摘要
利用木瓜蛋白酶水解的蚕蛹蛋白酶解液作为研究原料,根据响应面试验设计方法,以脱色率和1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除保持率作为响应面指标,得最佳脱色工艺条件为:活性白土、碱性钙基膨润土和膨润土按照质量比1∶1∶1混合为脱色剂、脱色剂用量1.9%、酶解液质量浓度9.61 mg/m L、p H 7.2、水浴温度60℃、振荡转速150 r/min、脱色时间1.0 h。在此条件下实验,得出DPPH自由基清除保持率84.5%、脱色率94.5%,与预测值相比误差值均小于5%,说明采用响应面试验设计方法对蚕蛹蛋白酶解液脱色体系进行优化具有较好的可靠性。最后再对脱色前后酶解液中各氨基酸含量进行比较,发现经脱色处理后酶解液中对DPPH自由基抑制有显著作用的疏水性氨基酸和芳香族氨基酸含量减少。
Papain hydrolyzate of silkworm pupae protein with DPPH radical scavenging activity was decolorized by the combined use of activated clay, alkaline Ca-bentonite and bentonite. Based on decolorization efficiency and retention rate of radical scavenging activity, the decolorization conditions were optimized by using single-factor design and central composite design(CCD) coupled with response surface methodology(RSM). When the hydrolyzate with a concentration of 9.61 mg/m L and an initial p H of 7.2 was added with activated clay:alkaline Ca-bentonite:bentonite(1:1:1) in a proportion of 1.9% and incubated for 1.0 h in a thermostatically controlled water at 60 ℃ with shaking at a speed of 150 r/min, it retained 84.5%of its original DPPH radical scavenging activity and the decolorization rate was 94.5%, both close to the predicted values with a relative error less than 5%, suggesting the reliability of the developed response surface model. Comparing the amino acid composition of the decolorized hydrolyzate with that of the untreated one, it was found that the contents of hydrophobic and aromatic amino acids which are significantly effective in inhibiting DPPH free radical were reduced after the decolorization treatment.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2015年第2期12-18,共7页
Food Science
基金
国家自然科学基金青年科学基金项目(31401629)
广西自然科学基金项目(2013GXNSFBA019031)
河池市科学研究与技术开发计划项目(河科攻1489-1-6)
关键词
蚕蛹蛋白
DPPH自由基清除率
脱色
响应面分析
silkworm pupae protein
DPPH radical scavenging rate
decolorization
response surface methodology