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1.
Int J Mol Sci ; 24(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37569836

RESUMO

The Food and Drug Administration has recently classified the IQOS electronic cigarette as a modified-risk tobacco product. However, IQOS cigarettes still release various harmful constituents typical of conventional cigarettes (CCs), although the concentrations are markedly lower. Here, we investigated the damaging effects of IQOS smoking on the liver. Male Sprague Dawley rats were exposed, whole body, 5 days/week for 4 weeks to IQOS smoke (4 sticks/day), and hepatic xenobiotic metabolism, redox homeostasis and lipidomic profile were investigated. IQOS boosted reactive radicals and generated oxidative stress. Exposure decreased cellular reserves of total glutathione (GSH) but not GSH-dependent antioxidant enzymes. Catalase and xanthine oxidase were greater in the exposed group, as were various hepatic CYP-dependent monooxygenases (CYP2B1/2, CYP1A1, CYP2A1, CYP2E1-linked). Respiratory chain activity was unaltered, while the number of liver mitochondria was increased. IQOS exposure had an impact on the hepatic lipid profile. With regard to the expression of some MAP kinases commonly activated by CC smoking, IQOS increased the p-p38/p38 ratio, while erythroid nuclear transcription factor 2 (Nrf2) was negatively affected. Our data suggest that IQOS significantly impairs liver function, supporting the precautionary stance taken by the WHO toward the use of these devices, especially by young people and pregnant women.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Gravidez , Ratos , Animais , Masculino , Feminino , Humanos , Fumaça , Ratos Sprague-Dawley , Produtos do Tabaco/efeitos adversos , Fígado
2.
Antioxidants (Basel) ; 11(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35739954

RESUMO

The use of natural plant extracts with standardised antioxidant properties is a growing strategy to stabilise food products. The use of a rosemary lipophilic extract (RLE), obtained from the by-product of high-yield selected plants and rich in polyphenols (334 mg/g, with diterpenes such as carnosic acid and carnosol as main compounds), is here proposed. Four RLE doses (0, 0.21, 0.42 and 0.63 g/kg) were tested in a salmon pâté formulated with sunflower oil and linseed, which was pasteurised (70 °C for 30 min) and subjected to storage at 4 °C and 600 lux for 42 days. Rosemary diterpenes resisted pasteurisation without degrading and showed antioxidant activities during the shelf-life of pasteurised pâté. RLE addition led to increased peroxide value (from 3.9 to 5.4 meq O2/kg), but inhibited formation of secondary oxidised lipids such as malondialdehyde (from 1.55 to 0.89 mg/g) and cholesterol oxidation products (from 286 to 102 µg/100 g) and avoided discolouration (slight brownness) in the refrigerated pâté. However, this did not entail relevant changes in fatty acid content or in the abundance of volatile organic compounds from oxidised lipids. Increasing the RLE dose only improved its antioxidant efficacy for some oxidation indexes. Thus, the oxidative deterioration of these types of fish emulsion can be naturally controlled with rosemary extracts rich in diterpenes.

3.
Antioxidants (Basel) ; 12(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36670884

RESUMO

The aim of this study was to assess the impact of in vitro digestion on the antioxidant activity of three extracts rich in phenols (two purified organic extracts (A20, A21) and one powdered extract stabilized with maltodextrins (SP)) obtained from olive mill wastewaters (OMWW). The content and composition of phenols and antioxidant activity was determined before and after in vitro digestion. The phenol content of the A20 and A21 samples were higher (>75%) than that of the SP sample before in vitro digestion. After the entire in vitro digestion, 89.3, 76.9, and 50% loss of phenols was found in A20, A21 and SP, respectively. ABTS•+ and ORAC values decreased during in vitro digestion of A20 and A21 samples, while they remained almost constant in SP. IC50 increased during digestion of A20 and A21, evidencing a loss of antioxidant capacity after the intestinal phase; an opposite IC50 trend was noted in SP, confirming the protective role of maltodextrins. For these reasons, SP represents a promising formulation to be used in the food field.

