Hydrazines and their derivatives are versatile artificial and natural compounds that are metabolized by elusive biological systems. Here we identified microorganisms that assimilate hydrazones and isolated the yeast, Candida palmioleophila MK883. When cultured with adipic acid bis(ethylidene hydrazide) as the sole source of carbon, C. palmioleophila MK883 degraded hydrazones and accumulated adipic acid dihydrazide. Cytosolic NAD ؉ -or NADP ؉ -dependent hydrazone dehydrogenase (Hdh) activity was detectable under these conditions. The production of Hdh was inducible by adipic acid bis(ethylidene hydrazide) and the hydrazone, varelic acid ethylidene hydrazide, under the control of carbon catabolite repression. Purified Hdh oxidized and hydrated the C‫؍‬N double bond of acetaldehyde hydrazones by reducing NAD ؉ or NADP ؉ to produce relevant hydrazides and acetate, the latter of which the yeast assimilated. The deduced amino acid sequence revealed that Hdh belongs to the aldehyde dehydrogenase (Aldh) superfamily. Kinetic and mutagenesis studies showed that Hdh formed a ternary complex with the substrates and that conserved Cys is essential for the activity. The mechanism of Hdh is similar to that of Aldh, except that it catalyzed oxidative hydrolysis of hydrazones that requires adding a water molecule to the reaction catalyzed by conventional Aldh. Surprisingly, both Hdh and Aldh from baker's yeast (Ald4p) catalyzed the Hdh reaction as well as aldehyde oxidation. Our findings are unique in that we discovered a biological mechanism for hydrazone utilization and a novel function of proteins in the Aldh family that act on C‫؍‬N compounds.

A heterogeneous catalyst, FeOx/SiO2, prepared by the pore‐filling method, was found to be active in the transesterification of crude Jatropha oil with methanol. When the transesterification reaction was carried out with a reaction temperature of 220 °C, a catalyst amount of 15 wt%, a methanol/oil molar ratio of 218:1, and a reaction time of 3 h, the yield of fatty acid methyl esters (FAME) in the product exceeded 99.0 %, and met with EN standards for allowable contents of glycerine and mono‐, di‐, and tri‐glycerides. The correlation between the FAME production activity and measured acidity of the FeOx/SiO2 catalysts showed that the transesterification reaction was promoted via the acidic function of these catalysts, which are less inhibited by coexisting free fatty acids in the feedstock triglycerides.

A pair of diastereomers, I and II, of the titled complex were separated by liquid chromatography, and each of them crystallized in two different colors, green and orange. I(green) and II(green) were assigned to a mononuclear square pyramidal structure, while I(orange) and II(orange) to a polynuclear linear chain structure. The orange complexes turned green by heating at 195 °C in a few minutes. All of the four complexes undergo isomerization at 195 °C in the solid state to give an equilibrium mixture, I : II ≈ 1 : 1.

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Liquid‐liquid equilibria (LLE) data for the heptane‐methanol‐toluene‐calcium chloride and ethyl acetate‐water‐ethanol‐calcium chloride quaternary systems were measured under various salt concentrations at 298.15 K and the results obtained were correlated with a modification of Hàla's model. Distribution of the salt between the two liquid phases was found to be strongly influenced by the content of methanol or ethanol while the solubility of the salt in the heptane or ethyl acetate rich phase was very small. The two‐liquid region, i.e. the miscibility gap was enlarged by adding the salt. Correlations of LLE data including the salt distribution for both the non‐aqueous and aqueous quaternary systems were possible with reasonable accuracy.