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Osteoarthritis, one of the most common joint degenerative pathologies, still has no cure, and current treatments, such as nonsteroidal anti-inflammatory drugs, can cause serious adverse effects when taken for a long time. Brown seaweed crude fucoidans are used for the clinical treatment of several pathologies. In this study, the therapeutical potential of these biocompounds was analyzed in primary chondrocytes and the 260TT human chondrocyte cell line. Crude fucoidan from Undaria pinnatifida (Up) and Sargassum muticum (Sm) was obtained by different extraction techniques (microwave-assisted extraction, pressurized hot-water extraction, ultrasound-assisted extraction) and chemically and structurally characterized by Fourier transform infrared spectroscopy, high-performance size-exclusion chromatography, proton nuclear magnetic resonance, and scanning electron microscopy. Once cell viability was confirmed in chondrocytes treated with crude fucoidans, we evaluated their anti-inflammatory effects, observing a significant reduction in IL-6 production stimulated by IL-1β. Findings were confirmed by analysis of IL-6 and IL-8 gene expression, although only fucoidans from Up achieved a statistically significant reduction. Besides this, the antioxidant capacity of crude fucoidans was observed through the upregulation of Nrf-2 levels and the expression of its transcriptional target genes HO-1 and SOD-2, with compounds from Up again showing a more consistent effect. However, no evidence was found that crude fucoidans modulate senescence, as they failed to reduced β-galactosidase activity, cell proliferation, or IL-6 production in chondrocytes stimulated with etoposide. Thus, the findings of this research seem to indicate that the tested crude fucoidans are capable of partially alleviating OA-associated inflammation and oxidative stress, but fail to attenuate chondrocyte senescence. Axencia Galega de Innovación-Xunta de Galicia | Ref. IN607A 2021/7 Xunta de Galicia | Ref. ED481D-2022-018 Ministerio de Ciencia, Innovación y Universidades | Ref. RYC2018-024454-I Xunta de Galicia | Ref. ED431F 2020/01

The leverage of invasive macroalgae, which represent a serious threat for autochthonous biodiversity, may smooth and mitigate their risk from an environmental point of view while providing an economic benefit. This work proposes the suitability of a closed loop biorefinery employing sustainable technologies (namely autohydrolysis, ultrasound assisted extraction, and microwave hydrodiffusion and gravity) for the complete exploitation of the invasive brown macroalgae Sargassum muticum. In particular, sequential extraction methods allowed recovery up to 85% of fucoidan in the form of sulfated fucooligosaccharides in the liquid phase, besides increasing the phloroglucinol and Trolox equivalent antioxidant capacity (TEAC) content up to 9.73 g per 100 g of extract and 31.1 g per 100 g of extract, respectively. Additionally, extract-free Sargassum muticum presented a high enzymatic susceptibility at a high solid loading, implying a production of 15.6 g ethanol per L (91.9% of ethanol yield) in SHF, while the resulting spent solid provided a calorific power of 10.0 MJ kg−1. This work verified the cascade biorefinery employing sustainable technologies as an appropriate strategy for the integral valorization of Sargassum muticum.

Low-cost plant and algal biomass are increasingly demanded as a source of proteins, and also, peptides and amino acids are gaining interest for their biological and functional properties. The reduction in chemicals, time and energy, and the integral valorization of the raw materials in the framework of biorefineries are major concerns in the development of environmentally friendly processes. Subcritical water technology is an efficient green technique useful both for extraction and for hydrolysis of protein and other fractions (lipid, carbohydrates, phenolics). However, adequate selection of operational conditions is needed in order both to maximize their extraction yield and to avoid degradation into monomeric units and decomposition products. This review summarizes the major features of subcritical water–based processes for the extraction/hydrolysis of protein. In order to valorizate other valuable fractions from agro-food wastes and algal biomass, optimal conditions should be established as a compromise solution. Alternatively, stagewise operation to sequentially obtain the target fractions could be desirable.

