Background : Indigenous plant in Jeju island, Sasa quelpaertensis Nakai, belongs to the Bambusoideae and inhabit around Mt. Halla. According to the ancient book such as Dongui Bogam, Sasa quelpaertensis Nakai have been known to possess the antidiabetic, anti-inflammatory, and anti-diuresis effect. However, because of gradual upturning temperature, Sasa quelpaertensis Nakai was spread out to wider area and intrude the habitat that other plant species are growing. Recently, although the study to seek effective use of Sasa quelpaertensis Nakai, the investigation about functional properties has not been taken place enough. Methods and Results : To assess the inhibitory activity of melanin synthesis, we employ the tyrosine as substrate and measure the formation of dopaquione at 490 nm. Firstly, 0.1 mM potassium phosphate buffer and tyrosinase were mixed and incubated at 37℃. After incubating at 37℃, the absorbance rate was measured at 490 nm. The value was compared with positive control, arbutin, and calculated with the rate between sample and control value. Previously, formononetin, glabrene, glabridin, glabrol, artocarbene, dihydromoriin are known as effective substances for whitening. Moreover, the arbutin, which was separated from Arctostaphylos uva-ursi (L.) Sprengel, are widely used in cosmetic field. Arbutin inhibits tyrosinase and tyrosine synthesis, which induce blackish pigmentation. Practically, the Sasa quelpaertensis Nakai leaf ethanol extract depend on different solvent condition, whole extracts showed stronger inhibition than arbutin. Especially, 60% ethanol extract exhibited twice higher tyrosinase inhibitory activity than arbutin, whereas least inhibitory activity was seen in 20% ethanol extract. Conclusion : In this study, a attempt was made to investigate the tyrosinase inhibitory activity of Sasa quelpaertensis Nakai leaves extracted by different solvent condition. In the results, each extracts was prior to arbutin. Yet, 20% ethanol extract was lowest, but on the one hand, 60% ethanol extract demonstrated the highest tyrosinase inhibitory activity.

The global rice reduction due to drought averages 18 Mt, especially, 23 Mha of rice fields in Asia are drought-prone. However, rice breeding programs focusing on drought resistance have made little progress to date. Because proper screening approaches with large scale were not developed to evaluate the drought tolerant degree. In here, we have developed of leaf water loss rate with plastic ware in dark conditions for large screening. Through this bioassay system, we examined drought phenotype degrees of 650 rice varieties. To validate whether this optimized bioassay system is corelated with drought phenotype, we chose 14 varieties having the lowest or highest of the water loss rate. We observed the visual drought phenotype and agricultural traits in green house and field conditions. Apo and Samgang having the lowest of leaf water loss rate showed drought tolerance phenotype, whereas Yeolbaeg and Milyang254 having the highest of leaf water loss rate showed drought sensitive phenotype. Apo displayed proper root length trait and Samgang showed good root dry trait in the greenhouse conditions. These results suggest that a simple screening procedure with water lose rate of leaves is effective to perform large scale screening for drought phenotype in rice.

백련 잎의 소비확대를 위한 기초자료 확보측면에서 2007년 8월에 ‘가람’, ‘초의’, ‘백화건련’, ‘승달’ 백련의 잎을 수확하여 열수와 에탄올 추출물의 생리활성 효과를 조사하였다. 총 페놀함량은 열수 추출물의 경우 ‘초의’ 백련에서 78.3㎍·mL-1로 가장 많았고, 에탄올 추출물은 ‘백화건련’에서 146.8㎍·mL-1로 가장 많았다. 전자공여능은 추출물의 농도가 2,000ppm일 때 ‘승달’의 열수 추출물 및 에탄올 추출물에서 각각 83.3%와 94.0%로 가장 높았다. 총 플라보노이드 함량은 에탄올 추출물에서 높게 나타나 63.6㎍·mL-1(‘승달’)-92.2㎍·mL-1(‘초의’)를 나타낸 반면에 열수 추출물은 28.8㎍·mL-1(‘초의’) 이하를 나타내었다. 아질산염 소거는 추출물의 농도가 2,000ppm일 때 열수 추출물은 ‘초의’ 에서 69.2%로 가장 높게 나타났으며, 에탄올 추출물에서는 ‘백화건련’에서 80.7%로 가장 높게 나타났다. Tyrosinase 활성 저해 효과는 백련의 종류 및 용매에 관계없이 거의 나타나지 않았다. 항균활성은 에탄올 추출물에서 다소 높게 나타났는데, 저해환의 직경은 전반적으로 8.3-11.2mm를 나타냈다.