Benign-by-Design SAHA Analogues for Human and Animal Vector-Borne Parasitic Diseases

The search for new drugs fulfilling One Health and Green Chemistry requirements is an urgent call. Here, for the first time, we envisaged developing SAHA analogues by starting from the cashew nutshell liquid (CNSL) agro-industrial waste and employing a metathesis approach. This sustainable combination (comprising principles #7 and #9) allowed a straightforward synthesis of compounds 13-20. All of them were found to not be toxic on HepG2, IMR-32, and L929 cell lines. Then, their potential against major human and animal vector-borne parasitic diseases (VBPDs) was assessed. Compound 13 emerged as a green hit against the trypomastigote forms of T. b. brucei. In silico studies showed that the T. b. brucei HDAC (TbDAC) catalytic pocket could be occupied with a similar binding mode by both SAHA and 13, providing a putative explanation for its antiparasitic mechanism of action (13, EC50 = 0.7 ± 0.2 μM).

Synthesis and Properties of Polystyrene Composite Material with Hazelnut Shells

In this study we evaluated the potential use of hazelnut shell powder in the production of a composite material. Polystyrene was used as a polymer matrix. This work presents the results of modifying hazelnut powder particles to create a polystyrene shell on their surfaces. Modification of the filler increased its contact angle wetted with water from θ=60.16±1.03° to θ=87.02±1.10°. Composite materials containing from 10 to 50 wt.% of modified hazelnut shell powder were prepared and studied. As a result of the experiments, it was found that the composites have optimal physical, mechanical, and operational properties at the following ratio: polystyrene 60-80 wt.%, modified hazelnut shell powder 20-40 wt.%. If the introduction of polystyrene was more than 90 wt.%, the flexural strength and Vickers hardness were quite low at the load of 200 g, and accordingly, the durability of such materials was not satisfactory. These samples are characterized by small percentages of hazelnut shells; therefore, the resulting material will be of pale, unsaturated color. The upper limit of the working temperature range for the composite lies between 265.0-376.0 °C, depending on the percentage of the hazelnut shell powder filling.

Making natural products from renewable feedstocks: back to the roots?

This review highlights the utilization of biomass-derived building blocks in the total synthesis of natural products.

Natural Phenol Polymers: Recent Advances in Food and Health Applications

Natural phenol polymers are widely represented in nature and include a variety of classes including tannins and lignins as the most prominent. Largely consumed foods are rich sources of phenol polymers, notably black foods traditionally used in East Asia, but other non-edible, easily accessible sources, e.g., seaweeds and wood, have been considered with increasing interest together with waste materials from agro-based industries, primarily grape pomace and other byproducts of fruit and coffee processing. Not in all cases were the main structural components of these materials identified because of their highly heterogeneous nature. The great beneficial effects of natural phenol-based polymers on human health and their potential in improving the quality of food were largely explored, and this review critically addresses the most interesting and innovative reports in the field of nutrition and biomedicine that have appeared in the last five years. Several in vivo human and animal trials supported the proposed use of these materials as food supplements and for amelioration of the health and production of livestock. Biocompatible and stable functional polymers prepared by peroxidase-catalyzed polymerization of natural phenols, as well as natural phenol polymers were exploited as conventional and green plastic additives in smart packaging and food-spoilage prevention applications. The potential of natural phenol polymers in regenerative biomedicine as additives of biomaterials to promote growth and differentiation of osteoblasts is also discussed.

Bio-Based Aromatic Epoxy Monomers for Thermoset Materials

The synthesis of polymers from renewable resources is a burning issue that is actively investigated. Polyepoxide networks constitute a major class of thermosetting polymers and are extensively used as coatings, electronic materials, adhesives. Owing to their outstanding mechanical and electrical properties, chemical resistance, adhesion, and minimal shrinkage after curing, they are used in structural applications as well. Most of these thermosets are industrially manufactured from bisphenol A (BPA), a substance that was initially synthesized as a chemical estrogen. The awareness on BPA toxicity combined with the limited availability and volatile cost of fossil resources and the non-recyclability of thermosets implies necessary changes in the field of epoxy networks. Thus, substitution of BPA has witnessed an increasing number of studies both from the academic and industrial sides. This review proposes to give an overview of the reported aromatic multifunctional epoxide building blocks synthesized from biomass or from molecules that could be obtained from transformed biomass. After a reminder of the main glycidylation routes and mechanisms and the recent knowledge on BPA toxicity and legal issues, this review will provide a brief description of the main natural sources of aromatic molecules. The different epoxy prepolymers will then be organized from simple, mono-aromatic di-epoxy, to mono-aromatic poly-epoxy, to di-aromatic di-epoxy compounds, and finally to derivatives possessing numerous aromatic rings and epoxy groups.