Chemical composition and biological activity of extracts from Salvia bicolor Desf. growing in Egypt.

A petroleum ether extract (PEE) and a methanolic extract (ME) of aerial parts of Salvia bicolor Desf were prepared, and their chemical compositions and antioxidant, anti-inflammatory, analgesic and antimicrobial activities were evaluated. GC/MS analysis of the PEE revealed the presence of 20 compounds in the unsaponifiable matter, among which β-sitosterol and β-amyrin (constituting 24.75% and 15.62%, respectively) were the main constituents, and 21 fatty acids, with linolenic acid and erucic acid being the main fatty acid constituents (21.65% and 16.65%, respectively). HPLC/MS analysis of the methanol extract for individual phenolics revealed the presence of 14 phenolic acids; protocatchuic acid was predominant (75.22 mg/g dry sample), followed by p-coumaric, gallic and synergic acids (70.27, 68.26 and 54.38 mg/g dry weight, respectively). HPLC/MS analysis of flavonoid contents revealed the presence of five flavonoid compounds, among which luteolin 7-O-glucoside and apigenin were the major constituents (120.25 mg/100 g dry sample and 88.48 mg/100g dry sample, respectively). The antioxidant activities of both extracts were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the total antioxidant capacity was determined in terms of GAE (gallic acid equivalents). Anti-inflammatory and analgesic activities were evaluated using the rat paw edema and hot plate testing methods, respectively. The antimicrobial activities of both the PEE and ME were examined by means of the disk-diffusion method. The Salvia bicolor PEE and ME exhibited significant antioxidant, anti-inflammatory, and analgesic properties, in addition to antimicrobial effects against the selected microorganisms.