4.
Nicotine Tob Res ; 23(12): 2127-2134, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34036368

RESUMO

INTRODUCTION: Recently, the Food and Drug Administration authorized the marketing of IQOS Tobacco Heating System as a Modified Risk Tobacco Product based on an electronic heat-not-burn technology that purports to reduce the risk. METHODS: Sprague-Dawley rats were exposed in a whole-body mode to IQOS aerosol for 4 weeks. We performed the chemical characterization of IQOS mainstream and we studied the ultrastructural changes in trachea and lung parenchyma of rats exposed to IQOS stick mainstream and tissue pro-inflammatory markers. We investigated the reactive oxygen species amount along with the markers of tissue and DNA oxidative damage. Moreover, we tested the putative genotoxicity of IQOS mainstream through Ames and alkaline Comet mutagenicity assays. RESULTS: Here, we identified irritating and carcinogenic compounds including aldehydes and polycyclic aromatic hydrocarbons in the IQOS mainstream as sign of incomplete combustion and degradation of tobacco, that lead to severe remodelling of smaller and largest rat airways. We demonstrated that IQOS mainstream induces lung enzymes that activate carcinogens, increases tissue reactive radical concentration; promotes oxidative DNA breaks and gene level DNA damage; and stimulates mitogen activated protein kinase pathway which is involved in the conventional tobacco smoke-induced cancer progression. CONCLUSIONS: Collectively, our findings reveal that IQOS causes grave lung damage and promotes factors that increase cancer risk. IMPLICATIONS: IQOS has been proposed as a safer alternative to conventional cigarettes, due to depressed concentration of various harmful constituents typical of traditional tobacco smoke. However, its lower health risks to consumers have yet to be determined. Our findings confirm that IQOS mainstream contains pyrolysis and thermogenic degradation by-products, the same harmful constituents of traditional cigarette smoke, and, for the first time, we show that it causes grave lung damage and promotes factors that increase cancer risk in the animal model.


Assuntos
Fumaça , Produtos do Tabaco , Animais , DNA , Pulmão , Ratos , Ratos Sprague-Dawley , Fumar , Nicotiana , Produtos do Tabaco/toxicidade
5.
Regul Toxicol Pharmacol ; 109: 104500, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629780

RESUMO

Electronic cigarette (e-cigarette; e-cig) use has grown exponentially in recent years despite their unknown health effects. E-cig aerosols are now known to contain hazardous chemical compounds, including carbonyls and reactive oxygen species (ROS), and these compounds are directly inhaled by consumers during e-cig use. Both carbonyls and ROS are formed when the liquid comes into contact with a heating element that is housed within an e-cig's atomizer. In the present study, the effect of coil resistance (1.5â€¯Ω and 0.25â€¯Ω coils, to obtain a total wattage of 8 ±â€¯2 W and 40 ±â€¯5 W, respectively) on the generation of carbonyls (formaldehyde, acetaldehyde, acrolein) and ROS was investigated. The effect of the aerosols generated by different coils on the viability of H1299 human lung carcinoma cells was also evaluated. Our results show a significant (p < 0.05) correlation between the low resistance coils and the generation of higher concentrations of the selected carbonyls and ROS in e-cig aerosols. Moreover, exposure to e-cig vapor reduced the viability of H1299 cells by up to 45.8%, and this effect was inversely related to coil resistance. Although further studies are needed to better elucidate the potential toxicity of e-cig emissions, our results suggest that these devices may expose users to hazardous compounds which, in turn, may promote chronic respiratory diseases.


