Effects of temperature, pH and curing on the viability of <i>Sarcocystis,</i> a Japanese sika deer (<i>Cervus Nippon centralis</i>) parasite, and the inactivation of their diarrheal toxin

Abstract

Recently, the Sarcocystis parasite in horse and deer meat has been reported to be a causative agent of acute food poisoning, inducing nausea, vomiting and diarrhea. Compared with other causative agents, such as bacteria, viruses and other parasites, in deer meat, the Sarcocystis species parasite, including its stability under various conditions, is poorly understood. In this study, we assessed the viability of Sarcocystis spp. and the activity of their diarrhea toxin (a 15-kDa protein) in deer meat under conditions of freezing, cold storage, pH change and curing. In addition, the heat tolerance was assayed using purified bradyzoites. The results showed that the species lost viability by freezing at −20, −30 and −80°C for <1 hr, heating at 70°C for 1 min, alkaline treatment (pH 10.0) for 4 days and addition of salt at 2.0% for <1 day. Immunoblot assays showed that the diarrhea toxin disappeared together with the loss of viability. However, the parasite survived cooling at 0 and 4°C and acidification (pH 3.0 and 5.0) for more than 7 days with the diarrhea toxin intact. These results provide useful information for developing practical applications for the prevention of food poisoning induced by diarrheal toxin of Sarcocystis spp. in deer meat during cooking and preservation.

First Case Report of Possible <i>Sarcocystis truncata</i>-induced Food Poisoning in Venison

“…To date, S. sybillensis , S. wapiti , and S. hofmanni have been identified in Japanese sika deer ( C. nippon ) (4, 14). S. truncata has been identified in white-tailed sea eagle (15) and red deer ( C. elaphus ) in Norway (16) but never in sika deer ( C. nippon ) in Japan.…”

Detection of <i>Sarcocystis</i> spp. and Shiga toxin-producing <i>Escherichia coli</i> in Japanese sika deer meat using a loop-mediated isothermal amplification-lateral flow strip

“…Due to the high contamination frequency in meat or feces in Japan, Sarcocystis spp. and STEC [9, 13] were chosen as the subjects in this study.…”

“…According to a previous paper, some species of Sarcocystis have been parasitic to Japanese sika deer [9], such as S. wapiti , S. sybillensis , and S. hofmanni . However, except for S. wapiti , the DNA sequences of these species have never deposited in databases, so the sequences of the predominant Sarcocystis species in deer meat obtained from Yamanashi Prefecture, Japan, were determined in order to construct LAMP primers for SarcoR .…”

“…The bradizoids were prepared from Sarcocystis spp. according to the previous paper [9]. The Sarcocystis spp.…”

“…We previously reported the presence of at least four species of Sarcocystis spp. in Japanese sika deer meat samples obtained from Yamanashi Prefecture, Japan [9], and designed our primers based on information in the 18S rRNA region of the predominant Sarcocystis spp ., among the 21 reported species. The results of cross-reaction experiment suggested that DNA strip for Sarcocystis spp.…”