Influence of the fruit parts on bioactive compounds, antioxidant capacity, polyphenols, fatty acid and mineral contents of the pumpkin (Cucurbita maxima L.) fruits

Summary In the current work, the effect of pumpkin parts on the oil content, total phenol, flavonoid, carotenoid quantities, antioxidant capacity, phenolic components, fatty acid profiles and mineral profiles of pumpkin parts was investigated. Total carotenoid and phenolic amounts of pumpkin parts were recorded to be from 36.84 (seed) and 29.92 μg g−1 (pulp) to 28.75 (pulp) and 67.68 mgGAE/100 g (peel) respectively. Also, total flavonoid quantities of the parts of pumpkin were assigned between 21.07 mg/100 g (pulp) and 220.36 mg/100 g (seed), while antioxidant activities of pumpkin samples range from 0.04 mmol kg−1 (pulp) to 0.82 mmol kg−1 (seed). Catechin and caffeic acid amounts of pumpkin parts varied from 13.25 (seed) and 77.31 mg/100 g (peel) to 4.70 (seed) and 7.60 mg/100 g (peel) respectively. The amount of catechin detected in the pumpkin peel was approximately two and five times higher than the pulp part. Resveratrol content was lowest in the pulp part of the pumpkin. Oleic and linoleic acid values of the oils ranged from 19.23% (peel) to 29.16% (seed) and from 18.15% (peel) to 51.06% (seed) respectively. Stearic, oleic and linoleic acids of pumpkin pulp oil were higher than pumpkin peel oil. Pumpkin seed oils are rich in oleic and linoleic acids. P, K, Mg, S and Fe were the dominant biogenic minerals of pumpkin parts. The most of total carotenoids and total phenols were accumulated in the peel part of the pumpkin fruit. The total flavonoid quantity of pumpkin seeds was approximately three times higher than the pumpkin peel part and ten times higher than the pulp part. In this study, the changes in the oil yield, bioactive compositions (total phenol, total flavonoid and total carotenoid), antioxidant activity, phenolic component, fatty acids and mineral profiles of the parts considered as waste after processing were investigated.