초록
<P>In this study, we designed and evaluated a microalgal pretreatment method using cellulolytic bacteria that naturally degrades microalgae in their native habitat. Bacterial strains were isolated from each of two mollusk species in a medium containing 1% carboxymethyl cellulose agar. We selected nine bacterial strains that had endoglucanase activity: five strains from <I>Mytilus chilensis</I>, a Chilean mussel, and four strains from <I>Mesodesma donacium</I>, a clam found in the Southern Pacific. These strains were identified phylogenetically as belonging to the genera <I>Aeromonas</I>, <I>Pseudomonas</I>, <I>Chryseobacterium</I>, and <I>Raoultella</I>. The cellulase-producing capacities of these strains were characterized, and the degradation of cell walls in <I>Botryococcus braunii</I> and <I>Nannochloropsis gaditana</I> was tested with “whole-cell” cellulolytic experiments. <I>Aeromonas bivalvium</I> MA2, <I>Raoultella ornithinolytica</I> MA5, and <I>Aeromonas salmonicida</I> MC25 degraded <I>B. braunii</I>, and <I>R. ornithinolytica</I> MC3 and MA5 degraded <I>N. gaditana</I>. In addition, <I>N. gaditana</I> was pretreated with <I>R. ornithinolytica</I> strains MC3 and MA5 and was then subjected to an anaerobic digestion process, which increased the yield of methane by 140.32% and 158.68%, respectively, over that from nonpretreated microalgae. Therefore, a “whole-cell” cellulolytic pretreatment can increase the performance and efficiency of biogas production.</P>