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Dandelion is a sustainable biomass that has occasional use in the food and pharmaceutical industry. However, commercial use of its extracts is restricted by the lack of systematic information on safety, composition, and biological activity. To broaden dandelion use, the present study brings new knowledge on extracts from dandelion seeds that could find application as safe and functional food ingredients. The employed two-step supercritical fluid extraction process, followed by the conventional extraction, enabled the separation of extracts with increased content of phenolics, tocopherols, and essential fatty acids. Those compounds were found to be the major components of dandelion extracts, reaching high values up to 799 mg GE/g, 249 mg α-TE/g, and 75%, respectively. The extracts also contained significant amounts of flavonoids (up to 20.5 mg QE/g) and pigments (chlorophyll A up to 1.0 g/kg, chlorophyll B up to 0.3 g/kg, and carotenoids up to 0.1 g/kg). This study revealed new bioproducts that express strong antioxidant (reaching IC50 values up to 132.5 μg/mL) and antimicrobial activity (with minimum inhibitory concentrations up to 80.0 μg/mL). Among the tested 23 microbial strains, the extracts exhibited the strongest activity against food-borne pathogens Micrococcus luteus and Bacillus subtilis. Furthermore, the antitumor and antiviral activity of separated dandelion biological products was evaluated. [ABSTRACT FROM AUTHOR]

This review provides a concise overview of up-to-date developments in the processing of neat poly(lactic acid) (PLA), improvement in its properties, and preparation of advanced materials using a green medium (CO2 under elevated pressure). Pressurized CO2 in the dense and supercritical state is a superior alternative medium to organic solvents, as it is easily available, fully recyclable, has easily tunable properties, and can be completely removed from the final material without post-processing steps. This review summarizes the state of the art on PLA drying, impregnation, foaming, and particle generation by the employment of dense and supercritical CO2 for the development of new materials. An analysis of the effect of processing methods on the final material properties was focused on neat PLA and PLA with an addition of natural bioactive components. It was demonstrated that CO2-assisted processes enable the control of PLA properties, reduce operating times, and require less energy compared to conventional ones. The described environmentally friendly processing techniques and the versatility of PLA were employed for the preparation of foams, aerogels, scaffolds, microparticles, and nanoparticles, as well as bioactive materials. These PLA-based materials can find application in tissue engineering, drug delivery, active food packaging, compostable packaging, wastewater treatment, or thermal insulation, among others. [ABSTRACT FROM AUTHOR]

Chitosan/gelatin and chitosan/gelatin/zeolite films prepared by solvent casting method are impregnated with a mixture of thymol and carvacrol using a green solvent, supercritical carbon dioxide at 35 °C and 30 MPa, during 18 h. Proposed method enables preparation of biocompatible and biodegradable blends with strong antioxidant and antibacterial activity, whereby amounts of loaded thymol/carvacrol (TC) mixture are in the range from 3.3% to 6%. After initial burst release, both types of films exhibit gradual release of bioactive compounds, with around 72% and 96% of impregnated TC mixture released in water and phosphate buffered saline solution (pH 7.4) during tested period of 10 days, respectively. Results of water vapor transmission rate (>76 g m−2 day−1) confirm that prepared composites are suitable for wound dressing application. Thermal analysis shows superior properties of prepared TC loaded films compared to control samples. In addition, mechanical and structural properties, as well as solubility and swelling behavior of the obtained films are investigated in detail. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) stands out as the most promising biodegradable alternative to conventional petrochemical‐based polymers for manufacturing of high‐performance materials applied in medicine, pharmacy, food, textile, and electronic industry. This review was aimed to present the conventional and up‐to‐date technologies for PLA processing including melt blending and molding, hot melt extrusion, 3D printing, foaming, impregnation, thermally induced phase separation, nano‐ and microparticles preparation, wet and dry spinning processes. In addition, the effect of the processing parameters and polymer characteristics on the properties of the final material was elaborated. Diverse possibilities to tailor properties of PLA‐based materials by variation in polymer characteristics and concentration, solvent selection, drying method, processing pressure and temperature, incorporation of bioactive components, and so on were highlighted. The examples of the relations between processing methods, parameters, and end‐product properties are given for a better understanding of all aspects that need to be perceived for fabrication of PLA‐based materials with required performances. [ABSTRACT FROM AUTHOR]