Phytochemical screening and antimicrobial activities of almonds extracts from kernel of two mango (Mangifera indica L.) varieties grown in Korhogo (North of Ivory Coast)

Mango (Mangifera indica L.) is a fruit marketed worldwide. It is a third fruit exported by Côte d’Ivoire with 10000-15000 tons for annual production among 150000 tons. The by-products of mango such as kernel almonds are not pratically valued. Therefore, this work aims to determine phytochemical compound and evaluate antimicrobial activity of extracts from kernel almonds of mango varieties Kent and Keitt. Aqueous and hydroethanolic extracts were prepared with almonds flours of Kent (EtaqKE and EethKE) and Keitt (EtaqKI and EethKI) varieties. Phytochemical screening of the four extracts was performed by tube tests and thin layer chromatography. Antimicrobial activity of these extracts was evaluated in vitro with agar broth dilution method against three bacteria (Escheichia coli, Staphylococcus aureus and Pseudomans aeruginosa) and three fungi (Candida albicans, Trichophyton rubrum and Trichophyton mentagrophytes) involved in skin infections. Phytochemical screening revealed presence of polyphenols, sterols, terpenes, flavonoids, anthraquinones and saponins in all the four almonds extracts. Antimicrobial tests showed that, extracts EethKE and EethKI are the most active with MIC and MBC ranging respectively from 0.39 to 12.5 mg/mL and 12.5 to 50 mg/mL for bacteria. The extract EtaqKI is more active on bacteria and has a bactericidal action on P. aeruginosa and E. coli strains with ratio CMB/CMI of 4. The four almonds extracts have any activity on fungi strains tested. The presence of secondary metabolites and antibacterial activities of extracts of almond from kernels of mango Kent and Keitt varieties demonstrate that these extracts could have therapeutic and cosmetic applications.