Assuntos
Aerossóis/toxicidade , Sistemas Eletrônicos de Liberação de Nicotina , Exposição por Inalação/efeitos adversos , Doenças Respiratórias/prevenção & controle , Vaping/efeitos adversos , Acetaldeído/química , Acetaldeído/toxicidade , Acroleína/química , Acroleína/toxicidade , Aerossóis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doença Crônica/prevenção & controle , Eletricidade , Formaldeído/química , Formaldeído/toxicidade , Calefação/efeitos adversos , Humanos , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/toxicidade , Doenças Respiratórias/induzido quimicamente , Testes de Toxicidade Crônica/métodos
6.
Toxicol Sci ; 172(1): 132-145, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31388676

RESUMO

Despite the knowledge gap regarding the risk-benefit ratio of the electronic cigarette (e-cig), its use has grown exponentially, even in teenagers. E-cig vapor contains carcinogenic compounds (eg, formaldehyde, acetaldehyde, and acrolein) and free radicals, especially reactive oxygen species (ROS) that cause toxicological effects, including DNA damage. The role of e-cig voltage customization on molecule generation has been reported, but the effects of the resistance on e-cig emissions and toxicity are unknown. Here, we show that the manipulation of e-cig resistance influences the carbonyls production from nonnicotine vapor and the oxidative and inflammatory status in a rat model. Fixing the voltage at the conventional 3.5 V, we observed that the amount of the selected aldehydes increased as the resistance decreased from 1.5 to 0.25 Ω. Under these conditions, we exposed Sprague Dawley rats to e-cig aerosol for 28 days, and we studied the pulmonary inflammation, oxidative stress, tissue damage, and blood homeostasis. We found a perturbation of the antioxidant and phase II enzymes, probably related to the increased ROS levels due to the enhanced xanthine oxidase and P450-linked monooxygenases. Furthermore, frames from scanning electron microscope showed a disorganization of alveolar and bronchial epithelium in 0.25 Ω group. Overall, various toxicological outcomes, widely recognized as smoke-related injuries, can potentially occur in e-cig consumers who use low-voltage and resistance device. Our study suggests that certain "tips for vaping safety" cannot be established, and encourages further independent investigations to help public health agencies in regulating the e-cig use.

7.
J Steroid Biochem Mol Biol ; 193: 105430, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31325497

RESUMO

Over the past few years, the contribution of oxysterols to the onset and development of some of the major neurodegenerative diseases (such as Alzheimer's and Parkinson's diseases) has been scientifically asserted, being mainly related to altered brain cholesterol homeostasis. To counteract oxysterol induced inflammation at neuronal level, one possible intervention approach is the administration of some nutrients and/or plant secondary metabolites. On the other hand, the pleiotropic beneficial effects of physical activity seem to play an important role on prevention and counteraction of neurodegenerative diseases, through the modulation of oxysterol homeostasis and the prevention of demyelination. The present review provides a picture of the promising role of nutraceuticals and physical activity on oxysterol-mediated neurodegeneration, pointing out also the different in vitro and in vivo aspects that need to be further investigated for a better understanding of the association of these three counterparts and their overall effect on people at increased risk for neurodegenerative diseases.


Assuntos
Suplementos Nutricionais , Exercício Físico , Doenças Neurodegenerativas/metabolismo , Oxisteróis/metabolismo , Animais , Humanos , Doenças Neurodegenerativas/prevenção & controle
8.
Life Sci ; 228: 53-65, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31029780

RESUMO

Despite the lack of knowledge of the effects of electronic cigarettes (e-cigarettes, e-cigs) on public health, they have been proposed as a part of smoking cessation efforts. Recently, several basic scientific studies have pointed out how e-cigs can generate carcinogens, such as e-cig liquid thermal degradation by-products, and how the exposure can lead to genomic damage through inhibiting DNA repair or disrupting the redox homeostasis. However, scientific studies have pointed out how e-cigs can generate carcinogens and their release could be avoided setting the device to a low-voltage regimen. To test this feasibility, we show the effects of e-cig vapour generated from a low-voltage device filled with a nicotine-free liquid on rat testicular functions. The chemical analysis revealed the presence of carbonyls, such as formaldehyde, acetaldehyde and acrolein. Rats exposed reported a lower relative testis weight and higher levels of lactate dehydrogenase (LDH) as tissue damage marker, along with an impairment of 3ß-hydroxysteroid dehydrogenase (3ß-HSD), 17ß-hydroxysteroid dehydrogenase (17ß-HSD) and glucose-6-phosphate dehydrogenase (G6PDH) as key enzymes in the steroidogenesis pathway. The pro-oxidative environment was confirmed by the higher amount of reactive oxygen species (ROS), the development of lipid peroxidation and protein carbonylation, as well as from the disruption of antioxidant capability. Finally, we observed a higher rate of DNA unwinding in white blood cell line and boosted lipoxygenase (LOX)-linked activity, a tumour promotion marker. Even with the device setting at weak conditions, our results if extrapolated to humans suggest that exposure to e-cig vapours might alter gonads function in male vapers.