This study deals with the valorisation of tea leaves from the agricultural pruning remains using clean technologies with low environmental impact. Leaves with null commercial interest were dismissed during the pruning season, however with a sequential combination of microwave hydrodiffusion and gravity (MHG), ultrasound-assisted (US) and pressurized hot water (AH) extractions was possible to recover bioactive compounds. An initial pre-treatment was performed using MHG at selected irradiation powers to facilitate the liberation of antioxidants through the cell membrane. The solid phases were processed by three ways: i) ultrasound bath system (80 °C, 80 KHz, from 15 to 60 min); ii) AH technology (non-isothermal treatment with maximum temperature from 140 to 200 °C); and iii) a sequence of the three aforementioned technologies. Both raw material and liquors were analysed to determine fundamental physicochemical, phytochemical or biological properties. Leaves debris showed positive results in bioactive compounds with a maximum value of total phenolic around 130 mg GAE/g extract in the sequential combination. Antioxidant capacity ranged from 0.3 to 0.9 g Trolox/g extract. The combination of green extraction technologies guarantees an efficient recovery of bioactive compounds, creating the possibility of new products that improve the wellbeing.

This work deals with the study of tea stalks from pruning debris using environmental friendly extraction technology to offer new healthy properties. In the manufacturing tea industry, tea trees require to be pruned every year and most of their remains are discarded as a waste with no economic value. Microwave aqueous extraction and pressurized hot water extraction process (autohydrolysis) were used to recover bioactive compounds from the tea branches. Operating at a fixed solid: liquid ratio (1:15), the effect of the maximum heating temperatures from 140 to 220 °C was studied. Liquid extracts were analysed for total phenolic, oligosaccharides, protein, mineral and heavy metals content, as well as for antioxidant capacity. The antitumoral possibilities were also determined for selected samples. The obtained results indicated that both processes could be used as an alternative to recover bioactive compounds from tea wastes, although microwave-assisted extraction allowed saving time when compared with autohydrolysis processing. The temperature exhibited a relevant effect on the total phenolic content and antioxidant capacity, decreasing with the microwave treatment and increasing with the autohydrolysis temperature. The obtained extracts could be adequate for incorporation in food and non-food fields., Graphical abstract Image 1, Highlights • Tea pruning remains were valorised using green extractions by microwave (MW) and autohydolysis (AH). • MW and AH were efficient technologies to recover bioactive compounds. • Values above 40 mg gallic acid equivalents/g extract and 0.10 g Trolox/g extract were identified. • Future applications in cosmetics, pharmacy or food industries should be explored.

The brown seaweed Sargassum muticum was processed by non isothermal autohydrolysis under conditions selected to maximize fucoidan solubilization (170 °C). Acetone precipitation was tried for recovery of fucose-containing oligosaccharides present in hydrolyzates. The acetone:hydrolyzate volume ratio influenced both yields and composition of the precipitated fractions. The sugar components were mostly found as oligomers, their content increased with acetone:hydrolyzate volume ratio 2.0 (v/v) exhibited slight. The fractions precipitated with 0.1 and 0.9 acetone volumes showed higher phenolic and sulfate content, which was positively correlated with the antiradical activity, and exhibited slightly cytotoxic activity against human colon adenocarcinoma cells. The highest volumes of acetone used led to a slight increase in the apparent viscosity as well as the elastic and viscous moduli of formulated aqueous dispersions of alginate. Steady-state and oscillatory shear measurements of above representative dispersions indicated that the alginate extracted after acetone precipitation exhibited a slight enhancement of the viscoelastic features.

The recovery of biopolymers from natural resources using eco-friendly extraction technologies that enhance their mechanical properties has gained attention in recent years. In this context, this work deals with the isolation of hybrid carrageenans from

