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1.
Int J Mol Sci ; 25(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38542112

RESUMO

The function of immune complexes in rheumatoid arthritis (RA) is related to their composition and size. Using dynamic light scattering (DLS), we investigated the link between the RA circulating immune complex (CIC) particles' size and the CIC immunoglobulin level. In this study, 30 RA patients and 30 healthy individuals were included. IgA, IgG, and IgM were found in all analyzed CICs, but more IgA and IgG were found in RA than in control CICs. In both control and RA CICs, DLS detected 50 particles that differed in size and clustered around two size groups: with a 7.5-164 nm radius and with a 342-1718 nm radius. An increased level of IgA in RA CICs, compared to control ones, was associated with more than 50% of CIC particles. In RA, compared to the control, a higher number of CICs with 28.2 nm, 531 nm, 712 nm, and 1718 nm particles and a lower number of CICs with 78.8 nm particles were detected. This particle distribution pattern did not reflect the changes in the CIC immunoglobulin level. Thus, RA elevated CIC IgA was linked with all these particles (except the 1718 nm particle), the IgM increase was linked with 43.8 nm and 712 nm particles, and the IgG increase was linked with the 712 nm particle only. This study provides the very first data on the association between CIC particles' size, CIC immunoglobulin level, and RA. It opens the possibility that the size of CICs determined by DLS can be used as a criterion in RA diagnosis or monitoring after a large-scale study confirmation.


Assuntos
Complexo Antígeno-Anticorpo , Artrite Reumatoide , Humanos , Hidrodinâmica , Imunoglobulina G , Imunoglobulina M , Imunoglobulinas , Imunoglobulina A
2.
Molecules ; 29(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39274875

RESUMO

The recovery of valuable nutritional compounds, like proteins, from waste streams and by-products is a key strategy for enhancing production sustainability and opening up new market potential. This research aimed to use high-intensity ultrasound as an innovative technique to extract the soluble proteins from the pumpkin leaves. The impact of various sonication amplitudes and duration periods on protein yield, functional properties, antioxidant qualities, and structural characteristics, were studied. Utilization of ultrasound technology significantly increased the yield of pumpkin leaf protein by up to 40%-six times higher than maceration. The ultrasound extraction provided a RuBisCO-rich protein fraction with high radical scavenging and chelating activities, especially at 40% amplitude. Cavitation modified the tertiary and secondary structures of leaf proteins: the amount of α-helix changed based on amplitude (12.3-37.7%), the amount of random coil increased to 20.4%, and the amount of ß-turn reduced from 31 to 18.6%. The alteration of the protein fluorescence spectrum (blue shift in spectrum) provides further evidence that ultrasound alters the proteins' molecular structure in comparation with maceration; the maximum tryptophan fluorescence intensity decreased from 22.000 to 17.096. The hydrophobicity values of 76.8-101.5 were substantially higher than the maceration value of 53.4, indicating that ultrasound improved the hydrophobicity of protein surfaces. Ultrasound resulted in a significant increase in solubility in an acidic environment with the increase in sonication amplitude. A 2.4-fold increase in solubility at pH 2 becomes apparent (20% amplitude; 43.1%) versus maceration (18.2%). The emulsifying ability decreases from 6.62 to 5.13 m2/g once the sonication amplitude increases by 20-70%. By combining the ultrasound periods and amplitudes, it is possible to create high-value protein leaf extracts with improved properties which can find real application as food additives and dietary supplements.


