Antibacterial Activity and Mechanism of Tetrapleura Tetraptera Extract and its Application in Pork

论文摘要

T.tetraptera是一种可食用的土著水果香料,它在西非民间医学中被用来治疗各种各样的人类疾病。本研究旨在探讨四翅目根皮提取物对部分食源性致病菌的抗菌活性及作用机理。T.tetraptera的提取溶剂为无水乙醇,T.tetraptera根部提取物的最低抑菌浓度和最低杀菌浓度的范围分别是3.125–25μg/ml和6.25μg/mL–50μg/mL,T.tetraptera树皮提取物的最低抑菌浓度和最低杀菌浓度的范围分别是6.25–50μg/ml和12.5–50μg/ml。用牛津杯和白纸测试抑菌圈,发现最小抑菌量为20 mm,最大抑菌量为28 mm。通过对T.tetraptera细胞完整性和细胞膜通透性的形态学损伤以及细胞结构和生长模式的变化进行了时间杀伤实验,研究了T.tetraptera对细菌的抗菌机理,分析了细胞内的ATP、DNA、蛋白质及酶等物质,明确强调了T.tetraptera对大肠杆菌和金黄色葡萄球菌的破坏作用。这些细胞成分的释放表明T.tetraptera植物根提取物改变了病原菌的细胞膜,大大抑制了活菌的生长。细菌蛋白SDS-PAGE分析表明,可溶性蛋白明显减少,另外,呼吸代谢结果也表明,T.tetraptera根提取物对EMP途径中的大肠杆菌和金黄色葡萄球菌以及HMP途径中的关键酶均有抑制作用。这些提取物在猪肉中进行了7天的抑菌和杀菌试验。结果表明,T.tetraptera提取物对肉制品的质地和感官特性无不良影响,且保持了肉制品的品质和感官特性。另外,贮藏5天和7天的肉样之间也无显著性差异。本研究明确表明,T.tetraptera提取液是一种新型抗菌药物的潜在来源,已被证明对耐药病原菌有效。

