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1.
J Appl Oral Sci ; 28: e20190501, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236356

RESUMO

INTRODUCTION: The acquired pellicle formation is the first step in dental biofilm formation. It distinguishes dental biofilms from other biofilm types. OBJECTIVE: To explore the influence of salivary pellicle formation before biofilm formation on enamel demineralization. METHODOLOGY: Saliva collection was approved by Indiana University IRB. Three donors provided wax-stimulated saliva as the microcosm bacterial inoculum source. Acquired pellicle was formed on bovine enamel samples. Two groups (0.5% and 1% sucrose-supplemented growth media) with three subgroups (surface conditioning using filtered/pasteurized saliva; filtered saliva; and deionized water (DIW)) were included (n=9/subgroup). Biofilm was then allowed to grow for 48 h using Brain Heart Infusion media supplemented with 5 g/l yeast extract, 1 mM CaCl2.2H2O, 5% vitamin K and hemin (v/v), and sucrose. Enamel samples were analyzed for Vickers surface microhardness change (VHNchange), and transverse microradiography measuring lesion depth (L) and mineral loss (∆Z). Data were analyzed using two-way ANOVA. RESULTS: The two-way interaction of sucrose concentration × surface conditioning was not significant for VHNchange (p=0.872), ∆Z (p=0.662) or L (p=0.436). Surface conditioning affected VHNchange (p=0.0079), while sucrose concentration impacted ∆Z (p<0.0001) and L (p<0.0001). Surface conditioning with filtered/pasteurized saliva resulted in the lowest VHNchange values for both sucrose concentrations. The differences between filtered/pasteurized subgroups and the two other surface conditionings were significant (filtered saliva p=0.006; DIW p=0.0075). Growing the biofilm in 1% sucrose resulted in lesions with higher ∆Z and L values when compared with 0.5% sucrose. The differences in ∆Z and L between sucrose concentration subgroups was significant, regardless of surface conditioning (both p<0.0001). CONCLUSION: Within the study limitations, surface conditioning using human saliva does not influence biofilm-mediated enamel caries lesion formation as measured by transverse microradiography, while differences were observed using surface microhardness, indicating a complex interaction between pellicle proteins and biofilm-mediated demineralization of the enamel surface.


Assuntos
Biofilmes/crescimento & desenvolvimento , Esmalte Dentário/microbiologia , Saliva/química , Sacarose/química , Desmineralização do Dente/microbiologia , Animais , Bovinos , Esmalte Dentário/química , Película Dentária/microbiologia , Dureza , Microrradiografia/métodos , Pasteurização , Valores de Referência , Saliva/microbiologia , Sacarose/análise , Propriedades de Superfície
2.
J Chromatogr A ; 1609: 460441, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31439440

RESUMO

A simple, rapid, and sensitive ultra-high performance liquid chromatography with charged aerosol detector (UPLC-CAD) method was developed for firstly simultaneous determination of seven oligosaccharides, including two pairs of linear oligosaccharides isomers (DP3-1, DP3-2 and DP4-1, DP4-2) and 3 high branched oligosaccharides (DP 5, 6 and 7), as well as sucrose in Pseudostellaria heterophylla. The separation was performed on a Waters BEH Amide column (2.1 × 150 mm i.d., 1.7 µm) with gradient elution within 20 min. All calibration curves for the investigated analytes showed good linearity (R2 > 0.9992). Their limits of detection (LOD) and quantification (LOQ) were in the ranges of 0.24-1.35 µg/mL and 0.78-4.96 µg/mL, respectively. Repeatability of all investigated components detected in samples was less than 2.9%. All the recoveries of each analyte ranged from 99.2% to 104.3% were acceptable. An ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometer (UPLC-QTOF MS) method was also applied to authenticate the oligosaccharides in different samples by comparing to the isolated standards. Oligosaccharides, especially linear oligosaccharides isomers and high branched oligosaccharides with different degree of polymerization (DP), were firstly identified and determined in P. heterophylla. Their contents in 33 samples of P. heterophylla from different locations was successfully compared, which is helpful to evaluate its quality.


