Sulfated Triterpenes from Lemon Balm

The hydroalcoholic (EtOH/H2O) extract of matured leaf margins of lemon balm (Melissa officinalis L.) afforded a new 3,23-disulfate of 2 alpha,3 beta-23,29-tetrahydroxyolean-12-en-28-oic acid 28-O-beta-D-glucopyranoside (1) and a new 23-monosulfate of 2 alpha,23-dihydroxyurs-12-en-28-oic acid 3-O-beta-D-glucopyranoside (2), along with six known compounds, i.e., 23-monosulfate of 2 alpha,3 beta,19 alpha,23-tetrahydroxyurs-12-ene-28-oic acid 28-O-beta-D-glucopyranoside (3), 3,5,6-trihydroxydehydro-alpha-ionol 9-O-beta-D-glucopyranoside (4), quadranoside III (5), rosmarinic acid (6), caffeic acid (7), and luteolin (8). All the isolated compounds were evaluated for their antioxidant, antimicrobial, antimalarial, and cytotoxic activities. Only rosmarinic acid exhibited substantial antioxidant and antimicrobial activities, whereas sulfated terpenes showed considerably lower or no antimicrobial activity.