Phytochemical analysis of biologically active compounds of Artemisia dubia Wall. Using spectrophotometric methods

Abstract

Energy crops are becoming more popular in today's world. Many of these plants are not examined well (because their only purpose is to obtain energy), but they can also accumulate many other valuable substances that can be used to improve the quality of life, for example, in the field of health improvement. One such plant is from the Artemisia tribe - Artemisia dubia Wall. [1]. The aim of this investigation was to identify biologically active compounds, such as phenolic acids and flavonoids of Artemisia. A. dubia was collected from three different experimental areas with fertilization type: Non-fertilized; fertilized with N90 fertilizer and N170 fertilizer during different period: July 8, August 18 and September 7 in year 2016. Collected raw material was air-dried in Lithuanian Research Centre for Agriculture and Forestry and ground to ca. 3-5 mm size fraction. The extracts were prepared using 0.5 g of dried raw material and 20 mL 75% methanol. Extracts were left in a shaker for 24 h, and filtered afterward using filtering paper. Modified spectrophotometric analysis methods were used: Folin-Ciocalteu reagent was used to determine the total amount of phenolic compounds and AlCl3 method was used to determine flavonoids [2]. The results showed that the biggest content of phenolic compounds in rutin equivalents (RE) 81.52 mg/g including flavonoids 22.86 mg/g were determined in extracts of the plant collected in July in an experimental area with no fertilizers. The lowest content of bioactive compounds was determined in the extract of the plant, collected in September in an experimental area with N90 fertilizer. Spectrophotometric analysis showed that total amount of phenolic compounds and the total amount of flavonoids were not affected by fertilization of the plant but showed considerable differences between periods of a collection of the plant material.