| 摘要 | 第6-7页 |
| ABSTRACT | 第7页 |
| Abbreviation | 第15-16页 |
| CHAPTER 1 Background and objectives | 第16-25页 |
| 1.1 General introduction | 第16-17页 |
| 1.2 Milk Proteins | 第17-20页 |
| 1.2.1 Overview of bioactive peptides | 第18页 |
| 1.2.2 Milk-derived bioactive peptides | 第18页 |
| 1.2.3 Enzymatic hydrolysis by digestive enzymes | 第18-19页 |
| 1.2.4 Microbial fermentation | 第19-20页 |
| 1.3 Bioactivities from peptides and health significance | 第20-23页 |
| 1.3.1 Antidiabetic functionalities of milk protein-derived bioactive peptides | 第21页 |
| 1.3.2 Effect of milk protein on insulin secretion | 第21页 |
| 1.3.3 Antidiabetic applications of bioactive peptides | 第21页 |
| 1.3.4 In vitro antidiabetic effect of peptides | 第21-23页 |
| 1.4 Objectives of the study | 第23-25页 |
| 1.4.1 The Specific Objectives of this Research are: | 第23-25页 |
| CHAPTER 2 Effects of microwave and ultrasound pretreatments on preparation of Glycomacropeptide withtrypsin as a source DPP-IV inhibitory peptide | 第25-36页 |
| 2.1 Introduction | 第25-26页 |
| 2.2 Materials and methods | 第26-30页 |
| 2.2.1 Materials and reagents | 第26页 |
| 2.2.2 Instruments equipments | 第26页 |
| 2.2.3 Determination of protein content | 第26页 |
| 2.2.4 Protease activity assay | 第26页 |
| 2.2.5 Trichloroacetic acid precipitation -Determination of short peptide content by forinolmethod | 第26-28页 |
| 2.2.6 Determination of the degree of hydrolysis of enzymatically digested samples by the o-Phthalaldehyde method (OPA method) | 第28页 |
| 2.2.7 Microwave and ultrasonic pretreatments | 第28页 |
| 2.2.8 Enzyme hydrolysis and degree of hydrolysis | 第28-29页 |
| 2.2.9 Assay of the DPP-IV-Inhibitory Activity | 第29页 |
| 2.2.10 Sttistical analysis | 第29-30页 |
| 2.3 Results and discussions | 第30-34页 |
| 2.3.1 Protein content and enzyme activity | 第30页 |
| 2.3.2 Effects of Microwaves and Ultrasound on degree of hydrolysis | 第30-32页 |
| 2.3.3 Effect on Enzymatic hydrolysis of GMP with different temperature, time, proteinconcentration and enzyme concentration | 第32页 |
| 2.3.4 Effects of substrate concentration on DPP-V inhibitory activity | 第32-33页 |
| 2.3.5 Effects of enzyme concentration, hydrolysis temperature and hydrolysis time on DPP-4inhibitory activity | 第33-34页 |
| 2.4 Conclusion | 第34-36页 |
| CHAPTER 3 Response surface optimization of dipeptidyal peptidase (DPP-IV) Inhibition ofglycomacropeptides hydrolysates | 第36-45页 |
| 3.1 Introduction | 第36-37页 |
| 3.2 Materials and methods | 第37-41页 |
| 3.2.1 Materials | 第37页 |
| 3.2.2 Experimental design of glycomacropeptide Concentrate Hydrolysate by CentralComposite (CCD) | 第37页 |
| 3.2.3 RSM and Generation of the Optimum GMP Hydrolysate. | 第37-40页 |
| 3.2.4 Enzyme hydrolysis and degree of hydrolysis | 第40页 |
| 3.2.5 Determination of DPP-IV Inhibitory Activity | 第40-41页 |
| 3.2.6 Statistical Analysis | 第41页 |
| 3.3 Results and discussion | 第41-44页 |
| 3.3.1 Hydrolysates Generated Within the Experimental Design | 第41-42页 |
| 3.3.2 The Effects of different Factors affecting on the DPP-IV Inhibitory Activity of TheHydrolysate | 第42-43页 |
| 3.3.3 Optimization and validation | 第43-44页 |
| 3.4 Conclusion | 第44-45页 |
| CHAPTER 4 Dipeptidyl peptidase-IV inhibitory peptides generated from Papain-Treated hydrolysis of aglycomacropeptide (cGMP20) protein | 第45-56页 |
| 4.1 Introduction | 第45-46页 |
| 4.2 Materials and methods | 第46-48页 |
| 4.2.1 Materials | 第46页 |
| 4.2.2 Preparation of the glycomacropeptide (GMP) hydrolysate | 第46页 |
| 4.2.3 Separation and Purification of DPP-IV Inhibitory Peptides | 第46-47页 |
| 4.2.4 Identification of DPP-IV Inhibitory Peptides by RP-HPLC-ESI-MS/MS | 第47页 |
| 4.2.5 Assay of the DPP-IV-Inhibitory Activity | 第47-48页 |
| 4.2.6 Peptide Synthesis | 第48页 |
| 4.2.7 Peptide-cutter tool predicts enzymatic cleavage sequence | 第48页 |
| 4.3 Results and discussion | 第48-54页 |
| 4.3.1 DPP-4 inhibitory activity of GMP with different molecular weight ranges | 第48-49页 |
| 4.3.2 Identification of peptide sequences | 第49-50页 |
| 4.3.3 DPP-IV inhibitory activity of synthetic peptides | 第50-53页 |
| 4.3.4 Peptide-cutter tool predicts enzymatic cleavage sequence | 第53-54页 |
| 4.4 Conclusion | 第54-56页 |
| CHAPTER 5 Effect of Glycomecropeptide (cGMP20) peptides on DPP-IV and GLP-1 in H716 cells | 第56-72页 |
| 5.1 Introduction | 第56-57页 |
| 5.2 Materials and methods | 第57-60页 |
| 5.2.1 Materials and reagents | 第57页 |
| 5.2.2 Instruments and equipments | 第57页 |
| 5.2.3 Test design | 第57页 |
| 5.2.4 cell culture | 第57-58页 |
| 5.2.5 Deermination the number of cells | 第58页 |
| 5.2.6 Cytotoxicity experiment | 第58页 |
| 5.2.7 Treatment of different concentrations of glycomacropeptide peptides NCI-H716 cells | 第58-59页 |
| 5.2.8 Extraction of DPP-4 and GLP-1 in cells | 第59页 |
| 5.2.9 Determination of intracellular DPP-4 activity | 第59页 |
| 5.2.10 Determination of GLP-1 secretion | 第59-60页 |
| 5.2.11 Statistical analysis | 第60页 |
| 5.3 Results and discussion | 第60-70页 |
| 5.3.1 DPP-4 half inhibition rate of linagliptin and active peptide | 第60-61页 |
| 5.3.2 Cell proliferation assay to determine optimal culture concentration | 第61页 |
| 5.3.3 Cytotoxicity test to determine the optimum culture concentration of the sample to betested | 第61-63页 |
| 5.3.4 Effect of sample to be tested on intracellular DPP-IV secretion | 第63-65页 |
| 5.3.5 Effect of sample to be tested on intracellular GLP-1 secretion | 第65-70页 |
| 5.4 Conculusion | 第70-72页 |
| CHAPTER 6 Overall conclusions | 第72-74页 |
| 6.1 Innovation points | 第73页 |
| 6.2 Outlook | 第73-74页 |
| References | 第74-80页 |
| 致谢 (Acknowledgement) | 第80-81页 |
| 作者简历 (Resume) | 第81-82页 |
