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1.
J Food Sci ; 89(2): 811-833, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38224177

RESUMO

This systematic review paper aims to discuss the trend in quality assessment properties and constituents of honey at different storage conditions and confer the possible whys and wherefores associated with the significant changes. Initially, a literature search was conducted through Google Scholar, ScienceDirect, PubMed, and Scopus databases. In total, 43 manuscripts published between 2001 and 2023 that met the inclusion and exclusion criteria were chosen for the review. As an outcome of this review, prolonged honey storage could deteriorate sensory, nutritional, and antioxidant properties and promote fermentation, granulation, microbial growth, carcinogenicity, organotoxicity, and nephrotoxicity. This systematic review also recognized that diastase activity, invertase activity, 5-hydroxymethylfurfural content, proline content, sugar content, amino acids, and vitamins could be used as indicators to distinguish fresh and stored honey based on the significant test (p-value) in the reported studies. However, all the reported studies used the simplest approach (one-way ANOVA) to identify the significant differences in the analyzed parameter during the storage period and none of them reported an approach to identify the most influential parameter at different storage conditions. In conclusion, orthogonal partial least squares discriminant analysis (supervised multivariate statistical tool) has to be employed in future studies to find the most influential parameter and could be used to potent chemical markers to distinguish fresh and stored honey because this analysis is incorporated with S-plot, variable importance of projection, and one-way ANOVA, which can produce the most accurate and precise results rather solely depending on one-way ANOVA.


Assuntos
Mel , Mel/análise , Antioxidantes/análise , Carboidratos/análise , Aminoácidos/análise , Prolina
2.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679372

RESUMO

Tea polyphenols, amino acids, soluble sugars, and other ingredients in fresh tea leaves are the key parameters of tea quality. In this research, a tea leaf ingredient estimation sensor was developed based on a multi-channel spectral sensor. The experiment showed that the device could effectively acquire 700-1000 nm spectral data of tea tree leaves and could display the ingredients of leaf samples in real time through the visual interactive interface. The spectral data of Fuding white tea tree leaves acquired by the detection device were used to build an ingredient content prediction model based on the ridge regression model and random forest algorithm. As a result, the prediction model based on the random forest algorithm with better prediction performance was loaded into the ingredient detection device. Verification experiment showed that the root mean square error (RMSE) and determination coefficient (R2) in the prediction were, respectively, as follows: moisture content (1.61 and 0.35), free amino acid content (0.16 and 0.79), tea polyphenol content (1.35 and 0.28), sugar content (0.14 and 0.33), nitrogen content (1.15 and 0.91), and chlorophyll content (0.02 and 0.97). As a result, the device can predict some parameters with high accuracy (nitrogen, chlorophyll, free amino acid) but some of them with lower accuracy (moisture, polyphenol, sugar) based on the R2 values. The tea leaf ingredient estimation sensor could realize rapid non-destructive detection of key ingredients affecting tea quality, which is conducive to real-time monitoring of the current quality of tea leaves, evaluating the status during tea tree growth, and improving the quality of tea production. The application of this research will be helpful for the automatic management of tea plantations.


Assuntos
Clorofila , Chá , Chá/química , Clorofila/análise , Aminoácidos/análise , Folhas de Planta/química , Polifenóis/análise , Polifenóis/metabolismo , Nitrogênio/análise , Açúcares/análise
3.
J Appl Toxicol ; 43(3): 446-457, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36101970

RESUMO

The amino acid derivative reactivity assay (ADRA), an alternative method for testing skin sensitization, has been established based on the molar concentration approach. However, the additional development of gravimetric concentration and fluorescence detection methods has expanded its range of application to mixtures, which cannot be evaluated using the conventional testing method, the direct peptide reactivity assay (DPRA). Although polymers are generally treated as mixtures, there have been no reports of actual polymer evaluations using alternative methods owing to their insolubility. Therefore, in this study, we evaluated skin sensitization potential of polymers, which is difficult to predict, using ADRA. As polymers have molecular weights ranging from several thousand to more than several tens of thousand Daltons, they are unlikely to cause skin sensitization due to their extremely low penetration into the skin, according to the 500-Da rule. However, if highly reactive functional groups remain at the ends or side chains of polymers, relatively low-molecular-weight polymer components may penetrate the skin to cause sensitization. Polymers can be roughly classified into three major types based on the features of their constituent monomers; we investigated the sensitization capacity of each type of polymer. Polymers with alert sensitization structures at their ends were classified as skin sensitizers, whereas those with no residual reactive groups were classified as nonsensitizers. Although polymers with a glycidyl group need to be evaluated carefully, we concluded that ADRA (0.5 mg/ml) is generally sufficient for polymer hazard assessment.