Assuntos
Cucurbita , Química Verde , Folhas de Planta , Proteínas de Plantas , Cucurbita/química , Folhas de Planta/química , Proteínas de Plantas/química , Antioxidantes/química , Ondas Ultrassônicas , Sonicação/métodos , Interações Hidrofóbicas e Hidrofílicas
3.
Anal Biochem ; 674: 115194, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37279816

RESUMO

The size of circulating immune complexes (CICs) in rheumatoid arthritis (RA) could be an emerging criterion in disease diagnosis. This study analyzed size and electrokinetic potential of CICs from RA patients, healthy young adults, and RA patients age-matched controls aiming to establish their unique CIC features. Pooled CIC of 30 RA patients, 30 young adults, and 30 RA group's age-matched controls (middle-aged and oldеr healthy adults), and in vitro IgG aggregates from pooled sera of 300 healthy volunteers were tested using dynamic light scattering (DLS). Size distribution of CIC in healthy young adults exhibited high polydispersity. RA CIC patients and their age-matched control showed distinctly narrower size distributions compared with young adults. In these groups, particles clustered around two well-defined peaks. Particles of peak 1 were 36.1 ± 6.8 nm in RA age-matched control, and 30.8 ± 4.2 nm in RA patients. Particles of peak 2 of the RA age-matched control's CIC was 251.7 ± 41.2 nm, while RA CIC contained larger particles (359.9 ± 50.5 nm). The lower zeta potential of RA CIC, compared to control, indicated a disease-related decrease in colloidal stability. DLS identified RA-specific, but also age-specific distribution of CIC size and opened possibility of becoming a method for CIC size analysis in IC-mediated diseases.


Assuntos
Complexo Antígeno-Anticorpo , Artrite Reumatoide , Pessoa de Meia-Idade , Adulto Jovem , Humanos , Idoso , Difusão Dinâmica da Luz
4.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203164

RESUMO

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drugs in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration and heat-, ultrasound-, and microwave-assisted extractions. Higher total powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher total powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation was distinguished from the others by a higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process mainly affected the position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray-dried formulations compared to freeze-dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and a higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder.


Assuntos
Gelatina/química , Extratos Vegetais/química , Thymus (Planta)/química , Liofilização , Secagem por Atomização
5.
J Microencapsul ; 36(2): 109-119, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30982381

RESUMO

Aim: The aim was to choose the optimal encapsulation system and to incorporate encapsulates loaded with essential oil into the ice cream as a model food product. Methods: Ca-alginate beads were produced by electrostatic extrusion process. Gelatine/alginate coacervates were processed with coacervation. Carnauba wax microparticles were produced using melt dispersion process. Morphological properties, chemical, and thermal stabilities of encapsulates were tested by SEM, FTIR spectral, and thermogravimetric analysis. Results: Alginate provided sufficient emulsion stability over 1 h. Ca-alginate showed higher encapsulation efficiency (EE) (98.4 ± 4.3%) compared to carnauba wax (94.2 ± 7.8%) and gelatine/alginate coacervates (13.2 ± 1.2%). The presence of essential oil in all three types of encapsulates confirmed with FTIR. The encapsulation process ensured controlled release and thermal stability of the oil. Conclusions: Ca-alginate matrix as the most suitable for peppermint essential oil encapsulation. The sensory analysis showed that ice cream incorporating encapsulates is a promising system for the consumption of health beneficial peppermint essential oil.


Assuntos
Aditivos Alimentares/química , Mentha piperita/química , Óleos Voláteis/química , Óleos de Plantas/química , Alginatos/química , Composição de Medicamentos , Emulsões/química , Aditivos Alimentares/administração & dosagem , Sorvetes/análise , Óleos Voláteis/administração & dosagem , Óleos de Plantas/administração & dosagem , Ceras/química
6.
J Food Sci Technol ; 55(1): 128-137, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29358803

