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Differential sensitivity to paraquat was observed between cucumber cultivars and leaf age. Physiological responses to paraquat, including antioxidative enzyme activity, were investigated in leaf age classes of cucumber to identify mechanisms of paraquat tolerance. Leaf injury for ‘Naeseosamcheok’, ‘Daehandadagi’, ‘Baekgwangdadagi’, ‘Sangrokheukjinju’, and ‘Eunseongbaekdadagi’ cultivars was less than that of six other cultivars tested, averaged over leaf age and herbicide rate. The level of foliar injury caused by paraquat was Leaf 1 > 2 > 3 > 4 in seven of 11 cultivars used, where 4 was the youngest leaf. There was a positive correlation between leaf age and its relative susceptibility to paraquat, regardless of growth stage. Lipid peroxidation was less in the youngest leaf (Leaf 4) than in the older leaves at all herbicide concentrations. The youngest leaf had higher values for apparent photosynthesis than the oldest leaf. Differential leaf response to paraquat was partially correlated with the change in superoxide dismutase, ascorbate peroxidant, and glutathione reductase activities in treated leaves. Enzyme activity of ascorbate peroxidase (APX) was higher in Leaf 4 than in Leaves 1, 2, or 3 in untreated plants and after exposure to paraquat. APX isozymes were more abundant in treated than in untreated leaves and produced in higher amounts in younger than in older leaves. Application of ascorbate and glutathione before paraquat treatment protected cucumber leaves from paraquat injury.

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-This study was conducted to clarify the antimicrobial effects and radical scavenging activities of the cosmetic compositions having the natural plant pigments, and to enhance the natural materials utilization of cosmetics. The antimicrobial activities of the fifteen kinds of cosmetic composition having natural plant pigments were evaluated using the agar diffusion method. Most of the cosmetic composition having the natural pigments showed the clear zone formation of growth inhibition against Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus and Aspergillus flavus. Especially, purple sweet potato, bitter melon, mulberry leaf and gromwell showed the higher antimicrobial activities. All the cosmetic compositions were evaluated for their antioxidant activity using DPPH radical scavenging capacity and nitrite scavenging ability activity. Both of the free radical DPPH and nitrite scavenging ability was the highest in the cosmetic compositions of onion peel, and these antioxidant activity was significant differences according to different plant pigments. In this study, we conjectured that the plant pigment had the potent biological activities, therefore these plant resources having functional components could be a good materials for development into source of natural cosmetics. Key words -