Manganese-enhanced biotransformation of atrazine by the white rot fungus Pleurotus pulmonarius and its correlation with oxidation activity

Manganese enhanced atrazine transformation by the fungus Pleurotus pulmonarius when added to a liquid culture medium at concentrations of up to 300 microM. Both N-dealkylated and propylhydroxylated metabolites accumulated in the culture medium, with the former accumulating to a greater extent than did the latter. Lipid peroxidation, oxygenase and peroxidase activities, and the cytochrome P-450 concentration increased. In addition, an increase in the spectral interactions between atrazine and components in the cell extract was observed. Antioxidants, mainly nordihydroguaiaretic acid, which inhibits lipoxygenase, peroxidase, and P-450 activities, and piperonyl butoxide, which inhibits P-450 activity, inhibited atrazine transformation by the mycelium. It is suggested that the stimulation of oxidative activity by Mn might be responsible for increasing the biotransformation of atrazine and for nonspecific transformations of other xenobiotic compounds.</jats:p

Introduced Tuber aestivum spreading spontaneously in Israel

A T. melanosporum plantation was established during 1994-95 in Kibbutz Bar´am in the Upper Galilee, Israel. In 1998, only approximately 70% of the trees maintained the inoculated mycorrhiza. A number of trees died; thus, several tree species were initially introduced. These included both European and local oak species, as well as hazelnuts. In 1999, seedlings were introduced into the plantation to fill the gaps between trees. These included, inadvertently, plants inoculated with T. aestivum. In July 2009, fruiting bodies of T. aestivum were collected from the plantation. In 2010, a manual search was conducted and a total of 2.2 kg of fruiting bodies of T. aestivum (a calculated yield of approximately 6.0 kg/acre) were obtained. No fruiting bodies were collected in 2011. In 2012, truffles were found in the original plantation and in a grove within a research farm approximately 3.5 km away. The latter appeared to be of the same origin as the originally introduced T. aestivum. The environmental conditions in the Upper Galilee, although unsuitable for T. melanosporum, are highly suitable for the more robust T. aestivum, which thrives on local oak species