RESUMO

This study focuses on the influence of operating conditions on Alcalase-catalyzed egg white protein hydrolysis performed in a continuously stirred tank reactor coupled with ultrafiltration module (10 kDa). The permeate flow rate did not significantly affect the degree of hydrolysis (DH), but a significant increase in process productivity was apparent above flow rate of 1.9 cm3 min-1. By contrast, an increase in enzyme/substrate (E/S) ratio provided an increase in DH, but a negative correlation was observed between E/S ratio and productivity. The relationship between operating conditions and antioxidant properties of the hydrolysates, measured by three methods, was studied using Box-Behnken experimental design and response surface methodology. The statistical analysis showed that each variable (impeller speed, E/S ratio, and permeate flow rate) had a significant effect on the antioxidant capacity of all tested systems. Nevertheless, obtained response functions revealed that antioxidative activity measured by DPPH, ABTS and FRAP methods were affected differently by the same operating conditions. High impeller speeds and low permeate flow rates favor ABTS while high impeller speeds and high permeate flow rates had a positive effect on the DPPH scavenging activity. On the other hand, the best results obtained with FRAP method were achieved under moderate operating conditions. The integration of the reaction and ultrafiltration membrane separation in a continuous manner appears to be a right approach to improve and intensify the enzymatic process, enabling the production of peptides with desired antioxidant activity.

7.
Bioprocess Biosyst Eng ; 40(11): 1713-1723, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28801712

RESUMO

In this study, alcalase (protease from Bacillus licheniformis) immobilization by adsorption, enzyme crosslinking and covalent enzyme binding to activated chitosan microbeads were examined. The biocatalysts highest activity was obtained by covalent immobilization of alcalase onto a solid support. The alcalase covalent immobilization onto different types of chitosan beads obtained by inverse emulsion technique and electrostatic extrusion was studied. Parameters examined under different conditions were beads diameter, enzyme loading, enzyme capacity yield, and biocatalyst activity. The highest activity and enzyme loading of 23.6 IU/mg protein and 340.2 mg/g, respectively, were achieved by the enzyme immobilized onto chitosan microbeads obtained by the electrostatic extrusion technique. FT-IR analysis was used to confirm formation of alcalase-chitosan conjugates. The activity of optimally produced alcalase-chitosan microbeads was then verified in the industrially feasible reaction systems of egg white and soy protein hydrolysis. The high degree of hydrolysis of 29.85 ± 0.967% after 180 min and five successive reuses obtained under real conditions (50 °C, pH 8) verified the covalently bound alcalase to chitosan beads a promising candidate for use in industrial egg white protein hydrolysis process.


Assuntos
Quitosana/metabolismo , Subtilisinas/metabolismo , Biocatálise , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
8.
J Microencapsul ; 34(5): 475-487, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28715926

RESUMO

Black soybean coat is insufficiently valorised food production waste rich in anthocyanins. The goal of the study was to examine physicochemical properties of spray dried extract of black soybean coat in regard to carrier materials: maltodextrin, gum Arabic, and skimmed milk powder. Maltodextrin and gum Arabic-based microparticles were spherical and non-porous while skimmed milk powder-based were irregularly shaped. Low water activity of microparticles (0.31-0.33), good powders characteristics, high solubility (80.3-94.3%) and encapsulation yields (63.7-77.0%) were determined. All microparticles exhibited significant antioxidant capacity (243-386 µmolTE/g), good colour stability after three months of storage and antimicrobial activity. High content of total anthocyanins, with cyanidin-3-glucoside as predominant, were achieved. In vitro release of anthocyanins from microparticles was sustained, particularly from gum Arabic-based. These findings suggest that proposed simple eco-friendly extraction and microencapsulation procedures could serve as valuable tools for valorisation and conversion of black soybean coat into highly functional and stable food colourant.


