Inhibition of heterocyclic aromatic amine formation in fried ground beef patties by organosulfur compounds in garlic

The effect of organosulfur compounds on heterocyclic aromatic amine (HAA) formation and overall mutagenicity in fried beef patties was studied. Organosulfur compounds (0.67 mmol) were added directly to 100g of ground beef and fried at 225°C for 10 min per side. HAAS were isolated by solid phase extraction and quantitated by high performance liquid chromatography (HPLC). Concentrations of 2-amino-lmethyl-6-phenylimidazo[4,5-b] pyridine (PhIP), the major HAA in muscle foods, were reduced by 81 and 69% by diallyl disulfide (DAD) and dipropyl disulfide (DPD), respectively, while cysteine and cystine were less effective inhibitors.; In a second series of experiments, the effect of organosulfr compounds on HAA formation in fried ground beef patties and mutagenicity was evaluated by HPLC analysis and the Ames Salmonella typhimurium assay. The greatest inhibition of HAA formation was observed by DAD and DPD, with reductions of 78 and 70%, respectively. The overall mutagenicity of the fried beef patties was reduced 75 and 65% by DAD and DPD, respectively. The measured mutagenicity in fried beef patties was quite similar to the mutagenicity values calculated from the determined concentrations of HAAs.; A series of model system studies were conducted to more completely understand the mechanism by which HAA formation is inhibited by sulfur compounds. The concentrations of PhIP increased 3-4 fold when glucose was added to the model system containing phenylalanine and creatinine. These studies confirmed glucose as an important contributor to HAA formation. Organosulfur compounds and sodium bisulfite effectively inhibited HAA formation in model systems containing phenylalanine, glucose, and creatinine. However, these compounds had no effect on HAA formation in the model systems that did not contain glucose. A possible mechanism of HAA inhibition by DAD and DPD in model systems containing glucose could be through their interaction with glucose. A number of sulfur-containing compounds such as tetrahydrothiophene-3-one (THT) and tetrahydrothiophene (THP) were produced by heating glucose and DAD at 180°C for 30min. However, THT and THP had no effect on HAA formation in the various model systems, regardless of whether glucose was present or not. THT and THP are merely reaction products between glucose and DAD and do not influence HAA formation.; While these experiments point to a competitive reaction between organosulfur compounds and amino acids for glucose, the mechanism by which these compounds inhibit HAA formation is still not fully clarified. However, the observation that DAD has no effect on HAA formation in model systems without glucose provides supporting evidence that the interaction of DAD with glucose is a possible key element in its inhibition of HAA formation. It is also apparent that the products of interaction of glucose and DAD are not directly involved in the inhibition process.