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1.
Anal Bioanal Chem ; 416(19): 4409-4415, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38864917

RESUMO

We present a novel approach for iodide sensing based on the heavy-atom effect to quench the green fluorescent emission of organosilicon nanoparticles (OSiNPs). The fluorescence of OSiNPs was significantly quenched (up to 97.4% quenching efficiency) in the presence of iodide ions (I-) through oxidation by hydrogen peroxide. Therefore, OSiNPs can serve as a fluorescent probe to detect I- with high selectivity and sensitivity. The highly selective response is attributed to the hydrophilic surface enabling good dispersion in aqueous solutions and the lipophilic core allowing the generated liposoluble I2 to approach and quench the fluorescence of OSiNPs. The linear working range for I- was from 0 to 50 µM, with a detection limit of 0.1 µM. We successfully applied this nanosensor to determine iodine content in edible salt. Furthermore, the fluorescent OSiNPs can be utilized for the determination of total antioxidant capacity (TAC). Antioxidants reduce I2 to I-, and the extent of quenching by the remaining I2 on the OSiNPs indicates the TAC level. The responses to ascorbic acid, pyrogallic acid, and glutathione were investigated, and the detection limit for ascorbic acid was as low as 0.03 µM. It was applied to the determination of TAC in ascorbic acid tablets and fruit juices, indicating the potential application of the OSiNP-based I2 sensing technique in the field of food analysis.


Assuntos
Antioxidantes , Corantes Fluorescentes , Iodetos , Limite de Detecção , Nanopartículas , Iodetos/análise , Iodetos/química , Nanopartículas/química , Antioxidantes/análise , Antioxidantes/química , Corantes Fluorescentes/química , Compostos de Organossilício/química , Espectrometria de Fluorescência/métodos , Ácido Ascórbico/análise , Sucos de Frutas e Vegetais/análise
2.
Int J Food Microbiol ; 418: 110731, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38733637

RESUMO

Alicyclobacillus spp. is the cause of great concern for the food industry due to their spores' resistance (thermal and chemical) and the spoilage potential of some species. Despite this, not all Alicyclobacillus strains can spoil fruit juices. Thus, this study aimed to identify Alicyclobacillus spp. strains isolated from fruit-based products produced in Argentina, Brazil, and Italy by DNA sequencing. All Alicyclobacillus isolates were tested for guaiacol production by the peroxidase method. Positive strains for guaiacol production were individually inoculated at concentration of 103 CFU/mL in 10 mL of orange (pH 3.90) and apple (pH 3.50) juices adjusted to 11°Brix, following incubation at 45 °C for at least 5 days to induce the production of the following spoilage compounds: Guaiacol, 2,6-dichlorophenol (2,6-DCP) and 2,6-dibromophenol (2,6-DBP). The techniques of micro-solid phase extraction by headspace (HS-SPME) and gas-chromatography with mass spectrometry (GC-MS) were used to identify and quantify the spoilage compounds. All GC-MS data was analyzed by principal component analysis (PCA). The effects of different thermal shock conditions on the recovery of Alicyclobacillus spores inoculated in orange and apple juice (11°Brix) were also tested. A total of 484 strains were isolated from 48 brands, and the species A. acidocaldarius and A. acidoterrestris were the most found among all samples analyzed. In some samples from Argentina, the species A. vulcanalis and A. mali were also identified. The incidence of these two main species of Alicyclobacillus in this study was mainly in products from pear (n = 108; 22.3 %), peach (n = 99; 20.5 %), apple (n = 86; 17.8 %), and tomato (n = 63; 13 %). The results indicated that from the total isolates from Argentina (n = 414), Brazil (n = 54) and Italy (n = 16) were able to produce guaiacol: 107 (25.8 %), 33 (61.1 %) and 13 (81.2 %) isolates from each country, respectively. The PCA score plot indicated that the Argentina and Brazil isolates correlate with higher production of guaiacol and 2,6-DCP/2,6-DBP, respectively. Heatmaps of cell survival after heat shock demonstrated that strains with different levels of guaiacol production present different resistances according to spoilage ability. None of the Alicyclobacillus isolates survived heat shocks at 120 °C for 3 min. This work provides insights into the incidence, spoilage potential, and thermal shock resistance of Alicyclobacillus strains isolated from fruit-based products.


