The Antarctic fungus Lecanicillium muscarium CCFEE-5003 was preliminary cultivated in shaken flasks to check its chitinase production on rough shrimp and crab wastes. Production on shrimp shells was much higher than that on crab shells (104.6 +/- 9.3 and 48.6 +/- 13.1 U/L, respectively). For possible industrial applications, bioprocess optimization was studied on shrimp shells in bioreactor using RSM to state best conditions of pH and substrate concentration. Optimization improved the production by 137% (243.6 +/- 17.3). Two chitinolytic enzymes (CHIl and CHI2) were purified and characterized. CHIl (MW ca. 61 kDa) showed optima at pH 5.5 and 45 degrees C while CHI2 (MW ca. 25 kDa) optima were at pH 4.5 and 40 degrees C. Both enzymes maintained high activity levels at 5 degrees C and were inhibited by Fe++, Hg++ and Cu++. CHI2 was strongly allosamidin-sensitive. Both proteins were N-acetyl-hexosaminidases (E.C. 3.2.1.52) but showed different roles in chitin hydrolysis: CHI1 could be defined as "chitobiase" while CHI2 revealed a main "eso-chitinase" activity. (c) 2013 Elsevier Inc. All rights reserved.