棲狀褐茸藻Hincksia mitchellae(Harvey) P. C. Silva 天然物提純與結構解析

Abstract

在生物活性篩檢的實驗中，得知棲狀褐茸藻Hincksia mitchellae(Harvey) Silva之粗萃物具有抗病毒及抗凝血的活性，其中最明顯的藻褐素成分，具有抑制前列腺癌及髓性白血病進入細胞凋亡的活性，也因此期待能從棲狀褐茸藻的培養中得到更多的活性化合物。本研究自二氯甲烷層分離出5個化合物，分別為fucoxanthin (1)、apo-9’-fucoxanthinone (2)、grasshopper ketone (3)、apo-13’-fucoxanthinone (4)、apo-13’-fucoxanthinol (5)，自正己烷層分離出7個化合物，分別為trans-phytol (6)、linoleic acid (7)、 phytyl lenoleate (8)、phytyl 9-octadecenoate (9)、phytyl hexadecanoate (10)、α-tocopheryl quinine (11)、fucosterol (12)，以及自正丁醇層分離出3個化合物，分別為adenosine (13)、 tryptophane (14)、uridine (15)，其中化合物5為新的化合物。本研究為第一篇相關棲狀褐茸藻天然物的研究報告，這些源自棲狀褐茸藻的的藻褐素及其代謝物，在文獻上曾有抗腫瘤的活性，phytyl ester類化合物具有抗潰瘍的活性，α-tocopheryl quinone具有抑制白血癌細胞株P-388及直腸癌細胞株HT-29的活性，而fucosterol對於P-388有抑制作用，但在本研究中 並未測試相關活性。

Crude extracts of Hincksia mitchellae (Harvey) Silva has been found to exhibit significant anticlotting activity and antiviral activity in our previous screening task. The major pigment in the extract, fucoxanthin was reported to exhibit anticancer activity against human prostate and leukemia cancer. Here we investigated the chemical constituents of H. mitchellae for their structures and possible activities. Components of fucoxanthin (1), and its derivatives, apo-9’-fucoxanthinone (2), grasshopper ketone (3), apo-13’-fucoxanthinone (4), apo-13’-fucoxanthinol (5), and trans-phytol (6), linoleic acid (7), phytyl acylesters, phytyl lenoleate (8), phytyl 9-octadecenoate (9), phytyl hexadecanoate (10), α-tocopherylquinone (11), fucosterol (12), adenosine (13), tryptophane (14), and uridine (15) were isolated and structure determined on the basis of spectroscopic analysis and their correlation with the published spectroscopic data. Among them, compound (5) was a new compound ever published in the papers. This is the first paper of natural products from Hincksia mitchellae. Some of the isolated components are known to be bioactive, such as fucoxanthin and its derivatives in anticarcinoma activities, phytyl esters in antiulcer activity, α-tocopherylquinone in cytotoxicity against P-388 and HT-29 cell and fucosterol in cytotoxicity against P-388. However, none of the isolated components was tested for their bioactivities.