In vitro Biological activities of aqueous extracts of Tetrapleura tetraptera (Schumach & Thonn.) taub. and Aframomum citratum (C. Pereira) K.Schum from three Agroecologic zones in Cameroon

anglais. peer reviewed

anglais. Study some phytochemical constituents and biological activities of twelve samples of Tetrapleura tetraptera (Schumach & Thonn.) taub. and nine of Aframomum citratum (C. Pereira) K.Schum fruits collected in three Agroecologic zones in Cameroon: Bimodal forest zone (ZONE V), Unimodal forest zone (ZONE IV) and highlands zone (ZONE III). Methods: Fresh fruits extracts were obtained by aqueous infusion (100°C/15min) and evaluated by spectrophotometric methods for total polyphenol (TPP), total flavonoids (TFLV) contents and antioxidant (DPPH, Total Antioxidant Capacity by the Phosphomolybdenum method or TAC, Iron reducing power or FRAP and inhibition of linoleic acid peroxidation or B.CAROT assays) and anti-inflammatory (Inhibitions of Protein denaturation and 5-LOX activity respectively INH.PROT and INH.5-LOX) properties. Principal Component Analysis providing a transparent view of information was performed. Results: T. tetraptera has the highest levels of TPP, TFLV and biological activities. For both species, fruits from ZONE V have the most important TPP, TFLV levels and biological activities. TPP and TFLV content of A. citratum and T. tetraptera fruits are positively and significantly (p<0.05) correlated. All extracts biological activities (0.25, 2.5, 25, 250 mg/mL) are dose-dependent and they have shown strong antioxidant and anti-inflammatory activities, but less than references (Ascorbic Acid, Diclofenac, Quercetin, and Butylated Hydroxytoluene). There is a positive correlation between TPP, TFLV and TAC, FRAP, B.CAROT assays and inverse correlations are observed with the IC50 (g/mL) of DPPH, INH.5-LOX and INH.PROT assays for both species. Conclusion: The fruits reveal their variabilities and those from ZONE V for both species are economically and healthcare challenging for herbalists, pharmaceutical firms, scientists and consumers. Indeed, most important extraction yield of bioactive compounds correlated with significant biological activities and the use of less material compare to an implementation in others AEZ with the same results are noted.