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A strain JX23 was isolated from soil and identified as a species of Mucor according to the morphological characteristics and the nuclear ribosomal internal transcribed spacer sequence and designated as Mucor sp. JX23. Biotransformations of cinnamaldehyde (CMD), cinnamic acid (CMA) and acetophenone (ACP) catalyzed by JX23 were investigated. After JX23 was cultured for 48 h, the substrates CMD, CMA and ACP were added to the growth medium respectively and the products were analyzed by GC-MS and HPLC. Mucor sp. JX23 exhibited considerable redox capability and different catalytic specificity to CMD, CMA and ACP. CMD was selectively hydrogenated to cinnamyl alcohol. CMA was biotransformed to ACP with a, b-oxidation like degradation, and ACP could not be reduced further by JX23. When ACP was added as substrate, it could be asymmetrically reduced to (S)-(-)-1-phenylethyl alcohol (S-PEA) with high stereoselectivity (90%). Further, the biotransformations of different binary mixture substrates with JX23 were also studied. The biocatalytic selectivity depended on the relationship between the binary mixtures in above-mentioned reaction.

The kinetics and thermodynamics of the adsorption process of reserpine adsorbed onto the strong acidic cationic exchange fiber (SACEF) were studied by batch adsorption experiments. The adsorption capacity strongly depended on pH values, and the optimum reserpine adsorption onto the SACEF occurred at pH = 5 of reserpine solution. With the increase of temperature and initial concentration, the adsorption capacity increased. The equilibrium was attained within 20 mins. The adsorption process could be better described by the pseudo-second-order model and the Freundlich isotherm model. The calculated activation energy Ea was 4.35 kJ/mol. And the thermodynamic parameters were: 4.97<ΔH<7.44 kJ/mol, -15.29<ΔG<-11.87 kJ/mol and 41.97<ΔS<47.35 J/mol·K. The thermodynamic parameters demonstrated that the adsorption was an endothermic, spontaneous and feasible process of physisorption within the temperature range between 283 K and 323 K and the initial concentration range between 100 mg/L and 300 mg/L. All the results showed that the SACEF had a good adsorption performance for the adsorption of reserpine from alcoholic solution.

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The thermal oxidation characteristics of abietic acid were investigated through tracing the oxidation process in custom-designed mini closed pressure vessel test under isothermal and step temperature conditions. Peroxide generation and the peroxide value of abietic acid oxidation process were measured using thin-layer chromatographic analysis and iodimetry. The primary oxidation productperoxidewas separated by column chromatography with further structure characterization, and its thermal decomposition characteristics were assessed via a differential scanning calorimeter (DSC). The oxidation was mainly initiated through the radical generation from hydrogen abstraction on the unsaturated conjugated double bonds of abietic acid above 343 K. The main hydroperoxide, 7-hydroperoxy-13-abiet-8(14)-enoic acid, was found in abietic acid with a high peroxide value. The exothermic onset temperature (T 0) and decomposition heat (Q DSC) of this peroxide were 353.94 K and 545.37 J·g–1, respectively. Finally, a second-stage oxidation process of abietic acid was first investigated when the temperature reached the abietic acid melt point (448 K) with complex oxidation products forming, such as dehydroabietic acid, palustric acid, 7-oxodehydroabietic acid, neoabietic acid, 7-methoxy-tetradehydroabietic acid, 12-deoxyroyleanone acid, and 12-methoxy-abietic acid.