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The VEMoS-AXL system is a new optical biometer based on spectral domain optical coherence tomography (SD-OCT) that has been tested in terms of intrasession repeatability and compared with a swept-source optical coherence tomography biometer (SS-OCT), which is recognized as the gold standard for the performance of an agreement analysis. A biometric analysis was performed three consecutive times in 120 healthy eyes of 120 patients aged between 18 and 40 years with the SD-OCT system, and afterwards, a single measurement was obtained with the SS-OCT system. Within-subject standard deviations were 0.004 mm, 4.394 µm, and 0.017 mm for axial length (AL), central corneal thickness (CCT), and anterior chamber depth (ACD) measures obtained with the SD-OCT biometer, respectively. The agreement between devices was good for AL (limits of agreement, LoA: -0.04 to 0.03 mm) and CCT (LoA: -4.36 to 14.38 µm), whereas differences between devices were clinically relevant for ACD (LoA: 0.03 to 0.21 mm). In conclusion, the VEMoS-AXL system provides consistent measures of anatomical parameters, being most of them interchangeable with those provided by the SS-OCT-based gold standard.
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This study aimed to assess the nutritional quality and digestibility of proteins in two red seaweed species, Gelidium corneum and Gracilaropsis longissima, through the application of in vitro gastrointestinal digestions, and evaluate the impact of two consecutive processing steps, extrusion and compression moulding, to produce food snacks. The protein content in both seaweeds was approximately 16 %, being primarily located within the cell walls. Both species exhibited similar amino acid profiles, with aspartic and glutamic acid being most abundant. However, processing impacted their amino acid profiles, leading to a significant decrease in labile amino acids like lysine. Nevertheless, essential amino acids constituted 35-36 % of the total in the native seaweeds and their processed products. Although the protein digestibility in both seaweed species was relatively low (<60 %), processing, particularly extrusion, enhanced it by approximately 10 %. Interestingly, the effect of the different processing steps on the digestibility varied between the two species. This difference was mainly attributed to compositional and structural differences. G. corneum exhibited increased digestibility with each processing step, while G. longissima reached maximum digestibility after extrusion. Notably, changes in the amino acid profiles of the processed products affected adversely the protein nutritional quality, with lysine becoming the limiting amino acid. These findings provide the basis for developing strategies to enhance protein quality in these seaweed species, thereby facilitating high-quality food production with potential applications in the food industry.
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Algas Comestíveis , Lisina , Rodófitas , Alga Marinha , Digestão , Proteínas , Aminoácidos/química , Parede Celular/metabolismo , Alga Marinha/químicaRESUMO
Rice straw is a widely produced residue that can be converted into value-added products. This work aimed at using greener processes combining mild alkali (A), ozone (O) and enzymatic (engineered xylanase) (E) treatments to extract cellulose and other value-added compounds from rice straw and to evaluate the effects of the order of the treatments. Solid (S) and liquid (L) fractions from the process were collected for physicochemical characterization. AOE treatment showed the best capacity to extract high purity cellulose and other valuable compounds. The lignin content was significantly decreased independently of the order of the treatments and, its content in the extract obtained after the AOE process was lower than the one obtained after the OAE process. Moreover, thermal stability of the samples increased after the enzymatic process, being higher in SAOE. The alkaline treatment increased the hemicellulose and polyphenol content (antioxidant activity) in the liquid fractions (LA and LOA). In contrast, the ozonized liquid fractions had lower polyphenol content. Therefore, alkali was fundamental in the process. In conclusion, the AOE strategy could be a more environmentally friendly method for extracting cellulose and other valuable compounds, which could be used to develop active materials in the future.
