The ability of deep eutectic solvent systems to extract bioactive compounds from apple pomace.

The objective of this study was to examine the bioactivity of extracts from apple pomace obtained by non-conventional green extraction methods (DES systems). Bioactivity was antioxidant capacity and ability to stimulate insulin secretion from pancreatic beta-cells. The antioxidant capacity of extracts was examined using the DPPH and the FRAP assay. Impact of the extracts on cell viability and insulin secretion were examined using the BRIN-BD11 cell line. ChCl:EG(1:4) extracts resulted in high antioxidant capacity in the DPPH assay (80.1% inhibition versus 11.3%). Extracts obtained from the classical systems demonstrated an ability to promote insulin secretion significantly higher than the positive control, p < 0.05. ChCl:EG(1:4) extracts stimulated insulin secretion to a lesser extent. Overall, the data provides evidence for the potential of DES systems to extract bioactive compounds from apple pomace that have relevance for metabolic health. Further optimisation of the extraction procedures should be tailored to the desired bioactive properties.

Technological application potential of polyethylene and polystyrene biodegradation by macro-organisms such as mealworms and wax moth larvae.

Multiple recent reports showed accelerated biodegradation of polyethylene by employing macro-organisms such as mealworms (Tenebrio molitor) and larvae of the greater wax moth (Galleria mellonella), which seemingly chew and digest the plastic. Nevertheless, doubts regarding analytical data were published, and results are not universally transferrable. This paper aims at gaining mechanistic insights and exploring the technological prospects of potential future optimized biodegradation. We used a variety of experimental setups with both species, using both live specimens and homogenated paste, to cover a broad spectrum of potential technological setups, and performed gravimetric, microscopic and spectroscopic analyses. Live larvae showed a preference for specific substrates, yet we argue by comparison to other food sources, evidenced also by energetic uptake, that a diet of LDPE is insufficient for growth. We did not detect mass loss when homogenate paste is brought in contact with LDPE films, nor significant traces of ethylene glycol. We demonstrated that the morphology of the substrate changes after contact with live larvae, indicating some plasticizing action by an excreted liquid. This indicates a mechanism of degradation involving more than the gut microbiome alone. Using streamlined life cycle assessment and techno-economic analysis (LCA/TEA) methods, we showed that the application of these findings as either a remediation or management technology for waste plastics is highly unlikely, given the conversion to microplastics, the absence of valuable products, and the high energy cost. However, the conversion mechanism should be further elucidated for bio-functionalization of liquid alkanes as high-value application, or to mitigate plastic anomalies in composting/digesting food waste.

Enzymatically Modified Fats Applied in Emulsions Stabilized by Polysaccharides.

The subject of the study was emulsions based on enzymatically modified fats and stabilized with polysaccharides (xanthan gum and scleroglucan). Emulsion oil phases (blends of mutton tallow and hemp seed oil in a ratio of 3:1, 3:2, 3:3, 2:3 and 1:3) were characterized in the terms of acid value, melting point and mono- and diacylglycerols content before and after the modification. Emulsions containing modified fat blends and various amount (0.6, 0.8 and 1.0% w/w) of polysaccharides were investigated in the terms of their color, rheological properties, microstructure, droplet size and stability. The obtained results confirmed that enzymatic modification allowed to produce new fats, which can successfully be applied as an emulsion oil phases equipped with a sufficient amount of emulsifiers. The use of a variable amount of texture modifier in the proposed formulations did not show clear differences in the stability of the systems. Therefore, it does not seem justified to use greater amounts of a modifier (above 0.6% w/w) in this type of emulsions. The proposed formulations could be of interest to the cosmetics, food or pharmaceutical industry.

Low-temperature chemical synthesis of high-purity diacylglycerols (DAG) from monoacylglycerols (MAG).

A chemical method was developed for low-temperature synthesis of DAG from MAG followed by an easy purification procedure in order to obtain high-purity DAG. Solvent-assisted and solvent-free reaction conditions were used, combined with different catalysts (sodium methoxide, p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid). All reactions were performed at 35 and 70 °C. By increasing both acidity and polarity of the catalyst the equilibrium shifts towards the formation of DAG. When using sulfuric acid in solvent-assisted condition at 70 °C, 88% conversion was obtained after 20 min of reaction (77% w/w DAG in the reaction mixture after evaporation of the solvent). After purifying by means of column chromatography, 96% pure DAG were obtained. The overall yield of DAG was 81%.