RESUMO
A risk assessment on the aquatic toxicity of the plant biostimulant strigolactone mimic (2-(4-methyl-5-oxo-2,5-dihydro-furan-2-yloxy)-benzo[de]isoquinoline-1,3-dione (SL-6) was performed using a suite of standardised bioassays representing different trophic groups and acute and chronic endpoints. In freshwater, three trophic groups of algae, crustacea and fish were used. Whilst in seawater, algae (unicellular and macroalgae), Crustacea and Mollusca were employed. In addition, the genotoxicity of SL-6 was determined with the comet assessment performed on unicellular marine algae, oysters, and fish embryos. This was the first time ecotoxicity tests have been performed on SL-6. In freshwater, the lowest LOEC was measured in the unicellular algae at 0.31â¯mg/L SL-6. Although, similar LOEC values were found for embryo malformations and impacts on hatching rate in zebrafish (LOEC 0.31-0.33â¯mg/L). Consistent malformations of pericardial and yolk sac oedemas were identified in the zebrafish embryos at 0.31â¯mg/L. In marine species, the lowest LOEC was found for both Tisbe battagliai mortality and microalgae growth at an SL-6 concentration of 1.0â¯mg/L. Significant genotoxicity was observed above control levels at 0.0031â¯mg/L SL-6 in the unicellular algae and 0.001â¯mg/L SL-6 in the oyster and zebrafish larvae. When applying the simple risk assessment, based on the lowest NOECs and appropriate assessment factors, the calculated predicted no effect concentration (PNEC), for the ecotoxicity and the genotoxicity tests were 1.0⯵g/L and 0.01⯵g/L respectively.
Assuntos
Compostos Heterocíclicos com 3 Anéis , Lactonas , Poluentes Químicos da Água , Peixe-Zebra , Animais , Larva , Crustáceos , Testes de Mutagenicidade , Poluentes Químicos da Água/toxicidadeRESUMO
Strigolactones (SLs) have potential to be used in sustainable agriculture to mitigate various stresses that plants have to deal with. The natural SLs, as well as the synthetic analogs, are difficult to obtain in sufficient amounts for practical applications. At the same time, fluorescent SLs would be useful for the mechanistic understanding of their effects based on bio-imaging or spectroscopic techniques. In this study, new fluorescent SL mimics containing a substituted 1,8-naphthalimide ring system connected through an ether link to a bioactive furan-2-one moiety were prepared. The structural, spectroscopic, and biological activity of the new SL mimics on phytopathogens were investigated and compared with previously synthetized fluorescent SL mimics. The chemical group at the C-6 position of the naphthalimide ring influences the fluorescence parameters. All SL mimics showed effects similar to GR24 on phytopathogens, indicating their suitability for practical applications. The pattern of the biological activity depended on the fungal species, SL mimic and concentration, and hyphal order. This dependence is probably related to the specificity of each fungal receptor-SL mimic interaction, which will have to be analyzed in-depth. Based on the biological properties and spectroscopic particularities, one SL mimic could be a good candidate for microscopic and spectroscopic investigations.
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Lactonas , Naftalimidas , Naftalimidas/química , Naftalimidas/síntese química , Naftalimidas/farmacologia , Lactonas/química , Lactonas/farmacologia , Lactonas/síntese química , Estrutura Molecular , Ascomicetos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Rhizoctonia/efeitos dos fármacos , Compostos Heterocíclicos com 3 AnéisRESUMO
DNA repair plays an essential role in maintaining genomic stability, and can be assessed by various comet assay-based approaches, including the cellular repair assay and the in vitro repair assay. In the cellular repair assay, cells are challenged with a DNA-damaging compound and DNA damage removal over time is assessed. In the in vitro repair assay, an early step in the repair process is assessed as the ability of a cellular extract to recognize and incise damaged DNA in substrate nucleoids from cells treated with a DNA-damaging compound. Our direct comparison of both assays in eight cell lines and human peripheral blood lymphocytes indicated no significant relationship between these DNA repair assays (R2 = 0.084, P = 0.52). The DNA incision activity of test cells measured with the in vitro repair assay correlated with the background level of DNA damage in the untreated test cells (R2 = 0.621, P = 0.012). When extracts were prepared from cells exposed to DNA-damaging agents (10 mM KBrO3 or 1 µM Ro 19-8022 plus light), the incision activity was significantly increased, which is in line with the notion that base excision repair is inducible. The data presented suggest that the two assays do not measure the same endpoint of DNA repair and should be considered as complementary.