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Celulose , Oryza , Celulose/química , Oryza/química , Hidrólise , Lignina/química , Álcalis , PolifenóisRESUMO
This study aimed to examine the composition and properties of the invasive macroalgae R. okamurae and explore potential applications. The results showed that the seaweed biomass is mainly composed of structural carbohydrates, with alginate being the main constituent, accounting for 32 % of its total composition and with a mannuronic and guluronic acid ratio (M/G) ratio of 0.93. It also has a relatively high concentration of fucose, related to the presence of fucoidans that have important biological functions. Among the mineral contents, a high magnesium and calcium (7107 and 5504 mg/kg) concentration, and the presence of heavy metals above legislated thresholds, were notable. R. okamurae also contained a high lipid content of 17 %, mainly composed of saturated fatty acids, but with a significant fraction of n3 polyunsaturated fatty acids (18 %) resulting in a low n6/n3 ratio (0.31), that has health benefits. The protein content of R. okamurae was 12 %, with high-quality proteins, as essential amino acids (mainly leucine, phenylalanine and valine) constitute 32 % of the total amino acids. It also showed a high polyphenol content and outstanding antioxidant properties (106.88 mg TE/g). Based on these findings, R. okamurae has significant potential as a sustainable source of bioactive compounds that can add value to different sectors, including food, feed, pharmaceuticals and cosmetics.
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Phaeophyceae , Alga Marinha , Alga Marinha/química , Biomassa , Ácidos Graxos/metabolismo , Proteínas/metabolismoRESUMO
PURPOSE: The aim of the study was to compare distance vision measurements obtained with video oculography (VOG) and an alternate prism cover test (APCT). DESIGN: Single-center, retrospective, and cross-sectional. METHODS: Eighty-seven subjects with strabismus were included. All patients underwent an optometric examination. The measurement of strabismus in distance vision was performed with the best optical correction using the APCT and the VOG GazeLab. Subjects were divided according to the type of strabismus; 41 were esotropic and 46 were exotropic. RESULTS: The general comparison of APCT and VOG showed a mean difference of 0.60±2.74 prism diopters (Δ), not observing statistical differences between both methods ( P =0.059) and presenting a correlation of 0.976 ( P <0.001). Using APCT, the mean amount of esotropia for the group was 18.31±11.64 Δ and that of exotropia was 19.62±8.80 Δ. Compared with the VOG, the mean value of esotropia for the group was 18.65±11.65 Δ and that of exotropia was 19.48±8.62 Δ. The means are statistically different for the esotropia group ( P =0.005) but not for the exotropia group ( P =0.318). There was a high direct correlation between the methods of measurement for both the esotropic ( R =0.980; P <0.001) and exotropic patients ( R =0.975; P <0.001). Bland-Altman analysis shows a mean difference of 1.37±2.76 Δ for the esotropia patients and 0.31±2.66 Δ for the exotropic patients, respectively. CONCLUSIONS: This study demonstrated comparable results in measuring strabismus between VOG and APTC for esotropia and exotropia, with an excellent correlation between both methods and good agreement, especially in subjects with exotropia.
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Esotropia , Exotropia , Estrabismo , Humanos , Esotropia/diagnóstico , Exotropia/diagnóstico , Estudos Retrospectivos , Estudos Transversais , Estrabismo/diagnóstico , Músculos OculomotoresRESUMO
In this work, aqueous extracts from six different Pleurotus species were obtained and their yield, gross composition, ß-glucan content, monosaccharide profile, thermal stability, molecular weight distribution, and FT-IR were analyzed before and after purification through ethanol precipitation of the carbohydrate-rich fractions. The bioactivity (anti-inflammatory and immunomodulatory activity) of the various fractions obtained was also analyzed in three different cell cultures and compared with a lentinan control. The trend observed after purification of the aqueous fractions was an increase in the concentration of polysaccharides (especially ß-glucans), a decrease in ash, glucosamine and protein content and the elimination of low molecular weight (Mw) compounds, thus leaving in the purified samples high Mw populations with increased thermal stability. Interestingly, all these purified fractions displayed immunomodulatory capacity when tested in THP-1 macrophages and most of them also showed significant activity in HEK-hTLR4 cells, highlighting the bioactivity observed for Pleurotus ostreatus (both the extracts obtained from the whole mushroom and from the stipes). This specific species was richer in heteropolysaccharides, having moderate ß-glucan content and being enriched upon purification in a high Mw fraction with good thermal stability.
