Evaluation of the Toxicity and Toxicokinetics of Cereulide from an Emetic Bacillus cereus Strain of Milk Origin.

Yifang Cui,Xi Xia,Xiaoye Liu,Shuangyang Ding,Kui Zhu,Yuan Liu

doi:10.3390/toxins8060156

Yifang Cui, Xi Xia + Show 4 more

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https://doi.org/10.3390/toxins8060156

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Journal: Toxins	Publication Date: Jun 6, 2016
Citations: 68	License type: CC BY 4.0

Affiliation: China Agricultural University, Duke University

Abstract

Bacillus cereus is an opportunistic foodborne agent causing food poisoning and many infectious diseases. The heat-stable emetic toxin cereulide is one of the most prevalent toxins produced by pathogenic B. cereus, resulting in symptoms such as emesis and liver failure. In the present work, the toxicity and toxicokinetics of cereulide from an emetic B. cereus isolate (CAU45) of raw milk were evaluated. The production of cereulide was tested by a cytotoxicity test and enzyme immunoassay, and confirmed by the presence of the ces (cereulide synthetase) gene and the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. All results showed that the amount and toxicity of cereulide produced by CAU45 was 7 to 15.3 folds higher than the reference emetic B. cereus DSMZ 4312. Cereulide in plasma was collected at different time points after a single intravenous injection to evaluate its toxicokinetics in rabbits. The maximum concentration of cereulide was achieved in 2.6 ± 3.4 h after administration, with the elimination half-life of 10.8 ± 9.1 h, which expands our understanding of the toxic effects of cereulide. Together, it suggests that urgent sanitary practices are needed to eliminate emetic toxins and emetic B. cereus in raw milk.

Highlights

B. cereus is a spore-forming, ubiquitously opportunistic pathogen, causing various diseases including food poisoning, fulminant bacteremia, pneumonia and endophthalmitis [1].Foodborne B. cereus causes two types of symptoms: diarrhea and emesis [2]
Non-hemolytic enterotoxin (Nhe) and hemolysin BL (Hbl), and a single component of cytotoxin K1 (CytK1) are potentially responsible for diarrhea [3,4], whereas emetic syndrome is induced by a lipophilic cyclic dodecadepsipeptide cereulide, which previously formed in the contaminated foods
The B. cereus CAU45 strain was tested for the presence of four main toxin genes, nhe, hbl, cytK1 and ces

Summary

Introduction

B. cereus is a spore-forming, ubiquitously opportunistic pathogen, causing various diseases including food poisoning, fulminant bacteremia, pneumonia and endophthalmitis [1]. Foodborne B. cereus causes two types of symptoms: diarrhea and emesis [2]. Non-hemolytic enterotoxin (Nhe) and hemolysin BL (Hbl), and a single component of cytotoxin K1 (CytK1) are potentially responsible for diarrhea [3,4], whereas emetic syndrome is induced by a lipophilic cyclic dodecadepsipeptide cereulide, which previously formed in the contaminated foods. B. cereus can be found in most common food matrices such as rice, pasta and dairy products, and it represents more than 68.0% of foodborne outbreaks in all food types [7]. B. cereus was responsible for 13.4% of bacterial foodborne outbreaks, ranking as the second among the most frequent bacterial causes of foodborne disease in Chinese inland provinces [8].

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