Phytochemical analyses and evaluation of antioxidant, antibacterial and toxic properties of emblica officinalis and terminalia bellirica fruit extracts

Objective: The present study deals with the investigation and evaluation of phytoconstiuents of Emblica officinalis and Terminalia bellirica fruit extracts for their antibacterial and antioxidant potential, as well as their potential acute toxicity. Methods: Phytochemical analyses was performed besides antioxidant activity of the extracts was alaso determined using diphenylpicrylhydrazyl (DPPH), total phenolic content (TPC), total flavonoid content (TFC) assays. Antimicrobial activity of the extracts was evaluated by agar well diffusion assay. Results: The extracts prevented the growth of both Gram-positive and Gram-negative bacteria. The E. officinalis aqueous fruit extract (EOA) and E. officinalis methanolic fruit extract (EOM) both exhibit tannins, saponins, phenols, and carbohydrates, whereas alkaloids and flavonoids are found only in EOM, and glycosides showed their presence in aqueous extract only. In contrast, T. bellirica aqueous fruit extract (TBA) and T. bellirica aqueous fruit extract (TBM) both contains alkaloids, tannins, coumarins, flavonoids, and phenols. While carbohydrates are present barely in TBM, TBA extract showed the presence of saponins and glycosides. The TPC results show that EOM (528±0.013) has the highest phenolic content in it followed by EOA (509±0.003), TBM (284±0.06), and TBA (280±0.036). In TFC analysis too, EOM (154±0) showed a higher concentration range of flavonoids followed by EOA (142±0), TBM (126±0.017), and TBA (119±0.007). In DPPH scavenging assay, EOM (86.88±0.310) showed maximum % inhibition followed by EOA (85.32±0.414), TBM (80.57±0.569), and TBA (75.55±0.362), respectively. Antibacterial assay showed varying results for different bacterial strains such as, for EOA (10±1) demonstrated highest inhibition against Escherichia coli, EOM (11.5±0.5) exhibited maximum inhibition against Staphylococcus aureus, for Klebsiella pneumoniae EOA (13±2) displayed maximum inhibition and in case Pseudomonas aeruginosa too EOA (12.5±0.5) showed maximum inhibition while TBM and TBA too showed significant amount of inhibition against test bacterial strains. The antibacterial and antioxidant activities of the extracts were found to be positively associated with the TPC and TFC of the extracts. This study was conducted to identify the phytochemical composition of the fruit extracts of the two plants, their antioxidant and antibacterial potential, along with their neuroprotective and nootropic role. To establish their neuroprotective role, acute toxicity study was conducted on Wistar rats to establish the safety of the extracts. Conclusion: The current study demonstrates and compares the antioxidant and antibacterial activities of the fruit extracts of T. bellirica and E. officinalis and acute toxicity study further demonstrates that the extracts used are safe to conduct neuroprotective studies.