Assuntos
Alicyclobacillus , Sucos de Frutas e Vegetais , Frutas , Cromatografia Gasosa-Espectrometria de Massas , Guaiacol , Esporos Bacterianos , Alicyclobacillus/isolamento & purificação , Alicyclobacillus/genética , Alicyclobacillus/classificação , Alicyclobacillus/crescimento & desenvolvimento , Sucos de Frutas e Vegetais/microbiologia , Guaiacol/análogos & derivados , Guaiacol/metabolismo , Guaiacol/farmacologia , Frutas/microbiologia , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/isolamento & purificação , Microbiologia de Alimentos , Contaminação de Alimentos/análise , Brasil , Microextração em Fase Sólida , Argentina , Malus/microbiologia , Itália , Temperatura Alta , Citrus sinensis/microbiologia
3.
Food Chem Toxicol ; 181: 114082, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783419

RESUMO

European cranberrybush (ECB) (Viburnum opulus L.) fruits are abundant in phenolic compounds associated with various health benefits. However, the toxicity and safety of ECB juice have not been systematically studied. In the present study, acute and subacute oral toxicities of ECB fruit juice were evaluated on Sprague-Dawley rats and BALB/c mice to establish a toxicity profile. In acute tests, a single administration of 2000 mg/kg body weight of extract to rats exhibited no clinical signs of toxicity or mortality, indicating that the lethal dose (LD50) was over 2000 mg/kg. In subacute tests, repeated administration for 28 days at 0 (control), 500, and 2000 mg/kg doses of extract in mice did not display adverse clinical signs or deaths. However, in the 2000 mg/kg subacute group, platelet counts were significantly high, which correlated with histopathological analyses revealing that ECB extract at 2000 mg/kg was toxic to the kidney, liver, and adipose tissue. The NOAEL value of ECB extract was found as 500 mg/kg/day, but further sub-chronic and chronic toxicity studies are warranted to comprehensively evaluate the long-term safety implications. The study's results emphasize the importance of considering the dosage of dietary supplements containing high levels of phenolic compounds over an extended period to avoid potential cumulative effects from prolonged consumption of high doses.


Assuntos
Extratos Vegetais , Viburnum , Ratos , Camundongos , Animais , Ratos Sprague-Dawley , Extratos Vegetais/toxicidade , Sucos de Frutas e Vegetais , Frutas , Fenóis/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
4.
J Appl Physiol (1985) ; 135(5): 1167-1175, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37732374

RESUMO

Oral inorganic nitrate (NO3-) supplementation has been shown to increase bioavailable NO and provide potential ergogenic benefits in males; however, data in females is scarce. Estrogen is known to increase endogenous NO bioavailability and to fluctuate throughout the menstrual cycle (MC), being lowest in the early follicular (EF) phase and highest during the late follicular (LF) phase. This study examined the effects of oral NO3- supplementation on exercise economy, endurance capacity, and vascular health in young females across the MC. Ten normally menstruating females' MCs were tested in a double-blinded, randomized design during both the EF and LF phases of the MC. Participants consumed ∼13 mmol NO3-, in the form of 140 mL beetroot juice (BRJ) or an identical NO3--depleted placebo (PL) for ∼3 days before lab visits and 2 h before testing on lab visits. Plasma nitrate, nitrite, and estradiol were assessed, as was blood pressure and pulse wave velocity. Moderate-intensity exercise economy and severe intensity time to exhaustion (TTE) were tested on a cycle ergometer. As expected, plasma estradiol was elevated in the LF phase, and plasma nitrite and nitrate were elevated in the BRJ condition. Exercise economy was unaltered by BRJ or the MC, however TTE was significantly worsened by 48 s (∼10%) after BRJ supplementation (P = 0.04), but was not different across the MC with no interaction effects. In conclusion, NO3- supplementation did not affect exercise economy or vascular health and worsened aerobic endurance capacity (TTE), suggesting healthy females should proceed with caution when considering supplementation with BRJ.NEW & NOTEWORTHY Although inorganic nitrate (NO3-) supplementation has increased in popularity as a means of improving exercise performance, data in females at different phases of the menstrual cycle are lacking despite known interactions of estrogen with NO. This study revealed neither NO3- supplementation nor the menstrual cycle influenced exercise economy or vascular health in healthy young naturally menstruating females, while NO3- supplementation significantly worsened endurance capacity (10%) independent of the menstrual cycle phase.


