Comparative Screening of Phytochemical and Proximate Constituents of Leaf, Stem and Root of Oldenlandia corymbosa L. and Oldenlandia herbacea (L.) Roxb

Abstract

Introduction: Oldenlandia corymbosa L. and O. herbacea (L.) Roxb. are species of the genus Oldenlandia in the family Rubiaceae. They are common weeds found in temperate and tropical regions of Africa and Asia. Methods: Phytochemical and proximate evaluation of the leaf, stem and root of Oldenlandia corymbosa L. and O. herbacea (L.) Roxb. were carried out with standard analytical methods, in order to assess the potentials of the plants' parts. Results: Greatest percentage of alkaloid at 1.72 ± 0.00, anthraquinone at 2.78 ± 0.03 and tannin at 3.16 ± 0.24 were found in the leaf of O. corymbosa while highest level of flavonoid at 1.32 ± 0.00% was present in the leaf of O. herbacea. Highest concentration of crude protein at 13.87 ± 0.04% was detected in the leaf of O. corymbosa. Level of fat was relatively the lowest in all parts of both species. Greatest level of hydrogen cyanide was found in the leaf of O. herbacea at 3.41 ± 0.01 mg/kg followed by the values in the leaf of O. corymbosa at 2.29 ± 0.01 mg/kg and stem of O. herbacea at 2.72 ± 0.00 mg/kg. The values were considered significantly different at P < 0.05. Conclusions: The active metabolites and nutritive components of O. corymbosa and O. herbacea have successfully been revealed in this work; hence the ethnobotanical usefulness as food and medicine is highly encouraged. However, precaution should be taken in the use of raw samples of leaf and stem of these Oldenlandia species. In addition, this study may also supply additional information that may be helpful in resolving the ongoing controversy in the placement of these species in the right genus.