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1.
Food Chem ; 352: 129319, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33691215

RESUMO

Emulsions based on licorice essential oil (LEO) were prepared under different homogenization conditions (ultra-homogenization (U1) or U1 together with sonication (U2)). The obtained emulsions were incorporated into the carboxymethyl cellulose (CMC) film. The results showed that U2 caused significant changes in the size and the surface charge of the emulsions. Remarkable differences in the microstructure were observed between the U1 and the U2 emulsion-based films as revealed by SEM and AFM. Both emulsions reduced the rigidity and increased the flexibility of the films. The film made from the CMC alone had a water vapor permeability (WVP) of 2.66 × 10-9 g m-1 s-1 Pa-1, while the CMC film made from U2 emulsion had a WVP of 1.87 × 10-9 g m-1 s-1 Pa-1. Also, the film containing 0.0125% U1-LEO exhibited antibacterial activity on gram-positive bacteria only while the film containing 0.0125% U2-LEO demonstrated antibacterial activity on both gram-positive and gram-negative bacteria.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Glycyrrhiza/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Sonicação , Carboximetilcelulose Sódica/química , Emulsões , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Permeabilidade , Vapor
2.
Food Chem ; 350: 129249, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33610840

RESUMO

This study investigated the effect of ultrasonic treatments on the properties and stability of the water-in-oil (W/O) emulsion of Pulicaria jaubertii (PJ) extract. The study used different ultrasound powers (0, 100, 200, 400, and 600 W) at two storage degrees (4 and 25 °C) for 28 days. The findings showed that the emulsifying properties were improved to different extents after ultrasonic treatments. The treatment at 600 W showed optimum particle size, polydispersity index, emulsifying property, viscosity properties, and release of total phenolic content than the other powers. However, the ultrasonic power of 400 W gave positive effects on creaming index and antioxidant release compared to 600 W. The emulsion stored at 4 °C presented higher stability than that stored at 25 °C during the 28 days of storage. Microscopically, the increase in sonication power up to 600 W reduced particle size and decreased flocculation, thus resulted in stable emulsions, which is desirable for its applications in food systems.


Assuntos
Óleos/química , Extratos Vegetais/química , Pulicaria/química , Sonicação , Água/química , Antioxidantes/análise , Emulsões , Tamanho da Partícula , Viscosidade
3.
Food Chem ; 348: 129132, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33524691

RESUMO

Enzymatic browning is considered a critical factor that adversely decreases the quality of fresh-cut products. Although many individual physical or chemical methods have been explored to control browning, there are few approaches combining these technologies. In the present study, Sonchus oleraceus L. extract (SOLE) and ultrasound treatment efficiently controlled the activities of polyphenol oxidase, peroxidase, phenylalanine ammonia-lyase, lipoxygenase, soluble quinones, and intermediate and advanced products, and a lower malondialdehyde content and higher antioxidant capacity were observed in fresh-cut potato slices. More than 50 phenolics and flavonoids were identified in SOLE by liquid chromatography-tandem mass spectrometry. In conclusion, the combined SOLE and ultrasound treatment could serve as a promising method for attenuating enzymatic browning.


Assuntos
Extratos Vegetais/química , Solanum tuberosum/química , Sonchus/química , Sonicação , Antioxidantes/química , Catecol Oxidase/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Reação de Maillard , Malondialdeído/metabolismo , Fenóis/análise , Fenilalanina Amônia-Liase/metabolismo , Solanum tuberosum/metabolismo , Sonchus/metabolismo , Espectrometria de Massas em Tandem
4.
Int J Nanomedicine ; 16: 925-939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603360

