Development of functional fish feed additive of fermented soy product using mixed strains
| Autor: | Chung, Yun-Fong, 鍾昀峰 |
|---|---|
| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 104 The demand for the protein of animal origin continuously increases in the world due to the booming development of the aquaculture. The shortage of fish meal prompted the development of alternative plant based feed. Soybean is rich in protein and supply sufficient. However, the anti-nutrients in soybean, especially phytate, can cause adverse effects on fish growth. In this study, after screening phytate degredation activity among 12 lactic acid bacteria (LAB) stains with anti-inflammatory activity, GABA production, or antibacterial activity isolated from fish intestine, and the strains of FPP 2509, FPS 2520 and FPA 3709 were chosen for their over 65% phytate degradation activity in soybean homogenate. The strain of Bacillus subtilis natto N1 isolated from commercial natto was demonstrated to have strong protein digestion activity in soybean homogenate that the free amino nitrogen (FAN) content was increased from 263.42 ± 18.16 mg/100 mL to 334.87 ± 53.43 mg/100 mL after fermentation by this strain at 37oC for 48 hr. The mixed cultures by combination of natto N1 strain with the 3 chosen LAB strains were further evaluated for the protein and phytate degradation efficacy in soybean homogenate to prepare a fish feed additive with high soluble nitrogen content and low content of anti-nutrient factors. The best combination of natto N1 with FPA 3709 was chosen due to both the highest FAN content and phytate degradation in soybean homogenate. The optimum conditions for preparation of fish feed additive with the FAN content of 351.23 ± 44.10 mg/100 mL and 71.93% phytate degradation by fermenting soybean homogenate with these 2 strains were to inoculate FPA 3709 and natto N1 strains at 4 log CFU/mL with a cell ratio of 1:2 cell and incubated at 30oC for 72 hours. Also, the peptide content, a part of fish essential amino acid and aglycone form isoflavones increasing after mixed cultures fermentation. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|