Studies Preparation Of Procyanidines From Grape Seeds And Mycotoxins Determination

In this paper, procyanidines was preparation from grape seeds and mycotoxins was determinated by ultra-high-performance liquid chromatography-tandem mass spectrometry.Multi-stage countercurrent extraction (MCCE) technique has been developed for the extraction of proanthocaynidins from grape seeds. The effect of extraction was optimized using orthogonal array experimental in water and ethanol, respectively. The optimum process conditions by water were as follows:four stages,40 min extracting time for every stage,100℃temperature and 3 mL g-1 solvent to grape seed ratio. The optimum process condition by ethanol were as follows:coarse powder of grape seeds, ethanol-water (55/45, v/v),30 min extracting time for every stage,75℃temperature and 6 mL g-1 solvent to grape seed ratio. Under those conditions, the extraction efficiency of MCCE has been compared with single pot extraction, and the results showed that the MCCE process offers the higher proanthocaynidins extraction yield and considerable savings in time, energy and solvent consumption.The extract made by MCCE was purified by AB-8 resin, and the method was as follows:the solution in 8.28 mg mL-1 was added 4 BV into resin column in the speed of 2 BV h-1. Then,4 BV of water was added to wash away non-procyanidine in the speed of 4 BV h-1. According to production needs, there were two way to elute. (1) 20% ethanol eluted 4 BV in 2 BV h-1,and then 40% ethanol eluted 4 BV in 2 BV h-1. Two kinds of eluate were collected and vacuum dring respectively. (2) 40%ethanol eluted 4 BV in 2 BV h"1 directly, and the eluate was vacuum dring. The resin column was cleaned and reused.The purifying process of grape seed extracts was monitored using near infrared spectroscopy (NIRS). The samples in the purification process, which did not participate were used to test the performance of the models. The optimal calibration model was obtained with R20.9995, RMSEC 0.713, RMSEP 2.67, RSEC 2.39%and RSEP 8.48%in the 5500-6200 cm-1 spectral region when using Savitzky-Golay and second derivative spectral transform method. It was concluded that the proposed method is fast and nondestructive, and it provides a novel efficient and environmental friendly approach for the fast determination of the active components in macroporous adsorption resin purification process.Finally, grape seed and procyanidine were detected in mycotoxins. We made a method that simultaneous determination of AFB1, AFB2, MPA and STC in grape seed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) using l3C17-aflatoxin B1 as an internal standard. In this method, four mycotoxins could be separated in 4 min within good accurate, sensitive and reproducible. Then the method of determination of ochramycin A (OTA) in grape and procyanidine, which was analyzed by UHPLC-MS/MS using 13C20-OTA as internal standard. And the transformation of OTA in the process of extraction and purification were investigated. The results showed that the transfer of OTA in the extraction was in rate of 17.2%～25.6%an in the purification was in rate of 8.2%～10.7%.