Effect of culture conditions on the production of ligninolytic enzymes by white rot fungi Phanerochaete chrysosporium (ATCC 20696) and separation of its lignin peroxidase

Abstract

The present work was carried out to determine the optimum culture conditions of Phanerochaete chrysosporium (ATCC 20696) for maximizing ligninolytic enzyme production. Additionally, separation of its lignin peroxidase was conducted. After experiments, an optimized culture medium/condition was constructed (per liter of Kirk's medium): dextrose 10 g, ammonium tartrate 0.11 g, Tween-80 0.5 g, MnSO 4 7 mg, and veratryl alcohol 0.3 g in 10 mM acetic acid buffer pH 4.5. Under the optimized experimental condition, both lignin peroxidase (LiP) and manganese peroxidase (MnP) were detected and reach the highest yield at 30°C on the 8th day culture. Salt precipitation methods was used in the extraction and purification processes. Results show that salt precipitation with 60% (NH 4 ) 2 SO 4 yielded the best result, especially toward LiP. Enzyme separation was conducted and two fractions with LiP activity. LiP1 and LiP2 were produced using three columns sequentially: desalting column, Q FF ion exchange column and Sepharyl S-300 HR gel filtration. LiP1 and LiP2 had been purified by 9.6-and 7.6-fold with a yield of 22.9% and 18.6%, respectively. According to the data of sodium dodecyl sulfate polyacrilamide gel electrophoresis (SDS-PAGE), the molecular weights of the enzymes are 38 kDa and 40 kDa, respectively.

Biosurfactants are useful tools for the bioremediation of contaminated soil: a review

“…These enzymes are secreted during secondary metabolism, as a result of nutrient depletion of carbon or sulphur, or especially, manganese and nitrogen (Hamman et al, 1997;Leung and Pointing, 2002). Other factors are also implicated, such as initial pH of the medium and incubation temperature , the level of aeration and agitation during incubation, the availability of mediator compounds and metals (Leung and Pointing, 2002;Mouso et al, 2003;Cordi et al, 2007), or the presence and concentration of surfactants (Rodríguez Couto et al, 2000;Ürek and Pazarlioğlu, 2005;Wang et al, 2008).…”

Optimization of laccase production in the white-rot fungusPleurotus ostreatus(ACCC 52857) induced through yeast extract and copper

“…[18,19] Aromatic compounds structurally related to lignin, such as xylidine, ferulic acid and veratric acid, are routinely added to fungal cultures to increase laccase production. [12,15,20,21] The regulation of laccase expression by metals is widespread in fungi.…”

Purification and Characterization of Lignin Peroxidase Isozymes from Humicola grisea (Traaen) and Its Application in Bioremediation of Textile Dyes

“…Based on this fact they suggested that certain functional variability is needed; the main additional reason for the splitting in many isoenzymes is thought to be excessive glycosylation. Many researchers reported isoenzymes of multiple LiPs from whiterot fungi species Kirk, 1988 andWang et al, 2008).…”