Antibacterial activity of orsellinates

In order to obtain new compounds with antibacterial activity, the derivatives 2,4-dihydroxy-6-methylbenzoic acid (orsellinic acid) and 2,4-dihydroxy-6-methylbenzoates (orsellinates) were obtained through alcoholyses of lecanoric acid. All these substances were tested against Gram-positive and Gram-negative bacteria by a microdilution method. Staphylococcus aureus, Xanthomonas campestris var. vesicatoria and Ralstonia solanacearum were most sensitive to n-propyl 2,4-dihydroxy-6-methylbenzoate, n-pentyl 2,4-dihydroxy-6-methylbenzoate and n-hexyl 2,4-dihydroxy-6-methylbenzoate with MIC (Minimal Inhibitory Concentration) values ranging from 62.5 to 7.8 µg×mL1. These results showed that homologation in carbon chain may lead to compounds with more pronunced activities.