Analysis of total polyphenol and flavonoid content, antioxidant potential and antibacterial activity of Parkia speciosa pod and seed extracts

Parkia speciosa Hassk is a legume that is widely utilized as a cooking ingredient and valued for its medicinal properties throughout the Nagaland state in India. This research offers an overview of the phytochemical content, antioxidant properties and antibacterial activity of P. speciosa pods and seeds extracted in various solvents. The qualitative analysis revealed the presence of diverse compounds, including tannins, saponins, flavonoids, terpenoids and alkaloids across all extracts. The methanolic extract exhibited the highest levels of phytoconstituents, with total polyphenol content (TPC) and total flavonoid content (TFC) measuring 581.93 mg GAE g⁻¹ and 360.83 mg CE g⁻¹ respectively. Antibacterial activity differed based on the solvent and the bacterial type, with methanolic extracts demonstrating significantly greater effectiveness than acetone and chloroform. Additionally, Escherichia coli was more susceptible than Staphylococcus aureus. The antioxidant activity was significantly affected by the concentration of extracts and solvents used (p < 0.05), with methanolic extract demonstrating the highest scavenging activity, followed by acetone and chloroform extracts. Although pod extracts had higher TPC and TFC as well as stronger antioxidant capacity, seed extracts exhibited higher antibacterial activity. Parkia speciosa is not only an edible plant but also a significant source of medicinal properties, offering great potential for use in the pharmaceutical industry.