Optimization of nutritional and physiological conditions for toxigenic strains of Aspergillus flavus

Abstract

See, stats, and : http : / / www . researchgate . net / publication / 260165927 Optimization conditions flavus ARTICLE Impact : 0 . 54 : 10 . 5897 / AJMR12 . 1640 DOWNLOADS 43 VIEWS 240 1 : Melvin VIT 15 SEE Available : Melvin Retrieved : 16 The objective of the present work was to evaluate the capacity of two isolates of Aspergillus flavus from sugar cane (SC) , SC - 3 and SC - 5 to produce aflatoxin under different culture conditions . Aflatoxin B 1 (AFB 1) production was determined in four different media and culture conditions (temperature and pH) were varied to achieve maximal toxin production . AFB 1 was extracted directly from the cultures with chloroform . Thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were used to identify AFB 1 . It was observed that A . flavus cultures SC - 3 and SC - 5 produced highest AFB 1 when grown in potato dextrose medium (PD) and maximum mycelium production in sabauroud dextrose medium (SD) . Supplementation of potato dextrose medium with peptone (PD+P) and sodium nitrate (PD+SN) , AFB 1 production increased by 27 and 20% respectively when compared to the control . The effect of pH and temperature on aflatoxin production by A . flavus was examined in peptone containing PD medium . The results concluded that AFB 1 production and mycelial growth was maximum at pH 5 . 6 when incubated at 27°C in potato dextrose medium supplemented with peptone .