Assuntos
Aerossóis/análise , Caryophyllaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Oligossacarídeos/análise , Sacarose/análise , Espectrometria de Massas em Tandem/métodos , Calibragem , Análise por Conglomerados , Limite de Detecção , Análise de Componente Principal , Padrões de Referência , Análise de Regressão , Reprodutibilidade dos Testes , Solventes/química , Fatores de Tempo
3.
J Dairy Res ; 86(4): 477-482, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31823833

RESUMO

The work described in this Research Communication concerns the production of Dulce de leche (DL), that is a traditional product from South America obtained by concentration. Maillard reaction (MR) products are mainly responsible for the formation of color and flavor in this product. Lactose-hydrolyzed products have been developed to supply consumer demand, but this hydrolysis may affect the flavor, color, taste, texture and even some nutritional aspects of the product. We studied the influence of different levels of lactose-hydrolysis, sucrose addition and initial pH on the development of MR, appraised by the determination of 5-hydroxymethylfurfural (HMF). A process simulator with multi-monitoring system was used to produce 15 DL. Box-Behnken 33 experimental design was applied for the three factors: pH, lactose-hydrolysis level and sucrose concentration. Lipids, protein, ashes, carbohydrates, water activity, dissolved solids, colorimetric analysis and HMF (free and total) are among the physicochemical attributes and MR indicators analyzed in this work. The products showed significant differences in composition but all the values were in agreement with the literature. Moreover, higher levels of lactose hydrolysis and higher pH presented a direct relation with the development of MR, observed by an increase in coloration (lower luminosity) and more formation of HMF, both free and total. The present study expands the knowledge about DL spread made of lactose-hydrolyzed milk, allowing the food industries to produce a lactose free DL with nutritional and sensory characteristics closer to the traditional product.


Assuntos
Furaldeído/análogos & derivados , Lactose/química , Leite/química , Animais , Fenômenos Químicos , Cor , Manipulação de Alimentos/métodos , Furaldeído/química , Concentração de Íons de Hidrogênio , Hidrólise , Reação de Maillard , América do Sul , Sacarose/análise , Sacarose/química , Paladar
4.
J Food Sci ; 84(10): 2973-2982, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546291

RESUMO

The study developed traditional and light chocolate-flavor frozen dessert formulations, aimed at the general public, lactose intolerants, and vegans, and evaluated influences on quantitative sensory profiles and consumer acceptance with the replacement of sucrose by sweeteners in low-calorie versions. Twelve samples with different matrices were studied, sweetened with sucrose, sucralose, and stevia. The ideal concentration of sucrose (9%: dairy samples and 15%: vegan samples) was determined by the JAR scale. The sweetness equivalence was determined by the magnitude estimation method. The physical-chemical parameters were evaluated: pH, overrun, melting, and texture. The sensory profile evaluated through Quantitative Descriptive Analysis (QDA). The QDA data were correlated with acceptance data by partial least squares regression (PLS). The results showed that the substitution of traditional milk by lactose-free milk in the formulation did not change the characteristics of the chocolate ice cream. The use of sweeteners presented differences for milk flavor, bitter taste, bitter residual, and melting. The use of stevia extract was characterized by the presence of bitter taste, residual sweet and bitter that inhibited the perception of milk flavor, but not directly impacting the acceptance by consumers. The sucralose presented a profile closer to the sucrose, presenting lower intensity for the undesirable attributes such as bitter taste and residual bitter. There was no significant difference in the use of soy or rice protein in vegan versions, however, the use of sweeteners and body agents negatively impacted consumers' acceptance by attenuating the flavor of vegetable protein and raising gummy coating during the melting. PRACTICAL APPLICATION: This study shows the development and sensory profile of frozen chocolate desserts. Traditional and modified samples have also been produced for consumers with dietary restrictions such as vegans, vegetarians, lactose intolerants, and diabetics. Throughout the sensory and statistical analysis, it was identified how to replace sucrose by the natural glycoside sweetener of steviol, as well as the impact on the sensory profile and the acceptance of the different formulations. The results found may provide important information for researchers in food industries who need to produce frozen chocolate desserts for vegans, vegetarians, lactose intolerant, and diabetic consumers. Stevia and sucralose were good substitutes for sucrose in the formulation of frozen desserts without lactose, but not in vegan versions (with rice and soy protein).


