2.4.5 Photosynthetic Pigments
Photosynthetic pigments were determined according to Arnon (1949). The sample of S. hieraciifolia (0.1 g) was homogenized in 5 ml of 80% acetone. The homogenate was centrifuged at 5000 g for 5 min at room temperature. The absorbance of the supernatant was measured at 663, 645 and 450 nm by spectrophotometrically (Nicolet evolution 100, Thermo Scientific, USA). The measurement of total chlorophyll (Chl) and carotenoid (Car) contents were determined by the equations developed by Lichtenthaler and Wellburn (1983).