridylium-dichloride), against microorganisms. The toxic effect of paraquat was observed mainly using Escherichia coli(KCTC 1039), as follows; Growth of aerobic microorganisms which comprise 4 strains of bacteria and 2 strains of yeast and 4 strains of mold was inhibited drastically in the presence of 1.0mM paraquat But the growth of anaerobic bacteria was not affected by the chemical. When actively growing cells of E. coli were exposed to the paraquat at the concentration higher than 1.0 mM, they rapidly lost their ability to form colony and clearly formed inhibitory zone by well test More than 50% of the cells were killed by 1.0 mM paraquat treatment, even at immediate addition of paraquat to the medium.

• Journal of Food Hygiene and Safety
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• v.24 no.1
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• pp.46-49
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• 2009

The desmutagenic activity of the water extract of Cassia tara L on the mutagenicity induced by 4-nitroquinoline 1-oxide (4-NQO) and N-methyl-N-nitro-N'-nitrosoguani-dine (MNNG) was studied using the SOS Chromotest with Escherichia coli PQ37. The inhibition rates of water extract of Cassia tara L. at concentration of $100{\mu}g$/assay were 27.5% and 40% against 4-NQO and MNNG. The water extract of Cassia tara L. was separated into methanol soluble and methanol insoluble parts. The methanol soluble part exhibited higher inhibition effects than the methanol insoluble part against the mutagenic activities of 4-NQO and MNNG. Step-wise fractionation of methanol soluble part was done to obtain methanol, ethyl acetate and water fractions. Among these fractions, water fraction had the strongest inhibitory effects of 23.0 and 19.0% against mutagenicities of MNNG and 4NQO, respectively. The results clearly indicated that the water fraction showed much stronger antimutagenicity against MNNG than 4NQO. The inhibition rates of aqueous fraction of methanol-soluble from water extracted Cassia tara L. at concentrations of 1.0, 10, 100 and $250{\mu}g$/assay were 8.0%, 12.0%, 25.5% and 43.0%, respectively. The water fraction showed the inhibitory effects with dose response against the mutagenic activities induced by MNNG.

• Journal of Pharmacopuncture
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• v.9 no.3 s.21
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• pp.97-104
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• 2006

Objectives : This study was conducted to compare antibacterial activities and free radical scavenging activity between the Bee Venom and Sweet Bee Venom in which the allergy-causing enzyme is removed. Methods : To evaluate antibacterial activities of the test samples, gram negative E. coli and gram positive St. aureus were compared using the paper disc method. For comparison of the antioxidant effects, DPPH(1,1-diphenyl-2picrylhydrazyl) free radical scavenging assay and Thiobarbituric Acid Reactive Substances(TBARS) assay were conducted. Results : 1. Antibacterial activity against gram negative E. coli was greater in the Sweet Bee Venom group than the Bee Venom group. 2. Antibacterial activity against gram positive St. aureus was similar between the Bee Venom and Sweet Bee Venom groups. 3. DPPH free radical scavenging activity of the Bee Venom group showed 2.8 times stronger than that of the Sweet Bee Venom group. 4. Inhibition of lipid peroxidation of the Bee Venom group showed 782 times greater than that of the Sweet Bee Venom group. Conclusions : The Bee Venom group showed outstanding antibacterial activity against gram positive St. aureus, and allergen-removed Sweet Bee Venom group showed outstanding antibacterial activity against both gram negative E. coli and gram positive St. aureus. For antioxidant effects, the Bee Venom was superior over the Sweet Bee Venom and the superiority was far more apparent for lipid peroxidation.

• Food Science and Preservation
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• v.11 no.1
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• pp.117-121
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• 2004

We investigated antimicrobial effects of commercial vinegar on the harmful food-born organisms. As a result, antimicrobial effects of brown rice vinegar showed stronger than persimmon and artificial vinegar. In 10${\mu}$L/mL concentration of brown rice vinegar was completely inhibited about 5 strains except for V. parahaemolyticus, it was inhibited 15${\mu}$L/mL concentration. Therefore vinegars were effective for inhibition acitivity against food borne organisms. S. aureus and E. coli treated with 25${\mu}$L/mL concentratioin brown rice vinegar was observed by scanning electron micrographs(SEM). The cells were expanede and a part of cell wall was completely destructed by brown rice vinegar.