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1.
Food Chem ; 366: 130532, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274702

RESUMO

One major pepsinogen, PG-I, and two minor pepsinogens, PG-II and PG-III were purified from lizardfish stomach by ammonium sulfate precipitation and two chromatographic columns. The three purified PGs migrated as single bands in native-PAGE gels with molecular weights (MW) ranging from 36 to 38 kDa. Each PG was converted to pepsin (P) at pH 2.0, and the MW were determined as 32 kDa (for P-I), 31 kDa (for P-II) and 30 kDa (for P-III). The optimum pH and temperature of pepsins were 2.0-3.5, and 40-50 °C. All 3 pepsins were strongly inhibited by pepstatin A. Divalent cations slightly stimulated the pepsin activities, but ATP had no effect on the pepsins. Purified pepsins were effective in the hydrolysis of various proteins. Km and kcat of the three pepsins for hemoglobin hydrolysis were 107.64-276.61 µM and 18.30-32.68 s-1, respectively. The new pepsins have potential for use in protein food procession and modification.


Assuntos
Pepsina A , Pepsinogênios , Sequência de Aminoácidos , Animais , Peixes/metabolismo , Pepsina A/metabolismo , Pepsinogênios/metabolismo , Estômago
2.
Food Chem ; 366: 130490, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274703

RESUMO

In this study, a novel signal amplification strategy on photoelectrochemical (PEC) aptasensor was designed for high-sensitivity and -selectivity detection of 3,3',4,4'-tetrachlorobiphenyl (PCB77) on the basis of Schottky junction and sensitization. First, the Schottky barrier not only provided an electron-transfer irreversible passage from CuO to Au Nanoparticles (NPs) but also generated excellent local surface plasmon resonance between CuO and Au NPs, thus improving the efficiency of charge separation and light absorption. Second, to further improve the response of the PEC aptasensor under the action of the sensitization, the complementary-DNA-functionalized CdS quantum dots were introduced onto the surface of CuO/Au NPs via hybridization of the target aptamer. The PEC aptasensor exhibited a low detection limit of 17.3 pg L-1, and a wide linear response was shown at a range of 0.2-220 ng L-1 depending on the variation of photocurrent before and after incubation.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Animais , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Bifenilos Policlorados
3.
Food Chem ; 366: 130533, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274704

RESUMO

We performed a multiscale study to understand the impact of pure exogenous compounds at low concentration on the crystallization of triacylglycerols (TAGs) in anhydrous milk fat (AMF). We selected butyric acid, an inhibitor of crystallization, and palmitic acid, a promotor, to investigate the influence of the chain length. Tripalmitin was also used as a promotor to assess the impact of fatty acid esterification. Melted blends containing the additives (1 wt%) were quenched at 25 °C. X-ray scattering data showed that AMF TAGs crystallized directly in the ß'-2L form. The presence of additives did not modify the nanostructure of TAG crystals. However, they significantly altered the microstructure of AMF, as revealed by polarized light microscopy and rheology. This study emphasizes the interest of a multiscale approach to gain knowledge about the behavior of complex fat blends and of the use of modulators at low concentration to monitor their textural properties.


Assuntos
Ácidos Graxos não Esterificados , Nanoestruturas , Animais , Cristalização , Ésteres , Leite
4.
Food Chem ; 366: 130531, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284182

RESUMO

Phytochemical electrophiles are drawing significant attention due to their properties to modulate signaling pathways related to cellular homeostasis. The aim of this study was to develop new tools to examine the electrophilic activity in food and predict their beneficial effects on health. We developed a spectrophotometric assay based on the nitrobenzenethiol (NBT) reactivity, as a thiol-reactive nucleophile, to screen electrophiles in tomato fruits. The method is robust, simple, inexpensive, and could be applied to other types of food. We quantified the electrophile activity in a tomato collection and associated this activity with the pigment composition. Thus, we identified lycopene, ß- and γ-carotenes, 16 by-products of carotenoid oxidation and 18 unknown compounds as NBT-reactive by HPLC-MS/MS. The potential benefits of NBT-reactive compounds on health were evaluated in the in vivo model of C. elegans where they activated the SKN-1/Nrf2 pathway, evidencing the ability of electrophilic compounds to induce a biological response.