Assuntos
Composição de Medicamentos , Glycine max/química , Goma Arábica/química , Leite/química , Polissacarídeos/química , Animais , Antocianinas/química , Antioxidantes/química , Sementes/química
9.
J Food Sci Technol ; 54(11): 3411-3420, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29051636

RESUMO

The goal of this study was to investigate the characteristics of grape skin extract (GSE) spray dried with different carriers: maltodextrin (MD), gum Arabic (GA) and skim milk powder (SMP). The grape skin extract was obtained from winery by-product of red grape variety Prokupac (Vitis vinifera L.). The morphology of the powders, their thermal, chemical and physical properties (water activity, bulk and tapped densities, solubility), as well as release studies in different pH conditions were analyzed. Total anthocyanin content and total phenolic content were determined by spectrophotometric methods. MD and GA-based microparticles were non-porous and spherical, while SMP-based ones were irregularly shaped. The process of spray drying Prokupac GSE using these three carriers produced powders with low water activity (0.24-0.28), good powder characteristics, high yields, and solubility higher than 90%. The obtained dissolution/release profiles indicated prolonged release of anthocyanins and phenolic compounds in different mediums, especially from GSE/GA microparticles. These results have shown that grape skin as the main by-product of wine production could be used as a source of natural colorants and bioactive compounds, and microencapsulation as a promising technique for the protection of these compounds, their stabilization in longer periods and prolonged release.

10.
Chemphyschem ; 17(2): 317-24, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26541507

RESUMO

Noncovalent interactions of cis- and trans-2-butene, as the smallest model systems of molecules with cis and trans double bonds, were studied to find potential differences in interactions of these molecules. The study was performed using quantum chemical methods including very accurate CCSD(T)/CBS method. We studied parallel and displaced parallel interactions in 2-butene dimers, in butane dimers, and between 2-butene and saturated butane. The results show the trend that interactions of 2-butene with butane are the strongest, followed by interactions in butane dimers, whereas the interaction in 2-butene dimers are the weakest. The strongest calculated interaction energy is between trans-2-butene and butane, with a CCSD(T)/CBS energy of -2.80 kcal mol(-1) . Interactions in cis-2-butene dimers are stronger than interactions in trans-2-butene dimers. Interestingly, some of the interactions involving 2-butene are as strong as interactions in a benzene dimer. These insights into interactions of cis- and trans-2-butene can improve understanding of the properties and processes that involve molecules with cis and trans double bonds, such as fatty acids and polymers.

11.
Yeast ; 32(1): 271-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25418076

RESUMO

The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 °C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602 g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212.


Assuntos
Rubus/microbiologia , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Ácido Acético/análise , Ácido Acético/metabolismo , Células Imobilizadas/química , Células Imobilizadas/metabolismo , Etanol/análise , Etanol/metabolismo , Fermentação , Humanos , Saccharomyces cerevisiae/química , Paladar , Vinho/análise
12.
Foods ; 13(10)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38790876

RESUMO

Nanofibers made of natural proteins have caught the increasing attention of food scientists because of their edibility, renewability, and possibility for various applications. The objective of this study was to prepare nanofibers based on pumpkin leaf protein concentrate (LPC) as a by-product from some crops and gelatin as carriers for vitamin B12 using the electrospinning technique. The starting mixtures were analyzed in terms of viscosity, density, surface tension, and electrical conductivity. Scanning electron micrographs of the obtained nanofibers showed a slight increase in fiber average diameter with the addition of LPC and vitamin B12 (~81 nm to 109 nm). Fourier transform infrared spectroscopy verified the physical blending of gelatin and LPC without phase separation. Thermal analysis showed the fibers had good thermal stability up to 220 °C, highlighting their potential for food applications, regardless of the thermal processing. Additionally, the newly developed fibers have good storage stability, as detected by low water activity values ranging from 0.336 to 0.376. Finally, the release study illustrates the promising sustained release of vitamin B12 from gelatin-LPC nanofibers, mainly governed by the Fickian diffusion mechanism. The obtained results implied the potential of these nanofibers in the development of functional food products with improved nutritional profiles.

