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1.
Foods ; 11(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35627092

RESUMO

Commercially available Irish edible brown (Himanthalia elongata­sea spaghetti (SS), Alaria esculenta­Irish wakame (IW)) and red (Palmaria palmata­dulse (PP), Porphyra umbilicalis­nori) seaweeds were incorporated into pork sausages at 1%, 2.5%, and 5%. Proximate composition, salt, water-holding (WHC), cook loss, instrumental colour analysis, texture profile analysis (TPA), and sensory analysis were examined. Protein (13.14−15.60%), moisture (52.81−55.71%), and fat (18.79−20.02%) contents of fresh pork sausages were not influenced (p > 0.05) by seaweed type or addition level. The ash content of pork sausages containing PP, SS, and IW at 2.5% and 5%, and nori at 5%, were higher (p < 0.05) than the control sample. In comparison to the control, sausages containing nori, SS, and IW at 5% displayed higher (p < 0.05) WHC. Cook loss was unaffected (p > 0.05) by the addition of seaweeds into sausage formulations, compared to the control and within each seaweed. The addition of seaweeds into sausages had an impact on the surface colour (L* a* b*) and texture profile analysis (TPA) at different inclusion levels. Overall, hedonic sensory acceptability decreased (p < 0.05) in cooked sausages containing PP at 2.5% and 5%, and SS and IW at 5%.

2.
Foods ; 10(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34829067

RESUMO

Irish edible brown (Himanthalia elongata-sea spaghetti, Alaria esculenta-Irish wakame) and red seaweeds (Palmaria palmata-dulse, Porphyra umbilicalis-nori) were assessed for nutritional (proximate composition; salt; pH; amino acid; mineral and dietary fibre contents); bioactive (total phenolic content (TPC) and in vitro antioxidant activity (DPPH and FRAP)); thermal (thermogravimetric analysis (TGA)); and technological (water holding capacity (WHC), oil holding capacity (OHC) and swelling capacity (SC)) properties. Red seaweeds had higher (p < 0.05) protein levels, whereas brown seaweeds possessed higher (p < 0.05) moisture, ash, insoluble and total dietary fibre contents. Nori had the lowest (p < 0.05) salt level. Seaweed fat levels ranged from 1 to 2% DW. Aspartic and glutamic acids were the most abundant amino acids. The total amino acid (TAA) content ranged from 4.44 to 31.80%. Seaweeds contained numerous macro (e.g., Na) and trace minerals. The TPC, DPPH and FRAP activities followed the order: sea spaghetti ≥ nori > Irish wakame > dulse (p < 0.05). TGA indicated maximum weight loss at 250 °C. Dulse had the lowest (p < 0.05) WHC and SC properties. Dulse and nori had higher (p < 0.05) OHC than the brown seaweeds. Results demonstrate the potential of seaweeds as functional food product ingredients.

3.
Sci Rep ; 11(1): 16180, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376766

RESUMO

Cardoon meal is a by-product of oil extraction from the seeds of Cynara cardunculus and can serve as a novel alternative feedstuff for ruminants. This study examined the rumen fermentation, biohydrogenation of fatty acids (FA) and microbial community in lambs fed a concentrate diet containing 15% dehydrated lucerne (CON, n = 8) or cardoon meal (CMD, n = 7) for 75 days pre-slaughter. Diets did not influence rumen fermentation characteristics and the abundance of bacteria, methanogens, fungi, or protozoa. Rumen digesta in CMD-fed lambs displayed a higher concentration of total saturated FA and lower total odd- and branched-chain FA and monounsaturated FA. Feeding CMD decreased total trans-18:1 isomer and the ratio of trans-10 to trans-11 C18:1, known as the "trans-10 shift". Amplicon sequencing indicated that the rumen bacterial community in CMD-fed lambs had lower diversity and a higher relative phyla abundance of Proteobacteria at the expense of Bacteroidetes and Fibrobacteres. At the genus level, CMD mediated specific shifts from Prevotella, Alloprevotella, Solobacterium and Fibrobacter to Ruminobacter, suggesting that these genera may play important roles in biohydrogenation. Overall, these results demonstrate that cardoon meal can be used as a feedstuff for ruminants without negatively affecting rumen fermentation and microbiota but its impact on biohydrogenation may influence the FA composition in meat or milk.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Cynara/fisiologia , Dieta/veterinária , Ácidos Graxos/análise , Refeições , Rúmen/metabolismo , Animais , Cynara/classificação , Fermentação , Hidrogenação , Rúmen/microbiologia , Ovinos
4.
J Sci Food Agric ; 101(11): 4768-4778, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33502758

