Phytochemical and Antioxidant Analysis and Antibacterial Efficacy of Methanolic Extracts of Saffron (Crocus sativus) from Taliouine Region in Morocco

Saffron (Crocus sativus L.) is prized for its distinctive characteristics, which include flavor, color, aroma and therapeutic uses. Although the antioxidant properties of saffron metabolites are well documented, most studies focus on the stigmas, while other parts of the plant, notably the vegetative tissues remain little explored. Extracts from various parts of saffron were obtained by maceration in methanol, followed by filtration and vacuum evaporation. Flavonoids, polyphenols and tannins were quantified by colorimetric methods using aluminum chloride, Folin-Ciocalteu and vanillin reagents, respectively. Antioxidant activity was assessed by 2, 2-diphényl-1-picrylhydrazyl (DPPH) and fluorescence recovery after photobleaching (FRAP) tests and expressed as Half-Maximal Inhibitory Concentration (IC50). Molecular concentration and identification were determined by gas chromatography-mass spectrometry (GC-MS) and antibacterial activity was evaluated with the agar diffusion method against Gram positive and Gram negative strains. Results showed that extracts from several plant locations (stigmas, bulbs, flowers and leaves) had comparable levels of polyphenols (1563, 1098, 1202 and 169 mg EAG/g Dry Matter (DM), respectively), flavonoids (138, 109, 122 and 106 mg EQ/g DM) and tannins (3614, 318, 692 and 181 mg EC/g DM). In terms of antibacterial activity, the bulbs were found to outperform the stigmas, particularly against Gram positive bacteria. For antioxidant activity, methanolic extracts of flowers showed an IC50 of 22.91 mg/mL, those of stigmas an IC50 of 32.27 mg/mL, those of leaves an IC50 of 54.72 mg/mL and those of bulbs an IC50 of 61.47 mg/mL. In contrast, leaf and bulb extracts showed lower activity, with IC50 of 54.88 and 61.89 mg/mL, respectively, well above the IC50 for ascorbic acid (0.082 mg/mL). These results highlight the richness of aerial parts, particularly the flowers and stigmas, in secondary metabolites responsible for their high antioxidant activity. These results underscore that saffron flower and stigma extracts could serve as effective natural alternatives to synthetic antioxidants and antimicrobials in pharmaceutical and cosmetic products