Microbial Toxins Testing

In recent years, increasing attention is drawn to the microbial toxins partly because the growing concerns regarding to food pollution and its toxic effects. Food poisoning can be caused by the ingestion of exotoxins (e.g. staphylococcus enterotoxin, bacillus cereus and clostridium botulinum food poisoning) which are performed in the food, or by the ingestion of food containing large quantity of bacterial cells which then release endotoxins in the gastrointestinal tract.

Microbial toxins have been recognized as the primary virulence factor(s) for a variety of pathogenic bacteria. It has been defined as soluble substances that alter the normal metabolism of host cells with deleterious effects on the host. Most of microbial toxins are secreted in food or inside the human intestines after consumption of contaminated food. Common symptoms of illnesses associated with microbial toxins include diarrhea, vomiting, fever, and in some severe cases, shock, hemorrhagic colitis (HC) and even hemolytic uremic syndrome (HUS), which could lead to death. For example, aflatoxins, a family of toxins can be found on certain agriculture (maize/corn, peanuts, cottonseed, and tree nuts), have been proved to be associated with an increased risk of liver cancer. The main fungi that produce aflatoxins are aspergillus flavus and aspergillus parasiticus, which are abundant in warm and humid regions of the world. Aflatoxin-producing fungi can contaminate crops in the field, at harvest, and during storage. People can be exposed to aflatoxins by eating contaminated plant products (such as peanuts) or by consuming meat or dairy products from animals that ate contaminated feed. In the processes of production, processing, transportation, storage and marketing, grains and other food products can be easily contaminated by microbial. Since the symptoms of foodborne illness may develop within a few hours after consumption of contaminated food, the establishment of fast, accurate and easy-to-use tests for on-site/ in-lab detection of these toxins is of great importance.

To minimize the risk of microbial toxin intake, Alfa Chemistry provides microbial toxins testing for food industry using Chemical/Biological/Immunological assays. Although modern assay methods are rapid and convenient means of testing for bacterial toxins, they are not sufficient in providing toxin biological activity information. Thus, bio assays and related tests remain the choice for some bacterial toxins.

Figure1. a) & b) Contaminated peanuts & corns. c) Aflatoxin.

Peptide toxins caused by cholera and listeria.

Enzyme Linked Immuno Sorbent Assay (ELISA), Polymerase Chain Reaction (PCR), and Biosensing Techniques.

• Lipopolysaccharide (LPS) is the main component of the cell wall of gram-negative bacteria.
  Biosensing Technques, Gas Chromatography-Mass Spectrometer (GC-MS), ELISA, Flow Cytometry (FACS), and Chemiluminescent Measurements.

• Mycotoxin is a toxic secondary metabolite produced by mold, which often includes aflatoxin, ochratoxin and single-end spores.
  High Performance Liquid Chromatography (HPLC), ELISA, Immune Affinity Chromatography (IAC), HPLC-Atmospheric Chemical Ionization Mass Spectrometry, and HPLC- Series Mass Spectra.

• Biogenic amine
  Thin Layer Chromatography (TLC), Reversed Phase High-Performance Liquid Chromatography (RP-HPLC), Ion Chromatography (IC), Gas Chromatography (GC), and Capillary Electrophoresis (CE).

HPLC is famous for its high efficiency, rapidity, high sensitivity, good reproducibility, low detection limit, and accurate quantification characterization. ELISA is widely used in the detection of mycotoxins due to its high sensitivity, specificity, and ease of operation. It is suitable for rapid screening of large numbers of samples. At Alfa Chemistry , we have various detection methods for microorganism-derived toxins detection and quantitation services for food industry. We can provide sensitive, accurate, and reliable results to you and your business. Alfa Chemistry is equipped with advanced analytical equipment and knowledgeable professionals for the analysis and identification of microbial toxins.

Please do not hesitate to contract us if you have any problems regarding microbial toxins testing. We will be sincerely at your service.

References

• Chiou J, Leung A H H, Hang W L, et al. Rapid testing methods for food contaminants and toxicants[J]. Journal of Integrative Agriculture, 2015, 14(11):2243-2264.

• Pimbley D W, Patel P D. A review of analytical methods for the detection of bacterial toxins[J]. Journal of Applied Microbiology, 1998, 84(S1):98S-109S.