Identification of Monascus pigments and citrinin in Sufu using a novel HPLC-MS/MS method

Abstract

Sufu is the traditional fermented soybean products in China. The aim of this study was to establish a rapid and sensitive method for the determination of 3 monascus pigments and citrinin in sufu, assess the content of them in sufu samples obtained from market. The extracted sufu samples were purified by optimized SPE methods: discard the first 1 mL of effluent and collect the rest for HPLC-MS/MS determination. Good linearities were obtained (r > 0.999) in the range of 0.05–10 μg L−1 for citrinin, monascin and monascorubramin, and 0.05–10 mg L−1 for monascorubrin. The method has been successfully applied to the identification of monascus pigments and citrinin in sufu samples, and the Spearman correlation analysis of the concentration was also performed, therefore fulfilling the requirements for mycotoxins analysis. Besides, according to the health risk assessment of citrinin, the health risk caused by intake of sufu was not significant, and the recommended safe sufu consumption rate was 211.0 g person−1 day−1. The established method was fast, sensitive and accurate, was suitable for the analysis of 3 monascus pigments and citrinin in sufu.