Functions of Glucan

Glucans have an important role in biomedical applications. Glucans can replace a portion of whole blood during blood transfusion as a plasma volume expander. Glucans can also activate macrophages and neutrophilic white blood cells, etc. It can increase the content of leukocytes, cytokinin, and special antibodies, and comprehensively stimulate the immune system. In addition, gels made of dextran are often used for biochemical separations, such as column chromatography. A chemically modified dextran obtained by fermentation of sucrose has a cross-linked mesh structure in its molecules, which can be used as a molecular sieve to separate low molecular weight compounds from high molecular weight compounds.

Fig.1 Structure of glucan. (CD BioGlyco)

Glucan Analysis Service at CD BioGlyco

CD BioGlyco offers analytical testing solutions for a wide range of Polysaccharides.

First of all, we offer the following services in testing the content of glucan:

• Viscosity method
  The principle is that the viscosity of barley extracts is mainly produced by β-glucan. In addition, the viscosity of glucan is also related to the molecular weight. If the glucan content is the same, the molecular weight of the larger molecular weight produces greater viscosity.
• Precipitation
  The principle is to use specific salts or organic solvents to precipitate dextran.
• Enzymatic method
  We use a specific β-glucan endonuclease to obtain oligosaccharides, which are acid-decomposed and then used to determine the glucose content using glucose oxidase/peroxidase reagents. This method is also capable of determining the content of reducing sugars. In addition, we offer cellulase enzyme determination of β-glucan content in grains.
• Fluorescence method
  The method mainly utilizes the property that fluorescent substances bind specifically to β-glucan. This method is easy to operate and can be used for the determination of large quantities of samples.
• Congo red method
  According to the high specificity of Congo red binding with β-glucan, Congo red is added into the sample solution, and the absorbance is measured after a certain time of accurate reaction at a certain temperature, and the content of β-glucan in the sample is known according to the standard curve of β-glucan.

Secondly, for the structure testing of glucan, we offer the following determination services:

• Spectrophotometric
  This method is suitable for all kinds of substances in the glucan. It determines the test of water-soluble polysaccharides with a molecular weight of 1×10⁴ or more.
• Nuclear magnetic resonance (NMR)
  This method is an important method for determining the structure of glucan. In the ¹³C NMR spectra, the class and configuration of the sugar are determined based on the displacement of the end group carbon.
• Fourier-transform infrared spectroscopy (FT-IR)
  Based on the position of the characteristic absorption peaks in the spectrum, we easily determine the conformation of the glucan (in general, the presence of a single peak near 890 cm^-1 indicates that the dextran is a β-glucan).

Fig.2 Analytical procedure of glucan. (CD BioGlyco)

Case Study

Background

Glucans are widespread glucose polymers that serve essential structural and storage functions across plants, fungi, algae, and grains. They are broadly categorized into α-glucans (such as starch and glycogen) and β-glucans (critical components of fungal cell walls and dietary fibers), each exhibiting vastly different bioactivities and industrial applications. In sectors like functional food development, immunology, and biofuel engineering, determining the precise ratio of α- to β-glucans within a single matrix is crucial. However, due to their structural similarities and the overlapping solubility of various cell wall polysaccharides, traditional chemical colorimetric assays frequently suffer from cross-interference and low sensitivity, failing to deliver accurate subtype separation.

Our Solution

CD BioGlyco addressed this analytical bottleneck by deploying an optimized, high-performance method utilizing Parallel sequential hydrolysis coupled with HPAEC-PAD. This refined workflow was adapted from industry-standard enzymatic assay principles and enhanced with multiple in-house optimizations.

• Total Glucan Depolymerization: To establish the absolute baseline, one sample aliquot underwent concentrated acid hydrolysis (H₂SO₄) followed by fine-tuned synergistic enzymatic digestion (using high-activity exo-1,3-β-glucanase and β-glucosidase). This ensured the complete breakdown of all glucan frameworks into glucose monomers.
• Selective α-Glucan Extraction: In a strictly parallel assay, a second sample aliquot was treated with a cocktail of highly specific α-glucan-degrading enzymes. This step selectively cleaved starch and other α-linked glucose polymers into monomeric units while leaving the resilient β-glucan backbone entirely intact..
• High-Sensitivity HPAEC-PAD Quantification: The liberated glucose pools from both pathways were directly quantified using our advanced HPAEC-PAD system. This system provides superior resolution and direct, non-derivatized electrochemical detection of carbohydrates with picomole-level sensitivity.
• Rigorous Quality Control: To validate analytical consistency and enzyme efficiency across every analytical batch, a well-characterized yeast β-glucan reference standard was concurrently analyzed as a positive control.

Results

By leveraging the specific chemical data acquired from the parallel analytical streams, the absolute $\beta$-glucan matrix was accurately resolved using a standardized substraction matrix:

β-Glucan = Total Glucan - α-Glucan

Table 1 Glucan content. (CD BioGlyco)

The final deliverable provided the client with a comprehensive glucan result detailing the exact absolute content (expressed in mass percentage %) of total glucans, α-glucans, and β-glucans. By the ultra-high accuracy and baseline resolution of the HPAEC-PAD method, this optimized assay successfully eliminated matrix background noise. The high-fidelity dataset provided the client with definitive molecular evidence required for functional labeling and proclinical-grade immunomodulator quality control workflows.

Publication

Paper Title: Structure analysis of β-glucan in barley and effects of wheat β-glucanase

Technology: Enzymatic determination of glucan

Journal: Journal of Cereal Science

IF: 3.8

Published: 2019

Results: The structure of β-glucan as a whole was determined based on the distribution of oligosaccharides released from β-glucan in the three fractions after digitonin digestion. The β-glucan fragments were analyzed using principal component analysis (PCA). The variable DP3/DP4 mainly contributed to the first principal component, while fragments with DP ≥ 5 and sum DP5+DP6 were explained by the second principal component with DP5+DP6 being the most influential variable. In the scores plot a specific clustering was observed as the water extractable β-glucans of variety Karmose, SW 28708, and SLU 7 were found in the upper left quarter of the plot. β-Glucan quantification was performed on the water-insoluble fraction (WU) and on the fraction "WU-WhE-Ins" to highlight the proportion of β-glucan released in the supernatant by the wheat enzymes, given by the difference calculated between the amount of β-glucan in the two fractions The results showed that from the insoluble population of β-glucan 52.3% was released in variety SLU 7, 45.3% in Gustav and 44.1% in SW 28708.

Applications

• The glucan analysis can be used to study the regulation of human immunity.
• The glucan analysis is used in the research and development of anti-cancer drugs.
• The glucan analysis can be used in the development of cholesterol-lowering and blood-sugar-lowering drugs.

Advantages

• We have many types of methods in the analysis of carbohydrates and provide clients with comprehensive glucan analysis services.
• We have a powerful solution to provide clients with one-stop glucan analysis services including production, isolation, purification, and performance analysis.
• Our analytical services provide the ability to test a large amount of glucan at the same time, which greatly saves the researcher's time.

CD BioGlyco has a professional research team and world-leading experimental capabilities with many years of experience in glucan research. We help our clients to solve the problems of glucan research as much as possible. If you are interested in our services, please feel free to contact us.