Assuntos
Dano ao DNA , Reparo do DNA , Humanos , Ensaio Cometa , Linhagem Celular , DNARESUMO
In terrestrial plants, strigolactones act as multifunctional endo- and exo-signals. On microalgae, the strigolactones determine akin effects: induce symbiosis formation with fungi and bacteria and enhance photosynthesis efficiency and accumulation of biomass. This work aims to synthesize and identify strigolactone mimics that promote photosynthesis and biomass accumulation in microalgae with biotechnological potential. Novel strigolactone mimics easily accessible in significant amounts were prepared and fully characterized. The first two novel compounds contain 3,5-disubstituted aryloxy moieties connected to the bioactive furan-2-one ring. In the second group of compounds, a benzothiazole ring is connected directly through the cyclic nitrogen atom to the bioactive furan-2-one ring. The novel strigolactone mimics were tested on Chlorella sorokiniana NIVA-CHL 176. All tested strigolactones increased the accumulation of chlorophyll b in microalgae biomass. The SL-F3 mimic, 3-(4-methyl-5-oxo-2,5-dihydrofuran-2-yl)-3H-benzothiazol-2-one (7), proved the most efficient. This compound, applied at a concentration of 10-7 M, determined a significant biomass accumulation, higher by more than 15% compared to untreated control, and improved the quantum yield efficiency of photosystem II. SL-F2 mimic, 5-(3,5-dibromophenoxy)-3-methyl-5H-furan-2-one (4), applied at a concentration of 10-9 M, improved protein production and slightly stimulated biomass accumulation. Potential utilization of the new strigolactone mimics as microalgae biostimulants is discussed.
Assuntos
Chlorella , Microalgas , Chlorella/metabolismo , Biomassa , Fotossíntese , Microalgas/metabolismo , Furanos/farmacologia , Furanos/metabolismoRESUMO
Humic substances (HS) act as biostimulants for terrestrial photosynthetic organisms. Their effects on plants are related to specific HS features: pH and redox buffering activities, (pseudo)emulsifying and surfactant characteristics, capacity to bind metallic ions and to encapsulate labile hydrophobic molecules, ability to adsorb to the wall structures of cells. The specific properties of HS result from the complexity of their supramolecular structure. This structure is more dynamic in aqueous solutions/suspensions than in soil, which enhances the specific characteristics of HS. Therefore, HS effects on microalgae are more pronounced than on terrestrial plants. The reported HS effects on microalgae include increased ionic nutrient availability, improved protection against abiotic stress, including against various chemical pollutants and ionic species of potentially toxic elements, higher accumulation of value-added ingredients, and enhanced bio-flocculation. These HS effects are similar to those on terrestrial plants and could be considered microalgal biostimulant effects. Such biostimulant effects are underutilized in current microalgal biotechnology. This review presents knowledge related to interactions between microalgae and humic substances and analyzes the potential of HS to enhance the productivity and profitability of microalgal biotechnology.
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Poluentes Ambientais , Microalgas , Biotecnologia , Substâncias Húmicas/análise , Plantas , Solo/químicaRESUMO
Novel fluorescent strigolactone derivatives that contain the piperidine-substituted 1,8-naphthalimide ring system connected through an ether link to a bioactive 3-methyl-furan-2-one unit were synthesized and their spectroscopic properties investigated. The solvatochromic behavior of these piperidine-naphthalimides was monitored in solvents of different polarity using the electronic absorption and fluorescence spectra. These compounds exhibited a strong positive solvatochromism taking into account the change of solvent polarity, and the response mechanism was analyzed by fluorescence lifetime measurements. According to Catalan and [f(n), f(ε), ß, α] solvent scales, the dipolarity and polarizability are relevant to describe the solute-solvent interactions. The emission chemosensing activity was discussed in order to determine the water content in organic environments. The emission intensity of these compounds decreased rapidly in dioxane, increasing water level up to 10%. Measuring of quantum yield indicated that the highest values of quantum efficiency were obtained in nonpolar solvents, while in polar solvents these derivatives revealed the lowest quantum yield. The fluorescence decay can be described by a monoexponential model for low water levels, and for higher water contents a biexponential model was valid.
