Liquid chromatography separation of α- and γ-linolenic acid positional isomers with a stationary phase based on covalently immobilized cellulose tris(3,5-dichlorophenylcarbamate).

α-Linolenic acid (ALA) and its most important positional isomer γ-linolenic acid (GLA), are essential fatty acids (vitamin F). Therefore, ALA- and GLA-rich edible oils hold great potential in human and animal nutrition, as well as in nutraceutics and cosmetics. Quality control and nutritional validation of oil products is thus of increasing importance. In the present study, the cellulose tris(3,5-dichlorophenylcarbamate)-based chiral stationary phase was successfully used for separation of ALA and GLA, a major challenge in the liquid chromatography of these isomers. The chromatographic conditions were firstly optimized on a HPLC system with UV detection, and the use of a reversed-phase eluent system made up of aqueous 10 mM ammonium acetate/acetonitrile (40/60, v/v; wspH6.0) with a 25 °C column temperature resulted optimal for the simultaneous discrimination of the two isomers at a 0.5 mL/min flow rate (α = 1.10; RS = 1.21). The method was then optimized for LC-MS/MS implementation. The proposed innovative separation method holds a great potential for the quantification of ALA and GLA in food and biological matrices, thus opening the way to further investigations involving the two positional isomers.

Preparation and characterization of polymeric microparticles loaded with Moringa oleifera leaf extract for exuding wound treatment.

The aim of this study was to develop an innovative formulation, particularly useful for the treatment of exuding wounds. An extract from Moringa oleifera leaves (MOE), prepared by an eco-friendly method, was used as active ingredient. Its preliminary characterization showed that MOE is rich in quercetin-O-glucoside and quercetin-O-malonyl glucoside, responsible for the antioxidant, radical scavenging and antibacterial activities (toward Staphylococcus aureus, S. epidermidis, S. faecalis and S. pyogenes). Moreover, MOE showed the ability to stimulate keratinocytes growth. Thus, bioadhesive biocompatible polymeric microparticles loaded with such extract were developed and prepared in order to treat exuding wounds. The microparticles, obtained by spray drying, using chitosan as polymer, showed good swelling ability. This is useful to obtain the transition from microparticles to a continuous gel covering the wound, after deposition on it. This has the double function to protect the damage area and to promote the healing. The in vitro release study showed that the formed gel is able to release immediately MOE, in the first minutes after application, and to promote a sustained release within 24 h reaching an efficacious concentration against the most sensitive bacterial strains. These findings suggest that the developed microparticles represent an interesting tool for exuding wounds treatment.