Abstract
Centella asiatica is one of the local herbs that is claimed to possess various physiological effects. C. asiatica also accumulates large amounts of pentacyclic triterpenoid saponins known as centelloids. These terpenoids usually include asiatic acid, asiaticoside, madecassoside, and madecassic acids. In the present study, to understand the changes of triterpene glycoside levels in the different shoot tissues of C. asiatica during seasonal cultivation, we investigated the High-Performance Liquid Chromatography (HPLC) analysis via different extraction methods, such as water, 20% ethanol and methanol extracts. Significant increases were observed in the levels of madecassoside and asiaticoside in the leaf extracts by methanol compare with extracts using water or 20% ethanol. Additionally, we also analyzed the various antioxidant activity in the different shoot tissues of C. asiatica using different extracts, such as leaves, petioles and both materials. Among these petiole extracts showed high 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTs) scavenging activity in all extracts, whereas 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity exhibited high activity levels in the leaf part using methanol and ethanol extracts. Levels of total phenolics and flavonoid also showed the highest levels in the leaf tissues using all extracts such as methanol, ethanol and water. Our results indicated that the increased levels of triterpene glycoside and antioxidant activity in the leaf parts of the C. asiatica were indicating that useful metabolites were mainly maintained through seasonal cultivation such as madecassoside, asiaticoside.
본 연구에서는 약용식물인 병풀의 계절적 생육조건의 변화에 따른 다양한 지상부 조직에서 triterpene glycoside 함량을 조사하기 위해, 20% 에탄올, 메탄올, 물을 이용한 3가지 추출방법을 이용하여 HPLC 분석을 수행하였다. 메탄올 추출방법에서 triterpene glycoside의 추출효율이 가장 높았으며, 특히 madecassoside와 asiaticoside의 값이 계절적인 생육조건의 변화동안 높게 확인되었다. 본 연구에서는 추가적으로 항산화활성을 분석하였으며, ABTs 소거활성은 잎자루에서 높게 확인되었으며, DPPH 소거활성은 메탄올과 에탄올로 추출한 잎조직에서만 높은 결과를 보였다. 총 페놀 및 플라보노이드 함량은 잎 조직에서 사용된 물, 에탄올, 메탄올 추출에 의한 결과가 가장 높은 값을 보였다. 본 연구의 결과로서, 병풀 식물체의 잎 조직에서 계절적 생육 조건 동안 triterpene glycoside 및 항산화활성이 증가함은 병풀의 재배시 madecassoside 및 asiaticoside를 포함한 유용한 주요 대사물질들이 식물체내에서 항상성을 위해 유지되며, 이는 향후 보 다 구체적인 생리활성에 대한 연구가 필요할 것으로 생각되는 바이다.
