| Patulin is a neurotoxicological metabolity from fungi, which has potential carcinogenicity and mutagenicity. The major dietary exposure of humans to patulin is from the consumption of apple and apple juice contaminated by molds. Patulin is the most stable in apple juice, and is one of the important quality criteria for apple juice safety. It has been paid great universal attention. Ergosterol is a sort of alcohols compounds mainly located on the fungi cell membrane, which can be used for characterization fungal biomass, it has been becoming one of the most important tumor markers of fungal biomass. So, study on the accuracy and fast method for the determination of patulin, ergosterol and their relativity in apple juice has extremely important science meaning and industry application prospects for the exact valuation of apple juice safety.In this paper, SPE-HPLC and LLE-HPLC methods were adopted to extract and detect patulin in apple juice, and the competitive experiments about recoveries and precisions of the two kinds of methods were discussed, and the optimal extraction and detection method and conditions were optimized. In addition, according to the optimization of ergosterol extraction conditions, the reasonable conditions of ergosterol extraction were gained. After that, according to the research of relativity of ergosterol and patulin in apple juice, the quantitative mathematical model was built. The theoretical basis was established for patulin detection and evaluation according to the ergosterol detection and evaluation in apple juice. The main results were as follows:1. SPE and LLE the two kinds of sample pre-processing methods were used for the patulin cleaning and enrichment in apple juice concentrate, then the detection method HPLC was used for analyzing the content of patulin in samples after proposing. Results show that the recoveries of C18-SPE, HLB-SPE and LLE were respectively: 87.56%～88.40%, 85.45%～88.12%, 79.47%～80.10%, and the coefficient variations were respectively: 3.28%～4.47%, 4.32%～7.15%, 6.28%～7.67%. The recovery of C18-SPE-HPLC method was as high as 88%. The proposed method has higher recovery and precision and the reasonable reproductivity, RSD≤5%.2. According to the further optimization of C18-SPE-HPLC detection conditions, results show that when the sample size was 5.0g and the grads eluent were 6mL methanoL, 8mL methylene chloride with 10% methanol, 6mL ethyl acetate, the recovery of C18-SPE method was 88.70%～91.56%, and coefficient variation was 3.06%～4.03%.3. Through using the experimental design software-Design expert and the analysis of RSM, the quadratic multiterm mathematical model of ergosterol extraction in raw apple juice was founded, mathematical model is correct by analyzing. In the meantime, make use of the response surface plot and its contour plot to discuss the saponification factors which influence the result of ergosterol extraction and its interaction and then the optimal saponification conditions were: saponification time 65.7min, saponification temperature 93.93℃, Alcohols use level: 79.9mL methanol and 45.1mL ethanol, and KOH 10.12g.4. Study for the content correlation of patulin and ergosterol in different batches raw apple juice samples, the quantitative mathematical model between patulin and ergosterol was achieved, and the regression equation was y=-0.0384x+3.2215, correlation coefficient was 0.9432, of which, x was the patulin content in apple juice(μg/L) and y was the ergosterol content(mg/L).
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