Effect of Magnetic Field Energy on the Growth and Aflatoxin Production by Aspergillus flavus

number: 
2908
إنجليزية
Degree: 
Imprint: 
Biotechnology
Author: 
Aieman Muhammad Ahmad
Supervisor: 
Dr. Abdul-Ghani I. Yahya
Dr. Abdul-Wahid Sh. Jabir
year: 
2010
Abstract:

The study was conducted to conclude the effect of the magnetic field poles on aflatoxins produced by toxogenic Aspergillus flavus. The fungus had been exposed to the northern pole, southern pole; both poles and their influences were compared with the control at which the fungus is not affected by magnetic field energy. A. flavus was subjected to magnetic field energy which applied through a magnet at different forces (5, 7,10,30,50 Gauss) for seven days at temperature of 27oC and for three replications. The use of magnetic fields poles as new detoxification method that did not cause heating of tissues or damage to the nutritive value of the crops, but only inhibit organisms living cells or their secondary metabolites. Magneto-biological effects have unique features that obviously distinguish them from thermal effects. Also, they are dependent on simultaneously static magnetic fields and their poles. The quality of this effect is the same but the quantity of the effect is dependent on the chemical structure of metabolites. The effect of magnetic field poles was observed on the growth of Aspergillus flavus on solid media. The southern pole had a positive effect on the growth of A. flavus by increasing the diameter of the colony (7.3-8 centimeters) developing on solid media, while the northern pole had a negative influence on the growth of A. flavus, with (3.5-4 centimeters) diameter of the colony, while the treatment of northern and southern poles together and the control treatment is (5-6 centimeters) respectively. A similar result was obtained, when the effect of magnetic field poles was detected on the growth of A. flavus in liquid media, which increased by the influence of southern pole, because of the turbidity and so the absorbance of the spectrophotometer was also increased and the percentage of the growth was (173.2 %). While it decreased through the effect of northern pole (65.5 %), on the other hand the control (which had no effects) and both poles are the same in the percentage of the growth (98-100 %). The investigation on the effect of magnetic field poles on the biomass that had reached a dry weight of biomass for the treatment of the southern (4.3 g) and (0.23 g) for the northern, (0.81g and 0.83 g) for each treatment of the poles together and the control treatment, respectively. The most important conclusion that had been observed was the effect of magnetic field poles on the concentration of total aflatoxin produced by A. flavus, which was 454.73 ppb (when treated with southern pole) and 25.40 ppb (when treated with northern pole) while the control 212.46 ppb and both poles 88.33 ppb by using ELISA technique. m The southern pole of magnetic field which had the positive charge while induced the calcium signal transduction and such signaling induced and accelerate the growth of A. flavus , in contrasts when influenced by northern pole (which had the negative charge) it inhibited the calcium signal transduction and so causing inhibition of the growth. Magnetic field may be able to remove bound calcium ions from cell membranes. There was also no doubt that bound calcium ions were essential for the stability of these membranes. Consequently, their loss would increase temporary pore formation under the mechanical stresses from pressure differences within the cell and abrasion by its moving ontents. This very simple conclusion can account for virtually all of the known biological effects of electromagnetic fields, including changes in metabolism and genetic damage. Also the influence of magnetic field poles on the activity of some A. flavus enzymes such as amylase and protease were affected because the southern pole which had a positive effect on the enzymes activity, while for the northern pole had a negative influence enzymes activity however the treatment of northern and southern poles together and the control had the same value. The impact of the magnetic field on the enzymes were concentrated on changing the charge and thus the shape of the active site of enzymes and not on the substrate, because when we develop and encourage the organism to produce the enzymes under the effect of magnetic field there would be a marked change in the enzymatic activity and difference between the two, north and south poles. The influence of magnetic field poles on the protein concentration in A. flavus was affected hence the southern pole which had a positive effect on the protein concentration, while the northern pole had a negative influence on protein concentration .however, the treatment of northern and southern poles together and the control has the same amount. The effect of magnetic field poles was studied on the reducing sugars concentration which decreased in the treatment of the southern (0.23 mg/ml) and increased up to (0.32 mg/ml) in the northern, while (0.28 mg/ml and 0.29 mg/ml) for each treatment of the poles together and the control treatment, respectively. the northern pole, which reduced the growth of A. flavus in the culture of solid and /or liquid media , it will increase the concentration of reducing sugars due to lack in the effect of magnetic field on the substrate which are carbohydrates, while for the southern pole, which accelerate growth and lead to decrease the reducing sugars in the organism .