Fig. 8

UV–vis spectra associated with flavonoids, possibly due to dyeing with weld, recorded during the HPLC–DAD analysis of: a sample AS2-1 (retention time: 8.9 min); b sample AS14 (retention time: 11.9 min); c sample AS7 (retention time: 17.8 min); d sample AS3 (retention time: 23.1 min). In all panels, the yellow spectrum corresponds to the HPLC–DAD analysis of standard luteolin (retention time: 19.3 min)