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

Table 2

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

Polyphenols	Rt (min)	UV (nm)	UV-DAD/VIS bands (nm); in 70% methanol	Class	Mg⋅g^−1 dry weight
Taxifolin	17.48	280	290, 327sh	Flavanol	21.76 ± 0.030
Genistin	19.79	320	259, 323sh	Isoflavone	16.75 ± 0.040
Genistein	22.73	320	259, 332sh	Isoflavone	12.01 ± 0.030
Quercetin-3-O-rutinoside	23.88	370	256, 266sh, 351	Flavonol	1.58 ± 0.030
Quercetin-3-O-glucoside	23.99	370	255, 266sh, 348	Flavonol	1.23 ± 0.010
Ferulic acid	24.32	320	244, 296sh, 324	Hydroxycinnamic acid	0.27 ± 0.002
Biochanin A-glucoside	30.66	320	265, 322sh	Flavone	1.37 ± 0.002
Apigenin	32.65	370	229, 267sh, 341	Flavone	0.44 ± 0.002
Biochanin A	34.88	320	265, 323sh	Flavone	2.89 ± 0.004
Total of hydroxycinnamic acids					0.27 ± 0.002
Total of flavonols					24.57 ± 0.100
Total of flavone					4.70 ± 0.008
Total of isoflavone					28.76 ± 0.070
Total of polyphenols identified					58.30 ± 0.180

Values expressed as mean ± standard deviation of three replicates.