• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.246-253
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• 2016

The antibacterial activities of thirty mushroom species belonging to Basidiomycetes and Ascomycetes, cultivated on two liquid media, were evaluated against gram-positive (Bacillus subtilis and Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria by the disk diffusion method. All of the mushrooms, except Auriporia aurea, Fomes fomentarius, and Lyophyllum shimeji, showed different antibacterial activity levels—from 9.5 mm in diameter of the inhibition zone to full inhibition of growth of the test bacteria. The antibacterial activities of Crinipellis schevczenkovi, Hohenbuehelia myxotricha, Oxyporus obducens, and Spongipellis litschaueri were observed for the first time. The antibacterial potential of culture liquids of the investigated species was higher than that of their mycelia activity. Dependence of the intensity of antibacterial activity on the culture medium was shown. The antibacterial efficiency of the most active species (Lentinus edodes, Piptoporus betulinus, and Phellinus igniarius) was verified and compared with those of some commercial antibiotics and natural essential oils of Salvia and Eucalyptus. The culture liquid of Piptoporus betulinus, obtained after cultivation on glucose-peptone-yeast culture medium, is a potential substance for further creation of antibacterial products.

• Journal of Nutrition and Health
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• v.32 no.7
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• pp.838-843
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• 1999

Antitumor effects of various teas have been studied for a long time. Among them, green tea is one of the most popular test and very close to our lives in Korea. However, precise effect and mechanism about antitumor effects of green tea were not estabilished. The present study investigated the antitumor effect of catechin, which is main component of green tea, which was produced in Korea, was used. In each group, morphological changes were observed induced severe cell damage and growth inhibition gradually until 24hours. Then catechin effect was found to be concentration-and time-dependent. EATC was injured abruptly at 100ug/ml catechin treatment for 6 hours and the effect lasted constantly until 24 hours. But in both of cell lines, cell damage and inhibition of proliferation did not show up apparently at concentration of 10 and 1ug/ml. In contrast, catechin led to little or no effect against HepG2 in all of concentrations and periods. These results suggest that catechin extracted from green tea had different effect on cancer cells as cell type, concentration and period. Therefore green tea would be helpful to cancer treatment as well as cancer prevention and this study would be the basic source for further research of green tea.

• Natural Product Sciences
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• v.9 no.4
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• pp.299-303
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• 2003

For the screening of inhibitors of sterol biosynthesis from natural products, a simple and rapid assay method was developed using recombinant yeast carrying human lanosterol synthase, main target of this assay method. Sterol biosynthesis inhibition activity was monitored only by the inhibition of growth of the recombinant yeast. By changing the substrate, this assay method can figure out which step is inhibited in the sterol biosynthesis by the test material. With this assay method total 102 plant samples were screened for their inhibitory activity of sterol biosynthesis. Among plant water extracts screened, 11 plant samples showed inhibitory activity on sterol biosynthesis in ergosterol (-) medium. For selection of the specific inhibitory materials, 11 plant samples were reassayed in ergosterol (+) medium. After all 5 plant samples, Abutilon avicennae Gaertn. (stem), Alnus japonica Steud. (stem), Amaranthus mangostanus L. (aerial part), Philadelphus schrenckii Pupr. (leaf) and Pimpinelia brachycarpa Nakai (aerial part), showed specific inhibitory activity.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1582-1585
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• 2004

The antioxidative ability on the basis of reduced glutathione sulphydryl level, the inhibition activities of linoleic acid peroxidation of cell free extract of Lactobacillus spp. and the effects of types of media and growth phase of the cells on the cellular GSH level have been determined. Correlation between reduced glutathione sulphydryl level and antioxidative ability of Lactobacillus spp. was analyzed: Lactobacillus casei HY 2782 contained 25.15 $\mu$mole/g of GSH, the cellular GSH level of L. casei HY 2782 reached maximum after 24 h of cultivation and tended to decrease on further cultivation up to 72 h. There was a significantly higher level of cellular GSH when grown in de Man Rogosa and Sharpe (MRS) broth than in tryptone phytone yeast extract (TPY) broth or bromcresol pruple dextrose (BCP) broth (p<0.05). The antioxidant activity of cell free extract of Lactobacillus spp. have been shown to be significantly different among strains in the inhibition of linoleic acid peroxidation by thiobarbituric acid (TBA) test (p<0.01). L. casei HY 2782 and L. acidophilus ATCC 4356 revealed a high degree of antioxidative effect in linoleic acid oxidation system. Spearmans' rank correlation coefficient between inhibitory activity on linoleic acid peroxidation and cellular GSH levels of Lactobacillus spp. was 0.65, which means a significant positive correlation.

