DARK-INDUCED CHANGES IN THE CONTENT OF PHENOLIC-ACIDS IN CALLUS-CULTURE OF ALFALFA (MEDICAGO-SATIVA)

The changes in the content of free and esterified phenolic acids extracted with methanol and the phenolic acids nonextractable with this solvent were studied during a long term cultivation (4 subcultures, 27 weeks total) of alfalfa callus in darkness and light. The total content of phenolic acids in the callus grown in darkness was lower as compared to their content in callus cultivated under 10/14 h light/darkness regime. It was decreasing during cultivation differently in the two treatments being in light-grown callus dependent on the length of cultivation and decreasing by each subcultivation in darkness. The portion of benzoic acid derivatives related to the total phenolic acids changed with the age of the culture reaching 90 % after the fourth subcultivation in darkness while only 45 % in light. Considerable decrease of the content of esterified form of phenolic acids accompanied by relatively stable content of free and firmly bound phenolic acids caused significant decrease of esters as related to total phenolic acids (from 87 % to 25 %). © 1990 Kluwer Academic Publishers.