Utilization and Evaluation of Tropical Medicinal Resources

1. 泰国传统药物中种子分子的分离(1)葛根（Leguminosae）（泰名“Kwaw-keur”）被认为是老年人推荐的一种恢复活力的民间药物。对其活性原理进行了重新研究，分离得到两个新化合物：脱氧雌醇和异雌醇。脱氧雌雌醇的雌激素活性比已报道的最活性成分雌雌醇强10倍。有证据表明，微雌醇是脱氧微雌醇产生的人工产物。研究了该植物的异黄酮结构和雌激素活性。(2)对产自泰国北部的小蒙塔纳（Tabernaemontana corymbosa）的吲哚类生物碱进行了研究，分离得到6种吲哚类生物碱，分别为ervatamine、20-epiervatamine、voacangine、voacristine、tabernaemonatanine、dregamine。改善难溶性药物溶出度的研究(1)以水溶性物质为载体改善溶出度，将脱氧胆酸或氧氟沙星与水溶性载体混合形成固体分散体。选择PEG6000、尿素和甘露醇作为载体。采用粉末x射线衍射法、差示扫描量热法和红外光谱法对药物载体相互作用进行了精确研究。(2)以多孔材料为载体改善溶出，制备了水不溶性药物与受控孔玻璃的物理混合物。采用差示扫描量热法、压差扫描量热法、粉末x射线衍射法和红外光谱法研究了测试固体分散体的物理化学性质。

1. Isolation of seed molecules from Thai traditional medicines(1) Pueraria mirifica (Leguminosae) (Thai name "Kwaw-keur") is known as a rejuvenating folk medicine recommended to aged people. Reinvestigation for the active principle resulted in isolation of two new compounds, deoxymiroestrol and isomiroestrol. Deoxymiroestrol was found to possess 10 fold stronger estrogenic activity over miroestrol which had been reported to be most active principle of the plant. Evidence was obtained to suggest miroestrol is an artefact arising from deoxymiroestrol. Isoflavonoid of the plant was studied for the structures and estrogenic activity.(2) Indole alkaloids of Tabernaemontana corymbosa from northern Thailand was studied and six indole alkaloids, ervatamine, 20-epiervatamine, voacangine, voacristine, tabernaemonatanine, dregamine, were isolated.2. Studies on improved dissolution of poorly soluble drugs(1) Improved dissolution using water soluble substances as carriersUrsodeoxycholic acid or ofloxacin were mixed with water soluble carriers to form solid dispersions. PEG6000, urea, and mannitol were chosen as the carriers. Powder X-ray diffractometry, differential scanning calorimetry, and infrared spectroscopy were used to study drug-carrier interactions precisely.(2) Improved dissolution using porous materials as carriersThe physical mixtures of a water insoluble drug and controlled pore glass were prepared. Physicochemical properties of the test solid dispersions were studied by differential scanning calorimetry, pressure differential scanning calorimetry, powder X-ray diffractometry, and infrared spectrometry.