950 g of fresh bulb tissues of Urginea altissima were extracted with MeOH. The extract showed considerable antimicrobial activity against Phytophthora capsici, which was located in the water-soluble part. Chromatography over alumina yielded lycorine as an active component. Lycorine exhibited protective activity against blight (Phytophthora capsici) of tomato plants when an aqueous solution (500 µg/ml) was sprayed on the leaves. Its HCl salt had a slight enhancement in activity, while diacetyllycorine, dihydrolycorine and 2-acetyllycorine possessed lower activity than lycorine itself. The CHCl3 soluble part of the MeOH extract, chromatographed over Si gel and TLC, gave the alkaloid acetylcaranine (2). (2) was identical with an authentic specimen derived from caranine by acetylation (mmp, IR, NMR), and this is the first report of (2) as a natural product.