Assuntos
Quebras de DNA , Sistemas Eletrônicos de Liberação de Nicotina/métodos , Estresse Oxidativo , Testículo/enzimologia , Testículo/fisiopatologia , Acetaldeído/análise , Acetaldeído/metabolismo , Acroleína/análise , Acroleína/metabolismo , Animais , Quebras de DNA/efeitos dos fármacos , Eletricidade , Formaldeído/análise , Formaldeído/metabolismo , Masculino , Tamanho do Órgão , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Abandono do Hábito de Fumar , Testículo/efeitos dos fármacos , Testículo/metabolismo , Volatilização
9.
J Food Drug Anal ; 26(4): 1283-1292, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30249327

RESUMO

A routine method for determining cannabinoids in Cannabis sativa L. inflorescence, based on Fast gas chromatography coupled to mass spectrometry (Fast GC/MS), was developed and validated. To avoid the decarboxylation of carboxyl group of cannabinoids, different derivatization approaches, i.e. silylation and esterification (diazomethane-mediated), reagents and solvents (pyridine or ethyl acetate), were tested. The methylation significantly increased the signal-to-noise ratio of all carboxylic cannabinoids, except for cannabigerolic acid (CBGA). Since diazomethane is not commercially available, is considered a hazardous reactive and requires 1-day synthesis by specialized chemical staff, silylation was used along the whole validation of a routine method. The method gave a fast (total analysis time < 7.0 min) and satisfactory resolution (R > 1.1), with a good repeatability (intraday < 8.38%; interday < 11.10%) and sensitivity (LOD < 11.20 ng/mL). The Fast GC/MS method suitability for detection of cannabinoids in hemp inflorescences, was tested; a good repeatability (intraday < 9.80%; interday < 8.63%), sensitivity (LOD < 58.89 ng/mg) and robustness (<9.52%) was also obtained. In the analyzed samples, the main cannabinoid was cannabidiolic acid (CBDA, 5.19 ± 0.58 g/100 g), followed by cannabidiol (CBD, 1.56 ± 0.03 g/100 g) and CBGA (0.83 g/100 g). Δ9-tetrahydrocannabivarine (THCV) was present at trace level. Therefore, the developed routine Fast GC/MS method could be a valid alternative for a fast, robust and high sensitive determination of main cannabinoids present in hemp inflorescences.


Assuntos
Canabinoides/química , Cannabis/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Estrutura Molecular , Sensibilidade e Especificidade
10.
Biochimie ; 153: 99-108, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30077815