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG [Abstract] Synovial fibrosis is a pathological process which contributes to joint pain and stiffness in several musculoskeletal disorders. Fucoidans, sulfated polysaccharides found in brown algae, have recently emerged as promising therapeutic agents. Despite the increasing amount of evidence suggesting the protective role of fucoidans in different experimental approaches of human fibrotic disorders, the effect of these sulfated polysaccharides on synovial fibrosis has not been investigated yet. By an in vitro experimental approach in fibroblast-like synoviocytes, we detected that fucoidans inhibit their differentiation into myofibroblasts with tumor cell-like characteristics and restore apoptosis. Composition and structure of fucoidan appear to be critical for the detected activity. Furthermore, protective effects of these sulfated polysaccharides are mediated by upregulation of nitric oxide production and modulation of TGF-β/smad pathway. Altogether, our results support the use of fucoidans as therapeutic compounds in the treatment of the fibrotic processes involved in rheumatic pathologies. Financial support from the Xunta de Galicia and the European Union (European Regional Development Fund - ERDF) is gratefully acknowledged (Grupos con Potencial de Crecemento 2020, grant number ED431B 2020/55; Centro Singular de Investigación de Galicia 2019–2022, grant number ED431G2019/06; Rede Galega de Terapia Celular 2016, grant number R2016/036). N.F.-F. thanks Xunta de Galicia for her postdoctoral contract [grant number ED481B 2018/071]. M.D.T. thanks Ministry of Economy and Competitiveness of Spain for her postdoctoral grant [grant number RYC2018-024454-I]. C.V.-G. thanks Xunta de Galicia for his postdoctoral contract [grant number ED481D 2017/023]. Authors also thank Universidade da Coruña/CISUG for funding open access charge Xunta de Galicia; ED431B 2020/55 Xunta de Galicia; ED431G 2019/06 Xunta de Galicia; R2016/036 Xunta de Galicia; ED481B 2018/071 Xunta de Galicia; ED481D 2017/023

International audience; Among marine sources, seaweeds and sea anemones are highly attractive for their diversity and complex composition, the major components being polysaccharides, proteins, pigments, phenolic compounds, vitamins and minerals. Seaweeds and sea anemones could be a source of different proteins and peptides with unique structures with interesting biological properties, such as antitumoral, antimicrobial, antiinflammatory, antidiabetic, antioxidant, among others. This chapter presents an overview on the marine algal and anemone bioactive proteins and peptides, their extraction and the development of novel carrier systems with potential interest for pharmaceutical applications.

The waste solids remaining after the ethanolic extraction of arnica were proposed as raw material for the recovery of the remaining phenolic fraction. Greener processes based on intensification extraction, with microwave (MHG) and ultrasound (UAE) assistance and pressurized hot water extraction under subcritical conditions (AH), were studied. The entire process provided approximately 28% of phenolics for the sequence when MHG was used, 22% in the sequence where AH was employed, and the extracts showed up to 60% the ABTS radical scavenging capacity of Trolox. However, the cytotoxic effects on the cell growth of tumoral cells were only moderate. Therefore, considering a possible external topical application, extracts containing selected arnica extracts were further used to develop polymer-based gelled matrices formulated with either chitosan or polyvinyl alcohol. Rheological testing indicated that all proposed matrices exhibited relatively high mechanical features, even better than those determined with matrices prepared with their counterpart commercial arnica tinctures. Overall, the shear-thinning behavior of gelled matrices loaded with arnica extracts obtained by MHG or AH stages was enhanced compared to those containing ethanolic extracts, whereas the viscoelastic features became smoother for polymeric matrices incorporated with arnica extracts recovered at the highest MHG irradiation powers or at the highest set point temperatures of AH treatments. Ministerio de Ciencia, Innovación y Universidades | Ref. RYC2018-024454-I Xunta de Galicia | Ref. ED431F 2020/01 Xunta de Galicia | Ref. ED481B 2018/071

The interest in seaweeds for cosmetic, cosmeceutics, and nutricosmetics is increasing based on the demand for natural ingredients. Seaweeds offer advantages in relation to their renewable character, wide distribution, and the richness and versatility of their valuable bioactive compounds, which can be used as ingredients, as additives, and as active agents in the formulation of skin care products. Bioactive compounds, such as polyphenols, polysaccharides, proteins, peptides, amino acids, lipids, vitamins, and minerals, are responsible for the biological properties associated with seaweeds. Seaweed fractions can also offer technical features, such as thickening, gelling, emulsifying, texturizing, or moistening to develop cohesive matrices. Furthermore, the possibility of valorizing industrial waste streams and algal blooms makes them an attractive, low cost, raw and renewable material. This review presents an updated summary of the activities of different seaweed compounds and fractions based on scientific and patent literature. Ministerio de Ciencia y Tecnología | Ref. RTI2018-096376-B-I00 Xunta de Galicia | Ref. ED431G2019/06

