Investigation of the phytochemical composition, antioxidant, antibacterial, anti-osteoarthritis, and wound healing activities of selected vegetable waste.

Agri-food wastes, produced following industrial food processing, are mostly discarded, leading to environmental hazards and losing the nutritional and medicinal values associated with their bioactive constituents. In this study, we performed a comprehensive analytical and biological evaluation of selected vegetable by-products (potato, onion, and garlic peels). The phytochemical analysis included UHPLC-ESI-qTOF-MS/MS in combination with molecular networking and determination of the total flavonoid and phenolic contents. Further, the antimicrobial, anti-osteoarthritis and wound healing potentials were also evaluated. In total, 47 compounds were identified, belonging to phenolic acids, flavonoids, saponins, and alkaloids as representative chemical classes. Onion peel extract (OPE) showed the higher polyphenolic contents, the promising antioxidant activity, the potential anti-osteoarthritis activity, and promising antimicrobial activity, especially against methicillin-resistant Staphylococcus aureus (MRSA). Furthermore, OPE revealed to have promising in vivo wound healing activity, restoring tissue physiology and integrity, mainly through the activation of AP-1 signaling pathway. Lastly, when OPE was loaded with nanocapsule based hydrogel, the nano-formulation revealed enhanced cellular viability. The affinities of the OPE major metabolites were evaluated against both p65 and ATF-2 targets using two different molecular docking processes revealing quercetin-3,4'-O-diglucoside, alliospiroside C, and alliospiroside D as the most promising entities with superior binding scores. These results demonstrate that vegetable by-products, particularly, those derived from onion peels can be incorporated as natural by-product for future evaluation against wounds and osteoarthritis.

Folate-chitosan nanoparticles triggered insulin cellular uptake and improved in vivo hypoglycemic activity.

The aim of this study was to prove a prolonged control of glucose levels, in rats, by the oral use of insulin folate-chitosan nanoparticles (FA-CS NPs). It was possible to prepare positively charged NPs with an average particle size of 288 ±â€¯5.11 nm and >80% entrapment efficiency. The system was able to enhance the stability of insulin in presence of GIT enzymes, with less than 10% release at pH 1.2 and an 8 hr released amount of 38.92 ±â€¯4.52% in PBS pH 7.4. A 5 fold enhancement in insulin intestinal permeability and cellular uptake over insulin solution was proven. The cellular uptake pathways was found to occur by several mechanisms. Besides, cell compatibility and absence of histopathological alterations was also demonstrated. Finally, a controlled blood glucose level for 8 h in rats. These results anticipated FA-CS NPs as a promising oral insulin candidate.