Phytochemical Composition and Antibacterial Activity of Hydroalcoholic Extracts of Pterospartum tridentatum and Mentha pulegium against Staphylococcus aureus Isolates

Table 3

Average content of polyphenols and respective retention time (Rt) and wavelengths of maximum absorption in the visible region () in M. pulegium extracts (by elution order).

Polyphenols	Rt (min)	UV (nm)	UV-DAD/VIS bands (nm); in 70% methanol	Class	Mg⋅g^−1 dry weight
p-Hydroxybenzoic acid	13.46	280	227, 260sh, 295	Hydroxybenzoic acid	0.212 ± 0.004
Chlorogenic acid	17.95	320	242, 300sh, 327	Hydroxycinnamic acid	0.387 ± 0.004
(+)-Catechin	18.10	280	231, 280	Flavan-3-ols	0.212 ± 0.004
Caffeic acid	21.32	320	243, 296sh, 324	Hydroxycinnamic acid	0.230 ± 0.001
Quercetin-3-O-rutinoside	22.96	370	256, 266sh, 351	Flavonol	0.144 ± 0.003
Quercetin-3-O-glucoside	23.63	370	255, 266sh, 348	Flavonol	0.140 ± 0.002
Neohesperidin	24.84	280	283, 326	Flavanone	0.628 ± 0.001
Luteolin-7-O-glucoside	25.31	370	254, 266, 349	Flavone	0.201 ± 0.004
Diosmin	26.04	370	253, 268, 339	Flavone	0.623 ± 0.006
Rosmarinic acid	26.78	320	249, 299sh, 330	Hydroxycinnamic acid	0.287 ± 0.006
Ferulic acid	27.55	320	241, 296sh, 324	Hydroxycinnamic acid	0.277 ± 0.003
Apigenin	32.65	370	235, 267sh, 341	Flavone	0.323 ± 0.002
Total of hydroxybenzoic acids					0.212 ± 0.004
Total of hydroxycinnamic acids					1.181 ± 0.014
Total of flavan-3-ols					0.212 ± 0.004
Total of flavonols					0.284 ± 0.005
Total of flavones					1.147 ± 0.012
Total of flavanones					0.628 ± 0.001
Total polyphenols identified					3.664 ± 0.040

Values expressed as mean ± standard deviation of three replicates.