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Agaricales , Pleurotus , beta-Glucanas , beta-Glucanas/farmacologia , Pleurotus/química , Espectroscopia de Infravermelho com Transformada de Fourier , Polissacarídeos/químicaRESUMO
Alginates are industrially relevant polysaccharides widely used in the food and biomedical industries for their excellent gelling properties. The growing emphasis on the valorization of marine resources has evidenced the need for alternative methods for the determination of both alginate content and the M/G ratio. This study describes the application of acid methanolysis and separation by anion exchange chromatography. Five samples, including alginates extracted from Saccharina latissima, Ascophyllum nodosum, a certified standard, and two poly-uronates (Poly-M and Poly-G), were analysed for their M/G ratio and alginate content at different treatment conditions, and compared with other conventionally used or reference methods (NMR, FTIR, and colorimetric methods). Quantitative estimation of alginate was relatively accurate at optimum conditions (4 h at 100 °C), as compared with the certified standard or with other colorimetric methods. M/G ratios were not significantly different from those determined after the reference method (1H NMR) or compared to FTIR protocols. The results evidence that methanolysis may be applied to simultaneously estimate the purity and M/G ratio of alginate-rich samples in a single analysis.
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Alginatos , Cromatografia , Ânions , Colorimetria , Alimentos , Poli ARESUMO
Bovine mastitis is a costly disease in the dairy sector worldwide. Here the objective was to identify and characterize anti-biofilm compounds produced by Bacillus spp. against S. aureus associated with bovine mastitis. Results showed that cell-free supernatants of three Bacillus strains (out of 33 analysed) reduced S. aureus biofilm formation by approximately 40 % without affecting bacterial growth. The anti-biofilm activity was associated with exopolysaccharides (EPS) secreted by Bacillus spp. The EPS decreased S. aureus biofilm formation in a dose-dependent manner, inhibiting biofilm formation by 83 % at 1 mg/mL. The EPS also showed some biofilm disruption activity (up to 36.4 %), which may be partially mediated by increased expression of the aur gene. The characterization of EPS produced by Bacillus velezensis 87 and B. velezensis TR47II revealed macromolecules with molecular weights of 31.2 and 33.7 kDa, respectively. These macromolecules were composed mainly of glucose (mean = 218.5 µg/mg) and mannose (mean = 241.5 µg/mg) and had similar functional groups (pyranose ring, beta-type glycosidic linkage, and alkynes) as revealed by FT-IR. In conclusion, this study shows the potential applications of EPS produced by B. velezensis as an anti-biofilm compound that could contribute to the treatment of bovine mastitis caused by S. aureus.
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Bacillus , Mastite Bovina , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Staphylococcus aureus/genética , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Espectroscopia de Infravermelho com Transformada de Fourier , Infecções Estafilocócicas/microbiologia , BiofilmesRESUMO
The effects of the high hydrostatic pressure (HPP) pre-treatment on the alginate extraction were seen to greatly depend on the recalcitrant nature of two algae species. Alginates were deeply characterized in terms of composition, structure (HPAEC-PAD, FTIR, NMR, SEC-MALS), functional and technological properties. The pre-treatment significantly increased the alginate yield in the less recalcitrant A. nodosum (AHP) also favoring the extraction of sulphated fucoidan/fucan structures and polyphenols. Although the molecular weight was significantly lower in AHP samples, neither the M/G ratio nor the M and G sequences were modified. In contrast, a lower increase in alginate extraction yield was observed for the more recalcitrant S. latissima after the HPP pre-treatment (SHP), but it significantly affected the M/G values of the resulting extract. The gelling properties of the alginate extracts were also explored by external gelation in CaCl2 solutions. The mechanical strength and nanostructure of the hydrogel beads prepared were determined using compression tests, synchrotron small angle X-ray scattering (SAXS), and cryo-scanning electron microscopy (Cryo-SEM). Interestingly, the application of HPP significantly improved the gel strength of SHP, in agreement with the lower M/G values and the stiffer rod-like conformation obtained for these samples.
