ABSTRACT
Assessment of amino acid decarboxylase activity can be conducted using tubed broth or plated agar. In this study, the test was carried out in microtitre plates containing lysine, ornithine, arginine, tyrosine, tryptophan, phenylalanine or histidine as biogenic amine precursors. Møller decarboxylase base broth (MDB) with or without 1% of a known amino acid were added to wells of a 96 well-microtitre plate. The wells were inoculated with Escherichia coli, Klebsiella pneumoniae, Acinetobacter anitratus or Staphylococcus aureus to the final concentration of 6.0 x 107 cfu/ml and incubated at 35oC. The absorbance of the culture broth was read at 570 nm at 0, 1.0, 2.0, 3.0, 4.0, 5.5, 6.5 and 7.5 hour. Comparison of means of A’570 between 0 hour and a specified incubation time was determined statistically. Positive decarboxylase activities were detected in the media inoculated with E. coli and K. pneumoniae in less than 6 hours. The current method is suitable for immediate producers of amino acid decarboxylase enzymes. It costs less as it uses less amino acid and it has the potential to be used for screening aliquots of food materials for amino acid decarboxylase activities.
ABSTRACT
The high level of glucose in blood for a long duration is the main cause of the development of retinopathy. So yearly screening of patients newly diagnosed with NIDDM diabetes is recommended because rare cases of treatable diabetic retinopathy have occurred early in one course of NIDDM diabetes. Hyperglycaemia leads to non-enzymatic glycosylation of proteins and HbA1C was found increased. Antioxidants such as GSH and SOD level is found decreased in retinopathy conditions due to the higher lipid peroxidation, which is evident from high MDA and DC values. So it can be clearly stated that increase in the free radical by hyperglycaemia, lipid peroxidation and advanced glycosylation endproducts along with decreased antioxidants are the causative agents for the development of retinopathy.