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-The contents of total phenolics and flavonoids, antimicrobial and tyrosinase inhibition activities of five growth stages with four greenhouse-grown cucumber extracts were investigated. Total phenolic content was high in Jangjukcheongjang, Janghyeongnakhap and five growth stage(24～27 cm). The content of total flavonoid did not differ between cultivar or growth stages. Among the four cucumber cultivars, the extract of Janghyeongnakhap showed a relatively strong antimicrobial effect against Staphylococcus aureus. The inhibition zone against Staphylococcus epidermidis of the samples tested in this experiment was 8～12 mm. And the antimicrobial effects against Malassezia furfur was high in Jangjukcheongjang, and showed the highest by the inhibition zone of 14mm in three(17～20 cm) growth stage. The tyrosinase inhibition activity of cucumber extracts showed relatively high activity in Jangjukcheongjang and Sinjoeunbaekdadagi, followed by Janghyeongnakhap. From these results, we confirmed that the extract of cucumber has high antimicrobial and whitening efficacy, and that in the future, the cucumber will be increase the availability in the field of high-value cosmetic materials. Key words -

A new cleanup method for the determination of brominated flame retardants with an emphasis on polybrominated diphenyl ethers (PBDEs) has been developed for fish tissue sample. This method effectively reduces the sample pretreatment time, labor and required less solvent quantities relative to conventional methods. Freezing-lipid filtration procedure removes approximately 90 % of the lipids in the extract without any significant loss of the PBDEs. A multilayered silica gel column was used for further cleanup of the extracts after freezing-lipid filtration. Multilayered silica gel column chromatography eliminated most of the co-extracted interferences, such as residual lipids and fatty acids. The extracts were analyzed after cleanup by high-resolution gas chromatography/highresolution mass spectrometry using the isotope dilution method. Tissue samples with 1.6-8.0 and 8.0-40 ppb of PBDE were analyzed using both the sulfuric acid treatment and freezing-lipid filtration cleanup methods in order to evaluate the method performance. Sulfuric acid treatment did not detect 2,4-DiBDE, whereas freezing-lipid filtration detected 2,4-DiBDE but at 50 % recovery. To compare the method, WMF-01 was analyzed via both the sulfuric acid treatment and freezing-lipid filtration cleanup.

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The objective of this study was to carry out the effect of seedling age on plant growth characteristics, photosynthetic rate, and the antioxidant enzyme activity of tomato(Lycopersicon esculentum Mill.) grown in a greenhouse. Forty-, forty-five-, fifty-, fifty-five, and sixty-day old seedlings from sowing to planting were planted in soil culture and grown in a greenhouse for ten weeks. Tomato growth and development of shorter seedling period less than 50-day old seedling was promoted, but plants with longer seedling period more than 50-day old seedling were decreased. At week 4, photosynthetic rates were lowest in 40-day old seedling age and there were no significant difference between treatments at week 8 after planting. Activities of antioxidant enzymes such as superoxide dismutase(SOD), catalase(CAT), ascorbate peroxidase(APX), and peroxidase(POX) were investigated. SOD activity was higher in 40-and 45-day old seedlings compared to other seedling ages at week 4 after planting. The highest CAT activity was investigated in 45-day old seedling at both 4 and 6 weeks after planting. At week 6 after planting, APX and POX was increased with increase of seedling ages from 50 to 60 days. Tomato yield was significantly increased with decreasing seedling age from 50-to 40-day old seedling ages. Hence it is considered that the optimum seedling age for tomato plant growth and yield was 40-to 50-day old seedlings. These results suggest that tomato plants with shorter seedling age less than 50-day old seedling promoted plant growth and productivity of tomato and then it would reduce production costs under soil culture.