RESUMO

The electronic cigarettes (e-cigarettes, e-cigs) have become the most sought-after alternative to the traditional cigarettes, partly due to the widespread perception of safety. However, the high temperature reached by e-cig solutions can generate toxic compounds, some of which are listed as known human carcinogens. To evaluate the impact of e-cig aerosol on rat brain lipid profile, twenty male Sprague Dawley rats were exposed to 11 cycles/day (E-cig group), to consume 1 mL/day of e-liquid, for 5 days/week up to 8 weeks. Ten rats were sacrificed after 4 weeks (4w) and ten at the end of treatment (8w). The composition of total fatty acids, sterols and oxysterols of the lipid fraction of rat brains, was analyzed. The results of the E-cig group were compared with those of the control group (not exposed). After 8 weeks, the saturated fatty acids significantly raised up to 7.35 mg/g tissue, whereas polyunsaturated fatty acids decreased reaching 3.17 mg/g. The e-cig vaping increased both palmitic (3.43 mg/g) and stearic acids (3.82 mg/g), while a significant decrement of arachidonic (1.32 mg/g) and docosahexaenoic acids (1.00 mg/g) was found. Atherogenic (0.5) and thrombogenic (1.12) indices also increased in 8w treated animals. The e-cig aerosol significantly impacted the cholesterol homeostasis, since the latter at 8w (21.57 mg/g) was significantly lower than control (24.56 mg/g); moreover, a significant increase of 7-dehydrocholesterol (1.87 mg/g) was also denoted in e-cig group. The e-cig aerosol also reduced the oxysterol formation (19.55 µg/g) after 4 weeks of exposure, except for triol and 5α,6α-epoxycholesterol (α-EC). The principal component analysis (PCA) separated all E-cig from control groups, evidencing that oxysterols (except triol and 24(S)-hydroxycholesterol (24(S)-HC)) were inversely correlated to 7-DHC and TI. The present research revealed that e-cigs aerosol affected the lipid and cholesterol homeostasis in rat brain, which could contribute to the new occurrence of some neurodegenerative diseases.


Assuntos
Aerossóis/toxicidade , Encéfalo/efeitos dos fármacos , Sistemas Eletrônicos de Liberação de Nicotina , Metabolismo dos Lipídeos/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Homeostase , Masculino , Oxisteróis/metabolismo , Análise de Componente Principal , Ratos Sprague-Dawley
11.
Sci Rep ; 7(1): 2028, 2017 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-28515485

RESUMO

Electronic cigarettes (e-cigs) are devices designed to deliver nicotine in a vaping solution rather than smoke and without tobacco combustion. Perceived as a safer alternative to conventional cigarettes, e-cigs are aggressively marketed as lifestyle-choice consumables, thanks to few restrictions and a lack of regulatory guidelines. E-cigs have also gained popularity among never-smokers and teenagers, becoming an emergent public health issue. Despite the burgeoning worldwide consumption of e-cigs, their safety remains largely unproven and it is unknown whether these devices cause in vivo toxicological effects that could contribute to cancer. Here we demonstrate the co-mutagenic and cancer-initiating effects of e-cig vapour in a rat lung model. We found that e-cigs have a powerful booster effect on phase-I carcinogen-bioactivating enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), and increase oxygen free radical production and DNA oxidation to 8-hydroxy-2'-deoxyguanosine. Furthermore, we found that e-cigs damage DNA not only at chromosomal level in peripheral blood, such as strand breaks in leucocytes and micronuclei formation in reticulocytes, but also at gene level such as point mutations in urine. Our results demonstrate that exposure to e-cigs could endanger human health, particularly among younger more vulnerable consumers.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Neoplasias/etiologia , Neoplasias/metabolismo , Animais , Antioxidantes/metabolismo , Dano ao DNA , Cromatografia Gasosa-Espectrometria de Massas , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Neoplasias/patologia , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo , Medição de Risco , Fatores de Risco , Compostos Orgânicos Voláteis/efeitos adversos , Compostos Orgânicos Voláteis/análise
12.
J Food Sci ; 81(5): H1320-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27095513

