Biological activities of Umbilicaria crustulosa (Ach.) Frey acetone extract

This paper reports for the first time the effect of an acetone extract of Umbilicaria crustulosa on the micronucleus distribution of human lympho­cytes, and on the cholinesterase activity and antioxidant activity by the cupric ion reducing antioxidant capacity (CUPRAC) method. Additionally, the total phenolic compounds (TPC) and the antioxidant properties were estimated via DPPH, ABTS and TRP assays. Moreover, the antibacterial activity against two Gram-positive and three Gram-negative bacteria were determined. Acetone extract of U. crustulosa at concentration of 1 and 2 µg mL-1 decreased a fre­quency of micronuclei (MN) by 10.8 and 16.8 %, respectively, acting more or slightly less than the synthetic protector amifostine (AMF, WR-2721, 11.4 %, at concentration of 1 µg mL-1). The tested extract did not inhibit cholinesterase activity nor did it exhibit activity toward the examined bacteria. The extract reduced the concentration of DPPH and ABTS radicals by 88.7 and 96.2 %, respectively. Values for total reducing power (TRP) and cupric reducing cap­acity (CUPRAC) were 0.6197±0.0166 µg ascorbic acid equivalents (AAE) per mg of dry extract, and 19.7641±1.6546 µg trolox equivalents (TE) per mg of dry extract, respectively. The total phenol content was 350.4188 ±14.587 µg gallic acid equivalents (GAE) per mg of dry extract. The results of the present study showed that U. crustulosa acetone extract is a promising candidate for in vivo experiments considering its antioxidant activity and protective effect on human lymphocytes.