The present invention relates to the novel isolated 12 30 strain of Pestalotiopsis microspora capable of producing novel antioxidant and antimycotic agents. The present invention also relates to the novel isolated 3,5,7 trisubstituted isobenzofuranone and derivatives thereof, methods of isolating the novel isobenzofuranone from cultures P. microspora 12 30, and to novel uses of the compound as an antioxidant and antimycotic agent. The present invention further relates to a novel 1,5,7 trisubstituted 1,3-dihydroisobenzofuran and derivatives thereof, methods of isolating this novel compound from cultures of Pestalotiopsis microspora 12 30, and to uses thereof.