Assuntos
Beta vulgaris , Nitratos , Feminino , Humanos , Masculino , Antioxidantes , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Estradiol , Estrogênios , Sucos de Frutas e Vegetais , Ciclo Menstrual , Nitritos , Análise de Onda de Pulso
5.
Food Chem Toxicol ; 173: 113633, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36724847

RESUMO

A high variety of food contains low doses of ethanol which are sometimes difficult to identify by consumers (adults or children). However, even low doses of ethanol intake raises several toxicological concerns. In the present study, an enzymatic assay and an HS-GC/MS procedure were applied to determine the ethanol levels of 1260 samples from different food categories covering "nonalcoholic" beer, fruit juices/drinks, baked goods, bananas and baby foods. Based on these results, ethanol levels resulting from acute or chronic ethanol intake was calculated using consumption data from the EFSA Comprehensive European Food Consumption Database. Thus, health-based guidance values (HBGV) for ethanol intake were derived for acute or chronic exposure based on the available literature. For acute exposure, very few samples resulted in concerning ethanol uptake levels but following chronic exposure the here derived HBGV level was exceeded in several cases. This is mainly due to the following reasons: (1) certain amounts of ethanol are still tolerated in "nonalcoholic" beer and (2) presence of endogenous produced ethanol in bananas or baked goods via fermentation. Most analysed food samples, however, do not result in elevated ethanol doses linked with a potentially high risk following acute and chronic consumption by adults and children.


Assuntos
Bebidas , Etanol , Criança , Adulto , Humanos , Alimentos Infantis , Sucos de Frutas e Vegetais , Medição de Risco
6.
Environ Sci Pollut Res Int ; 30(15): 44833-44844, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36701052

RESUMO

In the present study, magnetic solid phase extraction (MSPE) method and gas chromatography-mass spectrometry (GC/MS) technique were used to measure 6 PAE in fruit juice samples. The mean of total phthalic acid esters (Æ©PAEs) in all samples was 3.55 ± 0.66 µg/L. The mean concentration of DEHP (bis(2-ethylhexyl) phthalate) in samples was 0.82 ± 0.31 µg/L, which was lower than the mentioned United States Environmental Protection Agency (USEPA) standard level in drinking water (6 µg/L for DEHP). The pineapple juice samples (4.44 ± 0.57 µg/L) and mango juice samples (2.77 ± 0. 1 µg/L) had maximum and minimum mean levels of Æ©PAEs, respectively. Also, results showed that brand B (3.76 ± 0.87 µg/L) and samples in the time of expiration date (3.64 ± 0.72 µg/L) had the highest PAE levels. The rank order Chronic Daily Intake (95%) values for adults were DEHP ([Formula: see text]) > butylbenzyl phthalates (BBP) ([Formula: see text]) > diethyl phthalate (DEP) ([Formula: see text]) and for children were DEHP ([Formula: see text]) > BBP (9.07E-04) > DEP ([Formula: see text]), which were below the tolerable daily intake (TDI) value. The noncancer risk of PAEs based on the target hazard quotient (THQ) was acceptable (< 1). The results exhibited that the Incremental Lifetime Cancer Risk (ILCR) was below the permissible limit (< [Formula: see text]). Therefore, the risk of carcinogenicity and noncarcinogenicity of PAEs in juices does not have adverse effects on human health.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Criança , Adulto , Humanos , Sucos de Frutas e Vegetais/análise , Irã (Geográfico) , Dietilexilftalato/análise , Ácidos Ftálicos/análise , Medição de Risco , Ésteres/análise , Dibutilftalato/análise , China
7.
Environ Sci Pollut Res Int ; 30(8): 20077-20088, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36251183