RESUMO

Background: Antimicrobial resistance poses substantial risks to human health. Thus, there is an urgent need for novel antimicrobial agents, including alternative compounds, such as peptides derived from bacterial toxin-antitoxin (TA) systems. ParELC3 is a synthetic peptide derived from the ParE toxin reported to be a good inhibitor of bacterial topoisomerases and is therefore a potential antibacterial agent. However, ParELC3 is inactive against bacteria due to its inability to cross the bacterial membranes. To circumvent this limitation we prepared and used rhamnolipid-based liposomes to carry and facilitate the passage of ParELC3 through the bacterial membrane to reach its intracellular target - the topoisomerases. Methods and Results: Small unilamellar liposome vesicles were prepared by sonication from three formulations that included 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and cholesterol. ParELC3 was loaded with high efficiency into the liposomes. Characterization by DLS and TEM revealed the appropriate size, zeta potential, polydispersity index, and morphology. In vitro microbiological experiments showed that ParELC3 loaded-liposomes are more efficient (29 to 11 µmol·L-1) compared to the free peptide (>100 µmol·L-1) at inhibiting the growth of standard E. coli and S. aureus strains. RL liposomes showed high hemolytic activity but when prepared with POPC and Chol this activity had a significant reduction. Independently of the formulation, the vesicles had no detectable cytotoxicity to HepG2 cells, even at the highest concentrations tested (1.3 mmol·L-1 and 50 µmol·L-1 for rhamnolipid and ParELC3, respectively). Conclusion: The present findings suggest the potential use of rhamnolipid-based liposomes as nanocarrier systems to enhance the bioactivity of peptides.


Assuntos
Antibacterianos/farmacologia , Portadores de Fármacos/química , Glicolipídeos/química , Nanopartículas/química , Peptídeos/farmacologia , Sistemas Toxina-Antitoxina , Sequência de Aminoácidos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Células Hep G2 , Humanos , Hidrodinâmica , Lipossomos , Testes de Sensibilidade Microbiana , Peptídeos/química , Sonicação , Staphylococcus aureus/efeitos dos fármacos
5.
Int J Nanomedicine ; 16: 1005-1019, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603365

RESUMO

Purpose: Development of hyaluronic acid conjugated metformin-phospholipid sonocomplexes (HA-MPS), a biphasic complexation product compiled for enhancing both the lipophilicity and targeting potential of Metformin (MET) to CD44 receptors on pancreatic cancer. Methods: MET was chemically conjugated to hyaluronic acid (HA) via amide coupling reaction. Then, the HA conjugated MET was physically conjugated to Lipoid™S100 via ultrasound irradiation. A combined D-optimal design was implemented to statistically optimize formulation variables. The HA-MPS were characterized through solubility studies, partition coefficient, drug content uniformity, particle size and zeta potential. The optimized HA-MPS was tested via proton nuclear magnetic resonance, infrared spectroscopy to elucidate the nature of physicochemical interactions in the complex which was further scrutinized on molecular level via molecular docking and dynamic simulation. Results: The solubility and partition studies showed a lipophilicity enhancement up to 67 folds as they adopted inverted micelles configuration based on the packing parameter hypothesis. The optimized HA-MPS showed 11.5 folds lower IC50, extra 25% reduction in oxygen consumption rate, better reduction in hypoxia-inducible factor and reactive oxygen species in MiaPaCa-2 cells. Conclusion: These results proved better internalization of MET which was reflected by abolishing hypoxic tumour microenvironment, a mainstay toward a normoxic and less resistant pancreatic cancer.


Assuntos
Ácido Hialurônico/química , Metformina/farmacologia , Fosfolipídeos/química , Sonicação , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , 1-Octanol/química , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glucose/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Concentração Inibidora 50 , Micelas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Consumo de Oxigênio/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Tamanho da Partícula , Espectroscopia de Prótons por Ressonância Magnética , Espécies Reativas de Oxigênio/metabolismo , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Água/química
6.
Food Chem ; 343: 128417, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406574

