Studies were carried out with Cunninghamella elegans UCP/WFCC 0542 to evaluate the effects of an abundant supply of amino acids, asparagine and corn steep liquor associated with sucrose on the production of biomass and chitosan by submerged fermentation. The concentrations of the components of the culture medium which were determined by a 2 3 full factorial design evaluated the interactions and effects of the independent variables of the sucrose, asparagine and corn steep liquor in relation to carbon and nitrogen sources, on the production of chitosan regarding biomass. The best results were observed at the central point [asparagine 0.025%, sucrose 0.15% and 0.45% of corn . The crystallinity index of chitosan was 60.92%, and its degree of deacetylation was 75.25%. A low percentage of a supply of sucrose and asparagine with corn steep liquor offered higher yields of biomass and chitosan production at low cost.

ABSTRACT. The production of biofertilizers from rocks increases nutrients for plant nutrition without environmental pollution. The aim of this study was to evaluate the effectiveness of biofertilizers from phosphate and potassium rocks mixed with organic matter (earthworm compound) inoculated with free living diazotrophic bacteria (NFB 10001) and Cunninghamella elegans (fungus with chitosan) on yield, characteristics, and nutrient uptake of banana (cv. Williams), and attributes of a Red Yellow Argisoil of the rainforest Zone of Pernambuco, Brazil. The experimental design included two biofertilizers: (a) PK rock biofertilizers plus organic matter (NPKB) and (b) bioprotector (NPKP) applied at 50, 100 and 150% of the recommended rate for banana, which were compared with soluble mineral fertilizers (NPKF) applied at the recommended rate, and earthworm compound (20 ton ha -1 ). The best results of the plant parameters were obtained with NPKB and NPKP applied at the highest rates (150% RR). A normal yield was produced when NPKB and NPKP were applied at the highest rates and NPKF at the recommended rate. The available P and K in the soil showed a significant fertilization effect, especially when NPKB and NPKP were applied at the highest rates. The biofertilizer and bioprotector may be alternatives to mineral soluble fertilizers.