RESUMO

BACKGROUND: Concentrate supplementation of a grass silage-based ration is a typical practice employed for indoor winter finishing of beef cattle in many temperate countries. Plant by-products, such as dried corn gluten feed (CGF), can be used to replace conventional feedstuffs in a concentrate supplement to enhance the sustainability of ruminant production systems and to improve meat quality. This study examined the chemical composition, fatty acid profile, oxidative stability and sensory attributes of beef (longissimus thoracis muscle) from steers offered grass silage and concentrate supplements containing varying levels (0%, 25%, 50%, 75%) of CGF substituted for barley / soybean meal. RESULTS: Feeding 50%CGF decreased the protein content and increased intramuscular fat in comparison with 25%CGF. Total phenol content and iron-reducing antioxidant power followed the order: 0%CGF > 50%CGF and 25%CGF > 0%CGF = 50%CGF, respectively. Compared to 0%CGF, 25%CGF and 75%CGF decreased C14:0 and increased C22:2n-6, C20:5n-3 and total n-3 polyunsaturated fatty acids whereas 75%CGF increased conjugated linoleic acids and C18:3n-3. Diet did not affect the oxidative stability and sensory attributes of beef patties. CONCLUSION: The inclusion of up to 75%CGF in a supplementary concentrate for steers increased the proportion of health-promoting unsaturated fatty acids without negatively influencing the shelf-life and eating quality of longissimus thoracis muscle. © 2021 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Músculos do Dorso/metabolismo , Bovinos/metabolismo , Ácidos Graxos/química , Glutens/metabolismo , Poaceae/metabolismo , Zea mays/metabolismo , Animais , Músculos do Dorso/crescimento & desenvolvimento , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Ácidos Graxos/metabolismo , Hordeum/metabolismo , Humanos , Masculino , Carne/análise , Silagem/análise , Glycine max/metabolismo , Paladar
5.
Meat Sci ; 173: 108381, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33288361

RESUMO

Thirty-six steers were randomly assigned to one of three dietary treatments fed ad libitum grass silage and concentrate supplements containing either barley/soybean meal (CON), 80% DM corn (CDGS)- or 80% DM wheat (WDGS)-dried distillers' grains with solubles for 124 days pre-slaughter. Chemical and fatty acid composition, shelf-life, and eating quality of longissimus thoracis muscle were determined. Dietary CDGS and WDGS increased the proportion of conjugated linoleic acids (P < 0.05) and tended to increase C18:3n-3 (P = 0.075) and total polyunsaturated fatty acids (P = 0.060) relative to the CON. Feeding diets containing distillers' grains reduced the lipid and colour stability of fresh beef patties stored in modified atmosphere packs (MAP), with CDGS exhibiting an intermediate effect between CON and WDGS. Diet did not negatively influence the texture profile parameters and eating quality attributes of beef stored in MAP. The inclusion of CDGS or WDGS in supplementary concentrates may improve the fatty acid profile but decreased the shelf-life of beef.


Assuntos
Bovinos/fisiologia , Dieta/veterinária , Grão Comestível , Carne Vermelha/análise , Ração Animal/análise , Animais , Ácidos Graxos/análise , Masculino , Músculo Esquelético/química , Silagem
6.
Meat Sci ; 168: 108181, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32417672

RESUMO

This study investigated the quality composition, oxidative stability and sensory attributes of beef (longissimus thoracis, LT) from steers offered grass silage and a concentrate supplement in which barley was replaced by 40% and 80% (as-fed basis) of dried citrus pulp (DCP). Dietary treatment did not influence the antioxidant status (α-tocopherol and total phenolic contents) and activities of LT (radical scavenging activity, ferric reducing antioxidant power and iron chelating activity). Feeding DCP significantly increased the proportion of conjugated linoleic acids and polyunsaturated fatty acids in beef. Lipid and colour stability of fresh beef patties stored in modified atmosphere packs (MAP) were unaffected by dietary treatment but feeding 40% DCP reduced (P < .05) lipid oxidation in aerobically-stored cooked beef patties. Beef patties stored in MAP for up to 7 days were assessed by sensory panellists to be juicier for those fed 40% DCP compared to 0% and 80% DCP. Results indicated that substitution of barley with DCP improved the fatty acid profiles of beef without negatively influencing the eating quality of beef.


