School of Science, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia.
Tropical Medicine and Biology, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia.
J Appl Microbiol. 2019 Jul;127(1):59-67. doi: 10.1111/jam.14287. Epub 2019 May 21.
The aim of this study was to investigate the antimicrobial activities of Etlingera pubescens, and to isolate and identify the antimicrobial compound.
The crude extracts of E. pubescens were obtained through methanol extraction, and evaluated for antimicrobial activities. From this extract, 1,7-bis(3,4-dihydroxyphenyl)heptan-3-yl acetate (etlingerin) was isolated. When compared to curcumin (a compound with a similar chemical structure), etlingerin showed twofold lower minimum inhibitory concentration values while also being bactericidal. Through time kill assay, etlingerin showed rapid killing effects (as fast as 60 min) against the Gram-positive bacteria (Staphylococcus aureus ATCC 43300 and Bacillus subtilis ATCC 8188). Further assessment revealed that etlingerin caused leakage of intracellular materials, therefore suggesting alteration in membrane permeability as its antimicrobial mechanism. Cytotoxicity study demonstrated that etlingerin exhibited approximately 5- to 12-fold higher IC values against several cell lines, as compared to curcumin.
Etlingerin isolated from E. pubescens showed better antibacterial and cytotoxic activities when compared to curcumin. Etlingerin could be safe for human use, though further cytotoxicity study using animal models is needed.
Etlingerin has a potential to be used in treating bacterial infections due to its good antimicrobial activity, while having potentially low cytotoxicity.
本研究旨在探讨地菍的抗菌活性，并分离和鉴定其抗菌活性成分。
采用甲醇提取法提取地菍粗提物，并对其抗菌活性进行评价。从该提取物中分离得到 1,7-双(3,4-二羟基苯基)庚烷-3-基乙酸酯（地菍素）。与化学结构相似的姜黄素相比，地菍素的最低抑菌浓度值低两倍，但具有杀菌作用。通过时间杀伤试验，地菍素对革兰氏阳性菌（金黄色葡萄球菌 ATCC 43300 和枯草芽孢杆菌 ATCC 8188）表现出快速杀伤作用（最快 60 分钟）。进一步评估表明，地菍素导致细胞内物质泄漏，因此表明其抗菌机制是改变膜通透性。细胞毒性研究表明，与姜黄素相比，地菍素对几种细胞系的 IC 值高 5-12 倍。
与姜黄素相比，从地菍中分离得到的地菍素具有更好的抗菌和细胞毒性活性。地菍素可能对人类安全，但需要进一步使用动物模型进行细胞毒性研究。
由于地菍素具有良好的抗菌活性，同时可能具有较低的细胞毒性，因此它有可能用于治疗细菌感染。
