雨生红球藻中蛋白的结构和功能特性研究

Study on the Structure and Functional Characteristics of Proteins from Haematococcus pluvialis

以提取完虾青素的雨生红球藻残渣粉为原料,通过碱提酸沉法制备雨生红球藻蛋白,对雨生红球藻蛋白结构进行表征,研究p H和离子强度对雨生红球藻蛋白功能特性的影响。结果表明,雨生红球藻蛋白的等电点为4.2,亚基分子量分布在14.4、18.4、38 kDa附近,二级结构中α-螺旋、β-折叠、β-转角、无序结构的含量分别为14.86%、18.47%、40.3%、26.37%,含有人体所需必需氨基酸7种,占氨基酸总含量的36.38%。微观结构观察显示雨生红球藻蛋白呈杆状及片状,表面粗糙多孔。随着pH的增加,雨生红球藻蛋白的溶解度、吸水性、乳化性、起泡性及泡沫稳定性呈先增大后减小的趋势,乳化稳定性则呈相反趋势;随着Na Cl浓度的增加,雨生红球藻蛋白的起泡性及泡沫稳定性、乳化性及乳化稳定性均呈先增大后减小的趋势,溶解性则呈先减小后增大再减小的趋势。

Haematococcus pluvialis residue powder,which has been extracted with astaxanthin,was used as the raw material to prepare Haematococcus pluvialis protein by alkaline extraction and acid precipitation method.The protein structure of Haematococcus pluvialis was characterized,and the effects of pH and ion strength on the functional characteristics of Haematococcus pluvialis protein were studied.The results showed that the isoelectric point of Haematococcus pluvialis protein was 4.2.The molecular weight of the subunit was around 14.4,18.4 and 38 kDa,respectively and the content ofα-helix,β-fold,β-corner and disordered structure in the secondary structure was 14.86%,18.47%,40.3%and 26.37%,respectively.It contained 7 kinds of essential amino acids required by the human body,accounting for 36.38%of the total amino acid content.Microscopic observation showed that the protein of Haematococcus pluvialis was rod-shaped and sheet-like,with a rough and porous surface.With the increase of pH,the solubility,water absorption,emulsion capability,foam stability and foam stability of the protein of Haematococcus pluvialis increased first and then decreased,while the emulsification stability showed the opposite trend.With the increase of NaCl concentration,the foam capability,foam stability,emulsion capability and emulsification stability of the protein of Haematococcus pluvialis increased first and then decreased,while the solubility showed a trend of first decreasing,then increasing,and then decreasing again.