Peculiarities of Pycnoporus species for applications in biotechnology

The genus Pycnoporus forms a cosmopolitan group of four species belonging to the polyporoid white-rot fungi, the most representative group of homobasidiomycetes causing wood decay. Pycnoporus fungi are listed as food- and cosmetic-grade microorganisms and emerged in the early 1990s as a genus whose biochemistry, biodegradation and biotechnological properties have since been progressively detailed. First highlighted for their original metabolic pathways involved in the functionalization of plant cell wall aromatic compounds to yield high-value molecules, e.g. aromas and antioxidants, the Pycnoporus species were later explored for their potential to produce various enzymes of industrial interest, such as hydrolases and oxidases. However, the most noteworthy feature of the genus Pycnoporus is its ability to overproduce high redox potential laccase-a multi-copper extracellular phenoloxidase-as the predominant ligninolytic enzyme. A major potential use of the Pycnoporus fungi is thus to harness their laccases for various applications such as the bioconversion of agricultural by-products and raw plant materials into valuable products, the biopulping and biobleaching of paper pulp and the biodegradation of organopollutants, xenobiotics and industrial contaminants. All the studies performed in the last decade show the genus Pycnoporus to be a strong contender for white biotechnology. In this review, we describe the properties of Pycnoporus fungi in relation to their biotechnological applications and potential.