Variability of vitamin E content in pumpkin seeds (Cucurbita pepo L.)

Pumpkin (Cucurbita pepo L.) seed oil is a common salad oil which is produced in the southern parts of Austria, Slovenia and Hungary. It is dark green and has a high content of free fatty acids. Due to its colour, the oil cannot be used for cooking. The content of vitamin E, especially gamma-tocopherol, is very high. The oil content of the pumpkin seed is about 50%. The seed itself can be eaten. Therefore a pumpkin variety with high vitamin E content is desirable. The aim of this work was to find a variety of Cucurbita pepo which has a high oil yield and a high vitamin E content. A total of 100 breeding lines were tested for their tocopherol content. The tocopherols and tocotrienols are extracted with hexane and analysed by NP-HPLC/FLD with hexane/dioxan (96/4) as eluent, with fluorescence detection at 292/335 nm. The gamma-tocopherol content, which is about 5-10 times as much as that of alpha-tocopherol varies over a broad range (41-620 mg/kg dry pumpkin seeds). Beta- and delta-tocopherol are found at low levels.