Assuntos
Proteínas de Caenorhabditis elegans , Lycopersicon esculentum , Animais , Caenorhabditis elegans/genética , Proteínas de Ligação a DNA , Suplementos Nutricionais , Fator 2 Relacionado a NF-E2/genética , Espectrometria de Massas em Tandem , Fatores de Transcrição
5.
Food Chem ; 366: 130579, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284187

RESUMO

This work evaluated the effect of micro- and nano-starch (MS and NS) on the gel properties of fish myofibrillar protein (MP). Both MS and NS could enhance MP gel performance in terms of breaking force, elasticity and water holding capacity (p < 0.05), with more significant effect from NS than MS. The difference between NS and MS in enhancement effect on MP gel is due to nano-size effect and different microstructures of MP/MS and MP/NS gels, with NS rather than MS contributing to the continuity of MP network. Synchrotron FTIR micro-spectroscopic images further verified that NS with large specific surface had good compatibility with MP, while MS was embedded in MP matrix with evident phase separation. Additionally, ß-sheet still dominated the secondary structure of all gels, although adding both MS and NS could change molecular interactions, such as weakening ionic bonds and hydrogen bonds, and strengthening hydrophobic interactions.


Assuntos
Carpas , Amido , Animais , Géis , Interações Hidrofóbicas e Hidrofílicas , Proteínas Musculares , Reologia , Água
6.
Food Chem ; 366: 130554, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34284188

RESUMO

Standard fermentation (SF) mainly affected the metabolism of glycerophospholipid and sphingolipid, and increased the total lipid content of goat milk. Content of total lipid was decreased by magnetic fermentation compared with SF, mainly due to triacylglycerol and diacylglycerol. Comprehensive characteristic of lipids dynamic changes during standard and magnetic fermentation was performed using high-throughput quantitative lipidomics. Totally, 488 lipid molecular species covering 12 subclasses were detected, and triacylglycerol was the highest levels, followed by diacylglycerol and phosphoethanolamine in the whole fermentation stage. Specifically, except for ceramide and simple Glc series, the content of all polar lipids in SF was dropped and neutral lipids subjoined. Compared with SF, the decrease of triacylglycerol (1752.47 to 784.78 µg/mL), diacylglycerol (60.36 to 24.89 µg/mL) and simple Glc series (4.36 to 2.40 µg/mL) were observed, while ceramide (6.54 to 25.87 µg/mL) increased, suggesting magnetic fermentation as effective approach to potentially improve the nutritional of goat milk.


Assuntos
Lipídeos , Leite , Animais , Fermentação , Cabras , Lipídeos/análise , Fenômenos Magnéticos , Leite/química , Valor Nutritivo
7.
Food Chem ; 366: 130596, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34293545

RESUMO

Clarification of the mechanism of heat-induced gel formation by proteins under natural food systems could provide important references for the regulation of food texture. In the present study, the proteins involved in the early stage (heating at 72 °C for 8 min) of egg-white thermal gel (EWG) formation were studied quantitatively through comparative proteomic analysis. We discovered that the abundance of ovalbumin and ovomucoid increased significantly (p < 0.01), whereas that of ovotransferrin, lysozyme, ovomucin (mucin 5B and mucin 6) decreased significantly (p < 0.01), in the supernatant of EWG. If the initial interaction of egg white proteins was altered by ultrasonic pretreatment, the abundance of ovomucin and lysozyme in the supernatant of EWG increased, and was accompanied by the change from a solid gel to a fluid gel. Based on these results, we hypothesize that ovomucin has a key role in the formation and regulation of EWG properties.


Assuntos
Ovomucina , Proteômica , Animais , Galinhas , Conalbumina , Proteínas do Ovo , Ovalbumina
8.
Food Chem ; 366: 130590, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311230

RESUMO

A paper-based electrochemiluminescence device (µPAD-ECL) for the estimation of trimethylamine (TMA) concentration in fish was developed using tris(2,2'-bipyridyl)ruthenium(II) complex coupled with water soluble thioglycolic acid-capped CdSe quantum dots on the inkjet-printed paper-based device. The quenching effect of tertiary amines on the ECL intensity was found to be sensitive and concentration dependent. This effect allows the measurement of TMA at low concentrations. Under the optimal conditions, the linear concentration range was exhibited from 1 × 10-12 to 1 × 10-7 M and a detection limit of 2.09 × 10-13 M, with relative standard deviation of 1.97 %. The applicability of µPAD-ECL is demonstrated by the rapid estimation of trimethylamine concentration in fish tissue, and could be used as a method for screening the total amount of tertiary amines in fishery products in remote communities. The results obtained using the paper-based devices agreed well with those obtained applying high performance liquid chromatography with benzoyl derivatization, at a confidence level of 95%.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Animais , Medições Luminescentes , Metilaminas , Compostos de Selênio , Tioglicolatos
9.
Food Chem ; 366: 130573, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311232