Assuntos
Chocolate/análise , Comportamento do Consumidor , Aditivos Alimentares/análise , Alimentos Congelados/análise , Lactose/análise , Edulcorantes/análise , Adulto , Animais , Doces/análise , Diterpenos de Caurano/análise , Feminino , Aromatizantes/análise , Análise de Alimentos , Humanos , Sorvetes/análise , Masculino , Stevia/química , Sacarose/análogos & derivados , Sacarose/análise , Paladar , Veganos , Adulto Jovem
5.
J Food Sci ; 84(9): 2628-2637, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31441950

RESUMO

Several factors have led to an increase in the consumption of sweeteners in substitution of sucrose. Studies on the behavior and the sensory properties of sweeteners are relevant, once they provide knowledge about both the adequate sweetener concentration with a sweetness equivalence to a sucrose-sweetened product and the possible sensory changes of the product. The addition of stevia with different rebaudioside A concentrations and sucralose to traditional and decaffeinated espresso coffee was studied, using the just-about-right scale and magnitude estimation method, to determine the ideal sweetness and the acceptance of the samples. The effect of the intensity of sensory attributes sweet taste, bitter taste, coffee flavor, and body in the acceptance was evaluated by penalty analysis. Decaffeinated presented proportionally lower sucrose concentration and sweetness equivalence than the traditional samples. Stevia concentrations were similar, despite the different rebaudioside A concentrations, for both traditional and decaffeinated samples, and rebaudioside A levels from stevia in espresso have no differences in sweetness intensity. Sucralose was the most intense sweetener in espresso. Although no differences were observed in the acceptance test in relation to appearance, aroma, and texture among the samples, the internal preference map showed segmentation of consumers with respect to the acceptability. This segmentation is more related to the type of sample than the added sweetener. Penalty analysis demonstrated that the most penalizing sensory characteristics were "coffee flavor" and "sweet," leading to a significant decrease in the acceptability of the samples. PRACTICAL APPLICATION: Conclusions obtained are important source of knowledge for the coffee industry, in the development and manufacture of beverages with coffee. The present findings can help to understand the behavior and the sensory properties of sweeteners. They provide knowledge about sensory perception of sweet and bitter tastes, and the factors that influence this perception and the sensory profile of the samples, once the behavior of sweeteners varies according to the product to which they are added.


Assuntos
Café/química , Preferências Alimentares , Edulcorantes/análise , Adulto , Diterpenos de Caurano/análise , Feminino , Glucosídeos/análise , Humanos , Masculino , Pessoa de Meia-Idade , Sacarose/análise , Paladar , Adulto Jovem
6.
J Dairy Res ; 86(3): 337-340, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31385560

RESUMO

The aim of this work was to use X-ray diffraction to identify substances used for adulteration of raw milk and to determine if crystallographic analysis can detect extraneous substances in milk. Two unknown substances were sent anonymously by employers linked to the dairy chain, who claimed that they were added directly in milk prior to water addition by truck drivers. The samples were analyzed by X-ray diffraction and submitted to physicochemical analysis. The first substance was identified by X-ray diffraction as sodium citrate, complying with its physicochemical attributes, such as the powerful ability to decrease the freezing point. The second substance was identified by X-ray diffraction as sucrose and this result was also in agreement with its ability to increase the density, decrease the freezing point and finally, to be positive for sucrose in the resorcinol qualitative test. To evaluate if X-ray diffraction can detect extraneous substances already mixed in milk, fresh raw milk samples tampered with urea, sodium hydroxide, sodium citrate and sucrose were freeze dried and analyzed by X-ray diffraction, with no detection of any extraneous substances at any percentage. This is the first report of attempted diagnosis of extraneous substances in milk by X-ray diffraction. However, this technique can be useful only when applied to identify substances used for adulteration prior to its dilution in milk, since the amorphous nature of milk seems to be a limitation for the accurate detection of extraneous substances.


Assuntos
Cristalografia por Raios X/veterinária , Contaminação de Alimentos/análise , Leite/química , Animais , Bovinos , Fenômenos Químicos , Citrato de Sódio/análise , Sacarose/análise , Água/análise
7.
Mar Pollut Bull ; 146: 711-717, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426213

RESUMO

Narragansett Bay is an urban estuary that historically has been impacted by long-term discharge of sanitary wastewater (WW) effluents. High-density water sampling was conducted in Narragansett Bay, RI, USA, in an effort to understand the distribution and behavior of sucralose, an artificial sweetener that has shown utility as a sanitary wastewater tracer. Water samples were collected at sixty-seven sites and analyzed for sucralose, whose performance was compared to other tracers present in wastewater effluents. Concentrations of sucralose were much higher than the other tracers measured, carbamazepine and caffeine, ranging from 18 to 3180 ng/L and corresponded well with salinity (r2 = 0.88), demonstrating conservative behavior throughout the Bay. Mapped interpolation data using an empirical bayesian kriging model clearly show the spatial trends of WW and how estuarine processes influence dilution and dispersion throughout the Bay. These findings provide further evidence of the efficacy of sucralose as a wastewater tracer in large urban estuaries where continuous high-volume discharge of WW occur.


