Antibacterial Activity and Molecular Docking Analysis of the Stem Bark Extracts of Persea americana Mill (Lauraceae) doi.org/10.26538/tjnpr/v6i6.27

Abstract

Persea americana is utilized as food in most countries. Its excellent nutritional benefit and bioactivities have been extensively evaluated. Therefore, this study aims to determine the in-silico and in-vitro bioactivity of its bark extracts against multidrug-resistant (MDR) bacteria isolated from fish pond effluents. Extraction of the plant was done using the maceration method in ethanol, methanol, acetone, cold water, and hot water for 7 days and screened against MDRbacteria. Phytochemical screening was carried out on all the plant extracts. One hundred microliters of the crude extract were used for the minimum inhibitory concentration (MIC) test. Different bioactive molecules in the hot-water extract were identified using Gas chromatography-mass spectrometry (GC-MS) method and  valuated using molecular docking tools to inhibit penicillin-binding protein (PBP) and DNA gyrase (DNAg). Phytochemicals such as tannins, flavonoids, saponins, steroids, alkaloids, and glycosides were present in all the extracts. Inhibition zones ranging from 0-20mm or methanol bark (MB), hot-water bark (HWB), and cold-water bark (CWB), ethanol bark (EB) (0-18mm), acetone bark (AB) 0-13mm at 100 mg/mL of the crude extract were observed. The MIC of the extracts against multi-drug resistant isolates in EB, MB, and HWB were at 6.25 mg/mL, while those of AB and CWB were at 12.5 mg/mL and 12.5 mg/mL, respectively. GC-MS analysis showed the presence of 105 compounds. Likewise, molecular docking revealed that certain phytoconstituents examined in this study had higher binding affinity compared to conventional antibiotics. Therefore, P.americana bark possesses promising bioactive chemicals that can be used as antibacterial agents.