Evaluation of Selected in-vitro Biological Activities of the Seed Extracts of Ricinodendron heudelotii

Background and Objective: Plant crude extracts are analyzed to evaluate their potency as a starting material for preparation of eco-friendly and natural product-based drugs and substances for their potential therapeutic benefits. This study investigated the antileishmanial, anti-cancer, anti-inflammatory, cytotoxic and antibacterial activities of Ricinodendron heudelotii seed extracts. Materials and Methods: The seeds were collected, extracted and fractionated using hexane, DCM and ethyl acetate. The 96 microtitre plate bioassay, MTT HeLa cells, Brine shrimp assay and MABA assays were employed for antileishmanial, anti-cancer, anti-inflammatory and cytotoxicity activities of Ricinodendron heudelotii seed extract respectively. Results: The antileishmanial activity showed that all the extracts inhibited in vitro growth of Leishmania tropica promastigotes at the experimental dose with an IC₅₀ of 3.16, 3.49 and 3.34 μg/mL for hexane, ethyl acetate and DCM fractions, respectively. Hexane fraction showed the highest inhibition (60%) of ROS with IC₅₀of 32.4 The cytotoxic and in vitro anticancer activity of the extracts against human HeLa cervical cancer cell lines at 30 μg/mL showed that hexane, ethyl acetate and DCM fractions had 64.5, 59.9 and 15.6% cell growth inhibition, respectively. The cytotoxic activity using Brine shrimp (Artemia salina) lethality bioassay showed that hexane fraction had cytotoxicity at the highest concentration with LC₅₀ of 1548.82 antibacterial activity revealed that ethyl acetate fraction had a moderate inhibition against Staphylococcus aureus. Conclusion: This study revealed that Ricinodendron heudelotii seeds had in vitro antileishmanial, anti-cancer, anti-inflammatory, cytotoxic and antibacterial activities. The study thus provides evidence for the biological activities of Ricinodendron heudelotii seeds as the extracts showed varying potency levels for all investigated activities.