In vitro Antimicrobial, Antioxidant, and Antidiabetic Activities of Extracts of Senecio Abyssinicus Leaves

Abstract

Despite advancement in technology and healthcare delivery, infectious diseases still ravage humanity, plants-based remedies still remain our major kick back against them. The phytochemical screening, antimicrobial, antioxidant, and anti-hyperglycemic activities of n-hexane, ethyl acetate, and methanolic extracts of Senecio abyssinicus leaves were investigated in this study, in line with SDG 3, 9 and 12 goals, following standard methods. The in vitro antioxidant properties were tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2ʹ-azinobis(3-ethylbenzthiazoline-6-sulphonate) (ABTS^·+) radical scavenging assays. Agar diffusion-pour plate methods was used to evaluate the antimicrobial activities of the extracts. The phytochemical evaluation of the extracts unveiled the presence of polyphenols, steroids, terpenoids, alkaloids, and cardiac glycosides. The methanol extracts showed varying degrees of antibacterial activity against the tested bacterial: Klebsiella pneumonia, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi at concentrations between 6.25 – 200 mg/mL relative to Gentamycin. Furthermore, it showed significant activity on the tested fungal strains: Rhizopus stolons,, Aspergillus niger, Pneumonae notatum, and Candida albicans between 12.5 – 200 mg/mL, with regards to Tioconazole. The methanol extract had the greatest inhibitory effect (IC₅₀, 26.59µg/mL) on α-glucosidase enzyme, with respect to Acarbose (IC₅₀ 11.31 µg/mL). Similarly, it showed low ABTS^·+ and DPPH antioxidant activity (IC₅₀ ˃50 µg/mL) when compared to the standard Trolox (IC₅₀ 5.91 µg/mL) and Ascorbic acid (IC₅₀ 12.24 µg/mL) respectively. These findings demonstrated that S. abyssinicus leaves exhibits moderate to significant antimicrobial, antioxidant, and antidiabetic activities. Thus, could be considered as a good source of antioxidant, hypoglycemic, and antimicrobial agents for good health and well-being.