Analysis of thuja (Thuja spp.) biological activity

Abstract

The object of investigation of this research were leaves and bark of Thuja standishii (Gord.) Carr., Thuja occidentalis L. and Thuja occidentalis ‘Aurescens’. The aim was to measure quantities of flavonoids and phenolic compounds, radical scavenging activities, compare the results to find out which parts of the plant and which species produce the most of the compounds, evaluate the effects of storage allelopathic and antimicrobial properties. Gas chromatography-mass spectroscopy revealed that the main compounds in T. occidentalis leaves and bark are α-thujone, fenchone and β-thujone, in the wood – sabinene, α-thujone and terpin-1-en-4-yl acetate, in the cones – α-fenchene, α-thujone and myrcene. The main compounds in T. occidentalis ’Aurescens‘ leaves are limonene, delta-3-carene and α-pinene, in the bark – caryophyllene and humulene, in the wood – sabinene, terpin-1-en-4-yl acetate and caryophyllene, in the cones – α-pinene and delta-3-carene. The main components in the extract of T. standishii leaves are sabinene and α-pinene, in the essential oil of the leaves – terpinen-4-ol, sabinene and β-selinene, in the distillate of the leaves – terpinen-4-ol and α-terpinol, in the bark and cones – sabinene, α-pinene and myrcene. All of the T. occidentalis extracts had some allelopathic properties against Lepidium sativum L. Vegetation period had little effect on the allelopathic properties. The extracts of T. occidentalis leaves inhibits the growth of L. sativum more than the extracts of cones and bark (including viability, the length of the stem and of the root). Nevertheless, in some cases the extracts made of cones have shown higher effect comparing to the extracts of leaves. Antifungal activity was measured against Penicillium candidum and Penicillium roqueforti. None of the extracts had any inhibition in the growth of these fungi. However, the essential oils had some effect [...]