Assuntos
Monitoramento Ambiental/métodos , Sacarose/análogos & derivados , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Teorema de Bayes , Baías , Cafeína/análise , Estuários , Hidrologia/métodos , Rhode Island , Salinidade , Sacarose/análise , Edulcorantes/análise
8.
Food Chem ; 299: 125122, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31288165

RESUMO

To ease the mass exchange in fruit tissues, cutting and blanching are traditionally performed. However, recently, unconventional methods such as sonication are becoming more popular, which cause several alterations of physical and chemical properties as well as microstructure changes. The aim of this work was to evaluate the distribution of water inside the cranberry fruits, microstructural changes and sugars content, following traditional and sonication pre-treatments in osmotic solutions. TD-NMR spectroscopy was used to measure the transverse relaxation time (T2) and intensity of proton pools in different cellular compartments. The microstructure of the samples was evaluated by SEM microscopy, sugars content by HPLC and sucrose melting temperature and enthalpy by DSC. Different pre-treatments appeared to promote microstructure alterations and loss of water from vacuole and cytoplasm/extracellular space, more pronounced in cut and blanched samples. Cutting and blanching followed by osmotic dehydration with assisted sonication eased sucrose penetration into the tissue.


Assuntos
Conservação de Alimentos/métodos , Frutas/química , Açúcares/análise , Vaccinium macrocarpon/química , Água/metabolismo , Varredura Diferencial de Calorimetria , Dessecação , Frutas/ultraestrutura , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Osmose , Sonicação , Sacarose/análise , Temperatura , Vaccinium macrocarpon/ultraestrutura
9.
BMC Res Notes ; 12(1): 460, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349864

RESUMO

OBJECTIVE: Excipients are needed in the formulation of oral liquid medicines intended for children; they have however been reported to trigger safety issues. This study evaluated the concentrations and prevalence of ethanol and other potentially harmful excipients in pediatric formulations marketed in South Eastern Nigeria in line with international labeling guidelines and allowable daily limits (ADL). The study sampled oral pediatric formulations offered for sale in registered pharmacies. Those with accessible information leaflets were assessed for the presence and quantity of previously flagged excipients with potential to harm the pediatric population. RESULT: Of the 380 oral pediatric medicines, 140 provided access to list/quantity of ingredients. 47.9% (67) of the formulations contain at least one of the flagged excipients while the remaining only listed the active ingredients. Ethanol had the highest occurrence (62.7%) and was more in cough/cold medicines. A homeopathic cough and cold remedy had concentration of 90% v/v. Ethanol and sucrose in some formulations exhibited concentrations with a potential of crossing their approved daily intake (ADI) (1-90% v/v and 1.7 g-3.7 g/5 ml respectively). Ethanol use in studied pediatric formulations was quite high, with ethanol-containing formulations being prescribed for children 0-6 years and older. Only 26 (38.8%) completely satisfied the labelling requirements for ethanol containing formulations.


Assuntos
Formas de Dosagem , Etanol/análise , Excipientes/análise , Farmácias/ética , Administração Oral , Aspartame/análise , Compostos Azo/análise , Criança , Humanos , Nigéria , Parabenos/análise , Polissorbatos/análise , Propilenoglicol/análise , Sacarina/análise , Benzoato de Sódio/análise , Sorbitol/análise , Sacarose/análise , Inquéritos e Questionários
10.
Talanta ; 203: 235-241, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202332

RESUMO

According to European Union regulations, honey is a pure product and adding to or removing from it any kind of substance is illegal. Nevertheless, its adulteration by adding inexpensive and artificial adulterants is a common practice. This paper deals with the use of visible and near-infrared spectroscopy (Vis-NIRS) combined with chemometric tools as a screening technique for the identification and quantification of different types of adulterants (inverted sugar, rice syrup, brown cane sugar and fructose syrup) added to high-quality honey (Granada Protected Designation of Origin, Spain) at different levels (5%-50%). A complete discrimination between non-adulterated and adulterated samples was achieved. A general regression model to quantify the adulteration levels was developed as well as specific models for each adulterant. The coefficients of determination were higher than 0.96 for all the models. These results demonstrate the capacity of Vis-NIRS combined with chemometric tools for honey quality control.


