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•The role of compressed fluids-based extraction techniques for the recovery of valuable products from natural sources is discussed.•Current state is presented considering the needs ...identified 3 years ago.•Biorefinery platforms based on supercritical and/or pressurized fluids are highlighted.
The role of compressed fluids-based extraction techniques for the sustainable recovery of valuable products from natural sources is described and discussed. Important aspects for green process design including the use of new solvents with novel properties, the development of integrated and intensified multi-unit operation processes as well as scale-up and techno-economic and environmental assessment are emphasized. Within this important research field, some key aspects are identified for the future development of more efficient, environmentally friendly and sustainable processes for bioactives recovery from natural sources. The use of biorefinery platforms based on the use of supercritical and/or pressurized fluids will have a critical importance in the near future.
Recently, the high analytical power provided by the new HRMS instruments (working in the MS or MS/MS mode, stand alone or hyphenated with separation techniques) is making more feasible the ...characterization of plant secondary metabolites. In this regard, HRMS-based techniques are becoming the technique of choice, since they are capable of answering many questions regarding the analytical characterization of secondary metabolites, usually found in very complex matrices, including their structural elucidation and quantification in a very fast and sensitive way. In this manuscript we will provide a critical and updated revision of this topic covering the works published in the last 4 years (2015–2018), including the different configurations in which HRMS may be used (stand alone or hyphenated), the data treatment, the strategies for the identification of unknown metabolites, the current software for structure elucidation, as well as the last trends and future outlooks in this hot area of research.
•Recent HRMS-based applications for plant secondary metabolites are reviewed.•Stand alone or hyphenated HRMS configurations are discussed and compared.•A broad variety of databases and HRMS-data mining strategies are presented.•Future challenges in dereplication and metabolite profiling are emphasized.
Arecaceae palm tree fruits (APTFs) with pulp or kernel rich in oil are widely distributed in six Brazilian biomes. APTFs represent a great potential for the sustainable exploitation of products with ...high added value, but few literature studies have reported their properties and industrial applications. The lack of information leads to underutilization, low consumption, commercialization, and processing of these fruit species. This review presents and discusses the occurrence of 13 APTFs and the composition, physicochemical properties, bioactive compounds, and potential applications of their 25 oils and fats. The reported studies showed that the species present different lipid profiles. Multivariate analysis based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) indicated a correlation between the composition of pulp and kernel oils. Myristic, caprylic, capric, and lauric acids are the main saturated fatty acids, while oleic acid is the main unsaturated. Carotenoids and phenolic compounds are the main bioactive compounds in APTFs, contributing to their high oxidative stability. The APTFs oils have a potential for use as foods and ingredients in the cosmetic, pharmaceutical, and biofuel industries. However, more studies are still necessary to better understand and exploit these species.
•In-depth response surface analysis was done for scCO2 extraction of H. pluvialis.•Ethanol cosolvent affected extract’ antioxidant activity more than pressure or temperature.•We investigated a ...further increase in ethanol up to the region of gas-expanded liquids.•Astaxanthin recovery was larger in CO2-expanded ethanol (CXE) than scCO2 extractions.•CXE extracts high-value compounds from microalgae to unprecedented levels.
Microalgae represent diverse branch of microorganism that can produce a wide range of unique functional ingredients that can be used in food, cosmetics, pharmaceuticals, and energy. Among them, Haematococcus pluvialis is known for accumulating the highest levels of a potent natural antioxidant, astaxanthin, which has demonstrated positive health effects. Therefore, the aim of numerous studies has been to develop novel and efficient extraction techniques to produce high-quality (purity and antioxidant activity) extracts, while complying with the Green Chemistry Principles. Supercritical CO2 (scCO2) emerges as an alternative to organic solvents because of its high selectivity and bioactivity-preserving qualities. Nevertheless, astaxanthin is a large molecule with low solubility in scCO2 that usually requires long extractions at high pressures. Ethanol has been used as co-solvent to increase astaxanthin solubility in scCO2. In this work, a Box–Behnken experimental design was used to study the effects of operating pressure (20–35MPa), temperature (40–70°C), and ethanol content in scCO2 (0–13%, w/w) on the yield, astaxanthin content, and antioxidant activity of H. pluvialis extract. Results showed that ethanol content in CO2 has a more significant effect on all responses than pressure and temperature. These results lead us to investigate the effect of a further increase in ethanol content, up to the region of gas-expanded liquids. We studied the effects of temperature (30–60°C) and ethanol content (50–70%, w/w) at a fixed pressure (7MPa) on the same response variables using CO2-expanded ethanol (CXE). Results showed that temperature and ethanol content had a significant influence on astaxanthin yield and antioxidant activity. Also, the overall responses of CXE surpassed scCO2 extractions to match conventional extraction with acetone, maintaining high quality extracts, thus validating the use of this new type of green technology for extraction of high-value compounds.
