1Instituto de Ecología, UNAM. Ciudad Universitaria. AP 70-275. México 04510, México.
2Centro de Ciencias Mediambientales, CSIC. Serrano 115.dpdo., Madrid, 28006, Spain.
3Dept. of Botany & Plant Sciences. Riverside, CA 92521-0124, USA.
4Facultad de Química, UNAM. Ciudad Universitaria. México, 04510, México.
Callicarpa acuminata H. B. K. (Verbenaceae) is a common plant of secondary plant communities. It is distributed along the coast of Gulf of Mexico to the Yucatan Peninsula. The present study is the first bioassays-guided fractionation performed with this plant following the responses of Leptinotarsa decemlineata Say (potato beetle), Spodoptera littoralis Bois, Myzus persicae Sulz, and Artemia salina, to their organic extracts, chromatographic fractions, and the compounds H-9, its methylated derivative H-9 met, K44, and K45 that have been isolated from several bioactive fractions. Their chemical structures have been determined based on IR, MS, NMR H1, and NMR C13 analysis. Compound H9 and H9met (two abietane diterpenes) were isolated from a fraction with strong antifeedant effects against Colorado beetle, Leptinotarsa decemlineata. However, the individual effects of these compounds did not account for the bioactivity of the parent fraction. A synergistic effect probably gives more toxicity to the parent fraction. Compounds. K44 (alpha-amyrin) and K45 (a mixture) were isolated from a near active fraction with strong deterrence against L. decemlineata, being K45 responsible for such effect. K44 and K45 were also toxic when abdominally injected to this beetle, while H9 and H9met did not affect its survivorship. All of these compounds had significant shrimp lethality but such toxicity did not correlate with insect deterrence or toxicity.