Ten different strains of the genera Escherichia, Streptococcus, Staphylococcus, Yersinia, Salmonella, Erysipelothrix and Lactobacillus were used as test micro-organism s. The inhibitory effect in vitro was defined as the difference between the growth rate without mycotoxins and the growth rate in the presence of a mycotoxin. AFB 1 affected the growth of Yersinia enterocolitica. The growth rate of Escherichia coli and Salmonella infantis was decreased by FB 1 . Thus, using appropriate tester strains it should be possible to set up a broad-range mic rotubidimetry assay for individual mycotoxin screening in vitro.
Some mycotoxins directly inhibit the growth of micro-organisms.
Others affect the nervous system, induce Ever and kidney damage, or even cause vomiting in some species. Clinical syndromes in farm animals range from acute death to chronic disease and from reproductive deficiencies to overall debilitation. The development of sensitive, rapid, and reproducible in vitro assays is an absolute require ment for the screening of known and unknown mycotoxins. Assays with micro-organisms are usually less expensive and time consuming than those using cell culture or animals, and have already been used to evaluate the cytotoxic and mutagenic effects of mycotoxins. Hitherto, only limited information has been published on the antimicrobial potential of mycotoxins using novel microtitration tray-based turbidimetric techniques.