13.
Pharmaceutics ; 16(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38931922

RESUMO

Silibinin has considerable therapeutic potential for the treatment of diabetes through anti-inflammatory, antioxidant, and immunomodulatory properties. However, the therapeutic application of silibinin is quite limited due to its poor bioavailability. In the present study, an attempt was made to improve the antidiabetic efficacy of silibinin by its encapsulation in liposomal vesicles. The liposomes with a high encapsulation efficiency of silibinin (96%) and a zeta potential of -26.2 ± 0.6 mV were developed and studied using nicotinamide/streptozotocin-induced diabetic rats. Administration of silibinin-loaded liposomes to diabetic rats lowered glucose levels, increased insulin levels, and improved pancreatic islet architecture. The anti-inflammatory effect of silibinin-loaded liposomes was demonstrated by a decrease in serum C-reactive protein (CRP) levels and a reduced deposition of collagen fibers in the islets of diabetic rats. Furthermore, silibinin-loaded liposomes were more efficient in lowering glucose, alanine transaminase, triglyceride, and creatinine levels in diabetic rats than pure silibinin. In addition, silibinin-loaded liposomes had a significantly better effect on beta-cell mass and Glut2 glucose receptor distribution in diabetic islets than pure silibinin. The present results clearly show that liposome encapsulation of silibinin enhances its antidiabetic efficacy, which may contribute to the therapeutic benefit of silibinin in the treatment of diabetes and its complications.

14.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675478

RESUMO

Without being aware of their chemical composition, many cultures have used herbaceous peony roots for medicinal purposes. Modern phytopreparations intended for use in human therapy require specific knowledge about the chemistry of peony roots and their biological activities. In this study, ethanol-water extracts were prepared by maceration and microwave- and ultrasound-assisted extractions (MAE and UAE, respectively) in order to obtain bioactive molecules from the roots of Paeonia tenuifolia L., Paeonia peregrina Mill., and Paeonia officinalis L. wild growing in Serbia. Chemical characterization; polyphenol and flavonoid content; antioxidant, multianti-enzymatic, and antibacterial activities of extracts; and in vitro gastrointestinal digestion (GID) of hot water extracts were performed. The strongest anti-cholinesterase activity was observed in PT extracts. The highest anti-ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical potential was observed in PP extracts, whereas against DPPH (2,2-diphenyl-1-picrylhydrazyl radicals), the best results were achieved with PO extracts. Regarding antibacterial activity, extracts were strongly potent against Bacillus cereus. A molecular docking simulation was conducted to gather insights into the binding affinity and interactions of polyphenols and other Paeonia-specific molecules in the active sites of tested enzymes. In vitro GID of Paeonia teas showed a different recovery and behavior of the individual bioactives, with an increased recovery of methyl gallate and digallate and a decreased recovery of paeoniflorin and its derivatives. PT (Gulenovci) and PP (Pirot) extracts obtained by UAE and M were more efficient in the majority of the bioactivity assays. This study represents an initial step toward the possible application of Paeonia root extracts in pharmacy, medicine, and food technologies.

15.
Appl Microbiol Biotechnol ; 97(21): 9397-407, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23995224

RESUMO

The rising trend of bioflavour synthesis by microorganisms is hindered by the high manufacturing costs, partially attributed to the cost of the starting material. To overcome this limitation, in the present study, dilute-acid hydrolysate of orange peel was employed as a low-cost, rich in fermentable sugars substrate for the production of flavour-active compounds by Saccharomyces cerevisiae. With this purpose, the use of immobilized cell technology to protect cells against the various inhibitory compounds present in the hydrolysate was evaluated with regard to yeast viability, carbon and nitrogen consumption and cell ability to produce flavour active compounds. For cell immobilization the encapsulation in Ca alginate beads was used. The results were compared with those obtained using free-cell system. Based on the data obtained immobilized cells showed better growth performance and increased ability for de novo synthesis of volatile esters of "fruity" aroma (phenylethyl acetate, ethyl hexanoate, octanoate, decanoate and dodecanoate) than those of free cells. The potential for in situ production of new formulations containing flavour-active compounds derive from yeast cells and also from essential oil of orange peel (limonene, α-terpineol) was demonstrated by the fact that bioflavour mixture was found to accumulate within the beads. Furthermore, the ability of the immobilized yeast to perform efficiently repeated batch fermentations of orange peel hydrolysate for bioflavour production was successfully maintained after six consecutive cycles of a total period of 240 h.


