• Korean Journal of Food Science and Technology
• /
• v.29 no.1
• /
• pp.173-177
• /
• 1997

For the utilizing of tannins in the functional foods and natural inhibitor against browning reaction by tyrosinase in foods, inhibition effect against tyrosinase of tannins from Korean green tea was determined. Acetone extract from Korean green tea showed inhibition effect against tyrosinase. The gallocatechin compounds showed higher inhibition effect than the catechin compounds. In terms of stereo isomers, (-)-epicatechin compounds had higher inhibition effect than the (+)-catechin compounds. The monomer had higher inhibition effect than the dimer.

• Korean Journal of Childcare and Education
• /
• v.16 no.6
• /
• pp.71-88
• /
• 2020

Objective: The main purpose of this study was to investigate the direct effect of preschoolers' behavioral inhibition and indirect effects through maternal overprotective parenting and autonomy support on preschoolers' anxiety. Methods: A total of 295 preschoolers and their mothers were the subjects of this study. Mothers completed a questionnaire that included measures of their parenting behavior, preschoolers' behavioral inhibition and anxiety. Data were analyzed using structural equation modeling. Results: First, preschoolers' behavioral inhibition had a direct effect on their anxiety. Preschoolers with higher behavioral inhibition displayed higher levels of anxiety. Second, maternal overprotective parenting mediated the relationship between preschoolers' behavioral inhibition and anxiety. Third, maternal autonomy support mediated the relationship between preschoolers' behavioral inhibition and anxiety. Conclusion/Implications: The findings of this study emphasize the importance of reducing maternal overprotective parenting and promoting autonomy support to prevent preschoolers' anxiety. These findings could be used as a foundation for developing parent education programs for mothers with behaviorally inhibited preschoolers.

• The Korean Journal of Food And Nutrition
• /
• v.12 no.6
• /
• pp.559-563
• /
• 1999

Essential oil of Artemisia lavandulaefolia the chrysanthemum family plant used in the chinese medicine was extracted and antibacterial and antifungal activity with many kinds of the pathogenic bacterium and fungi was experimented by it. Ataphylococcus epidermidis and Streptococcus aureus gram positive bacterium at the concentration of 200ppm and Streptococcus mutans at the concentration of 1,000ppm showed the growth injibition effect of the cell. These showed statistically significant difference(p<0.05) Zymomonas mobilis Entrecoccus faecalis gram negative bacterium at the concentration of 200ppm and Pseudomonas putida at the concentration of 400ppm showedd the growth inhibition effect of the cell)p<0.05) V. Parahaemolyticus at the concentration of 800ppm and Pseudomonas aeruginosa at the concentration of 1,000ppm showed the growth inhibition effect of the cell(p<0.05) Candida albicans and Cryptococcus neoformans yeast-type fungi showed the gorwth inhibition effect of the cell at the concentration of 200ppm(p<0.05) Altenaria mali Aspergillus nidulans and Fusarium oxysporum filamentous fungi took the growth inhibition effect of the cell at the concentration of 600ppm, 400ppm, and 100ppm. respectively.

• Food Science and Preservation
• /
• v.9 no.4
• /
• pp.369-374
• /
• 2002

This study was performed to investigate the effects of tyrosinase inhibition, xanthine oxidase inhibition and nitrite-scavenging effects of gamma-irradiated Schizandrae Fructus extracts from different solvents. Schizandrae Fructus was extracted by hot water, ethanol, acetone and methanol, and the extracts were irradiated 10, 20 and 30 kGy with gamma rays. All extracts from Schizandrae Fructus showed inhibition effect against tyrosinase. Tyrosinase inhibition effect of Schizandrae Fructus were higher in solvent extracts than hot water extracts by irradiation. The Schizandrae Fructus extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging activity, which was measured at various pH conditions (1.2, 3.0, 6.0), was the highest in Schizandrae Fructus extracts at pH 1.2 and 3.0. Hot water extracts provided higher nitrite scavenging effect than those of the methanol, ethanol and acetone extracts. Gamma-Irradiation may not influence on biological activites of the extracts when irradiated up to 30 kGy.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.19 no.1
• /
• pp.1-10
• /
• 2006

This experimental study was performed to investigate the effect of herbal eye drops, Tangpo-san and Coptidis rhizoma on Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa keratitis. The following results were obtained by using Minimum inhibition Concentration(MIC) and inhibition Zone. 1. MIC on Staphylococcus aureus in Tangpo-san was 100%, in Coptidis rhizoma was 100% and in Cravit was 0.1% 2. MIC on Staphylococcus epidermidis in Tangpo-san was 100%, in Coptidis rhizoma was 10% and in Cravit was 0.1%. 3. MIC on Pseudomonas aeruginosa in Tangpo-san, Coptidis rhizoma was not showing and in Cravit was 0.1%. 4. The size of inhibition zone on Staphylococcus aureus for Tangpo-san was 13.3mm in $50{\mu}{\ell}$, for Coptidis rhizoma was 26mm in $50{\mu}{\ell}$ and for Cravit was 31mm in $50{\mu}{\ell}$, showing the highest antibacterial effect. 5. The size of inhibition zone on Staphylococcus epidermidis for Tangpo-san was 16mm in $50{\mu}{\ell}$, for Coptidis rhizoma was 25mm in $40{\mu}{\ell}$ and for Cravit was 34mm in $50{\mu}{\ell}$, showing the highest antibacterial effect. 6. The size of inhibition zone on Pseudomonas aeruginosa for Tangpo-san, Coptidis rhizoma was not and for Cravit was 24.7mm in $50{\mu}l$, showing the antibacterial effect. In addition, the results shows that the herbal eye drops, Tangpo-san and Coptidis rhizoma can be used to cure Staphylococcus aureus, Staphylococcus epidermidis keratitis and if further study is performed, the use of herbal eye drops will be valuable and beneficial in the clinical medicines.

