米中椰毒假单胞菌酵米面亚种污染调查和风险分析

Pollution Investigation and Risk Analysis of Pseudomonas cocovenenans subsp.farinofermentans from Rice

调查湿米粉和湿粉条生产原料米中米酵菌酸和唐菖蒲伯克霍尔德氏菌(椰毒假单胞菌酵米面亚种)的污染状况,并模拟湿米粉和湿粉条产品环境,对菌株的产毒特性进行研究。在广东省的湿米粉和湿粉条生产企业及小作坊,共采集大米、碎米等原料米158份,其中45份样品检出米酵菌酸,含量范围是0.838~8.260μg/kg。筛选到5株具有唐菖蒲伯克霍尔德氏菌特征的可疑菌株,经产毒和分子生物学验证,确定均为唐菖蒲伯克霍尔德氏菌(椰毒假单胞菌酵米面亚种)。5株菌的米酵菌酸产生能力差异较大,菌株Y2的米酵菌酸产生能力明显高于其他菌株,而且很容易在湿米粉和湿粉条样品中产生米酵菌酸,并且样品中含有大米比只有淀粉产生更高浓度的米酵菌酸。结果表明,湿米粉和湿粉条的原料米中均有唐菖蒲伯克霍尔德氏菌(椰毒假单胞菌酵米面亚种)和米酵菌酸污染的风险,需要加强对其生产过程中原料米的污染控制和风险监管。

The contamination of bongkrek acid and Burkholderia galdioli(Pseudomonas cocovenenans subsp.farinofermentans)in the raw rice for wet rice noodle and vermicelli production was investigated,followed by the study on the bongkrek acid production characteristics of strain in the wet rice noodle and vermicelli environment.A total of 158 samples of raw rice,including rice and broken rice,were collected from manufacturers and small workshops of wet rice noodle and vermicelli in Guangdong Province.Among them,45 samples were found to contain bongkrek acid with the contents ranging from 0.838μg/kg to 8.260μg/kg.A total of five suspected strains with characteristics of Burkholderia galdioli were screened and then confirmed to be Burkholderia galdioli(Pseudomonas cocovenenans subsp.farinofermentans)by bongkrek acid production and molecular biological verification.Different bongkrek acid production capacity was found in the strains,among which strain Y2 possessed much higher bongkrek acid production than the other strains.Moreover,strain Y2 was easy to produce bongkrek acid in the wet rice noodle and vermicelli samples,and the samples containing rice were more suitable to produce higher concentrations of bongkrek acid than starch only.The results indicate that there is a high risk of contamination of both Burkholderia galdioli(Pseudomonas cocovenenans subsp.farinofermentans)and bongkrek acid in the raw rice for wet rice noodle and vermicelli production,and it is necessary to strengthen the pollution control and risk supervision of raw rice in their production process.