Abstract
Rubiadin, a major compound of noni ($Morinda$ $citrifolia$) adventitious root, is highly valued in pharmaceutical industry due to hepatoprotective activity. To dissect rubiadin's effective extraction condition, extraction process of noni adventitious roots was performed with different solvent types, ratio of water to methanol (water, 20, 40, 60, 80, and 100% of methanol), extraction time, and extraction method. In contrast, we also developed a reverse- phase HPLC assay method to determine rubiadin from noni adventitious roots. The HPLC assay of rubiadin was performed by C-18 column using a gradient solvent system of methanol and water with UV detector at 280 nm. The extraction efficiency of different types of solvents were increased in order of methanol (0.08%) > ethanol (0.05%) > acetonitrile (0.03%) > acetone (0.02%) and methylene chloride (0.02%). The results of rubiadin extraction using different solvents showed that 1 hour of ultrasonic extraction was effective in order of 60% methanol (0.21%) > 80% methanol (0.13%) > 100% methanol (0.07%), 40% methanol (0.07%) and 2 hours of reflux extraction was effective in order of 60% methanol (0.21%) > 40% methanol (0.17%) > 80% methanol (0.14%). To compare the extraction efficiency of rubiadin according to the extraction methods and time for high rubiadin content, the extracts of rubiadin in noni adventitious roots were isolated with the methods of ultrasonic extraction, shaking extraction and reflux extraction. Rubiadin extracted from the methods of ultrasonic waves and shaking displayed the highest contents at 8 and 24 hours, respectively.
노니($Morinda$ $citrifolia$) 부정근의 주요 성분인 rubiadin은 간 보호 효과가 있어 제약산업에서 높은 가치가 있다. 노니 부정근의 주요 유효성분인 rubiadin의 효율적인 추출조건을 규명하고자 용매 종류, 물과 메탄올의 비율(물, 20%, 40%, 60%, 80%, 100%), 추출시간 및 추출방법을 달리하여 추출하였다. 노니 부정근에서의 rubiadin의 함량분석은 HPLC 이용 분석조건을 확립하였으며, C-18 컬럼을 사용하여 280nm에서 메탄올과 물로 농도구배를 주어 분석하였다. 용매별 추출효율은 메탄올(0.08%) > 에탄올(0.05%) > 아세토니트릴(0.03%) > 아세톤(0.02%) 및 메틸렌클로라이드(0.02%) 순으로 증가하였다. 메탄올에 물의 혼합 비율을 달리하여 초음파 추출기로 1시간 동안 추출한 결과 60% 메탄올(0.21%) > 80% 메탄올(0.13%) > 100% 메탄올(0.07%) 및 40% 메탄올(0.07%) 순으로 효과적이었으며, 환류냉각 추출기로 2시간 동안 추출한 결과 60% 메탄올(0.21%) > 40% 메탄올(0.17%) > 80% 메탄올(0.14%) 용매처리구 순으로 효율이 좋았다. 추출방법 및 추출시간에 따른 rubiadin의 추출 효율을 비교하기 위해 환류냉각추출 및 초음파추출, 진탕추출법으로 추출하였다. 추출방법 및 추출시간에 따른 rubiadin의 추출효율은 초음파추출 및 진탕추출에서 각각 8 및 24시간 동안 추출했을 때 효율적이었다.