Assuntos
Contaminação de Alimentos/análise , Mel/análise , Frutose/análise , Glucose/análise , Análise Multivariada , Oryza/química , Saccharum/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Sacarose/análise
11.
Environ Sci Pollut Res Int ; 26(19): 19241-19249, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31065989

RESUMO

Nitrate excess is common in greenhouse soils, imposing environmental risks and degrading vegetable quality. In this study, the effectiveness of adding sucrose as available carbon through irrigation to cut nitrate excess in lettuce-planted soil was investigated under impacts of soil texture and irrigation type. In the pot experiment using two loam soils of same origin with different clay to sand ratios (50.2% and 39.8%) and nitrate excess (116.1 and 417.7 mg/kg N), three-time sucrose addition through flood irrigation was more effective in lowering net formation of nitrate-based inorganic N and increasing lettuce yield in the soil with the higher clay to sand ratio, and sucrose addition at 150-450 mg/kg reduced nitrate accumulation and leaching, and nitrate content of lettuce at harvest by 62.5-89.6%, 19.3-36.1%, and 11.4-76.0%, respectively. In the micro-plot field experiment with two-time sucrose addition at 0.6-1.2 g/L through furrow irrigation (42 mm) into two other soils of same origin with different clay to sand ratios (56.9%, 48.4%), nitrate accumulation at 0-30-cm depth at the prone-leaching furrow location at harvest decreased by 30.9-36.0% under the higher clay to sand ratio but increased by about 35% under the lower clay to sand ratio. The nitrate content and yield of ridge-planted lettuce was less affected in either soil. Hence, carbon addition rate, irrigation type, and clay to sand ratio all affected the effect of available carbon addition on nitrate accumulation in vegetable-planted soil, and their joint impacts need better quantification for cutting nitrate excess in soil and improving vegetable quality and even yield.


Assuntos
Irrigação Agrícola , Produção Agrícola/métodos , Alface/química , Nitratos/análise , Solo/química , Sacarose/análise , Biomassa , Alface/normas
12.
J Sci Food Agric ; 99(12): 5526-5532, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31102411

RESUMO

BACKGROUND: Trisodium phosphate (TSP), generally recognized as safe (GRAS), could control postharvest diseases and maintain fruit quality. However, changes of fruit quality and sucrose metabolism in harvested jujube after TSP treatment remain largely unknown. In the current study, jujube fruit (cv. sanxing) was used to study the effects of TSP on storage quality and sucrose metabolism during storage at 20 ± 2 °C with 40-50% relative humidity (RH). RESULTS: The results showed that 0.5 g L-1 TSP treatment reduced weight loss and reduced sugar content, suppressed the reduction of fruit firmness, maintained ascorbic acid (AsA) content and inhibited respiratory rate of jujube fruit. In addition, TSP treatment also reduced acid invertase (AI) and neutral invertase (NI) activities in sucrose metabolism in jujube fruit. Sucrose synthase-cleavage (SS-c), sucrose synthase-synthesis (SS-s) and sucrose phosphate synthase (SPS) activities were also suppressed by TSP treatment. CONCLUSION: Treatment with TSP could effectively reduce enzymes activities in sucrose metabolism and maintain storage quality of jujube fruit during storage. © 2019 Society of Chemical Industry.