RESUMO

The objective of the present study was to investigate the level of 16 PAHs in fruit juice samples (orange, apple, peach, pineapple, and mango) with three different packages (PET bottle, Tetra Pak, and canned packaging) by using MSPE/GC-MS (magnetic solid-phase extraction and gas chromatography-mass spectrometry) method. In this method limit of detection (LOD), and limit of quantitation (LOQ), and recovery were 0.030-0.280 µg/L, 0.090-0.840 µg/L, and 94.8-102%, respectively. Our results showed the median of total PAHs and PAH4 (in all samples) were 7.67 ± 3.19 and 0.370 ± 0.160 µg/L, respectively. The median of BaP in samples was )0.060 ± 0.030 µg/L( lower than the standard level (0.200 µg/L in drinking water) of US Environmental Protection Agency (USEPA). Also, our results showed that pineapple juice had a maximum median of total PAHs of 12.4 ± 4.84 µg/L and mango juice had a minimum median of total PAHs of 5.17 ± 1.24 µg/L. Additionally, canned packaging had a maximum average total PAHs of 10.6 ± 5.22 µg/L and PET bottles had a minimum average total PAH of 5.25 ± 2.03 µg/L. A heat map approach was also used to cluster samples. The Monte Carlo results indicated that the estimated daily intake (EDI) rank order was Na > B(g)P > Ch > I(cd)P > B(b)F > Ph > B(k)F > F > Ace > Fl > B(a)P > B(a)A > P >A. The Monte Carlo simulation (MCS) results showed the incremental lifetime cancer risk (ILCR) at the 95th percentiles for adults and children was 4.91 × 10-7 and 9.12 × 10-7, respectively. It is concluded that the concentration of PAHs compounds in Iranian fruit juices is lower than the existing standards, and in terms of the risk of carcinogenesis, it does not threaten the human health (< 10-6).


Assuntos
Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Criança , Humanos , Irã (Geográfico) , Sucos de Frutas e Vegetais/análise , Medição de Risco , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise
8.
Food Chem Toxicol ; 170: 113493, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36326503

RESUMO

The current study assessed the risk posed to Iranian consumers by oral exposure to a mixture of 20 pesticides and six metals in 96 fruit juice (FJ) samples (3 batches × 4 brands × 8 types of FJs) collected from Iran market. Concentrations of metals and pesticides in FJs were quantified by inductively coupled plasma-optical emission spectrometry (ICP-OES) and chromatography-mass spectrometry (GC-MS), respectively. The mean concentration of all pesticides was below the maximum residue limits (MRLs) set by the European Union (EU). The calculated target hazard quotients (THQs) and total hazard index (HI) were <1.0 for all pesticides residue, indicating no risk. For the carcinogenic metals (As, Ni, and Pb), estimated incremental lifetime cancer risks (ILCRs) at the 50th and 95th centiles were respectively 4.25 × 10-5 and 5.30 × 10-5 (for As), 2.85 × 10-5 and 3.71 × 10-5 (for Ni), and 2.84 × 10-8, and 3.97 × 10-8 (for Pb), indicating no risk. At the 50th and 95th centiles, HI for non-carcinogenic metals (Cd, Hg, and Cr) was <1.0, indicating no risk. Based on sensitivity analyses of the input variables, the concentration of metals and pesticides, and the FJs ingestion rate had significant influential impacts on the calculated THQ and HI.


Assuntos
Metais Pesados , Praguicidas , Metais Pesados/toxicidade , Metais Pesados/análise , Irã (Geográfico) , Sucos de Frutas e Vegetais/análise , Praguicidas/toxicidade , Praguicidas/análise , Chumbo/análise , Medição de Risco , Monitoramento Ambiental
9.
Nutrients ; 14(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35889796

RESUMO

Nitrate (NO3−) supplementation has been reported to enhance intermittent exercise performance; however, its impact on oxygen (O2) cost during intermittent running exercise is unclear. The aim of this study was to assess if acute NO3− supplementation would elicit performance benefits in recreationally active individuals during the Yo−Yo intermittent recovery level 1 (Yo-Yo IR1) test, with its potential benefit on O2 consumption (VO2), in a double-blind, randomized, crossover study, 12 recreational males consumed NO3−-rich (NIT; ~12.8 mmol), and NO3−-depleted (PLA; 0.04 mmol) concentrated beetroot juice 3 h before completing the Yo-Yo IR1 test. VO2 was measured at 160, 280 and 440 m (sub-maximal) and when the test was terminated (peak). Performance in the Yo−Yo IR1 was greater with NIT (990 ± 442.25 m) compared to PLA (870 ± 357.4 m, p = 0.007). The VO2 was not significantly different at 160 m (1.92 ± 0.99 vs. 2.1 ± 0.88 L·min−1), 280 m (2.62 ± 0.94 vs. 2.83 ± 0.94 L·min−1), 440 m (3.26 ± 1.04 vs. 3.46 ± 0.98 L·min−1) and peak (4.71 ± 1.01 vs. 4.92 ± 1.17 L·min−1) between NIT and PLA trials (all p > 0.05). The present study has indicated that acute supplementation of NO3− enhanced intermittent running performance but had no effect on VO2 during the Yo−Yo IR1 test in recreational young adults.


