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Torula herbarum (Pers.) Link Ex. Fr. is a dermataceous fungus regularly associated with dry leaves and twigs of Felia microphylla Liebm. In submerged cultures the organism produces weakantimicrobial substances whengrownin Czapek's or in a malt extract medium.The temperature range for the growth of the organism was found to be 24~28°C and no growth occurred at 5°or 37°C. Nitrogen and carbon utilization studies indicated tyrosine and levulose to be the best sources, followed by ammonium tartrate and glucose respectively. Based on these studies a synthetic mediumwas developed for the optimum production of pigments. Fermentation Fermentation was carried out in shake flasks (500 ml) and in 5-liter fermentors (New Brunswick) through a seed inoculum at 24°G for 96~120 hours. The fermented broths were extracted at unacidified pH (4.5~5.0) into ethyl acetate and the extracts washed twice with water and concentrated under reduced pressure. Whenthe concentrate was kept overnight at-5°C, a crystalline material separated which varied in

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Aspergillus flavus produces an adaptive enzyme (or enzymes) that cleaves the heterocyclic ring of 1 mole of quercetin using 1 mole of oxygen to yield 1 mole of carbon monoxide and 1 mole of the depside, 2-(3′,4′-dihydroxybenzoyloxy)-4,6-dihydroxybenzoic acid. The enzyme acts on chromones that possess a substituent such as a methyl or a phenyl group on carbon 2, a free hydroxyl on carbon 3, and a double bond between carbons 2 and 3. These requirements must also be present in a substrate if production of the enzyme is to be induced. The enzyme was purified 40-fold by treatment with Sephadex followed by adsorption on and elution from diethylaminoethyl cellulose and calcium phosphate gel, then by heating, and finally by precipitation with ammonium sulphate. The enzyme is stabilized towards denaturation by heat, by its substrate, or by low concentrations of ammonium sulphate. It is stable for long periods when lyophilized or stored in solutions at −20 °C. The optimum pH for activity lies between pH 5.0 and 7.0 and maximum stability occurs at pH 6.0.