• Journal of Life Science
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• v.34 no.1
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• pp.28-36
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• 2024

We evaluated the efficacy of Geranium thunbergii (GT), which has so far been understudied as a cosmetic material, and conducted anti-inflammatory-related activity studies. We measured the electron donation ability and ABTS⁺ radical scavenging ability to confirm the antioxidant ability of GT and found values of 91% and 94% at a concentration of 50 ㎍/ml, respectively, confirming that GT had excellent antioxidant ability. Tyrosinase inhibitory activity was measured to evaluate whitening activity, and it was found that inhibitory activity was 24.8% at the highest concentration of 1,000 ㎍/ml. Elastase and collagenase inhibitory activity were measured to determine the wrinkle improvement activity of the GT; 30.6% and 90% inhibitory activity were shown at the highest concentration of 1,000 ㎍/ml, respectively. Excellent inhibitory activity was confirmed through the measurement of collagenase inhibitory activity. Before the cell experiments were conducted, the survival rate of the macrophages Raw 264.7 according to GT treatment was determined based on the MTT assay, and the cell survival rate was greater than 83.6% at a concentration of 100 ㎍/ml. Subsequent cell-related experiments were conducted at concentrations of 100 ㎍/ml or less. The NO production inhibitory activity according to the GT treatment by NO assay was measured, and a 74.9% inhibitory rate was confirmed at a concentration of 100 ㎍/ml. Western blotting was performed to determine protein expression inhibition, and both COX-2 and iNOS factors were concentration-dependently inhibited in GT. Based on these results, GT is considered to have potential as an anti-inflammatory functional cosmetic material.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.384-388
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• 2010

Human microsomal prostaglandin E synthase-1 (mPGES-1) catalyzes the conversion of prostaglandin $H_2$ ($PGH_2$) into prostaglandin $E_2$ ($PGE_2$). To establish a stable and efficient method to assess the activity of mPGES-1, a coupled enzyme assay system using mPGES-1, 15-hydroxyprostaglandin dehydrogenase (15-PGDH) and phosphomolybdic acid (PMA) was developed. In this assay system, $PGH_2$ was converted to $PGE_2$ by mPGES-1, and then $PGE_2$ was further transformed to the 15-keto-$PGE_2$ by 15-PGDH accompanying the production of NADH, which was easily detected by fluorescence spectrometry in a multi-well plate format. During the reaction, spontaneous oxidation of $PGH_2$ was prevented by PMA. Using this novel assay, the $K_m$ value of mPGES-1 for $PGH_2$ and the $IC_{50}$ value of the previously characterized inhibitor, MK-886, were determined to be 0.150 mM and $2.8\;{\mu}M$, respectively, which were consistent with the previously reported values. In addition, low backgrounds were observed in the multi-wall plate screening of chemical compounds.

• Korean Journal of Plant Resources
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• v.22 no.4
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• pp.312-316
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• 2009

In the present study, the anti-cancer activity of 80% ethanol extracts from 120 kinds of medicinal herbs and native plants were investigated. Among them, the barks of Melia azedarach L. var. japonica Makino showed the highest cytotoxicity in HCT-15 human colon cancer cell. With this result, we carried out hollow fiber (HF) assay and anti-metastasis study to confirm the anti-cancer effects of M. azedarach var. japonica. In MTT assay, M. azedarach var. japonica.inhibited the proliferation of HCT-15 cells in dose-dependent manner. HF assay was carried out using A549 human adenocarcinoma cell, HCT-15 and SK-Hep1 human liver cancer cell via intraperitoneal (IP) and subcutaneous (SC) site. As a results, SK-Hep1 implanted in IP site showed the highest cytotoxicity. The result from metastatic model using B16/BL6 mouse corresponded to that of HF assay. These results suggest that the ethanol extract from M. azedarach var. japonica. might have a potent anti-cancer activity and advanced study is needed for the development of novel natural anti-cancer drug.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.332-336
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• 2005

Epoxide hydrolase activities of various microbial cells were analyzed by colorimetric assay based on alkylation of epoxides with 4-(p-nitrobenzyl)pyridine (NBP). The epoxide hydrolase activity was determined by measuring the decrease of color intensity at 560 nm due to the decrease of styrene oxide substrate by epoxide hydrolase-catalyzed hydrolysis reaction. The experimental conditions of NBP colorimetric assay were optimized for the efficient measurement of epoxide hydrolase activities from various microbial cells.