RESUMO

This study aimed to investigate the structural and antimicrobial properties of Maillard reaction products (MRPs) in chicken liver protein (CLP) and its hydrolysate (CLPH) after sonication (SCLPH). The MRPs of CLP (CLPM), CLPH (CLPHM) and SCLPH (SCLPHM) were analyzed by several spectrometric techniques. The molecular weights of the CLPHM and SCLPHM were primarily between 1.35 kDa and 17 kDa. Moreover, the molecular weights in the CLPHM and SCLPHM below 1.35 kDa were increased, which indicated that cross-linking and thermal degradation occurred during the Maillard reaction (MR). The SCLPHM showed an obvious network skeleton, and the surface had many small crystal-shaped particles after ultrasound treatment and MR by scanning electron microscopy. The SCLPHM had more negative charges than the CLPHM, thus effectively inhibiting the growth of S. saprophyticus and E. coli. MR and ultrasound treatment could be a promising technology to expand the application prospects of low-value meat byproducts.


Assuntos
Antibacterianos/química , Fígado/metabolismo , Hidrolisados de Proteína/química , Animais , Antibacterianos/farmacologia , Galinhas , Escherichia coli/efeitos dos fármacos , Reação de Maillard , Peso Molecular , Hidrolisados de Proteína/farmacologia , Sonicação , Staphylococcus saprophyticus/efeitos dos fármacos , Temperatura de Transição
7.
Methods Mol Biol ; 2261: 563-585, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33421015

RESUMO

This chapter covers the various methods of mechanical cell disruption and tissue homogenization that are currently commercially available for processing small samples s < 1 mL) to larger multikilogram production quantities. These mechanical methods of lysing do not introduce chemicals or enzymes to the system. However, the energies required when using these "harsh," high mechanical energy methods can be enough to damage the very components being sought.The destruction of cell membranes and walls is effected by subjecting the cells (a) to shearing by liquid flow, (b) to exploding by pressure differences between inside and outside of cell, (c) to collision forces by impact of beads or paddles, or (d) a combination of these forces.Practical suggestions to optimize each method, where to acquire such equipment, and links to reference sources are included. Several novel technologies are presented.


Assuntos
Fracionamento Celular/instrumentação , Extratos de Tecidos , Animais , Extratos Celulares , Centrifugação/instrumentação , Desenho de Equipamento , Humanos , Pressão , Sonicação/instrumentação , Estresse Mecânico
8.
Carbohydr Polym ; 256: 117510, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483031

RESUMO

Cellulose nanofibers (CNF) are renewable and biodegradable nanomaterials with attractive barrier, mechanical and surface properties. In this work, three different recombinant enzymes: an endoglucanase, a xylanase and a lytic polysaccharide monooxygenase, were combined to enhance cellulose fibrillation and to produce CNF from sugarcane bagasse (SCB). Prior to the enzymatic catalysis, SCB was chemically pretreated by sodium chlorite and KOH, while defibrillation was accomplished via sonication. We obtained much longer (µm scale length) and more thermostable (resisting up to 260 °C) CNFs as compared to the CNFs prepared by TEMPO-mediated oxidation. Our results showed that a cooperative action of the set of hydrolytic and oxidative enzymes can be used as a "green" treatment prior to the sonication step to produce nanofibrillated cellulose with advanced properties.


Assuntos
Celulase/química , Celulose/química , Endo-1,4-beta-Xilanases/química , Oxigenases de Função Mista/química , Nanofibras/química , Biocatálise , Biodegradação Ambiental , Cloretos/química , Óxidos N-Cíclicos/química , Química Verde , Humanos , Hidrólise , Hidróxidos/química , Nanofibras/ultraestrutura , Oxirredução , Polissacarídeos/química , Compostos de Potássio/química , Saccharum/química , Sonicação
9.
Food Chem ; 347: 128985, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33476920