Assuntos
Conservantes de Alimentos/farmacologia , Frutas/química , Fosfatos/farmacologia , Ziziphus/efeitos dos fármacos , Conservação de Alimentos , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Glucosiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Controle de Qualidade , Sacarose/análise , Ziziphus/química
13.
J Agric Food Chem ; 67(17): 5043-5052, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30977368

RESUMO

The low phytic acid ( lpa) soybean ( Glycine max L. Merr.) mutant Gm-lpa-TW-1-M, resulting from a 2 bp deletion in GmMIPS1, was crossed with a commercial cultivar. F3 and F5 progenies were subjected to nontargeted GC-based metabolite profiling, allowing analysis of a broad array of low molecular weight constituents. In the homozygous lpa mutant progenies the intended phytic acid reduction was accompanied by remarkable metabolic changes of nutritionally relevant constituents such as reduced contents of raffinose oligosaccharides and galactosyl cyclitols as well as increased concentrations in sucrose and various free amino acids. The mutation-induced metabolite signature was nearly unaffected by the cross-breeding and consistently expressed over generations and in different growing seasons. Therefore, not only the primary MIPS1 lpa mutant but also its progenies might be valuable genetic resources for commercial breeding programs to produce soybean seeds stably exhibiting improved phytate-related and nutritional properties.


Assuntos
Proteínas de Arabidopsis/genética , Mio-Inositol-1-Fosfato Sintase/genética , Ácido Fítico/análise , Proteínas de Plantas/genética , Soja/enzimologia , Proteínas de Arabidopsis/metabolismo , Homozigoto , Hibridização Genética , Mutação , Mio-Inositol-1-Fosfato Sintase/metabolismo , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Ácido Fítico/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Rafinose/análise , Rafinose/metabolismo , Soja/química , Soja/genética , Soja/metabolismo , Sacarose/análise , Sacarose/metabolismo
14.
Planta ; 250(1): 263-279, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31020407

RESUMO

MAIN CONCLUSION: Sugars (glucose, fructose and sucrose), as well as proteogenic and non-proteogenic amino acids, are present in the nectar of Platanthera bifolia and P. chlorantha. Nectar quantity and quality are floral traits that are subjected to pollinator-mediated selection. Nectar sugar and amino acid (AA) composition in two sister species, P. bifolia and P. chlorantha, was analysed and the interspecies differences in nectar and the importance of these nectar characteristics for reproductive success were investigated. Nectar was collected from four P. bifolia and three P. chlorantha populations that exist in different habitats in three regions of NE Poland. Nectar from about 30 flowers (from each population) was sampled and analysed using high-performance liquid chromatography. We found the same primary sugars and AA components in the nectar of both species, although their content varied between the populations according to habitat properties. The nectar of P. bifolia and P. chlorantha both had low sugar concentrations (9.04-20.68%) and were dominated by hexoses, with sucrose:hexoses ratios between 0.03 and 0.31 across the different populations (the average for the P. bifolia populations was 0.17 and the average for the P. chlorantha populations was - 0.05). Total sugar content did not influence reproductive success and we found positive selection on fructose content. In general, 23 different AAs were detected in both Platanthera species. Cysteine and γ-aminobutyric acid were present in only one population of P. chlorantha. Sarcosine dominated among the non-proteogenic AAs. To our knowledge, this is the first report that characterizes the sugar and AA profiles in the nectar of P. bifolia and P. chlorantha in natural populations in the context of effectiveness of reproduction. Total AAs negatively influenced male reproductive success (r = - 0.79). Pollinators of the investigated species were found to be sensitive to the AAs' taste, from taste classes I and IV. Correlation between male reproductive success and the content of AAs from these groups was 0.79 in both cases. In this manuscript, we investigated the characteristics of P. bifolia and P. chlorantha nectar, and compared these characteristics to the available data in the context of their adaptations to the requirements of pollinators and with regard to the importance of nectar quality for reproductive success of the studied species.


Assuntos
Mariposas/fisiologia , Orchidaceae/química , Néctar de Plantas/química , Aminoácidos/análise , Animais , Ecossistema , Flores/química , Flores/fisiologia , Frutose/análise , Glucose/análise , Orchidaceae/fisiologia , Néctar de Plantas/fisiologia , Polônia , Polinização , Reprodução , Sacarose/análise
15.
J Agric Food Chem ; 67(16): 4595-4602, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30907589

