Botulogenic Properties of Vegetables With Special Reference to the Molecular Size of the Toxin in Them

The molecular sizes of Clostridium botulinum type A, B, E, and F toxins produced in string beans, mushrooms, tuna fish and pork were determined to provide an explanation for the high botulogenic properties of vegetables. Type A and B organisms produced the orally more toxic 16S and 19S molecular‐sized toxins in vegetables, whereas they produced the orally less toxic 12S and only rarely some 16S toxin in tuna fish and pork. Type E and F organisms produced only 12S toxin in any food or culture medium, but addition of glucose seemed essential for appreciable toxin production. It appeared that the molecular sizes of type A and B toxins transform depending upon the content of iron and manganese salts in foods.