英文摘要 |
The topic of this project is to develop the production technology of lactic acid bacteria fermented shellfish extracts. The fermented freshwater clam and oyster extracts are the aim of this year. The conditions of lactic acid fermentation will be established, and the biological activities of fermented shellfish products such as antioxidation, ACE inhibition, and antimutagenicity will be evaluated. The collected data could be used for the future lactic acid fermented shellfish health food development. The production technology of shellfish extracts was whole freshwater clam: water = 1: 2 (w/v) and oyster: water = 1: 4 (w/v) at 100 ℃ for 40 min. Freshwater clam extracts added 0.5% sucrose and oyster extracts were fermented with 2% Lactobacillus plantarum BCRC 10069 and 2% Lb. plantarum BCRC 12250 at 37 ℃ for 4 hr. In the evaluation on the antioxidation effect of the fermented shellfish extracts, the ability for scavenging DPPH free radical of the fermented freshwater clam extracts was examined to perform 30.76-34.18%. Scavenging DPPH free radicals of the fermented oyster extracts demonstrated 41.07% antioxidative activity. The ability of chelating Fe+ of the fermented freshwater clam and the fermented oyster extracts exhibited 142.81-179.80% and 171.69%, respectively. The inhibitory activity against ACE of the fermented freshwater clam extracts and oyster extracts were 58.13% and 35.03%. Only the fermented freshwater extracts performed inhibition of mutagenicity induced by indirect-acting mutagen B[a]P evaluated by Sal. typhimurium TA 98,measured as 76.54%. The oligosaccharides of the fermented freshwater clam extracts and oyster extracts were analyzed by TLC. The results showed no spots on the fermented freshwater clam extracts and only one spot on the fermented oyster extracts. As a results, 0.5% sucrose was added for freshwater clam extracts fermentation. However, additional carbon source was not necessary for oyster extracts fermentation. SDS-PAGE profile of lactic acid bacteria fermented freshwater clam extracts and oyster extracts suggested that most protein were rapidly degraded after 4 hr fermentation. In addition, the pH of fermented freshwater clam extracts and oyster extracts decreased from 4.41 to 3.74 and from 4.35 to 4.16; titratable acidity was increased from 0.14% to 0.27% and from 0.14% to 0.16%, LAB counts maintained 8.77-8.27 log CFU/mL and 8.67-7.68 log CFU/mL storage at 4 ℃ for 14 days. At 25 ℃ for 3 days, the two fermented shellfish extracts exhibited pH value was decreased from 4.41 to 3.29 and from 4.35 to 4.07; titratable acidity was increased from 0.14% to 0.59% and from 0.14% to 0.18%, LAB counts maintained 8.77-8.78 log CFU/mL and 8.67-8.29 log CFU/mL. |