The strain SES28 was isolated from an indoor contaminated agar plate during a screening program for alkaliphilic CM-cellulose-degrading bacteria. It showed a prominent clear hydrolysis of the substrate at pH 10. The 16S rDNA analysis related it to the genus Nocardiopsis. Nocardiopsis sp. SES28 was able to grow at pH values up to 10.5, the major biomass being produced at pH 10, and pH 8 was the optimum for b-1,4-glucanase production. The optimum pH for b-1,4-glucanase activity was 9.0, and it was higher than 60% throughout the pH range 6.5-10.0; showing 94% of its a relative activity at pH 10. The feature of this bacterium to produce b-1,4-glucanase active in a broad pH-range might be useful for detergent-and textile-processing technologies.

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Intracellular alpha-L-rhamnosidase (EC 3.2.1.40) from the psychrotolerant Pseudoalteromonas sp. 005NJ showed a dose-dependent inhibition for L-rhamnose (IC(50) = 20 mM) and D-ribose (IC(50) = 95 mM), whereas D-glucose and L-fucose presented a lower inhibition, with IC(50) values as high as >0.5 and >0.2 M, respectively. On the other hand, D-fructose enhanced enzyme activity threefold, reaching a plateau of maximum specific activity between 0.2 and 0.4 M of this monosaccharide. Both effects, low inhibition and stimulation, caused by key fruit sugars (glucose and fructose), make this biocatalyst an interesting system in terms of its potential application for debittering fruit juices.