Assuntos
Compostos Orgânicos , Pele , Animais , Pele/metabolismo , Peptídeos/química , Bioensaio/métodos , Aminoácidos/análise , Alternativas aos Testes com Animais/métodos
4.
Anal Chem ; 94(28): 10127-10134, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35802862

RESUMO

To achieve the measurement reliability of amino acids used as diagnostic markers in clinical fields, establishing a reference measurement system is required, in which certified reference materials (CRMs) are an essential step in the hierarchy of measurement traceability. This study describes the development of dried blood spot (DBS) CRMs for amino acid analysis with complete measurement traceability to the International System of Units (SI). Six essential amino acids─proline, valine, isoleucine, leucine, phenylalanine, and tyrosine─were analyzed using isotope-dilution liquid chromatography-mass spectrometry (ID-MS). For minimizing measurement bias and uncertainty overestimation, whole spots with 50 µL of whole blood were adopted in the certification. The between-spot homogeneities by whole spot sampling were lower than 2.1%. The relative expanded uncertainties of the six amino acids in the developed DBS CRMs were lower than 5.7% at 95% confidence. The certified values are traceable to SI through both gravimetric preparation and the primary method in certification, ID-MS. Comparison among DBS testing laboratories revealed discrepancies between the whole spot and disc sampling methods. The actual sampling volume was accurately estimated by weighing, which revealed the possibility of underestimation in routine DBS testing. The candidate CRMs can support the standardization of DBS testing for amino acids through the qualification and validation of many kinds of measurement procedures to compensate the measurement bias caused by matrix-specific sampling error.


Assuntos
Aminoácidos , Teste em Amostras de Sangue Seco , Aminoácidos/análise , Certificação , Cromatografia Líquida/métodos , Padrões de Referência , Reprodutibilidade dos Testes
5.
Food Chem ; 385: 132674, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290950

RESUMO

The accurate measurement of bovine lactoferrin (bLF) attracts wide attention in food and nutraceutical applications as its important physiological and nutritional functions. We present SI traceable procedures for assessing bLF purity using mass balance method and amino acid (AA)-based isotope dilution mass spectrometry (IDMS). The mass balance method was revealed with a purity of 0.938 ± 0.011 g/g by deducting all aspects of impurities, including related structure impurities of 4.60%, ignition residue of 0.28%, Cl- of 1.10%, SO42- of 0.13%, and moisture of 0.17%. The AA-based IDMS quantitative result was 0.937 ± 0.027 g/g. Hydrolysis conditions were optimized and methodology validation including, accuracy, precision, were studied. Good consistency was achieved between the two independent strategies and bLF purity assigned via the weighted mean value of their results was 0.938 ± 0.015 g/g. These analyses are expected to be applicable to proteins quantification and development of LF certified reference materials.


Assuntos
Aminoácidos , Lactoferrina , Aminoácidos/análise , Cromatografia Líquida/métodos , Isótopos , Padrões de Referência , Espectrometria de Massas em Tandem/métodos
6.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1587-1594, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35347957

RESUMO

In this study, we analyzed the composition and content of 25 free amino acids in 32 batches of different forms of Cervi Cornu Pantotrichum(CCP; one-branched, two-branched, and three-branched) from 15 producing areas. The clustering analysis and orthogonal partial least squares discriminant analysis(OPLS-DA) were performed based on the content of 25 free amino acids. Potential differential metabolites were identified based on VIP value. The results showed that there were 25 free amino acids in CCP, and the average content of essential, non-essential, and total amino acids was 6.13, 32.99, and 39.12 mg·g~(-1), respectively. The clustering analysis and OPLS-DA demonstrated that 25 free amino acids had different content among the three forms of CCP, of which two-branched CCP samples were separately gathered into a group. Five differential components, including glutamic acid, tryptophan, ornithine, γ-aminobutyric acid, and hydroxylysine, were screened out as potential quality markers for the identification of different forms of CCP. This study provides a theoretical basis for the quality evaluation, processing, and utilization of different forms of CCP.


