Major Phytochemical Compounds, In Vitro Antioxidant, Antibacterial, and Antifungal Activities of Six Aqueous and Organic Extracts of Crocus sativus L. Flower Waste

Abstract

Purpose After being considered as a neglected product, agricultural waste is nowadays considered of paramount importance. It has become a source of many chemical compounds with industrial, pharmaceutical, and food applications. This study aims to evaluate the primary phytochemical content, the antioxidant properties, and the antimicrobial activities of different extracts of saffron flower waste (SFE) against bacterial and fungal strains involved in diverse pathologies in southern Morocco. Methods Total phenolic and flavonoid contents were determined. The antioxidant potentials were assessed by DPPH, FRAP, and β-carotene assays. The antimicrobial activity against four bacteria and four fungi was also evaluated. The findings in terms of the relationships between phytochemical content and all activities were depicted by PCA analyses. Results SFEs contained large amounts of phenolic and flavonoid compounds that contribute to the significant antioxidant activities. Diethyl ether (DE), n-Butanol (n-B), and Ethyl acetate (EA) fractions respectively exhibited more DPPH scavenging capacity, FRAP reducing power, and β-carotene bleaching inhibition. DE and EA have a remarkable effect mainly against Staphylococcus aureus strain, compared to Listeria monocytogenes, Escherichia coli and Klebsiella pneumoniae. Both SFEs showed antifungal antagonism towards key fungi species involved in post-harvest mold and crop yield losses. Botrytis cinerea was more susceptible than Fusarium solani, Penicillium expansum, and Penicillium digitatum. Conclusion These results reveal new data about extracts obtained from SFE that could be a potential source of natural antioxidant and antimicrobial agents opening new possibilities for their applications in the food system as a natural preservative and a sustainable alternative to conventional ingredients.

Optimization of Bioactive Compound Extraction from Saffron Petals Using Ultrasound-Assisted Acidified Ethanol Solvent: Adding Value to Food Waste

“…Kaempferols and anthocyanins are the primary chemicals with a high phenolic content, according to the earlier study, which also showed that saffron flower waste includes naturally occurring flavonoid and phenolic compounds. Factors such as origin, altitude, growth circumstances, and picking times can be blamed for variations in these chemicals [44]. This may help to explain why binary solvent systems generate higher yields than those of monosolvent systems.…”

Stigmas and Petals of Crocus sativus L. (Taliouine, Morocco): Comparative Evaluation of Their Phenolic Compounds, Antioxidant, and Antibacterial Activities

“…The reproductive method of this particular species is through vegetative propagation using bulbs [ 12 , 13 ]. It is cultivated in many places worldwide, such as Iran, India, Afghanistan, Morocco, and Euro-Mediterranean countries such as Greece, Spain, and Italy, with a world production of 418 t year 1 [ 14 ].…”

“…According to the National Agency for the Development of Oasis and Argan Zones (ANDZOA), national saffron production is estimated at over 10 t in 2020, located in the Taliouine and Taznakht area, places Morocco fourth in terms of production after Iran, India, and Greece [ 12 ]. Saffron is the most expensive spice in the world, nicknamed “red gold.” Its labor-intensive cultivation takes around 150,000–200,000 (78 kg) fresh flowers and 160,000 petals to produce 1 kg of saffron [ 13 ], which explains its scarcity and high cost.…”

“…They have been associated with numerous pharmacological effects [ 22 ]. The results of previous studies have suggested that different parts of Crocus sativus L. can be used for their antioxidant activity [ 23 , 24 ] and antibacterial effects against specific bacteria [ 12 , 25 , 26 ].…”

Antibacterial Activity of Crocus sativus L. Petals Extracts against Foodborne Pathogenic and Spoilage Microorganisms, with a Special Focus on Clostridia

“…Previous studies clearly suggest that saffron petals can be used to obtain extracts with different properties such as antioxidant activity and, in particular, antibacterial activity against some Gram-positive and Gram-negative bacteria and fungi. [ 25 , 26 ]. For instance, Asgarpanaha et al described a significant antibacterial activity of C. sativus petals methanolic extract against Staphylococcus aureus , Bacillus cereus , Salmonella Typhi, Escherichia coli and Shigella dysenteriae [ 27 ].…”