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Naftalimidas , Água , Fluorescência , Naftalimidas/química , Piperidinas , Solventes/química , Espectrometria de Fluorescência , Água/químicaRESUMO
Research background: Various protocols for enzymatic hydrolysis of fish by-products are increasingly tested to ensure value-added products with functional and biological properties important for food, cosmetic and medical applications. In addition, they attempt to minimize waste from industrial processing and environmental requirements. This study aims to establish an efficient protocol based on two-step enzymatic hydrolysis of freshwater fish skin and to evaluate the effect of resulting bioactive peptides on free radical scavenging, redox balance and regulation of fibroblast proliferation and migration. Experimental approach: Pepsin-soluble collagen extracted from silver carp (Hypophthalmichthys molitrix) skin was hydrolyzed by proteinase K at specific sites under controlled conditions. The molecular mass of ultrafiltration permeate was determined by gradient electrophoresis and gel filtration chromatography. The biological activity of intermediate and small size bioactive peptides was evaluated in experimental models in vitro mimicking oxidative stress and skin wound conditions. Results and conclusions: Extracted fish collagen was hydrolysed using proteinase K, the most efficient enzyme for the cleavage of the primary structure of the molecule, as previously found in silico. Established optimal conditions increased the enzyme specificity and the process yield. Bioactive peptides exerted significantly higher scavenging activity on free stable radicals and hydroxyl radicals often found in vivo, compared to fish collagen. They stimulated fibroblast metabolism in a dose-dependent manner and up-regulated cell migration in a scratch wound model. Pretreatment of fibroblasts with induced oxidative stress using optimal concentrations of fish peptides prevented the increase of reactive oxygen species production. In conclusion, bioactive peptides from carp skin demonstrated valuable properties of maintaining redox balance and skin wound healing process improvement, which indicated further potential applications in the development of pharmaceutical and nutraceutical formulations. Novelty and scientific contribution: In this study the enzymatic hydrolysis was applied to isolated protein, in contrast to previous studies using waste tissue with variable composition. Recovered bioactive peptides acted not only as antioxidant agents, but also as regulators of oxidative stress and wound healing processes in skin cell models. Their nutritional and cosmetic application is recommended in novel formulations fighting skin ageing phenomena.
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In the present study, we evaluated for the first time the photoprotective effect of fish bone bioactive peptides (FBBP) preparation isolated from silver carp (Hypophthalmichthys molitrix) discarded tissue using in vitro experimental models of skin cells exposed to ultraviolet B (UVB) irradiation and stressing agents. FBBP preparation was obtained by papain treatment of minced bones and centrifugal ultrafiltration, and the molecular weight (MW) distribution was characterized by size exclusion and reversed-phase high performance liquid chromatography (RP-HPLC). In vitro assessment of the effect of FBBP pretreatment in UVB-irradiated L929 fibroblasts and HaCaT keratinocytes revealed their cytoprotective activity. Their capacity to efficiently reduce reactive oxygen species (ROS) production and lipid peroxidation varied in a dose-dependent manner, and it was greater in fibroblasts. A decrease of proinflammatory cytokines secretion, in particular of tumor necrosis factor alpha (TNF-α), was found after FBBP pretreatment of THP-1-derived inflamed macrophages. Melanin production and tyrosinase activity investigated in UVB-irradiated Mel-Juso cells were lowered in direct relation to FBBP concentrations. FBBP fractions with high radical scavenging activity were separated by ion exchange chromatography, and two collagenic sequences were identified. All these results offer new scientific data on aquaculture fish bone-derived peptides confirming their ability to control the antioxidant, anti-inflammatory and pigmentation processes developed during UV irradiation of skin cells and recommend their use as valuable natural ingredients of photoprotective cosmeceutical products.