RESUMO

Based on a murine monoclonal antibody (mAb) against tiamulin (TML), an electrochemical immunosensor was proposed using silver-graphene oxide (Ag-GO) nanocomposites and gold nanocomposites (AuNPs) to detect tiamulin (TML). Due to the synergetic properties of Ag-GO nanocomposites and AuNPs, the conductivity of the immunosensor was significantly enhanced. On account of the specific mAb and conductive nanocomposites, the proposed electrochemical immunosensor exhibited a low LOD of 0.003 ng mL-1 for the detection of TML in a wide linear range of 0.01 to 1000 ng mL-1. In addition, the immunosensor did not involve additional redox species. Furthermore, the efficient and simple electrochemical immunosensor was employed to detect TML in real samples with high accuracy, suggesting a potential detection platform for other veterinary antibiotics in animal derived foods.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Animais , Anticorpos Monoclonais , Diterpenos , Técnicas Eletroquímicas , Ouro , Imunoensaio , Limite de Detecção , Camundongos
10.
Food Chem ; 366: 130600, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311237

RESUMO

The effect of dual-frequency sequential ultrasonic thawing (DUT) on the quality of quick-frozen small yellow croaker was studied by TMT-labeled quantitative proteomic method. A total number of 75 proteins were identified as differentially abundant proteins (DAPs) in fish meat treated by DUT, while 72 DAPs were in flow water thawing (FWT). The Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis indicated that the DAPs in the significant enrichment pathway of DUT group were enzymes. Compared with FWT, DUT had a significant effect on the enzyme content. The correlation analyses indicated that 40 DAPs were related with the quality traits. The 11 highly correlated DAPs are expected to be used as potential protein markers for texture profile analyses, color, thawing loss, water-holding capacity, and pH of thawed small yellow croaker quality. These results provide a further understanding of the quality stability of quick-frozen small yellow croaker treated by the DUT.


Assuntos
Perciformes , Proteômica , Animais , Peixes , Genoma , Carne , Perciformes/genética
11.
Food Chem ; 366: 130636, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34314929

RESUMO

The study aimed to determine the efficiency of advanced chelate compounds-based trace minerals (OTM) in laying hens. Laying hens (240, 32 weeks old) were assigned to one of the following five groups: NOTM (no added trace minerals), CONTM (standard mineral salts), and three experimental groups in which chelates were used to replace 33, 66, and 100% of mineral salts (OTM33, OTM66, and OTM100, respectively). Each treatment had six replicates with eight hens per replicate. After 18 weeks, performance and physicochemical properties of eggs in all experimental groups was better than those in the NOTM group. Among the treatments, OTM66 and OTM100 produced the best results in terms of laying performance, yolk PUFA/SFA ratio, Zn and Se contents, and malondialdehyde concentration in both serum and yolk. In conclusion, up to 66% OTM supplementation was beneficial for performance, lipid and mineral composition of yolk, and oxidative status.


Assuntos
Galinhas , Ácidos Graxos , Ração Animal/análise , Animais , Dieta , Suplementos Nutricionais , Gema de Ovo/metabolismo , Ácidos Graxos/metabolismo , Feminino , Minerais/metabolismo , Estresse Oxidativo
12.
Food Chem ; 366: 130597, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34314935

RESUMO

We investigated the effect of bee species identity and harvesting methods on the chemical composition and antiradical activity of 53 honey samples, produced by six stingless bee species in western Kenya (Kakamega forest). Our results illustrate that none of the assayed parameters significantly varied between the honey samples harvested by "punching holes" (n = 25) and "squeezing" (n = 28) methods. By contrast, species identity drove significant differences in the assayed parameters. Positive correlations between the antiradical activity and the phytochemicals (phenols and flavonoids) were observed, and honeys from Liotrigona sp. exhibited the highest amounts of phenols (214 mg GAE/100 g), flavonoids (73.0 mg QE/100 g) and antiradical activity (76.2%). The physicochemical analyses confirm the need to establish separate stingless bee honey standards for moisture, free acidity, invertase, electrical conductivity, and HMF, as these parameters significantly diverged from the set limits for Apis mellifera honey.