Assuntos
Células Imobilizadas/metabolismo , Citrus sinensis/metabolismo , Aromatizantes/metabolismo , Resíduos Industriais , Saccharomyces cerevisiae/metabolismo , Carbono/metabolismo , Hidrólise , Viabilidade Microbiana/efeitos dos fármacos , Nitrogênio/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia
16.
Pharmaceutics ; 15(12)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38140083

RESUMO

Paeonia tenuifolia L. (steppe peony) petal extract was proficiently encapsulated into liposomes and biopolymer films in the current work, both times utilizing a single-step procedure. The encapsulation efficiency, size of the particles, and index of polydispersity (PDI), as well as the ζ potential of the obtained liposomes were determined, whereas in the case of films, the test included moisture content and mechanical property assessment. Fourier transform infrared spectroscopy (FT-IR) was used to evaluate the chemical composition and existence of numerous interactions in the systems. All the obtained encapsulates were subjected to antibacterial, antifungal and antibiofilm activity testing of the pathogens associated with human skin. The results indicated that the liposomes prepared using Phospholipon had the highest encapsulation efficiency (72.04%), making them the most favorable ones in the release study as well. The biological assays also revealed that Phospholipon was the most beneficial phospholipid mixture for the preparation of liposomes, whereas the film containing these liposomes did not have the ability to inhibit pathogen growth, making the double encapsulation of P. tenuifolia L. petal extract needless. These findings may be a first step toward the potential use of steppe peony extract-loaded films and liposomes in pharmaceutical and cosmetical industries.

17.
J Sci Food Agric ; 92(3): 685-96, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21953367

RESUMO

BACKGROUND: Encapsulation of Thymus serpyllum L. aqueous extract within calcium alginate beads was studied in order to produce dosage formulations containing polyphenolic compounds. Electrostatic extrusion was applied for encapsulation of thyme aqueous extract in alginate gel beads. In addition to hydrogel beads, heat-dried and freeze-dried forms of beads were examined. METHODS: Encapsulation systems were examined and compared in order to choose the optimal one with respect to entrapment efficiency, preservation of antioxidant activity and thermal behaviour under heating conditions simulating the usual food processing. RESULTS: The beads obtained with approximately 2 mg g⁻¹ of gallic acid equivalents encapsulated in 0.015 g mL⁻¹ of alginate were spheres of a uniform size of about 730 µm. Encapsulation efficiency varied in the range 50-80% depending on the encapsulation method. Besides, the analysis reveals that the encapsulation process and the material used did not degrade the bioactive compounds, as the total antioxidant content remained unchanged. This was verified by Fourier transform infrared analysis, which proved the absence of chemical interactions between extracted compounds and alginate. Addition of a filler substance, such as sucrose and inulin, in the dried product reduced its collapse and roundness distortion during drying process. CONCLUSION: This study demonstrates the potential of using hydrogel material for encapsulation of plant poplyphenols to improve their functionality and stability in food products.


Assuntos
Alginatos/química , Antioxidantes/química , Suplementos Nutricionais , Tecnologia de Alimentos , Alimentos Fortificados , Extratos Vegetais/química , Thymus (Planta)/química , Sacarose Alimentar/química , Conservantes de Alimentos/análise , Conservantes de Alimentos/química , Liofilização , Géis , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Temperatura Alta , Hidrogéis , Inulina/química , Microesferas , Tamanho da Partícula , Sérvia , Espectroscopia de Infravermelho com Transformada de Fourier , Especiarias/análise , Eletricidade Estática
18.
Food Chem X ; 15: 100370, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-35782959

