Bioactive Compounds and Antioxidant Potential of Aqueous and Hydroethanolic Extracts of Cola lateritia Fruit Parts

Generalities: Cola lateritia (C. lateritia) is an under-valorized (neglected and unutilized) plant traditionally used in certain Cameroonian villages as medicine to manage certain diseases. The present work aimed to assess the phytochemical composition and the antioxidant potential of different parts of C. lateritia fruits. Methods: The fresh fruits of C. lateritia were purchased in October 2022 at Mfoundi-Market (Yaoundé 5, Centre Region of Cameroon), washed, sliced, dried, and powdered before being extracted with distilled water for the aqueous extract (AE) and ethanol/distilled water (70:30, v/v) for the hydro ethanolic extract (HEE). The bioactive compounds (polyphenols, saponins, tannins, flavonoids, and alkaloids) of the different extracts of fruit were quantified using standard methods. The Antioxidant potential of the different extracts was assessed using various methods [scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, Total Antioxidant Capacity (TAC), and Ferric Reducing Antioxidant Power (FRAP)]. Results: The results indicated that the different extracts of C. lateritia fruit contain phytochemicals [polyphenols, flavonoids, tannins, saponins and alkaloids]. The AE of the skin (AE-sCLf) presented the highest contents (590.33 µg CaE/g DM, 191.73 µg QE/g DM and 945.33 µg  SaE/g DM) for polyphenols, flavonoids and saponins respectively while, the AE of pulp  (AE-PCLf) showed the highest content in alkaloids (121.59 µg QiE/g DM). The lowest tannin content was also reported in the AE of pulp (2.02 µg CaE/g DM). The extracts of C. lateritia exhibited a good radical scavenging activity of DPPH (with an inhibition percentage of 74.084 and 69.40% respectively for HEE-SCLf and AE-sCLf at 4 mg/mL). It’s reducing power towards molybdate and iron was concentration-dependent with values ranging from 0.116 to 2.393 μg AAE/g DM for TAC and from 0.0015 to 0.0032 μg AAE/g DM for FRAP, respectively. The highest iron-reducing activity of 941.410 µg AAE/g DM was observed with AE-sCLf at 4 mg/mL. The principal component analysis (PCA) showed a strong positive correlation between Bioactive and antioxidant activities. Conclusion: The C. lateritia fruit extracts (AE and HEE) contain various bioactive compounds, which exhibit good antioxidant activities through different mechanisms. It suggests C. lateritia as a potential nutritious food as well as functional food useful for the prevention of management of cardiometabolic diseases.