Assuntos
Cornus , Cervos , Gastrópodes , Aminoácidos/análise , Animais , Ácido Glutâmico
7.
Food Chem ; 383: 132436, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35183955

RESUMO

Keratin derived protein (KDP) was extracted from sheep wool using high pressure microwave technology and food acids and investigated for its potential as a novel dietary protein. The proximate composition, amino acid profile, element profile, in vitro cytotoxicity and digestibility of KDP were evaluated. Nutritive effects of KDP at 50% dietary supplementation were compared with a casein-based diet in a growing rat model for 95 days. Results indicate KDP to be rich in protein (86%), amino acid cysteine (8.8 g/100 g) and element selenium (0.29 µg/g). KDP was non-cytotoxic in vitro at ≤ 2 mg/mL concentration. There were no differences in the rat's weight gain compared to the control group (P > 0.05). Overall, the inclusion of the KDP in the diet was an effective substitute for casein protein at 50% and KDP has the potential to be used in the food industry as a novel dietary protein, free of fat and carbohydrate.


Assuntos
Queratinas , , Aminoácidos/análise , Ração Animal/análise , Animais , Caseínas/análise , Dieta/veterinária , Proteínas Alimentares/análise , Queratinas/química , Valor Nutritivo , Ratos , Ovinos , Lã/química
8.
Comput Math Methods Med ; 2021: 5770981, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413898

RESUMO

Antioxidant proteins (AOPs) play important roles in the management and prevention of several human diseases due to their ability to neutralize excess free radicals. However, the identification of AOPs by using wet-lab experimental techniques is often time-consuming and expensive. In this study, we proposed an accurate computational model, called AOP-HMM, to predict AOPs by extracting discriminatory evolutionary features from hidden Markov model (HMM) profiles. First, auto cross-covariance (ACC) variables were applied to transform the HMM profiles into fixed-length feature vectors. Then, we performed the analysis of variance (ANOVA) method to reduce the dimensionality of the raw feature space. Finally, a support vector machine (SVM) classifier was adopted to conduct the prediction of AOPs. To comprehensively evaluate the performance of the proposed AOP-HMM model, the 10-fold cross-validation (CV), the jackknife CV, and the independent test were carried out on two widely used benchmark datasets. The experimental results demonstrated that AOP-HMM outperformed most of the existing methods and could be used to quickly annotate AOPs and guide the experimental process.


Assuntos
Antioxidantes/química , Aprendizado de Máquina , Peroxirredoxinas/química , Proteínas/química , Algoritmos , Aminoácidos/análise , Antioxidantes/classificação , Biologia Computacional , Bases de Dados de Proteínas/estatística & dados numéricos , Evolução Molecular , Humanos , Cadeias de Markov , Peroxirredoxinas/classificação , Proteínas/classificação
9.
Nutrients ; 13(7)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201703

RESUMO

Global protein consumption has been increasing for decades due to changes in demographics and consumer shifts towards higher protein intake to gain health benefits in performance nutrition and appetite regulation. Plant-derived proteins may provide a more environmentally sustainable alternative to animal-derived proteins. This study, therefore, aimed to investigate, for the first time, the acute effects on glycaemic indices, gut hormones, and subjective appetite ratings of two high-quality, plant-derived protein isolates (potato and rice), in comparison to a whey protein isolate in a single-blind, triple-crossover design study with nine male participants (30.8 ± 9.3 yrs). Following a 12 h overnight fast, participants consumed an equal volume of the three isocaloric protein shakes on different days, with at least a one-week washout period. Glycaemic indices and gut hormones were measured at baseline, then at 30, 60, 120, 180 min at each visit. Subjective palatability and appetite ratings were measured using visual analogue scales (VAS) over the 3 h, at each visit. This data showed significant differences in insulin secretion with an increase in whey (+141.8 ± 35.1 pmol/L; p = 0.011) and rice (-64.4 ± 20.9 pmol/L; p = 0.046) at 30 min compared to potato protein. A significantly larger total incremental area under the curve (iAUC) was observed with whey versus potato and rice with p < 0.001 and p = 0.010, respectively. There was no significant difference observed in average appetite perception between the different proteins. In conclusion, this study suggests that both plant-derived proteins had a lower insulinaemic response and improved glucose maintenance compared to whey protein.


