Abstract
SPE-UHPLC-MS/MS was firstly used to evaluate the contamination of ochratoxin A (OTA) in Rasa roxburghii and firstly assessed the human exposure risk of OTA in Rasa roxburghii. A more suitable method for OTA extraction and purification of R. roxburghii was obtained, 25 mL of R. roxburghii juice was treated with enzymatic hydrolysis at a concentration of 0.06 mg/mL. The resulting mixture was filtered and concentrated to dry, then redissolved with 0.2 mL of methanol and diluted with 0.4 mL of ultra-pure water. The activated HLB column, which was added the sample solution, was washed with 6 mL of ultra-pure water and then eluted with 6 mL of methanol to purify. The eluent was collected and dried by nitrogen at 40 ℃, then redissolved in 1 mL of methanol and filtered for detection. The hazard quotient (HQ) values of all samples ranged from 0.077% to 35.792%, which were within the allowable limits for human consumption. But from the perspective of OTA contamination, we recommend the max stored time were 14 days at room temperature, 35 days at 4 ℃ and 63 days at -20 ℃ for R. roxburghii fruit, and 7 days for sealed storage and the same-day for open storage at room temperature, 14 days for sealed storage and 7 days for open storage at 4 ℃, and 63 days for sealed storage and 56 days for open storage at -20 ℃ for R. roxburghii juice. And all thirty samples randomly sampled from the market were OTA negative. The results of this study can lay a foundation for the formulation of OTA limit standards in fruits and juice in the future, and provide a reference for consumers to consume R. roxburghii more healthily.
