Chemical Composition and Antioxidant Property of Two Species of Monkey Kola (Cola rostrata and Cola lepidota K. Schum) Extracts
Emmanuel E. Essien *
Department of Chemistry, University of Uyo, Akwa Ibom State, Nigeria
Nimmong- uwem S. Peter
Department of Chemistry, University of Uyo, Akwa Ibom State, Nigeria
Stella M. Akpan
Department of Chemistry, University of Uyo, Akwa Ibom State, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Aims: To determine the total phenols content and antioxidant activity of Cola rostrata and C. lepidota seeds and fruit pulp methanol extracts.
Study Design: In vitro evaluation of antioxidant assays; phytochemical screening, quantitative determination of total phenolics and flavonoids content of seeds and fruit pulp extracts.
Place and Duration of Study: Department of Chemistry, University of Uyo, Nigeria (July – October, 2014).
Methodology: Standard methods were employed in the phytochemical screening, quantitative phenols and flavonoid determination and antioxidant assays (DPPH radical, ferric reducing and metal chelating activity).
Results: Alkaloids, saponins, terpenoids, carbohydrates and flavonoids were detected in the seeds and fruit pulp extracts of the studied plants. Fruit pulp of C. rostrata and seeds of C. lepidota contained the highest amount of flavonoids (60.5 μgQE/g) and phenolics (72.9 μgGAE/g) respectively. The extracts exhibited significant DPPH radical and ferric reducing activity with IC50 values 50-66.5 μg/mL and 60.0-63.0 μg/mL respectively. The Cola extracts also demonstrated metal chelating activity (11.49-34.83%) at 100 μg/mL.
Conclusion: The results of this study substantiates a probable role of the seeds and edible fruit pulp of C. rostrata and C. lepidota as natural sources of antioxidants which could be further exploited for their potential biological activity.
Keywords: Sterculiaceae, Cola rostrata, Cola lepidota, antioxidant activity