RESUMO

As the most important tenderness related protein in mammal, there are few studies on how the nanoscale morphology of collagen I in tissues is related to traditional meat processing. The ultrastructure and mechanical characteristics of collagen fibers in tendon with different treatments have been explored in this study. Collagen fibers in homogenate group and acetic acid group were treated with ultrasound and thermal treatment. The nanoscale morphology of collagen fiber in homogenate group became granular at 60 °C and gelatin was formed at 70 °C. The collagen fibers extracted from acetic acid are unstable and easier to break under the same processing parameters, when compared with homogenated collagen fibers in both ultrasound and thermal treatment. The results suggested that acetic acid can disassemble the salt bond and Schiff-base in collagen, and the collagen fibers became loose but the triple helix structure remained integrity.


Assuntos
Colágeno/ultraestrutura , Microscopia de Força Atômica , Tendões/metabolismo , Ácido Acético/química , Animais , Bovinos , Colágeno/química , Bases de Schiff/química , Sonicação , Temperatura
10.
Food Chem ; 347: 129042, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482488

RESUMO

A new method based on graphene oxide modified (4-phenyl) methanethiol nanomagnetic composite (Fe3O4@4-PhMT-GO) was used for extraction and separation of aluminum from wastewater, food, and vegetable samples in aluminum cookware by microwave dispersive magnetic micro solid-phase extraction (MDM-µ-SPE). In optimized conditions, the working range (WR), the linear range (LR), the limit of detection (LOD), and enrichment factor (EF) were obtained 5-5200 µg L-1, 5-1600 µg L-1, 1.5 µg L-1, and 48.8, respectively (RSD% = 2.5). By MDM-µ-SPE procedure, the aluminum concentrations in baking rice and spinach with aluminum cookware were obtained 97.43 ± 2.57 mg g-1 and 131.64 ± 5.18 mg g-1, respectively which was analyzed by atom trap flame atomic absorption spectrometer (AT-FAAS). The results showed, the aluminum concentrations in cooked foods with Teflon cookware were less than aluminum cookware. The methodology was validated by standard reference materials (SRM) and inductively coupled plasma mass spectrometry analysis (ICP-MS).


Assuntos
Alumínio/análise , Análise de Alimentos/métodos , Microextração em Fase Sólida/métodos , Espectrofotometria Atômica , Verduras/química , Águas Residuárias/química , Adsorção , Alumínio/isolamento & purificação , Óxido Ferroso-Férrico/química , Grafite/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Magnetismo , Micro-Ondas , Sonicação , Compostos de Sulfidrila/química
11.
Food Chem ; 347: 129058, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486367

RESUMO

In the present work, a comprehensive phenolic analysis of fresh sugarcane juice from three different harvest seasons was performed and the effect of ohmic heating and ultrasound treatments on the phenolic content and color of the juice was evaluated. Among the 32 phenolic compounds identified, a total of 17 were quantified, comprising, in decreasing order of abundance, flavones (38-49 mg/L), dilignols (22-29 mg/L), and phenolic acid derivatives (17-30 mg/L). The main phenolic groups affected by the crop season (year and season) were flavones and phenolic acid derivatives. Juice treated by ohmic heating and ultrasound showed a total phenolic content similar to fresh juice, indicating the absence of additional non-thermal effects. Regarding color, both treatments promoted only a slight difference by visual perception. Considering these two quality parameters, ultrasound and ohmic heating seem to be a good alternative for sugarcane juice pasteurization.


