Rapid structural characterization and analysis of Cistanche deserticola polysaccharides based on carbohydrate microarray technology

Carbohydrate microarray enabled rapid profiling of CDPs glycan epitopes. • Glucan-related epitopes were identified as the main detectable signals in CDPs. • Conventional structural analyses supported the microarray findings. To address the technical bottlenecks of conventional structural analysis for Cistanche deserticola polysaccharides (CDPs), including cumbersome operation, lengthy detection cycles and low throughput in structural screening, this study introduced carbohydrate microarray technology as a rapid epitope-profiling tool for the structural characterization of CDPs. With C. deserticola as the raw material, we prepared polysaccharide samples via six extraction methods and constructed a tailored carbohydrate microarray system. Specific carbohydrate-binding proteins (BS-400-2, BS-400-3, LM18, LM19, and LM21) were adopted to achieve high-throughput profiling of probe-recognizable polysaccharide epitope features. The reliability and applicability of this technology were evaluated and supported by determining polysaccharide yield, total sugar content, molecular weight ( M w) and monosaccharide composition using conventional analytical methods. Under the established carbohydrate microarray assay conditions, CDPs mainly exhibited BS-400-2-recognizable glucan-related epitope features, whereas obvious binding signals for the selected pectin- and mannan-related epitopes were not observed. Extraction processes markedly influenced the yield and structural characteristics of polysaccharides: ultrasonication-assisted alkaline extraction (UAAIE) achieved the highest polysaccharide yield (13.43%), while microwave-assisted extraction (MAE) produced polysaccharides with the highest total sugar content (85.72%) and M w (7.819 × 10 6  Da). The microarray results were generally consistent with those obtained by conventional methods, supporting the reliability of the carbohydrate microarray-based epitope profiling strategy. Furthermore, the binding performance and specificity of selected probes were examined using structurally defined homogeneous polysaccharides for system optimization, which supports the extended application of this method in other TCM polysaccharides. This rapid carbohydrate microarray system establishes a high-throughput and microscale approach for epitope-level characterization of CDPs, and lays an experimental foundation for the standardized application of carbohydrate microarrays in TCM polysaccharide research. The multi-target strategy can be further extended to other TCM polysaccharides, facilitating subsequent studies on their structure-activity relationships and high-efficiency bioactivity screening. Download: Download high-res image (121KB) Download: Download full-size image