Assuntos
Osso e Ossos/efeitos dos fármacos , Inflamação/patologia , Peptídeos/farmacologia , Pigmentação , Pele/efeitos da radiação , Raios Ultravioleta , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Citoproteção/efeitos dos fármacos , Citoproteção/efeitos da radiação , Peixes , Células HaCaT/efeitos dos fármacos , Células HaCaT/efeitos da radiação , Humanos , Mediadores da Inflamação/metabolismo , Espaço Intracelular/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Malondialdeído/metabolismo , Melaninas/biossíntese , Camundongos , Peso Molecular , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Peptídeos/isolamento & purificação , Pigmentação/efeitos dos fármacos , Pigmentação/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria Ultravioleta , Células THP-1RESUMO
Rapeseed meal (RSM), a by-product of oilseed extraction connected to the agri-food and biofuel sectors, is currently used as animal feed and for other low-value purposes. With a biorefinery approach, RSM could be valorized as a source of bio-based molecules for high-value applications. This study provides a chemical characterization of RSM in the perspective of its valorization. A qualitative study of main functional groups by fourier transform infrared (FTIR) spectroscopy was integrated with a chemical characterization of macronutrients, minerals by inductively coupled plasma optical emission spectrometry (ICP-OES), phenolic acids and lipid components by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), HPLC-diode-array detector (HPLC-DAD) and gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID). The study, conducted on different lots of RSM collected over a one-year period from an oil pressing factory serving a biofuel biorefinery, highlighted a constant quality over time of RSM, characterized by high protein (31-34%), fiber (33-40%) and mineral (5.5-6.8%) contents. Polyphenol extracts showed a significant antioxidant activity and a prevalence of sinapic acid, accounting for more than 85% of total phenolic acids (395-437 mg kg-1 RSM). Results highlight the potentialities of RSM for further valorization strategies that may lead to the creation of new cross-sector interconnections and bio-based value chains with improvement of the economics and sustainability of the bioeconomy sectors involved.
Assuntos
Brassica napus/química , Resíduos Industriais/análise , Gerenciamento de Resíduos/métodos , Ração Animal/análise , Antioxidantes/química , Biocombustíveis/análise , Brassica napus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos Industriais/economia , Minerais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas em Tandem/métodos , Resíduos/análiseRESUMO
Two chitosan extracts were prepared by chemical and enzymatic treatment of Ganoderma lucidum mushroom, as an alternative source to crustacean shells. The molecular weight of the enzymatic extract was lower than that of the chemical one and of shrimp chitosan, as determined by viscosity measurements. Characteristic signals were identified in the 1 H-NMR spectra and high deacetylation degree indicated good physico-chemical properties for both mushroom chitosan extracts. The scavenging capacity of mushroom chitosan extracts was moderate against the synthetic radicals of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), but higher values were observed for the enzymatic extract, compared to the chemical extract and shrimp chitosan. In vitro cytotoxicity was evaluated in L929 mouse fibroblast cell lines and the results of MTT assay showed good cytocompatibility in the tested range of concentrations. The growth of Gram-positive bacteria was inhibited more than Gram-negative bacteria in the presence of mushroom chitosan extracts, in particular by the chemical one, indicating their efficiency as antimicrobial agents. All these results strengthen the evidence of mushroom polysaccharide preparations availability for biomedical applications.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Quitosana/farmacologia , Reishi/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Quitosana/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Picratos/antagonistas & inibidores , Relação Estrutura-Atividade , Ácidos Sulfônicos/antagonistas & inibidoresRESUMO
Cystoseira barbata is an edible brown seaweed, traditionally used in the Black Sea area as functional food. Both alginate and brown seaweed biomass are well known for their potential use as adsorbents for heavy metals. Alginate was extracted from C. barbata recovered from the Romanian coast on the Black Sea with a yield of 19 ± 1.5% (w/w). The structural data for the polysaccharide was obtained by HPSEC-MALS, 1H-NMR. The M/G ratio was determined to be 0.64 with a molecular weight of 126.6 kDa with an intrinsic viscosity of 406.2 mL/g. Alginate beads were used and their adsorption capacity with respect to Pb2+ and Cu2+ ions was determined. The adsorption kinetics of C. barbata dry biomass was evaluated and it was shown to have an adsorption capacity of 279.2 ± 7.5 mg/g with respect to Pb2+, and 69.3 ± 2 with respect to Cu2+. Alginate in the form of beads adsorbs a maximum of 454 ± 4.7 mg/g of Pb2+ ions and 107.3 ± 1.7 mg/g of Cu2+ ions.
Assuntos
Alginatos/química , Alga Marinha/química , Adsorção , Biomassa , Mar Negro , Metais Pesados/química , Peso Molecular , Polissacarídeos/química , Romênia , ViscosidadeRESUMO
Aflatoxins, which are mainly produced by Aspergillus flavus and parasiticus growing on plants and products stored under inappropriate conditions, represent the most studied group of mycotoxins. Contamination of human and animal milk with aflatoxin M1, the hydroxylated metabolite of aflatoxin B1, is an important health risk factor due to its carcinogenicity and mutagenicity. Due to the low concentration of this aflatoxin in milk and milk products, the analytical methods used for its quantification have to be highly sensitive, specific and simple. This paper presents an overview of the analytical methods, especially of the electrochemical immunosensors and aptasensors, used for determination of aflatoxin M1.