论文目录

• DEDICATION
• ACKNOWLEDGEMENT
• ABSTRACT
• 摘要
• CHAPTER ONE INTRODUCTION
•   1.1 Background information
•   1.2 Infectious disease and multiple antibiotic resistances of bacteria
•   1.3 Food pathogens used in this research
•   1.4 Contamination of pathogens in food products
•     1.4.2 Meat contamination and related microorganisms and their method of control
•   1.5 Medicinal plants
•     1.5.1 Introduction
•     1.5.2 Antimicrobial activities of medicinal plant extracts
•     1.5.3 Application of T. tetraptera in food product
•       1.5.3.1 Introduction of T. tetraptera （prekese）
•       1.5.3.2 Application of antibacterial properties of T. tetraptera in food product
•       1.5.3.3 Application of antioxidant properties of T. tetraptera
•   1.6 Problem statement
•   1.7 Purpose of this research
•   1.8 Objective of the present study
• CHAPTER TWO ANTIBACTERIAL ACTIVITY OF T. TETRAPTERA AGAINST SOME SELECTEDFOODBORNE PATHOGENS
•   2.1 Introduction
•   2.2 Collection of the T. tetraptera material
•   2.3 Extraction of T. tetraptera plant material
•   2.4 Experimental materials and methods
•     2.4.1 Experimental reagents and materials
•     2.4.2 Main experimental instruments and equipment
•     2.4.3 Experimental strains and culture medium
•       2.4.3.1 Test bacterial strains
•       2.4.3.2 Medium used for strains
•   2.5 Composition analysis of T. tetraptera root extract
•   2.6 Evaluation of Antibacterial Activity of T. tetraptera
•     2.6.1 Determination of Minimum Inhibitory Concentration （MIC） and Minimum BactericidalConcentration （MBC）
•     2.6.2 Disc diffusion assay
•     2.6.3 Time-Kill analysis of the T. tetraptera extract
•   2.7 Data Processing and Analysis
•   2.8 Results and discussion
•     2.8.1 Analysis of the chemical compositions of T. tetraptera
•     2.8.2 Evaluation of Antibacterial Activity T. tetraptera extract
•       2.8.2.1 Determination of the MIC and the MBC
•       2.8.2.2 Disc diffusion assay
•       2.8.2.3 Time-Kill analysis of the T. tetraptera extracts
•   2.9 Summary of this chapter
• CHAPTER THREE ANTIBACTERIAL MECHANISM OF THE T. TETRAPTERA AGAINST E. COLI AND S. AUREUS
•   3.1 Introduction
•   3.2 Experimental materials and methods
•     3.2.1 Experimental reagent and materials
•     3.2.2 Main experimental instruments and equipment
•     3.2.3 Experimental strains and culture medium
•       3.2.3.1 Test bacterial strains
•       3.2.3.2 Medium used for strains: Same as 2.4.3.2
•   3.3 Examination of the cell membrane integrity
•   3.4 Release of cellular materials
•   3.5 Quantification of DNA in bacterial cells
•   3.6 Release of cellular proteins concentration
•   3.7 Determination of ATP Concentration
•   3.8 Nuclei acid staining
•   3.9 Protein fractions （SDS-PAGE）
•   3.10 Measurement of cellular adenosine triphosphatase （ATPase） and alkaline phosphatase（AKP） activity affected by T. tetraptera extract
•   3.11 Effects of the T. tetraptera extract on the respiratory metabolism
•   3.12 The activity of enzymes in the HMP and EMP pathways
•   3.13 Data Processing and Analysis
•   3.14 Results and discussion
•     3.14.1 TEM analysis
•     3.14.2 Release of Cellular Materials
•     3.14.3 Quantification of DNA
•     3.14.4 Release of cellular protein concentrations in bacterial cells
•     3.14.5 Evaluation of cellular ATP concentration
•     3.14.6 Nuclei acid staining
•     3.14.7 Proteins contents and SDS-PAGE fractionation
•     3.14.8 Measurement of the ATPase and AKP activity
•     3.14.9 Effect of T. tetraptera root extract on the respiratory metabolism
•     3.14.10 Effects of T. tetraptera root extract on enzyme activities in HMP shunt and the EMPpathway
•   3.15 Summary of this chapter
• CHAPTER FOUR ANTIBACTERIAL ACTIVITY OF THE T. TETRAPTERA AGAINST SOME SELECTEDFOODBORNE PATHOGENIC BACTERIA IN PORK
•   4.1 Introduction
•   4.2 Experimental materials and methods
•     4.2.1 Experimental reagents and materials: Same as 2.4.1
•     4.2.2 Main experimental instruments and equipment
•   4.3 Experimental strains and culture medium
•     4.3.1 Test bacterial strains: Same as 3.2.3.1
•     4.3.2 Medium used for strains
•   4.4 Antimicrobial activity testing in pork
•   4.5 Chroma and texture analysis of meat products
•     4.5.1 Texture analysis of meat products
•   4.6 Sensory evaluation
•   4.7 Data Processing and Analysis
•   4.8 Results and discussion
•     4.8.1 Antimicrobial activity testing in pork
•     4.8.2 Chroma and texture analysis of meat products
•       4.8.2.1 Chroma and texture analysis of pork
•       4.8.2.2 Chroma and texture analysis of beef
•     4.8.3 Sensory evaluation of meat products
•       4.8.3.1 Sensory evaluation of pork
•       4.8.3.2 Sensory evaluation of beef
•   4.9 Summary of this chapter
• CHAPTER FIVE General conclusion and recommendation
•   5.1 Conclusion
•   5.2 Recommendation
• REFERENCES
• APPENDIX

文章来源

类型: 硕士论文

作者: KWABENA AGYEMANG

导师: 林琳,HAIYING CUI

关键词: 抗菌活性,抗菌机理,结构和感官特征

来源: 江苏大学

年度: 2019

分类: 基础科学,工程科技Ⅰ辑

专业: 生物学,轻工业手工业

单位: 江苏大学

分类号: TS201.3

DOI: 10.27170/d.cnki.gjsuu.2019.000111

总页数: 122

文件大小: 15486K

下载量: 14