chromatographic determination of glycoalkaloids in eggplant

TABLE OF CONTENTS
LIST OF FIGURES .......................................................................................................viii
LIST OF TABLES............................................................................................................ x
CHAPTER 1. INTRODUCTION ................................................................................... 1
1.1. Eggplant ............................................................................................... 1
1.2. Plant Secondary Metabolites ............................................................... 3
1.3. Steroidal Glycoalkaloids...................................................................... 5
1.3.1. Chemical Structure of Glycoalkaloids........................................... 7
1.3.2. Toxicity of Glycoalkaloids ............................................................ 9
1.3.3. Beneficial Effects of Glycoalkaloids ........................................... 12
1.3.4. Factors Influencing Glycoalkaloid Levels................................... 13
1.3.5. Methods of Analysis for Glycoalkaloids ..................................... 15
CHAPTER 2. HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC ............. 18
2.1. Introduction........................................................................................ 18
2.2. Experimental...................................................................................... 21
2.3. General HPLC Conditions................................................................. 22
2.4. Results and Discussion ...................................................................... 22
2.4.1. Effect of Buffer Type................................................................... 27
2.4.2. Effect of Temperature.................................................................. 29
2.4.3. Effect of Solvent Type................................................................. 31
2.4.4. Effect of pH ................................................................................. 33
2.4.5. Calibration Results....................................................................... 35
CHAPTER 3. GAS CHROMATOGRAPHY MASS SPECTROMETRY
(GC-MS) SOLID - PHASE MICROEXTRACTION (SPME) ............ 41
3.1. Introduction........................................................................................ 41
3.1.1. Derivatization for Gas Chromatography (GC) ............................ 45
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