Adsorpcijske izoterme i kinetičko modeliranje uklanjanja fenolnih spojeva pomoću aktivnog ugljena, iz otpadnih voda dobivenih pri proizvodnji maslinovog ulja

The adsorption of phenolic compounds from olive oil wastewater by commercial activated carbon was studied as a function of adsorbent quantity and temperature. The sorption kinetics and the equilibrium isotherms were evaluated. Under optimum conditions (8 g of activated carbon per 100 mL), the maximum sorption capacity of activated carbon expressed as mg of caff eic acid equivalent per g of activated carbon was 35.8 at 10 °C, 35.4 at 25 °C and 36.1 at 40 °C. The pseudo-second-order model was considered as the most suitable for kinetic results, and Langmuir isotherm was chosen to bett er describe the sorption system. The results confi rmed the effi ciency of activated carbon to remove almost all phenolic compound fractions from olive mill effl uent. The preliminary results obtained will be used in future studies. The carbohydrate fraction of this upgraded residue could be employed to produce bioethanol, and adsorbed phenolic compounds can be recovered and used in different industries.U radu je ispitana ovisnost adsorpcije fenolnih spojeva iz otpadnih voda, dobivenih pri proizvodnji maslinovog ulja, o količini adsorbensa (komercijalni aktivni ugljen) i temperaturi. Proučene su kinetika sorpcije i ravnotežne izoterme. Pri optimalnim uvjetima (8 g aktivnog ugljena na 100 mL) najveća je sposobnost sorpcije, izražena u mg ekvivalenata kafeinske kiseline po g aktivnog ugljena, iznosila 35,8 pri temperaturi od 10 °C, 35,4 pri 25 °C i 36,1 pri 40 °C. Dobivene kinetičke rezultate najbolje je opisao model pseudo drugog reda, dok je za opisivanje sorpcije odabrana Langmuirova izoterma. Rezultati potvrđuju učinkovitost aktivnog ugljena u uklanjanju gotovo svih fenolnih spojeva iz otpadnih voda. Ovi će se preliminarni rezultati upotrijebiti u daljnjim istraživanjima. Ugljikohidrati preostali nakon uklanjanja fenolnih spojeva iz otpadnih voda mogli bi se upotrijebiti za dobivanje bioetanola, a adsorbirani se fenolni spojevi mogu naknadno koristiti u raznim granama industrije

Optimization of PCL Polymeric Films as Potential Matrices for the Loading of Alpha-Tocopherol by a Combination of Innovative Green Processes

Active food packaging represents an innovative way to conceive food packages. The innovation lies in using natural-based and biodegradable materials to produce a system intended to interact with the food product to preserve its quality and shelf-life. Compared to traditional plastics, active packaging is designed and regulated to release substances in a controlled manner, mainly antimicrobial and antioxidant compounds. Conventional technologies are not suitable for treating these natural substances; therefore, the research for innovative and green techniques represents a challenge in this field. The aim of this work is to compare two different polymeric structures: nanofibrous films obtained by electrospinning and continuous films obtained by solvent casting, to identify the best solution and process conditions for subjecting the samples to the supercritical fluids impregnation process (SFI). The supports optimized were functionalized by impregnating alpha-tocopherol using the SFI process. In particular, the different morphologies of the samples both before and after the supercritical impregnation process were initially studied, identifying the limits and possible solutions to obtain an optimization of the constructs to be impregnated with this innovative green technology in the packaging field

