Yim Joung Han, Kim Sung Jin, Ahn Se Hun, Lee Hong Kum
Korea Polar Research Institute, KORDI, Ansan P.O. Box 29, Ansan, Seoul 425 600, South Korea.
Bioresour Technol. 2007 Jan;98(2):361-7. doi: 10.1016/j.biortech.2005.12.021. Epub 2006 Feb 10.
The flocculating activity of an exopolysaccharide, p-KG03, produced by a marine dinoflagellate Gyrodinium impudicum KG03 was investigated. The p-KG03 was a highly sulfated exopolysaccharide that showed strong antiviral activity against encephalomyocarditis virus (EMCV) and immunostimulating activity by NK cell activation. For the industrial applications of p-KG03, as the bioflocculant agent, p-KG03 showed that more than 90% of the flocculating activity in kaolin suspension occurred at concentrations of 0.5 mg/l with the maximum at 1.0 mg/l. However, flocculation decreased from 2.5 mg/l. The flocculation rate increased linearly with concentration and was higher than that observed in commercial products such as polyacrylamide (approximately 1.0 mg/l) or zooglan (approximately 3.0 mg/l). The p-KG03 was an effective flocculant under acidic conditions (pH 3-6) and over a wide temperature range (4-90 degrees C). The presence of cations did not enhance flocculating activity. The average molecular mass, as determined by gel filtration chromatography, was about 1.87 x 10(3) KDa. Galactose was the main sugar in p-KG03, which also contained uronic acid (2.9%, w/w) and sulfate groups (10.3%, w/w). The infrared spectrum of p-KG03 showed absorption bands of carboxylate groups. Thermogravimetric analysis indicated a degradation temperature (T(d)) of 250 degrees C. Several other properties of p-KG03 such as intrinsic viscosity, the rheological behavior, consistency index (k) and flow behavior index (eta) were also studied.
对海洋甲藻裸甲藻KG03产生的一种胞外多糖p-KG03的絮凝活性进行了研究。p-KG03是一种高度硫酸化的胞外多糖,对脑心肌炎病毒(EMCV)表现出强大的抗病毒活性,并通过自然杀伤细胞激活表现出免疫刺激活性。对于p-KG03作为生物絮凝剂的工业应用,p-KG03在高岭土悬浮液中,浓度为0.5 mg/l时絮凝活性超过90%,在1.0 mg/l时达到最大值。然而,浓度从2.5 mg/l起絮凝作用下降。絮凝率随浓度呈线性增加,且高于聚丙烯酰胺(约1.0 mg/l)或菌胶团(约3.0 mg/l)等商业产品。p-KG03在酸性条件(pH 3 - 6)和较宽温度范围(4 - 90℃)下是一种有效的絮凝剂。阳离子的存在并未增强絮凝活性。通过凝胶过滤色谱法测定的平均分子量约为1.87×10³ kDa。半乳糖是p-KG03中的主要糖类,其还含有糖醛酸(2.9%,w/w)和硫酸基团(10.3%,w/w)。p-KG03的红外光谱显示有羧酸盐基团的吸收带。热重分析表明降解温度(T(d))为250℃。还研究了p-KG03的其他一些性质,如特性粘度、流变行为、稠度指数(k)和流动行为指数(η)。