**1. Introduction**

Traditional medicines composed of plants and their extracts used to cure various infections and ailments are being modified and refined to modern formulations in order to play a significant role in the treatment of various diseases such as diabetes, ischemic heart diseases, atherosclerosis and the initiation of carcinogenesis or liver diseases [1,2]. The physiological response imparted by the phytochemicals induces the desired therapeutic action [3,4]. The most essential of these bioactive constituents are phenolic compounds, alkaloids, saponins, tannins and flavonoids. *Cucurbits* form an important and large fruit crop set, cultivated extensively in subtropical and tropical countries, and contains a terpenoid substance known as Cucurbitacin [5]. The whole fruit of *Cucumis melo* L. (*C. melo* or muskmelon) is indicated for chronic eczema and to treat light burns and scrapes [6].

Dose-dependent cytotoxic activities exhibited by an aqueous fruit extract of *C. melo* in human prostate carcinoma PC 3 cell lines is evidence of its anti-cancer property [7]. High superoxide dismutase activity (SOD) is responsible for the in vitro and in vivo antioxidant

**Citation:** Rajasree, R.S.; Ittiyavirah, S.P.; Naseef, P.P.; Kuruniyan, M.S.; Anisree, G.S.; Elayadeth-Meethal, M. An Evaluation of the Antioxidant Activity of a Methanolic Extract of *Cucumis melo* L. Fruit (F1 Hybrid). *Separations* **2021**, *8*, 123. https:// doi.org/10.3390/separations8080123

Academic Editor: Didier Thiébaut

Received: 27 July 2021 Accepted: 13 August 2021 Published: 18 August 2021

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and anti-inflammatory properties of their extract [8]. The in vitro evaluation of the antioxidant properties of *C. melo* leaves and fruit extracts reported concentration-dependent scavenging activity. 1,1-diphenyl-2-picrylhydrazyl (DPPH) was employed as the free radical in the evaluation of the reducing substances [9]. Previous investigations suggested that *C. melo* is a potential source of natural antioxidants and can act as a therapeutic agent in preventing oxidative stress-related disorders [10–12]. Advanced techniques using supercritical and subcritical CO2 are also recommended to improve the bioavailability of the active ingredients [13]. In the present study, the antioxidant activity of a methanolic extract of *C. melo* fruit (F1 hybrid) was evaluated using standard procedures.
