PRODUCTION OF MICROBIAL PROTEIN FROM TREE BARK BY PHANEROCHAETE-CHRYSOSPORIUM

Phanerochaete chrysosporium was grown in fermentors on NaOH‐extracted maple, pine, and cedar barks at the optimum substrate concentration of 1% (w/v). The yields (mg protein/liter) on maple, pine, and cedar were 1500, 1200, and 880, respectively, which are probably due to the different lignin contents of the barks. Lignin is not utilized. The productivities at 30°C obtained for pine (4.07 × 10−2 g protein/liter hr) and cedar (2.63 × 10−2 g protein/liter hr) barks were greater than for maple (2.63 × 10−2 g protein/liter hr). The substrate (bark) was the limiting component of the fermentation. Over the 26–38°C temperature range protein productivity increased by a factor of three (1.55 × 10−2 vs. 4.61 × 10−2 g protein/liter hr) for maple bark. Low agitation rates resulted in an overproduction of cellulase and reduced levels of microbial protein. Copyright © 1978 John Wiley & Sons, Inc.