The waste solids remaining after the ethanolic extraction of arnica were proposed as raw material for the recovery of the remaining phenolic fraction. Greener processes based on intensification extraction, with microwave (MHG) and ultrasound (UAE) assistance and pressurized hot water extraction under subcritical conditions (AH), were studied. The entire process provided approximately 28% of phenolics for the sequence when MHG was used, 22% in the sequence where AH was employed, and the extracts showed up to 60% the ABTS radical scavenging capacity of Trolox. However, the cytotoxic effects on the cell growth of tumoral cells were only moderate. Therefore, considering a possible external topical application, extracts containing selected arnica extracts were further used to develop polymer-based gelled matrices formulated with either chitosan or polyvinyl alcohol. Rheological testing indicated that all proposed matrices exhibited relatively high mechanical features, even better than those determined with matrices prepared with their counterpart commercial arnica tinctures. Overall, the shear-thinning behavior of gelled matrices loaded with arnica extracts obtained by MHG or AH stages was enhanced compared to those containing ethanolic extracts, whereas the viscoelastic features became smoother for polymeric matrices incorporated with arnica extracts recovered at the highest MHG irradiation powers or at the highest set point temperatures of AH treatments.

The search of sustainable and environmentally friendly alternatives to obtain compounds for different industrial sectors has grown exponentially. Following the principles of biorefinery and circular bioeconomy, processes in which the use of natural resources such as macroalgae biomass is prioritized are required. This review focuses on a description of the relevance, application and engineering platforms of hydrothermal systems and the operational conditions depending on the target as an innovative technology and bio-based solution for macroalgae fractionation in order to recover profitable products for industries and investors. In this sense, hydrothermal treatments represent a promising alternative for obtaining different high value-added compounds from this biomass; since, the different variations in terms of operating conditions, gives great versatility to this technology compared to other types of processing, allowing it to be adapted depending on the objective, whether it is working under sub/super critical conditions, thus expanding its field of application.

International audience; Microwave hydrothermal processing was employed to obtain valuable gelling or bioactive fractions from U. pinnatifida, assessing the processing conditions following a biorefinery concept. It was identified a relevant impact on the antioxidant properties, sulfate, protein and oligosaccharides content, with the highest values above 200°C, although the maximum in fucose was obtained at 160°C. The lowest temperature involved the highest minerals and sulfate content of the solid phases. Rheology indicated that hydrothermal treatment at 160 °C is adequate to extract alginates with structural and viscoelastic properties similar to those commercially available. The incorporation of the hydrothermal residual solids in the proposed alginate matrices favored the development of systems with potential non-food applications applications. Selected extracts, after an intensification stage using ultrasound, featured interesting biological activities for two human cancer cell lines (A2780; HeLa 229) with percentage of cellular inhibition > 83 and 57%, without positive effects on A549 and HCT-116.

The recovery of bioactive and biopolymer-based compounds from Himantalia elongata brown seaweed was studied using a hydrothermal treatment operating under non-isothermal conditions in a broad temperature range (120–220 °C). Maximum extraction yields were observed at 180 °C, since up to 70.7% dry basis (d.b.) of the initial biomass was solubilized. Initial raw material was chemically characterized. The highest crude fucoidan obtained by hydrothermal extraction was achieved at 160 °C. Maximal sulfate and phlorotannin content in the soluble fraction was obtained under non-isothermal autohydrolysis at 160 °C and at 220 °C, respectively. Both extracts showed cytotoxic effects against lung, ovarian and breast carcinoma cells, achieve the half maximal inhibitory concentration to 1.31 ± 0.98 mg/mL of autohydrolysis extract at 220 °C for ovarian cell line tested. The mildest processing condition with suitable bioactive properties (160 °C) was selected to assess the precipitated alginate features in terms of rheological properties, following a biorefinery approach.

The aqueous extraction of Castanea sativa underutilized parts (leaves, burs, husks) was proposed to obtain different soluble and insoluble fractions. The optimum extraction and concentration conditions were selected based on previously published studies. The extracts from leaves and husks were concentrated by membranes and those from burs were refined by adsorption–desorption to concentrate the active phenolic compounds showing radical scavenging capacity. A preliminary screening was made in order to explore the extracts’ pharmaceutical potential, evaluating the cell viability against representative human tumoral cells and the potential as a cosmetic ingredient was also evaluated for their inhibitory activities against collagenase, elastase and tyrosinase. In addition, chestnut husk ashes were used as an alternative source for potash production suitable to formulate potassium soaps with interesting mechanical properties.

