Study On Sweet Potato DHEA Detection System And Factors Affecting The Content

Sweet potato which is rich in nutrient is good for human health. It is an important food, feed and industrial crop. DHEA is the precursor of human body's synthesis of a variety of hormones, known as "the mother of hormones". It has function of anti-cancer, anti-aging and enhancing immunity etc. The sweet potato DHEA detection system were established. The different genotypes, growth stages, location, potato color of sweet potato DHEA content were studied. The results were as follows:1. Sweet potato DHEA detection system was established and optimizedUsing the standard DHEA, according to the impact of Chromatographic conditions, the concentration gradient preparation different standard solution, and selecting the best Chromatographic conditions: the wavelength was 215 nm, and the mobile phase was methanol: water as eluent (7:3, v/v), mobile phase flow rate of 0.8 ml / min, the temperature was 35℃. The sweet potato extraction system was optimized with the determination system. Four orthogonal factors and three levels experiments were designed with SP4 materials. The best extraction conditions were as follow: ultrasound for 60 minutes, solid/liquid 1:3, the number of dichloromethane extracts of three times and the number for the water four times.2. Factors Affecting Sweet Potato DHEA(1) Sweet potato DHEA levels have a significant impact on different genotypes. The 205 different varieties of sweet potato genotypes of DHEA level were detected.The results showed that the different varieties of sweet potato genotypes about DHEA levels were significantly different. The highest content DHEA sweet potato variety was SP1, whose content was 752.98 ug/100g, 2.55 times of the control Jinshan57. SP246 was selected from the eight other sweet potatoes whose leave were as vegetables. It's DHEA content was the highest, whose content was 3.59ug/100g. The highest levels of DHEA in the petiole for the SP244, whose content was 2.28ug/100g ,was 1.81 times of control Fushu7-6.(2) Sweet potato different stages had influenced DHEA levels. The experimental results showed that sweet potato DHEA levels in skins and meat in the late growing period were significantly higher than the medium -term period. In the potato meat, fertility late was in the medium-term 1.81 times, and in potato skins, the latter part of DHEA was in the earlier period of 7.77 times. (3) The content of sweet potato DHEA in different parts had significant different. The experimental results showed that the level of DHEA was in the following order: potato skins (the average of 126.03 ug/100g), potato meat (the average of 16.23 ug/100g), leaves (the average of 5.74 ug/100g), petiole (the average of 2.55 ug/100g).(4) DHEA in the different color the tubers of sweet potatoes including purple, red, yellow and white and so on were determined. We found there was no obvious correlation between DHEA content and color.