A potent lytic strain was selected by an extensive screening test of microorganisms isolated from soils and sewages on the medium containing baker´s yeast as a carbon source. This strain (M-10) was identified to a strain of Humicola sp. by the Genera of Fungi (Clements, 1964).
The strain was cultured on the basal medium composed of 2% of baker´s yeast, 0.3% of K₂HPO₄, 0.01% of MgSO₄·7H₂O, 0.1% of yeast extract in a shaking incubator. Cultural conditions for lytic enzyme production has been studied, and the results obtained were as follows:
1. The Optimal conditions for lytic enzyme production were: initial pH 5.5 to 6.0, temperature 33℃ in shaking culture.
2. Among the various carbon sources, baker´s yeast (4%) was the best for lytic enzyme production, increasing the level of activity eight, times higher than when grown on glucose (1%).
3. The most effective concentration of K₂HPO₄ and MgSO₄·7H₂O in the basal medium for lytic enzyme production was 0.1% and 0.01% respectively.
4. When the strain was cultured under the optimal conditions, the production of lytic enzvme was maximized in 72 hours.
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