[Determination of 2-acetyl-1-pyrroline in aroma rice using gas chromatography-mass spectrometry]

A gas chromatography-mass spectrometry method was developed for the determination of 2-acetyl-1-pyrroline in aroma rice. 2,4,6-Trimethylpyridine (TMP) was added into the sample of aroma rice as internal standard, and the compound was extracted by the mixture of anhydrous ethyl alcohol and methylene chloride (1: 1, v/v) at 80 degrees C for 3 h under sealed condition in water bath. The effects of the temperature and time on the extraction were investigated. The analyte was separated and determined using gas chromatography-mass spectrometry on an HP-5MS capillary column (30 m x 0.25 mm x 0.25 microm) in scan monitoring mode. Calculated as 2,4, 6-trimethylpyridine, the average recovery of the method was 82.57% with the relative standard deviation of 5.09%, and the detection limit of method was 0.01 mg/kg. The method was employed for the determination of 2-acetyl-1-pyrroline in 11 aroma rice breeding varieties. The results showed that 2-acetyl-1-pyrroline was detected in 5 aroma rice varieties, including Qingxiangmi, Taixiang R207, Texmati, Guixiangsinuo and Zhongjian 2, with the contents of 0.097, 0.098, 0.699, 0.045 and 0.047 mg/kg, respectively. The method is simple, rapid and sensitive with low sample and reagent consumption. It is suitable for screening a lot of aroma rice varieties in breeding through the determination of 2-acetyl-1-pyrroline content.