Pa1 4 50 mm guard column

Cellooligosaccharides separation and detection in the medium and intracellular compartment was done by high-performance anion-exchange chromatography. The induction experiment was repeated using cellooligosaccharides as inducers and sampling was carried out after 1, 3, 5, and 7 h. For intracellular detection, the biomass was collected after 1 h, dried in a towel, grounded by liquid nitrogen, and washed with 5 mL water. Then, it was boiled for 10 min, followed by centrifugation (10,000 rpm, 10 min) and the supernatant was labeled as fraction A. The pellet was resuspended in 3 mL water, boiled for 4 h, and centrifuged. The resulting supernatant was labeled as fraction B. All samples were analyzed by Dionex ICS-5000 (Thermo Fisher Scientific, Waltham, MA, United States) with a pulsed amperometric detector equipped with a disposable electrochemical gold electrode, using a CarboPac PA1 4 × 250 mm analytical column and a CarboPac PA1 4 × 50 mm guard column, at 30°C.

Xylooligosaccharides in the medium were separated by high-performance anion-exchange chromatography (HPAEC), after 1, 3, and 7 h of induction with different oligosaccharides. Upon repeating the experiment, the culture filtrates were analyzed by Dionex ICS-5000 system (Thermo Scientific, Waltham, MA USA) with a pulsed amperometric detector equipped with a disposable electrochemical gold electrode, using a CarboPac PA1 4 × 250 mm analytical column and a CarboPac PA1 4 × 50 mm guard column, at 30 °C.
The presence of xylooligosaccharides inside the cells after 1 h of induction with different oligosaccharides was measured by the same system. The culture was vacuum-filtered, and the towel-dried biomass was ground immediately in liquid nitrogen, washed with 5 mL water, boiled for 10 min, and centrifuged. The supernatant was aspirated to a separate tube and labeled as fraction A. Separately, 3 mL water was added to the precipitated biomass, which was then boiled for 4 h and the ensuing supernatant was labeled as fraction B.