Study On The Determination Of Ellagic Acid And Vitamin C In Blackberry Juice By Hplc

The blackberry is an edible fruit produced by Rubus fruticosus, or any of several hybrids between that species and others of the Rubus genus in the Rosaceae family. Blackberries have a high abundance of healthy antioxidants and nutrients such as anthocyanins, salicylic acid and ellagic acid, which can remove free radical in human body, regulate body metabolism, eliminate fatigue, delay senility and improve immunity. Blackberries are also low in calories, carbohydrates, and fat, making them one of the best fruits out there for a balanced diet.Blackberry juice is the deep processed products of blackberries. Health Components such as ellagic acid, anthocyanins, vitamins, minerals and superoxide dismutase may be destroyed during the product manufacture, transport, and storage. During the manufacturing procedure, furthermore, sometimes other substances was added into the juice to improve the taste and extend the storage time.In present work, a new method for the determination of Ellagic acid and Vitamin C in blackberry juice was developed. And it was applicated in marketing products quality inspection. The mainly points are as follows:1. An HPLC method was established for the determination of ellagic acid in blackberry juice. Lichrospher C18 column (150 mm ×4.6 mm,5μm) was used and the column temperature was set at 35℃. Ammonium acetate buffer (5mmol/L, pH3.0)-methanol (55:45) was used as mobile phase. A UV detector was used and the determination wavelength was set to 254nm. The external standard method was used for the content testing of ellagic acid under the chromatography conditions:There was good linearity betweent he peak area and the content of ellagic acid in t he range of 5-30μg/mL (r= 0.9995). Precision RSD was 1.06%; the reproducibility RSD was 1.15%; the r in the stability-testing of 8 hour was 0.9957, the RSD in the stability-testing of 2 hour was 1.704%; the average recovery of sample was 99.63%(RSD:0.75%). And finally, the content of ellagic acid measured was up to 14.12μg/mL.2. An HPLC for the determination of vitamin C in blackberry juice was established. The method was simple and accurate for the determination of total ascorbic acid in blackberry juice. The method was developed with the condition as follows:Amino column (4.6mm×150mm,5μm), pH3.5 phosphate buffer:acetonitrile= 30:70 as the mobile phase with the speed of 1.0 ml/min. Total VC was detected after DTT reduction. This method is simple, accurate, feasible for determination of total VC of blackberry pulp fruit juice.The present work established methods for the determination of ellagic acid and total vitamin C in black berry juice. This provided information for the study of health components in blackberry juice and the optimization of producing process and the quality control of blackberry juice.