利用耐鹽菌自醬油粕生產保濕因子四氫嘧啶之研究

Abstract

本研究將以先前分離自台南沿海地區之北門單胞鹽菌（Halomonas beimenensis sp. nov.）新物種作為嗜鹽微生物發酵並生產純化ecotine之研究。Halomonas beimenensis為一種耐鹽菌，其可以在體內產生相容性溶質(compatible solute)調整滲透壓，因此可於高鹽的環境中生存，此相容性溶質為一種稱為ectoine的化合物，此種化合物具有水和特性，目前被認為具有開發為保養品的潛力。本研究期望利用發酵培養技術並建立穩定之生產模式，研發出有效、低成本的含鹽廢棄物轉換生產美粧原料技術，並可解決含鹽副產物造成的問題，有助於廢棄物資源利用與創新。 本研究探討Halomonas beimenensis在不同培養狀態及培養方法對生成ectoine產量之優化生產條件探討。在標準培養基並利用two-step fed-batch方法於37℃下培養，ectoine的最大產量可達3.52g/L。在萃取後給予菌體新鮮培養基，可於48小時內重新合成ectoine。Halomonas beimenensis可以利用bacterial milking法培養，使菌體重複累積ectoine含量，循環培養次數可達10次。 利用豆粕取代標準培養基的探討，將水與豆粕以1:2的比例混合，菌體在接種後的36小時進入平穩期。利用豆粕液完全取代標準培養基，並用two-step fed-batch法生產ectoine，最大產量為1.42 g/L。同時利用標準培養基及豆粕液，two-step fed-batch中第一階段依然使用標準培養基進行，而第二階段則改用高鹽度的豆粕液，最大產量達2.22 g/L。 由本實驗結果證實，此優化條件所使用的醬油粕可以降低生產成本並具有商業化生產應用之價值。同時，ectoine是天然的細胞保護劑，同時具有多項功能，未來相當具有開發多功能化粧品之潛力。

In this study, Halomonas beimenensis, a novel halophilic microorganism isolated from the abandoned Beimen saltern in southern Taiwan, was used to produce and purify ectoine via fermentation. Halomonas beimenensis is a salt-tolerant bacterium that can produce a compatible solute in the body, which allows it to adjust its osmotic pressure and survive in a high-salt environment. This compatible solute is a compound called ectoine. As this compound has hydration properties, it is now considered to have potential for the development of skin care products. This study will improve a combined fermented process to establish a stable production model and develop effective, low-cost key value-added technologies to convert salt-containing waste for beauty materials, and solve the problem caused by salt-laden waste. This study investigated the optimal production conditions for the production of ectoine by Halomonas beimenensis. The ectoine yield reached 3.52 g/L in standard culture conditions using the two-step fed-batch method. At the same time, bacterial milking method was adopted to re-incubate Halomonas beimenensis to increase the accumulation of ectoine, the bacteria can be recirculated ten times. The ecotine yield was 1.42 g/L in trials using soy sauce residue instead of standard medium, where water and soy sauce residue were mixed at a 1:2 ratio. In the two-step fed-batch method, the first stage was carried out using standard medium, and the second stage was carried out using soy meal culture, resulting in an ectoine yield of 2.22 g/L. This optimized condition could reduce the cost of production and improve the commercial production value. Ectoine is a natural cytoprotective agent, and has several functions and a promising potential for the development of multi-functional cosmetic products.