Assuntos
Ração Animal/análise , Citrus , Carne Vermelha/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/fisiologia , Dieta/veterinária , Qualidade dos Alimentos , Humanos , Masculino , Produtos da Carne/análise , Músculo Esquelético/química , Silagem
7.
Glob Chang Biol ; 26(5): 2878-2896, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32103581

RESUMO

With rapid global change, organisms in natural systems are exposed to a multitude of stressors that likely co-occur, with uncertain impacts. We explored individual and cumulative effects of co-occurring environmental stressors on the striking, yet poorly understood, phenomenon of facultative migration. We reared offspring of a brown trout population that naturally demonstrates facultative anadromy (sea migration), under different environmental stressor treatments and measured life history responses in terms of migratory tactics and freshwater maturation rates. Juvenile fish were exposed to reduced food availability, temperatures elevated to 1.8°C above natural conditions or both treatments in combination over 18 months of experimental tank rearing. When considered in isolation, reduced food had negative effects on the size, mass and condition of fish across the experiment. We detected variable effects of warm temperatures (negative effects on size and mass, but positive effect on lipids). When combined with food restriction, temperature effects on these traits were less pronounced, implying antagonistic stressor effects on morphological traits. Stressors combined additively, but had opposing effects on life history tactics: migration increased and maturation rates decreased under low food conditions, whereas the opposite occurred in the warm temperature treatment. Not all fish had expressed maturation or migration tactics by the end of the study, and the frequency of these 'unassigned' fish was higher in food deprivation treatments, but lower in warm treatments. Fish showing migration tactics were smaller and in poorer condition than fish showing maturation tactics, but were similar in size to unassigned fish. We further detected effects of food restriction on hypo-osmoregulatory function of migrants that may influence the fitness benefits of the migratory tactic at sea. We also highlight that responses to multiple stressors may vary depending on the response considered. Collectively, our results indicate contrasting effects of environmental stressors on life history trajectories in a facultatively migratory species.


Assuntos
Migração Animal , Truta , Animais , Água Doce , Temperatura
8.
Meat Sci ; 161: 108001, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31756515

RESUMO

The optimization of processed meats through salt replacement using edible seaweeds may reduce the risk of chronic disease through reduction in dietary sodium. We investigated the impact of the inclusion of four selected seaweeds (1% w/w) in reformulated frankfurters in which salt addition and pork fat content was reduced by 50% and 21%, respectively, and where pork loin (longissimus dorsi muscle) was increased by 6%, compared to a Control. Two different types of red (Porphyra umbilicalis and Palmaria palmata) and brown (Himanthalia elongata and Undaria pinnatifida) edible seaweeds were evaluated. The reformulated frankfurters containing added seaweed were lower in ash, higher in moisture, protein and darker in colour and had altered textural properties in comparison to the Control; mainly less hard and less chewy. The volatile and sensory profiles of the reformulated frankfurters differed from the Control. However, the reformulated frankfurters with the inclusion of H.elongata were the most promising, although further work is required to optimise the formulation.


Assuntos
Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Produtos da Carne/análise , Carne de Porco/análise , Alga Marinha/química , Cloreto de Sódio na Dieta/administração & dosagem , Compostos Orgânicos Voláteis/análise , Animais , Cor , Dieta Hipossódica , Microbiologia de Alimentos/métodos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Cloreto de Sódio/química , Suínos , Compostos Orgânicos Voláteis/química
9.
Meat Sci ; 153: 126-134, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30927684

RESUMO

Fatty acids and oxidative stability were determined in meat from lambs fed a diet containing 15% dehydrated alfalfa (CON, n = 8) or cardoon meal (CMD, n = 7). Furthermore, the antioxidant activity of a phenolic-rich cardoon meal extract (1.32 GAE mg/ml) was examined in muscle homogenates (0, 0.5, 1, 5% v/w) subjected to iron/ascorbate-induced oxidation. Feeding CMD did not affect lamb performances and carcass traits but reduced (P < 0.05) the vaccenic and rumenic acids and increased stearic acid in muscle. Lipid oxidation was higher in raw meat from the CMD-fed lambs after 7 days of storage (P < 0.05). Feeding CMD did not affect the colour stability of raw meat and the oxidative stability of cooked meat and of muscle homogenates incubated with pro-oxidant catalysts. Adding 5% cardoon extract in muscle homogenates increased (+114.3%; P = 0.03) the total phenolic content and reduced (-77.6%; P < 0.01) lipid oxidation, demonstrating the antioxidant potential of compounds present in cardoon meal.


