Composition of alkaloids in seeds of Lupinus mexicanus (Fabaceae) and antifungal evaluation of the alkaloid extract.

Capillary gas chromatography-mass spectrometry (CG-MS) was used to analyze the composition of alkaloids in seeds of Lupinus mexicanus . In addition, an in vitro study was made of the antifungal activity of the crude extract of alkaloids. The antifungal action of the extract was evaluated based on the inhibition of the mycelial growth of the phytopathogenic fungi Sclerotium rolfsii , Rhizoctonia solani and Fusarium oxysporum . The analysis of alkaloids from the extract revealed the presence of lupanine and 3 �-hydroxylupanine, multiflorine, aphylline, epiaphylline and �-isolupanine as majority compounds. The extract at the concentration of 3 mg mL -1 significantly inhibited the mycelial growth of R. solani by 87.7%, whereas the mycelial growth of S. rolfsii was only inhibited by 72.5% with the highest concentration lupanine was the most abundant alkaloid (76.2%) in the extract of seeds of L. mexicanus .