Screening of ten wild fruits extracts from Cameroon's flora for their anti-inflammatory and antioxidant potential

Background: Wild edible fruits are good source of phenolic compounds such as anthocyanins. Those compounds are known for their anti-inflammatory potential. They interact with many mediators of the physiopathological pathway such as NF-kB which is at a central position in the inflammatory response in macrophages. This study aimed to determine the anti-inflammatory and antioxidant potential of ten wild edible fruits aqueous extracts.

Methods: The antioxidant potential was evaluate through the DPPH, ABTS and OH radical scavenging activity; the ferric reducing agent power and the total antioxidant capacity assessment. Also, the total phenolic and flavonoids, anthocyanins compounds and vitamin C content were assayed. For the anti-inflammatory activity, a primary macrophage culture was used. Inflammatory mediators such as nitric oxide (NO), alkaline phosphatase, NADPH oxidase and 5-lipoxigenase activity was assayed.

Results: Alchornea cordifolia and Pentaclethra macrophylla extracts showed the greatest antioxidant activity respectively (Antiradical power (AP)=5.82 mol of DPPH/mg of extract and AP=5.05 mol of DPPH/mg of extract for DPPH scavenging assay); (IC₅₀=1.62µg/ml and IC₅₀=1.60µg/ml for ABTS radical scavenging assay); (IC₅₀=32.67µg/ml and IC₅₀=70.01µg/ml for OH radical scavenging assay) and (EC₅₀=54.06µg/ml and EC₅₀=17.46µg/ml for ferric reducing antioxidant power) with a non-significant difference with the reference compound. For the anti-inflammatory activity, firstly it has been observed that Alchornea cordifolia’s extract exhibits the greatest potential against NADPH oxidase activity inhibition (IC₅₀=36.20µg/ml); alkaline phosphatase activation (EC₅₀=0.27µg/ml) with non-significant difference with the reference compound. Secondly, Pentaclethra macrophylla’s extract demonstrated a high ability to inhibit NO production (IC₅₀=5.79µg/ml) and 5-lipoxigenase (IC₅₀=1.41µg/ml).

Conclusion: From the results obtained the assessed wild fruit extracts appears to be good sources for anti-inflammatory and antioxidant bioactive molecules. They could be beneficial for the research of new modulators for the management of inflammatory disorders.