Shapirolancaster4452

A novel closed-loop biorefinery model using carob pods as the feed material was developed for PHB production. The carob pods were delignified, and as the second step, sugars present in the delignified carob pods were extracted using water. Ralstonia eutropha and Bacillus megaterium were cultivated on the carob pod extract and its performance was evaluated using Taguchi experimental design. R. eutropha outperformed the B. megaterium in terms of its capability to grow at a maximum initial sugar concentration of 40 g L-1 with a maximum PHB production of 12.2 g L-1. Finally, the concentrated lignin from the first step was diluted with different proportion of chloroform to extract PHB from the bacterial biomass. The PHB yield and purity obtained were more than 90% respectively using either R. eutropha or B. megaterium. Properties of the PHB produced in this study were examined to establish its application potential. Diatom algae can produce bioactive compounds like fucoxanthin (FX) and ecosapentaenoic acid (EPA) which are of high demand in pharmaceutical and nutraceutical industries. Here, the influence of different light regimes in combination with major nutrients on growth, FX and EPA production by marine diatom Thalassiosira weissflogii were investigated. Batch cultures of T. weissflogii were illuminated under blue (BL), red (RL) and white (WL) light at two intensities. BL regime resulted in higher cell density with a specific growth rate of 2.49µ. Lipid productivity and lipid % as dry cell weight (DCW) was considerably higher in BL with EPA productivity of 33.4 mg L-1d-1. Fucoxanthin content as % DCW reached 0.95 (BL), 0.75 (RL) and 0.81 (WL) at mid exponential growth phase. The results further prove the plasticity of diatoms and provide a way for future metabolic engineering of T. weissflogii for potential microalgal bio-refinery for combined EPA and FX production. The use of acetate as carbon feedstock can enhance sustainability and economics of the current bio-productions. IACS-13909 concentration This study explored the potential of acetate for the production of 3-hydroxypropionic acid by engineered Pseudomonas denitrificans. Heterologous mcr (encoding malonyl-CoA reductase) from Chloroflexus aurantiacus and endogenous accABCD (encoding acetyl-CoA carboxylase) were overexpressed in P. denitrificans. Carbon flux to 3-HP synthesis at the malonyl-CoA node was promoted by suppressing fatty acid synthesis through addition of cerulenin or deletion of fabF gene. In addition, stimulation of glyoxylate shunt and/or TCA cycle were attempted. Recombinant P. denitrificans overexpressing mcr and accABCD produced 19.3 mM 3-HP with cerulenin addition, and 14.2 mM with fabF deletion, respectively. Furthermore, the non-growing cells devoid of fabF could continuously produce 3-HP up to 40.4 mM without losing its production activity for 22 h. This study demonstrates that acetate is a good substrate for 3-HP production by recombinant P. denitrificans. Waste eggshell-derived bioflocculant was used for harvesting T. obliquus in a circular bioeconomy approach. It was found that 120 mg L-1 bioflocculant can flocculate 98.62 ± 0.43% of T. obliquus cells within 25 min at optimal pH 4.0 and temperature 35 °C. The influence of bioflocculant concentration, pH and temperature on zeta potential was evaluated to understand the flocculation mechanism. Microscopic and FESEM-EDX images were analyzed to evaluate the microalgal structural changes. Adsorption mechanism of bioflocculant over the microalgal cells was determined by performing adsorption kinetic studies. Pseudo-second order kinetic model was a suitable fit for the data obtained from the experiments, which indicated chemisorption as the probable mechanism. The spent medium recovered after harvesting process was successfully recycled for subsequent cultivation of T. obliquus, thus reducing the dependency on fresh medium. The FAME composition of the biomass treated with bioflocculant was not altered. Effective removal of alkali and alkaline earth metals (AAEM) is of great significance for promoting biomass pyrolysis. In this study, demineralization via hydrothermal pretreatment was performed, and the effect on the pyrolysis behavior was evaluated by thermogravimetric analysis (TGA) and thermal pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). The effects of reaction temperature, time, and pH on the dissolution rate of K+, Ca2+, and Mg2+ were investigated. The optimal total dissolution rate of the metal elements was 42.10%. Compared with acid leaching, hydrothermal pretreatment allowed a higher crystallinity index. It significantly changed the pyrolysis behavior. The relative content of sugar in pyrolysis products was as high as 58%. The chemical compound distribution was concentrated in the range between C6 and C9, which was conducive for the refinement of gasoline by upgrading. This means that hydrothermal pretreatment has efficient demineralization, which promoted the thermal degradation behavior of biomass. A major issue hindering development of thin film nanocomposite (TFN) nanofiltration (NF) membrane is the interfacial defects induced by nanomaterial aggregation in top layer. Although various nanomaterials surface modification strategies have been developed to eliminate the interfacial defects, they usually involve extra modification steps and complex post-treatments. Inspired by the substrate-independent coating ability of tannic acid (TA) and the fact that the phenolic hydroxyl groups in TA can react with acyl chloride group in trimesoyl chloride, a TA coating solution containing TiO2 nanoparticles was used as an aqueous phase of interfacial polymerization to prepare interfacial modified TFN NF membranes in this study. Surface modification of TiO2 nanoparticles and interfacial polymerization can be carried out in a single step without any extra pre-modification step. It was found that the TA coating on TiO2 nanoparticles surface could decrease TiO2 aggregations and enhance interfacial compatibility between TiO2 and polyester matrix. The TFN NF membrane prepared at a TiO2 loading of 0.020 wt% exhibited a pure water flux of 28.8 L m-2 h-1 (284% higher than that of the controlled TFC membrane), and possessed enhanced NaCl and Na2SO4 rejections of 57.9% and 94.6%, respectively, breaking through the trade-off between permeability and selectivity.