Sargassum muticum is an invasive brown seaweed which could not be eradicated from the Atlantic coasts. Therefore, periodic collection and valorization of its components has been suggested. Efficient multistage and multiproduct processes for the obtaining of valuable fractions from this seaweed, which also could be applicable to other brown seaweeds, were developed. This review discusses the potential of conventional and emerging technologies for the sequential extraction of S. muticum bioactives of interest for food, cosmetic, and pharmaceutical applications.

The effect of different counterions (Na+, K+ and Ca2+) on the sol-gel transition diagrams of kappa/iota-hybrid carrageenan isolated from Gigartina skottsbergii, together with the thermo-rheological features of the obtained gels are presented. Extraction yield (47.8 ± 3.5 g/100 g), molar fractions of kappa (62 ± 2) and iota (38 ± 2) and polymers with molecular masses between 7.5 104 and 7 103 g/mol were also determined for G. skottsbergii extracts. Gels formed in NaCl exhibited stable and weak gel properties. Gels made in KCl and CaCl2 featured stable and intermediate gel characteristics, except those formulated at the largest carrageenan and salt content that can be considered strong. All gels achieved stability after 15 min of maturation. No water syneresis was identified in tested gels. Gel setting and melting temperatures depended on the biopolymer and ionic contents. Gels formed in CaCl2 at the largest biopolymer content and ionic concentration showed thermo-reversible features.

Carrageenan was extracted from Mastocarpus stellatus using hot water extraction under atmospheric and pressurized conditions. The influence of heating temperature during a non-isothermal heating profile up to temperatures in the range 70-190 °C was studied to evaluate the extraction yields and properties of the carrageenan fraction. Under the selected conditions (130 °C), extracted carrageenan (CMs) was used for the green synthesis of gold nanoparticles (AuNPs). After the optimization of the reaction conditions, the synthesized gold nanoparticles (Au@CMs) were characterized by UV-Vis spectroscopy, Z potential measurements, electron microscopy, and X-ray diffraction analysis, which confirmed the formation of spherical, polycrystalline, and negatively charged nanoparticles with a mean diameter of 14.3 ± 2.1 nm. The study conducted by scanning transmission electron microscopy, energy dispersive X-ray analysis and mapping confirmed the presence of carrageenan stabilizing AuNPs. Finally, Fourier transformed infrared spectroscopy was performed to analyze the functional groups of CMs involved in the reduction and stabilization of AuNPs. The selective cytotoxicity and the antioxidant activity of the Au@CMs were evaluated in different cell lines and compared to the CMs. Au@CMs showed an improved antioxidant capacity in cells under oxidative stress and the induction of apoptosis in a monocytic cell line, while no antitumor effect was observed in a lung endothelial cell line.

Marine macroalgae represent an excellent raw material for the production of bioactives, adsorbents, plant biostimulants, soil fertilizers and biogas. The success in the exploitation of seaweeds depends on their characteristics, and the approach used to separate their specific active components. In the context of circular economy, invasive species are a good candidate for exploitation, and biorefinery a key valorization technique. Here we investigate a novel biorefinery scheme for an integral valorization of Sargassum muticum. An initial pressing stage allowed the production of a Sap fraction, which showed potential as a plant biostimulant, increasing both root development and shoot/root ratio, especially when used at a dose of 0.1 g/L lyophilized Sap. The solids after pressing were processed by non isothermal autohydrolysis, using pressurized hot water (up to 120-210 °C), a process previously optimized to solubilize the fucoidan and phlorotannin fractions. The residual solids remaining after pressing and autohydrolysis stages were evaluated for the production of biogas. The obtained value (150 mL CH4/g residual solids at 150 °C) was significantly higher than that found for the raw seaweed. The optimal autohydrolysis temperature (150 °C) is compatible with the production of the fucoidan fraction, although the phenolic content is favoured under more severe operation conditions. We also discuss the possibility of preparing adsorbents for pollutant removal and mineral amendments from the autohydrolysis waste solids. The authors are grateful to the Spanish Ministry of Education and Science (CTM2009-12664) and to Xunta de Galicia (CINBIO Centro singular de investigación de Galicia accreditation 2019-2022) with partial financial support from the European Regional Development Fund – ERDF (Ref. ED431G2019/06). M.D.T. thanks Spanish Ministry of Economy and Competitiveness for her postdoctoral grant (IJCI-2016-27535 and RYC2018-024454-I). N.F.F. thanks CINBIO and Xunta de Galicia for her postdoctoral contract (ED481B 2018/071). MICINN/PN2008-2011/CTM2009-12664

