Accumulation of hydroxybenzoic acids and other biologically active phenolic acids in shoot and callus cultures of Aronia melanocarpa (Michx.) Elliott (black chokeberry)

Phenolic acids are plant metabolites important in phytotherapy and also in cosmetology. In this study, proliferating shoot and callus cultures of Aronia melanocarpa were established and maintained on Linsmaier and Skoog (L-S) medium containing different levels of alpha-naphthaleneacetic acid (NAA) and 6-benzyladenine (BA), ranging from 0.1 to 3.0 mg l(-1). Methanolic extracts from the biomass of these cultures and from the fruits of soil-grown plants were used to determine the amounts of free phenolic acids and cinnamic acid using the high-performance liquid chromatography (HPLC) method. Out of a total of twelve analyzed compounds, all of the extracts contained four of them: caffeic acid, p-hydroxybenzoic acid, syringic acid, and vanillic acid. Moreover, shoot extracts also contained salicylic acid (o-hydroxybenzoic acid), while callus extracts contained p-coumaric acid. On the other hand, fruit extracts also contained both salicylic acid and p-coumaric acid. The total amount of the analyzed compounds in extracts from both shoot and callus cultures depended on the L-S medium used, and varied between 103.05 and 150.95 mg 100 g(-1) dry weight (DW), and between 50.23 and 81.56 mg 100 g(-1) DW, respectively. Both types of culture contained higher levels of phenolic acids than the fruit extracts (32.43 mg 100 g(-1) DW). In shoot cultures, p-hydroxybenzoic acid and salicylic acid were the predominant metabolites (reaching 55.14 and 78.25 mg 100 g(-1) DW, respectively), while in callus cultures, p-hydroxybenzoic acid (25.60 mg 100 g(-1) DW) and syringic acid (41.20 mg 100 g(-1) DW) were the main compounds. In fruit extracts, salicylic acid (15.60 mg 100 g(-1) DW) and p-hydroxybenzoic acid (5.29 mg 100 g(-1) DW) were predominant.