Background: The bark of Cinnamon (Cinnamomum zeylanicum Blume.) and rhizome of Ginger (Zingiber officinale Rosc.) have been widely used as spice in Iranian diets. Objective: The aim of the present study is the evaluation of cytotoxicity of the essential oil and various extracts of these two plants using Brine shrimp lethality assay (BSL). Methods: The plants were prepared from a local market and their scientific names were confirmed with microscopic analysis. The essential oils and various extracts in increasing polarity order were prepared with hydro distillation and percolation method respectively. The cytotoxicity of all fractions was evaluated using BSL method in 10, 100 and 1000 μg/ml concentrations. Results were analyzed using software of probit analysis. Results: Chloroform, essential oil and ether extracts of cinnamon with LC50 = 9, 10 and 18 μg/ml respectively ) and essential oil, petroleum ether, methanol and chloroform extracts of Ginger with LC 50 = 0.03, 4.03, 7.9 and 8.89 μg/ml exhibited the most cytotoxicity in comparing to potassium dichromate (LC50= 27.75 μg/ml). Conclusion: All of the fractions from the bark of Cinnamon and rhizome of Ginger exhibited high cytotoxicity. However it is needed more separation and identification of active components on the basis of this biological activity. If these results would confirm with the other bioassays, it is suggested to make safety recommendations for daily consumption of these two plants.

Background: Stachys acerosa Boiss (Lamiaecae) is an endemic plant of Iran. Objective: Because there is no report about this plant and according to medicinal uses of another species of Stachys, in this investigation, chemical composition and antimicrobial acivity of essential oils of flowering and non flowring tops of S. acerosa were studied and the component with antimicrobial activity was identified. Methods: Flowering and non flowering tops of the plant were collected from Lalehzar (Kerman provience) and after drying their essential oils were obtained by Clevenger apparatus. The oils were analyzed by GC-MS apparatus and retention indices. Antimicrobial activities of essential oils against Staphylococcus aureus, S. epidermidis, Eshrichia coli, Bacillus subtillis, Kelebsiella pneumonia and Pseudomonas aeroginosa were investigated by bioautography method on silica gel GF254 TLC plates developed in toluene: ethyl acetate (93:7). Results: Flowering and non flowering plants yielded 0.09% and 0.11% (v/w) of clear yellowish essential oil and chrysanthenyl acetate and linalool as were major constituents respectively. Most anitimicrobial activities, detected by TLC, showed in Rf=0.5-0.6 in essential oil of non flowering tops and after extraction of this fraction from preparative TLC and GC-MS analysis, it showed that Carvacrol was the major compound. Conclusion: There are reports about antimicrobial activities of other Stachys species, and chrysanthenyl acetate and linalool as major constituents of essential oils in other species of Stachyes.