Flavonoid-to-Phenol Ratios in Methanolic Extracts of Aspilia africana: Implications for Managing Oxidative Stress
Owo, Gogo James *
Department of Biology, Faculty of Natural and Applied Sciences, Ignatius Ajuru University of Education, Rumuolumeni, Port Harcourt, Rivers State, Nigeria.
Karibo, Amakiri Okari
Department of Medical Biochemistry, Faculty of Basic Medical Sciences, College of Medical Sciences, Rivers State University, Nkpolu-Oroworukwo, Port Harcourt, Rivers State, Nigeria.
Kpomah Enyowho Dennis
Department of Biochemistry, Faculty of Sciences, Federal University, Otuoke, Bayelsa State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Oxidative stress results from the imbalance between the production and regulation of reactive oxygen species or free radicals and causes harmful effects such as cancer, Alzheimer’s disease, cardiac diseases, kidney disorders, liver diseases, fibrosis, atherosclerosis, arthritis, neurodegenerative disorders, aging and so on. Plant phenolics and flavonoids play a significant role in scavenging free radicals in the body and act as antioxidants. This study aimed to quantify the total phenolic and flavonoid contents in different parts of Aspilia africana and evaluate their potential antioxidative properties through flavonoid-to-phenol (F/P) ratios. Total phenolic and flavonoid contents of the extracts of Aspilia africana were determined using spectrophotometric methods. The results obtained showed that the highest total phenolic content value was observed for the roots extracts (150.75 ± 0.11 mg GAE/g) followed by the leaves extracts (112.17 ± 1.62 mg GAE/g), and the lowest was for the stems extracts (98.34 ± 0.19 mg GAE/g). The high phenolic content of the root (150.75 ± 0.11 mg GAE/g) indicates that the root of A. africana may have a high antioxidant capacity. The leaf of A. africana had the highest total flavonoid content while the stem had the lowest total flavonoid content. This is an indication that the methanolic root extract has antioxidative potential. The F/P ratio ranges from 1.17 to 2.51, with the leaf extract having the highest flavonoid/phenolic ratio of 2.51 and the root extract having the lowest flavonoid/phenolic ratio of 1.17. The high F/P ratio of the leaves extract shows that it contains more flavonoids than the stems and roots. Hence, the leaf extracts of A. africana, with their elevated flavonoid content, could be used in developing dietary supplements or therapeutic formulations aimed at managing oxidative stress and enhancing overall health. This practical application of the study’s findings underscores the importance of harnessing natural sources of antioxidants. Most importantly, the study points to the need for further research to elucidate the specific mechanisms through which flavonoids and phenolics exert their antioxidant effects. Such research could help optimize the use of A. africana extracts in managing oxidative stress and improving health outcomes related to oxidative damage.
Keywords: Total phenolic, total flavonoid, Aspilia africana, oxidative stress, antioxidant