RESUMO

This study presents the state-of-art research about the assembly of soy proteins in nanocarriers, liposomes, and its design includes different physicochemical strategies and approaches: two-step enzymatic hydrolysis of soy concentrate, hydrolysate encapsulation by using phospholipids and cholesterol, and application of ultrasonication. Achieved results revealed that ultrasonication, together with cholesterol addition into phospholipid layers, improved the stability of nanoliposomes, and a maximum EE value of 60.5 % was obtained. Average size of peptide-loaded nanoliposomes was found to be from 191.1 to 286.7 nm, with a ζ potential of -25.5 to -34.6 mV, and a polydispersity index of 0.250-0.390. Ultrasound-assisted encapsulation process did not lead to a decrease in the antioxidant activity of the trapped peptides. FTIR has indicated an effective hydrophobic interaction between phosphatidylcholine and hydrolysate peptides. TEM and SEM have confirmed the spherical nanocarrier structure and unilamelarity. Prolonged gastrointestinal release and stability of peptides have been enabled by liposome nanocarriers.

19.
Polymers (Basel) ; 14(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35808660

RESUMO

The aim of this study was to investigate covalent immobilization of horseradish peroxidase (HRP) on magnetic nanoparticles (Mag) encapsulated in calcium alginate beads (MABs) for color degradation, combining easy and fast removal of biocatalyst from the reaction mixture due to its magnetic properties and strong binding due to surface alginate functional groups. MABs obtained by extrusion techniques were analyzed by optical microscopy, FEG-SEM and characterized regarding mechanical properties, magnetization and HRP binding. HRP with initial concentration of 10 mg/gcarrier was successfully covalently bonded on MABs (diameter ~1 mm, magnetite/alginate ratio 1:4), with protein loading of 8.9 mg/gcarrier, immobilization yield 96.9% and activity 32.8 U/g. Immobilized HRP on MABs (HRP-MABs) was then used to catalyze degradation of two anthraquinonic dyes, Acid Blue 225 (AB225) and Acid Violet 109 (AV109), as models for wastewater pollutants. HRP-MABs decolorized 77.3% and 76.1% of AV109 and AB225, respectively after 15 min under optimal conditions (0.097 mM H2O2, 200 mg of HRP-MABs (8.9 mg/gcarrier), 0.08 and 0.1 g/mg beads/dye ratio for AV109 and AB225, respectively). Biocatalyst was used for 7 repeated cycles retaining 75% and 51% of initial activity for AB225 and AV109, respectively, showing potential for use in large scale applications for colored wastewater treatment.

20.
Pharmaceuticals (Basel) ; 15(12)2022 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-36558988

RESUMO

Without being aware of its chemical makeup, many ancient societies have used Steppe peony in their traditional medicine. Given that modern phytopreparation intended for use on human skin requires, above all, knowledge of its chemical composition, the goal of this study was to make a screening of the composition of aqueous and methanolic extracts of the petals of P. tenuifolia L. and to examine them for various skin-beneficial properties. The extracts were prepared by maceration, ultrasound-assisted, and microwave-assisted extraction procedures. The chemical profiling was conducted by the use of UHPLC-LTQ-OrbiTrap MS and UHPLC/MS, and spectrophotometric methods for the determination of total polyphenol and total flavonoid contents. The biological activities entailed antioxidant ABTS, DPPH, CUPRAC (Cupric Ion Reducing Antioxidant Capacity), and FRAP (Ferric Reducing Antioxidant Power) assays, antimicrobial (antibacterial and antifungal) and antibiofilm activities, cytotoxicity, wound healing potential, as well as the adhesion and invasion of Staphylococcus lugdunensis. The results showed that the petals are rich in phenolic acids and flavonoids, which are commonly associated with numerous biological activities. The aqueous extracts were more efficient in the majority of the bioactivity assays then the methanolic ones, whereas the optimal extraction method varied between the assays. This study is the first step towards the safe use of the aqueous extracts of P. tenuifolia petals for therapeutic skin treatments.

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