Study on identification of Russula subnigricans by rDNA-ITS molecular barcode technique
FU Wusheng1,2,3,4,TANG Changdong1,LIN Feng1,4,CHEN Jingze1,2,SONG Tao1,FANG Qinmei5*
1.Fujian Center for Diseases Control and Prevention(Fujian Provincial Key
Laboratory of Zoonosis Research),Fuzhou,Fujian 350012,China;
2.School of Public Health,Fujian Medical University,Fuzhou,Fujian 350108,China;
3.School of Food Science,Fujian Agricultural and Forestry University, Fuzhou,Fujian 350000, China;
4.Fujian University of Traditional Chinese Medicine,Fuzhou,Fujian 350108,China;
5.Fujian Academy of Agricultural Sciences,Fuzhou,Fujian 350003,China
Abstract:Objective To develop a reliable ITS(internal transcribed spacer)sequencing method to identify food poisoning incident caused by toxic mushroom(Russula subnigricans). Methods DNA extracted from the mushroom powder was amplified by PCR technique, followed by ITS sequencing through cloning technology. The similarity was compared between the DNA sequences of the sample and from GenBank in NCBI database with BLAST (Basic Local Alignment Search Tool) and the phylogenetic tree was built for further analysis. Some factors such as DNA concentration, sampling site and cooking influence were also evaluated. Results The similarity was more than 99% between the DNA sequences of the poisoning sample (R02) and the DNA sequences of seven kinds of toxic mushroom (Russula subnigricans) subgroups from GenBank, and all the DNA sequences belonged to the same branch, which showed that the poisoning sample and the corresponding species belonged to the same species. Coupled with morphological identification,the sample R02 was identified as Russula subnigricans. The other two samples did not belong to Russula subnigricans. Conclusion The results showed that the rDNA-ITS molecular barcode technique was successfully developed to identify the toxic mushroom,such as Russula subnigricans, and will be an effective identification method for food poisonings caused by mushroom.