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46 Páginas ; Background: In addition to the considerable number of different chlorophyll structures originated naturally, prominent research is made to produce new specific semisynthetic structures. The final target is to obtain chlorophyll derivatives with even better bioactive properties than those of the natural parent compounds. Method: A detailed, extensive and critic literature search has been made in Web of Science™. Results: Great efforts are applying to optimize the function of chlorophyll-based photosensitizers, to understand the molecular mechanisms of the antioxidant and antigenotoxic properties of chlorophyll derivatives and, lastly, to investigate new biological actions of them. However, the fundamental physiological functions of the chlorophylls are their physicochemical properties. Conclusion: This review aims to reflect the chemical grounds of the healthy and/or medical features of chlorophylls, including the consequences, advantages or even new actions that modifications over the chlorophyll structure introduce. Finally, new perspectives in the functionality of chlorophylls at molecular level are discussed. ; This work was supported by the Comisión Interministerial de Ciencia y Tecnología (CICYT-EU, Spanish and European Government, AGL 2015-63890-R). ; Peer reviewed

The bioactivity (antioxidant and cytotoxic activities) of the aqueous and methanolic extracts of Arenaria montana L., a plant commonly used in Portuguese folk medicine, was evaluated and compared. Furthermore, the phytochemical composition was determined regarding hydrophilic (sugars, organic acids and phenolic compounds) and lipophilic (fatty acids and tocopherols) compounds, in order to valorize this plant material as a functional food/nutraceutical. Fructose, oxalic acid, methyl-luteolin 2''-O-feruloylhexosyl-C-hexoside, α-tocopherol, and linoleic acid were the main individual compounds found in A. montana. In general, the aqueous extract gave higher antioxidant and cytotoxic activity than the methanolic extract; the latter showed activity only against HeLa and HepG2 cell lines. Both aqueous and methanolic extracts showed some hepatotoxicity but at higher doses than the ones active for tumor cell lines. Moreover, the aqueous extract of A. montana may be used as a functional food or nutraceutical due to the high antioxidant and cytotoxic activity, and to the presence of bioactive compounds. As far as we know, this is the first report on phytochemical composition and bioactivity of A. montana. ; The authors are grateful to Fundação para a Ciência e Tecnologia (FCT, Portugal) for Fnancial support to CIMO (strategic project PEst-OE/AGR/UI0690/2011), REQUIMTE (PEst-C/EQB/ LA0006/2011), M.I. Dias (SFRH/BD/84485/2012 grant), R.C. Calhelha (SFRH/BPD/68344/2010 grant) and L. Barros (contract under "Programa Compromisso com Ciência-2008"). The GIPUSAL is Financially supported by the Spanish Government through the Consolider-Ingenio 2010 Programme (FUN-CFOOD, CSD2007-00063). M. Dueñas thanks to the Programa Ramón y Cajal for a contract.

Three medicinal plants with recognized anti-inflammatory potential, identified as "erva de São João" (Ageratum conyzoides), "Tanchagem" (Plantago major) and " Bardana" (Arctium lappa L.) were obtained from a medicinal herbs company located in Teófilo Otoni city (Minas Gerais State, Brazil). The dry plant material obtained in packages was submitted to the chemical procedures to prepare the crude extracts by maceration according to the Brazilian pharmacopoeia legislation. After extraction, the samples were subjected to 1H NMR, TLC and Capillary Electrophoresis analysis by co-injection of authentic patterns of phenolic acids and flavonoids to identify the major compounds and classes of secondary metabolites present in each material and then their chemical and biological potential was assessed by DPPH free radical inhibition assay and antimicrobial against E. coli. The results obtained allow us to conclude that the phytopreparation was effective in the extraction of compounds with antioxidant potential and the three species presented a high concentration of flavonoids and other phenolics that is compatible with the chemosystematic data. The screening obtained by 1H NMR spectroscopy, TLC and Capillary Electrophoresis with ultraviolet detection analysis provided us a qualitative profile of the phytochemicals present in each material. None of the extracts were active against Escherichia coli by antibacterial disk diffusion assay at concentration of 1 mg/ml.