RESUMO

Dietary components in combination may act synergistically and produce enhanced biological activities. Herein, we investigated the anti-inflammatory effects of 2 flavonoids, that is luteolin (LUT) and tangeretin (TAN) in combination. Lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages were treated with noncytotoxic concentrations of LUT, TAN, and their combinations. The results showed that LUT/TAN in combination produced synergistic inhibitory effects on LPS-stimulated production of nitric oxide (NO). ELISA results demonstrated that LUT/TAN in combination caused stronger suppression on the LPS-induced overexpression of proinflammatory mediators, such as prostaglandin E2 (PGE2 ), interleukin (IL)-1ß, and IL-6 than LUT or TAN alone. Immunoblotting and Real-Time PCR analyses showed that LUT/TAN combination significantly decreased LPS-induced protein and mRNA expression of inducible nitric oxide synthase and cyclooxygenase-2. These inhibitory effects of the combination treatment were stronger than those produced by LUT or TAN alone. Overall, our results demonstrated for the first time that combination of LUT and TAN produced synergistic anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonas/farmacologia , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/biossíntese , Sinergismo Farmacológico , Flavonas/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Luteolina/farmacologia , Luteolina/uso terapêutico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/uso terapêutico , Células RAW 264.7 , RNA Mensageiro/metabolismo
13.
Food Chem ; 182: 95-104, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25842314

RESUMO

The effect of eleven compounds extracted from red propolis on the oxidative stability of a functional emulsion was evaluated. Emulsions prepared with Echium oil as omega 3 (ω-3 FA) source, containing 1.63 g/100mL of α-linolenic acid (ALA), 0.73 g/100 mL of stearidonic acid (SDA) and 0.65 g/100mL of plant sterol esters (PSE) were prepared without or with phenolic compounds (vanillic acid, caffeic acid, trans-cinnamic acid, 2,4-dihydroxycinnamic acid, p-coumaric acid, quercetin, trans-ferulic acid, trans,trans-farnesol, rutin, gallic acid or sinapic acid). tert-Butylhydroquinone and a mixture containing ascorbic acid and FeSO4 were applied as negative and positive controls of the oxidation. Hydroperoxide, thiobarbituric acid reactive substances (TBARS), malondialdehyde and phytosterol oxidation products (POPs) were evaluated as oxidative markers. Based on hydroperoxide and TBARS analysis, sinapic acid and rutin (200 ppm) showed the same antioxidant activity than TBHQ, representing a potential alternative as natural antioxidant to be applied in a functional emulsion containing ω-3 FA and PSE.


Assuntos
Ácido Ascórbico/química , Ácidos Graxos Ômega-3/química , Fenóis/química , Fitosteróis/química , Antioxidantes/análise , Ácido Gálico
14.
J Sci Food Agric ; 95(8): 1736-46, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25156388

RESUMO

BACKGROUND: The effect of innovative multilayer packaging materials versus a standard one on biscuit quality was studied during accelerated storage at 25, 35, 45 °C and 50% relative humidity for 92 days. Three different packaging materials were used: metalized orientated polypropylene (OPP)/paper (control); metalized poly-lactic acid (PLA)/paper; metalized OPP with ethylene vinyl acetate pro-oxidant additive (EVA-POA)/paper. EVA-POA additive is used to make the plastic layer biodegradable. Various quality sample parameters (moisture, water activity (aw ), texture, peroxide value (PV), hexanal) were analysed during storage. Rate constants (k) and activation energies (Ea ) of hydration reactions and hexanal formation were calculated. RESULTS: No remarkable differences in the evolution of primary and secondary lipid oxidation were observed among differently packed biscuits during storage. All samples maintained PV levels between 4 and 14 meq O2 kg(-1) oil. The product in flexible packaging with PLA reached the highest moisture and aw levels, but they did not significantly and adversely affect the other quality characteristics. CONCLUSION: The obtained results demonstrate that the new tested packaging materials were suitable for commercial biscuit storage, having similar performance and preservation effects on the overall product quality to those of the standard one. Furthermore, these results could make a contribution to the food industry, encouraging the use of packaging materials with a negligible environmental impact as an alternative to petroleum-based ones.


