米曲霉固态发酵玉米胚芽粕制备玉米肽的研究

Preparation of hydrophobic corn peptides by Aspergillus oryzaer solid-state fermentation

经过单因素试验和正交试验,确定了米曲霉发酵玉米胚芽粕生产玉米多肽的最佳发酵条件:玉米胚芽粕含量为40%(60%麸皮),培养基含水量为74%,培养基接种量为7%,培养温度30℃,发酵时间84h。在此条件下玉米肽转化率达到最大为36%。并对制得的玉米肽进行了初步的分离纯化,经截留分子质量104的中空纤维柱超滤,得到分子质量在104以下的超滤液,超滤液经SephadexG-25柱分离和相对分子质量分布的测定,共洗脱出2个峰。经过计算,其各级玉米肽组分相对分子质量分别大约为5128和1626 Da。为了进一步验证这两种组分的纯度,我们在实验中用Tricine-SDS-PAGE电泳进行了验证,并证明确实主要为两种组分,与葡聚糖凝胶柱分离结果相符。

After a series of single factor and orthogonal experiments,the optimum conditions for preparation of corn peptides by Aspergillus oryzaer ferment corn germ meal were obtained as follows：corn germ meal 40%（bran 60%）,medium moisture content 74%,medium inoculation content 7%,fermentation temperature 30℃,fermentation time 84h.Under these conditions,the maxium conversion rate of corn peptides was about 36%.Separation and purification of preliminarily corn peptides were obtained by ultrafilrate（molecular mass 104） and Sephadex G-25.Two peaks were eluted and their molecular weight are around 5128 and 1626 Da after calculation.In order to identify the purity of the two components,Tricine-SDS-PAGE was used in the experiment.The results were consistent with the results that obtained before.