Assuntos
Mel , Himenópteros , Animais , Abelhas , Flavonoides , Quênia , Simpatria
13.
Food Chem ; 366: 130648, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325245

RESUMO

A novel label-free fluorescence aptasensor was established for chloramphenicol (CAP) detection by DNA four-arm junction-assisted target recycling and SYBR Green I dye-aided fluorescence-signal amplification. The CAP aptamer was hybridized to its complementary strand (primer) to form a double-stranded primer/aptamer complex. In the presence of CAP, aptamers can specifically bind with CAP to dissociate primers, which can trigger the self-assembly of four hairpins to continuously generate DNA four-arm junctions. After digesting the excess hairpins using T7 exonuclease, SYBR Green I was inserted into the base pair-rich DNA four-arm junctions, which led to a significant increase in fluorescence intensity. Under optimal conditions, the developed aptasensor can detect CAP in a linear range of 1.0 pg mL-1 to 10 ng mL-1 with a detection limit of 0.72 pg mL-1. The recovery rates in milk and honey ranged from 90.3% to 106.6%. Thus, the method shows substantial potential for CAP detection in food products.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Animais , Cloranfenicol/análise , DNA , Limite de Detecção , Leite/química
14.
Food Chem ; 366: 130587, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34332424

RESUMO

Miniaturized and simplified sample preparation methods with reduced consumption of chemicals and non-halogenated solvents are presented for the determination of 12 sulfonamides in baby foods. Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was used for the identification and quantification of the compounds based on the acquisition of full spectrum at high resolution with accurate mass for precursor and its fragment ions. Three miniaturized protocols based on QuEChERS, salting-out assisted liquid-liquid extraction or low-temperature cleanup were evaluated regarding the extraction efficiency and removal capability of matrix co-extractives. All approaches achieved satisfactory recoveries (70.0-120.0%); however, the miniaturized QuEChERS distinguished by lower co-extractives content in the final extract providing lower matrix effects. Thus, the performance characteristics of the miniaturized QuEChERS were established using different matrices: beef-, egg yolk- and vegetable-based baby food or chicken- and vegetable-based baby food, in compliance with the Codex Alimentarius Commission guidelines. The target compounds were investigated in 30 commercial baby foods.


Assuntos
Antibacterianos , Alimentos Infantis , Animais , Bovinos , Cromatografia Líquida , Alimentos Infantis/análise , Espectrometria de Massas , Carne/análise , Sulfonamidas
15.
Food Chem ; 366: 130685, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333182

RESUMO

This review aimed to retrieve the most recent research with strong impact concerning the application of metabolomics analysis in food processing. The literature reveals the high capacity of this methodology to evaluate chemical and organoleptic transformations that occur during food production. Current and potential applications of metabolomics analysis will be addressed, focusing on process-composition-function relationships. The use of the metabolomics approach to evaluate transformations in foods submitted to minimal processes, heat or cold treatments, drying, fermentation, chemical and enzymatic treatments and processes using innovative technologies will be discussed. Moreover, the main strategies and advantages of metabolomics-based approaches are reviewed, as well as the most used analytical platforms. Overall, metabolomics can be seen as an important tool to support academia and industry on pursuing knowledge about the transformation of raw animal or plant materials into ready-to-eat products.


Assuntos
Manipulação de Alimentos , Metabolômica , Animais , Fermentação , Alimentos
16.
Food Chem ; 367: 130658, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343808

RESUMO

Camel milk is rich in nutrients and its impact on human medicine and nutrition cannot be ignored. We conducted an in-depth analysis of milk proteins obtained from two camel breed (Camelus bactrianus, CB and Camelus dromedarius, CD). Label-free proteomic technology was performed to analysis the MFGM and whey proteomes of CB and CD milk. In total, 1133 MFGM proteins and 627 whey proteins were identified from camel milk. Results revealed that 216 MFGM proteins and 109 whey proteins were significantly different between them. In addition, the cellular process, cell and binding were the predominately GO annotations of milk proteins. KEGG analysis shown that most proteins were involved in metabolic pathways. Furthermore, many proteins were found to be involved in PI3K/AKT signaling pathway, which could be the possible reason for hypoglycemic effect of camel milk. These results could provide a further understanding for unique biological characteristics of camel milk proteins.


