ABSTRACT
Kuwazuimo (Alocasia odora) and shimakuwazuimo (Alocasia cucullata) are evergreen perennial plants that originated in East Asia. Although inedible, they are occasionally eaten by mistake because they resemble satoimo (Colocasia esculenta), and this has caused food poisoning in Japan. It is not easy to determine the cause of a food poisoning outbreak from the shape or chemical composition when the available sample is small. Therefore, we developed a new primer pair for PCR to identify kuwazuimo and shimakuwazuimo in small samples, based on the internal transcribed spacer (ITS) region of ribosomal DNA. Using PCR with the developed primer pair, we detected all samples of kuwazuimo obtained from the market, while excluding 17 other kinds of crops. The samples were identified as shimakuwazuimo by DNA sequencing of the PCR products. The present PCR method showed high specificity and was confirmed to be applicable to the identification of kuwazuimo and shimakuwazuimo from various crops.
Subject(s)
Alocasia/chemistry , Alocasia/genetics , Food Analysis/methods , Food Contamination/analysis , Polymerase Chain Reaction/methods , Alocasia/poisoning , DNA, Ribosomal , Foodborne Diseases/etiology , Foodborne Diseases/prevention & control , Sensitivity and Specificity , Sequence Analysis, DNAABSTRACT
In the present study, we reviewed food poisoning data published by the Ministry of Health, Labour and Welfare of Japan from 1961 to 2010 in Japan to analyze the trends of plant toxin food poisonings (PTFPs). The annual number of incidents of PTFPs has gradually increased since 1995. PTFPs were predominantly caused by Datura spp., Veratrum spp. and Aconitum spp. Although PTFPs frequently occurred in April and May, poisonings caused by some plants occurred in all seasons, e.g. Datura spp. The major location of PTFPs was "at home", and most of the patients had accidentally harvested poisonous plants. During the past decade, the numbers of incidents of PTFPs caused by Veratrum spp., Narcissus spp., Solanum tuberosum and Alocasia odora were especially increased. Consumer advice to prevent PTFPs associated with certain plants that are cultivated in gardens and contain toxic substances is needed, because PTFPs caused by such plants are increasing. In addition, education of elementary school teachers and children about the potential risks of natural toxins in plants, particularly Solanum tuberosum, is desirable.
