Effect of different concentrations of sodium chloride on the growth and the biochemical activities of aspergillus flavus link

ABSTRACT

The effect of different sodium chloride concentrations on the growth and aflatoxin B 1 production, as well as protein, total nitrogen, nucleic acids, free amino acids and elemental composition of Aspergillus flavus link isolate was studied. The following is a brief summary of the results: Aflatoxin B 1, protein and nucleic acids production decreased with increasing sodium chloride medium concentration. The free amino acids proline, valine, phenylalanine and arginine showed a notable increase at the concentration of 5% compared with control values, while the amounts of all detectable amino acids at 25% showed very marked increases compared with the values of control or 5%. Methionine, histidine and lycine appeared only at 25%. Sodium chloride induced proline synthesis, its amount increased as sodium chloride increased until it reached maximum at 20%. The amount of total nitrogen showed remarkable decrease at 5%, it reached 19. 05% less than its respective control value, while its value very markedly increased at 25% and reached 43. 68% more than its control value. Also, the amount of total amino acids decreased at 5%, it reached 10. 75% less than its control value, while its value showed remarkable increase at 25% and reached 1270.05% more than its control value. Sodium ion concentration increased at all sodium chloride concentrations, while potassium, iron and magnesium concentration decreased at all sodium chloride concentrations