Assuntos
Camelus , Proteoma , Animais , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Proteínas do Leite , Fosfatidilinositol 3-Quinases , Proteômica , Soro do Leite , Proteínas do Soro do Leite
17.
Food Chem ; 367: 130663, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343810

RESUMO

Effects of high internal phase emulsion (HIPE) stabilized by egg yolk-modified starch complex on the gelling properties of chicken gels with or without sodium chloride (NaCl)/sodium tripolyphosphate (TP) were studied. The addition of 30 % HIPE increased the hardness from 376 g to 590 g. The NaCl addition further improved textural and viscoelastic properties compared with the gels without NaCl. 30 % HIPE-filled gels with salts (NaCl and TP) has the highest hardness (3562 g) and the lowest cooking loss (3.41 %). Fourier transform infrared spectra (FTIR) revealed that salts, especially TP, could promote the transition of α-helices to ß-sheets structure. Moreover, the chicken gels with TP had higher acyl chain disorder. In summary, the co-addition of HIPE and salt (NaCl/TP) has a positive effect on the formation of chicken gel, thereby providing potential applications in comminuted meat products.


Assuntos
Galinhas , Produtos da Carne , Animais , Emulsões , Géis , Produtos da Carne/análise , Sais
18.
Food Chem ; 366: 130690, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343949

RESUMO

Enzymatic-assisted extraction using Flavourzyme® has been demonstrated to be a useful methodology to obtain wine lees (WL) enriched in phenolic compounds and with enhanced antihypertensive activity. Nevertheless, taking into account that Flavourzyme® possess proteolytic activity, the release of bioactive peptides should not be ruled out. In this study, we investigate the presence of antihypertensive peptides in the WL hydrolysate. Peptides were separated into fractions by ultrafiltration and RP-HPLC. Next, peptide identification by nano-HPLC-(Orbitrap)MS/MS was performed in the fractions showing the highest angiotensin-converting enzyme inhibitory (ACEi) activities. Six peptides were identified; three of them showing ACEi (IC50) values lower than 20 µM. The peptide antihypertensive effect was evaluated in spontaneously hypertensive rats at an oral dose of 10 mg/kg bw. Peptides FKTTDQQTRTTVA, NPKLVTIV, TVTNPARIA, LDSPSEGRAPG and LDSPSEGRAPGAD exhibited antihypertensive activity, confirming that they could contribute to the blood pressure-lowering effect of the WL hydrolysate. These peptides have a great potential as functional ingredients to manage hypertension.


Assuntos
Hipertensão , Vinho , Inibidores da Enzima Conversora de Angiotensina , Animais , Anti-Hipertensivos , Hipertensão/tratamento farmacológico , Peptídeos , Hidrolisados de Proteína , Ratos , Espectrometria de Massas em Tandem
19.
Food Chem ; 366: 130712, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343953

RESUMO

The aim of this study was to investigate the effect of selenium enrichment on the gel properties and gastrointestinal digestive properties of egg white. Results of texture profile analysis, scanning electron microscopy and differential scanning calorimetry showed that the heat-induced gel of selenium-enriched egg white (EW-2) exhibited higher gel strength, smoother microstructure, and higher thermal denaturation temperature than ordinary egg white (EW-1), which might be due to the change of ovomucin and ovotransferrin content. The gastrointestinal digestive products of the EW-2 protein contained a higher proportion of small peptides and more free amino acids than those of EW-1. Results of oxygen radical absorbance capacity and cellular antioxidant activity assays indicated that digestive products of the EW-2 protein exhibited stronger antioxidant activity than those of the EW-1 protein. In summary, Se enrichment improved heat-induced gel properties of egg white, and promoted the gastrointestinal digestion of egg white protein.


Assuntos
Selênio , Animais , Galinhas , Digestão , Feminino , Temperatura Alta , Saccharomyces cerevisiae
20.
Food Chem ; 367: 130680, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34348198

RESUMO

This study investigated the effect of different types of smoking materials on the flavor, heterocyclic aromatic amine (HAA) content, and sensory attributes of smoked chicken drumsticks. All smoked samples showed lower pH and L*-value and higher a*-value and b*-value than the control sample (P < 0.05), but no significant differences in water content and water activity (P > 0.05). The samples smoked with sucrose combined with pear-tree woodchips (SP) or green tea leaves (ST) had higher overall acceptability than other samples (P < 0.05). Smoking increased the total HAA content, and the ST sample exhibited the highest total HAA content (P < 0.05). A total of 54 volatile compounds was identified. Overall, SP and ST are suitable for smoked chicken considering the sensory properties, while S and SA are proper for smoked chicken considering the minimization of HAAs, which may provide a theory basis for the production of smoked chicken.


Assuntos
Galinhas , Compostos Heterocíclicos , Aminas/análise , Animais , Fumaça , Fumar
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