Effect of Ultraviolet irradiation on the stilbenoid content of blueberry leaves

摘要

The stilbenoid content in various parts of blueberry plants and the effect of ultraviolet (UV) treatment on the stilbenoid content in blueberry leaves were investigated. Stilbenoid content was determined by HPLC analysis; the results showed significant differences in various parts of the plant. The leaves had the highest content oft-resveratrol andt-pinosylvin, 2.43 and 0.09 mu g/g dry weight, respectively. The leaves and pericarp had higher amounts oft-pterostilbene than the stem, and their values were 0.11 and 0.14 mu g/g dry weight, respectively. In order to enrich the stilbenoid content in the leaves, UV irradiation was performed on freshly collected leaves. After UV irradiation, the content oft-resveratrol andt-pterostilbene were significantly enriched; 3.1 and 1.5 times by UV-A, and 1.2 and 1.5 times by UV-C, respectively. Consequently, leaves treated with UV-A or UV-C may potentially be utilized as a good source of health-functional materials. Practical applications Despite the various functionalities and applications of stilbenoids, high costs are involved in its commercial production, due to its low content in blueberries. The results of this study can highlight strategies for cost reduction during processing. UV treatment is a simple method of physical processing, which may be used without causing contamination of the product.