Assuntos
Biomarcadores/metabolismo , Glicemia/metabolismo , Ingestão de Alimentos , Oryza/química , Proteínas de Plantas/farmacologia , Solanum tuberosum/química , Proteínas do Soro do Leite/farmacologia , Adulto , Aminoácidos/análise , Apetite , Hormônios/sangue , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Peptídeos/sangue , Saciação , Escala Visual Analógica , Adulto Jovem
10.
Sci Rep ; 11(1): 15235, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315916

RESUMO

Fish silage is a brown liquefied product achieved by the action of enzymes when finely grounded whole/parts of either single or mixed fish types are subjected to acidification. This study made a comparative assessment of biochemical and nutritive properties, especially the amino acid composition in supernatant phase of formic acid silages prepared from two fish types, Indian mackerel (Rastrelliger kanagurta) and false travely (Lactarius lactarius) representing fat fish (FF, fat content > 5%) and lean fish (LF, fat content < 5%), respectively during 35 days of fermentation (DoF). Significantly higher content of total amino acid (TAA) and free amino acids (FAA) were recorded in FFS (TAA, 41.2 ± 0.03 mg/g; FAA, 31.3 ± 0.003 mg/g) compared to LFS (TAA, 35.8 ± 0.07 mg/g; FAA, 18.26 ± 0.003 mg/g; FAA, 31.3 ± 0.003 mg/g) (p < 0.05). At the end of 35 DoF, the concentrations of amino acids such as asparagine, histidine, isoleucine, valine, cysteine, serine, lysine and arginine were significantly higher in FFS as compared to LFS. The relative amino acid composition of FFS and LFS varied in accordance with DoF and the relationship was found to be highly significant (ANOVA, p < 0.00001). High concentrations of L-amino acids such as leucine, glutamic acid and arginine were recorded in both FFS and LFS. In conclusion, the analysis suggested that a fermentation period of 25-30 days showed a significant effect on the composition of amino acids in both types of ensilage compared to other fermentation periods (p < 0.05). Considering the role of amino acids in enhancing the plant growth and proliferation, the findings of the present study are quite useful.


Assuntos
Aminoácidos/análise , Produtos Pesqueiros/análise , Biologia Marinha , Silagem/análise , Aminoácidos/farmacologia , Animais , Fermentação , Reguladores de Crescimento de Plantas/farmacologia
11.
Biomed Chromatogr ; 35(1): e4990, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32959901

RESUMO

Of the various methods available for high-performance liquid chromatography separation of enantiomers (of e.g. amino acids and amino group containing compounds) by the pre-column derivatization approach, use of Marfey's reagent has been most successful with continued application since its introduction in 1984. The reagent is prepared from difluoro dinitro benzene by nucleophilic substitution of one of its F atoms by l-alanine amide. There is flexibility to prepare several chiral variants (by substituting the F atom with different chiral auxiliaries) and to tailor the hydrophobicity and resolution, ultimately, of the diastereomeric derivatives. The present paper assesses and reviews applications of Marfey's reagent and its chiral variants (i.e. other FDNP reagents) for enantioseparation of certain amino group containing drugs/amino acids, and to provide some case studies on enantiomeric separations that are important for the pharmaceutical industry. Various explanations for separation mechanism and elution order using FDNP reagents are included and the question of the configuration of the corresponding enantiomer using an indirect approach has also been addressed.