Demosponges are a well-known source of a plethora of bioactive compounds. In particular, they are able to form a skeleton by direct deposition of silica in a process catalysed by silicatein. Herein, we isolated biosilicas from five different Atlantic deep-sea sponges Geodia atlantica (GA), Geodia barretti (GB), Stelletta normani (SN), Axinella infundibuliformis (AI) and Phakellia ventilabrum (PV) to explore the bioactivity and osteogenic capacity of its silica-based materials. We chemically characterized the isolated biosilicas and evaluated them for their bioactivity to deposit Ca and P on their surface (by immersion in simulated body fluid, SBF). GB-, SN-, AI- and PV-based biosilicas did not generate a stable calcium phosphate (CaP) layer over time in the presence of SBF, however, the GA-derived one was able to form a CaP surface layer (at a Ca/P ratio of ~1.7, similar to the one observed for hydroxyapatite), that was stable during the 28 days of testing. In addition, no cytotoxicity towards L929 and SaOs2 cells was observed for the GA-based biosilica up to a concentration of 10 mg/mL. Overall, the GA-based biosilica presents the characteristics to be used in the development of biomaterials for bone tissue engineering (BTE). ; This research has been performed with funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreements No. 679849 (SponGES) and No. 668983 (FORECAST). Funding from the European Regional Development Fund, through Atlantic Area Program, under the scope of BlueHuman project (EAPA_151/2016) is also acknowledged. JRX research was also supported by National Funds through FCT, the Portuguese Foundation for Science and Technology within the scope of UIDB/04423/2020, UIDP/04423/2020, and ...

Abstract
Extensive efforts are underway to develop bacteriophages as therapies against antibiotic-resistant bacteria. However, these efforts are confounded by the instability of phage preparations and a lack of suitable tools to assess active phage concentrations over time. In this study, we use dynamic light scattering (DLS) to measure changes in phage physical state in response to environmental factors and time, finding that phages tend to decay and form aggregates and that the degree of aggregation can be used to predict phage bioactivity. We then use DLS to optimize phage storage conditions for phages from human clinical trials, predict bioactivity in 50-y-old archival stocks, and evaluate phage samples for use in a phage therapy/wound infection model. We also provide a web application (Phage-Estimator of Lytic Function) to facilitate DLS studies of phages. We conclude that DLS provides a rapid, convenient, and nondestructive tool for quality control of phage preparations in academic and commercial settings.

We report on the growth of non-stoichiometric nanocrystalline hydroxyapatite (nHAp) with a composition similar to natural bone by a wet-chemical in-situ precipitation route on carbon nanotubes (CNTs) with different degrees of oxygen functionalities and on graphene oxide (GO). Both, functionalization degree and morphology of CNTs and GO appear as critical parameters controlling the shape and crystallinity of the self-assembled nHAp nanoparticles in the corresponding composite materials. Crystalline nHAp nanoparticles with rod-like morphology were achieved for moderately oxidized CNTs and for GO. On CNTs these grow along the CNT's axis while on GO they form a compact layer. In both cases enhanced nHAp integration onto the respective carbon support is obtained. In vitro bioactivity of the prepared composites exhibits a fast apatite biomineralization process, induced by the presence of nHAp. Depending on its crystalline size and dispersion degree remineralization of the apatite nanoparticles takes place through the inclusion of PO4 3 and CO32 by ion exchange. Importantly, during the stage of bioactivity the integration degree of nHAp nanoparticles on the carbon nanostructures alters with time, evidencing the potential of GO as valuable bioceramic support material. ; Spanish Ministry MINECO (project MAT201015026 ; Spanish National Research Council CSIC (project 201080E124, and PhD grant JAEPre09-01155) ; Regional Government of Aragon and the European Social Fund (DGA-ESF-T66 Grupo Consolidado) ; EU COST network MP0901 NanoTP ; EU 7th Framework Program (Grant Agreement 312483-ESTEEM2) ; Peer reviewed

