Dodecanol

Abstract: The ideal method to produce a terminal metabolite inhibitor of cell growth and production is to remove and recover it from the fermenting broth as it formed. Extractive fermentation is achieved in the case of ethanol production by coupling both fermentation and liquid-liquid extraction, The solvent of extraction is 1-dodecanol (or a mixture 1-dedecanol, 1-tetradecanol); study of the inhibitory effect of primary aliphatic alcohols of different chain lengths shows that no growth is observed in the presence of alcohols which have between 2 and 12 carbons. This effect is suppressed when the carbon number is 12 or higher. A new reactor has been used-1 pulsed packed column. Pulsation is performed pneumatically. Porous material used as a package adsorbs the cells. The fermentation broth is pulsed in order to (1) increase the interfacial area between the aqueous phase and the dodecanol, (2) decrease gas holdup. Alcoholic fermentation, performed at 35 degrees C on glucose syrup, permits the total utilization of glucose solution of 409 g/L with a yeast which cannot-in classical process- completely use solutions with 200 g/L of glucose. The feasibility of a new method of fermentation coupling both liquid-liquid extraction and fermentation is demonstrated. Extension of this method is possible to any microbial production inhibited by its metabolite excretion.

Abstract: Porcine pancreatic lipase immobilized on celite particles has been employed as a catalyst for the esterification of dodecanol and decanoic acid in a predominantly organic system. Solvent influence on the equilibrium position and on the catalyst activity has been studied using 20 solvents, including aliphatic and aromatic hydrocarbons, ethers, ketones, nitro- and halogenated hydrocarbons, and esters. The equilibrium constant for esterification correlates well with the solubility of water in the organic solvent, which in turn shows a good relationship with a function of Guttman's donor number and the electron pair acceptance index number of the solvent. This may be rationalized in terms of the requirements for solvation of water and of the reactants. The catalyst activity, measured as the initial rate of the esterification reaction, is best correlated as a function of both n-octanol-water partition coefficient (log P) and either the electron pair acceptance index or the polarizability.

Abstract: The effects of normal alcohols up to 1-dodecanol on phase transitions in phosphatidylcholines and phosphatidylethanolamines have been studied using chlorophyll a as fluorescent probe. With the phosphatidylcholines, alcohols up to octanol cause a lowering of the transition temperature, and a broadening of the transition, whereas for dipalmitoylphosphatidylethanolamine, only a lowering of the transition is observed. The lowering of the phase transition temperature in dipalmitoylphosphatidylcholine by butanol and hexanol is close to that expected for ideal behavior, but the behavior of the longer chain alcohols becomes less ideal. The effects of these alcohols on mixtures of lipids have been studied, and they illustrate the care necessary if these plots of temperatures of onset and completion of gel phase formation are to be called "phase diagrams". The effect of 1 -octanol on mixtures of lipids is to increase the proportion of lipid present in the lipid-crystalline state. In contrast, 1-decanol causes an increase in the phase transition temperature for dimyristoylphosphatidylcholine, although it lowers the transition temperature for dipalmitoylphosphatidylcholine, and 1 -dodecanol raises the transition temperature for both of these phosphatidylcholines, although it lowers that for dipalmitoylphosphatidylethanolamine. Dodecanol appears to behave in these lipid bilayer membranes as a lipid with a phase transition temperature of ca. 55 degrees C. Anesthesia is discussed as a phenomenon of liquidus extension: alcohols up to 1 -octanol increase the proportion of lipid in the liquidus state and result in anesthesia, whereas the longer alcohols do not, and result in catalepsy.