• 한국미생물·생명공학회지
• /
• 제22권6호
• /
• pp.621-626
• /
• 1994

Cysteine showed strong inhibitory effect on growth and protease production of Pseudo- monas sp. RP-222 and its mutant, MR-3966. Mid- to late-log phase cells were most sensitive to the presence of 10 mM cysteine. The inhibition caused by cysteine was almost completely overcome by addition of isoleucine, leucine and valine mixture to the medium, and inclusion of iso#leucine alone could greatly reduce the inhibitory effects of cysteine. Homocysteine and #cysteine, sulfur compounds having similar structure as cysteine, inhibited to varying degrees the growth of both strains. Cysteine and homocysteine were strong inhibitors of threonine deaminase but not transa#- minase B. These results suggest a relationship between the growth-inhibitory effects of cysteine and other sulfur compounds and the inhibition of isoleucine synthesis at the level of threonine deaminase.

• 한국조리학회지
• /
• 제9권4호
• /
• pp.69-80
• /
• 2003

To develope natural food preservatives antimicrobial effect of the natural products against food-related bacteria and yeast The purpose of this study was evaluate antimicrobial effect of the citrus seeds. antimicrobial activities of methanol extracts from the citrus seeds investigate against Escherichia coli O26, Staphylococcus aureus 6358, Saccharomyces cerevisiae IBM 4274, Bacillus licheuiformis 9945a and Alcoligenes faecalis. Citrus seeds is containing to moisture 4∼6.5%, curd protein 11∼15%, curd lipid 32∼46%, curd carbohydrate 22∼45 % and ash 2∼4 %, that is containing to flavornoid 12∼48mg% and phenolic compound 22∼53mg%. Solidity content of the methanol extract from the citrus seeds was 0.8∼1.2%. Almost all of the methanol extracts from citrus seeds exhibited growth inhibiting activities for most of microorganisms tested. The methanol extracts from Citrus grandis, C. sunki, C. sulcata showed the growth inhibitory effects against Escherichia coli O26. The methanol extracts from C. obovoidea, C. sulcata, C. aurantium showed the growth inhibitory effects against Staphylococcus aureus 6358. The methanol extracts from C. obovoidea, C. sulcata, C. tangerina showed the growth inhibitory effects against Saccharomyces cerevisiae IBM 4274. The methanol extracts from C. obovoidea, C sunki, C. sulcata, C. tangerinan, C. natsudaidai, C. iyo, C. aurantium showed the growth inhibitory effects against Bacillus licheuiformis 9945a. The methanol extracts from C. obovoidea, C sunki, C. sulcata, C. aurantium showed the growth inhibitory effects against Alcoligenes faecalis. Among this especially, Showed growth inhibiting activity of the methanol extracts from Citrus sulcata that about microorganisms investigated. If apply searching suitable application method about such the citrus seeds antimicrobial activity, role as good antimicorbial material in storage or cooking of food, processing is expected.

• 한국작물학회지
• /
• 제44권3호
• /
• pp.296-301
• /
• 1999

The concerns on the crop damage by ultraviolet (UV) radiations is increasing owing to the decrease of their absorbing stratospheric ozone in the tropospheric. Cultivar differences on early growth of UV radiation among five Korean rice cultivars, four japonica types and one Tongil type (indica-japonica cross hybrid), were studied. Pot-seeded rice plants were grown under four different radiation conditions, i.e., visible radiation only, visible radiation with supplemented with high or low dose of UV-B (280~320 nm in wavelength) and UV-C (less than 280 nm in wavelength). The inhibitory degree on plant height, shoot and root weight and length of leaf blade and leaf sheath were determined at 40 days after seeding. UV-C showed the most severe inhibitory effect on the degree of biomass gain and leaf growth in most cultivars examined, followed by high UV-B and low UV-B. Among the cultivars used, the Kuemobyeo was the most sensitive cultivar and had not repair or showed resistance ability to continued irradiation of UV radiation. However, Janganbyeo and Jaekeon showed different responses that the elongation of leaf blades was promoted on 2nd and 3rd leaves and inhibited on 4th and 5th leaves but this inhibitory degree was reduced on 6 th and 7th leaves. Such tendency on leaf growth means that both cultivars had low sensitivity and most resistant ability to continued irradiation of UV radiation. While Tongil showed different response to enhanced UV radiation, ie., low UV-B promoted leaf growth but the inhibitory was severely increased by continued irradiation of high UV-B and UV-C, which means that Tongil had high threshold of UV radiation for response as an inhibitory light of plant growth. The results of this study indicate that the differences on sensitivity or resistant to the effects of UV radiation were existed among Korean rice cultivars.

• 대한의생명과학회지
• /
• 제11권2호
• /
• pp.175-183
• /
• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• 한국치위생학회지
• /
• 제15권4호
• /
• pp.735-741
• /
• 2015

Objectives: Lentinus edodes is an edible mushroom with a variety of beneficial effects such as antitumor, anti-inflammatory, antioxidant, and immune-modulatory activity. This study was carried out to evaluate the antimicrobial activities of Lentinus edodes extracts against oral-related bacteria. Methods: The antimicrobial activities of this extracts were investigated against S. anginosus, S. sobrinus, S. aureus, S. mutans, S. ratti, S. sanguinis, A. viscosus, A. naeslundii, and A. actinomycetemcomitans by the disc diffusion method, minimum inhibitory concentration (MIC), and growth inhibition. Results: Ethanol extracts had no antimicrobial activities, but acetone extracts showed antimicrobial activities against A. viscosus and A. actinomycetemcomitans and ethyl acetate extracts had effects against S. aureus, S. sanguinis, A. viscosus, and A. actinomycetemcomitans. Conclusions: The inhibitory effect of Lentinus edodes extracts was investigated on the growth of A. viscosus. Ethyl acetate and acetone extracts showed 90% and 77% inhibitory effect, respectively, against A. viscosus for 24 hrs. Ethyl acetate extracts had MIC of 25.0 mg/ml and acetone extracts showed MIC of >25.0 mg/ml.

