Phytochemical composition, antioxidant and antibacterial properties of methanol stem and leaf extracts of Croton bonplandianus Baill

Abstract

The increasing demand for natural antioxidants in the food and pharmaceutical sectors has driven the search for plant species with notable bioactive properties. To fulfil the demand for natural antioxidants, different plants including Croton spp. have been explored. However, the antioxidant activities of Croton bonplandianus Baill plant growing in Varanasi and surrounding regions have not been assessed to date. C. bonplandianus thrives in diverse habitats and exhibits a range of bioactivities, such as wound healing, anti-arthritic, antimicrobial, anticancer, and other therapeutic potentials. Therefore, the present study aimed to quantify total phenolic and flavonoid contents in methanol extracts of the leaf (LME) and stem (SME) of C. bonplandianus plant. Further, extracts were analyzed for in-vitro antioxidant and antibacterial activities. The results depicted that total phenolics (mg GAE/g dw) and flavonoids (mg QE/g dw) content were higher in LME (63.2 and 4.3, respectively) of C. bonplandianus as compared to the SME (30.5 and 3.5, respectively). Further, the results revealed DPPH (%), ABTS (%) and FRAP [µM Fe (II)/g dw] activities in LME (78.7, 83.4 and 203.8, respectively) were also higher than SME (72.3, 71.73 and 169.7, respectively). IC<inf>50</inf> values were recorded as 0.8 mg/ml and 5.8 mg/ml for LME and SME, respectively. GC–MS investigation of LME and SME showed the presence of Undecane 2,6-dmethyl (28%) followed by cyclonasilaxane (19%), octadecanoic acid (6.62%) and hexadecanoic acid (4.18%) as major compounds. Both the extract potentially possessed antibacterial properties against E. coli. The findings also demonstrated that heavy metal concentration in soil, leaf, and stem was found within Indian norms. The present study concludes that both, the leaf and stem of C. bonplandianus plant are rich in phenolic and possess antioxidant and antibacterial activities. Therefore, it is suggested that C. bonplandianus be further explored and used therapeutically to fulfill the current demand for natural antioxidants. © The Author(s) under exclusive licence to Society for Plant Research 2024.