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吳郭魚加工剩餘物以 0.1、0.5、1.0 和 2.0 % 的蛋白酶水解，結果顯示，蛋白酶 濃度和水解速率呈正相關，且以蛋白酶 A 的水解率最佳。以蛋白酶 A 水解吳郭魚 加工剩餘物，水解 24 小時的水解率達平穩，且添加 0.5 和 2.0 % 無顯著差異。 本水解方法的水解率 33.69 %，乾物萃取率 76.92 %，粗蛋白萃取率 83.16 %。 以水解魚蛋白取代酵母萃取物，培養 EL、ST 和 PPP 3 株光合菌，結果顯示水解魚 蛋白對 3 株光合菌有良好的培養效果，培養 2 - 4 天即可達到生長平穩期，且吸 光值 (660 nm) 達到 2.0 以上，符合現場應用所需的濃度。 EL、ST 和 PPP 3 株自養殖池分離的菌株，型態和生化特性皆為桿狀、革蘭氏陰性 菌、具鞭毛移動性，但只有 PPP 能在黑暗有氧環境生長，且僅有 ST 不具過氧化氫 酶。聚合酶連鎖反應分析結果顯示，3 株光合菌均有光合成中心基因 pufM，確認 3 株光合菌均為紫色光合菌。全波長掃描結果顯示，三株光合菌在 805 和 865 nm 菌 有特徵峰，顯示具有細菌葉綠素 a。總類胡蘿素含量從高到低分別為 EL、ST 和 PPP，且彼此間均有顯著差異。16S rRNA 比對結果，EL 和 ST 與沼澤紅假單孢菌 ( Rhodopseudomonas palustris) 有最高的相似性，PPP 則與生芽紅細菌 ( Rhodobacter blasticus) 最相似。根據生化特性和序列比對結果，EL 和 ST 鑑定 為沼澤紅假單孢菌，PPP 鑑定為生芽紅細菌，且因為 EL 和 ST 在菌落外觀、過氧 化氫酶、碳源利用及總類胡蘿素含量上有差異，因此歸為不同菌株。 不同濃度的 EL、ST 和 PPP 培養輪蟲，以 108 CFU/ml 菌濃度最適合培養輪蟲，且 EL 的培養效果最佳，輪蟲起始密度 50 inds./ml，接種後第 5 天，輪蟲密度可達 到 352 inds./ml。

Hydrolysis tilapia by-product with 0.1, 0.5, 1.0 and 2.0 % of proteases. The results showed that there was positive correlation between protease concentration and hydrolysis rate, and the protease A group had highest degree of hydrolysis (DH). Hydrolysis tilapia by-product with protease A, the DH leveled off after 24 hours of hydrolysis. In addition, there was no significant difference in DH between 0.5 and 2.0 % of protease A. This hydrolysis method had 33.69 % of DH, 76.92 % of dry matter extraction and 83.16 % of crude protein extraction. EL, ST and PPP 3 strains of photosynthetic bacteria were cultured with fish protein hydrolysate (FPH) instead yeast extract. The results indicated that FPH was favorable for photosynthetic bacteria as a component of medium. The photosynthetic bacteria reached stationary phase within 2 - 4 days, and the optical density were above 2.0, which can be applied on practical aquaculture. EL, ST and PPP 3 strains of photosynthetic bacteria were isolated from - 1 - 1082442 1. 2. 3. 1. 2. aquaculture ponds. The morphological and biochemical characteristic of these strains were rod shape, gram negative and had flagellar motility. Only PPP had ability of aerobic growth in dark, and only ST did not have catalase. According to the result of polymerase chain reaction, all 3 strains had pufM photosynthetic reaction center gene, which confirm that they were classified to purple phototrophic bacteria. The results of full wavelength showed characteristic absorption peaks at 805 and 865 nm for bacteriochlorophyll a in all 3 strains. Total carotenoid contents were EL, ST and PPP from high to low, and there was significant difference between each strain. 16S rRNA sequencing indicated EL and ST had highest similarity to Rhodopseudomonas palustris; PPP had highest similarity to Rhodobacter blasticus. Based on the results of biochemical characteristic and 16S rRNA sequencing, EL and ST were identified as Rhodopseudomonas palustris; PPP was identified as Rhodobacter blasticus. Moreover, we conclude that EL and ST were different strains because they have different characters on colony morphology, catalase, carbon source utilities and total carotenoid contents. Using different concentrations of EL, ST and PPP strains to culture rotifer, the optimal concentration was 108 CFU/ml. The EL strain had highest efficiency to rotifer culture. Fed rotifer with 108 CFU/ml of EL, the density increased to 352 individuals/ml at 5th day from initial density of 50 inds./ml.