Saudi folk medicine: phytochemical and antimicrobial screening.

Plants of 25 families, encompassing 30 species were selected on the basis of their folklore uses and literature data for the present screening. Besides phytochemical screening the plant extracts were prepared and tested for their antimicrobial activity. The result of the testing showed that about 77% of these plants exhibited some level of antibacterial activity. The most common chemical constituents found in these plants were sterols and/or triterpenes, falvonoids, alkaloids and tannins. Volatile oils, volatile bases, saponins, coumarins, anthraquinones and cardiac glycosides were also detected.