The chemical composition of Microbiota decussata.

From the leaves of Microbiota decussata (Cupressaceae) biflavones: cupressuflavone, amentoflavone and 7-O-methylamentoflavone were isolated and identified. The amount of cupressuflavone in Microbiota decussata and xCupressocyparis leylandii (Leyland cypress) (Cupressaceae) was determined by HPLC (1.82% and 0.83%, respectively). The chemical composition of essential oils from bark and leaves of Microbiota decussata was established by GC-MS (GC-FID) analysis. As a major component thujopsene (39.2% and 45.9%, respectively) was identified. Wiridiflorol (3.0%) and tau-muurolol (0.3%) were present only in leaves but globulol (1.5%) exclusively in bark. The content of essential oils in M. decussata was high--5.4% in bark and 12.6% in leaves. The essential oils from M. decussata and xC. leylandii were bioassayed towards different fungi of the genus Fusarium. Leyland cypress essential oil at 2% concentration fully inhibited the growth of all fungi.