The consumption of dietary fats have been long associated to chronic diseases such as obesity, diabetes, cancer, arthritis, asthma, and cardiovascular disease; although some controversy still exists ...in the role of dietary fats in human health, certain fats have demonstrated their positive effect in the modulation of abnormal fatty acid and eicosanoid metabolism, both of them associated to chronic diseases. Among the different fats, some fatty acids can be used as functional ingredients such as alpha-linolenic acid (ALA), arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), γ-linolenic acid (GLA), stearidonic acid (STA) and conjugated linoleic acid (CLA), among others. The present review is focused on recent developments in FAs analysis, covering sample preparation methods such as extraction, fractionation and derivatization as well as new advances in chromatographic methods such as GC and HPLC. Special attention is paid to
trans fatty acids due its increasing interest for the food industry.
With the progressive aging of the population, bone fractures are an increasing major health concern. Diverse strategies are being studied to reduce the recovery times using nonaggressive treatments. ...Electrical stimulation (either endogenous or externally applied electric pulses) has been found to be effective in accelerating bone cell proliferation and differentiation. However, the direct insertion of electrodes into tissues can cause undesirable inflammation or infection reactions. As an alternative, magnetoelectric heterostructures (wherein magnetic fields are applied to induce electric polarization) could be used to achieve electric stimulation without the need for implanted electrodes. Here, we develop a magnetoelectric platform based on flexible kapton/FeGa/P(VDF-TrFE) (flexible substrate/magnetostrictive layer/ferroelectric layer) heterostructures for remote magnetic-field-induced electric field stimulation of human osteoblast cells. We show that the use of flexible supports overcomes the clamping effects that typically occur when analogous magnetoelectric structures are grown onto rigid substrates (which preclude strain transfer from the magnetostrictive to the ferroelectric layers). The study of the diverse proliferation and differentiation markers evidence that in all the stages of bone formation (cell proliferation, extracellular matrix maturation, and mineralization), the electrical stimulation of the cells results in a remarkably better performance. The results pave the way for novel strategies for remote cell stimulation based on flexible platforms not only in bone regeneration but also in many other applications where electrical cell stimulation may be beneficial (e.g., neurological diseases or skin regeneration).
► Compressed fluids show important advantages for extraction of bioactives. ► SFE, PLE and SWE are fast, reliable and clean methods for extracting bioactives. ► Principles, instrumentation and ...applications of SFE, PLE and SWE are presented.
The improvement of sample-preparation and extraction techniques for determinations of natural bioactive compounds is very important. New concepts relate to not only enhancement of extraction efficiencies but also environmental impact. This evolution towards Green Analytical Chemistry is to new extraction and sample-preparation processes that should be faster, more reproducible and more environmentally friendly.
Compressed fluid-based sample-preparation techniques (e.g., supercritical fluid extraction and pressurized liquid extraction) demonstrate good capabilities. In this review, we update knowledge on the techniques together with the main technical developments and the most notable recent applications for the extraction of bioactive compounds.
A green cascade approach was used to recover phycocyanins, carotenoids and lipids from Galdiera phlegrea. Phycocyanin extraction was performed by high pressure homogenization and purified by ...ultrafiltration, whereas carotenoids were obtained by a pressurized liquid extraction and lipids by supercritical fluid extraction. The second step of this innovative, green, and cost-effective procedure is able to improve the recovery of zeaxanthin and β-carotene up to 40%, without affecting the quality of compounds and avoiding the use of organic solvents and the drying processes. The isolated carotenoids were active as antioxidants, as clearly shown by their protective activity on a cell-based model. The lipid yield was increased by 12% with respect to conventional methods.
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