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5-hydroxymethylfurfural (HMF) is a platform chemical that can be converted into a wide range of high-value derivatives. Industrially, HMF-based derivatives are synthesized via chemical catalysis. However, biocatalytic transformation has emerged as an attractive alternative. Significant advances have been made in the last years using isolated enzymes and whole-cell biocatalysts in HMF biotransformation. Nonetheless, one of the major bottlenecks is the cost of the process, mainly due to the microorganism growth substrate. In this work, biotransformation studies to transform HMF into 2,5-di(hydroxymethyl)furan (DHMF) were carried out with the fungus Fusarium striatum using low-cost protein hydrolysates. The protein hydrolysates were obtained from fines, an unexploited material produced during the rendering process of meat industry waste residues. Given the high content in the protein of fines, of around 46%, protein hydrolysis was optimized using two commercially available proteases, Alcalase 2.4 L and Neutrase 0.8 L. The maximum degree of hydrolysis (DH) achieved with Alcalase 2.4 L was 21.4% under optimal conditions of 5% E/S ratio, pH 8, 55 °C, and 24 h. On the other hand, Neutrase 0.8 L exhibited lower efficiency, and therefore, lower protein recovery. After optimization of the Neutrase 0.8 L process using the response surface methodology (RSM), the maximum DH achieved was 7.2% with the variables set at 15% E/S ratio, initial pH 8, 40 °C, and 10.5 h. Using these hydrolysates as a nitrogen source allowed higher sporulation of the fungus and, therefore, the use of a lower volume of inoculum (three-fold), obtaining a DHMF yield > 90%, 50% higher than the yield obtained when using commercial peptones. The presented process allows the transformation of animal co- and by-products into low-cost nitrogen sources, which greatly impacts the industrial feasibility of HMF biotransformation.

Within the framework of the development of the Algerian flora, the seriousness of the damage caused by aphids of which the species Chaitophorus populialbae Boyer de Fonscolombe, infested the white poplar and the search for alternative solutions more respectful for the environment relying on the role of biopesticides of plant origin, we chose a plant Pteridium aquilinum Linné, belonging to the family Dennstaedtiaceae which presents various biological activities, in particular insecticide. This study is intended to improve our knowledge of these chemical compounds. and evaluate the insecticide activity in vitro, in laboratory conditions, of this plant's methanolic and chloroformic extracts on viviparous apterous females of Chaitophorus populialbae Boyer de Fonscolombe. The best extraction yield of the plant was recorded with the polar solvent methanolic with a rate of 50.5% compared to chloroform, whose extraction rate was 43.5%. The chemical compounds identified by GC/MS are 29 from the ultrasound extraction. Among the 29 chemical compounds, 21 are terpenes, including 6 monoterpenes and 8 oxygenated monoterpenes, 7 fatty acids, and 1 amino acid. Toxicity tests of methanolic and chloroformic extracts, at a concentration of 50 µL/mL reveal corrected mortality of 100% after 24 h of exposure for all the viviparous apterous females of Chaitophorus populialbae Boyer de Fonscolombe.

Nine monoamides were synthesized from carboxylic acids (C8–C18) and crude glycerol. The final monoamides were the result of a rearrangement of the acyl chain during the final hydrogenation process. The purity of the final compounds was determined by spectroscopic and mass spectrometry (MS) techniques. The thermophysical properties of solid monoamides were investigated to determine their capability to act as phase change materials (PCM) in thermal energy storage. Thermophysical properties were determined with a differential scanning calorimeter (DSC). The melting temperatures of the analyzed material ranged from 62.2 °C to 116.4 °C. The analyzed enthalpy of these monoamides ranged from 25.8 kJ/kg to 149.7 kJ/kg. Enthalpy values are analyzed considering the carbon chain and the formation of hydrogen bonds., Postprint (published version)