Assuntos
Embalagem de Alimentos/instrumentação , Conservação de Alimentos/métodos , Qualidade dos Alimentos , Etilenos , Umidade , Ácido Láctico , Peroxidação de Lipídeos , Metais , Papel , Poliésteres , Polímeros , Polipropilenos , Polivinil , Compostos de Vinila , Água/análise
15.
Food Chem ; 166: 346-351, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053066

RESUMO

This study evaluates the oxidation level of high-oleic sunflower oil (HOSO) plated onto porous starch as an alternative to spray drying. Encapsulated oils were subjected to accelerated oxidation by heat and light exposure, and peroxide value (PV) and conjugated dienes (CD) were measured. Bulk oil was the control. PV increased in all samples with increased light exposure, with similar values being reached by oil carried on porous starch and spray dried oil. The encapsulation processes determined a reduced effect of light on the increase of CD in the oil, as compared to bulk oil. Spray dried oil presented the highest CD in the experimental domain considered. Since similar levels of PV and lower levels of CD were shown in the HOSO carried on porous starch compared to the spray dried HOSO, plating flavour oils on porous starch could be a suitable technological alternative to spray drying, for flavour encapsulation.


Assuntos
Ácido Oleico/química , Óleos de Plantas/química , Amido/química , Oxirredução , Óleo de Girassol
16.
J Agric Food Chem ; 62(44): 10836-44, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25321090

RESUMO

The reuse of coffee silverskin (CS), the main waste product of the coffee-roasting industry, could be an alternative to its environmental disposal. However, CS could also contain undesirable compounds, such as ochratoxin A (OTA) and phytosterol oxidation products (POPs). A study on the composition of CS (caffeine, moisture, dietary fibers, carbohydrates, and polyphenol contents) was carried out, with emphasis on OTA and POPs for safety reasons. The lipid fraction showed significant amounts of linoleic acid and phytosterols (7.0 and 12.1% of lipid fraction). Noticeable levels of POPs (114.11 mg/100 g CS) were found, and the phytosterol oxidation rate varied from 27.6 to 48.1%. The OTA content was 18.7-34.4 µg/kg CS, which is about 3 times higher than the European Commission limits for coffee products. The results suggest that CS could be used as a source of cellulose and/or bioactive compounds; however, the contents of POPs and OTA might represent a risk for human safety if intended for human or livestock use.


Assuntos
Coffea/química , Extratos Vegetais/química , Resíduos/análise , Antioxidantes/química , Antioxidantes/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Micotoxinas/análise , Ocratoxinas/análise , Extratos Vegetais/isolamento & purificação
17.
J Sep Sci ; 37(20): 2911-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25069661

RESUMO

A Fast gas chromatography and mass spectrometry method for plant sterols/stanols analysis was developed, using a short capillary gas chromatography column (10 m × 0.1 mm internal diameter × 0.1 µm film thickness) coated with 5% diphenyl-polysiloxane. A silylated mixture of the main plant sterols/stanols standards (ß-sitosterol, campesterol, stigmasterol, campestanol, sitostanol) was well separated in 1.5 min, with a good peak resolution (>1.4, determined on a critical chromatographic peak pair (ß-sitosterol and sitostanol)), repeatability (<13%), and sensitivity (<0.017 ng/mL). The suitability of this Fast chromatography method was tested on plant sterols/stanols-enriched dairy products (yogurt and milk), which were subjected to lipid extraction, cold saponification, and silylation prior to injection. The analytical performance (sensitivity < 0.256 ng/mL and repeatability < 10.36%) and significant reduction of the analysis time and consumables demonstrate that Fast gas chromatography-mass spectrometry method could be also employed for the plant sterols/stanols analysis in functional dairy products.


