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5-hydroxymethylfurfural (HMF) stands out among the chemical products derived from biomass as a building block in the chemical industry. The conventional production of HMF is usually carried out from fructose, glucose, or other monosaccharides as feedstock, but sugar beet molasses, a by-product of the sugar industry containing sucrose (45–55%), is promising. This exploratory study used three aqueous stock solutions and one biphasic system as the sources of sucrose. The dehydration of sucrose to 5-hydroxymethylfurfural was assisted by microwave heating and subcritical water conditions. The maximum yield of HMF was 27.8 mol % for the aqueous solution of synthetic sucrose at 80 min of treatment. Although HMF yield was 7.1 mol % in the aqueous sugar beet molasses solution, it increased 2-fold after clarification (15.1 mol %) and 1.6-fold in the biphasic system (11.4 mol %). These are favorable outcomes since this is an exploratory investigation. The pseudo-first-order model fitted experimental data from the conversion of the sucrose from the stock solutions, and kinetic parameters were estimated and compared. The estimated reaction rate constant showed that inversion of sucrose is faster than fructose dehydration to HMF, but the latter reaction was the rate-determining step only for the biphasic system. The maximum partition coefficient value was four between 40 min and 60 min of reaction, calculated at room temperature. These predictions help investigators to estimate conversions and selectivity when pilot plants need to be simulated. [ABSTRACT FROM AUTHOR]

Castor bean is found in Chile between the Arica and Parinacota and Maule regions and is one the most important industrial crops worldwide because of the presence of ricinoleic acid in its oil. However, there is little information about it in our country. In this study, we analyzed the oil content and fatty acid profiles of 17 castor bean Chilean accessions from the Metropolitana and Valparaíso regions. The seed-oil was extracted using the Soxhlet extraction process, and the fatty acid profiles were determined using the GC-FID method. The oil content in castor bean Chilean accessions ranged between 45.7% and 54.0%. Among the 17 accessions analyzed, H-15 had the highest oil content (54.0%; p < 0.05), whereas the H-10 and H-08 accessions had the lowest oil content, (45.7% and 45.9%, respectively; p < 0.05). Ricinoleic acid was the most abundant fatty acid (between 87.64% and 89.83%) in the seed-oil. The highest level of ricinoleic acid was found in the H-08 accession. This was only statistically higher (p < 0.05) for three accessions, whereas the H-04 accession had the lowest ricinoleic acid content. Although the H-08 accession registered one of the least abundant oil contents, it had the highest amount of ricinoleic acid. No significant correlation was found between oil content and ricinoleic acid. Our study suggests that oil content does not influence the castor oil fatty profile. The high oil content and ricinoleic acid level registered in castor bean Chilean accessions justify their production in Chile and their utilization for developing bio-based products. Furthermore, Chilean castor bean could grow in semi-arid lands. However, further field studies are needed to identify the cultivars best suited for Mediterranean conditions. [ABSTRACT FROM AUTHOR]

Antioxidants can be encapsulated to enhance their solubility or bioavailability or to protect them from external factors. Electrospinning has proven to be an excellent option for applications in nanotechnology, as electrospun nanofibers can provide the necessary environment for antioxidant encapsulation. Forty-nine papers related to antioxidants loaded onto electrospun nanofibers were categorized and reviewed to identify applications and new trends. Medical and food fields were commonly proposed for the newly obtained composites. Among the polymers used as a matrix for the electrospinning process, synthetic poly (lactic acid) and polycaprolactone were the most widely used. In addition, natural compounds and extracts were identified as antioxidants that help to inhibit free radical and oxidative damage in tissues and foods. The most recurrent active compounds used were tannic acid (polyphenol), quercetin (flavonoid), curcumin (polyphenol), and vitamin B6 (pyridoxine). The incorporation of active compounds in nanofibers often improves their bioavailability, giving them increased stability, changing the mechanical properties of polymers, enhancing nanofiber biocompatibility, and offering novel properties for the required field. Although most of the polymers used were synthetic, natural polymers such as silk fibroin, chitosan, cellulose, pullulan, polyhydroxybutyrate, and zein have proven to be proper matrices for this purpose. [ABSTRACT FROM AUTHOR]