Objective: To establish the gel permeation chromatography (GPC) fingerprint chromatograms of polysaccharides in Aloe vera leaf gel from the same habitat (Beijing) and different habitats for evaluating the quality of Aloe vera leaf gel products commercially available and testing common adulterated substances.
Methods: The samples were prepared by water-extraction and alcohol-precipitation method. GPC separation was performed on a Shodex SUGAR KS-805 (300 mm x 8.0 mm, 7 μm) column and a Shodex SUGAR KS-803 (300 mm x 8.0 mm, 6 μm) column at the temperature of 60 degrees C by eluting with 0.1 mol/L NaNO3 (containing 0.2 per thousand NaN) at a flow rate of 0.8 mL/min, the chromatographic effluent was detected by refractive index detector (RID) at the temperature of 50 degrees C.
Results: The common pattern of GPC fingerprint chromatograms was established and four common peaks were demarcated. The similarities of samples from the same habitat (Beijing) and different habitats were over 0.9. Taking the GPC fingerprint chromatograms for the qualified model, three commercially available aloe products were evaluated to be made of Aloe vera by the different manufacturing processes and four common adulterated substances of aloe polysaccharides were identified effectively.
Conclusion: The method is simple and accurate with a good reproducibility, and it can be used for the identification and quality evaluation of Aloe vera leaf gel products.