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Alginatos , Pressão Hidrostática , Espalhamento a Baixo Ângulo , Difração de Raios X , Microscopia CrioeletrônicaRESUMO
PURPOSE: To evaluate clinical retinal optical image quality following implantation of an extended depth of focus intraocular lens (EDOF IOL) (Vivity; Alcon Laboratories, Inc), and to compare it with a monofocal and a trifocal IOL. METHODS: This prospective, comparative, case-control study included 88 eyes implanted with: (1) 19 monofocal IOLs (AcrySof SA60AT; Alcon Laboratories, Inc); (2) 38 EDOF IOLs (AcrySof IQ Vivity); and (3) 31 trifocal IOLs (AT LISA tri 839MP; Carl Zeiss Meditec AG). Total root mean square, ocular lower (LOA) and higher (HOA) order aberrations, point spread function (PSF) Strehl ratio (PSF with LOA), and PSF Strehl ratio excluding LOA (PSF without LOA) were analyzed using a Pyramidal WaveFront-based sensor aberrometer Osiris (Costruzione Strumenti Oftalmici) at two different pupil sizes (3 and 4 mm). RESULTS: The trifocal IOL showed the highest PSF without LOA at both pupil sizes (0.52 ± 0.12 and 0.31 ± 0.07, respectively), followed by the AcrySof SA60AT (0.39 ± 0.10 and 0.27 ± 0.07) and AcrySof IQ Vivity (0.34 ± 0.11 and 0.24 ± 0.09) (P < .001). The AcrySof IQ Vivity and monofocal IOLs were comparable (P > .05). Despite the comparable postoperative low spherical equivalent among the IOL groups, the AT LISA tri 839MP retinal image quality (PSF with LOA) was the most severely affected by such residual refractive errors (dropped to 0.26 ± 0.06 at 3 mm; P < .001) compared to the monofocal AcrySof SA60AT (0.24 ± 0.07 at 3 mm) and EDOF Acrysof IQ Vivity (0.23 ± 0.06 at 3 mm) groups. The PSF with LOA was comparable (P > .05) among the three groups at both the 3-and 4-mm pupil size. CONCLUSIONS: Although trifocal IOLs provided significantly better retinal image quality if influence of LOA is excluded, they also demonstrated to be the most sensitive to residual refractive errors. Both the EDOF Acrysof IQ Vivity and mono-focal AcrySof SA60AT IOLs showed a comparable retinal image quality, and they are also comparable with trifocal IOLs when considering the clinically real PSF (PSF with LOA). [J Refract Surg. 2023;39(2):103-110.].
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Lentes Intraoculares , Facoemulsificação , Erros de Refração , Humanos , Estudos Prospectivos , Estudos de Casos e Controles , Refração Ocular , Desenho de PróteseRESUMO
In this work, a sequential fractionation protocol (cold and hot aqueous and alkaline extractions) and detailed compositional analysis (gross composition, monosaccharide analysis, FTIR, TGA) was applied to three relevant mushrooms in terms of global production (Grifola frondosa, Lentinula edodes and Pleurotus ostreatus) aiming to understand what is preferentially extracted during fractionation and how ß-glucan extraction is affected by mushroom source. Room temperature aqueous extracts showed highest overall yields (56.3-82%) consisting of proteins, sugars and polyphenols. ß-glucan content was highest in P. ostreatus and was concentrated in the more soluble fractions. On the contrary, a recalcitrant ß-glucan in G. frondosa was mainly present in the residue (7.38%). L. edodes showed ß-glucan populations distributed along aqueous and alkaline extracts, higher abundance of non-glucan polysaccharides and higher chitin purity (47.78%) in the residue. This work sets the basis for the rational design of extraction processes aiming to valorise mushroom biomass.