Small diameter vascular grafts coated with gelatin

In the field of tissue engineering, there is an increased demand for small diameter vascular grafts to treat peripheral vascular pathologies and ischemic heart diseases. The limited availability of suitable autogenous veins and the drawbacks related to the use of synthetic materials, such as polyethylene terephthalate (Dacron\uc2\uae) and expanded polytetrafluoroethylene (ePTFE), especially when they are used as substitutes for small diameter vessels, have attracted several investigators turning their attention toward the fabrication of alternative biocompatible grafts. In this study, small diameter tubular grafts (2 mm), made of poly (\ucf\ub5-caprolactone) (PCL) and poly (glycerol sebacate) (PGS) at a ratio of 1:1 (v/v) were obtained by electrospinning. With the aim to reduce water permeability, their surface was modified by dynamic coating of gelatin at 37 \uc2\ub0C for 1 h, followed by UV-irradiation. Thickness, fiber diameters, porosity, mass loss, fluid uptake, water permeability, gelatin release, mechanical properties, cytotoxicity, and hemocompatibility of gelatin-coated electrospun scaffolds (GCS) were studied and compared with uncoated scaffolds (UCS). Scanning electron microscopy (SEM) images showed that the gelatin surface modification did not affect the 3D structure and pore interconnectivity of the scaffolds. A significant decrease in the water permeability was noticed when gelatin was used as coating agent. The results of this study highlighted the importance of a very low cost surface treatment with gelatin to improve the properties of PCL:PGS electrospun grafts. In conclusion, these gelatin-coated prostheses could be considered as a good candidate for vascular replacement in tissue engineering

Grape by-products: extraction of polyphenolic compounds using supercritical CO2 and liquid organic solvent - a preliminary investigation.

This research focussed on the exploitation of grape by-products as a source of polyphenolic compounds, which are of interest to the food, pharmaceutical and cosmetic industries. In particular, two substrates were tested: Pinot Noir grape skins and grape seeds. Pinot Noir grape skins were extracted by supercritical CO2 added with ethanol as modifier at constant temperature (45 °C) and at variable pressure (200, 300, 400 or 500 bar). The supercritical extraction kinetics of polyphenolic compounds was obtained. Grape seeds were extracted by combining supercritical (at 40 °C and 500 bar and using CO2 or CO2 added with ethanol as modifier) with liquid ethanol extraction. The supercritical technique seemed not to be really effective in extracting polyphenolic compounds; it can be anyway utilized to selectively extract grape seed oil by avoiding any solvent contamination of the matrix which can be further extracted for the recovery of polyphenolic compounds by means of liquid organic solvent

Microalgae growth using winery wastewater for energetic and environmental purposes

Winery wastewater (WWW), produced by winemaking activities (cleaning, transferring and storage operations), is an aqueous solution containing ethanol, organic acids, sugars, aldehydes, other microbial metabolites, soaps and detergents. Nowadays, innovative wastewater treatment processes are based on bacterial and yeast species while the role of microalgae is still unclear. Arthrospira (Spirulina) platensis and Chlorella vulgaris are unicellular prokaryotic and eukaryotic microorganisms, respectively, which can be easily grown even in non-optimal conditions. Several studies reported that the amount and quality of lipids contained in microalgal cells can differ as an outcome of changes in growth conditions or growth medium characteristics (concentration of carbon, nitrogen, phosphate, iron, etc.). In this study, we investigated the influence of different concentrations of WWW (20, 40 and 60 % v/v of the medium) on the growth and chemical composition of those photosynthetic microorganisms. Microalgae were grown into vertical glass bubblers (250 mL). The biomass concentration was quantified daily by measuring the optical density at 560 and 625 nm for A. platensis and C. vulgaris, respectively. Total Carbon and total Nitrogen concentrations, both in the media (mg/L) and in microalga biomass (g/100g), were monitored by a CHNS-O analyser. In order to quantify the influence of WWW-enrich media on the lipid concentration and composition, biomass was collected at the beginning of the stationary phase and the lipid fraction was extracted. Results suggested that the two tested microalgae can growth in media enriched with WWW and the total Nitrogen concentrations decreased up to 90 and 100 % for A. platensis and C. vulgaris, respectively. In conclusion, WWW could be successfully used for the growth of the tested microalgae, leading to a reduction of the environmental impact of this wastewater

