Effect of Static Magnetic Field on Aflatoxin Production by Aspergillus flavus under Solid State Fermentation

    The fungus Aspergillus flavus was exposed to the north pole of the magnetic field and then compared its effect with the control treatment (without the magnetic field energy). The substrates used for the growth of A. flavus  (corn, wheat, rice and wheat flour) were obtained from the local market and sterilized by autoclaving. A  static magnetic field of 100 gauss was subjected to the A. flavus for (7, 14
and 21) days under solid state fermentation at 28 °C and 25% moisture content. The concentration of aflatoxin B1 has been determined by Enzyme Linked Immunosorbent Assay (ELISA). At the end of each fermentation period and according to the extraction procedure provided with the ELISA kit, the  substrates were grounded (corn, wheat and rice) and mixed  with  a specific amount of methanol then filtered through Whatman filter paper No 1. The extract was  tested for  the  aflatoxin B1 concentration  and  the  results  were  statistically  analyzed.The results showed that the  north pole significantly decreased the aflatoxin B1 concentration for the corn during (7, 14 and 21) days, which were (0.540, 0.489 and 0.388) ppb respectively. The northern pole also significantly decreased the aflatoxin B1 concentration for the wheat for the two periods (7and 14) days, whichwere (0.274and 0.356) ppb, respectively, but  there were no significant differences in the last period (21days) as compared with previous periods as well as and therewas no significant differences at this period(21days)  between the control and north pole treatment. While for the rice, the northern pole significantly decreased theaflatoxin B1 concentration for the three periods (7, 14 and 21) days, which were(0.166, 0.033 and 0.026) ppb respectively, but  there are no significant differences in the last period (21days) between the control and the north pole treatment, while there was no effect of the north pole for the wheat flour with some rise in the proportion of aflatoxin B1 (0 0.01, 0.08 and 0.2) ppb, respectively as compared with control treatment, and this would be due to the low moisture content in the three periods (7,14, 21) days. This study clearly  demonstrated that there are significant effects of the static magnetic field in decreasing the aflatoxin B1 concentration produced by  A. flavus in agro-product (wheat, rice and wheat flour and corn).