Penicillium sp I which produces a powerful hydrolysing enzyme was isolated from putrefid and dry Jerusalem artichoke medium. The strain was used to study on the optimum culture conditions for enzyme production. The results obtained are as follows:
1. Penicillium sp I was a vigorous strain to produce inulase.
2. The optimum culture conditions of the strain was examined in the Jerusalem artichoke extract medium and the synthetic medium.
3. Inulase productivity in the Jerusalem artichoke extract medium was higher than that of the synthetic medium.
4. The optimum culture period of the Jerusalem artichoke extract medium was four days, whereas that of the synthetic medium was five days.
5. The optimum temperature, pH and concentration in the Jerusalem artichoke extract medium were 30℃, 5.0 and 4.0% (W/V), respectively.
Meanwhile, the optimum temperature, pH and concentration in the synthetic medium were 30∼33℃, 5.0∼6.0, and 1.0∼1.5% (W/V), respectively.
6. Corn steep liquor, peptone, (NH₄)₂HPO₄, NH₄H₂PO₄, (NH₄)₂SO₄, etc. were favorable as nitrogen sources. Of these, especially, Corn steep liquor and peptone as organic nitrogen sources caused an increase in inulase production in the synthetic medium.
7. All sugars except for inulin have no effect upon the inulase production.
8. KCl, MgSO₄ and FeSO₄ were favourable mineral sources for inulase production.
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