A Comparative Analysis on the Antioxidant Activity and Anthocyanin content of Raphinus Sativus L and Beta vulgaris

Abstract

Introduction: :-Anthocyanins are natural pigments known for their antioxidant properties and potential health benefits. Antioxidants play a vital function to safeguard against oxidative stress (OS).This two vegetables having anthocyanin contents are reported to possess antioxidant properties. 

Objectives: This study conducted a comparative analysis on the antioxidant properties and  anthocyanin content, in two commonly consumed vegetables, Raphanus sativus L (red radish) and Beta vulgaris (beetroot), Anthocyanins were extracted by using a standardized (Std) method, and their profiles were determined using high-performance liquid chromatography (HPLC).

Methods: The antioxidant activities and anthocyanin contents of Raphinus sativus L and Beta vulgaris were evaluated by in vitro standard method by using spectroscopic Analysis. It was established what the antioxidant activities were by total antioxidant capacity, DPPH (1,1-diphenyl-2 picrylhydrazine) radical scavenging assay, hydroxyl radical scavenging assay, ferrous reducing antioxidant capacity and lipid peroxidation inhibition assay methods.

The pH-differential approach was utilized to ascertain the overall anthocyanin concentration. The process of maceration using ethanol acidified by concentrated HCl 0.5%, followed by liquid-liquid extraction using n-hexane, ethyl acetate, and water, allowed for the identification of anthocyanidin.

The purification of anthocyanin from water fraction was done with thin layer chromatography preparative using  Acetonitrile : methanol : water: glacial acetic acid (2:7:1:0.1) as eluent.

Results: The results revealed significant differences in the anthocyanin content and composition between the two vegetables. Raphanus sativus L exhibited a higher total anthocyanin content compared to Beta vulgaris. And these two samples were identified by U.V Spectroscopy & quantified by HPLC. The anthocyanin profiles varied, with Raphanus sativus L, containing primarily cyanidin-based anthocyanins, while Beta vulgaris contained a mix of betacyanin and betaxanthins. Identified quantity of anthocyanin in Beetroot samples was from 71.362 + 20 mg /Kg and for Red radish 146 + 19 mg / 100 g.

Raphanus sativus L, showed the highest antioxidant activity followed by beta Vulgaris DPPH and hydroxyl radical scavenging activity, the Raphanus sativus L was the most effective one with IC₅₀ 35.32 and 58.11 μg/mL, followed by Beta vulgaris with IC₅₀ 39.76 and 115.15 μg/mL, respectively. The Raphanus sativus L had the most potent inhibitory activity against lipid peroxidation with IC₅₀ 79.56 μg/mL. In addition, the reducing capacity on ferrous ion was in the following order: Raphanus sativus L > Beta vulgaris. The content of anthocyanin of Raphanus sativus L was found to be higher than Beta vulgaris.

Conclusions: The results indicate high correlation and regression (p-value <0 .001) between anthocyanin contents and antioxidant potentials of Raphinus sativus L and Beta vulgaris, hence the Raphinus sativus L and Beta vulgaris  could serve as effective free radical inhibitor or scavenger which may be a good candidate for pharmaceutical natural products. However, further exploration is necessary for effective use in both modern and traditional system of medicines.

These will help to understand the diversity of anthocyanins in different vegetables and it will help in the future for their potential health-promoting effects.