The Analysis Study On Nutrition Constituent In Pumpkin Seed

Pumpkin seed is a kind of health food and the main medicinal ingredients iscucurbitin,which shows the effects of desinsectization, falling blood pressure,anti-inflammatory. In this thesis,the contents of mineral elements in pumpkin seedwere determinated and extraction conditions of pumpkin seed oil、cucurbitin andtryptophan was optimized. The determination of cucurbitin was studied by UV-visiblespectroscopy and high performance liquid chromatography,and that of tryptophan wasstudied by fluorescence spectrometry. Some results were obtained as the followings:The contents of twleve kinds of elements in pumpkin seed such as Ca、P、K、Na、Mg、Fe、Se、Mn、Zn、Sn、Cu、Al were determinated by ICP-AES, and itsrecoveries were 95.48%～103.2% with relative standard deviation of 3 55%. Rawpumpkin seed contained abundance of P, K, Mg elements, and the content of Ca, Sn,Fe was higher.By frying, the content of Se、Cu、Al reduced to zero and that of P lostgreat,but other elements were influenced less. It did not affect the intake of themineral element to eatting edible craft pumpkin seed comparing to eatting rawpumpkin seeds.The effects of the extraction conditions to oil extraction efficiency by comparingthree kinds of extraction methods such as Soxhelt extraction method, solventextraction method and ultrasonic extraction method were studied.The optimizedconditions were as: rate of material to solvent was 1:20, extraction solvent was hexane,Ultrasonic power was 200w and Ultrasonic time was 1.5h.The oil extractionefficiency was 49.95% on the optimized conditions.The optimized extraction conditions of cucurbitin were as: extraction solvent was4% dilute hydrochloric acid, rate of material to solvent was 1:20, Ultrasonic powerwas 200w and Ultrasonic time was 75min. The determination of cucurbitin wasstudied by UV-visible spectroscopy. The absorbency increased with the increase ofthe concentration of cucurbitin with linear within 150μg·mL^-1. Its recoveries were97.51%～103.8% with relative standard deviation of 1.64%.The average contents ofcucurbitin in medical pumpkin seed was obtained as 45.32mg·g^-1. The determinationof cucurbitin was also studied by high performance liquid chromatography. The peak area increased with the increase of the concentration of cucurbitin with linear within160μg·mL^-1. Its recoveries were 96.50%～102.1% with relative standard deviation of1.08%.The average contents of cucurbitin in medical pumpkin seed was obtained as46.21mg·g^-1.The determination results conformed basically by these two methods.The extraction conditions of tryptophane were as: the concentration of Sodiumhydroxide was 5.5mol·L^-1and pH of buffer solution was 10.5. The determination oftryptophane was studied by fluorescence spectrometry. The fluorescence intensityincreased with the increase of the concentration of tryptophane with linear within140μg·mL^-1. Its recoveries were 96.91%～102.2% with relative standard deviation of0.52%.The average contents of cucurbitin in medicine pumpkin seed was obtained as5.56mg·g^-1.