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In this research, a comparative analysis was carried out to characterize the content of phenolics and biological activities of the whole plant of Papaver rhoeas L. (P. rhoeas) from different geographical regions of Morocco, as well as to determine the synergistic antimicrobial and antioxidant effects of all parts of P. rhoeas. The determination of total polyphenol content (TPC), total flavonoid content (TFC), and total anthocyanin content (TA) in extracts of whole plants of P. rhoeas from three different geographical regions: Taounate (P1E), Fez (P2E), and Sefrou (P3E) were estimated by the Folin–Ciocalteu reaction, the aluminum trichloride method and the differential pH absorption technique, respectively. Two tests were used to evaluate the antioxidant power of our samples: the DPPH test and the TAC test. Using two methods, disk diffusion and microdilution, antimicrobial activity was studied against four pathogenic bacteria and one yeast. The results of TPC, TFC, and TA show that the P3E sample is the richest in polyphenols, flavonoids, and anthocyanins, with values 37.33 ± 1.307 mg GAE/g, 4.72 ± 0.346 QE/g, and 1.77 ± 0.026 CGE/g, respectively. In addition, P3E showed the best antioxidant activity with an IC50 = 0.27 ± 0.001 mg/mL and TAC = 9.99 ± 0.768 mg AAE/g, respectively. The results of antimicrobial activity showed significant activity on almost all the tested strains. The lowest MIC was recorded for P3E against E. coli ATCC 25922 and E. coli CIP 53126 strains at 0.78 and 0.78 mg/mL, respectively. These results show that the geographical region can influence the plant’s phytochemistry and then these biological activities.

Anchusa italica Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of Anchusa italica Retz. We first determined the content of phenolic compounds and flavonoids using Folin–Ciocalteu reagents and aluminum chloride (AlCl3). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of Escherichia coli, two strains of Klebsiella pneumoniae and coagulase-negative Staphylococcus, and one fungal strain of Candida albicans. The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC50 of 0.11 µg/mL) in comparison to ascorbic acid (IC50 of 0.121 µg/mL). The DPPH test determined an IC50 of 0.11 µg/mL for the root extract and an IC50 of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC50 of 0.16 µg/mL) and BHT (IC50 0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00–16.00 mm for the root extract and 11.67–14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against E. coli (ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of Anchusa italica Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols.