Conidia were harvested from 30-d-old stock cultures, by adding 5 mL of sterile distilled water to the agar slant and then resuspending the conidia.

The spore concentration in the conidial suspension was determined by counting with a Burker Counting Chamber. To prepare the inoculum, 1 mL of spore suspension (approx 4 x 107 spores/mL) was inoculated into a 300­mL Erlenmeyer flask containing 75 mL of growth medium similar to the basic nutrient medium of Mandels and Weber (13) with the exception that urea was omitted, a double amount of (NH4)2SO4 was included, and the peptone content was elevated by 20%. This medium (later referred to as medium with a single set of nutrients) contained 10 g/L of glucose as the sole carbon source, which was fed separately in the form of a thick solution to the salt medium after sterilization. The initial pH of the sterilized medium was adjusted to 5.0 by adding sterile 2 M H2SO4 before inoculation, and no pH control was applied during the cultivation run. The inoculum was incubated on a rotary shaker with an agitation rate of 200 rpm at 30°C for 3 d and then was used to inoculate the fermentor.