• Journal of the Mineralogical Society of Korea
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• v.23 no.1
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• pp.51-61
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• 2010

Ettringite $(Ca_6[Al(OH)_6]_2(SO_4)_3{\cdot}26H_2O)$ is a sulfate mineral that shows a complicate property in concrete. It is often called as "a cancer of concrete" because secondary ettringite formation in hardened concrete often cause expansion and cracking of concrete due to its expansive crystal structure. In the present study, we tested the possibility for crystal growth inhibition of secondary ettringite by crystallization inhibitors that are commercially used for scaling inhibitors in Korea. For the test, we developed a method of ettringite solution synthesis. Three types of crystallization inhibitors were selected and examined the effects On ettringite growth inhibition. The experimental results of ettringite solution synthesis indicated that ettringite was successfully synthesized under condition that the mass balance between calcium hydroxide saturated solution and aluminum sulfate solution was attained. Monosulfate and semisulfate were synthesized when the ratio of $Ca^{2+}$ ions to ${SO_4}^{2+}$ ions was increased. The induction time of ettringite crystallization was less than 2 min. and crystallization was almost completed within an hour. The experimental results of ettringite crystallization inhibition showed that organic PBCT (2-Phosphonobutane-1,2,4-Tricarboxylic Acid) and inorganic SHMP (Sodium Hexametaphosphate) were relatively less effective on ettringite crystallization inhibition under experimental conditions. However, organic HEDP (1-Hydoxyethylidene-1,1-Diphosphonic Acid) effectively prevented ettringite growth with producing amorphous gel phase materials up to inhibitor concentration 0.1 vol.% of aluminum sulfate solution.

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.837-842
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• 2007

This study was conducted to test the effect of residual Al on plankton community after dissolved air flotation (DAF) application. Growth rate of phytoplankton after DAF application ($0.37day^{-1}$) was about 2 times lower than that before DAF application ($0.70day^{-1}$). Under the condition of addition of nitrogen and phosphorus without light, growth rate phytoplankton in treatment without residual Al increased in difference with showing the negative growth rate in treatment with residual Al. Under the condition of light without addition of nutrient, growth rate of phytoplankton was no noticeable difference between the before and after DAF application. The relatively high settling rate (0.47 m/day) was observed in treatment after DAF application. Although the abundance of rotifer decreased, the abundance of copepod and cladoceran such as Daphnia galeata, Diaphanosoma sp. and Bosmina longirostris with relative higher grazing was no noticeable difference between the before and after DAF application. In the treatments before and after DAF application with zooplankton, growth rate of phytoplankton was $0.41{\pm}0.08day^{-1}$, $0.20{\pm}0.03day^{-1}$, respectively. This difference was in treatment after DAF application similar with those in treatments before and after DAF application without zooplankton. Those indicate that the filter-feeding effect of zooplankton on phytoplankton community may be not changed by residual Al after the DAF application. These results suggest that residual Al after DAF application be to improve water quality by inhibition of growth rate as well as increasing settling rate of phytoplankton.

• Korean Journal of Weed Science
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• v.15 no.2
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• pp.121-130
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• 1995

Greenhouse and laboratory studies were conducted to investigate allelopathic potential of some weed species on alfalfa(Medicago sativa L.) germination and seedling growth. In the comparison between top(leaves+stems) and root extracts, top extract exhibited greater allelopathic effects on alfalfa germination than that of root. The various weed species extract differently responded to alfalfa test species, WL-320, in terms of allelopathic effect. Top and root aqueous extracts of lambsquarter(Chenopodium album L.), giant foxtail(Setaria faberii Herrm.), redroot pigweed (Amaranthus retroflexus L.), velvetleaf(Abutilon theophrasti Medic.), crabgrass(Digitaria sanguinalis L.), canada thistle(Cirsium arvense L.) and prostrate knotweed(Polygonium aviculare L.) significantly inhibited germination, seedling length, weight, vigor, and rate of germination of alfalfa. The regression slopes of various top extracts showed that velvetleaf(b=3.69) extracts were the most inhibitory, while large crabgrass(b=2.39) extracts had the least allelopathic effect on alfalfa germination. Germination, seedling length and weight of alfalfa were inversely proportional to the concentration of dried velvetleaf extracts. Also, more of the toxic effects were observed from the dried extracts compared to the fresh extracts. Residue of velvetleaf inhibited significantly alfalfa emergence and survival percentage compared to the control. The emergence and survival percentage of alfalfa were 44%, 57% at 1.0% residue treatment, respectively. When weed residues were mixed with silica sand with incubation time, velvetleaf residue most inhibited alfalfa growth. The degree of inhibition increased as incubation time increased. An incubation for 72h caused the greatest inhibition of alfalfa growth. These results demonstrate the different allelopathic activity of weed species extracts on alfalfa and suggest that weed may affect alfalfa growth and development through the inhibitory effects of allelochemicals present in weed tissue.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.135-141
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• 2007