• Journal of Aquaculture
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• v.16 no.3
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.116-121
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• 2012

Water extract from Pinus densiflora (WPD) was investigated for its antioxidant activity and its ability to provide protection from DNA damage. A series of antioxidant assays, including a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assay, a reducing power assay, a metal-chelating assay, a superoxide radical scavenging assay, and a nitrite scavenging ability, as well as a DNA damage protection assay were performed. Total phenolic content was found to be 211.32 mg Tan/g WPD. The extract scavenged 50% DPPH free radical at a concentration of 21.35 ${\mu}g/mL$. At that same concentration, the reducing power ability of WPD was higher than that of ${\alpha}$-tocopherol. The extract chelated 68.9% ferrous ion at the concentration of 4 mg/mL. WPD showed better nitrite scavenging effect at the lower pH. Meanwhile, WPD exhibited a strong capability for DNA damage protection at 1 mg/mL concentration. Taken together, these data suggest water extract from Pinus densiflora could be used as a suitable natural antioxidant.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.74-74
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• 2019

The aim of the study was to determine the antioxidant activities of the plants with origin of the Far East. The Carlemannia tetragona Hook f., which is a species of plant in the family Carlemanniaceae and Celastrus virens which is a species of plant in the family Celastraceae were tested for antioxidant activities. Samples were prepared using 95% ethanol using DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical) assay for assessing the antioxidant activity. Ascorbic acid was used for positive control for DPPH assay. DPPH assay experiment showed that extracts of the Carlemannia tetragona Hook. f., and Celastrus virens might have anti-oxidant activity 54.5% and 258% higher, respectively, compared to control. To determine the cell toxicity of these plant extracts, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used. MTT assay experiment showed that Carlemannia tetragona Hook. f., and Celastrus virens might have less toxicity 23.3% and 27.5%, respectively, compared to control. Taken together, these experiments showed that Celastrus virens extracts might have much higher antioxidant activities than Carlemannia tetragona Hook. f., with relatively lower toxicity. This implies that this study might provide a basis to develop a new powerful antioxidant candidate for human diseases therapeutics.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.239-240
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• 2003

Type I (collagen) and procollagen are reduced in aged human skin. This reduction could result from increased degration by metalloproteinases and from reduced procollagen synthesis and skin collagenase is required for initiation of the degration of type I collagen. In the present study, we study on assay the collagen and collagenase in natural plants using the fibroblast human skin cell. We select the 15 kind of plants used to herbal and 4 kind of fraction(by methylene chloride, ethyl acetate, n-butanol, water). Among these extract, the ethyl acetate fraction from benincasa hispida/prunus persica, trichosanthes kiriowii, trogopterus xanthipes and methylene chloride fractions from benincasa hispida/prunus persica, torilis japonica and n-butanol fraction from cnidium officinale, chrysanthemum sibiricum were selected for further experiments as they exhibited distinctive amount of collagen compared to other natural extracts. These extracts were again subjected to collagenase assay test. Benincasa hispida/prunus persica extract was shown to have exellent collagen synthesis activity from result of the collagen assay test and the other extract was shown to have over 130% of collagen synthesis activity. But, in the study of collagenase assay test just only trogopterus xanthipes extract was shown to have collagenase inhibition.

• Journal of the Korean Chemical Society
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• v.12 no.4
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• pp.142-145
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• 1968

The relative activity of glucose-6-phosphate dehydrogenase in E. coli was measured at 340 $m\mu$ with a spectrophotometer. The synchronized E. coli cells in exponential phase were treated with Phage($T_2$) ghost, and used as a enzyme solution directly. This assay method supposed to be useful for the continuous determination of enzyme activity in E. coli.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.559-565
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• 1999

The two gericudranin E derivatives, GER-I & II, were synthesized and evaluated their antitumour activities for the elucidation of structure-activity relationship. 2,4,6-Trihydroxyacetophenone was converted to target molecules GER-I and GER-B in 5 steps via sequential protection, aldol condensation, Michael type-cyclization, regioselective C-benzylation. The cellular growth inhibition of compounds GER-I and GER-II were investigated against P388, L1210, K562, HCT-15, SK-HepG-1, MCF-7 as cancer cell lines and mouse splenocytes as a normal cell by MTT assay.