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Agaricales , Cogumelos Shiitake , beta-Glucanas , Agaricales/metabolismo , beta-Glucanas/química , Cogumelos Shiitake/química , Polissacarídeos/química , Monossacarídeos , Água , QuitinaRESUMO
BACKGROUND: The physicochemical and functional properties of pectin (JFP) extracted from edible portions (including pericarp and seed) of raw jackfruit (an underutilized tropical fruit) at four different maturity stages (referred to as stages I, II, III, and IV) were characterized in terms of extraction yields, chemical composition, molecular weight, and antioxidant properties to evaluate its potential use in foods. RESULT: The JFP yield increased from 9.7% to 21.5% with fruit maturity, accompanied by an increase in the galacturonic acid content (50.1%, 57.1%, 63.6%, and 65.2%) for stages I-IV respectively. The molecular weight increased from 147 kDa in stage I to 169 kDa in stage III, but decreased to 114 kDa in stage IV, probably due to cell-wall degradation during maturation. The JFP was of the high methoxyl type and the degree of esterification increased from 65% to 87% with fruit maturity. The functional properties of JFP were similar to or better than those reported for commercial apple pectin, thus highlighting its potential as a food additive. Although the phenolics and flavonoids content of JFP decreased with fruit maturity, their antioxidant capacity increased, which may be correlated with the increased content of galacturonic acid upon fruit development. Gels prepared from JFP showed viscoelastic behavior. Depending on the maturity stage in which they were obtained, different gelation behavior was seen. CONCLUSION: The study confirmed the potential of pectin extracted from edible parts of jackfruit as a promising source of high-quality gelling pectin with antioxidant properties, for food applications. © 2022 Society of Chemical Industry.
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Artocarpus , Pectinas , Pectinas/química , Artocarpus/química , Antioxidantes/análise , Frutas/químicaRESUMO
Electrosprayed agar nanocapsules were developed using an acetic acid solution as solvent. The role of solution properties (viscosity, surface tension, and conductivity) in the formation of agar particles was assessed, together with the effect of both agar and acetic acid concentrations on the size and morphology of the resulting particles. Agar solutions with a concentration below 10% w/v were not suitable for electrospraying. Furthermore, the agar-acetic acid ratio was also critical for the formation of agar nanostructures (with an optimum ratio of 1:2). A decrease in particle size was also observed when decreasing agar concentration, with particle diameter values ranging between 50 and 400 nm. Moreover, the suitability of the electrosprayed agar nanocapsules as carriers for a model bioactive compound, chlorophyllin sodium copper salt (CHL), was also evaluated. The release profile of encapsulated CHL, with an estimated encapsulation efficiency of around 40%, was carried out in food simulants with different hydrophilicity (10% v/v and 50% v/v ethanol). While the release of the bioactive was negligible in the hydrophilic food simulant, an initial burst release followed by a slower sustained release was observed when the capsules were immersed in 50% ethanol solution. The results open up a broad range of possibilities that deserve further exploration related to the use of these edible polysaccharide-based nanocapsules.
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The alginate industry processes more than hundred thousand tons per year of algae in Europe, discarding around 80% of the algae biomass as different solid/liquid residual streams. In this work, Saccharina latissima and Ascophyllum nodosum, their generated alginates and all residual fractions generated in the process were characterized in terms of lipid, ash, protein content, and the carbohydrate composition and antioxidant capacities analyzed. The first fraction after acid treatment (ca. 50% of the initial dry biomass) was rich in phlorotannins (15 mg GAE/g) and bioactive fucoidans (15-70%), with a high sulfation degree in A. nodosum. Two fractions generated from the solid residue, one soluble and another insoluble (Ra and Rb, respectively), constituted 9% and 5-8% of the initial biomass and showed great potential as a source of soluble protein (30% for S. latissima), and cellulose (70%) or fucoidan, respectively. Valorization strategies are suggested for these waste streams, evidencing their high potential as bioactive, texturizing or nutritional added-value ingredients for cosmetic, food, feed or pharmaceutical applications.