To increase the consumer acceptability of yam and the shelf-life of fresh-cut yam, organic acid-treated fresh-cut yam was prepared. When uncontaminated fresh-cut yam was stored at $4^{\circ}C$ for 14 days after treatment with 1% (v/w) organic acids, the browning and microbial putrefaction of fresh-cut yam were inhibited by treatment of acetic acid or maleic acid, whereas treatment of citric acid and ascorbic acid, commonly used browning inhibitors in food industry, did not show apparent effects on the browning and putrefaction of yam. The Inhibitory effects of acetic acid or maleic acid were superior than those of NaOCl (100 ppm), hydrogen peroxide (100 ppm) or commercially available washing solution. Also, treatments of 1% acetic acid, or 1% maleic acid Into artificially-contaminated yam $(10^5\;CFU/g-yam)$ showed strong inhibition of browning and putrefaction during long term storage at $4^{\circ}C$. The growth inhibition test indicated that 0.1% is enough to inhibit the growth of psychrotrophic yam-putrefactive Pseudomonas sp., and treatment of 0.1% acetic acid, or 0.1% maleic acid inhibited the browning and microbial putrefaction of fresh-cut yam. Our results suggested long-term distribution of yam or other root crops products is possible by treatment of organic acid, such as acetic acid, combined with aseptic vacuum packaging technology.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.1
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• pp.25-40
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• 2013

Objectives: The object of this study was to observe the in vitro antibacterial effects of five single(Pulsatillae Radix, Patrinae Radix, Sanguisorbae Radix, Sophorae Flos, and Sophorae Radix) aqueous herbal extracts, traditionally used for treating various gynecological diseases including mastitis in Korea, against Staphylococcus aureus. Methods: Antibacterial activities against Staphylococcus aureus of aqueous extracts of Pulsatillae Radix, PatrinaeRadix, Sanguisorbae Radix, Sophorae Flos, and Sophorae Radix were detected using standard agar microdilution methods. In addition, the effects on the bacterial growth curve were also monitored at Minimal Incubation Concentration(MIC) and $MIC{\times}2$ levels. The effects on the intracellular killing and bacterial invasion of individual test materials were also observed using murine macrophage(Raw 264.7) and human mammary gland carcinoma cell(MCF-7). Results: MIC of aqueous extracts of Pulsatillae Radix, Patrinae Radix, Sanguisorbae Radix, Sophorae Flos, and Sophorae Radix against Staphylococcus aureus were detected as $0.215{\pm}0.107$ mg/ml, $0.273{\pm}0.107$ mg/ml, $0.469{\pm}0.297$ mg/ml, $11.850{\pm}8.406$ mg/ml, and $0.664{\pm}0.546$ mg/ml, respectively. MIC of Ciprofloxacin was detected as $0.469{\pm}0.297{\mu}g/ml$ at same conditions. In addition, all five single aqueous herbal extracts were also showed marked dosage-dependent inhibition of bacterial growth. The effects of intracellular killing with Raw 264.7 and inhibition of bacterial invasion with MCF-7 cells were detected, in the order of Sophorae Flos, Pulsatillae Radix, Patrinae Radix, Sanguisorbae Radix and Sophorae Radix aqueous extracts in the present study. Conclusions: The results obtained in this study suggest that all five single aqueous herbal extracts showed antibacterial effects against Staphylococcus aureus and they also showed dosage-dependent inhibitory effects on the bacterial growth. They showed the significant intracellular killing and inhibition of bacterial invasion effects. It means, all five single aqueous herbal extracts may show potent anti-infectious effects against Staphylococcus aureus for mastitis.

• Journal of Life Science
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• v.20 no.10
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• pp.1505-1510
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• 2010

In this study, we investigated antimicrobial- and anticarcinogenic activities of Amphitrite albicostatu (AA) fractions. AA was extracted with methanol first and then further fractionated into four different types: hexane (AAMH)-, methanol (AAMM)-, buthanol (AAMB)- and aqueous (AAMA) partition layers. In the paper disk test, the antimicrobial activity of AA fractions increased in proportion to concentration. Among the various solvent fractions, only AAMB showed antimicrobial activity. We also determined the growth inhibition and quinone reductase (QR) induced effects of AA fractions on cancer cells. The growth inhibition effects of AA fractions on HepG2 and B16F10 cells were evaluated by MTT assay. AAMM showed the strongest growth inhibition effects on HepG2 and B16F10 cells. The quinine reductase (QR) induced effects of AAMM on HepG2 cells at 100 ug/ml concentration indicated it to be 2.04 times higher than the control values of 1.0. Although further studies are needed, the present work suggests that Amphitrite albicostatu (AA) could have a potential use as a food preservative and chemopreventive agent.