Assuntos
Laticínios , Leite , Aflatoxinas , Animais , Técnicas Eletroquímicas , Contaminação de Alimentos , HumanosRESUMO
The importance of strigolactones in plant biology prompted us to synthesize simplified strigolactone mimics effective as exogenous signals for rhizosphere organisms. New strigolactone mimics easily derived from simple and available starting materials in significant amounts were prepared and fully characterized. These compounds contain an aromatic or heterocyclic ring, usually present in various bioactive molecules, connected by an ether link to a furan-2-one moiety. The new synthesized strigolactone mimics were confirmed to be active on plant pathogenic fungi and parasitic weed seeds.
Assuntos
Ascomicetos/efeitos dos fármacos , Materiais Biomiméticos/síntese química , Lactonas/química , Plantas Daninhas/efeitos dos fármacos , Pirimidinas/síntese química , Rizosfera , Ascomicetos/crescimento & desenvolvimento , Materiais Biomiméticos/farmacologia , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Lactonas/isolamento & purificação , Lactonas/farmacologia , Orobanchaceae/efeitos dos fármacos , Orobanchaceae/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Daninhas/crescimento & desenvolvimento , Pirimidinas/farmacologia , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimentoRESUMO
Several 3,5-disubstituted isoxazoles were obtained in good yields by regiospecific 1,3-dipolar cycloaddition reactions between aromatic nitrile oxides, generated in situ from the corresponding hydroxyimidoyl chlorides, with non-symmetrical activated alkynes in the presence of catalytic amounts of copper(I) iodide. Effects of 3,5-disubstituted isoxazoles on nitric oxide and reactive oxygen species generation in Arabidopsis tissues was studied using specific diaminofluoresceine dyes as fluorescence indicators.
RESUMO
For the first time the electropolymerization of 2,6-dihydroxynaphthalene (2,6-DHN) on a screen printed carbon electrode (SPCE) was investigated and evaluated for peroxynitrite (PON) detection. Cyclic voltammetry was used to electrodeposit the poly(2,6-DHN) on the carbon electrode surface. The surface morphology and structure of poly(2,6-DHN) film were investigated by SEM and FTIR analysis, and the electrochemical features by cyclic voltammetry. The poly(2,6-DHN)/SPCE sensor showed excellent electrocatalytic activity for PON oxidation in alkaline solutions at very low potentials (0-100 mV vs. Ag/AgCl pseudoreference). An amperometric FIA (flow injection analysis) system based on the developed sensor was optimized for PON measurements and a linear concentration range from 2 to 300 µM PON, with a LOD of 0.2 µM, was achieved. The optimized sensor inserted in the FIA system exhibited good sensitivity (4.12 nA·µM-1), selectivity, stability and intra-/inter-electrode reproducibility for PON determination.
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The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA) and its alkaline salt (OLANa). Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA), with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na⺠= 2:1, the molar ratio (OLA/OLANa = 1:1) required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES) was added in a sodium silicate sol-gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC) (TG-DSC) analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids' final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules.
Assuntos
Materiais Biocompatíveis/síntese química , Preparações de Ação Retardada/síntese química , Ácido Oleico/química , Silicatos/química , Dióxido de Silício/química , Álcalis/química , Cátions Monovalentes , Interações Hidrofóbicas e Hidrofílicas , Transição de Fase , Silanos/química , Sódio/química , TermodinâmicaRESUMO
Seed coating ensures the targeted delivery of various compounds from the early stages of development to increase crop quality and yield. Silicon and alginate are known to have plant biostimulant effects. Rice husk (RH) is a significant source of biosilica. In this study, we coated mung bean seeds with an alginate-glycerol-sorbitol (AGS) film with embedded biogenic nanosilica (SiNPs) from RH, with significant plant biostimulant activity. After dilute acid hydrolysis of ground RH in a temperature-controlled hermetic reactor, the resulting RH substrate was neutralized and calcined at 650°C. The structural and compositional characteristics of the native RH, the intermediate substrate, and SiNPs, as well as the release of soluble Si from SiNPs, were investigated. The film for seed coating was optimized using a mixture design with three factors. The physiological properties were assessed in the absence and the presence of 50 mM salt added from the beginning. The main parameters investigated were the growth, development, metabolic activity, reactive oxygen species (ROS) metabolism, and the Si content of seedlings. The results evidenced a homogeneous AGS film formation embedding 50-nm amorphous SiNPs having Si-O-Si and Si-OH bonds, 0.347 cm3/g CPV (cumulative pore volume), and 240 m2/g SSA (specific surface area). The coating film has remarkable properties of enhancing the metabolic, proton pump activities and ROS scavenging of mung seedlings under salt stress. The study shows that the RH biogenic SiNPs can be efficiently applied, together with the optimized, beneficial alginate-based film, as plant biostimulants that alleviate saline stress from the first stages of plant development.
