Influence of aeration and agitation rate on the xylanase activity from Penicillium janthinellum

Penicillium janthinellum was cultivated in sugar cane bagasse hemicellulosic hydrolysate. The maximum xylanase activity obtained in shake flasks was 98 U ml(-1) at 60 min(-1) agitation rate, 30 degrees C and pH 5.5. The growth of the P.janthinellum in a 4 litre fermentor was studied to determine the influence of aeration and agitation rate on xylanase production. Three agitation rates (100, 300 and 400 min(-1)) and three aeration rates (0.2, 0.4 and 0.6 vvm) were used. Xylanase synthesis was growth associated and a function of K-L a. The highest enzymic activity (8.9 U ml(-1)) was obtained at a very low oxygen supply, at a K-L of a 1.24 h(-1).