Determination Of Antioxidant Activity And Vitamin C Content Of Mango (mangifera Indica L.) And Pineapple (ananas Comosus) Fruit Juice

Background: Mangoes and pineapples are popular fruits and are widely consumed in Nigeria as food or snack but local data on their antioxidant value is scarce.Objective: The aim of this study was to determine the antioxidant activity and Vitamin C content of the juice of locally available mango and pineapple fruits in Lagos, Nigeria.Methods: Two varieties each of mango (Haden and Alphonso) and pineapple (Cayenne and Sarawak) fruits were sourced from local markets. Fresh juice of the ripe fruits was extracted and analyzed for phytochemical components such as tannins, reducing sugars,carbohydrates, terpenoids, steroids, glycosides, proteins, alkaloids, flavonoids and saponins. The Vitamin C content of the juice was determined using high performance liquid chromatography (HPLC) method. The antioxidant activity was assessed in vitro by determination of free radical scavenging activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The ferric reducing power and total phenolic compounds were also determined.Results: The Vitamin C content in mg/100 g sample was 28 for the Haden variety and 88 for the Alphonso variety of mango. The Cayenne variety of pineapple had Vitamin C content 63 mg/100 g which was higher than in the Sarawak variety (14 mg/100 g sample). Free radical scavenging activity and total phenolic compounds were highest in the Cayenne variety of pineapple while Alphonso variety of mango had the highest ferric reducing power.Conclusion: The mangoes and pineapples studied possess antioxidant activity in terms of free radical scavenging activity (38 to 48 µg/ml Ascorbic acid equivalent) and ferric reducing power. They also contain Vitamin C, phenolic compounds and phytochemicals ofnutritional value