Exploring Silybum marianum L. seeds from Pakistan for its antibacterial, antioxidant, antidiabetic activities, and phytochemical analysis.

Abstract

In this study, various extracts, including methanol (SMLM), hydro-ethanol (SMLE), n-hexane (SMLH), and aqueous (SMLA) were formulated from the seeds of Silybum marianum L. and subjected to phytochemical assessment, HPLC, FTIR analysis, and different in vitro bioassays. The qualitative analysis revealed the presence of all representative groups, except alkaloids, in the samples. The quantitative examination indicated that the SMLE extract exhibited the highest total flavonoid contents and highest entire phenolic concentrations. HPLC analysis of the SMLM extract identified chlorogenic acid, gallic acid, kaempferol, benzoic acid and HB acid which were reported for the first time from S. marianum. In terms of antibacterial activity, the SMLH extract demonstrated a significant zone of inhibition (34 ± 0.5 mm) against Gram-positive bacterial species, Staphylococcus aureus. In antioxidant assays, the SMLM extract displayed the highest scavenging potential against DPPH radicals and exhibited a significant IC₅₀ of 4.8 ± 1.2 μg/mL, indicating notable efficacy. Subsequently, the SMLE extract demonstrated an IC₅₀ of 20.17 ± 0.4 μg/mL. In the context of antidiabetic evaluation, the SMLM extract displayed the highest effectiveness, revealing an IC₅₀ value of 5.2 ± 0.07 μg/mL. To conclude, the assessed samples, such as the SMLM and SMLE extracts, exhibit remarkable capabilities in the studied activities, potentially attributed to the existence of bioactive compounds.