Phenolic profiles, antimicrobial and cytotoxic properties of both micropropagated and naturally growing plantlets of calamintha sylvatica subsp. sylvatica Bromf.

Abstract

A rapid micropropagation protocol was designed to produce Calamintha sylvatica plantlets by using nodal segments as explants for the shoot formation. 6-BA favored the highest shoot formation and biomass yield, whilst kinetin was found superior for the highest shoot length (38.97 ± 2.85 mm) and node numbers (2.89 ± 0.63). Rosmarinic acid was detected as major phenolic acid, ranging from 7.59 mg/100 g to 81.44 mg/100 g. Hexane extracts from natural and in vitro propagated plantlets showed activity only against Staphylococcus aureus ATCC 25923 with MIC values at 6.25 and 3.33 m/mL, respectively while in the latter case, extracts from natural plantlets exerted higher cytotoxic activity than those of micropropagated ones (IC50 values were 83 μg/mL and 98 μg/mL on HeLa cells, respectively). C. sylvatica showed high micropropagation performance and produced remarkable amount of rosmarinic acid in vitro as well as antimicrobial and cytotoxic effect.