Assuntos
Alanina/análogos & derivados , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Dinitrobenzenos , Aminoácidos/análise , Aminoácidos/química , Aminoácidos/isolamento & purificação , Animais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Estereoisomerismo
12.
Amino Acids ; 53(1): 33-47, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33236255

RESUMO

Five isonitrogenous and isocaloric diets [containing 54, 30, 15, 10, and 5% fishmeal crude-protein (CP), dry matter (DM) basis] were prepared by replacing fishmeal with poultry by-product meal plus soybean meal to feed juvenile largemouth bass (LMB, with an initial mean body weight of 4.9 g) for 8 weeks. All diets contained 54% CP and 13% lipids. There were four tanks of fish per treatment group (15 fish/tank). The fish were fed twice daily with the same feed intake (g/fish) in all the dietary groups. Results indicated that the inclusion of 15% fishmeal protein in the diet is sufficient for LMB growth. However, some of the fish that were fed diets containing ≤ 15% fishmeal CP had black skin syndrome (characterized by skin darkening and retinal degeneration, as well as intestinal and liver atrophies and structural abnormalities). The concentrations of taurine, methionine, threonine and histidine in serum were reduced (P < 0.05) in fish fed the diets containing 5, 10 and 15% fishmeal CP, compared with the 30 and 54% fishmeal CP diets. Interestingly, the concentrations of tyrosine and tryptophan in serum were higher in fish fed diets with ≤ 15% fishmeal CP than those in the 54% fishmeal CP group. These results indicated that 15% fishmeal CP in the diet containing poultry by-product meal and soybean meal was sufficient for the maximum growth and feed efficiency in LMB but inadequate for their intestinal, skin, eye, and liver health. A reduction in dietary methionine and taurine content and the possible presence of antinutritional factors in the fishmeal replacements diets containing high inclusion levels of soybean meal may contribute to black skin syndrome in LMB. We recommend that the diets of juvenile LMB contain 30% fishmeal CP (DM basis).


Assuntos
Bass/fisiologia , Dieta/veterinária , Proteínas Alimentares/análise , Glycine max , Aves Domésticas , Aminoácidos/análise , Ração Animal/efeitos adversos , Ração Animal/análise , Ração Animal/economia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bass/crescimento & desenvolvimento , Bass/metabolismo , Composição Corporal , Custos e Análise de Custo , Ingestão de Alimentos , Doenças dos Peixes/etiologia , Doenças dos Peixes/patologia , Lipídeos/análise , Glycine max/química
13.
In Vitro Cell Dev Biol Anim ; 56(9): 773-782, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33025340

RESUMO

Sickle cell disease is a group of diseases inherited through the gene and it affects the haemoglobin in the red blood cell. This study investigated the methanol seed extract of Buchholzia coriacea for possible in vitro anti-sickling effects and also determined the effect of Mucuna pruriens seed extract on the solubility and oxygen-binding rate of sickle cell haemoglobin. Sickle cell blood was collected from sickle cell disease patients with subsequent addition of 2% sodium metabisulphite to cause more sickling. Varying concentrations of the seed extracts (50%, 25%, 12.5% and 6.25%) were added to the pre-treated blood for these in vitro assays. The results showed that the extract of Buchholzia coriacea significantly (P < 0.05) inhibited sickling at all concentrations with the highest percentage inhibition of 73.3 ± 5.8, reversed sickled erythrocytes at all concentrations with the highest percentage reversal of 83.3 ± 5.8 and significantly (P < 0.05) inhibited polymerisation at all concentrations used in comparison to the parallel control. The extract of Mucuna pruriens seed significantly (P < 0.05) increased the solubility of sickle haemoglobin at 50%, 25%, 12.5% and 6.25% concentrations, increased Fe2+/Fe3+ ratio from 1.7 (control) to 12.2 (50% concentration) and reduced osmotic fragility (at 12.5% and 6.25% concentrations) when compared with parallel control. The results indicate the feasibility of the seed extracts as promising agents in the management of sickle cell disease.


