3.1. Cellulases. Cellulases convert cellulose to fermentable
sugars fit for human consumption and the largest known
producers are from genus Streptomyces [37]. Cellulases from
Streptomyces sp. are reported to have an alkaline pH optimum
and high thermostability. Subsequently, the enzyme
was used as a supplement in detergents to clean, soften,
and restore the color of the fabrics. It was also tested for
the treatment of textiles, processing of paper and pulp,
and as an animal feed additive [6]. Besides Streptomyces,
several other genera like Thermobifida and Micromonospora
produce recombinant cellulases that can be commercially
exploited [7]. A recombinant cellulase with thermal and
pH stability is reported from Streptomyces thermoviolaceus;
this enzyme retains its activity in the presence of commercial
detergents highlighting its superiority to the existing
commercial cellulases [8]. Cellulase from Thermomonospora
fusca has been used for degradation of cotton and avicel
[9]. These enzymes not only hold a biotechnological
promise but can be economical due to their low cost
of production. Their production can be carried out on
cheap substrates like rice and wheat straw [10] and fruit
peels [38].