Anthocyanin composition and antimicrobial activity of sour cherry (Prunus cerasus L.) fruit extracts

Accumulation and composition dynamics of anthocyanins and phenols in the fruit of sour cherry 'Lotine' were estimated during 2007-2009 at ripening stage. The effect of extracts made from sour cherry fruit of different ripeness on gram-positive and gram-negative bacteria and yeast was evaluated. It was established that the amount of anthocyanins steadily increased and the content of phenols decreased during cherry fruit ripening. The highest amount of anthocyanins (127 mg 100 g(-1)) was measured in the over-ripe fruit. Delphinidin-3-glucoside was the most abundant anthocyanin (53-55%) of the five identified in the sour cherry fruit extracts and its quantity varied inappreciably during ripening. The highest amount of phenols was established in fruit at the onset of ripening stage. Antimicrobial activity of the extracts made from anthocyanin - rich sour cherry 'Lotine' fruit at ripening and time of harvest stages were investigated using agar diffusion method. Staphylococcus aureus culture was found to be the most sensitive to the extracts tested. Cultures of gram-negative bacteria and yeast were weakly susceptible or resistant to the extracts tested.