Microq tof mass spectrometer

Silica gel plates were purchased from E. Merck (Darmstadt, Germany). Compounds on TLC plates were visualized under UV light. Ethyl acetate extracts were screened by thin layer chromatography (TLC) technique. Pure Compounds were recovered by preparative TLC procedure (system solvent Chloroform/Methanol 8:2 by vol).
Samples for NMR analysis were dissolved in Methanol-d₄. Chemical shifts are reported with the residual MeOD (δ_H 3.32 ppm) as the internal standard for ¹H NMR spectrometry, and MeOD (δ_C 49.0 ppm) for ¹³C NMR spectrometry. 1D- and 2D-NMR spectra were recorded at 600.13 MHz on a Bruker Avance III-600 spectrometer equipped with a TCI Cryo ProbeTM fitted with a gradient along the Z-axis, at a probe temperature of 27°C. ¹³C NMR spectra were recorded on a Bruker avance 400 spectrometer equipped with a Cryo Probe Prodigy (100.62 MHz). ¹H,¹³C NMR, COSY, TOCSY, HSQC, HSQC-EDITED, HMBC (³J: 10 Hz) experiments were used for structural determinations. Mass spectra were acquired on a MicroQ-Tof mass spectrometer coupled with an Alliance HPLC (Waters, Milford, MA, United States) equipped with an ESI positive and negative source.

Total carbohydrate content was determined by Bernfeld ([1955 ]) method using a xylose-based calibration curve. Xylose was determined by D-xylose assay kit (Megazyme), specifically designed to measure this sugar in samples containing up to 5 mg of glucose in the final assay reaction without any interference. Glucose was assayed enzymatically by GOPOD-FORMAT, Megazyme. Protein concentration was determined by the method of Bradford ([1976 (link)]) using bovine serum albumin as the standard. Thermomyces lanuginosus xylanase, (X2753 2500 U/g) was obtained from Sigma. Thermotoga maritima endo-1,4-β-xylanase, 22 U/mg of protein (wheat arabinoxylan at pH 5.0 and 40°C) was obtained from Megazyme.
¹H NMR spectra were recorded at 600.13 MHz on a Bruker DRX-600 spectrometer, equipped with a TCI Cryo Probe TM, fitted with a gradient along the Z-axis. Spectra in D₂O were referenced to internal sodium 3-(trimethyl-silyl)-(2,2,3,3-2H4) propionate (Aldrich, Milwaukee, WI). ¹³C NMR, JMOD-¹H and COSY, TOCSY, HSQC, HSQC-EDITED, HMBC (³ J: 7 and 10 Hz), NOESY (mixing time at 100, 200, 300 msec) experiments were used for structural determination.
Mass spectra were acquired on a microQ-Tof mass spectrometer coupled with an Alliance HPLC (Waters, Milford, MA) equipped with an ESI source.

Carbon, hydrogen, nitrogen, and sulfur (CHNS) were analyzed on a Thermo Electron Corporation FlashEA 1112 CHNS elemental analyzer with autosampler (Thermo Fisher Scientific, Waltham, MA, USA) [53 (link)]. Gas chromatography-mass spectrometry (GC-MS) was carried out by a Polaris Q Ion Trap (Thermo Fisher Scientific, Waltham, MA, USA). Liquid chromatography-mass spectrometry (LC-MS) was performed by a Micro-qToF mass spectrometer (Waters) with electrospray ionization (ESI) source (positive mode) and coupled with a Waters Alliance HPLC system equipped with a C-18 Kromasil column (4.6 × 250 mm, 100 Å, Phenomenex) and by a Q-Exactive Hybrid Quadrupole-Orbitrap spectrometer (Thermo Fisher Scientific, Waltham, MA, USA) with an ESI source and interfaced to an Infinity 1290 UHPLC System (Agilent Technologies) equipped with a Luna 5μ C-18 column (2.0 × 150 mm, 100 Å, Phenomenex). Samples were dried by a Buchi R-200 Rotavapor (Marshall Scientific, Hampton, NH, USA).