Zein and Spent Coffee Grounds Extract as a Green Combination for Sustainable Food Active Packaging Production: An Investigation on the Effects of the Production Processes

In this work, the effect of different production techniques was evaluated on the physical and antioxidant properties of bio-based packaging intended to prevent the premature oxidation of packaged foods. Spent coffee ground extract, rich in antioxidant molecules, obtained through high pressure and temperature extraction, was loaded on zein polymeric matrices. The techniques adopted in this work are particularly suitable due to their mild conditions to produce active packaging completely based on natural compounds: electrospinning, solvent casting, and spin coating. The novelty of this work lay in the investigation of the dependance of the properties of active packaging on the adopted production techniques; the results clearly indicated a strong dependence of the features of the films obtained by different production processes. Indeed, spin coated samples exhibited the best oxygen barrier properties, while a higher tensile strength was obtained for the casted samples, and the fastest release of active compounds was provided by electrospun mats. The films produced with different methods had different physical properties and the release of extract bioactive compounds can be tunable by varying the production technique, dependent on the variable to be considered. The products developed offer an alternative to traditional packaging solutions, being more eco-sustainable and promoting waste valorization

Texture profile and sensory acceptance of a symbiotic diet aerated mousse containing Lactobacillus acidophilus LA-5, inulin, and fructooligosaccharide

This work dealt with the texture profile and sensory acceptance of a symbiotic diet aerated mousse containing Lactobacillus acidophilus LA-5, inulin, and fructooligosaccharid

The Effect of Tag Positioning on Passive Radio Frequency Identification (RFID) Performance: Case of Food Beverages

Smart packaging containing sensors could be considered the natural progression in packaging innovation for many consumer products. The goal of implementing sensors into the packaging is to improve product traceability and sustainability and to increase product shelf-life. Radio-frequency identification (RFID) systems have already been adopted for traceability purposes in many supply chains including apparel, electronics, pharmaceuticals, and food. The Ultra-High Frequency (UHF) range is widely used for those purposes. However, to improve the adoption of this technology several challenges need to be overcome. The goal of this research was to determine the best configuration for attaching a passive UHF RFID tag to different beverage bottles. To do this, three different packaging materials (polyethylene terephthalate (PET), clear glass, and Tetrapak®) which are commonly used in the beverage industries, and three commercially available passive UHF RFID tags with different designs were used. The influence of the RFID positioning (bottom or top) on the performance of tags using empty and water-filled bottles was assessed. Power on tag Forward and Theoretical Read Range were used as the indicators of the tag performance. The results of this study confirmed that tag positioning affects the performance of the RFID system. In order to have the best passive UHF RFID tag performance, packaging and labeling industries should consider the effect of tag design, packaging material, and food composition

Selection of Co-Substrate and Aeration Conditions for Vanillin Production by Escherichia coli JM109/pBB1

Yeast extract, Luria-Bertani medium and tryptone were tested as co-substrates for vanillin production from ferulic acid by resting cells of Escherichia coli JM109/pBB1. Yeast extract proved to be the best component for sustaining such a bioconversion, which is not self-sustained from the bioenergetic point of view. Tests were also performed under variable aeration conditions by simultaneously varying the ratio of medium to vessel volume and the agitation speed. The results of these tests suggest that, under excess aeration, a non-specific oxidase activity was very likely responsible for the oxidation of a significant portion of vanillin to vanillic acid, thus reducing the vanillin yield

A Biorefinery from Spent Coffee Grounds: from High-added Value Compounds to Energy by Innovative Processes

Turning waste into a resource is one of the main aims in circular economy systems. The European Union is strongly promoting innovation in recycling and reuse to reduce waste generation and encouraging the transformation of waste into a major, reliable source of raw materials, to recover energy only from non-recyclable materials, and virtually to eliminate landfilling. In this work, Coffea canephora spent coffee grounds were proposed as raw material for a biorefinery involving green processes and innovative solvents, and the effect of pre-treatments on materials destined to energy production was evaluated