초록
<P><B>Abstract</B></P> <P>Four marine-derived fungi strains—<I>Penicillium citrinum</I> CBMAI 1186, <I>Aspergillus sydowii</I> CBMAI 934, <I>Aspergillus sydowii</I> CBMAI 935 and <I>Mucor racemosus</I> CBMAI 847—were studied as potential microbial producers of cellulases under solid-state fermentation. The cultivation parameters (time, pH and temperature) and the performance of the cellulases in the hydrolysis of cellulose from sugarcane bagasse were evaluated. The best cultivation time in solid-state fermentation for producing cellulases was 3 days for all of the strains except for <I>A. sydowii</I> CBMAI 934, which exhibited its highest filter paper activity (FPU) after 7 days. After optimizing pH and temperature, activities of 0.73, 1.9, 2.4 and 1.3 FPU g<SUP>−1</SUP> (of substrate) were obtained for <I>A. sydowii</I> CBMAI 935, <I>A. sydowii</I> CBMAI 934, <I>M. racemosus</I> CBMAI 847 and <I>P. citrinum</I> CBMAI 1186, respectively. The hydrolysis of cellulose was studied using rind and pith fractions of sugarcane bagasse, with and without alkali pretreatment. Independent of the fungi strains, untreated bagasse was resistant to saccharification. After the treatment, the degree of saccharification was 78% for <I>A. sydowii</I> CBMAI 934 and 24% for <I>M. racemosus</I> CBMAI 847. The different anatomical and morphological characteristics of the rind and pith cells influenced the saccharification by cellulases for the different marine fungi strains. The hydrolysis by cellulases from <I>A. sydowii</I> CBMAI 934 produced 56% and 81% saccharification in the rind and pith, respectively. This fungus strain exhibits significant potential for the production of fermentable sugars resulting from the hydrolysis of cellulose from sugarcane bagasse, mainly after pretreatment with NaOH solution.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Four marine-derived fungi were achieved for the first time as cellulase producers. </LI> <LI> Different optimum pH and temperature for FPU activity were obtained for each strain. </LI> <LI> <I>Aspergillus sydowii</I> CBMAI 934 performed the saccharification of sugarcane bagasse. </LI> <LI> This is the first report of sugarcane bagasse saccharification by marine-derived fungi. </LI> </UL> </P>