ASSESMENT OF AFLATOXINS IN ANIMAL FEED AND THEIR CONTROL STRATEGIES

Aflatoxins are mycotoxins mostly produced by Aspergillus flavus and Aspergillus parasitiucus. Aflatoxins contaminate the food and feed during storage, growth and harvest. It is known that ingestion of aflatoxins can lead to very serious health problems such as liver damage and carcinogenesis. Different physical, chemical and biochemical procedures have been used so far for controlling aflatoxins in the feed samples. This present research work has been designed to evaluate the antifungal activities of various medicinal plant leaves (Psidium guajava, Ficus benghalensis, Citrus paradisi, Gardenia radicans, Ficus religiosa, Vitis vinifera, Punica granatum, Morus alba and Ziziphus Jujuba) and chemicals (citric acid, ascorbic acid, acetic acid, sodium bicarbonate, lactic acid, oxalic acid and sodium chloride) against A. flavus and A. parasitiucus, to minimize the mould growth and aflatoxin production in poultry feeds during storage. The antifungal and antioxidant components of medicinal plant leaves were extracted by using aqueous methanol and Vitis vinifera presented maximum extract yield (22.1 g/100g DW). Antioxidant analysis of medicinal plant extracts performed in terms of total phenolic and total flavonoid contents, showed that Punica granatum offered highest total phenolic contents (47.6 mg GAE/g DW), whereas Morus alba gave maximum total flavonoid contents (114.9 mg CE/g DW). Crude extracts were further analyzed for bioactive constituents (phenolic acids) by HPLC. Total of 9 phenolic acids were investigated on the basis of availability of standard chemicals. The concentration of phenolic acids was found to be significantly different (p< 0.05) among tested medicinal plants. Antioxidant activity was determined by DPPH radical scavenging activity and measure of reducing power. Results revealed that Punica granatum extract showed highest radical scavenging activity and Morus alba extract exhibited maximum reducing potential. Antifungal activity of medicinal plants and chemicals was investigated by Disc Diffusion Method and Minimum Inhibitory Concentration (MIC). Results showed that methanolic extract of Morus alba exhibited highest antifungal potential against both tested fungal strains with maximum zone of inhibition 30 mm for A. paraciticus and 23 mm for A. flavus. Among chemicals sodium bicarbonate showed highest antifungal activity against both tested fungal strains with maximum zone of inhibition 26 mm for A. paraciticus and 22 mm for A. flavus. The poultry feeds (broiler and layer) inoculated with A. flavus and A. parasitiucus were stabilized with different medicinal plants and chemicals and stored at specific moisture (16%) and temperature (28?C) conditions for 6 months. After regular intervals, samples were drawn and levels of aflatoxins were estimated by HPLC. The nutritive quality of the poultry feed was also determined by estimating the proximate composition (ash, protein, fat and fiber contents) and mineral profile (Fe, Ca, P and K contents). Among the investigated medicinal plants and chemicals, Punica granatum, Morus alba and sodium bicarbonate were found to be more effective as they fully inhibited (100%) aflatoxin production throughout the entire storage period. The data was analysed by using LSD to determine the significance of treatment to inhibit aflatoxin production. Overall results of the present study showed that Punica granatum, Morus alba and sodium bicarbonate can be used effectively to make agents to control aflatoxin production in poultry feeds