Assuntos
Antidrepanocíticos/farmacologia , Capparaceae/química , Mucuna/química , Extratos Vegetais/farmacologia , Sementes/química , Aminoácidos/análise , Anemia Falciforme/sangue , Hemoglobina Falciforme/metabolismo , Humanos , Ferro/sangue , Minerais/análise , Osmose/efeitos dos fármacos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Fitoterapia , Polimerização , Solubilidade
14.
PLoS One ; 15(9): e0239156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970742

RESUMO

A study evaluating apparent digestibilities of protein and amino acids and their corresponding digestion rates in four small intestinal sites in broiler chickens was completed to further investigate dietary optimisation via synchronised nutrient digestion and absorption. A total of 288 male Ross 308 broiler chickens were offered semi-purified diets with eight protein-rich feedstuffs, including; blood meal (BM), plasma protein meal (PPM), cold pressed (CCM) and expeller-pressed (ECM) canola meal, high (SBM HCP) and low (SBM LCP) crude protein soybean meals, lupins and peas. Diets were iso-caloric, iso-nitrogenous and the test ingredient was the sole source of dietary nitrogen. Each diet was offered to 6 bioassay cages with 6 birds per cage from day 21 to 28 post hatch. On day 28, all birds were euthanized and digesta samples were collected from the proximal jejunum, distal jejunum, proximal ileum and distal ileum to determine apparent protein and amino acids digestibility coefficients, digestion rates and potential digestible protein and amino acids. Dietary protein source significantly influenced energy utilisation, nitrogen retention, apparent protein (N) digestibilities, digestion rates and potential digestible protein along the small intestine. Diets containing BM and SBM LCP exhibited the highest protein digestion rate and potential digestible protein, respectively. Digestibility coefficients and disappearance rates of the majority of amino acids in four sections of the small intestine were influenced by dietary protein source (P < 0.01) and blood meal had the fastest protein digestion rate. In general, jejunal amino acid and protein digestibilities were more variable in comparison to ileal digestibilities, and the differences in protein and amino acid disappearance rates were more pronounced between types of feedstuffs than sources of similar feedstuffs.


Assuntos
Aminoácidos/metabolismo , Ração Animal , Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Proteínas Alimentares/metabolismo , Aminoácidos/administração & dosagem , Aminoácidos/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/análise , Íleo/metabolismo , Jejuno/metabolismo , Masculino
15.
Plant Cell Rep ; 39(12): 1655-1668, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32892290

RESUMO

KEY MESSAGE: Sustainability and safety aspects of plant cell cultures as food are presented. Applicability of dairy side streams as carbon source and use of natural growth enhancers in cultivation are shown. Biotechnologically produced cellular products are currently emerging to replace and add into the portfolio of agriculturally derived commodities. Plant cell cultures used for food could supplement current food production. However, still many aspects need to be resolved before this new food concept can enter the market. Issues related to sustainability and safety for human consumption are relevant for both consumers and regulators. In this study, two plant cell cultures, deriving from arctic bramble (Rubus arcticus) and birch (Betula pendula), were cultivated using lactose-rich dairy side streams as alternative carbon sources to replace sucrose. Biomasses were comparable to those of original plant cell culture media when up to 83% and 75% of the original sucrose was replaced by these side streams for arctic bramble and birch cell cultures, respectively. Furthermore, nutritional composition or sensory properties were not compromised. Synthetic plant growth regulators were replaced by natural components, such as coconut water and IAA for several subculture cycles. Finally, it was shown that only trace amounts of free growth regulators are present in the cells at the harvesting point and assessment by freshwater crustaceans assay indicated that toxicity of the cells was not exceeding that of traditionally consumed bilberry fruit.


Assuntos
Betula/citologia , Técnicas de Cultura de Células/métodos , Células Vegetais , Rubus/citologia , Aminoácidos/análise , Animais , Carboidratos/análise , Carboidratos/química , Meios de Cultura/química , Daphnia/efeitos dos fármacos , Inocuidade dos Alimentos , Humanos , Odorantes , Células Vegetais/química , Reguladores de Crescimento de Plantas/análise , Reguladores de Crescimento de Plantas/metabolismo , Sacarose/metabolismo , Desenvolvimento Sustentável , Testes de Toxicidade/métodos
16.
Int J Med Mushrooms ; 22(6): 559-571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865897