Assuntos
Beta vulgaris , Corrida , Antioxidantes , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Sucos de Frutas e Vegetais , Humanos , Masculino , Nitratos , Oxigênio , Consumo de Oxigênio , Poliésteres , Adulto Jovem
10.
Molecules ; 27(12)2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35745056

RESUMO

The high consumption of plant-based foods on a global scale has increased the number of adulterations in the food industry. Along with this, analytical approaches to fraud detection need to be further developed. A nontargeted effect-directed profiling by high-performance thin-layer chromatography hyphenated with five effect-directed assays (free radical scavenging assay, Aliivibrio fischeri bioassay, and acetylcholinesterase, butyrylcholinesterase, and tyrosinase inhibition assays) and multi-imaging provided additional information on the antioxidative, antimicrobial, and enzyme inhibition activities for 18 apple and 18 grape juices from markets in Serbia and Germany. Bioactive zones of interest were eluted using an elution head-based interface and further characterized by electrospray ionization high-resolution mass spectrometry. The different profiles were evaluated chemometrically, and several compounds, which were characteristic of samples from different markets located in Serbia and Germany, were identified in apple juice (such as chlorogenic acid, phloridzin, epicatechin, and caffeic acid) and grape juice (such as chlorogenic acid, epicatechin, and quercetin). The developed rapid and simple method for the quality assessment of fruit juices coming from different (geographic) markets showed clear quality differences. Thus, it could be used to learn more about quality differences, to detect fraud in fruit juice production, and to verify the authenticity of the origin.


Assuntos
Catequina , Malus , Vitis , Acetilcolinesterase , Butirilcolinesterase , Quimiometria , Ácido Clorogênico , Cromatografia em Camada Fina , Sucos de Frutas e Vegetais , Sérvia
11.
Food Chem ; 378: 132113, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35033722

RESUMO

The study aimed to analyze trace elements content in baby purees and fruit juices and to evaluate the health risk of young children. The average daily dose, hazard quotient, hazard index and total diet hazard quotient were calculated to assess the potential health risk on per capita and consumers only groups of infants and toddlers. There was no significant health risk for studied groups regarding the intake of trace elements via purees and juices consumption. Health risk for lead was not estimated since the oral reference dose for this metal was not yet established and PTWI value was withdrawn. The average daily dose of lead for infants (0.32 - 0.46 µg/kg bw/day) and toddlers (2.01 - 2.29 µg/kg bw/day) were in accordance with the daily lead exposure intervals estimated by EFSA. Applying statistical analysis, the products were classified into three groups according to the content of trace elements.


Assuntos
Oligoelementos , Pré-Escolar , Dieta , Sucos de Frutas e Vegetais , Humanos , Lactente , Medição de Risco
12.
Food Chem ; 373(Pt A): 131424, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34710685

RESUMO

The aim of this work was to develop an approach combining LC-MS-based metabolomics and machine learning to distinguish between and predict authentic and adulterated lemon juices. A targeted screening of six major flavonoids was first conducted using ultraviolet ion trap MS. To improve the prediction accuracy, an untargeted methodology was carried out using UHPLC-QTOF/MS. Based on the acquired metabolic profiles, both PCA and PLS-DA were conducted. Results exhibited a cluster pattern and a separation potential between authentic and adulterated samples. Five machine learning models were then developed to further analyze the data. The model of support vector machine achieved the highest prediction power, with accuracy up to 96.7 ± 7.5% for the cross-validation set and 100% for the testing set. In addition, 79 characteristic m/z were tentatively identified. This work demonstrated that untargeted screening coupled with machine learning models can be a powerful tool to facilitate detection of lemon juice adulteration.


