Abstract:Purine compounds are important natural toxins in soybean, and excessive intake can induce hyperuricemia and gout. In order to reveal the levels of purine compounds in different soybeans, an ultrahigh-performance liquid chromatography (UPLC) method was developed for the determination of four purine compounds in soybeans, and the levels of guanine, adenine, xanthine, and hypoxanthine in 58 main planted soybeans in China were determined. The results showed that the method had good linearity (R2>0.9995) in the linear range (0.2~10 mg/L) and the detection limits were 0.0412~0.1001 mg/L. The precision RSD was less than 0.6000% and the RSD values for adenine, guanine, xanthine and hypoxanthine were 1.1103%, 1.0728%, 1.3762, and 0.9457% in that order. The recoveries of the four purine compounds spiked ranged from 92.5902% to -100.1373%. This paper also examines the comparative determination of the ideal extraction solvent (equal volume solution of trifluoroacetic acid and formic acid) and hydrolysis time (30 min). The data on the content of purine compounds in some of the main soybean varieties in China determined by applying this method showed that the purine content in different soybean varieties: high protein varieties > conventional varieties > high oil, protein, and lipid double-high varieties and the purine content in non-fishy soybean varieties differed significantly (2 013.06~2 824.54 mg/kg), and the findings of this study can provide scientific guidance for soybean processing and consumption.