RESUMO

Trametes versicolor is important for its medicinal rather than nutritional value. It has a variety of pharmacological activities. The purpose of this study was to elucidate the bioactive properties of the wild medicinal mushroom T. versicolor (L.) Lloyd. Samples were analyzed for antioxidant potential and the chemical composition of the major bioactive chemical components. Chromatographic procedures were used to analyze phenolic compounds, free amino acids, vitamins, and fatty acids. T. versicolor was analyzed for moisture (87.21 ± 1.08 g/100 g fw), protein (11.07 ± 0.85 g/100 g dw), and fat (1.35 ± 0.09 g/100 g dw) content. Phenolic compounds in T. versicolor were found as p-hydroxy benzoic (113.16 ± 0.22 µg/g dw), protocatechuic (10.07 ± 0.54 µg/g dw), vanillic (5.21 ± 0.10 µg/g dw), and homogentisic acids (1.24 ± 0.15 µg/g dw). In the studied mushroom, essential and nonessential amino acids were determined as leucine (72.41 ± 0.16 mg/100 g dw), isoleucine (60.07 ± 0.10 mg/100 g dw), methionine (53.51 ± 0.09 mg/100 g dw), tyrosine (33.37 ± 0.27 mg/100 g dw), glutamine (15.48 ± 0.19 mg/100 g dw), and asparagine (10.90 ± 0.13 mg/100 g dw). Vitamin content of T. versicolor was found as nicotinic acid (26.52 ± 0.10 mg/100 g dw) and nicotinamide (12.18 ± 0.05 mg/100 g dw). Fatty acids in T. versicolor were linoleic acid (18:2n6c), oleic acid (18:1n9c), palmitic acid (C16:0), stearic acid (C18:0), and linolenic acid (18:3n3). In conclusion, the results of the present study support the potential use of T. versicolor as a promising source of bioactive products for pharmaceutical and also food industries.


Assuntos
Antioxidantes/análise , Polyporaceae/química , Aminoácidos/análise , Ácidos Graxos/análise , Flavonoides/análise , Valor Nutritivo , Fenóis/análise , Vitaminas/análise
17.
Anal Chem ; 92(19): 13500-13508, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32842726

RESUMO

Inductively coupled plasma-mass spectrometry (ICP-MS) has been widely used in Life Sciences for the absolute quantification of biomolecules without specific standards, assuming the same response for generic compounds including complex biomolecules. However, contradictory results have been published on this regard. We present the first critical statistical comparison of the ICP-MS response factors obtained for 14 different relevant S-containing biomolecules (three peptides, four proteins, one amino acid, two cofactors, three polyethylene glycol (PEG) derivatives, and sulfate standard), covering a wide range of hydrophobicities and molecular sizes. Two regular flow nebulizers and a total consumption nebulizer (TCN) were tested. ICP-MS response factors were determined though calibration curves, and isotope dilution analysis was used to normalize the results. No statistical differences have been found for low-molecular-weight biocompounds, PEGs, and nonhydrophobic peptides using any of the nebulizers tested. Interestingly, while statistical differences were still found negligible (96-104%) for the proteins and hydrophobic peptide using the TCN, significantly lower response factors (87-40%) were obtained using regular flow nebulizers. Such differential behavior seems to be related mostly to hydrophobicity and partially to the molecular weight. Findings were validated using IDA in intact and digested bovine serum albumin solutions using the TCN (98 and 100%, respectively) and the concentric nebulizer (73 and 97%, respectively). Additionally, in the case of a phosphoprotein, results were corroborated using the P trace in parallel to the S trace used along the manuscript. This work seems to suggest that ICP-MS operated with regular nebulizers can offer absolute quantification using generic standards for most biomolecules except proteins and hydrophobic peptides.


Assuntos
Aminoácidos/análise , Disciplinas das Ciências Biológicas , Peptídeos/análise , Polietilenoglicóis/análise , Proteínas/análise , Sulfatos/análise , Espectrometria de Massas
18.
Comput Math Methods Med ; 2020: 1384749, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32300371

RESUMO

Prediction of DNA-binding proteins (DBPs) has become a popular research topic in protein science due to its crucial role in all aspects of biological activities. Even though considerable efforts have been devoted to developing powerful computational methods to solve this problem, it is still a challenging task in the field of bioinformatics. A hidden Markov model (HMM) profile has been proved to provide important clues for improving the prediction performance of DBPs. In this paper, we propose a method, called HMMPred, which extracts the features of amino acid composition and auto- and cross-covariance transformation from the HMM profiles, to help train a machine learning model for identification of DBPs. Then, a feature selection technique is performed based on the extreme gradient boosting (XGBoost) algorithm. Finally, the selected optimal features are fed into a support vector machine (SVM) classifier to predict DBPs. The experimental results tested on two benchmark datasets show that the proposed method is superior to most of the existing methods and could serve as an alternative tool to identify DBPs.


