• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.398-402
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• 1994

The participation of thermostable amylase in the decrease of viscosity of pine nut's porridge was investigated using the crude enzyme obtained from ammonium sulfate fractionation of pine nut extracts. The fraction precipitated at $35{\sim}55%$ saturation of ammonium sulfate had the highest specific activity of the enzyme. ${\alpha}-amylase$ activity was maximal at $75^{\circ}C$, pH 5.4. Amylograph data showed that addition of the enzyme to rice flour resulted in the significant decrease of its viscosity, suggesting the existence of thermostable ${\alpha}-amylase$ in pine nut.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.1.1-11
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• 1992

To find heavy metal-specific effects on the photosynthetic apparatus of higher plants, we investigated effects of $CuCl_2$, HgCl_2$ and $ZnCl_2$ on electron transport activity and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings. Effects on some related processes such as germination, growth and photosynthetic pigments of the test plants were also studied. Germination and growth rate were inhibited in a concentration-dependent manner by these metals. Mercury was shown to be the most potent inhibitor of germination, growth and biosynthesis of photosynthetic pigments of barley plants. In the inhibition of electron transport activity, quantum yield of PS II, and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings, mercury chloride showed more pronounced effects than other two metals. Contrary to the effects of other two metals, mercury chloride increased variable fluorescence significantly and abolished qE in the fluorescence induction kinetics from broken chloroplasts of barley seedlings. This increase in variable fluorescence is due to the inhibition of the electron transport chain after PS ll and the following dark reactions. The inhibition of qE could be attributed to the interruption of pH formation and do-epoxidation of violaxathin to zeaxanthin in thylakoids by mercury. This unique effect of mercury on chlorophyll fluorescence induction pattern could be used as a good indicator for testing the presence and/or the concentration of mercury in the samples contaminated with heavy metals.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1265-1274
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• 2015

Secondary metabolite-based chemotaxonomic classification of Streptomyces (8 species, 14 strains) was performed using ultraperformance liquid chromatography-quadrupole-time-offlight-mass spectrometry with multivariate statistical analysis. Most strains were generally well separated by grouping under each species. In particular, S. rimosus was discriminated from the remaining sevens pecies (S. coelicolor, S. griseus, S. indigoferus, S. peucetius, S. rubrolavendulae, S. scabiei, and S. virginiae) in partial least squares discriminant analysis, and oxytetracycline and rimocidin were identified as S. rimosus-specific metabolites. S. rimosus also showed high antibacterial activity against Xanthomonas oryzae pv. oryzae, the pathogen responsible for rice bacterial blight. This study demonstrated that metabolite-based chemotaxonomic classification is an effective tool for distinguishing Streptomyces spp. and for determining their species-specific metabolites.

• Journal of Microbiology and Biotechnology
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• v.24 no.3
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• pp.346-353
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• 2014

The chlorophyll-related compound pheophorbide a (Pa) was successively purified from an edible red seaweed, Grateloupia elliptica, using silica, octadecyl silica column chromatography and reversed phase-high-performance liquid chromatography, as well as the cell cycle inhibitory and apoptotic effects of Pa being investigated in U87MG glioblastoma cells. The Pa exhibited strong anticancer effects in the absence of direct photo-irradiation against various cancer cell lines, including U87MG, SK-OV-3, and HeLa cells. Among the cancer cells, the strongest anticancer activity of Pa exhibited on U87MG cells with $IC_{50}$ values of 2.8 ${\mu}g/ml$. In addition, Pa specifically had cytostatic activity on glioblastoma cells rather than human umbilical vein endothelial cells. Analysis of the cell cycle distribution showed that Pa induced G0/G1 arrest of U87 MG cells. In addition, arrested cells induced late apoptosis and DNA degradation under dark condition. These results suggest that Pa isolated from G. elliptica is a potential glioblastoma-specific anticancer agent without side effects on normal cells.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.89-93
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• 1998

