Guar gum is known to carry out physiological effects such as suppressing the rise in blood sugar level, cholesterol-lowering effect, etc. In USP, the method of content of galactomannan, and ratio of constituting mannose and galactose is defined. According to the USP method, a column packed with L22 should be used and it is necessary for the system suitability to satisfy the following. It was confirmed that the all conditions were satisfied when analyzed using SUGAR SP0810, a column for sugar analysis.
System suitability
| 1. Resolution (System suitability solution) | |
|---|---|
| between Dextrose (= Glucose) and Xylose | ≥ 0.9 |
| between Xylose and Galactose | ≥ 1.0 |
| between Galactose and Mannose | ≥ 1.5 |
| 2. Tailing factor (Standard solution) | |
| Galactose and Mannose peaks | 0.8-1.8 |
| 3. Relative standard deviation (Standard solution) | |
| Galactose and Mannose peaks | ≤ 2.0% (repeated six times) |
Sample Solution A : Guar gum is dissolved in TFA aq. Mannose and glucose are produced as a result of hydrolysis of galactomannan by acids. The content of galactomannan and ratio of constituting mannose and galactose from the quantitative values of mannose and galactose in the portion of guar gum taken were calculated.
Sample Solution B : Guar gum is dissolved in the eluent. No presence of galactose and mannose peaks are observed in the chromatogram of Standard solution B.
Sample : 10μL
System suitability solution : Glucose, Xylose, Galactose, Mannose 5mg/mL each (in H2O)
Standard solution : Galactose, Mannose 10 mg/mL each (in H2O)
Sample Solution A : Guar gum 25mg/mL (prepared according to USP method)
Sample Solution B : Guar gum 5mg/mL (in eluent)
Column : Shodex SUGAR SP0810 (8.0mmI.D. x 300mm) Eluent : H2O Flow rate : 0.75mL/min Detector : Shodex RI Column temp. : 80℃
