*3.8. TLC and ESI-MS Analysis of the Degradation Products of AlgNJ-07*

To investigate the degradation pattern of AlgNJ-07, the reaction mixtures (800 μL) containing 1 μg purified enzyme and 2 mg substrates (sodium alginate and polyM) were incubated at 30 ◦C for 0–48 h. The hydrolysis products were analyzed by TLC as above. To further determine the composition of the products, ESI-MS was used. The supernatants (2 μL) were loop-injected to an LTQ XL linear ion trap mass spectrometer (Thermo Fisher Scientific, Waltham, MA, USA) after centrifugation. Samples were introduced by direct infusion into the electrospray ionization source (ESI) and mass spectra (MS)

were collected. To help elucidate the structure of the ESI-MS peaks, the MS spectra were collected concurrently by isolating specific *m*/*z* anions, and the oligosaccharides were detected in a negative-ion mode using the following settings: ion source voltage, 4.5 kV; capillary temperature, 275–300 ◦C; tube lens, 250 V; sheath gas, 30 arbitrary units (AU); and scanning the mass range, 150–2000 *m*/*z*.