Tomato phenylalanine ammonia-lyase 5 (tPAL5) was identified that alternate initiation sites were utilized differentially in response to environmental stimuli (Lee et al, 1992b). In this study, we tried to look into tissue -or cell- specific expression pattern of tPAL5 gene by fusing with ${\beta}-glucuronidase$ (GUS) gene in transgenic tobacco plants. In transgenic plants, root and stem extracts contained 8~12 fold higher levels of GUS activity than petiole or leaf tissue while the highest levels of induction was observed from leaf tissue by mechanical wounding (5~11 fold). In trans-sections of stems and petioles, GUS activity was restricted to phloem cells(outer region) of developing vascular bundle and mainly at apical tip region in the root tissues. The levels of GUS activity was drastically reduced (10~12 fold reduction) when the 5'-upstream region of tPAL5 gene (-1151bp from ATG codon) was deleted up to -665. The levels of GUS expression, however, raised up by 6~8 fold when deleted up to -455. Therefore, we conclude that there are positive cis-elements at the region -1151 to -1008 and at -455 to -195 while the negative cis-element is at -1008 to -455.

• Journal of Dairy Science and Biotechnology
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• v.39 no.1
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• pp.36-50
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• 2021

This study aimed to evaluate the biological potential of functional food, i.e., specific peptides obtained from the hydrolysis of milk protein, by assessing their antioxidant and antibacterial properties. For the preparation of casein hydrolysates, commercial enzymes were added to 10% casein solution in a 1:200 (w/v) ratio, and samples were collected each hour. Based on the assessment of the degree of hydrolysis (DH) of casein hydrolysates, it was observed that the concentration of all enzymatic hydrolysates increased rapidly from 30 to 40 minutes. However, no change was observed in their concentrations after 150 minutes. Protamex® and Neutrase® exhibited the highest DH when compared to other enzymes. Furthermore, SDS-PAGE was performed for analyzing the proteolytic pattern of each enzyme, except for Flavourzyme®, and peptides in the size range of 20-25 kDa were identified. Subsequently, peptides produced by two enzymes were isolated using a preparative liquid chromatography system. Overall, NF3, NF4, PF5, and PF6 showed higher antioxidant potential than other peptide fractions. Moreover, NF7 and PF3 exhibited the highest antibacterial activity. In this study, we evaluated the biological potential of novel casein-derived peptides that may find application in the food and healthcare industry.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.714-716
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• 1991

• Journal of Plant Biotechnology
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• v.6 no.1
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• pp.63-67
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• 2004

A simple procedure for the extraction of the lipolytic enzyme from rice bran has been developed. High activity of lipolytic enzyme was obtained by first defatting the rice bran to remove lipid components with various extraction conditions. Then, after rove cycles of aqueous extraction, rice bran lipolytic enzyme was purified using micro- and ultrafiltration apparatus. Lipolytic enzyme activity was estimated by its hydrolytic action of tributyrin. The result indicated that the standard activity curve of butyric acid showed that the potential rice bran enzyme is a hydrolytic lipase enzyme. In addition, it showed higher lipolytic activity and specific enzyme activity with further purification by micro- and ultrafiltration. The size of rice bran lipase enzyme was identified through 15 ％ SDS-PAGE. The molecular weight of the rice bran lipase enzyme was 41 kDa.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.33-42
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• 2002

Objective : This study was performed to investigate the activity of Whagan-Jeon (huaganjian) in protection against acetaminophen (AAP)-induced hepatotoxicity and the possible mechanisms in vivo. Methods : The following were performed : Serum ALT, depletion of hepatic glutathione (GSH) levels, the microsomal p. nitrophenol hydroxylation activity, microsomal aniline hydroxylation activity, genomic DNA fragmentation and its reversal, hepatic glutathione-S-transferase (GST) activity, and hepatic NAD(P)H:quinone oxidoreductase (QR) activity Results : Whagan-Jeon (huaganjian) protected against AAP-inducedhepatotoxicity by the increase of GSH levels, inhibition of P450 2E1-specific metabolic activities, attenuation of hepatic DNA damage, and induction of GST and QR activities in vivo. Conclusions : In conclusion, Whagan-Jeon (huaganjian) was effective in protection against AAP-induced hepatoxicity.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.357-360
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• 1997

The biological activity of monoglycerides, diglycerides, triglycerides and free fatty acids were investigated by the rice inclination test that is specific bioassay for brassinosteroids. The experimental results revealed that some diglycerides, triglycerides and free fatty acids as well as monoglycerides showed positive response. ${\alpha}-Monoolein$ and diolein as active principles showed higher activity than indole-3-acetic acid at the same concentration. From the results, it can be confirmed that the active principles are related to olein which especially have a high activity.