Growth and oxidative enzymatic activity of in-vitro cultures of Ciliochorella buxifolia

Abstract

To get a better insight into the physiological capabilities of Ciliochorella buxifolia, the most frequent fungus occurring on Scutia buxifolia leaf-litter in a native forest from Argentina, its in-vitro ability to use 10 carbon sources and to produce extracellular enzymes, including its response to tannic acid and to the addition of a water-soluble fraction of Scutia buxifolia leaf-litter, was analyzed. Growth, colony morphology and extracellular enzyme activity as well as differentiation of pycnidia were a function of the C substrate. The fungus responded to the presence of tannic acid in a range between 0.001 and 0.1% (w/v), by increasing growth, but higher phenol concentrations like 0.5% were inhibitory. The activity of extracellular oxidative enzymes increased with the concentration of tannic acid. Furthermore, the fungus showed extracellular laccase and peroxidase activity, being the former increased by water-soluble fraction in association to pycnidia development. Based on these results, Ciliochorella buxifolia is a fungus growing on Scutia buxifolia leaf-litter that is able to metabolize soluble phenolic compounds, which triggers the synthesis of extracellular oxidative enzymes possibly involved in sporulation and detoxification reactions.