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Ascophyllum , Phaeophyceae , Alginatos , Antioxidantes , Ascophyllum/química , Resíduos Industriais , Phaeophyceae/químicaRESUMO
PURPOSE: To evaluate changes in keratoconic corneas implanted with intrastromal corneal ring segments (ICRSs) that have been explanted because of late extrusion of the segment after >2 years. SETTING: Vissum Miranza, Alicante, Spain; OftalmoSalud, Lima, Peru; Minya University Hospital, Egypt. DESIGN: Retrospective multicenter case series. METHODS: 23 keratoconic corneas that were implanted for ≥2 years and explanted because of natural extrusion of the segment. Clinical measures of visual, refractive, topographic, pachymetric, and aberrometric data were analyzed. To perform exploratory factor analysis, the Kaiser-Meyer-Olkin (KMO) test was used to evaluate sampling adequacy. Factor analysis with VARIMAX rotation was used to determine the main factors of the inventory. RESULTS: The mean time interval was 5 years. Topographic findings were reversed nearly to the baseline level after segment explantation (Km: 48.97 ± 3.47 D pre implantation and 47.60 ± 3.67 D after explantation, P =.374). Significant worsened in refractive cylinder was found pre-ICRS extrusion (â2.54 ± 3.40 D after implantation and â3.96 ± 1.72 before extrusion, P < .05). The main factor obtained in the preimplantation moment included keratoconus grade, keratometric readings, and visual acuities. After ICRS implantation, the most strength components were the refractive cylinder, corrected distance visual acuity, and uncorrected distance visual acuity. Corneal aberrations were the main factors in the pre-explantation analysis. CONCLUSIONS: ICRSs were safely extracted, with a reversal of the corneal topographic data to the preoperative level. A significant astigmatic change was shown in patients implanted with ICRSs before late extrusion of the segment, suggesting the role of this parameter as a prognostic factor of extrusion.
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Substância Própria , Ceratocone , Substância Própria/cirurgia , Topografia da Córnea , Humanos , Ceratocone/diagnóstico , Ceratocone/cirurgia , Próteses e Implantes , Implantação de Prótese , Refração Ocular , Estudos RetrospectivosRESUMO
In recent years, food ingredients rich in bioactive compounds have emerged as candidates to prevent excess adiposity and other metabolic complications characteristic of obesity, such as low-grade inflammation and oxidative status. Among them, fungi have gained popularity for their high polysaccharide content and other bioactive components with beneficial activities. Here, we use the C. elegans model to investigate the potential activities of a Grifola frondosa extract (GE), together with the underlying mechanisms of action. Our study revealed that GE represents an important source of polysaccharides and phenolic compounds with in vitro antioxidant activity. Treatment with our GE extract, which was found to be nongenotoxic through a SOS/umu test, significantly reduced the fat content of C. elegans, decreased the production of intracellular ROS and aging-lipofuscin pigment, and increased the lifespan of nematodes. Gene expression and mutant analyses demonstrated that the in vivo anti-obesity and antioxidant activities of GE were mediated through the daf-2/daf-16 and skn-1/nrf-2 signalling pathways, respectively. Taken together, our results suggest that our GE extract could be considered a potential functional ingredient for the prevention of obesity-related disturbances.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Proteínas de Ligação a DNA/metabolismo , Suplementos Nutricionais , Fatores de Transcrição Forkhead/metabolismo , Grifola , Longevidade , Fatores de Transcrição/metabolismo , Tecido Adiposo/metabolismo , Envelhecimento , Animais , Fármacos Antiobesidade/farmacologia , Antioxidantes/farmacologia , Misturas Complexas/farmacologia , Lipofuscina/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
The bioactivity and gelling properties of a carbohydrate-rich algal extract obtained from locally harvested Ascophyllum nodosum seaweed using a chemical-free approach were investigated for its potential interest in food applications. Physicochemical characterisation and compositional analysis of the extract, using FTIR, biochemical methods and monosaccharide analysis, confirmed the presence of alginates and fucoidans, although the main polysaccharide present in it was laminarin. Significant amounts of phenolic compounds (~9 âmg phloroglucinol/100 âmg sample) were also detected. As a result, the extract exhibited good antioxidant activity. It also showed promising prebiotic potential, promoting the growth of beneficial Lactobacillus sp. and Bifidobacteria sp. when compared with commercial prebiotics, but not that of pathogenic bacteria such as E. coli or P. aeruginosa. The gelling properties of the raw extract were explored to optimize hydrogel bead formation by external gelation in CaCl2 solutions. This was enhanced at neutral to alkaline pHs and high extract and CaCl2 concentrations. The mechanical strength, nano- and microstructure of the hydrogel beads prepared under optimised conditions were determined using compression tests, synchrotron small- and wide-angle X-ray scattering (SAXS/WAXS) and scanning electron microscopy (SEM). It was concluded that the raw algal extract at neutral pH had potential for use as a gelling agent, although further enrichment with alginate improved the mechanical properties of the obtained gels. The advantages and disadvantages of applying the non-purified algal extract in comparison with purified carbohydrates are discussed.
