Wound healing, antioxidant and antibacterial activities of polyphenols of Psidium guajava L. leaves

The current study aimed to evaluate the in vivo wound healing potential of Psidium guajava L. by wound excision model owing to its ethnomedicinal use as a wound healer since olden times. P. guajava leaves were extracted using methanol -chloroform (1:1). Phytochemical analysis of P. guajava leaves extract (PGLE) was performed using total phenolic content (TPC) assay, total flavonoid content (TFC) assays, and High-performance liquid chromatography (HPLC). In vitro, antioxidant potential (DPPH radical scavenging assay, total antioxidant capacity (TAC) assay, and ferric reducing antioxidant power (FRAP) assay), antibacterial activity (broth microdilution method), and hemolytic analysis of PGLE were performed. In vivo, wound healing proficiency of PGLE (10, 5, and 2.5% w/w) was determined by estimating hydroxyproline and endogenous antioxidant markers. TPC and TFC were found to be 57.5 +/- 0.37 mu g gallic acid equivalent/mg extract and 32.1 +/- 0.24 mu g quercetin equivalent/mg extract, respectively. A prominent concentration of polyphenols was demonstrated by HPLC-based quantification with the highest value of rutin which is 12.3 +/- 0.12 mu g/mg extract. A noteworthy DPPH radical scavenging activity with an IC50 of 40.7 mu g/ml, TAC, and FRAP i.e., 159.3 +/- 0.11 and 206.1 +/- 0.17 mu g ascorbic acid equivalent/mg extract, respectively were exhibited by PGLE. Significant antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeroginosa, and Methicillin-resistant Staphylococcus aureus with the minimum inhibitory concentration of 250, 400, 400, and 500 mu g/ml respectively was depicted by PGLE and found biocompatible with 1.1 +/- 0.16% hemolysis. Significant wound contraction, faster epithelialization (9 +/- 1 days), extensive fibroblast proliferation, and substantial neovascularization were observed in the 10% PGLE-treated group also evident by histopathological examination. Significant hydroxyproline (15.7 +/- 1.02 mu g/mg tissue), catalase, peroxidase (5.4 +/- 0.26 and 6.1 +/- 0.35 U/mg tissue) and glutathione content (9.7 +/- 0.06 mmol/mg tissue) with p -value of less than 0.01 was demonstrated by 10% PGLE. A reduction in lipid peroxidation (0.5 +/- 0.07 mmol/mg tissue) was also observed at the same concentration (10%). These findings scientifically validate the potent pharmacological effects of P. guajava phytochemicals and suggest their promising role as wound healing agents. (c) 2023 Published by Elsevier B.V. on behalf of SAAB.