英文文摘
Chapter1 Review of literature and objectives
1.1Importance of Yeasts
1.2Growth and maintenance of yeast cultures
1.3Yeast Pathogenecity
2.Current classification of the yeasts
2.1Ribosomal RNA/DNA sequence comparisons for assessing phylogenetic relationships
2.2Phylogenetics
3.Importance of Phytate and phytase
3.1Microbial phytases
3.2Phytase producing yeasts
Chapter2 Screening of marine yeast strains from different habitats of China Seaand Indian Ocean
2.1Introduction
2.2Materials and methods
2.2.1Sample collection and culture media
2.2.2Phylogenetical analysis
2.3Results and discussion
3.1Introduction
3.2Materials and methods
3.2.1Screening of yeasts for phytase activity
3.2.2Phytase assay
3.3Results and discussion
Chapter4 Identification and classification of Phytase secreting yeast strains
4.1Introduction
4.2Materials and methods
4.2.1The yeast strains
4.2.2The morphology of cells
4.2.3Fermentation of sugars
4.2.4Assimilation of carbon compounds
4.2.5Assimilation of Nitrogen compounds
4.2.6Acid production from glucose
4.2.7Hydrolysis of urea
4.2.8Gelatin liquifaction
4.2.918S rRNA gene sequencing and phylogenetic analysis
4.3Results and discussion
4.3.1Morphology of colonies and cells
4.3.2Biochemical and physiological characteristics of ten yeast strains
4.3.3Growth on Nitrogen sources,different temperatures and other characteristics
4.3.4PCR results and genetic diversity
5.1Introduction
5.2Materials and methods
5.2.1Strains
5.2.2Medium and culture condition
5.2.3Purification of enzyme
5.2.4Determination of enzyme activity and total protein
5.2.5Gel electrophoresis
5.2.6Effects of pH and temperature on activity
5.2.7Effect of different salts on phytase activity
5.2.8Determination of Kinetic parameters
5.3Results and discussion
5.3.1Medium and culture condition
5.3.2Purification results and kinetic parameters
Overall conclusion and future prospects
References
List of publications
Acknowledgement