菱果石櫟與後大埔石櫟化學成分與生物活性之研究

Chemical Constituents and Bioactivities from the Leaves and Twigs of Lithocarpus synbalanos and L. corneus

王至欣(Chih-Hsin Wang)

指導教授 ： 張芳榮

高雄醫學大學/藥學院/天然藥物研究所碩士班/碩士(2016年)

摘要

殼斗科(Fagaceae)石櫟屬(Lithocarpus)主要分布在東亞，全世界約有一千種，在台灣被發現有15種。石櫟屬植物是常綠性喬木，主要生長在台灣的中部山區。過去文獻中，曾有降血壓、細胞毒殺、抗發炎、抗乳癌和抗糖尿病的活性相關研究。而在化學成分研究方面，主要有三萜類、固醇類、查耳酮類和酚性類的化合物曾經被分離過。本實驗經由活性篩選台灣產的石櫟屬植物，發現菱果石櫟和後大埔石櫟的甲醇萃取物具有抗發炎的活性。根據此活性數據，對這兩種植物有活性的部分進行後續的分離與研究。
經一系列管柱層析分離得到四個新化合物(1‒4)、三個首次從天然物中分離之化合物(5‒7)以及十四個已知化合物。其中化合物1為A環開環的降三萜，化合物2‒4為lupane類三萜。在生物活性方面，3-epi-betulinic acid (8)、cylicodiscic acid (16)和alphitolic acid (18)具有抑制人類免疫缺陷病毒活性，其IC50值分別為 4.5 ± 0.5 μM、6.2 ± 1.3 μM和6.7 ± 1.1 μM。而抗超氧化酶活性中，尤以3,4-seco-4(23),20(29)-lupadiene-3,28-dioic acid (5)為最佳，其IC50值為0.39 ± 0.10 μM。

關鍵字

菱果石櫟 ； 後大埔石櫟 ； 抗發炎活性 ； 抗人類免疫缺陷病毒活性

並列摘要

The genus Lithocarpus (Fagaceae) distributing in East Asia comprises more than 1000 species, and among them, 15 species were found in Taiwan. Lithocarpus plant is an evergreen arbor that grows in central mountainous area of Taiwan. In previous pharmacological studies, Lithocarpus plants were reported to have anti-hypertensive, cytotoxic, anti-inflammatory, anti-breast cancer, and anti- hyperglycemic activities. As results of earlier natural product researches, triterpenes, steroids, chalcones, and various phenolic compounds were considered as the major constituents of Lithocarpus plants. In our preliminary bioactive screening of Taiwanese Lithocarpus plants, the methanolic extract of L. synbalanos and L. corneus showed potent anti-inflammatory activity. Due to the bioactivity data and this uninvestigated plant material for its natural product chemistry, phytochemical investigation of the leaves and twigs of this species was carried out.
Repeated column chromatography of the extract of L. synbalanos resulted in the isolation of four new triterpenes (1−4), three compounds (5−7) isolated from nature product for the first time, and fourteen known compounds. Compound 1 is a A-seco-nor-triterpenoid and compounds 2‒4 are lupane-type triterpenoids. The anti-inflammatory and anti-HIV activities of the isolated natural products were evaluated. Among them, 3-epi-betulinic acid (8), cylicodiscic acid (11), and alphitolic acid (18) showed significant anti-HIV activity with an IC50 value of 4.5 ± 0.5 μM, 6.2 ± 1.3 μM and 6.7 ± 1.1 μM, respectively. 3,4-Seco-4(23),20(29)-lupadiene-3,28-dioic acid (5) exhibited potent inhibition of superoxide-anion generation with an IC50 value of 0.39 ± 0.10 μM.

並列關鍵字

Lithocarpus synbalanos ； Lithocarpus corenus ； anti-inflammatory ； anti-HIV

參考文獻

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