Analysis and comparison of nutritional compositions in Yushu turnip(Brassica rapa L.)from different producing areas

Objective:To fully understand edible and commercial value,twelve batches of Yushu turnip in four different producing areas were selected to examine and comparison the nutrient composition. Methods:The β-sitosterol and total flavonoids were extracted with sub-critical fluid n-butane and 1,1,1,2-tetrafluoroethane(R134a),respectively. Then,the contents of β-sitosterol and total flavonoids were detected respectively. The contents of polysaccharides,soluble sugars,total saponins,amino acid,protein and various mineral elements were also detected. SPSS 19.0 was used to compare the contents of nutritional components of Yushu turnip from four different producing areas. Results:The contents of protein(2.20%),total amino acid(15.35%,calculated on dry weight)and total saponins(0.35%)were the highest in Qumalai county,the content of total sugars(2.90%)was the highest in Chengduo county,the contents of crude fiber(1.01%)and total mineral elements(447.5 mg/100 g)were the highest in Nangqian county. Conclusion:These figures indicate that Yushu turnips have high nutrients and practical applications,which to justify security controls.