[Study on quantification method of non-starch polysaccharides in Dendrobium catenatum]

Area of Science:

• Pharmacognosy
• Analytical Chemistry
• Plant Biochemistry

Background:

• Non-starch polysaccharides (NSP), primarily glucomannans, are key bioactive compounds in Dendrobium catenatum.
• Accurate quantification of NSP is essential for evaluating medicinal material quality and guiding production.
• Existing methods may not optimally differentiate NSP from starch in complex plant matrices.

Purpose of the Study:

• To establish and validate a reliable quantification method for non-starch polysaccharides in Dendrobium catenatum stems.
• To compare the proposed method with the official Chinese Pharmacopoeia (2015 edition) method.
• To ensure the method's suitability for quality control and as a reference for other medicinal materials.

Main Methods:

• Dendrobium catenatum C15 strain stems from pear epiphytic cultivation were used.
• Non-starch polysaccharides were extracted via water extraction, α-amylase pretreatment, and single alcohol precipitation.
• Contents of starches, non-starch polysaccharides, and monosaccharides were analyzed, with system suitability testing performed.

Main Results:

• The established method effectively digested starch, retaining non-starch polysaccharides.
• Compared to the Chinese Pharmacopoeia (2015) method, total polysaccharides, glucose, and mannose content decreased by 20.9%, 58.8%, and 1.6%, respectively.
• The analysis results demonstrated accuracy and repeatability.

Conclusions:

• The developed method is suitable for accurate and repeatable content measurement of non-starch polysaccharides in Dendrobium catenatum.
• This method serves as a valuable alternative for the quality control of Dendrobium catenatum.
• It can also be referenced for determining non-starch polysaccharides in other starch-containing medicinal materials.