Title Page
Contents
ABSTRACT 13
I. INTRODUCTION 16
II. LITERATURE REVIEW 18
1. Single-cell protein 18
1.1. Definition and characteristics of single-cell protein 18
1.2. Classification by single-cell protein source 19
1.3. Technology for single-cell protein production 28
1.4. Market trend of single-cell protein 30
2. Saccharomyces cerevisiae 31
2.1. General characteristics 31
2.2. Characteristics of the single-cell protein source 32
III. MATERIALS AND METHODS 33
1. Isolation of yeast 33
1.1. Isolation of yeast in food 33
1.2. Yeast identification by 25-58s rRNA analysis 35
2. Screening of yeast for production of single-cell protein 36
2.1. Analysis of hemolysis 36
2.2. Analysis of cell viability 36
2.3. β-glucosidase and β-glucuronidase activities 38
3. Development of fermentation conditions 39
3.1. Development of media 39
3.2. Establishment of conditions 41
3.3. Compare to commercial media of biomass production rates 43
4. Analysis of the characteristics and functions of single-cell protein 44
4.1. Analysis of crude protein 44
4.2. Protein decomposition rate 45
4.3. DPPH radical scavenging activity 47
4.4. Inhibitory activity against lipase 48
5. Statistical analysis 50
IV. RESULTS AND DISCUSSION 51
1. Isolation of yeast for single-cell protein production 51
2. Selection of yeast for single-cell protein production 55
2.1. Hemolytic property 55
2.2. Cytotoxicity of yeast isolates 58
2.3. Determination of β-glucosidase and β-glucuronidase activities 61
3. Development of optimal fermentation conditions for single-cell protein production 62
3.1. Development of optimal fermentation medium 62
3.2. Establishment of optimal fermented conditions 69
3.3. Verification of optimal fermentation conditions 77
4. The characteristics and functions of single-cell protein 81
4.1. Assessment of crude protein content in single-cell protein 82
4.2. Protein decomposition rate of single-cell protein 84
4.3. Antioxidant activity of single-cell protein 86
4.4. Inhibitory activity of single-cell protein against lipase 88
V. SUMMARY AND CONCLUSION 90
VI. REFERENCE 94
ABSTRACT IN KOREAN 111
Table 1. Compositions of microorganisms 19
Table 2. The protein content of bacteria as single-cell protein on... 21
Table 3. The protein content of algae as single-cell protein on... 23
Table 4. The protein content of fungi as single-cell protein on... 25
Table 5. The protein content of yeast as single-cell protein on... 27
Table 6. Combinations for fermentation media 40
Table 7. Twelve types of fermentation conditions 42
Table 8. Composition of decomposition reaction solution 46
Table 9. Identification of 34 isolates from fermented foods 52
Table 10. Isolation of yeasts for single-cell protein 53
Table 11. Hemolytic property of the yeast isolates 56
Table 12. Classification of cytotoxicity according to cell viability 59
Table 13. Development of optimal fermentation medium 68
Table 14. Optimizing fermentation conditions 76
Table 15. Manufacturing cost of 1L volume medium for production... 80
Table 16. Comparison of crude protein content from protein sources 83
Figure 1. Steps for single-cell protein production. 29
Figure 2. Flowchart for the production of single-cell protein 34
Figure 3. Cell viability of RAW 264.7 cells influenced by yeast isolates. 60
Figure 4. Saccharomyces cerevisiae SMFM2021-MAK1 biomass... 63
Figure 5. Saccharomyces cerevisiae SMFM2021-MAK2 biomass... 64
Figure 6. Saccharomyces cerevisiae SMFM2021-MAK3 biomass... 65
Figure 7. Saccharomyces cerevisiae SMFM2021-MAK4 biomass... 66
Figure 8. Z. rouxii biomass weight when fermented in 12 types of media 67
Figure 9. Comparison of Saccharomyces cerevisiae... 71
Figure 10. Comparison of Saccharomyces cerevisiae... 72
Figure 11. Comparison of Saccharomyces cerevisiae... 73
Figure 12. Comparison of Saccharomyces cerevisiae... 74
Figure 13. Comparison of biomass weight of each isolate according... 75
Figure 14. Biomass weight of Saccharomyces cerevisiae... 78
Figure 15. Biomass weight of Saccharomyces cerevisiae... 79
Figure 16. Isolates selection flowchart for single-cell protein... 81
Figure 17. The single-cell protein of Saccharomyces cerevisiae... 82
Figure 18. In vitro protein decomposition rate. 85
Figure 19. Antioxidant activity of single-cell protein. 87
Figure 20. Inhibitory activity of single-cell protein against lipase. 89