The effect of feeding culture media with biogenetic precursors on high production of depsides in agitated shoot cultures of black and red aronias

Agitated shoot cultures of two aronias, Aronia melanocarpa (Michx.) Elliott and Aronia arbutifolia (L.) Pers., were maintained on Murashige & Skoog medium (1 mg/l BA and 1 mg/l NAA), both with and without the addition of various biosynthetic precursors of phenolic acids and depsides (phenylalanine, cinnamic acid, benzoic acid and caffeic acid). Each substance was added in 5 concentrations (0.1–10 mmol/l), each concentration at two time points (at the beginning and on the 10th day of cultures). Twenty-four phenolic acids were determined in methanolic extracts of the biomasses collected after 20 days of growth cycles by means of HPLC method with DAD detection. The presence of seven compounds was confirmed in all the extracts—five depsides (neochlorogenic, chlorogenic, cryptochlorogenic, isochlorogenic and rosmarinic acids), and syringic and caffeic acids. The main metabolites in A. melanocarpa shoot extracts were isochlorogenic, chlorogenic and neochlorogenic acids (max. 249.88, 450.35, 192.16 mg/100 g DW). The main metabolites in A. arbutifolia shoot extracts were: chlorogenic, isochlorogenic and cryptochlorogenic acids (max. 361.60, 224.5, 526.2 mg/100 g DW). The largest total amounts of the compounds were confirmed in the cultures of both aronias after the addition of cinnamic acid (989.79 and 661.77 mg/100 g DW, respectively) and caffeic acid (854.99 and 1098.46 mg/100 g DW, respectively) at concentrations of 5 mmol/l on 10th day of growth cycles. These maximum amounts were 3.41, 3.42, 2.95 and 5.67 times higher, respectively, than in the control cultures. This is the first report documenting the high production of depsides in shoot cultures of black and red aronias after feeding with their biosynthetic precursors.