Production of Ligninases and Degradation of Lignin in Agitated Submerged Cultures of Phanerochaete chrysosporium

Abstract

Research on the extracellular hemeprotein ligninases of Phanerochaete chrysosporium has been hampered by the necessity to produce them in stationary culture. This investigation examined the effects of detergents on development of ligninase activity in agitated submerged cultures. Results show that addition of Tween 80, Tween 20, or 3-[(3-colamidopropyl)dimethylammonio]l-propanesulfonate to the cultures permits development of ligninase activity comparable to that routinely obtained in stationary cultures. The detergent-amended cultures express the entire ligninolytic system, assayed as the complete oxidation of [14C]lignin to '4CO2. The detergent effect is evidently not merely in facilitating release of extant enzyme. Development of ligninolytic activity in the agitated cultures, as in stationary cultures, is idiophasic. Ion-exchange fast protein-liquid chromatography indicated that the heme protein profiles in agitated and stationary cultures are very similar. These findings should make it possible to scale up production of ligninolytic enzymes in stirred tank fermentors.

Characterisation of deactivating agents and their influence on the stability of manganese‐dependent peroxidase from Phanerochaete chrysosporium

“…Spores were collected by adding a small quantity (1–8 cm 3 ) of 0.9% (w/w) NaCl to the slants or plates. The spore solution was filtered through glass‐wool, and kept at −20 °C until used 23…”

Stimulation of ligninolytic enzyme production in Phanerochaete chrysosporium by polyoxyalkanes

“…Enzyme production by P. chrysosporium in agitated culture is usually low (about 20 U l −1 ). Jäger et al . (1985) observed that addition of the surfactant Tween to the shaken culture greatly enhanced LiP production.…”

“…It has been shown that the effect is not only because of the release of formed enzymes (Jäger et al 1985) but also to their enhanced production (Perdih and Les˘tan 1993) following the enhanced oxygen supply to the cells (Les˘tan et al 1994). The question of what is the molecular basis of this effect remains open and which substances are the best stimulators of LiP production is also unknown.…”

Continuous production of manganese peroxidase byPhanerochaete chrysosporium immobilized on polyurethane foam in a pulsed packed-bed bioreactor

“…Surface area was determined with a Micromeritics ASAP 2000 with degasified foam cubes at room temperature and at a pressure of 10 −3 mm Hg. Erlenmeyer flasks (250 mL) containing 90 mL of an N-limited medium described by Tien and Kirk (1988) with 10 g L −1 glucose in a 20 mM sodium acetate buffer (pH 4.5) and 1.8 g of polyurethane foam were inoculated with 10% (v/v) homogenized mycelium produced from germinated spores (Jager et al, 1985). The cultures were incubated in an orbital shaker (New Brunswick Scientific, Innova 4000) at 37°C and 150 rpm.…”

“…The objective of this article is to establish the conditions allowing continuous production of MnP for extended periods of time. A pulsed flow bioreactor packed with immobilized P. chrysosporium was selected for two reasons: immobilization of fungi on polyurethane foam could be effective to enhance MnP production because it might significantly increase mycelium-fluid contact, thus improving mass and oxygen transfer rates (Jager et al, 1985); and pulsation has been proved to improve mass transfer rate in fixed-bed bioreactors . Factors such as nutrient feed rates, operating hydraulic retention time (HRT), Mn +2 concentration, the use of oxygen versus air, and recycling flow were considered for optimization of MnP production.…”