Assuntos
Ração Animal/análise , Antioxidantes/análise , Cynara , Carneiro Doméstico/crescimento & desenvolvimento , Animais , Cor , Culinária , Dieta/veterinária , Ácidos Graxos/análise , Músculo Esquelético/química , Oxirredução , Carne Vermelha/análise
10.
FEMS Microbiol Ecol ; 94(5)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29648587

RESUMO

This study characterised the response of ruminal fermentation and the rumen microbiome in lambs fed commercial vegetal sources of hydrolysable tannins (HT) and condensed tannins (CT). Forty-four lambs (19.56 ± 2.06 kg) were randomly assigned to either a concentrate diet (CON, n = 8) or CON supplemented with 4% of two HT [chestnut (Castanea sativa, HT-c) and tara (Caesalpinia spinosa, HT-t)] and CT [mimosa (Acacia negra, CT-m) and gambier (Uncaria gambir, CT-g)] extracts (all, n = 9) for 75 days pre-slaughter. Tannin supplementation did not influence ruminal fermentation traits. Quantitative PCR demonstrated that tannins did not affect the absolute abundance of ruminal bacteria or fungi. However, CT-m (-12.8%) and CT-g (-11.5%) significantly reduced the abundance of methanogens, while HT-t (-20.7%) and CT-g (-20.8%) inhibited protozoal abundance. Ribosomal amplicon sequencing revealed that tannins caused changes in the phylogenetic structure of the bacterial and methanogen communities. Tannins inhibited the fibrolytic bacterium, Fibrobacter and tended to suppress the methanogen genus, Methanosphaera. Results demonstrated that both HT and CT sources could impact the ruminal microbiome when supplemented at 4% inclusion level. HT-t, CT-m and CT-g extracts displayed specific antimicrobial activity against methanogens and protozoa without compromising ruminal fermentation in a long-term feeding trial.


Assuntos
Bactérias/isolamento & purificação , Suplementos Nutricionais/análise , Microbioma Gastrointestinal , Taninos Hidrolisáveis/metabolismo , Proantocianidinas/metabolismo , Rúmen/microbiologia , Ovinos/metabolismo , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Dieta/veterinária , Fermentação , Filogenia , Rúmen/metabolismo , Ovinos/microbiologia
11.
Food Chem ; 256: 18-24, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606435

RESUMO

This study investigates dietary fortification of heifer feeds with cholecalciferol and ergocalciferol sources and effects on beef total vitamin D activity, vitamer, respective 25-hydroxymetabolite contents, and meat quality. Thirty heifers were allocated to one of three dietary treatments [(1) basal diet + 4000 IU of vitamin D3 (Vit D3); (2) basal diet + 4000 IU of vitamin D2 (Vit D2); and (3) basal diet + 4000 IU of vitamin D2-enriched mushrooms (Mushroom D2)] for a 30 day pre-slaughter period. Supplementation of heifer diets with Vit D3 yielded higher (p < 0.001) Longissimus thoracis (LT) total vitamin D activity (by 38-56%; p < 0.05) and serum 25-OH-D concentration (by 20-36%; p < 0.05), compared to that from Vit D2 and Mushroom D2 supplemented animals. Irrespective of vitamin D source, carcass characteristics, sensory and meat quality parameter were unaffected (p > 0.05) by the dietary treatments. In conclusion, vitamin D3 biofortification of cattle diets is the most efficacious way to enhance total beef vitamin D activity.


Assuntos
Agaricales/efeitos da radiação , Colecalciferol/administração & dosagem , Ergocalciferóis/administração & dosagem , Alimentos Fortificados/análise , Carne/análise , Raios Ultravioleta , Agaricales/metabolismo , Animais , Músculos do Dorso/química , Músculos do Dorso/metabolismo , Calcifediol/análise , Calcifediol/sangue , Cálcio/sangue , Bovinos , Colecalciferol/síntese química , Cromatografia Líquida de Alta Pressão , Dieta/veterinária , Ergocalciferóis/metabolismo , Espectrometria de Massas em Tandem
12.
Meat Sci ; 134: 103-110, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28779716

