This study was carried out on the aerial parts (leaves and stems) of each of the following plant species:-Salvia fruticosa, Ocimum basillicum and Pelargonium graveolans cultivated in AL-Jabal AL-Akhdar province. The results of the preliminary phytochemical screening of their aerial parts revealed the presence of volatile oil, carbohydrates and /or glycosides, flavonoides both aglycones and glycosides and tannins. This screening proved the absence of alkaloids, cardiac glycosides, saponines and anthraquinones aglycones and glycosides. The total percentages of carbohydrates in the three studied plants were determined spectro-photometrically ; the highest contents were found to be for Pelargonium 3.86% followed by Ocimum 1.79% and the lowest was for Salvia 1.4%. The percentages of total phenolic contents were determined using ferricyanid complex assay [spectro-photometric Prussian blue method]. The percentages of total lipids were determined. The total alcohol extracts of each plant species were subjected to some in vitro biological studies viz.:-antimicrobial activity against some gram positive , gram negative bacteria and certain fungal strains and exhibited a significant antimicrobial effect. Moreover, these examined alcohol extracts revealed both a marked anti-worm and inhibition effects against earth worm (Allolbophoa caliginosa) and garden slugs. Most organic and chemical slug control methods are generally ineffective. The chemical control methods are dangerous and poisonous to other beneficial mammals. Therefore, these extracts could be used as a natural anthelmintic and slug control agents.
