TY - JOUR AU - Kato, Kazuko AU - Komagome, Noriko AU - Mineki, Machiko AU - Boonmar, Sumalee AU - Morita, Yukio PY - 2020/06/30 Y2 - 2024/03/29 TI - Prevalence of bacterial contamination in uncooked sticky rice samples from markets in Japan JF - The Thai Journal of Veterinary Medicine JA - TJVM VL - 50 IS - 2 SE - Original Articles DO - UR - https://he01.tci-thaijo.org/index.php/tjvm/article/view/244066 SP - 163-167 AB - <p><span class="fontstyle0">We investigated the prevalence of bacterial contamination in uncooked sticky rice samples obtained from markets<br>in Japan. Between June and August, 2019, a total of 25 sticky rice samples were purchased from shops in the Tokyo<br>area. Twenty-two (88.0%) and 10 (40.0%) of 25 sticky rice samples harbored 3.06±0.54 log spc/g of standard plates<br>counts and 2.17±0.23 log cfu/g of enterobacteriaceae bacteria counts, respectively. Three species of Enterobacteriaceae,<br></span><span class="fontstyle2">Pantoea dispersa</span><span class="fontstyle0">, </span><span class="fontstyle2">P</span><span class="fontstyle0">. </span><span class="fontstyle2">ananati</span><span class="fontstyle0">, and </span><span class="fontstyle2">Kosakonia cowanii</span><span class="fontstyle0">, were identified by MALDI-TOFMS-based test. Three (12.0%) of 25<br>sticky rice samples harbored 2.00 log cfu/g of </span><span class="fontstyle2">Bacillus </span><span class="fontstyle0">species. </span><span class="fontstyle2">Bacillus </span><span class="fontstyle0">spp. was not isolated after heat treatment (98 °C<br>for 20 min.) of sample homogenates. Two isolates were identified </span><span class="fontstyle2">B. cereus </span><span class="fontstyle0">by both API 50 CH and MALDI-TOFMS<br>based test. However, one isolate was </span><span class="fontstyle2">B. mycoides </span><span class="fontstyle0">by API 50 CH, but </span><span class="fontstyle2">B. cereus </span><span class="fontstyle0">by MALDI-TOF MS based test. These 3<br></span><span class="fontstyle2">Bacillus </span><span class="fontstyle0">strains harbored no gene encoding the enzyme responsible for cereulide synthesis and had not produced<br>enterotoxin. Our study suggested that some uncooked sticky rice has </span><span class="fontstyle2">Enterobacteriaceae </span><span class="fontstyle0">bacteria and </span><span class="fontstyle2">Bacillus </span><span class="fontstyle0">spp.<br>contamination, however there is no isolate from heat treatment samples in this study. Isolated </span><span class="fontstyle2">P. dispersa</span><span class="fontstyle0">, </span><span class="fontstyle2">P. ananati</span><span class="fontstyle0">,<br>and </span><span class="fontstyle2">K. cowanii</span><span class="fontstyle0">, are usually in the environment and these organisms have been isolated from patients with opportunistic<br>infections. Preventing cross-contamination, from sticky rice to cooked food may be important during preparation and<br>storage in kitchen.</span> </p> ER -