| 摘要註: |
角黃素(Canthanxanthin),為類胡蘿蔔素的一種,具有抗氧化、提高免疫力、保護皮膚等功效,研究也指出角黃素對多種癌症具有預防和抑制的效果。近年來,產角黃素的菌株逐漸被篩選分離出來。透過誘變方式改良微生物菌種之性能,獲得高產量穩定的微生物菌種,以進行高密度生產來降低成本,具有很高的市場潛力及開發價值。 本研究所使用的菌株為紅色放線菌W38,經食品工業發展研究所鑑定為Dietzia sp.。W38菌株經先前研究發現能夠產生抗氧化色素,經鑑定後為角黃素,本研究利用NTG突變技術誘使W38菌種變異,並篩選出產量較高之菌株M1。但M1菌株高產量特性持續時間不長,因此我們探討M1菌株最佳的NTG濃度和反應時間;比較NTG誘變和UV誘變對於產量提升的效果,並檢測所獲得之變異株的產量穩定性和最佳生長時間。實驗結果顯示,M1菌株最佳的誘變條件是NTG濃度為2 mg/ml下反應40分鐘,可得到較高的正突變率及最佳的產量提升效果;最佳的UV誘變條件下,產量提升的效果不如NTG的效果好。以NTG繼續誘變M1菌株後找到的新變異株命名為M2,與原始菌株W38及變異株M1在相同的培養基條件及最佳培養時間下的生產能力,新變異株M2之產量(OD480)由W38的0.111提升至0.476,有顯著提升且經連續十代的培養後其OD480值仍高於0.45。於M2培養基中加入0.5、1、1.5 %之Casamino Acids皆不會提高角黃素的產量;pH 6.4對於M2菌株是最佳的培養條件。 Canthaxanthin is a carotenoid, it is a potent antioxidant, improving immunity and protect skin. It has been research to prevent Tumor in the medical. At present, Canthaxanthin is satisfied through chemical synthesis, but the chemical synthesis of Canthaxanthin requires a very high level of control and can produce compounds that have undesired side effects and may be allergens in certain consumers. Therefore, in view of the global economic value of Canthaxanthin and increasing awareness of consumers, the production of these materials from natural sources has become an area of intensive investigation. This red Actinomycetes W38 was identified to Dietzia sp. by Food Industry Research and Development Institute. In preliminary experiments, the main pigment of this strain was identified to be a canthaxanthin. This study improved the strain by 1-methyl 3-nitro 1-nitrosoguanidine (NTG) and UV to obtain a higher level of Canthaxanthin strain M1. But M1 strain can not keep the higher yield property. Therefore, this study was directed to determine the optimum conditions to obtain the highest level of Canthaxanthin and keep this property by Dietzia sp. M1 mutant. Results showed that the best condition was treated 40 min with 2 mg/mL 1-methyl 3-nitro 1-nitrosoguanidine (NTG) and better than the best condition of UV irradiation. The mutant strains M2 were obtained using 1-methyl 3-nitro 1-nitrosoguanidine (NTG) from mutant strains M1. The mutant strains M2 has higher OD480 (0.476) than strains W38 (0.111) and also can keep the higher yield property for ten times Subculture (about 0.45). Casamino Acids can not improved the strain M2, and pH 6.4 is the optimum conditions for strain M2. |