Assuntos
Sucos de Frutas e Vegetais , Metabolômica , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Aprendizado de Máquina , Espectrometria de Massas
13.
Molecules ; 26(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34946505

RESUMO

The study's purpose was to find and create a nourishing fruit juice made from avocado to suit nutritional and health demands. In this regard, the avocado juice was formulated using a statistical technique, and its biochemical and phytochemical characteristics were evaluated. Statistically formulated fruit juice was evaluated for its sensory characteristics, proximate composition, nutrients and vitamins, total phenols and flavonoids, and for its antioxidant ability, in addition to a shelf-life test. The optimal amount of all ingredients included in the mathematical model for the preparation of the juice was 150 g of Persea americana (Avocado) fruit pulp, 12.5 g of honey and 100 mL of water. In fact, the composition of avocado juice was found to have higher phenolic (910.36 ± 0.215 mg EAG g-1/mL) and flavonoid (56.32 ± 1.26 mg QE g-1/ mL) amounts. DPPH, ABTS and FRAP antioxidant assays tended to be high compared with a standard. The shelf-life analysis indicated that the processed avocado juice (V7) had a long shelf life. In view of all these merits, a statistically formulated recipe for avocado fruit juice was recommended for the formulation of the most preferred health drink.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Sucos de Frutas e Vegetais/análise , Persea/química , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Composição de Medicamentos , Flavonoides/química , Flavonoides/isolamento & purificação , Recuperação de Fluorescência Após Fotodegradação , Humanos , Fenóis/química , Fenóis/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores
14.
Int J Mol Sci ; 22(19)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34639147

RESUMO

In this work, we verified the possibility of valorizing a major waste product of the potato starch industry, potato tuber juice (PJ). We obtained a cost-effective, ecological-friendly microbiological medium that yielded bacterial cellulose (BC) with properties equivalent to those from conventional commercial Hestrin-Schramm medium. The BC yield from the PJ medium (>4 g/L) was comparable, despite the lack of any pre-treatment. Likewise, the macro- and microstructure, physicochemical parameters, and chemical composition showed no significant differences between PJ and control BC. Importantly, the BC obtained from PJ was not cytotoxic against fibroblast cell line L929 in vitro and did not contain any hard-to-remove impurities. The PJ-BC soaked with antiseptic exerted a similar antimicrobial effect against Staphylococcus aureus and Pseudomonas aeruginosa as to BC obtained in the conventional medium and supplemented with antiseptic. These are very important aspects from an application standpoint, particularly in biomedicine. Therefore, we conclude that using PJ for BC biosynthesis is a path toward significant valorization of an environmentally problematic waste product of the starch industry, but also toward a significant drop in BC production costs, enabling wider application of this biopolymer in biomedicine.


Assuntos
Bactérias/metabolismo , Celulose/biossíntese , Análise Custo-Benefício , Fibroblastos/metabolismo , Resíduos Industriais/economia , Solanum tuberosum/química , Animais , Celulose/economia , Meios de Cultura , Sucos de Frutas e Vegetais/análise , Camundongos , Amido/química
15.
Nutrients ; 13(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34444928

RESUMO

Given the importance of exercise economy to endurance performance, we implemented two strategies purported to reduce the oxygen cost of exercise within a 4 week training camp in 21 elite male race walkers. Fourteen athletes undertook a crossover investigation with beetroot juice (BRJ) or placebo (PLA) [2 d preload, 2 h pre-exercise + 35 min during exercise] during a 26 km race walking at speeds simulating competitive events. Separately, 19 athletes undertook a parallel group investigation of a multi-pronged strategy (MAX; n = 9) involving chronic (2 w high carbohydrate [CHO] diet + gut training) and acute (CHO loading + 90 g/h CHO during exercise) strategies to promote endogenous and exogenous CHO availability, compared with strategies reflecting lower ranges of current guidelines (CON; n = 10). There were no differences between BRJ and PLA trials for rates of CHO (p = 0.203) or fat (p = 0.818) oxidation or oxygen consumption (p = 0.090). Compared with CON, MAX was associated with higher rates of CHO oxidation during exercise, with increased exogenous CHO use (CON; peak = ~0.45 g/min; MAX: peak = ~1.45 g/min, p < 0.001). High rates of exogenous CHO use were achieved prior to gut training, without further improvement, suggesting that elite athletes already optimise intestinal CHO absorption via habitual practices. No differences in exercise economy were detected despite small differences in substrate use. Future studies should investigate the impact of these strategies on sub-elite athletes' economy as well as the performance effects in elite groups.


