2002-08-012024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/655364摘要：由靈芝所含具有分支的 (1→3)-β-D-葡萄聚糖已知具有免疫調節與抗腫瘤的活性，這類由真菌所得的多醣被歸類為『生理活性調節劑』，巨大分子量與單一葡萄糖基β- (1→6)分支度都是影響活性的表現主要因素。由於分子巨大靈芝多醣水溶液會表現出高黏度且容易聚集成膠體或沉澱，使其在食品與臨床上的應用性受到很大的限制。酵素與超音波降解是常用的方法，用來降低多醣的黏度與分子量，雖然超音波降解對斷裂鍵結的選擇專一性較差，但它卻是較經濟有效的方法。目前大部分相關的研究都針對分子量與黏度的降低做分析，少有對多醣分支探討，因為分支度的分析是一個繁瑣且費時的工作。本計畫的目的是利用超音波處理來降解靈芝多醣，以降低溶液的黏度並提高溶解度與穩定性，並於降解過程檢視免疫刺激活性，多醣分子量與分支度的變化。分支度的分析，會使用本實驗室剛發展的酵素—高效陰離子交換層析法，以取代繁雜的化學甲基化方法。<br> Abstract: The polysaccharides, branched (1→3)-β-D-glucans, of Ganoderma lucidum are known to have potent immune-stimulating and anti-tumor activities. The glucans along with other fungal glucans belongs to the class of substances known as biological response modifiers. The large molecular weight and O-6 linkedβ-glucosyl branches directly affect the activity of the glucans. The preparation and administration for food and clinical uses are difficult because of the high viscosity and high aggregation tendency of its aqueous solution. Enzymatic and ultrasonic depolymerization are common means to reduce the viscosity and to improve the solubility of polysaccharides. The ultrasonic degradation is a more efficient way to reach the goals, although it is less specific on the linkage breaking. Most of studies only focus on the molecular weight or viscosity reduction and overlook the effects on the glucosyl branches, since the assays for the degree of branching are tedious and time consuming. The objects of this project are to employ ultrasonic degradation to degrade theβ-D-glucans of Ganoderma lucidum to reduce the viscosity and increase soluble stability. During the depolymerizing process, the followings will be monitored, the immune- stimulating activities, the molecular weight, the degree of branching, the viscosity and the stability in aqueous solutions. A new enzyme-high performance anion-exchange chromatography technique developed in our laboratory will also be used to determine the degree of branching of the glucans to replace the tedious methylation method.靈芝(1→3)-β-D-聚葡萄糖超音波降解多醣分支度Ganoderma lucidumbranched (1→3)-β-D-glucansultrasonic degradationpolysaccharidesdegree of branching