Antioxidant and antimicrobial activities of two edibles spices from Cameroon and quantification of their major phenolic compounds

This study aimed to analyze the phytochemical composition, antioxidant capacity, antimicrobial activity and the phenolic profile of Aframomum melegueta and Afrostyrax lepidophyllus methanolic extracts. The mean phenolic compound contents were 160.77 +/- 6.74 and 46.63 +/- 0.93mg GAE/g extract, while that of the tannins was 136.40 +/- 0.94 and 8.72 +/- 1.60mg GAE/g, respectively for A. melegueta and A. lepidophyllus. Similarly, the flavonoids were higher in A. melegueta extract (70.62 +/- 0.90mg CE/g) compared to A. lepidophyllus extract (3.95 +/- 0.14 mg CE/g). A. melegueta extract showed strong antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP) and Phosphomolybdenum antioxidative power (PAP) tests compared to A. lepidophyllus extract. A. lepidophyllus extract showed strong antibacterial activity with a minimal inhibitory concentration (MIC) range of 312.5 to 5000 mu g/mL. A. melegueta extract has exerted a bactericidal effect against Staphylococcus aureus with minimal bactericidal concentration (MBC) = 5000 mu g/mL. The qualitative and quantitative analysis of the phenolic compounds were carried out by HPLC coupled to a diode array detector. The most abundant flavonoid in A. melegueta was quercetin. Among the quantified phenolic acids, gallic acid was the most abundant in both spices extracts. The results of this study showed that A. melegueta extract has promising potential to the control of non-communicable diseases and could be used with A. lepidophvllus extract as natural sources of antimicrobial agents. (C) All Rights Reserved