Novel antimicrobial activities of Ganoderma lucidum and Laetiporus sulphureus for agriculture

Mushrooms have many unique properties that play important roles in society. They are sustained in organic matter and especially on dead and rarely in living material. In this process, they produce many kinds of degradative enzymes. Because of their degradative activity, they are crucial in the carbon cycle and for bioremediation of organopollutants in the environment. Several species of mushrooms are edible including shitakii, oyster, and button mushrooms. Many mushrooms have recognized applications in medicine and pharmacology. The antimicrobial activity of some basidiomycete mushrooms provides efficient and low cost for human and plant disease control. Thus, we have chosen to evaluate the antimicrobial activity of two basidiomycetes, Ganoderma lucidum and Laetiporus sulphureus, against plant pathogens. Liquid compost factor (LCF), a product derived from pineapple waste material inoculated with cultures of L. sulphureus, was also included in our evaluations.; Bioactive culture fluids by G. lucidum and L. sulphureus were produced in stationary conditions using 2000 ml Erlenmeyer flasks containing 200 ml of media at pH 3.0, and incubated at 30°C. Culture fluids produced in different media were evaluated for their antibacterial, antifungal, and antinematode activity. In all experiments, non-inoculated media were used as controls.; Bactericidal activity was observed in culture fluids of G. lucidum and L. sulphureus. Both fungi produced strong bactericidal activity against Agrobacterium rhizogenes, A. tumefaciens, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv. syringae, and Xanthomonas campestris pv. campestris. No activity was observed against Burkholderia cepacia, Pseudomonas corrugata, Pseudomonas fuorescens, and Xanthomonas campestris pv. translucens while Brennaria quercina, and Rathayibacter tritici were slightly inhibited. Culture fluids that were freshly harvested (21-day old) or stored for 90 days at room temperature had the same amount of activity. Similar results to fresh culture fluids were observed when culture fluids were boiled for an hour. However, slight growth inhibition was not observed with B. quercina and R. tritici.; The mycelial growth of test fungi were reduced from 0 to 71 percent depending on fungal species tested. This antibiotic activity and appeared to be stable over 90 days of storage at room temperature. Rich broth medium (RBM) alone did not inhibit the test fungi. Phoma medicaginis was most inhibited while no inhibition was observed with Rhizopus sp. (Abstract shortened by UMI.)...