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目的 分离纯化白念珠菌胞壁碱溶性β－葡聚糖，并分析其物理化学性质和结构。 方法与结果 白念珠菌标准株 IDC1d经 YEPD培养基 28℃、 18 h培养，收集酵母相细胞， 0.75 mol/L NaOH液提取，乙醇沉淀，得粗多糖。采用红外光谱、苯酚－硫酸法、蒽酮－硫酸法、 3,5－二硝基水杨酸法、考马斯亮蓝法定性分析粗多糖。粗多糖不含还原糖，但含有蛋白质。粗多糖经 Sephadex G－ 200凝胶柱层析纯化。纸层析、凝胶柱层析鉴定所得多糖的纯度，表明其为均一物质。凝胶柱层析测定相对分子质量约为 89 125.09。多糖经完全酸水解，硅胶薄层层析和气相色谱分析单糖组分，结果表明其为 D－葡萄糖聚合成的多糖。红外光谱提示多糖糖苷键为β型。高碘酸氧化和 Smith降解结果表明多糖包含 1→ 3和 1→ 6两种连接键，推测前者为主链键型，后者为支链键型。
Objective To isolate and purify the alkaline-soluble β-glucan of Candida albicans cell wall and analyze its physico-chemical properties and structure. Methods and Results Candida albicans standard strain IDC1d was cultured in YEPD medium at 28 ℃ for 18 h. Yeast cells were collected, extracted with 0.75 mol / L NaOH solution and ethanol precipitated to obtain crude polysaccharide. The crude polysaccharides were analyzed qualitatively by infrared spectroscopy, phenol-sulfuric acid method, anthrone-sulfuric acid method, 3,5-dinitrosalicylic acid method and Coomassie brilliant blue method. Crude polysaccharide does not contain reducing sugars, but contains protein. Crude polysaccharides were purified by Sephadex G-200 gel column chromatography. Paper chromatography, gel column chromatography identified the purity of the resulting polysaccharide, indicating that it is a homogeneous material. The relative molecular mass of the gel column was about 89 125.09. The polysaccharides were analyzed by complete acid hydrolysis, silica gel thin layer chromatography and gas chromatography for monosaccharide composition. The results showed that polysaccharides were polysaccharides synthesized by D-glucose. Infrared spectra indicate that the glycosidic bond of polysaccharide is β type. Periodate oxidation and Smith degradation results showed that the polysaccharides contained 1 → 3 and 1 → 6 two kinds of bonds, suggesting that the former is the main chain and the latter is the branched chain type.