Cellulases are a complex group of enzymes which are secreted by a broad range of microorganisms including fungi, bacteria, and actinomycetes. In the natural environment, synergistic interactions among cellulolytic microorganisms play an important role in the hydrolysis of lignocellulosic polymer materials. In fact, it is the combined action of three major enzymes which determines the efficiency of this process. They are exoglucanases, endoglucanases, and β-glucosidase. Microorganisms produce these enzymes in a diverse nature which determines their efficiency in cellulose hydrolysis. During the cellulose degradation reaction, the enzyme targets the β-1,4-linkages in its polymeric structure. This is an essential ecological process as it recycles cellulose in the biosphere. The application of this same scenario for industrial purposes is identified as an emerging area of research. Biofuel production, textile polishing and finishing, paper and pulp industry, and lifestyle agriculture are among the key areas where cellulase enzyme shows a broader potential. The objective of this chapter is to discuss the structure, function, possible applications, as well as novel biotechnological trends of cellulase enzymes. Furthermore, possible low-cost, enzymatic pretreatment methods of lignocellulosic material in order to use it as an efficient raw material for biofuel production will be discussed.

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Sri Lanka is rich in biological diversity, but its fungal diversity is not adequately studied and documented. Recent fungal diversity estimations have predicted that the tropical regions would harbour a large number of novel fungal species. Fungi are ubiquitous, hence it is important to carry out proper investigations to discover novel taxa in different habitats and ecosystems. These taxa represent different life modes i.e. pathogens (of plants, animals and humans), saprobes, endophytes, symbionts (lichens, mycorrhizae), and lichenicolous. Current mycology is mainly based on polyphasic approaches (morphological, DNA based and chemical analyses) to define the species (consolidated species concept). DNA based phylogenetic analyses are widely used in higher level classification. These DNA are mainly extracted from cultures. Depositing a specimen that the fungus is present at a reputed Fungarium and depositing a culture resulted from the specimen at a reputed culture collection is important. The “International Code of Taxonomy of Nomenclature for algae, fungi and plants” stated that it is important to deposit the holotype at a reputed fungarium, while depositing the ex-type culture which is derived from the holotype at a reputed culture collection is also essential. Besides species identification and classification, these specimens and cultures are important in future studies and in genetic resource conservation. In Sri Lanka, currently a national fungarium and a culture collection for fungi do not exist. However, several institutional collections and personal collections are available. In this conceptual paper, we propose to establish a central, national fungarium to deposit holotypes and a culture collection to deposit ex-type cultures while maintaining several regional or mirror collections to replicate the specimens as isotypes and paratypes, and cultures as ex-isotypes and ex-paratypes.