Assuntos
Beta vulgaris , Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Sucos de Frutas e Vegetais , Caminhada/fisiologia , Adulto , Atletas , Humanos , Masculino , Oxirredução , Consumo de Oxigênio
16.
Appetite ; 163: 105232, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33811945

RESUMO

Persons look for beverages to satisfy thirst (refresh) and feel fulfilled (thick). However, refreshing and thickness are concepts that lack a measurement instrument that captures an accurate judgment of consumers' perceptions. This research aims to propose a tool to assess consumers' refreshing and thickness expectations of fruit juices. Items were developed through a two-stage qualitative-exploratory study, followed by a quantitative study describing the scale's composition using an Item Response Theory approach. Hence, we suggest a set of items to consider when measuring both concepts from a perception task. Moreover, results show that thickness and refreshing are distinct and independent ideas. We provide a theoretical contribution defining each construct and recognizing the attributes that best describe refreshing and thickness for five different fruit juices. Our methodological contribution is creating a scale for each of the concepts. Practically, developing a thickness and refreshing scale is useful for product developers and marketers who expect to satisfy consumers' needs for soft drinks.


Assuntos
Bebidas , Sucos de Frutas e Vegetais , Bebidas/análise , Bebidas Gaseificadas , Frutas , Psicometria , Sede
17.
Food Res Int ; 140: 110085, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648303

RESUMO

Ultraviolet-C (UV-C) light is a non-thermal method for improving the safety and shelf-life of cold-pressed juices with minimal impact on quality and nutrition. Most previous studies have investigated fruit juices as opposed to particulate dense leafy green juices with very low UV transmittance (UVT). Pure kale juice is a common juice ingredient and represents the worst-case scenario in terms of low UVT green juices. This study validated the use of continuous benchtop UV-C treatment at 253.7 nm for 5-log reduction of non-pathogenic Escherichia coli P36 in kale juice. An average absorbed fluence of 108.3 mJ cm-2 resulted in a 5.8 log reduction of E. coli P36. At a fluence comparable to that reported for commercial juice processing (74.0 mJ cm-2), kale juice exhibited a decrease in absorption coefficient, while sedimentation, supernatant browning and pectin methylesterase activity increased with no effect on the chlorophyll content, colour, viscosity or antioxidant content.


Assuntos
Brassica , Escherichia coli , Microbiologia de Alimentos , Sucos de Frutas e Vegetais , Raios Ultravioleta
18.
Int J Food Microbiol ; 338: 109006, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33302194

RESUMO

Alicyclobacillus spp. has recently received much attention due to its implication in the spoilage of pasteurized fruit juices, which is characterized by the formation of guaiacol. Previous researches indicate that not all Alicyclobacillus spp. are able to produce guaiacol. The aim of this study was to identify possible differences in the vanillic acid decarboxylase gene involved in guaiacol biosynthesis and then develop specific detection methods for guaiacol producing Alicyclobacillus. Agarose gel electrophoresis results showed that the partial vdcC gene was present in all the guaiacol producing Alicyclobacillus, but absent in non-guaicaol producing strains apart from A. fastidiosus DSM 17978. On the basis of the vdcC gene sequence, a primer pair specific to A. acidoterrestris was designed; then a SYBR Green I real time PCR was established for the direct quantification of A. acidoterrestris in apple juice, and the detection limit was 2.6 × 101 CFU/mL. The developed real time PCR system was used to detect A. acidoterrestris in 36 artificially contaminated apple juice samples and guaiacol production in the sample was also analyzed by GC-MS. The Gompertz model was employed to describe the relationship between A. acidoterrestris cell concentration and guaiacol content, and the value of R2 was 0.854. This work provides an alternative to conventional methods of guaiacol quantification and A. acidoterrestris detection and could be very useful for the early recognition of A. acidoterrestris contamination in fruit juices.


