Syldatk C, Lang S, Matulovic U, Wagner F
Z Naturforsch C Biosci. 1985 Jan-Feb;40(1-2):61-7. doi: 10.1515/znc-1985-1-213.
In a simple phosphate buffer or a sodium chloride solution resting cells of Pseudomonas spec. DSM 2874 produced up to 15 g/l of different rhamnolipids. The rhamnolipid composition of the organic crude extract depended on the temperature during the cultivation and on the C-source. The optimal sodium chloride concentration for rhamnolipid formation was about 100 mM/l and the optimal phosphate buffer concentration about 65 mM/l. The optimal pH-value for the production of rhamnolipids from n-alkanes or glycerol was in the range pH 6.0-7.2. While rhamnolipid formation with glycerol as the sole C-source showed a wide optimum ranging from 27 degrees up to 37 degrees C, production of rhamnolipids from n-alkanes had a sharp optimum at 37 degrees C. The addition of multivalent cations, different N-sources and EDTA caused an inhibition of rhamnolipid formation, while the n-alkane concentration had no influence. Specific rhamnolipid formation decreased with increasing cell concentration. Various C-sources were suitable for the formation of rhamnolipids by resting cells of Pseudomonas spec. DSM 2874. Yields, which were comparable to those obtained on n-alkanes or glycerol, were found for stearic acid, fatty alcohols and vegetable oils. A study of the time course of glycolipid production of resting cells was carried out in a 20 1-bioreactor with an intensor system and with n-tetradecane as the sole C-source.
在简单的磷酸盐缓冲液或氯化钠溶液中，假单胞菌属DSM 2874的静止细胞可产生高达15 g/l的不同鼠李糖脂。有机粗提物中鼠李糖脂的组成取决于培养过程中的温度和碳源。鼠李糖脂形成的最佳氯化钠浓度约为100 mM/l，最佳磷酸盐缓冲液浓度约为65 mM/l。以正构烷烃或甘油生产鼠李糖脂的最佳pH值范围为6.0 - 7.2。以甘油作为唯一碳源时，鼠李糖脂的形成在27℃至37℃范围内有较宽的最佳温度范围，而以正构烷烃生产鼠李糖脂在37℃时有一个急剧的最佳温度。添加多价阳离子、不同的氮源和乙二胺四乙酸会抑制鼠李糖脂的形成，而正构烷烃浓度则没有影响。随着细胞浓度的增加，特定鼠李糖脂的形成会减少。各种碳源都适合假单胞菌属DSM 2874的静止细胞形成鼠李糖脂。对于硬脂酸、脂肪醇和植物油，其产量与以正构烷烃或甘油获得的产量相当。在一个配备强化系统且以正十四烷作为唯一碳源的20升生物反应器中，对静止细胞糖脂生产的时间进程进行了研究。
