U. S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Biobased and Other Animal Coproducts Research Unit, Wyndmoor, PA 19038, USA.
Appl Biochem Biotechnol. 2012 Mar;166(5):1203-14. doi: 10.1007/s12010-011-9505-7. Epub 2011 Dec 23.
Synthetic polymeric flocculants are used extensively for wastewater remediation, soil stabilization, and reduction in water leakage from unlined canals. Sources of highly active, inexpensive, renewable flocculants are needed to replace synthetic flocculants. High kaolin flocculant activity was documented for bovine blood (BB) and blood plasma with several anticoagulant treatments. BB serum also had high flocculant activity. To address the hypothesis that some blood proteins have strong flocculating activity, the BB proteins were separated by SEC. Then, the major proteins of the flocculant-active fractions were separated by SDS-PAGE. Identity of the major protein components was determined by tryptic digestion and peptide analysis by MALDI TOF MS. The sequence of selected peptides was confirmed using TOF/TOF-MS/MS fragmentation. Hemoglobin dimer (subunits α and β) was identified as the major protein component of the active fraction in BB; its high flocculation activity was confirmed by testing a commercial sample of hemoglobin. In the same manner, three proteins from blood plasma (fibrinogen, γ-globulin, α-2-macroglobulin) were found to be highly active flocculants, but bovine serum albumin, α-globulin, and β-globulin were not flocculants. On a mass basis, hemoglobin, γ-globulin, α-2-macroglobulin were as effective as anionic polyacrylamide (PAM), a widely used synthetic flocculant. The blood proteins acted faster than PAM, and unlike PAM, the blood proteins flocculants did not require calcium salts for their activity.
合成聚合物絮凝剂广泛用于废水修复、土壤稳定和减少无衬砌运河的水渗漏。需要寻找高活性、低成本、可再生的絮凝剂来替代合成絮凝剂。有研究证明牛血（BB）和经几种抗凝处理的血浆具有很高的絮凝剂活性。BB 血清也具有很高的絮凝剂活性。为了验证某些血液蛋白具有很强的絮凝活性这一假设，通过 SEC 对 BB 蛋白进行了分离。然后，通过 SDS-PAGE 对絮凝活性组分中的主要蛋白质进行了分离。通过胰蛋白酶消化和 MALDI-TOF MS 肽分析确定主要蛋白质成分的身份。通过 TOF/TOF-MS/MS 片段分析确定了选定肽的序列。血红蛋白二聚体（亚基α和β）被鉴定为 BB 中活性组分的主要蛋白质成分；通过测试血红蛋白的商业样品证实了其高絮凝活性。同样，从血浆中发现了三种具有高絮凝活性的蛋白质（纤维蛋白原、γ-球蛋白、α-2-巨球蛋白），但牛血清白蛋白、α-球蛋白和β-球蛋白不是絮凝剂。就质量而言，血红蛋白、γ-球蛋白、α-2-巨球蛋白与广泛使用的合成絮凝剂阴离子聚丙烯酰胺（PAM）一样有效。血液蛋白的作用速度比 PAM 快，与 PAM 不同的是，血液蛋白絮凝剂不需要钙盐就能发挥作用。