RESUMO

Aflatoxin B1 (AFB1), is a type I carcinogen that is one of the strongest naturally occurring aflatoxins and can be injurious to humans and livestock upon ingestion, inhalation, or skin contact, with carcinogenic and mutagenic effects. It causes significant hazardous effects to the food- and animal-production industries. We found a bacterial strain, 3J2MO, that degraded AFB1 well, and here we tested and characterized its AFB1-degradation ability. The strain degraded about 93.82% of the AFB1 after incubation for 48 h in Luria-Bertani (LB) medium at 37 °C with a final concentration of 100 ppb and an inoculation quantity of 1 × 107 cfu/mL. High-performance liquid chromatography-fluorescence detection (HPLC-FLD) was used to determine AFB1 amounts. The maximum degradation rates were 89.23% at pH 8.5; 55.78% at an inoculation quantity of 1 × 108 cfu/mL; and 71.50 and 71.21% at 34 and 37 °C, respectively. Treatment with sucrose and soluble starch as carbon sources and beef extract and ammonium acetate as nitrogen sources stimulated the degradation rate. Mg2+ and Ca2+ ions were activators for AFB1 degradation; however, Mn2+, Fe3+, Zn2+, and Cu2+ were strong inhibitors. This bacterial strain has potential in bioremediation and the detoxification of aflatoxin contamination for biocontrol strategies in both agricultural products and food-industry matrices.


Assuntos
Aflatoxina B1/metabolismo , Flavobacteriaceae/metabolismo , Aflatoxina B1/análise , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Meios de Cultura/química , Meios de Cultura/metabolismo , Flavobacteriaceae/química , Concentração de Íons de Hidrogênio , Sacarose/análise , Sacarose/metabolismo
16.
Chemosphere ; 220: 629-636, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30599320

RESUMO

Urban estuaries receive large volumes of effluents from municipal wastewater treatment facilities containing numerous contaminants, such as pharmaceuticals residues. Water was sampled for 16 highly prescribed pharmaceuticals at 17 sites along the Long Island Sound (LIS) estuary located in the Northeastern U.S. Pharmaceutical concentrations were highest in western LIS, ranging from non-detect to 71 ng L-1 and declining steadily eastward, while river samples from four major tributaries ranged from non-detect to 83 ng L-1. Two tracers, sucralose and caffeine, accurately predicted pharmaceutical behavior in LIS while only sucralose was effective at the river sites. Sucralose also tracked well with the salinity gradient in LIS, exhibiting conservative behavior along the transect. Attenuation factors were determined for measurable pharmaceuticals and compared against sucralose to estimate the magnitude of decline in concentrations that may be attributable to in situ degradation and partitioning. The results demonstrate sucralose's effectiveness as a tracer of wastewater-borne contaminants under estuarine conditions.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Preparações Farmacêuticas/análise , Sacarose/análogos & derivados , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Cafeína , Rios/química , Salinidade , Sacarose/análise , Estados Unidos , Águas Residuárias/química
17.
Plant Sci ; 278: 107-112, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471723

RESUMO

To confirm availability of Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry imaging (MSI) for visualizing distribution of soluble carbohydrates in apple (Malus domestica) fruits a horizontal fruit flesh specimen was cut from a matured 'Fuji' fruit, mounted on a glass slide, lyophilized and then ion intensities of individual soluble carbohydrates were probed around the specimen using a MALDI-TOF MSI apparatus automatically. Contents of soluble carbohydrates in adjacent tissue of the same fruit were also determined using HPLC to compare the distribution of individual carbohydrate based on the ion intensities from MALDI-TOF MSI with those from HPLC. Positive correlation (P < 0.001, R2 > 0.95) was confirmed between the concentration of each standard carbohydrate and the relative ion intensity of MALDI-TOF mass spectrometry (MS), and thus it seems possible to use the ion intensity of MALDI-TOF MS for determining the relative concentration of carbohydrates in a sample. Singly charged ions attached with a potassium ion only were detected from the apple fruit specimen when DHB was used as a matrix for MALDI-TOF MSI. Graded increase of sucrose content from center to cortex side of the fruit flesh was confirmed by both MALDI-TOF MSI and HPLC. When pseudo color images on the distribution of individual carbohydrates based on the results from MALDI-TOF MSI were compared with the content of carbohydrates in the adjacent 16 tissue blocks quantified using HPLC, strong (P < 0.001, R2 = 0.6222) and weak (P < 0.10, R2 = 0.2123) correlation was confirmed between the brightness and the content of sucrose and sorbitol, respectively. These facts indicate that distribution of sucrose and sorbitol in apple fruit tissue can be visualized using MALDI-TOF MSI. Thus, MALDI-TOF MSI will be useful for examining carbohydrate metabolism during the maturing of apple fruit.


