Similarties in Toxicity of Pathogenic Fungus (phoma Medicaginis) and Chromium (vi)

Phoma medicaginis is a deuteromycete fungus that grows on a variety of plants, a few of which are used in herbal medicines. The current work attempts to establish the possible mechanism of toxicity of this fungus, in case it is consumed by animals as fungus infested food. Chromium (VI) is a known pollutant, the toxicity of which is manifested through the oxidative stress exerted on the animals that happen to consume food contaminated with it. Chromium (VI) is capable of generating the reactive oxygen species (ROS), which in turn, may react with the biomolecules in the tissues leading to degenerative changes; TBARS (thiobarbituric acid reactive substance) and protein carbonyl are routinely used indices of oxidative stress. When Swiss albino rats were fed on food contaminated with chromium (VI) and biomass of Phoma medicaginis it was observed that the TBARS content, which in turn is proportionate to lipid peroxidation of liver, kidney and brain tissues was found to rise above that of control rats. The protein carbonyl content that serves as a measure of degradative changes in proteins by reactive oxygen species was also found to be high in these tissues of rats fed on diet contaminated with chromium (VI) as well as fungal biomass. The weight loss observed in the treated rats could well be ascribed to the decrease in protein as well as carbohydrate contents of the tissues analyzed. A corresponding increase in free amino acid and reducing sugar contents of the respective tissues of treated rats were noticed. Ascorbic acid and α – tocopherol are employed in managing the oxidants and so is the cholesterol that may be utilized for synthesizing regulatory hormones to achieve the same result. The fact that ascorbic acid and α – tocopherol content were low and the total cholesterol content was high in all tissues of rats receiving diet contaminated with chromium (VI) and fungal biomass confirmed that the toxicity of the fungus is manifested through the generation of oxidative stress identical to the one by chromium (VI).