Department of Pharmacognosy, Anadolu University, Faculty of Pharmacy, 26470 Eskisehir, Turkey.
Acta Trop. 2013 Dec;128(3):557-60. doi: 10.1016/j.actatropica.2013.08.003. Epub 2013 Aug 12.
Date palm, Phoenix dactylifera L. (Arecaceae), grows commonly in the Arabian Peninsula and is traditionally used to treat various diseases. The aim of the present study was to identify chemical composition of the essential oil and to investigate the repellent activity. The essential oil of P. dactylifera was obtained by hydrodistillation from the spathe, a specialized leaf structure that surrounds the pollinating organs of the palm. The oil was subsequently analyzed by GC-FID and GC-MS. The oil showed promising repellent activity against yellow fever mosquito - Aedes aegypti. Sixteen components were characterized, constituting 99% of the oil. The main components were 3,4-dimethoxytoluene (73.5%), 2,4-dimethoxytoluene (9.5%), β-caryophyllene (5.5%), p-cresyl methyl ether (3.8%), and caryophyllene oxide (2.4%). The minimum effective dosage (MED) for repellency for the P. dactylifera oil was 0.051mg/cm(2), which had moderately lower potency compared to reference standard N,N-diethyl-3-methylbenzamide, DEET (0.018mg/cm(2)) in the "cloth patch assay". The five major compounds were individually assayed for repellency to determine to what extent each is responsible for repellency from the oil. 3,4-Dimethoxytoluene and 2,4-dimethoxytoluene showed the best repellent activity with the same MED value of 0.063mg/cm(2), respectively. The results indicate that these two constituents which comprise a large proportion of the P. dactylifera oil (83%) are likely responsible for the observed repellent activity. In this aspect, the P. dactylifera spathe oil is a sustainable, promising new source of natural repellents.
海枣，凤凰木（棕榈科），生长在阿拉伯半岛常见，并被传统上用于治疗各种疾病。本研究的目的是确定的化学成分和研究的驱虫活性。海枣的精油是通过水蒸馏从叶鞘，一个专门的叶结构，围绕着授粉器官的棕榈。油随后通过 GC-FID 和 GC-MS 分析。该油对黄热病蚊子 - 埃及伊蚊表现出有希望的驱避活性。鉴定了 16 个成分，占油的 99％。主要成分是 3,4-二甲氧基甲苯（73.5％），2,4-二甲氧基甲苯（9.5％），β-石竹烯（5.5％），对甲酚甲基醚（3.8％）和石竹烯氧化物（2.4％）。驱避效果的最低有效剂量（MED）为 0.051mg/cm（2），与参考标准 N，N-二乙基-3-甲基苯甲酰胺相比，DEET（0.018mg/cm（2））在“布片试验”中具有较低的效力。单独测试了五种主要化合物的驱避活性，以确定每种化合物对油的驱避活性的贡献程度。3,4-二甲氧基甲苯和 2,4-二甲氧基甲苯表现出最好的驱避活性，具有相同的 MED 值 0.063mg/cm（2）。结果表明，这两种组成部分占海枣油的很大比例（83％），可能是导致观察到的驱避活性的原因。在这方面，海枣叶鞘油是一种可持续的、有前途的天然驱避剂新来源。