The antioxidant activity of baked foods is of utmost interest when envisioning enhancing their health benefits. Incorporating functional ingredients is challenging since their bioactivity naturally declines during baking. In this study, 3D food printing and design of experiments are employed to clarify how the antioxidant activity of cookies enriched with encapsulated polyphenols can be maximized. A synergistic effect between encapsulation, time, temperature, number of layers, and infill of the printed cookies was observed on the moisture and antioxidant activity. Four-layer cookies with 30% infill provided the highest bioactivity and phenolic content if baked for 10 min and at 180 °C. The bioacitivity and total phenolic content improved by 115% and 173%, respectively, comparing to free extract cookies.Moreover, the proper combination of the design and baking variables allowed to vary the bioactivity of cooked cookies (moisture 35%) between 300 and 700 ?molTR/gdry. The additive manufacture of foods with interconnected pores could accelerate baking and browning, or reduce thermal degradation. This represents a potential approach to enhance the functional and healthy properties of cookies or other thermal treated bioactive food products. ; The research leading to these results has received funding from FODIAC – Food for Diabetes and Cognition, funded by European Union, under the call Marie Skłodowsk-Curie Research and Innovation Staff Exchange (Ref. H2020-MSCA-RISE-778388); PhD grantship from Fondazione di Piacenza e Vigevano (Doctoral School on the Agro-Food System, Università Cattolica del Sacro Cuore); Fondazione Cariplo through the project ReMarcForFood – Biotechnological strategies for the conversion of Winemaking by-products and their recycling into the food chain: development of new concepts of use, 2016-0740 grant. ...

Ethanol and organic acid extracts from the leaves of Vitex madiensis Oliv. were evaluated for their antihelminthic activity using the animal model of Benhamia rosea and B. itoleisis (Kinshasa/DRC earthworms), antibacterial activity and antioxidant activity. Different concentrations (5 mg/mL, 2.5 mg/mL, 1.25 mg/mL and 0.625 mg/mL) of standard Albendazole (positive control) and sample solutions (organic acid extracts and ethanol extracts) were used for this study which involved the determination of the paralysis time (vermifuge) and mortality time (vermicidal activity) of the worms. The presence of different secondary metabolites was determined by the thin layer chromatography. The results obtained showed that the ethanolic extract and the organic acid extracts showed significant antihelminthic activity. Microscopic examination of the parts used revealed the presence of various histological elements. Its phytochemical profile remains dominated by various secondary metabolites such as coumarins, anthraquinones, flavonoids, phenolic acids and terpenoids. The mineral composition was determined by inductively coupled argon plasma optical emission spectrometry (ICP-EOS) showed the abundance of various elements, namely calcium, iron, potassium, selenium, sodium, magnesium, manganese, nickel, phosphorus, cobalt, copper, barium and zinc in this plant. The antibacterial activity of the extracts of this plant was weak against the bacterial strains tested. The organic acid and ethanol extracts showed interesting antioxidant activity. The leaves extracts of Vitex madiensis Oliv. showed good antihelminthic, antibacterial and antioxidant activities related to their phytochemical compositions. All these results constitute scientific evidence validating the use of this medicinal plant for the management of parasitic infections of small ruminants in the Democratic Republic of the Congo.

Uncaria acida (red bajakah) and Uncaria glabrata (white bajakah) belong to the liana woody species. Both are naturally cultivated in Indonesia, particularly in Kalimantan (Borneo) island. This study, aims to investigate the extractive composition of U. acida and U. glabrata wood considering that extracts from different lianas usually are used as anticancer drugs (breast cancer). The phenolic, alkaloid, and saponin contents were measured by colorimetric and GC-MS methods, while the antioxidant, antifungal, and cytotoxicity were investigated using DPPH, Phanerochaete chrysosporium (white-rot), and brine shrimp lethality tests, respectively. The results showed that the total tannins, phenols, and saponins in U. acida were higher compared to U. glabrata, while the total flavonoids, alkaloids, polysaccharides, and antioxidant activity was lower. The GC-MS analysis indicated the presence of aromatic compounds, fatty acids, and triterpenoids in both species. High concentration of phenols, alkaloids, saponins, fatty acids, and steroids are known to provide support in terms of antioxidant, cytotoxicity, and antifungal activities.