Assuntos
Sucos de Frutas e Vegetais/análise , Espectrometria de Massas/métodos , Fenóis/análise , Saccharum/química , Cromatografia Líquida de Alta Pressão , Cor , Flavonas/análise , Manipulação de Alimentos , Oxirredução , Pasteurização , Saccharum/metabolismo , Estações do Ano , Sonicação
12.
Food Chem ; 346: 128905, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401085

RESUMO

This study aims to evaluate the effect of ultrasonic pretreatment combined with glycation on the structural characteristics and antibacterial activity of ovotransferrin (OVT). Firstly, OVT (purity >90%) was isolated from egg white with a simple and efficient method. After the treatment of ultrasound and glycation, the browning degree of OVT increased with the rising power of ultrasound, while the number of free amino groups obviously decreased to 25.4%. Various spectrum detection showed that the structures of OVT have changed significantly, indicating the tertiary structure became more flexible and looser. The minimal inhibitory concentration of ultrasound glycated OVT were 25.0 and 32.1 µmol/L for E. coli and S. aureus, respectively. In summary, ultrasound-assisted glycation is an effective technique to improve the biological activity of OVT.


Assuntos
Conalbumina/metabolismo , Sonicação , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Conalbumina/isolamento & purificação , Conalbumina/farmacologia , Clara de Ovo/química , Escherichia coli/efeitos dos fármacos , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Reação de Maillard , Testes de Sensibilidade Microbiana , Estrutura Secundária de Proteína , Staphylococcus aureus/efeitos dos fármacos
13.
ACS Appl Mater Interfaces ; 13(2): 3186-3198, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33398989

RESUMO

Mesoscaled assemblies are organized in native collagen tissues to achieve remarkable and diverse performance and functions. In this work, a facile, low-cost, and controllable liquid exfoliation method was applied to directly extract these collagen mesostructures from bovine Achilles tendons using a sodium hydroxide (NaOH)/urea aqueous system with freeze-thaw cycles and sonication. A series of collagen fibrils with diameters of 26-230 nm were harvested using this process, and in situ observations under polarizing microscopy (POM) and using molecular dynamics simulations revealed the influence of the NaOH/urea system on the tendon collagen. FTIR and XRD results confirmed that these collagen fibrils preserved typical structural characteristics of type I collagen. These isolated collagen fibrils were then utilized as building blocks to fabricate free-standing collagen membranes, which exhibited good stability in solvents and outstanding mechanical properties and transparency, with potential for utility in optical and electronic sensors. Moreover, in vitro and vivo evaluations demonstrated that these new resulting collagen membranes had good cytocompatibility, biocompatibility, and degradability for potential applications in biomedicine. This work provides a new approach for collagen processing by liquid exfoliation with utility for the formation of robust collagen materials that consist of native collagen mesostructures as building blocks.


Assuntos
Tendão do Calcâneo/química , Materiais Biocompatíveis/química , Colágeno/química , Membranas Artificiais , Animais , Bovinos , Linhagem Celular , Colágeno/ultraestrutura , Feminino , Congelamento , Camundongos , Ratos Sprague-Dawley , Hidróxido de Sódio/química , Sonicação , Resistência à Tração , Ureia/química
14.
Environ Sci Pollut Res Int ; 28(11): 14192-14198, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517532

RESUMO

The seemingly ubiquitous presence of plastic debris led to a greater focus on micro- and nanoplastics research derived from the degradation process of macroplastics. The ingestion and consequent accumulation of plastics on the biota are the main concerns. Researchers strive to make assay conditions as close as possible to those of the environment. In this regard, sonication can be applied to de-agglomerate the plastic particles, but this may alter significantly their toxicity. The aim of this study was to understand the effects of the sonication process on the acute toxicity and swimming behavior of polystyrene nanoparticles using Daphnia magna as the test organism. The results show a 2-fold reduction in the acute toxicity after the sonication process; the EC50 of the PSNP-NS was 1.28 ± 0.17 mmol while for PSNP-S the EC50 was 2.77 ± 0.32 mmol, possibly through the formation of an eco-corona on the nanoplastic surface, formed from the ions dispersed in the medium or proteins secreted by the test organisms. The mean swimming distance was reduced when compared to the control group for both the PSNP-S and PSNP-NS. This is the first research stating the toxicological differences between sonicated and non-sonicated polystyrene nanoparticle samples using Daphnia magna as test organism.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Daphnia , Nanopartículas/toxicidade , Poliestirenos , Sonicação , Natação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
15.
J Chromatogr A ; 1636: 461768, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33326928

