Agarose/κ-carrageenan-based hydrogel film enriched with natural plant extracts for the treatment of cutaneous wounds.

Hydrogels for complex and chronic wound dressings must be conformable, absorb and retain wound exudates and maintain hydration. They can incorporate and release bioactive molecules that can accelerate the healing process. Wound dressings have to be in contact with the wound and epidermis, even for long periods, without causing adverse effects. Hydrogel dressing formulations based on biopolymers derived from terrestrial or marine flora can be relatively inexpensive and well tolerated. In the present article hydrogel films composed by agarose (1.0 wt%), κ-carrageenan at three different concentrations (0.5, 1.0 and 1.5 wt%) and glycerol (3.0 wt%) were prepared without recourse to crosslinking agents, and characterized for their mechanical properties, morphology, swelling and erosion behavior. The films resulted highly elastic and able to absorb and retain large amounts of fluids without losing their integrity. One of the films was loaded with the aqueous extract from Cryphaea heteromalla (Hedw.) D. Mohr for its antioxidant properties. Absence of cytotoxicity and ability to reduce the oxidative stress were demonstrated on NIH-3T3 fibroblast cell cultures. These results encourage further biological evaluations to assess their impact on the healing process.

Water Extract of Cryphaea heteromalla (Hedw.) D. Mohr Bryophyte as a Natural Powerful Source of Biologically Active Compounds.

Bryophytes comprise of the mosses, liverworts, and hornworts. Cryphaea heteromalla, (Hedw.) D. Mohr, is a non-vascular lower plant belonging to mosses group. To the date, the most chemically characterized species belong to the liverworts, while only 3.2% and 8.8% of the species belonging to the mosses and hornworts, respectively, have been investigated. In this work, we present Folin-Ciocalteu and oxygen radical absorbance capacity (ORAC) data related to crude extracts of C. heteromalla obtained by three different extraction solvents: pure water (WT), methanol:water (80:20 v/v) (MET), and ethanol:water (80:20 v/v) (ETH). The water extract proved to be the best solvent showing the highest content of biophenols and the highest ORAC value. The C. heteromalla-WT extract was investigated by HPLC-TOF/MS (High Performance Liquid Chromatography-Time of Flight/Mass Spectrometry) allowing for the detection of 14 compounds, five of which were phenolic compounds, derivatives of benzoic, caffeic, and coumaric acids. Moreover, the C. heteromalla WT extract showed a protective effect against reactive oxygen species (ROS) generation induced by tert-butyl hydroperoxide (TBH) on the murine NIH-3T3 fibroblast cell line.

Biochemical and biophysical characterization of water-soluble pectin from Opuntia ficus-indica and its potential cytotoxic activity.

This work aims to fill the gap in the present knowledge about the structure of pectin from Opuntia ficus-indica. The water-soluble pectin (WSP) fraction, extracted with the Microwave Assisted Extraction (MAE), was further deproteinated (dWSP) and analyzed through several biophysical and biochemical techniques. HPSEC, light scattering and FTIR data showed that dWSP is low methylated high molecular weight pectin. The biochemical structure of dWSP, after methanolysis, silylation, carboxyl reduction showed that dWSP belongs to rhamnogalacturonan I class. Then, dWSP was heat-modified (HM) to obtain small-molecular weight deproteinated fraction (HM-dWSP). Both species, dWSP and HM-dWSP, were tested in LAN5 and NIH 3T3 model cells to study their biological effect. Results indicated that both dWSP and HM-dWSP exerted cytotoxic activity affecting selectively LAN5 cancer cells, without any effect on NIH 3T3 normal cells.

Pectin from Opuntia ficus indica: Optimization of microwave-assisted extraction and preliminary characterization.

Optimization of microwave-assisted extraction (MAE) of water-soluble pectin (WSP) from Opuntia ficus indica cladodes was performed using Response Surface Methodology. The effect of extraction time (X1), microwave power (X2), pH (X3) and solid-to-liquid ratio (X4) on the extraction yield was examined. The optimum conditions of MAE were as follows: X1=2.15min; X2=517W; X3=2.26 and X4=2g/30.6mL. The maximum obtained yield of pectin extraction was 12.57%. Total carbohydrate content of WSP is about 95.5% including 34.4% of Galacturonic acid. Pectin-related proteins represent only the 0.66% of WSP mass. HPSEC and light scattering analyses reveal that WSP is mostly constituted of high molecular pectin and FTIR measurements show that the microwave treatment does not alter the chemical structure of WSP, in which Galacturonic acid content and yield are 34.4% and 4.33%, respectively. Overall, application of MAE can give rise to high quality pectin.

The allergens of Parietaria.

Parietaria is a genus of dicotyledonous weeds of the Urticaceae family including several species and its pollen grain is one of the most important allergenic sources in the Mediterranean area. Species belonging to this genus induce IgE responses in approximately 10 million people. Identification of allergens by means of independent strategies suggest that the allergens of the two more common species, Parietaria judaica and Parietaria Officinalis, show molecular weights ranging between 10 and 14 kD and that the allergens of the two extracts are highly cross-reactive. Biochemical analysis and molecular cloning allowed the isolation and immunological characterization of the two major allergens of the P. judaica pollen, Par j 1 and Par j 2. Sequence comparison suggests that the P j major allergens of P. Judaica belong to the nonspecific lipid transfer protein family, and three-dimensional modeling by homology has revealed that both proteins present a very conserved structural motif composed of four alpha-helices. Immunological analysis has shown that Par j 1 and Par j 2 are able to bind most of the P. Judaica-specific IgE and some of their IgE determinants have been mapped. Recombinant Par j 1 and Par j 2 allergens have been shown to possess immunological properties equivalent to their natural counterpart and their availability represents a fundamental tool for the diagnosis and therapy of Parietaria pollen allergy.