摘要
[目的]本试验旨在研究丙二醛(MDA)对豆粕蛋白质氧化的影响以及茶多酚(TP)的缓解作用。[方法]将新鲜豆粕分为8个处理组,分别采用0、0.1、1、10 mmol·L^(-1)MDA和0、0.1、1、10 mmol·L^(-1)MDA+0.6 mg·mL^(-1)TP进行处理,测定豆粕中的羰基、巯基、氨基酸含量等指标。[结果]随着MDA浓度的升高,豆粕中羰基含量逐渐增加(P<0.05),巯基、总巯基基团、蛋氨酸、酪氨酸和赖氨酸含量和豆粕蛋白质体外消化率逐渐降低(P<0.05),色氨酸内源荧光强度呈先升高后降低趋势,内源荧光λmax逐渐发生蓝移,且席夫碱荧光强度逐渐升高。与对照组相比,当MDA浓度达1 mmol·L^(-1)时,豆粕羰基含量显著增加(P<0.05),巯基和总巯基基团含量显著降低(P<0.05),豆粕蛋白质体外消化率均极显著降低(P<0.01);MDA浓度达10 mmol·L^(-1)时,豆粕羰基含量极显著增加(P<0.01),豆粕巯基和总巯基基团含量及蛋白质体外消化率均极显著降低(P<0.01);而豆粕中的蛋氨酸、酪氨酸和赖氨酸含量均极显著降低(P<0.01)。添加TP可减缓豆粕羰基含量的增加、巯基和总巯基基团含量的减少、蛋氨酸含量的减少、蛋白质体外消化率的下降、豆粕中色氨酸内源荧光强度的降低和席夫碱生成量的增加。[结论]1 mmol·L^(-1)丙二醛可引起豆粕中的蛋白质氧化,造成豆粕蛋白质结构发生较大改变,蛋白质体外消化率下降,茶多酚则可有效缓解丙二醛诱导的豆粕蛋白质氧化及其体外消化率的下降。
[Objectives]This experiment was conducted to study the effects of malondialdehyde(MDA)on protein oxidation of soybean meal and the alleviation of tea polyphenols(TP).[Methods]Fresh soybean meal was divided into eight treatment groups,which was treated with 0,0.1,1 and 10 mmol·L^(-1)MDA,and also treated with 0,0.1,1 and 10 mmol·L^(-1)MDA and 0.6 mg·mL^(-1)TP,respectively,and the contents of carbonyl,sulfhydryl,and amino acid in soybean meal were determined.[Results]With the increasing concentration of MDA,the carbonyl content of soybean meal gradually increased(P<0.05),whereas the sulfhydryl and total sulfhydryl groups content,methionine,tyrosine,lysine contents,and in vitro digestibility of soybean meal protein decreased accordingly(P<0.05),the intrinsic fluorescence intensity of tryptophan increased first and then decreased,and its max peak was gradually blue-shifted,accompanied by an increase in the fluorescence intensity of Schiff base.In the oxidative group with the MDA concentration of 1 mmol·L^(-1),the carbonyl content in soybean meal significantly increased(P<0.05),the contents of sulfhydryl and total sulfhydryl groups significantly decreased(P<0.05),and the in vitro digestibility of soybean meal protein significantly decreased(P<0.01).In the high concentration MDA group(10 mmol·L^(-1)),the carbonyl content in soybean meal significantly increased(P<0.01),and the contents of sulfhydryl and total sulfhydryl,the in vitro digestibility of soybean meal protein significantly decreased(P<0.01).Meanwhile,the methionine,tyrosine,lysine content in soybean meal were remarkably lower than those of the control group(P<0.05).TP addition could mitigate the increase of carbonyl content,the decrease of sulfhydryl and total sulfhydryl groups,the decrease of methionine content,the decrease of in vitro digestibility of soybean meal protein,the decrease of intrinsic fluorescence intensity of tryptophan and the increase of Schiff base content in soybean meal.[Conclusions]1 mmol·L^(-1)MDA can trigger protein oxidation in s
作者
宋娟娟
谢婷
刘文涵
汪鹏
王岩
陈跃平
周岩民
SONG Juanjuan;XIE Ting;LIU Wenhan;WANG Peng;WANG Yan;CHEN Yueping;ZHOU Yanmin(College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,China)
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2023年第2期324-332,共9页
Journal of Nanjing Agricultural University
基金
江苏现代农业产业技术体系建设专项资金(JATS2021466)。
关键词
豆粕
蛋白质氧化
丙二醛
茶多酚
体外消化率
soybean meal
protein oxidation
malonaldehyde
tea polyphenols
in vitro digestibility