• Nutrition Research and Practice
• /
• 제1권4호
• /
• pp.273-278
• /
• 2007

The objective of this study was to evaluate the inhibitory activity of natural products, against growth of Escherichia coli (ATCC 25922) and Salmonella typhimurium (KCCM 11862). Chitosan, epigallocatechin gallate (EGCG), and garlic were used as natural bioactives for antibacterial activity. The testing method was carried out according to the disk diffusion method. All of chitosan, EGCG, and garlic showed inhibitory effect against the growth of E. coli and Salmonella typhi. To evaluate the antibacterial activity of natural products during storage, chicken skins were inoculated with $10^6$ of E. coli or Salmonella typhi. The inoculated chicken skins, treated with 0.5, 1, or 2% natural bioactives, were stored during 8 day at $4^{\circ}C$. The numbers of microorganisms were measured at 8 day. Both chitosan and EGCG showed significant decrease in the number of E. coli and Salmonella typhi in dose dependent manner (P < 0.05). These results suggest that natural bioactives such as chitosan, EGCG may be possible to be used as antimicrobial agents for the improvement of food safety.

• 한국식품영양과학회지
• /
• 제26권6호
• /
• pp.1258-1267
• /
• 1997

Corbon dioxide id effective for extending the shelf-life of perishable foods by retarding microbial growth. The overall effect of carbon dioxide is to increase both the lag phase and generation time of microorganisms. However, the role of carbon dioxide in affecting the growth and metabolism of any given microorganisms is not clear yet, although its inhibitory effect is generally found at moderate to high concentrations. Systematic studies of the effects of carbon dioxide on microorganisms are therefore warranted. It is also necessary to understand the role of carbon dioxide in the preservation of foods as well as the control by carbon dioxide of fermentations of biotechnological importance. In this review, the antimicrobial effect of carbon dioxide on microorganisms is investigated in terms of its gas and solution properties, inhibition of microbial growth and specific metabolic processes, perturbation of membrane structure.

• 대한본초학회지
• /
• 제22권2호
• /
• pp.65-72
• /
• 2007

Objectives : In this study, we investigate that Euphorbiae lathyridis Semen extract contributes to growth inhibitory effect and anti-cancer activity on the HT-29 human colon cancer cells. Methods : Euphorbiae lathyridis Semen was extracted from the Semen of the plant using 80% Methanol. The Euphorbiae lathyridis Semen extract was treated to different concentrations for 24 hr, 4Shr or 72hr. Growth inhibitory effect was analyzed by measuring FACS study and MTT assay. Cell apoptosis was confirmed by surveying caspases cascades activation using Westem blot. Results : Exposure to Euphorbiae lathyridis Semen extract (0.4mg/ml) results in an inhibitory effect on cell growth in HT-29 cells. Growth inhibition by Euphorbiae lathyridis Semen extract in HT-29 cells was related with the inhibition of proliferation and induction of apoptosis. The Euphorbiae lathyridis Semen extract induces DNA fragmentation in HT-29 cells. Furthermore, Euphorbiae lathyridis Semen extract induces cell apoptosis through the activation of caspases-3, caspase-9 and PARP cleavage. Conclusion : Euphorbiae lathyridis Semen extract induces apoptosis in human colon cancer cells, therefore, we suggest that Euphorbiae lathyridis Semen extract can be used as a novel class of anti-cancer drugs.

• 한국식품영양과학회지
• /
• 제24권2호
• /
• pp.305-312
• /
• 1995

Ixeris dentata was extracted with methanol and then the methanol extract was further fractionated to hexane, chloroform, ethyl acetate, butanol and aqueous fraction. The methanol extract of lxeris dentata had the strong antimutagenic effect on the aflatoxin B1(AFB1) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in Ames mutagenicity test and SOS chromotest. Among the solvent extracted fractions from the methanol extract, the chloroform fraction exhibited the greatest antimutagenic effect suppressing the mutagenicity of AFB1 with inhibition rate of 74 percent. The methanol extract of Ixeris dentata also revealed the inhibitory effect on the growth of MG-63 human osteosarcoma cells after 6 days of breeding at 37℃. The chloroform fraction and the ethyl acetate fraction from the methanol extract of lxeris dentata were most effective and inhibited the growth of MG-63 cells by 97 and 93 percent, respectively. It is suggested that the inhibitory effects of lxeris dentata on the mutagenicity and the growth of MG-63 human osteosarcoma cells are strong in the lipid soluble fractions.

• The Korean Journal of Ecology
• /
• 제19권4호
• /
• pp.295-304
• /
• 1996

KDICical substances from Artemisia scoparia were analyzed by gas chromatography. Seven phenolic compounds and thirty nine terpenoids were identified. Most abundant within each group were cinnamic acid and camphor, respectively. The KDICicals were prepared as aqueous extracts and then used for germination, growth, and chlorophyll content tests. The extracts were inhibitory to germination and seedling growth of the receptor lants. This inhibitory effect was dependent on concentration. When the effect of the aqueous extract on chlorophyll content was assayed, both chlorophylls a and b were shown to be reduced. The reduction in seedling elongation and growth in dry weight paralleled the reduction in chlorophyll concentration. These KDICical substances, including phenolic compounds and terpenoids, from Artemisia scoparia were responsible for the growth inhibition of the selected species.