Antioxidant activity of ripe and unripe pepino fruit (Solanum muricatum Aiton).
Ripe and unripe exotic pepino fruit were evaluated for antioxidant activity, total phenols, and flavonoid content. The antioxidant potency was investigated by employing various established in vitro systems, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2-2'-azinobis(3-ethylbenthiazoline-6-sulphonic acid (ABTS), hydroxyl radical scavenging, reducing power, ferrous ion chelation, ferric reducing antioxidant power (FRAP), and lipid peroxidation. The EC(50) values of ripe ethanolic extract on DPPH radical, reducing power, ferrous ion chelation, ABTS radical, FRAP, hydroxyl radical, lipid peroxidation (brain), and lipid peroxidation (liver) were obtained to be 2.20, 2.81, <5.00, 34.06, 8.53, 1.30, 1.75, and 0.51 mg/mL, respectively. However, the EC(50) values for unripe fruit extract were noted to be 3.75, 3.40, 11.25, 40.12, 9.75, 0.80, 1.91, and 0.63 mg/mL, respectively. Ripe fruit exhibited the highest values of antioxidant activity in all the scavenging assays except for hydroxyl radical scavenging assay. Ripe pepino had higher total phenol and flavonoid content than unripe fruit. This study suggests that possible mechanism of the biological activities may be due to free radical scavenging and antioxidant characteristics, which may be due to the presence of polyphenols in the fruit extracts.


CONCLUSIONS
The ripe and unripe pepino fruit have excellent antioxidant properties, so the results obtained in this study clearly indicate that pepino fruit has a significant potential to use as a natural antioxidant agent and possibly as a food supplement.
Department of Biochemistry, Kongunadu Arts and Science College, Coimbatore 641 029, Tamil Nadu, India. vadivusasi16@gmail.com
Govindan
G
Sudha
Marimuthu Sangeetha
MS
Priya
Rajan Babu Indhu
RB
Shree
Sabapathy
S
Vadivukkarasi
D000818:Animals; D000975:Antioxidants / Q000032:analysis* / Q000494:pharmacology; D052160:Benzothiazoles / Q000032:analysis; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000032:analysis / Q000494:pharmacology; D005638:Fruit / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000032:analysis / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D010936:Plant Extracts / Q000032:analysis* / Q000494:pharmacology; D059808:Polyphenols / Q000032:analysis / Q000494:pharmacology; D051381:Rats; D032322:Solanum / Q000737:chemistry*; D013451:Sulfonic Acids / Q000032:analysis
D000975:Antioxidants; D052160:Benzothiazoles; D005419:Flavonoids; D010936:Plant Extracts; D059808:Polyphenols; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D017665:Hydroxyl Radical