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The anti-fungal activity of two alkaloids isolated from bulbs of Zephyranthes citrina was observed against 10 fungi, viz, Aternaria solani, A. triticina, Curvularia lunata, C. maculuns, Cercospora malvacearum, Erysiphe sp., Fusarium udum, Helminthosporium pisi, H. speciferum and Ustilago cynodontis. Different concentrations (200, 400, 600, 800, 1000 µg/ml of alkaloids (A and B) were used. Spore germination was inhibited at 600, 800, 1000 µg/ml. B alkaloid was used against Erysiphe cichoracearum causing powdery mildew in balsam (Impatiens balsamina) in the field as pre- and post-inoculation treatments at 1000, 1500, 2000 µg/ml doses. The extract was effective in both pre- and post-inoculation treatments. Foliar application of this alkaloid resulted in inducing synthesis of phenolic acid in the leaves of balsam. Maximum phenolics were detected in the leaves treated with 1500 µg/ml in both pre- and post-inoculation treatments. The increase in the production of phenolics in treated leaves of balsam can be correlated with the induction of resistance in treated plants against powdery mildew. The significant efficacy of the alkaloid under field conditions opens the possibility of its use by farmers for also controlling other diseases. [ABSTRACT FROM AUTHOR]

Xylopyrine-C, a new 14-membered ring cyclopeptide alkaloid, has been isolated from the root bark of Zizyphus xylopyra together with a known alkaloid scutianine-C, and their structures were established by chemical and spectral evidences. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the bark of Zizyphus xylopyra resulted in the isolation of two new 14-membered ring cyclopeptide alkaloids, xylopyrine-G and xylopyrine H. Their structures have been established by chemical and spectral evidences.