Phenolic profile and biological activities of Aloe barbadensis (Miller) from western Algeria

Abstract

Aloe vera is widely used in conventional medicine in Algeria to treat various diseases. This study aims to evaluate the chemical composition and biological activities of Aloe vera collected from western Algeria. Two extracts of ethanolic (EEA) and aqueous (AEA) were used to determine the total phenolic and flavonoid content. HPLC was applied to determine the amount of 15 compounds they contain, while the antioxidant activity was determined by the DPPH method. The antimicrobial activity experiment was conducted against five selected bacterial strains. Finally, an in vivo study on Swiss albino mice was conducted to discover the toxicity using Lorke’s method and anti-inflammatory activity using the Carrageenan method. The EEA extract shows the highest total phenol content of 37.00±0.37mg GAE/g and total flavonoid content of 9.14±0.19 mg CE/g. The AEA contains hydroxybenzoic and benzoic acid with other ingredients (0.84 and 0.82 mg/g, respectively). The EEA contains 0.93 mg/g of benzoic acid. Aloe vera has antioxidant activity with IC50 values equal to 0.821 mg/ml for EEA and 1.993 mg/ml for AEA. The AEA inhibits E. coli and S. aureus with a bacteriostatic effect; EEA is the best inhibitor of S. aureus and S. mutans with the bactericidal effect. Aloe vera is practically nontoxic (LD50 is 3800 mg/kg of the AEA and superior to 5000 mg/kg of EEA). The AEA gives the best inhibition of edema, 85.96% at (100 mg/kg). Aloe vera leaves are an important resource of polyphenols, which have interesting antioxidant power, and antimicrobial and anti-inflammatory activities. DOI: http://dx.doi.org/10.5281/zenodo.7274997

Keywords

• Aloe vera
• Antimicrobial
• Antioxidant
• Anti-inflammatory
• HPLC