Alkaloid content and essential oil composition of Mahonia breviracema cultivated under different light environments

Abstract

Light can affect the yields of alkaloid and essential oil in the synthesis of secondary metabolites directly or indirectly through plant growth. Despite Mahonia breviracema being an endemic medicinal species in China, research on the influence of light on production of alkaloid and essential oil is scarce. Thus, this research evaluated the influence of various lighting conditions on alkaloid yields and the composition and yields of the essential oils of M. breviracema. The results revealed significant differences in alkaloid yields, oil yieldsand chemical characteristics of M. breviracema grown in four different light intensities from 10 to 100% full sun shine. The total amount of alkaloids in plants under I30 and I50 was higher than that under I10 and I100 due to the higher biomass of plants. Oil yield of M. breviracema leaf increased linearly with the increase of lightincidence. Plants grown under I10 had less plastoglobuli, which coincided with the lowest oil yield (1.91 g kg-1). The plastoglobuli in chloroplasts increased when the irradiance levels increased, resulting in the highest oil yields under I100 (4.53 g kg-1). The principal components in the leaves of M. breviracema were hexadecanoic acid (10.54-72.19%) and α-ionone (1.25-42.39%). The highest hexadecanoic acid content was obtained under I50, followed by I30, and the highest α-ionone content was obtained under I100. Therefore, it is necessary to control the light environment to obtain raw materials with high quality.