TOXIC AND ANTIFUNGAL PROPERTIES OF THE ESSENTIAL OILS OF <em>CINNAMOMUM</em> SPECIES FROM PENINSULAR MALAYSIA

Abstract

The essential oils of seven Cinnamomum species from Peninsular Malaysia (C. pubescens, C.javanicum, C. iners, C. impressicostatum, C. mollissimum, C. porrectum and C. camphora) were investigated for their toxic and antifungal properties. Brine shrimp lethality bioassay on the essential oils revealed that samples distilled from the leaf of C. mollissimum, C. iners and C. impressicostatum were very toxic to the brine shrimp with a LC₅₀ of 1.6, 5.1 and 11.6 ug ml^-1 respectively. The essential oils from the other species also showed high toxicity values with LC₅₀ mostly < 100 ug ml^-1. The inhibitory study of the essential oils on the growth of three fungi species, viz. Gloeophyllum trabeum, Coriolus versicolor and Bostryodiplodia theobromea by the agar dilution technique indicated that the essential oils were effective. The leaf oil of C. pubescens was the most effective, exhibiting ED₅₀ of 60.3 ug ml^-1 for C. versicolor, 58.8 ug ml^-1 for G. trabeum
and 48.0 ugml^-1 for B. theobromea. The bark oil of C. javanicum also exhibited significant inhibitory activity against the three fungi with ED₅₀ ranging from 84.4 to 324.0 ug ml^-1.