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Chinese tallow tree (TT) seeds are a rich source of lipids and have the potential to be a biodiesel feedstock, but currently, its invasive nature does not favor large scale cultivation. Being a nonfood material, they have many advantages over conventional crops that are used for biodiesel production. The purpose of this study was to determine optimal oil extraction parameters in a batch-type and laboratory scale continuous-flow microwave system to obtain maximum oil recovery from whole TT seeds using ethanol as the extracting solvent. For the batch system, extractions were carried out for different time-temperature combinations ranging from 60 to 120 degrees C for up to 20 min. The batch system was modified for continuous extractions, which were carried out at 50, 60, and 73 degrees C and maintained for various residence times of up to 20 min. Control runs were performed under similar extraction conditions and the results compared well, especially when accounting for extremely short extraction times (minutes vs hours). Maximum yields of 35.32% and 32.51% (by weight of dry mass) were obtained for the continuous and batch process, respectively. The major advantage of microwave assisted solvent extraction is the reduced time of extraction required to obtain total recoverable lipids, with corresponding reduction in energy consumption costs per unit of lipid extracted. This study indicates that microwave extraction using ethanol as a solvent can be used as a viable alternative to conventional lipid extraction techniques for TT seeds.

Non-isocyanate polyurethanes (NIPU) have rapidly emerged as a sustainable, less toxic, and environmentally friendly alternative to traditional isocyanate-based thermoplastic polyurethane (TPU) synthesis. TPU is widely used in the medical industry due to its excellent mechanical properties and elasticity. However, little work has been done to synthesize and electrospin NIPU into fibrous mats for biomedical applications. In this work, melt polymerization of a plant oil-based cyclic carbonate monomer with polyether soft segments and various diamines yielded isocyanate-free, segmented poly(amide hydroxyurethane)s (PAHUs). Electrospinning of segmented PAHUs afforded ductile, free-standing fibrous mats with Young's modulus values between 7 and 8 MPa, suitable for tissue scaffold applications. PAHU fiber mats exhibited 3-4 times greater water uptake than the electrospun TPU control, demonstrating potential utility in drug delivery. Fibroblasts adhered to electrospun PAHU fibrous mats with viability values over 90% after 72-h, validating its biocompatibility. The results highlight the high performance and potential of electrospun isocyanate-free polyurethanes mats for biomedical application.

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BACKGROUND Aconitic acid (propene‐1, 2, 3‐ tricarboxylic acid) is the most prevalent organic acid found in sugar cane. It is used in the food processing industry as an acidulant and can be used in the synthesis of plasticizers. It can also be used to synthesize biodegradable polyesters for tissue engineering applications. In this study, aconitic acid was isolated from sugarcane molasses via liquid–liquid extraction with ethyl acetate. Six combinations of time and temperature (1–6 h at either 30 or 40°C) were tested. In order to conserve solvent, ethyl acetate was recovered and reused for subsequent extractions. The recovery of aconitic acid from vinasse was also evaluated. RESULTS Under the most efficient set of conditions, 69% of the aconitic acid was recovered as free acid. The purity (HPLC) of the extracted acid was found to be 99.9%. Ethanol was an additional stream that was generated by fermentation of molasses and yields of 12.4% (g per 100 g of molasses) were obtained. CONCLUSION The yield of aconitic acid from molasses varied from 34–69%, depending on the extraction conditions, with purity of the extracted acid being 99.9%. The aconitic acid is of a quality sufficient to synthesize polymers that could realize high‐value in biomedical applications. © 2013 Society of Chemical Industry

BACKGROUND In this study, polyesters of glycerol, aconitic acid and cinnamic acid were synthesized and studied for their potential application as scaffolds in tissue engineering. Aconitic acid can be recovered from molasses, while glycerol and cinnamic acid can be recovered from pretreated sugarcane bagasse used for bio‐ethanol production. Polyester synthesis was carried out at different molar ratios of reactants at a temperature of 120 °C for 5 h. Synthesized polyesters were characterized chemically and mechanically, and evaluated for their cytotoxicity and chemical stability towards human adipose derived mesenchymal pluripotent stem cells (hASC). RESULTS Several cytocompatibility tests such as mass loss over a period of time, alamar blue to analyze growth and viability of hASC on polyester scaffolds, picogreen for total DNA content synthesized, indicated that these polyesters hold promise as tissue engineering scaffolds. For skin tissue engineering, especially for wound repair, thin film polyester scaffolds laden with hASC were grown in stromal medium supplemented with basic fibroblast growth factor (bFGF). For all the scaffolds, the amount of collagen synthesized in bFGF supplemented medium was significantly higher than the scaffolds with hASC in control (stromal) medium (P<0.05) CONCLUSION Based on the amount of collagen synthesized and DNA quantification data, it was concluded that the polyesters are cytocompatible and support fibroblastic differentiation by the addition of bFGF. © 2015 Society of Chemical Industry