Antifungal Effects of Thai Medicinal Plants AgainstCollectotrichum gloeosporioides Penz.

摘要

This study was conducted to develop more efficient and environmentally sound methods for thecontrol of anthracnose. Twelve Thai medicinal plants were tested as potential anti-fungal agentsagainst Colletotrichum gloeosporioides Penz. Hexane and ethyl acetate extracts from the pericarpof Areca catechu and hexane extract from the flower buds of Etlingera elatior demonstrated highinhibitory activity of C. gloeosporioides mycelial growth with EC50 values of 796.2, 803.9 and 803.9mug mL-1, respectively. These extracts were fractionated and purified by column chromatography.Consequently, six compounds from the A. catechu high active extracts and two compounds fromthe E. elatior high active extract were isolated. Based on the results of structural elucidation, thesix compounds obtained from the A. catechu high active extracts were fernenol, arundoin, lauricacid, myristic acid, palmitic acid and a mixure of beta-sitosterol and stigmasterol. The two compoundsobtained from the E. elatior high active extract were lauric acid and a mixture of beta-sitosterol andstigmasterol. The effects of these compounds on spore germination, germtube elongation andappressorium formation were investigated; fernenol was found to provide the highest inhibitionin all aspects based on EC50 values of 45.8, 26.7 and 65.6 mug mL-1. Lauric acid, myristic acid andpalmitic acid with EC50 > 200 mug mL-1 had the least inhibitory activity. The results suggest thatthe compounds isolated from the pericarp of A. catechu and the flower buds of E. elatior may beapplicable for the control of anthracnose diseases.