琵琶甲多糖的提取分离、结构表征及生物活性研究

Study on the Extraction, Separation, Structural Characterization and Biological Activities of Polysaccharides from Blaps Rynchopetera Fairmaire

关键词:  琵琶甲  多糖  单糖组成  相对分子质量  抗氧化  抗炎

Key words:  Blaps rynchopetera Fairmaire  polysaccharides  monosaccharide composition  relative molecular mass  antioxidant  anti-inflammatory

摘要:

目的 研究昆虫琵琶甲多糖的结构表征及生物活性。方法 采用水提醇沉和分级沉淀法制备得琵琶甲粗多糖组分BP50、BP75和BP90，并用葡聚糖凝胶G-75进一步分离纯化BP90得琵琶甲多糖组分BP90-Ⅱ。用苯酚-硫酸法、BCA法、HPLC、凝胶渗透色谱联用多角度激光光散射和示差检测器、红外光谱法分析表征多糖结构特征；测定各组分清除DPPH、ABTS和OH自由基的能力来评估抗氧化活性；此外，采用脂多糖诱导的BV-2小胶质细胞初步研究琵琶甲多糖的抗炎活性。结果 多糖组分BP90的抗氧化能力最强。BP90-Ⅱ的总糖、蛋白质含量分别为82.13%和11.28%。BP90-Ⅱ的红外光谱呈现多糖的典型特征吸收峰，重均分子质量为56 200 g·mol^–1。BP90-Ⅱ是由甘露糖、鼠李糖、氨基葡萄糖、葡萄糖醛酸、半乳糖醛酸、氨基半乳糖、葡萄糖、半乳糖、阿拉伯糖和岩藻糖10种单糖组成的杂多糖，其中葡萄糖含量最高，达74.85%。结果显示琵琶甲多糖BP90-Ⅱ对脂多糖诱导产生的NO有一定的抑制作用，当BP90-Ⅱ浓度为10 μg·mL^–1和100 μg·mL^–1时，NO抑制率分别为(14.86±1.63)%、(36.43±5.62)%。结论 琵琶甲多糖具有良好的抗氧化能力和一定的抗炎活性，具有一定的药用和食用开发价值。

Abstract:

OBJECTIVE To study the structural characteristics and biological activities of the polysaccharides from insect Blaps rynchopetera Fairmaire. METHODS The crude polysaccharide components(BP50, BP75 and BP90) of Blaps rynchopetera Fairmaire were extracted by method of water extraction and alcohol fractional precipitation. BP90 was further isolated and purified by Sephadex G-75 to obtain polysaccharide component(BP90-Ⅱ). Structural characteristics of polysaccharide from Blaps rynchopetera Fairmaire were investigated by using phenol-sulfuric acid method, BCA method, HPLC, gel permeation chromatography coupled with multi-angle laser light scattering detector and reflective index detector, infrared spectrum, respectively. Antioxidant activities of different polysaccharide components were evaluated by scavenging capacity on DPPH, ABTS, and OH free radicals. Additionally, anti-inflammatory effect of polysaccharide from Blaps rynchopetera Fairmaire was tested on lipopolysaccharide-stimulated BV-2 microglia. RESULTS The antioxidant activity showed that BP90 had the strongest antioxidant capacity. The content of total sugar and protein in BP90-Ⅱ was 82.13% and 11.28%, respectively. The infrared spectra of BP90-Ⅱ showed typical absorption peaks of polysaccharide. With a weight-average molecular weight of 56 200 g·mol^-1. The BP90-Ⅱ was composed of mannose, rhamnose, glucosamine, glucuronic acid, galacturonic acid, galactosamine, glucose, galactose, arabinose and fucose, among which the content of glucose was the highest, up to 74.85%. The results showed that BP90-Ⅱ had inhibitory effect on NO production. NO inhibition rate of BP90-Ⅱ at the concentration of 10 μg·mL^-1 and 100 μg·mL^-1 was (14.86±1.63)%, (36.43±5.62)%, respectively. CONCLUSION The polysaccharide from Blaps rynchopetera Fairmaire have significant anti-oxidation ability and certain anti-inflammatory activity. The medicinal and edible value of polysaccharide from Blaps rynchopetera Fairmaire should be developed.