Process for the microbiological oxidation of steroids

In a process for the production of 17-hydroxyandrosta-1,4-dien-3-one and/or androsta-1,4-diene-3,17-dione by fermenting a sterol, its 4-en-3-one sterol derivative or its 1,4-dien-3-one sterol derivative in a culture medium containing a chelating agent capable of forming a chelate compound with iron and copper ions with a microorganism capable of microbiologically oxidizing said sterol or its derivatives to produce 17-hydroxyandrosta-1, 4-dien-3-one and/or androsta-1,4-diene-3,17-dione, the improvement which comprises adding to the culture medium at least one glyceride-containing substance selected from the group consisting of glycerides, fats, oil seeds and oil fruits in an amount sufficient that the culture medium contains at least 0.3 percent by weight of glycerides and adding at least 0.1 wt.% of vegetable oil meal.

In a process for the production of 17-hydroxyandrosta-1,4-dien-3-one and/or androsta-1,4-diene-3,17dione by fermenting a sterol selected from the group consisting of cholesterol, stigmasterol, campesterol and sitosterol;

• its 4-en-3-one derivative or its 1,4-dien-3-one derivative in a culture medium containing a chelating agent capable of forming a chelate compound with iron and copper ions with a microorganism selected from the group consisting of Arthrobacter simplex, and Brevibacterium lipolyticum, the improvement which comprises adding to the culture medium at least one glyceride-containing substance selected from the group consisting of glycerides, fats, oil seeds and oil fruits in an amount sufficient that the culture medium contains from 0.7 to 3.0 percent by weight of glycerides, and an amount of a vegetable oil meal which is from 0.6 to 20 times the weight of the glyceride-containing substance to give the concentration of the vegetable oil meal in the culture medium in the range of from 1 to 8 percent by weight.