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Selenium nanoparticles (SeNPs) have specific properties that result from their biosynthesis particularities. Chitosan can prevent pathogenic biofilm development. A wide palette of bacterial nanocellulose (BNC) biological and physical-chemical properties are known. The aim of this study was to develop a hydrogel formulation (SeBNCSFa) based on ferulic acid-grafted chitosan and bacterial nanocellulose (BNC) enriched with SeNPs from Kombucha fermentation (SeNPsK), which could be used as an adjuvant for oral implant integration and other applications. The grafted chitosan and SeBNCSFa were characterized by biochemical and physical-chemical methods. The cell viability and proliferation of HGF-1 gingival fibroblasts were investigated, as well as their in vitro antioxidant activity. The inflammatory response was determined by enzyme-linked immunosorbent assay (ELISA) of the proinflammatory mediators (IL-6, TNF-α, and IL-1ß) in cell culture medium. Likewise, the amount of nitric oxide released was measured by the Griess reaction. The antimicrobial activity was also investigated. The grafting degree with ferulic acid was approximately 1.780 ± 0.07% of the total chitosan monomeric units, assuming single-site grafting per monomer. Fourier-transform infrared spectroscopy evidenced a convolution of BNC and grafted chitosan spectra, and X-ray diffraction analysis highlighted an amorphous rearrangement of the diffraction patterns, suggesting multiple interactions. The hydrogel showed a high degree of cytocompatibility, and enhanced antioxidant, anti-inflammatory, and antimicrobial potentials.
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The recovery of plant mineral nutrients from the bio-based value chains is essential for a sustainable, circular bioeconomy, wherein resources are (re)used sustainably. The widest used approach is to recover plant nutrients on the last stage of biomass utilization processes-e.g., from ash, wastewater, or anaerobic digestate. The best approach is to recover mineral nutrients from the initial stages of biomass biorefinery, especially during biomass pre-treatments. Our paper aims to evaluate the nutrient recovery solutions from a trans-sectorial perspective, including biomass processing and the agricultural use of recovered nutrients. Several solutions integrated with the biomass pre-treatment stage, such as leaching/bioleaching, recovery from pre-treatment neoteric solvents, ionic liquids (ILs), and deep eutectic solvents (DESs) or integrated with hydrothermal treatments are discussed. Reducing mineral contents on silicon, phosphorus, and nitrogen biomass before the core biorefinery processes improves processability and yield and reduces corrosion and fouling effects. The recovered minerals are used as bio-based fertilizers or as silica-based plant biostimulants, with economic and environmental benefits.
Assuntos
Minerais , Águas Residuárias , Biomassa , Fósforo , Plantas , NutrientesRESUMO
In our previous research, we demonstrated that honey and its biomimetic natural deep eutectic solvent (NaDES) modulate the antioxidant activity (AOA) of the raspberry extract (RE). In this study, we evaluated the AOA behaviour of the mixture honey/NaDES-honeysuckle (Lonicera caprifolium, LFL) extract and compared it with the mixture honey/NaDES-RE. These two extracts have similar major flavonoids and hydroxycinnamic acid compounds but differ in their total content and the presence of anthocyanins in RE. Therefore, it was of interest to see if the modulation of the LFL polyphenols by honey/NaDES was similar to that of RE. We also evaluated the prebiotic activity of these mixtures and individual components on Limosilactobacillus reuteri DSM 20016. Although honey/NaDES modulated the AOA of both extracts, from synergism to antagonism, the modulation was different between the two extracts for some AOA activities. Honey/NaDES mixtures enriched with LFL and RE did not show significant differences in bacterial growth stimulation. However, at a concentration of 45 mg/mL, the honey -LFL mixture exhibited a higher effect compared to the honey-RE mixture. The antioxidant and prebiotic properties of mixtures between honey and polyphenol-rich extracts are determined by multiple interactions in complex chemical systems.