Rheology of highly-concentrated-in-oil emulsions

Dottorato di Ricerca in Ambiente, Salute e Processi Ecosostenibili Ciclo XXII,a.a. 2009-2010Università della Calabri

Nutraceuticals Obtained by SFE-CO2 from Cladodes of Two Opuntia ficus-indica (L.) Mill Wild in Calabria

The aim of the present study was to evaluate the possibility to extract, by supercritical fluids, nutraceuticals as polyphenolic compounds, able in the prevention and in the treatment of a series of chronic-degenerative diseases, from plant matrices like the cactus pear. Supercritical fluid technology is an innovative method to extract nutraceuticals from natural matrices. This method offers numerous advantages that include the use of moderate temperatures, solvents with good transport properties (high diffusivity and low viscosity), and cheap and nontoxic fluids. Fresh cladodes from two different wild ecotypes of Opuntia ficus-indica (L.) Mill. were extracted both with methanol and with SFE-CO2 using different samples preparations, to maximize the % yields and the selectivity of extraction of polyphenols. The biggest contents of phenolics, evaluated by Folin-Ciocalteu assay, has been observed with the sample dehydrated of O. ficus-indica cultivar that shows, as well, the best yield % (m/m) of extraction with both methanol and SFE-CO2. Better results were obtained with the samples of O. ficus-indica cult. (OFI cult.), in spite of the O. ficus-indica s.l. (OFI s.l.); the two different ecotypes of OFI showed dissimilar phytochemicals profile. We noticed that the reduction of both quantity and quality of polyphenols was drastic with the increase of pressure at 250 bar; this shows that high pressures result in a loss of bioactive principles, like polyphenols. By changing the variables of extraction processes with SFE-CO2 and by varying the preventive treatments of the natural matrices, it was possible to increase the selectivity and the purity of the products. Thus, the optimization of this useful and green technique allowed us to increase the value of the Opuntia cladodes, a by-product very diffused in Calabria, which is an extraordinary source of nutraceuticals. These extracts could be used directly as functional foods or as starting material in the pharmaceutical, nutraceutical or cosmetic companies; they are safe and without any solvents traces and it is possible to obtain it in a few hours respect to the conventional extraction that requires longer extraction time

Emulgels Structured with Dietary Fiber for Food Uses: A Rheological Model

Emulgels are biphasic emulsified systems in which the continuous phase is structured with a specific gelling agent. In this work, a rheological and microscopic investigation of O/W emulgels prepared by structuring the aqueous (continuous) phase with citrus fiber was carried out with the aim of designing their macroscopic properties for food uses and predicting their characteristics with a rheological model. According to previous investigations, fiber suspensions behave as “particle gels” and, consequently, the derived emulgels’ properties are strongly dependent on the fiber concentration and on process conditions adopted to produce them. Therefore, a rotor–stator system was used to prepare emulgels with increasing fiber content and with different levels of energy and power used for mixing delivered to the materials. An investigation of particle gels was then carried out, fixing the operating process conditions according to emulgel results. Furthermore, the effect of the dispersed (oil) phase volume fraction was varied and a modified semi-empirical Palierne model was proposed with the aim of optimizing a correlation between rheological properties and formulation parameters, fixing the process conditions

Nutraceuticals Obtained by SFE-CO2 from Cladodes of Two Opuntia ficus-indica (L.) Mill Wild in Calabria

The aim of the present study was to evaluate the possibility to extract, by supercritical fluids, nutraceuticals as polyphenolic compounds, able in the prevention and in the treatment of a series of chronic-degenerative diseases, from plant matrices like the cactus pear. Supercritical fluid technology is an innovative method to extract nutraceuticals from natural matrices. This method offers numerous advantages that include the use of moderate temperatures, solvents with good transport properties (high diffusivity and low viscosity), and cheap and nontoxic fluids. Fresh cladodes from two different wild ecotypes of Opuntia ficus-indica (L.) Mill. were extracted both with methanol and with SFE-CO2 using different samples preparations, to maximize the % yields and the selectivity of extraction of polyphenols. The biggest contents of phenolics, evaluated by Folin-Ciocalteu assay, has been observed with the sample dehydrated of O. ficus-indica cultivar that shows, as well, the best yield % (m/m) of extraction with both methanol and SFE-CO2. Better results were obtained with the samples of O. ficus-indica cult. (OFI cult.), in spite of the O. ficus-indica s.l. (OFI s.l.); the two different ecotypes of OFI showed dissimilar phytochemicals profile. We noticed that the reduction of both quantity and quality of polyphenols was drastic with the increase of pressure at 250 bar; this shows that high pressures result in a loss of bioactive principles, like polyphenols. By changing the variables of extraction processes with SFE-CO2 and by varying the preventive treatments of the natural matrices, it was possible to increase the selectivity and the purity of the products. Thus, the optimization of this useful and green technique allowed us to increase the value of the Opuntia cladodes, a by-product very diffused in Calabria, which is an extraordinary source of nutraceuticals. These extracts could be used directly as functional foods or as starting material in the pharmaceutical, nutraceutical or cosmetic companies; they are safe and without any solvents traces and it is possible to obtain it in a few hours respect to the conventional extraction that requires longer extraction time

Electrical storm treatment by percutaneous stellate ganglion block: the STAR study

Background and Aims An electrical storm (ES) is a clinical emergency with a paucity of established treatment options. Despite initial encouraging reports about the safety and effectiveness of percutaneous stellate ganglion block (PSGB), many questions remained unsettled and evidence from a prospective multicentre study was still lacking. For these purposes, the STAR study was designed. Methods This is a multicentre observational study enrolling patients suffering from an ES refractory to standard treatment from 1 July 2017 to 30 June 2023. The primary outcome was the reduction of treated arrhythmic events by at least 50% comparing the 12 h following PSGB with the 12 h before the procedure. STAR operators were specifically trained to both the anterior anatomical and the lateral ultrasound-guided approach. Results A total of 131 patients from 19 centres were enrolled and underwent 184 PSGBs. Patients were mainly male (83.2%) with a median age of 68 (63.8-69.2) years and a depressed left ventricular ejection fraction (25.0 +/- 12.3%). The primary outcome was reached in 92% of patients, and the median reduction of arrhythmic episodes between 12 h before and after PSGB was 100% (interquartile range -100% to -92.3%). Arrhythmic episodes requiring treatment were significantly reduced comparing 12 h before the first PSGB with 12 h after the last procedure [six (3-15.8) vs. 0 (0-1), P < .0001] and comparing 1 h before with 1 h after each procedure [2 (0-6) vs. 0 (0-0), P < .001]. One major complication occurred (0.5%). Conclusions The findings of this large, prospective, multicentre study provide evidence in favour of the effectiveness and safety of PSGB for the treatment of refractory ES