Assuntos
Algoritmos , Proteínas de Ligação a DNA/química , Aprendizado de Máquina , Sequência de Aminoácidos , Aminoácidos/análise , Biologia Computacional , Proteínas de Ligação a DNA/genética , Bases de Dados de Proteínas/estatística & dados numéricos , Humanos , Cadeias de Markov , Curva ROC , Máquina de Vetores de Suporte
19.
Int J Med Mushrooms ; 22(11): 1079-1088, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33426839

RESUMO

Information on the biosafety of tiger sawgill mushroom, Lentinus tigrinus, is limited and controversial. In the present study, the toxicity of a native L. tigrinus strain was evaluated in both cell cultures and mice. In addition to proximate analysis, the amino acid composition and the substrate-dependent uptake of elements were also evaluated. The mushroom (dry weight) had 7.53 ± 0.11% ash, 4.23 ± 0.23% lipid, 13.4 ± 0.04% fiber, 74.84 ± 0.38% total carbohydrate, and 4.16 ± 0.08 (mg GAEs/g) total phenol. Lysine was found at the highest amount among the L-amino acids determined in the L. tigrinus soluble protein. Comparison of the elemental profile of L. tigrinus with that of the substrate demonstrated a great capacity for absorption of K, P, S, and Mg elements, while the Na uptake was low. Neither the substrate nor the mushroom contained toxic elements beyond the standards of the joint FAO/WHO. The viability of normal human and mouse-derived cells was not influenced by the extract up to 250 µg/mL, where 70% of cancerous PC3 and MCF-7 cells were killed. Selectivity index analysis suggested that the L. tigrinus extract was selective only against MCF-7 cells. The extract also did not affect mice treated orally or via i.p. injection, while i.v. injection caused some mortality in mice with an LD50 of 47.19 mg/mL. In conclusion, L. tigrinus may be considered a source of macronutrients and micronutrients with a selective anticancer activity, while it is much less likely to have detrimental effects on humans at low serving levels.


Assuntos
Lentinula/química , Extratos Vegetais/química , Aminoácidos/análise , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibras na Dieta/análise , Humanos , Irã (Geográfico) , Camundongos , Avaliação Nutricional , Fenol/análise , Extratos Vegetais/toxicidade
20.
Food Res Int ; 126: 108729, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31732033

RESUMO

Serra da Estrela cheese is a high-value Portuguese Protected Designation of Origin cheese, produced with raw ewe milk. Thus, information regarding its composition is of utmost relevance for both consumers and certified producers. In this work, the chromatographic profiles of free amino acids in cheeses (45 days of maturation, 6 producers located in 5 municipalities and produced from November 2017 to March 2018) were established by UPLC-DAD-MS/MS. The proposed method allowed detecting 19 free amino acids and cystine with overall limits of detection and quantification lower than 44 µmol/L (1.4 mg/100 g cheese, wet matter) and than 134 µmol/L (4.2 mg/100 g cheese, wet matter), respectively. In all cheeses, 17 free amino acids were quantified including 8 essential amino acids (histidine, leucine-isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine) and 9 non-essential amino acids (arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, proline, serine and tyrosine). The amounts of the free amino acids, essential free amino acids, branched chain free amino acids (leucine, isoleucine and valine) plus the free amino acids ratios (mg/g protein) were further used to identify the producer of Serra da Estrela cheeses. Linear discriminant analysis coupled with the simulated annealing variable selection algorithm was used allowing the correct classification of 96% and 90 ±â€¯8% of the samples, for leave-one-out and repeated K-fold cross-validation procedures, respectively. The satisfactory predictive performance pointed out the possibility of using cheeses' amino acids profiles as origin biomarkers for authenticity control, warranting the correctness identification of the cheese producer/brand, which is quite relevant for ensuring the consumer confidence and satisfaction when purchasing this high-value dairy food.


Assuntos
Aminoácidos/análise , Queijo/análise , Queijo/classificação , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Portugal
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