Assuntos
Alicyclobacillus/genética , Carboxiliases/genética , Microbiologia de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Guaiacol/análise , Reação em Cadeia da Polimerase em Tempo Real , Alicyclobacillus/enzimologia , Cromatografia Gasosa-Espectrometria de Massas , Malus/microbiologia
19.
J Food Prot ; 84(3): 497-508, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33064148

RESUMO

ABSTRACT: The scope of the present study was to assess the spoilage potential of different Alicyclobacillus spp. in commercial pasteurized (ambient-stable) plant-based dairy beverages mixed with fruit juices at different inoculation levels and storage temperatures. Different products (coconut and berry [CB]; almond, mango, and passionfruit [AMP]; and oat, strawberry, and banana [OSB]) were inoculated with 10 or 2 × 103 spores per mL of either Alicyclobacillus acidoterrestris, Alicyclobacillus fastidiosus, or Alicyclobacillus acidocaldarius strain composites, whereas noninoculated samples served as controls. Samples inoculated with A. acidoterrestris and A. fastidiosus were stored at 30 and 45°C, whereas A. acidocaldarius storage took place at 50°C for 240 days. Gas composition, Alicyclobacillus spp. populations, total viable counts, pH, water activity, color, and guaiacol off-taste were monitored. CB and AMP supported growth of A. acidoterrestris and A. fastidiosus, reaching populations of 4.0 to 5.0 log CFU/mL. In OSB, populations of A. fastidiosus remained close to the initial inoculation levels during storage at 30°C, whereas at 45°C, the populations declined <1 CFU/mL. A. acidocaldarius growth was supported in CB samples, but not in AMP and OSB samples, reaching ca. 3.0 log CFU/mL at 50°C, regardless of initial inoculum size. Total color change was increased during storage; however, the instrumentally recorded color changes were not macroscopically visible. Spoilage in terms of guaiacol off-taste was identified only in CB and AMP samples inoculated with A. acidoterrestris after 60 days at 30 and 45°C. The increased popularity of these products along with the scarcity of existing literature related to their spoilage by Alicyclobacillus spp., render the contribution of the findings and data of present study critical for assessing the significance of Alicyclobacillus spp. as a potential spoilage hazard in these products and for assisting in the design and implementation of effective mitigation strategies by the beverage industry.


Assuntos
Alicyclobacillus , Bebidas , Microbiologia de Alimentos , Frutas , Sucos de Frutas e Vegetais , Esporos Bacterianos
20.
Nutrients ; 12(9)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878096

RESUMO

It is well known that reducing consumption of sugar is a global public health priority. Beverages were the primary source of total sugar intake from processed foods. However, there are few studies investigating the trend of beverage consumption among children and adolescents in Korea. We examined the overall trend in beverage consumption among 11,996 participants aged 10-18 years who were enrolled in the Korea National Health and Nutrition Examination Survey (KNHANES) (1998-2018). Further, we examined the effect of beverage types on beverage consumption-related demographic factors and obesity among 6121 participants using the recent 24 h dietary recall data (2010-2018) that captured the consumption of fruit and vegetable juices, soft drinks, milk and milk-based products and alcoholic beverages. Demographic characteristics, including sex, age, body mass index, household income level and residential area, were considered. Consumers' overall beverage intake and the percentage of energy derived from fruit and vegetable juices and soft drinks steadily increased from 1998 to 2016-2018 (p-trend < 0.0001); in contrast, dairy product consumption declined since 2010-2012. The main sources of beverage-based calories were fruit and vegetable juices (107.5 kcal/day), soft drinks (145.2 kcal/day), dairy products (181.8 kcal/day) and alcoholic beverages (103.5 kcal/day). Also, Korean adolescents aged 16-18 years consumed more soft drinks, fewer dairy products and higher alcoholic drinks than other age groups; particularly, boys consumed more energy from beverages (p < 0.0001). The odds ratios of obesity prevalence tended to be higher for soft drink consumption than for other beverages but this was not significant. The consumption of fruit and vegetable juices and milk and milk products showed a marginal association with a reduced risk of obesity prevalence. Since beverage consumption has increased steadily among Korean children and adolescents, appropriate interventions are needed. In the future, data from a larger sample of Korean children and adolescents are necessary to identify significant differences and longitudinal studies are necessary to examine the causalities.


Assuntos
Bebidas , Demografia , Dieta , Obesidade Infantil/epidemiologia , Fatores Socioeconômicos , Adolescente , Bebidas Alcoólicas , Animais , Estatura , Índice de Massa Corporal , Peso Corporal , Bebidas Gaseificadas , Criança , Estudos Transversais , Registros de Dieta , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/análise , Feminino , Sucos de Frutas e Vegetais , Humanos , Masculino , Rememoração Mental , Leite , Inquéritos Nutricionais , Prevalência , Recomendações Nutricionais , República da Coreia/epidemiologia
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