Antibacterial, antioxidant and phytochemical investigation of Albizia Anthelmintica leaves, roots and stem bark

A research thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science in Industrial Biochemistry

Albizia anthelmintica belongs to the family Fabaceae. The plant is traditionally used to treat symptoms of microbial infections in both humans and animals. The present study was designed to evaluate the phytochemical content, antibacterial and antioxidant activities of A. anthelmintica leaves, roots and stem bark ethanol extracts. Antibacterial activity was carried out by means of the agar disc diffusion method. The anti-oxidative activities of the extracts were determined by means of ferric reducing antioxidant power (Fe 3+- Fe 2+), phosphomolybdenum reduction and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays and phytochemical screening was used to determine the major classes of compounds present in the specific plant parts. Phytochemical screening revealed the presence of alkaloids, saponins and diterpenes in roots and bark extracts, flavonoids in leaves extract, tannins in roots extracts, and phenolic compounds were detected in all three extracts. The root extract exhibited the highest total phenolic and flavonoid content of 1741.08 ± 0.05 mg GAE/100 g and 366.80 0.02 ± mg QEE/100 g, respectively. The extracts demonstrated dose dependent varying degrees of anti-oxidative efficacy in the phosphomolybdenum reduction, iron (III) reduction and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays. For the DPPH assay, IC50 values of 0.018 ± 0.01, 0.019 ± 0.01 and 0.024 ± 0.01 mg/mL were obtained for the root, leaf and bark extracts, respectively. All extracts were active against Staphylococcus aureus, Shigella sonnei and Serratia marcescens but did not show activity against Enterococcus faecalis and alcaligenes faecalis. The results from the study show that Albizia anthelmintica extracts possess compounds with antibacterial as well as anti-oxidative properties, making this plant species a good source for potent antibacterial and anti-oxidative agents. The findings of this study will add value to the traditional uses of A. anthelmintica, and conservation is necessary due to the significant medicinal properties demonstrated by the plant.