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In this work, a bioactive persimmon extract was produced from discarded fruits. A central composite design was used to evaluate the effect of different extraction parameters and ripeness stages of persimmon fruits on the total phenolic content and antioxidant activity of the resulting extracts. Significantly greater phenolic contents were obtained from immature persimmon (IP) fruits. The optimum IP extract with the conditions set by the experimental design was industrially up-scaled and its composition and functional properties were evaluated and compared with those obtained under lab-scale conditions. Both extracts contained significant protein (>20%) and phenolic contents (â¼11-27 mg GA/g dry extract) and displayed significant antiviral activity against murine norovirus and hepatitis A virus. Moreover, the extract showed no toxicity and significantly reduced the fat content and the cellular ageing of Caenorhabditis elegans (C. elegans) without affecting the worm development. These effects were mediated by down-regulation of fat-7, suggesting an anti-lipogenic activity of this extract.
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Diospyros/química , Manipulação de Alimentos/métodos , Fenóis/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Resíduos/análise , Animais , Antioxidantes/química , Antivirais/química , Caenorhabditis elegans , Modelos Animais de Doenças , Camundongos , Norovirus/efeitos dos fármacos , Proteínas/químicaRESUMO
Watermelon is the second largest fruit crop worldwide, with great potential to valorise its rind waste. An experimental design was used to model how extraction parameters (temperature, pH, and time) impact on the efficiency of the process, purity, esterification degree, monosaccharide composition and molar mass of watermelon rind pectin (WRP), with an insight on changes in their structural properties (linearity, branching degree and extraction severity). The models for all responses were accurately fitted (R2 > 90%, lack of fit p ≥ 0.05) and experimentally validated. At optimum yield conditions, WRP yield (13.4%), purity (540 µg/g galacturonic acid) and molar mass (106.1 kDa) were comparable to traditional pectin sources but showed a higher branching degree with longer galactan side chains and a higher protein interaction. Harsher conditions (pH 1) generated purer homogalacturonan fractions with average molar masses (80 kDa) at the expense of yield, while mild extraction conditions (pH ≥ 2) produced highly branched entangled pectin structures. This study underlines novel compositional features in WRP and the possibility of producing novel customized pectin ingredients with a wider potential application scope depending on the targeted structure.
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In the last decades, berries have been identified as important vehicles for the transmission of foodborne viruses and different strategies are being explored to eliminate or reduce viral contamination in these fruits. The aim of this work was to develop novel edible coatings with antiviral properties for inactivating and reducing murine norovirus (MNV). Firstly, the effect of gelatin (G) addition on Persian gum (PG) films was studied in terms of microstructural, mechanical, optical, and water barrier properties. The following PG:G ratios were considered: 100:0, 75:25, 50:50, 25:75, and 0:100. Microstructure analysis revealed the compatibility of both hydrocolloids since no phase separation was observed. The addition of G to PG films provided stiffer and more deformable films than pure PG, with lower water vapor permeability values. Specifically, films prepared with 50:50 PG:G ratio presented better mechanical and barrier performance. Interestingly, pure PG showed antiviral activity on murine norovirus, probably due to the presence of some impurities (mainly tannins). Adding allyl isothiocyanate (AITC) enhanced the PG antiviral activity at refrigerated temperatures in blueberries, not being affected by the AITC concentration. This effect was not observed at ambient temperature, probably due to the volatilization of AITC.