Institute of Applied Research, Galilee Society (Affiliated with University of Haifa), P.O. Box 437, Shefa-Amr 20200, Israel.
Vet Parasitol. 2013 Jan 16;191(1-2):44-50. doi: 10.1016/j.vetpar.2012.08.016. Epub 2012 Aug 28.
The infection of grazing ruminants with gastro-intestinal nematodes (GINs) is a severe problem in the Middle East. However, goats that graze the south-western slopes of the Carmel Heights in Israel have very low faecal egg counts, despite high grazing density. We hypothesized that polyphenols from Pistacia lentiscus L. and/or Phillyrea latifolia L. - both prevalent woody species of the region that are consumed by goats - have anthelmintic bioactivity. We tested this hypothesis by using the larval exsheathment inhibition assay (LEIA). Extracts were prepared from leaves of either plant species using 70% ethanol (E70), 100% ethanol (E100), or boiling water (W). Larvae were incubated in a phosphate-buffered saline solution with or without plant extract (1200μg/ml) and then exposed to an exsheathment solution expected to elicit 100% exsheathment after one hour. All extraction methods of P. lentiscus were highly effective at inhibiting larval exsheathment, but higher potency was found for the E70 than for E100 extraction method, while W was intermediate. Only the E70 extract of P. latifolia was highly effective relative to the control. The E70 extract of P. lentiscus had more than 7 times the potency of the E70 extract of P. latifolia. Irrespective of solvent and tannin-equivalent used, P. lentiscus contained more than double the quantity of total polyphenols than P. latifolia. The polyphenols of P. lentiscus consisted mainly of galloyl derivatives (63.6%), flavonol glucosides (28.6%), and catechin (7.8%). In P. latifolia, oleuropein and its derivative tyrosol accounted for 49.3 and 23.1% of phenolics, respectively, the remainder being flavones (luteolin and quercetin) and their glucoside derivatives. Results of the LEIA test suggest that extracts of tannin-rich plants interfere with the very early stage of host invasion and that high concentration of galloylated derivatives may explain anthelmintic activity.
中东地区反刍动物胃肠道线虫（GIN）感染是一个严重的问题。然而，在以色列 Carmel Heights 西南坡放牧的山羊，尽管放牧密度很高，但粪便中的虫卵计数却非常低。我们假设从该地区普遍存在的木本植物黄连木（Pistacia lentiscus L.）和/或滨藜（Phillyrea latifolia L.）的叶子中提取的多酚具有驱虫的生物活性。我们通过幼虫蜕皮抑制试验（LEIA）来检验这一假设。使用 70%乙醇（E70）、100%乙醇（E100）或沸水（W）从这两种植物的叶子中制备提取物。将幼虫在含有或不含有植物提取物（1200μg/ml）的磷酸盐缓冲盐溶液中孵育，然后暴露于预计一小时后 100%蜕皮的蜕皮溶液中。黄连木的所有提取方法均能高度有效地抑制幼虫蜕皮，但 E70 提取法比 E100 提取法效果更好，而 W 则介于两者之间。只有 P. latifolia 的 E70 提取物相对于对照具有高度的有效性。黄连木的 E70 提取物的效力比 P. latifolia 的 E70 提取物高出 7 倍以上。无论使用哪种溶剂和单宁当量，黄连木的总多酚含量均是滨藜的两倍以上。黄连木的多酚主要由没食子酰衍生物（63.6%）、黄酮醇葡萄糖苷（28.6%）和儿茶素（7.8%）组成。在滨藜中，橄榄苦苷及其衍生物酪醇分别占酚类化合物的 49.3%和 23.1%，其余为黄酮类（木樨草素和槲皮素）及其糖苷衍生物。LEIA 试验的结果表明，富含单宁的植物提取物干扰宿主入侵的早期阶段，而高浓度的没食子酰衍生物可能解释了驱虫活性。
