The degradation products of the FBS of strain A3 towards L. japonica piece and L. japonica roots were identified by high-resolution LTQ-Orbitrap-MS (Thermo, USA) in the negative-ion mode. The source voltage and capillary temperature were set at 3.6 kV and 275 °C, respectively. The mass acquisition range was 160–1500 m/z or 200–1500 m/z.
The AOs composition in the L. japonica root hydrolysate produced by the FBS of strain A3 was analyzed by HPLC on a Superdex Peptide 10/300 GL column (GE Healthcare, USA) [45 (link)]. The AOs in the hydrolysate were eluted with 0.2 M NH4HCO3 at a flow rate of 0.3 ml/min and detected by a UV detector at 210 nm. The commercial saturated mannoronate oligomers were taken as the standards. The proportion of each AO was calculated according to the percentage of the AO area to the total chromatograph area of the AOs [46 (link)].
Total sugar content of the degradation products was measured by the phenol–sulfuric acid method [47 (link)] usingd -glucuronic acid as the standard. The content of uronic acid in the degradation products was analyzed by the sulfamate/m-hydroxydiphenyl assay described by Filisetti-Cozzi [37 (link)] using d -glucuronic acid as the standard.
The AOs composition in the L. japonica root hydrolysate produced by the FBS of strain A3 was analyzed by HPLC on a Superdex Peptide 10/300 GL column (GE Healthcare, USA) [45 (link)]. The AOs in the hydrolysate were eluted with 0.2 M NH4HCO3 at a flow rate of 0.3 ml/min and detected by a UV detector at 210 nm. The commercial saturated mannoronate oligomers were taken as the standards. The proportion of each AO was calculated according to the percentage of the AO area to the total chromatograph area of the AOs [46 (link)].
Total sugar content of the degradation products was measured by the phenol–sulfuric acid method [47 (link)] using
Free full text: Click here