RESUMO

This work describes an ultrasound-assisted dispersive solid-phase extraction method combined with reversed-phase high-performance liquid chromatography-photodiode array detection (UADSPE-RPLC-PDA) for the determination of nine common biogenic amines (BAs) in canned seafood. The pretreatment extraction solvent, ultrasonic treatment duration, and derivatization conditions were optimized. The method was validated on the basis of the limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy and successfully applied to analyze four canned fish, two canned shrimp and four canned shellfish samples. LODs of 0.08-0.25 mg kg-1 were achieved, and the correlation coefficient of determination was 0.9994-0.9997. The method had high precision and accuracy, with relative standard deviations (RSDs) and recoveries of 0.44 to 6.83% and 72.57 to 99.74%, respectively, suggesting the effectiveness of ultrasound-assisted extraction at increasing the solubility of the target analytes in the solvent system and the feasibility of UADSPE-RPLC-PDA for determining trace BAs in canned seafood.


Assuntos
Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Alimentos Marinhos/análise , Animais , Aminas Biogênicas/isolamento & purificação , Cromatografia de Fase Reversa , Limite de Detecção , Extração em Fase Sólida , Solventes/química , Sonicação
16.
Food Chem ; 334: 127498, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688179

RESUMO

In this work, ultrasound-assisted enzymatic extraction (UAEE) conditions of umami compounds from Labeo rohita head (LRH) was optimised using the combination of fractional factorial design (FFD) and central composite design (CCD). Six factors that can potentially influence the degree of hydrolysis (DH), equivalent umami concentration (EUC), and extraction yield (EY) of umami extract were screened through FFD. The three most significant variables were further optimised using the CCD. The developed models were successfully fitted to the experimental data and used to determine optimal extraction conditions. The optimum DH (22.73%), EUC (6.61 g MSG/100 g protein), and EY (76.34%) of umami extract were achieved with a liquid-solid ratio of 3 (v/w), ultrasonication time of 19.20 min and hydrolysis time of 140.45 min. Besides, UAEE umami extract exhibited higher DH, EUC, EY, and umami taste compared to that of the conventional enzymatic extraction (CEE).


Assuntos
Produtos Pesqueiros/análise , Sonicação , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Cyprinidae , Proteínas de Peixes/metabolismo , Hidrólise , Projetos de Pesquisa
17.
Food Chem ; 334: 127561, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711272

RESUMO

Grapefruit (Citrus paradisi) peel (GP) is rich in flavonoids and phenolics which have several proven pharmacological effects. However, their chemical instability towards oxygen, light and heat limits its applications in food industries. In the present study, we evaluated the feasibility of fabricating grapefruit-peel-phenolic (GPP) nano-emulsion in mustard oil using ultrasonication. Response surface methodology (RSM) optimization revealed that sonication time of 9.5 min at 30% amplitude and 0.52% Span-80 produced the stable GPP nano-emulsion with a droplet size of 29.73 ± 1.62 nm. Results indicate that both ultrasonication and Span-80 can assist the fabrication of a stabilized nano-emulsion. This study is one of its kind where nano-encapsulation of GPP into W/O emulsion was done to stabilize the active compound inside mustard oil and then the nano-emulsion was used to extend oxidative stability of mustard oil. Findings provide a basic guideline to formulate stable nano-emulsions for their use in active food packaging, oils, and pharmaceuticals.


