Abstract
In the current study, the possible role of environmental conditions (incubation period, incubation temperature, pH value) and nutritional requirements (carbon source, nitrogen sorce) for maximum production of citrinin by Penicillium viridicatum Westling were investigated. The optimum conditions for citrinin production were incubation for 8 days at 30 degrees C on buffered broth medium (pH 5.0) contain sucrose and yeast extract as carbon and nitrogen sources, respectively. Propolis caused significant decrease in both growth and citrinin production of P. viridicatum. The alteration in mycelial amino acids content of P. viridicatum due to propolis indicated cellular damage by enhancing the instability and harmful hydrolysis of proteins towards catabolism.