| Pumpkin seed has plenty of nutritional ingredients and physiologically active substance, for example protein and fatty acid which supply some medicinal values for people health. The seed shape, nutrient contents were studied for the seventeen pumpkin seed varieties which were composed of Cucurbit pepo L.,Cucurbit maxima Duch,Cucurbit moschata Duch, Cucurbit ficifolia Bouche. The extraction technical of pumpkin seed oil and the separation purification of Unsaturated fatty acid were optimized.The shape was compared by seventeen pumpkin seeds, results showed that the length, width and 1000-seed weight of Cucurbit maxima Duch were higher than Cucurbit pepo Land Cucurbit moschata Duch. The correlate analysis showed that the length and width of pumpkin seeds were positively correlated with 1000-seed weight, but non-correlated with rate of kernel. The pumpkin seed microstructure showed that some thin cell composed of pumpkin seed, the size was different. The cell group which was composed by oil cells was in the middle of the seed.The seventeen pumpkin seed varieties were determined for main nutrient contents. The solid content ranged from 94.59-96.19%. The content of protein ranged from 31.47~ 44.24g/100g·FW, fibre ranged from 3.82~13.94g/100g·FW, soluble sugar ranged from 49.11~ 80.23mg/100g·FW, amylum ranged from 0.013~0.019mg/100g·FW, The seed fatty acid ranged from 14.47~20.20g/100g·FW, K content were higher than Na content, P and Mg content were higher than others, microelement contents were more.The extraction technical of pumpkin seed oil was optimized, used light petroleum(30-60℃), through the improved Soxhlet extractor method, the time was 12 hours, can obtain more pumpkin seed oils.The extraction rates of Jinhui2 and Heizi reached to 48.40% and 50.83%. The composition of fatty acid in the seed oils were analysed by GC. The pumpkin seed oils consisted mainly of linoleic acid, oleic acid and palmitic acid. The result show that The content of palmitic acid ranged from 3.84~7.74g/100g·FW, oleic acid ranged from 6.42~18.10 g/100g·FW, linoleic acid ranged from 7.46~24.38g/100g·FW. The Jinhui2 has highest linoleic acid content which was 24.38g/100g·FW.Unsaturated fatty acids were separated and purified from the seed oil of Urea clathration. The result showed that the purity of linoleic acid have more relation of the proportion of fatty acid. Urea and ethanol, but the time and temperature influenced less. When the fatty acid to Urea was 1: 2.5 ,Urea to ethanol was 1: 2, after storage of 20 hours at 10℃, The purity of linoleic acid increased from 62.82% to 95.79%.The study of nutritional ingredients in pumpkin seed varieties was affluent in food component database and offered theoretical basis for pumpkin quality improvement. In addition, the optimize of The distill technical of pumpkin seed oil and the separation purification of Unsaturated fatty acid, offer the database for the pumpkin seed oilproduction in industry, and it will enrich the kinds of edible oil, changed the consumption structural of edible oil in China.
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