Few medically-approved excipients are available for formulation strategies to endow microcarriers with improved performance in lung drug targeting. Konjac glucomannan (KGM) is a novel, biocompatible material, comprising mannose units potentially inducing macrophage uptake for the treatment of macrophage-mediated diseases. This work investigated spray-dried KGM microparticles as inhalable carriers of model antitubercular drugs, isoniazid (INH) and rifabutin (RFB). The polymer was characterised and different polymer/drug ratios tested in the production of microparticles for which respirability was assessed in vitro. The swelling of KGM microparticles and release of drugs in simulated lung fluid were characterised and the biodegradability in presence of beta-mannosidase, a lung hydrolase, determined. KGM microparticles were drug loaded with 66-91% association efficiency and had aerodynamic diameter around 3 mu m, which enables deep lung penetration. The microparticles swelled upon liquid contact by 40-50% but underwent size reduction (>62% in 90 min) in presence of beta-mannosidase, indicating biodegradability. Finally, drug release was tested showing slower release of RFB compared with INH but complete release of both within 24 h. This work identifies KGM as a biodegradable polymer of natural origin that can be engineered to encapsulate and release drugs in respirable microparticles with physical and chemical macrophage-targeting properties. info:eu-repo/semantics/publishedVersion

Carrageenan and carrageenan oligosaccharides are red seaweed sulfated carbohydrates with well-known antiviral properties, mainly through the blocking of the viral attachment stage. They also exhibit other interesting biological properties and can be used to prepare different drug delivery systems for controlled administration. The most active forms are λ-, ι-, and κ-carrageenans, the degree and sulfation position being determined in their properties. They can be obtained from sustainable worldwide available resources and the influence of manufacturing on composition, structure, and antiviral properties should be considered. This review presents a survey of the antiviral properties of carrageenan in relation to the processing conditions, particularly those assisted by intensification technologies during the extraction stage, and discusses the possibility of further chemical modifications. Xunta de Galicia | Ref. ED431G2019/06 Xunta de Galicia | Ref. ED481B-2018/002 Xunta de Galicia | Ref. ED481B-2018/071 Xunta de Galicia | Ref. ED431F 2020/01 Agencia Estatal de Investigación | Ref. RTI2018-096376-B-I00 Ministerio de Ciencia, Innovación y Universidades (España) | Ref. RYC2018-024454-I

60 p.-4 fig.-6 tab., Fucoidans possess antitumoral properties, confirmed by in vitro and in vivo tests and by some clinical studies. However, the heterogeneous characteristics of these complex polysaccharides, the strong influence of collecting and processing conditions, as well as the lack of assays with standardized purified products make the comparison of available data difficult. Most in vitro tests have been performed with purified fractions, and most in vivo studies with commercial, either crude or purified, fucoidans. Molecular weight, monosaccharide composition, sulfation pattern, and the presence of other substituents are highly dependent on the extraction and purification conditions and in order to maintain active structures, the loss of sulfate and other active groups has to be avoided. This review presents information on the influence of the processing stages on the composition and antitumoral properties of fucoidans, and the relevance of other strategies, such as combination with conventional drugs or encapsulation, to enhance bioactivity., Financial support from the Ministry of Science and Innovation of Spain (CTM2015-68503R), Xunta de Galicia (Centro Singular de Investigación de Galicia, ED431G/02 and Grupos de referencia competitiva ED431C-2016041 and EDC431C 2018/47) and the European Union (European Regional Development Fund - ERDF), is gratefully acknowledged. M.D.T. thank Spanish Ministry of Economy and Competitiveness for her postdoctoral grant (IJCI-2016-27535). N.F.F. and R.S-V thank Xunta de Galicia for their postdoctoral grants (ED481B 2018/073 and ED481D 2017/017).