Chitin is obtained in industrial scale from shrimps and
crustaceans in general (Yanga et al., 2000). However, the
chrysalides of the silkworm are an alternative source of chitin
and, consequently, of chitosan (Zhang et al., 2000). These
chrysalides are the adult form of the larvae responsible for the
production of the silk thread, and the chrysalides itself
constitute a by-product from the silk industry, which is of
low price and easily available. China and Brazil are the
principal exporting countries of cocoons and raw silk (Table 1),
and the Chinese silkworm (Bombyx mori) has been used in
commercial silk production for centuries (Dingle, 2000).