Assuntos
Carboidratos/análise , Malus/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cromatografia Líquida de Alta Pressão , Frutas/metabolismo , Sorbitol/análise , Sorbitol/metabolismo , Sacarose/análise , Sacarose/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-30359850

RESUMO

Rind biochemical properties play major roles in defence mechanisms against the incidence of rind physiological disorders of citrus fruit during cold storage. Hence, multivariate calibration models were developed to rapidly and non-destructively determine rind biochemical properties of citrus fruit from visible to near-infrared (Vis/NIR) spectra acquired by Vis/NIR spectroscopy using partial least square regression algorithm. To achieve optimum models for determination of each rind biochemical property, several mathematical pre-processing methods were explored, including no pre-treatment. However, special emphases were given to the best model statistics in terms of coefficient of determination (R2) and residual predictive deviation (RPD). Models were performed by critical examination of different wavelength ranges (visible, near-infrared and full regions) and combinations of fruit harvested from different production regions and acquired before (week 0) and after (week 9) cold storage. Results obtained showed excellent models for determining parameters such as sucrose (R2 = 0.99 and RPD = 11.42), total flavonoids (R2 = 0.99 and RPD = 12.37), and chlorophyll b (R2 = 0.97 and RPD = 5.67). This study reported the first application of Vis/NIR and chemometrics in determining the rind biochemical properties of 'Marsh' grapefruit rapidly and non-destructively.


Assuntos
Clorofila/análise , Citrus paradisi/química , Flavonoides/análise , Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Sacarose/análise , Áreas Alagadas
19.
J Pharm Biomed Anal ; 164: 365-372, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30439664

RESUMO

Vitis vinifera grape is a highly cultivated crop and solid wastes generated by the wine industry are largely under exploited. Plentiful studies have intended analyzing the polyphenolic content of grape seeds but characterization of non phenolic compounds is rather scarce. The present study aimed at the selective extraction of lipid, phenolic and aqueous phases from grape seed powder (GSP) in order to establish their intimate composition, as well as their antioxidant and chelating properties underlying partly their biological effects. Major non phenolic compounds identified in the lipid phase were glyceryl-monostearate and 2-monostearin whereas fructofuranose and sucrose were the most abundant in the aqueous phase. Among the most abundant compounds detected in the various phases, the polyphenol quercetin exhibited the best affinity and free binding energy towards the active site of the calcium-dependent protease calpain. Polyphenols likely constitute the bioactive part of GSP that should be exploited as safe modulators of intracellular signaling which is likely at the basis of their health beneficial effects. Nevertheless other compounds as lipids or sugars should be valorized along with polyphenols to improve their bioavailability into highly protected organs as brain or eye.


Assuntos
Antioxidantes/farmacologia , Calpaína/antagonistas & inibidores , Extrato de Sementes de Uva/farmacologia , Vitis/química , Antioxidantes/análise , Antioxidantes/química , Calpaína/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Glicerídeos/análise , Glicerídeos/química , Glicerídeos/farmacologia , Extrato de Sementes de Uva/análise , Extrato de Sementes de Uva/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estresse Oxidativo , Polifenóis/análise , Polifenóis/química , Polifenóis/farmacologia , Pós , Sementes/química , Sacarose/análise , Sacarose/química , Sacarose/farmacologia
20.
Food Chem ; 274: 434-443, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30372962

RESUMO

Chlorine treatment increases the surface hydrophobicity of starch granules of soft wheat flour and reduces its gluten network forming capacity and apparent content of the flour lipids, the latter presumably by forming chlorinated derivatives. It also increases its solvent holding capacity as shown by proton nuclear magnetic resonance (1H NMR) experiments in presence of sucrose. The exchanging protons in the extra-granular space are present in an environment with restricted mobility, indicating strong interactions between chlorinated soft wheat flour (CSWF) components and solvent. Chlorination reduced the capability of free flour lipids to shield starch granules during rapid visco analysis (RVA). The higher viscosity reached in RVA with CSWF was attributed to not only its lipids having different properties but also its protein, resulting in improved starch swelling and amylose leaching. Finally, 1H NMR indicated that starch and protein networks in CSWF-sucrose gels were better structured than in gels prepared from non-chlorinated flour.


Assuntos
Cloro/química , Farinha/análise , Sacarose/análise , Triticum/química , Amilose/análise , Viscosidade
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