• Journal of the Korean Society of Tobacco Science
• /
• v.9 no.2
• /
• pp.69-75
• /
• 1987

Nicotine, the main alkaloid of tobacco, showed different effect according to the enzyme. Among investigated enzymes, protease was inactivated remarkably by nicotine and the mode of inhibition was examined. $\alpha$-amylase and $\beta$-amylase were not affected, and cellulase and glucoamylase were inactivated partially when the concentration of it was over 1.0% , but protease was inhibited powerfully by nicotine The inhibition of protease by nicotine was performed almost in the initial stage of reaction, and was not so much affected by temperature, and was reversible. The inhibition type of protease by nicotine appeared as a Mixed-type inhibition.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.7
• /
• pp.1298-1307
• /
• 2008

In this study, we investigated the inhibition effects of single and mixed heavy metal ions ($Zn^{2+},\;Ni^{2+},\;Cu^{2+},\;and\;Cd^{2+}$) on iron oxidation by Acidithiobacillus ferrooxidans. Effects of metals on the iron oxidation activity of A. ferrooxidans are categorized into four types of patterns according to its oxidation behavior. The results indicated that the inhibition effects of the metals on the iron oxidation activity were noncompetitive inhibitions. We proposed a reduced inhibition model, along with the reduced inhibition constant ($\alpha_i$), which was derived from the inhibition constant ($K_I$) of individual metals and represented the tolerance of a given inhibitor relative to that of a reference inhibitor. This model was used to evaluate the toxicity effect (inhibition effect) of metals on the iron oxidation activity of A. ferrooxidans. The model revealed that the iron oxidation behavior of the metals, regardless of metal systems (single, binary, ternary, or quaternary), is closely matched to that of any reference inhibitor at the same reduced inhibition concentration, $[I]_{reduced}$, which defines the ratio of the inhibitor concentration to the reduced inhibition constant. The model demonstrated that single metal systems and mixed metal systems with the same reduced inhibitor concentrations have similar toxic effects on microbial activity.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.9
• /
• pp.1216-1220
• /
• 2001

Effect of hydroquinone (HQ) on rumen urease activity was studied. Hydroquinone at concentrations of 0.01 ppm, 0.1 ppm, 1 ppm, and 10 ppm inhibited urease activity of intact rumen microbes in vitro by 25%, 34%, 55% and 64% respectively. In the presence of low concentrations of $\beta$-mercaptoethanol, rumen urease could be solubilized and partially purified. The Km for the enzyme was $2{\times}10^{-3}$ M with Vmax of $319.4{\mu}moles/mg$ min. The kinetics of inhibition with partially purified rumen urease was investigated. The result showed that the inhibitory effect was not eliminated by increasing urea concentrations indicating a noncompetitive effect in nature with an inhibition constant $1.2{\times}10^{-5}$ M. Hydroquinone at the concentration of 10 ppm produced 64% urease inhibition, did not affect ruminal total dehydrogenase and proteolytic enzyme (p>0.05), but increased cellulase activity by 28% (p<0.05) in vitro. These results indicated that hydroquinone was a effective inhibitor of rumen urease and could effectively delay urea hydrolysis without a negative effect. The inhibitor appeared to offer a potential to improve nitrogen utilization by ruminants fed diets containing urea.

• Journal of Gifted/Talented Education
• /
• v.25 no.4
• /
• pp.469-491
• /
• 2015

The present study investigated the inhibition mechanisms of gifted children, which is one of the main executive functions in human cognitive system. The inhibition process was subdivided into cognitive and emotion aspects in order to examine the interplay between these two aspects with respect to inhibition processing. In Experiment 1, word-color Stroop task was used to study the cognitive inhibition process of 100 gifted children(Gender: 62 males, 38 females; Academic grade: 46 Elementary school students, 54 Secondary school students). In addition, emotional Stroop task was utilized in Experiment 2 to examine the effect of emotional component during cognitive inhibition process. Results revealed a significant cognitive cost (i.e., word-color Stroop effect) when participants had to withhold automatic response during cognitive inhibition task in Experiment 1. Such cognitive cost was reduced as the chronological age of the participants increased, with no difference in gender. The results in Experiment 2 showed no significant emotional inhibition cost (i.e., emotional Stroop effect) during cognitive inhibition task, and there was no effect of gender nor age. This suggests that the emotional component conveyed in words did not lead to cognitive bias effects. This study proposes that the cognitive and emotional inhibition processes are seemingly independent mechanisms that engage in complex interactions during inhibition processing of behavioral response.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.5
• /
• pp.987-992
• /
• 1998

This study was investigated to observe the cytotoxicity effect of Ligularia fischeri extracts against cancer cell lines including human lung carcinoma(A549), human cervix epitheloid carcinoma(HeLa) and human hepatocellular carcinoma(HepG2) using SRB(sulforhodamine B) method. The ethanol and methanol extracts of 1$\mu\textrm{g}$/${mu}ell$ showed approximately 79.2% and 86.4% cytotoxicity effects on HepG2 cell line and the ethyl acetate fracton fractionated from ethanol extracts showed the strongest cytotoxicity effect with 94% inhibition. The inhibitory effect of ethanol extract on HeLa cell line was somewhat low with 50~56% inhibition, but ethyl acetate fraction showed higher cytotoxicity effect with 91% and 91.9% inhibition on the HeLa and A549 cell line. On the contrary, the ethanol and methanol extracts showed the lower inhibition effects on the normal liver cell, WRL68, compared to human cancer cell lines.