Assuntos
Citrus paradisi/química , Emulsões/química , Mostardeira/química , Nanoestruturas/química , Óleos Vegetais/química , Polifenóis/química , Antioxidantes/química , Armazenamento de Alimentos , Frutas/química , Hexoses/química , Oxirredução , Sonicação
18.
Food Chem ; 338: 128025, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32927200

RESUMO

Short-chain fatty acid esters are important flavor chemicals in Chinese traditional fermented Baijiu. Monascus purpureus was recognized as an important microorganism contributing to ester synthesis. However, the molecular basis for ester synthesis was still lacking. The present work combined genome sequencing, transcriptome sequencing, gene library construction, and enzyme engineering to discover a novel catalyst from M. purpureus (isolated from Baijiu fermentation starter). Enzyme LIP05, belonging to the α/ß hydrolase family, was identified to synthesize short-chain fatty acid esters under aqueous phase. After deleting the lid domain of LIP05, the synthesis of ethyl pentanoate, ethyl hexanoate, ethyl octanoate, or ethyl decanoate was achieved. Ethyl octanoate with the highest conversion ratio of 93.7% was obtained with the assistance of ultrasound. The study reveals the molecular basis for synthesizing short-chain fatty acid esters by M. purpureus and will promote the application of the species or the enzyme in food industry.


Assuntos
Hidrolases/metabolismo , Monascus/genética , Água/química , Vinho/análise , Biocatálise , Caproatos/química , Caproatos/metabolismo , Ésteres/química , Ésteres/metabolismo , Evolução Molecular , Concentração de Íons de Hidrogênio , Hidrolases/genética , Monascus/metabolismo , Sonicação , Temperatura
19.
Carbohydr Polym ; 254: 117271, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357852

RESUMO

Dispersion of cellulose nanocrystals (CNCs) is of utmost importance to guarantee their reliable application. Nevertheless, there is still no consensual method to characterize CNC aggregation. The hypothesis of this paper is that dispersion could be quantified through the classification of aggregates detected in transmission electron microscopy images. k-Means was used to classify image particulate elements of five CNC samples into groups according to their geometric features. Particles were classified into five groups according to their maximum Feret diameter, elongation, circularity and area. Two groups encompassed the most application-critical aggregates: one integrated aggregates of high complexity and low compactness while the other included elongated aggregates. In addition, the characterization of CNC dispersion after different levels of sonication was achieved by assessing the change in the number of elements belonging to each cluster after sonication. This approach could be used as a standard for the characterization of the aggregation state of CNCs.


Assuntos
Celulose/química , Nanopartículas/química , Nanopartículas/ultraestrutura , Materiais Biocompatíveis/química , Celulose/classificação , Fractais , Processamento de Imagem Assistida por Computador , Microscopia Eletrônica de Transmissão , Nanopartículas/classificação , Tamanho da Partícula , Sonicação , Aprendizado de Máquina não Supervisionado
20.
Food Chem ; 345: 128759, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33310251

RESUMO

In this study, pomegranate seed oil (PSO) nanoemulsions loading different amounts of α-tocopherol (0-40%) were produced. The nanoemulsions were fabricated by ultra-sonication method and the influence of thermal treatment (20-90 °C), pH (2-8) and ionic strength (0-500 mM NaCl) were investigated on physicochemical properties of all treatments. Moreover, the oxidative stability and α-tocopherol degradation were also assessed on optimal enriched nanoemulsion formulation during 50-day storage. The droplet diameter, viscosity, antioxidant activity, encapsulation efficiency and loading capacity of optimal formulation were 37.5 nm, 514 cp, 92%, 3.45% and 92.5%, respectively. The peroxide value changed in the range of 4.5-5.3 and 6.7-10.5 meq O2/kg in loaded and unloaded nanoemulsions, respectively. Transmission electron microscopy demonstrated spherical morphology of nanoemulsion droplets with diameter average of 40 nm. This study suggested that PSO nanoemulsion loading α-tocopherol could be introduced as delivery system with favorable features under severe environmental conditions.


Assuntos
Emulsões/química , Nanotecnologia , Óleos Vegetais/química , Romã (Fruta)/química , alfa-Tocoferol/química , Antioxidantes , Concentração Osmolar , Oxirredução , Sonicação
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