RESUMO

This study investigated the effects of cholecalciferol (vitamin D3) supplementation on beef vitamin D activity, beef tenderness and sensory attributes. Thirty heifers were randomly allocated to one of three finishing dietary treatments [(T1) basal diet+0IU vitamin D3; (T2) basal diet+2000IU vitamin D3; and (T3) basal diet+4000IU vitamin D3] for a 30day period pre-slaughter. Vitamin D3 supplementation linearly increased serum 25-hydroxyvitamin D3 (25-OH-D3) concentrations (R2=0.48), Longissimus thoracis (LT) total vitamin D activity (R2=0.78) as well as individually vitamin D3 (R2=0.84) and 25-OH-D3 (R2=0.75). The highest vitamin D3 inclusion diet (T3) had a 42% increase (P<0.001) in LT vitamin D activity compared to the intermediate diet (T2) and a 145% increase over the lowest level diet (T1). Vitamin D3 supplementation decreased LT shear (P<0.05) force values after 14days chilling. Sensory parameters were not affected (P>0.05). In conclusion, through short-term vitamin D3 supplementation of cattle diets, beef vitamin D activity can successfully be enhanced.


Assuntos
Ração Animal/análise , Suplementos Nutricionais/análise , Vitamina D/análise , Adulto , Animais , Cálcio/sangue , Bovinos , Colecalciferol/farmacologia , Dieta/veterinária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/química , Odorantes , Carne Vermelha , Paladar , Vitamina D/sangue
13.
Mar Drugs ; 13(4): 2447-64, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25903283

RESUMO

The anti-oxidative potential of laminarin (L), fucoidan (F) and an L/F seaweed extract was measured using the DPPH free radical scavenging assay, in 25% pork (longissimus thoracis et lumborum (LTL)) homogenates (TBARS) (3 and 6 mg/mL) and in horse heart oxymyoglobin (OxyMb) (0.1 and 1 mg/mL). The DPPH activity of fresh and cooked minced LTL containing L (100 mg/g; L100), F100 and L/F100,300, and bioaccessibility post in vitro digestion (L/F300), was assessed. Theoretical cellular uptake of antioxidant compounds was measured in a transwell Caco-2 cell model. Laminarin displayed no activity and fucoidan reduced lipid oxidation but catalysed OxyMb oxidation. Fucoidan activity was lowered by cooking while the L/F extract displayed moderate thermal stability. A decrease in DPPH antioxidant activity of 44.15% and 36.63%, after 4 and 20 h respectively, indicated theoretical uptake of L/F antioxidant compounds. Results highlight the potential use of seaweed extracts as functional ingredients in pork.


Assuntos
Antioxidantes/química , Enterócitos/metabolismo , Conservantes de Alimentos/química , Glucanos/química , Absorção Intestinal , Produtos da Carne/análise , Polissacarídeos/química , Animais , Antioxidantes/metabolismo , Células CACO-2 , Culinária , Carboidratos da Dieta/metabolismo , Digestão , Conservantes de Alimentos/metabolismo , Qualidade dos Alimentos , Armazenamento de Alimentos , Glucanos/metabolismo , Temperatura Alta/efeitos adversos , Humanos , Laminaria/química , Metabolismo dos Lipídeos , Mioglobina/química , Oxirredução , Polissacarídeos/metabolismo , Alga Marinha/química , Sus scrofa
14.
J Med Food ; 12(4): 893-901, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19735192

RESUMO

Interest exists in the manufacture of meat products with added functional ingredients to enhance consumer health. Because experimental evidence suggests that many herbs and spices, particularly those of the Lamiaceae family such as Salvia officinalis L. (sage) and Origanum vulgare L. (oregano), possess a wide range of biological and pharmacological activities, they represent promising functional ingredients for incorporation into meat and meat products. The present study aimed to determine the bioactivity of cooked beef patties that were enriched with or without sage or oregano extracts (1,200 microg/g). Cooked beef patties were subjected to an in vitro digestion procedure, and the resulting micelles isolated from the digested meats were added to human intestinal Caco-2 cells. The antioxidant potential (ferric reducing antioxidant power [FRAP] value) of enriched beef patties was significantly higher than the FRAP value of non-enriched beef patties, both before and after in vitro digestion. Cell viability significantly increased following treatment with certain concentrations of the micelle fractions from digested sage- or oregano-enriched beef patties. Pretreatment with micelles derived from sage- or oregano-enriched beef patties did not significantly protect against cell injury or DNA damage induced by H(2)O(2). However, micelles derived from digested sage-enriched beef patties (10% vol/vol) significantly increased cellular reduced glutathione (GSH) content. In addition, micelles derived from both sage- and oregano-enriched beef patties (10% vol/vol) significantly protected against H(2)O(2)-induced GSH depletion. Thus, it appears that sage and oregano exhibit some bioactivity within a meat system. Our findings suggest that herbal extracts have potential as possible functional ingredients in meat products.


