A biosynthetic intermediate of phytoalexins in banana fruits

Phytoalexins of Musa balbisiana [BBB] cv Saba sa Hapon and cv Mundo fruits were compared with those of M. acuminata [AAA] cv Bungulan fruits. Phytoale xins induced by wound and inoculation of Colletotrichum musae in these two cultivars were the same as those of Bungulan. In the course of analysis of the phytoalexins, 2-phenyl-1,8-naphthalic anhydride, 2-(4'-methoxyphenyl)- 1,8-naphthalic anhydride, and 1,2,3,4-tetrahydro-6,7-dihydroxy-1-(4'-hydrox ycinnamyliden)naphthalen-2-one were found as new phytoalexins of banana fru its. This latter compound is probably a biosynthetic intermediate of phenyl ; phenalenones in banana fruits. (C) 1998 Elsevier Science Ltd. All rights reserved.