Comparative study of antioxidant compositions of <i>Ocimum gratissimum </i>(African Basil), <i>Ocimum africanum </i>(lemon basil), <i>Zingiber officinale</i> (ginger) and <i>Curcuma longa </i>(turmeric)

Abstract

Background: Natural antioxidants are abundant in many herbs and spices in Nigeria. Knowledge of their antioxidant contents will promote decision to make these herbs and spices part of one's daily diet which is vital for optimal health.

Objectives: Comparative analysis of antioxidants (phospholipids, phenolic compounds, ascorbic acid and carotenoids) contents of some common herbs and spices (African basil, lemon basil, ginger and turmeric) in Nigeria was carried out.

Methods: Triplicate determinations of the value of each of the antioxidants in the samples were done using standard methods. The results were analyzed using the Statistical Package for Service Solution (SPSS) version 22. Means and standard deviations were analyzed. Duncan's new multiple range test was used to separate the means, and analysis of variance was used to compare the means. Significance was judged at p<0.05. Pearson's correlation coefficient was used to determine correlation between antioxidant contents of the herbs and spices

Results: African basil had the highest phenolic compound content (156 mg/100 g), while ginger had the lowest content (17 mg/100g). The carotenoids content was highest (23.91 mg/100g) in African basil and lowest (1.56 mg/100g) in ginger. The ascorbic acid values of the samples ranged from 2.13mg/100g in African basil to 337 mg/100g in ginger. The phospholipid values of the samples ranged from 2.37 mg/100g in ginger to 11.13 mg/100g in turmeric.

Conclusion: African basil is a better source of phenolic compounds and carotenoids; ginger is a richer source of ascorbic acid, and turmeric is a richer source of phospholipids. Incorporating these herbs and spices in diets is vital for optimal health; hence, creation of awareness on their health benefits through nutrition education is recommended.