Assuntos
Antioxidantes/farmacologia , Glutationa/metabolismo , Carne , Origanum , Extratos Vegetais/farmacologia , Salvia officinalis , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio , Micelas , Especiarias
15.
J Med Food ; 9(2): 187-95, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16822204

RESUMO

Phytochemicals and plant extracts, present in fruit, vegetables, plants, herbs, and beverages, have been shown to have antioxidant potential that may modulate the etiology of certain chronic diseases. The objective of the present study was to determine the concentration of compound that inhibited cell growth by 50% (IC(50)) of a range of phytochemicals and plant extracts and to investigate their antioxidant and genoprotective effects under conditions of oxidative stress in U937 cells. Two phytochemicals-resveratrol and citroflavan-3-ol-and four plant extracts-grapeseed polyphenols, olive leaf extract, bearberry, and Echinacea purpurea-were examined. Viability was assessed by the fluorescein diacetate/ethidium bromide assay. The IC(50) was calculated. To examine their antioxidant and genoprotective effects, U937 cells were pretreated with the test compounds at levels below the IC(50) and then exposed to oxidants: 0.5 microM etoposide or 100 microM hydrogen peroxide (H(2)O(2)) or 400 microM tert-butylhydroperoxide (tBOOH). Cellular reduced glutathione levels were measured as an indicator of oxidative stress. DNA damage was assessed by the alkaline single-cell gel electrophoresis assay or comet assay. Resveratrol demonstrated the highest IC50 value of 13.7 microg/mL, with Echinacea the lowest at 9,400 microg/mL. Etoposide-induced oxidative stress was strongly reduced by olive leaf extract and bearberry. Grapeseed polyphenols and bearberry strongly protected against H2O2- and tBOOH-induced DNA damage. In conclusion, these results provide evidence that non-nutrient dietary constituents may act as significant bioactive compounds and that plant extracts, such as bearberry, grapeseed polyphenols, and olive leaf extract, strongly protect against oxidative stress.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Estilbenos/farmacologia , Arctostaphylos/química , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Echinacea/química , Humanos , Peróxido de Hidrogênio/farmacologia , Olea , Fenóis/farmacologia , Folhas de Planta/química , Polifenóis , Resveratrol , Sementes/química , Células U937 , Vitis/química , terc-Butil Hidroperóxido/farmacologia
16.
Meat Sci ; 69(4): 773-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22063156

RESUMO

The effects of addition of tea catechins (TC) and vitamin C (VC) on sensory evaluation, colour and lipid stability in cooked or raw beef and chicken meat patties during refrigerated storage were studied. Fresh beef striploin and chicken breast muscles were minced, following removal of external fat and connective tissue. Following mincing, beef and chicken were assigned to one of the following five treatments: control (meat treated with no antioxidant); TC200, meat plus 200 mg TC/kg muscle; TC400, meat plus 400 mg TC/kg muscle; VC200, meat plus 200 mg VC/kg muscle, VC400, meat plus 400 mg VC/kg muscle. Sodium chloride (1%) was added to all samples. Patties (125 g portions), formed from the above-treated minced meat, were oven cooked, cooled, and packaged in 30% CO(2):70% N(2). Fresh raw beef and chicken patties were packaged in 80% O(2):20% CO(2). All samples were stored for up to 7 days under fluorescent lighting at 4 °C. Sensory parameters (colour, flavour, taste, tenderness and overall acceptability) were evaluated on cooked beef and chicken patties after 1, 3 and 6 days of storage. Surface colour (Hunter L, a and b values), and lipid oxidation (2-thiobarbituric acid reactive substances) were measured on days 1, 3 and 6 of storage for cooked meats and on days 2 and 7 for raw beef and chicken. Tea catechins addition (200 or 400 mg/kg) to minced meat caused (P<0.05) discolouration in cooked beef and chicken meat patties and significantly reduced (P<0.001) lipid oxidation in cooked or raw beef patties compared to the control. Beef, either raw or cooked, was more susceptible (P<0.01) to oxidation compared to chicken. Raw meat stored in high oxygen conditions was more susceptible to lipid oxidation than cooked meat stored in anaerobic conditions. Tea catechins treatments (TC200 and TC400) inhibited (P<0.05) lipid oxidation in raw beef to a greater extent than vitamin C treatments (VC200 and VC400). These results indicate that tea catechins are potent natural antioxidants and exhibit greater antioxidant efficacy compared to vitamin C.

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