Assuntos
Laticínios/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fitosteróis/análise , Limite de Detecção , Padrões de Referência , Reprodutibilidade dos Testes
18.
J Agric Food Chem ; 62(1): 279-87, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24313544

RESUMO

The effectiveness of grape seed extract (GSE) encapsulated in liposomes to inhibit the formation of heterocyclic aromatic amines (HAA) during frying of beef patties was assessed. All liposomal systems were prepared by high pressure homogenization at 22 500 psi. A total of six samples (rapeseed oil (control), GSE at 0.1% and 0.2%, and GSE-containing liposomes with 1%, 2%, and 5% soy lecithin) were investigated. MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline), PhIP (2-amino-1-methyl-6-phenylimidazo[4,5b]pyridine), Norharman, and Harman were found after the marinade application and frying. PhIP concentrations decreased upon marination with GSE (0.1%) and GSE-containing liposomes (1% and 5%) (p < 0.05). MeIQx contents decreased in all samples compared to the oil control (p < 0.01) while no effect on ß-carboline formation was observed. Results are in contrast to previous studies that had shown that liposomal encapsulation may enhance effectiveness of polyphenols to inhibit radical reactions. A mechanistic model was proposed to explain the observed differences.


Assuntos
Aminas/química , Antioxidantes/química , Culinária , Extrato de Sementes de Uva/química , Compostos Heterocíclicos/química , Carne/análise , Animais , Bovinos , Temperatura Alta , Lipossomos/química
19.
Meat Sci ; 88(2): 271-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21295921

RESUMO

The aim of this research work was to evaluate the oxidative stability of pork meat lipids as related to dietary supplementation with high-oleic sunflower oil (HOSO) and/or α-tocopheryl acetate (VE), as well as the influence of storage conditions. Four different diets (control; HOSO; VE; HOSO+VE), were fed to swines until slaughtering. Meat slices were packed in vessels with transparent shrink film and exposed to white fluorescent light for 3 days at 8 °C. HOSO supplementation increased oleic acid content of pork meat. The highest levels of peroxide value (PV) and cholesterol oxidation products (COPs) were detected in the control group, whereas HOSO-enriched diets displayed the highest thiobarbituric reactive substance (TBARs) content. After storage under light exposure, pork meat slices exhibited a decrease of PV, which resulted in an increasing trend of TBARs and COPs. Feeding enrichment with both HOSO and vitamin E can be, therefore, used as an appropriate supplementation strategy to produce pork meat with a suitable oxidative stability.


Assuntos
Gorduras na Dieta/metabolismo , Manipulação de Alimentos/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Carne/análise , Ácido Oleico/farmacologia , Óleos de Plantas/farmacologia , Vitamina E/farmacologia , Animais , Colesterol/metabolismo , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Helianthus/química , Luz , Ácido Oleico/análise , Óleo de Girassol , Suínos/metabolismo , Temperatura , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
20.
J Agric Food Chem ; 57(24): 11517-27, 2009 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-20000852

RESUMO

Lipid oxidation and antioxidant capacity of freeze-dried egg yolks produced with two rearing systems (battery cages and free-range) and two types of feedings (conventional and organic) were studied. Nine fresh egg yolks of each crossed treatment were pooled, frozen for a month, freeze-dried, vacuum-packed, and kept at -18 degrees C until analysis. No significant differences were observed in the lipid (58.0-62.1%) and total sterol contents (33.0-35.5 g/kg of lipids) of the freeze-dried egg yolks. Free rearing and conventional feeding systems resulted in significantly higher total tocopherol, alpha-tocopherol, and lutein contents, as compared to the battery cage and the organic feed, respectively. However, no significant differences were found in lipid oxidation (peroxide value = 0.7-0.9 mequiv of O(2)/kg of fat; thiobarbituric reactive substances = 1.0-1.3 mg of malonylaldehyde/kg of sample) and cholesterol oxidation (28.8-43.5 mg of cholesterol oxidation products/kg of lipids; 0.08-0.12% oxidized cholesterol) of freeze-dried egg yolks except for 7alpha-hydroxycholesterol, which was significantly lower in samples obtained with organic feed.


Assuntos
Criação de Animais Domésticos/métodos , Antioxidantes/análise , Galinhas , Gema de Ovo/química , Peroxidação de Lipídeos , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Gorduras na Dieta/análise , Liofilização , Abrigo para Animais , Luteína/análise , Esteróis/análise , Tocoferóis/análise
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