Analysis of the chemical stability of Morinda officinalis oligosaccharides during extraction / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the chemical stability of oligosaccharides in Morinda officinalis (M. officinalis) extracted with different solvents. METHODS: The change of M. officinalis oligosaccharides extracted with water, ethanol, and aqueous solutions at different pHs was detected by HPTLC. RESULTS: The oligosaccharides began to constantly hydrolyze after 0.5 h when being extracted with water for different time. There was a fall of oligosaccharides concentration while the contents of fructose and sucrose were on the rise. New unknown compositions were generated after 0.5 h. When M. officinalis oligosaccharides were extracted with different percentages of ethanol, it only hydrolyzed when ethanol was in the range of 10%-30%, with little unknown compositions. Oligose was almost completely hydrolyzed at pH 2-3 but the hydrolyzation was alleviated at pH 3-4, with many kinds of new unknown composition generated. The oligosaccharides became stable when the pH was between 6 and 10. CONCLUSION: M. officinalis oligosaccharides is unstable in water, but rather stable in ethanol. However, there is significant difference in aqueous solutions at different pHs.