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An experiment was conducted to assess the effect of natural antioxidants (black pepper, green tea, roselle and their combinations) on meat quality of broiler chickens. A total of 270 1 - day old Arbor Acre broiler chicks were randomly distributed into nine treatments of three replicates each (10 birds in each replicate) in a 2 x 5 factorial arrangement for 2 inclusion levels (0.5g and 1.0g per kg of feed) of natural antioxidants (Control (CT), Green tea (GT), Roselle (RS), Black pepper (BP) and combination (CM) of the 3 antioxidants). At the end of the feeding trial (at 8 weeks), nine birds per treatment were immobilized, slaughtered, dressed, weighed and cut into primal cuts. The growth (initial and final body weight gain, average daily feed intake and weight gain, and feed conversion) and blood assay (haematology and serum biochemistry) of the birds were monitored while the breast and thigh meat cuts were subjected to physico-chemical and sensory analysis. The result indicated that, among examined natural antioxidants, BP improved the bird抯 live weight. High Density Lipoprotein value was highest (p<0.05) in control and closely followed by birds on GT, CM, BP and RS. The lowest blood (p<0.05) cholesterol was recorded in RS which was closely followed by GT and CM. Carcass evaluation showed that birds fed BP had better (p<0.05) live weight (2.05kg) and highest acceptability (p<0.05) for organoleptic properties. The breast meat weight was also highest (p<0.05) in BP. It was concluded that the natural antioxidants increased live weight, improved performance and reduced abdominal fat. RS reduced blood cholesterol while RS, CM (GT + RS + BP) inclusion improved serum total protein of broiler chickens. Inclusion of natural antioxidant in the diets of broiler is hereby advocated for achieving optimum broilers performance and meat quality.
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This study expounded the great impacts of excess energy intake and oxidative inflammation on national health in China and put forward the pathological mirror-image hypothesis of the relationship between obesity and oxidative inflammation. On this basis, an ideological framework was constructed to deal with oxidative stress and oxidative inflammation centered on the development of natural antioxidant products. The study contained the following four parts: the ways to improve national health in China; the promotion of cognition to oxidative inflammation to improve national health in China; prospects for the prevention and treatment of oxidative inflammation in China; the reason why Northwest Yunnan is a good place to develop high-quality natural antioxidants.
Subject(s)
Humans , China , Energy Intake , Inflammation , Oxidation-Reduction , Oxidative StressABSTRACT
Spiranthera odoratissima A. St.-Hil (Rutaceae), a shrub whose common name is manacá do Cerrado in Brazilian Portuguese, is about 1-m high and has been used by folk medicine to treat stomachache, kidney and liver infections, headache, rheumatism and as a blood purifier. This study aimed at preparing hexane, ethyl acetate, methanolic, hydroethanolic and aqueous extracts from S. odoratissima leaves, at carrying out preliminary phytochemical screening and at evaluating their in vitroantioxidant and anti-Listeria monocytogenesactivities. Antioxidant activity was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azinobis-3-ethybenzothiazoline-6-sulfonate) and FRAP (ferric reducing antioxidant power) methods. Antibacterial activity was investigated against L. monocytogenesand Minimum Inhibitory Concentration (MIC) values of plant extracts were calculated by the broth microdilution method with the use of 96-well plates. In aqueous, methanolic, hydroethanolic, ethyl acetate and hexane extracts from S. odoratissima leaves, the following classes of compounds were investigated: organic acids, reducing sugars, flavonoids, saponin compounds, coumarin compounds, phenolics, tannins, purine compounds, catechins, flavonol derivatives, sesquiterpene lactonesand anthraquinones. All plant extracts, except the hexane one, exhibited high antioxidant activity. Regarding antibacterial activity, the most polar extracts showed high activity against L. monocytogenes; their MIC values ranged between 12.5 and 62.5 μg mL-1, while the hexane one exhibited low activity (MIC = 1000 μgmL-1). In short, extracts from S. odoratissima leaves may be consideredpromising sources of secondary metabolites with relevant antioxidant and antibacterial activities.
Subject(s)
Antioxidants , Listeria monocytogenes/immunology , Rutaceae/chemistryABSTRACT
Abstract: This article describes the chemical composition of Vernonia chalybaea essential oil, and investigates its antimicrobial, antioxidant and hemolytic activities. The evaluation of the antifungal activity was performed by the broth microdilution method using strains of yeasts and dermatophytic fungi. The checkerboard technique to find antimicrobial modulatory effects was performed using ketoconazole as standard drug. The antioxidant activity was evaluated by DPPH scavenging assay and β-carotene/linoleic-acid system. The toxicity was characterized by the brine shrimp lethality test and hemolysis bioassays. The essential oil was obtained by hydrodistillation and analyzed by GC-MS method, showing to be rich in the sesquiterpenes β-caryophyllene (39.06%) and bicyclogermacrene (19.69%), and also demonstrated a relevant antifungal activity against strains of Trichophyton rubrum. In the modulatory activity assay, the essential oil of V. chalybaea and β-caryophyllene demonstrated a synergistic interaction with ketoconazole, with increasing of its antifungal action. The antioxidant activity was evidenced mainly by β-carotene/linoleic acid system, with IC50 value of 35.87 ± 0.32 µg/mL. The results suggest that V. chalybaea essential oil and β-caryophyllene are valuable natural medicinal agents with antioxidant and antimicrobial activities.
Subject(s)
Humans , Animals , Oils, Volatile/pharmacology , Vernonia/chemistry , Ketoconazole/pharmacology , Antifungal Agents/pharmacology , Artemia , Bacteria/drug effects , Oils, Volatile/chemistry , Linoleic Acid/pharmacology , beta Karyopherins/pharmacology , Fungi/classification , Fungi/drug effects , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemistry , Antioxidants/pharmacologyABSTRACT
@#Introduction: There are numerous studies on the therapeutic properties of Artocarpus heterophyllus. However, studies on the aqueous extraction of A. heterophyllus leaves are limited. This present study was conducted to optimize the extraction conditions of A. heterophyllus leaves to yield the highest phenolic, flavonoids and antioxidant contents. Methods: Response surface methodology (RSM) was employed to obtain a higher phenolic extraction parameter(s) of A. heterophyllus leaves using Central Composite Design (CCD). The antioxidant activity was then determined via ABTS (2,29-azinobis (3 ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay and analysis of the individual phenolics was performed by high performance liquid chromatography (HPLC). Results: The optimum extraction conditions with higher phenolics content and antioxidant activity was achieved at 81°C, 100 min and 40 mL/g sample with a good desirability value of 0.87. Under these optimized parameters, total phenolics and flavonoids were 174.48 ± 4.05 mg GAE/g sample and 21.44 ± 0.05 mg RE/g sample, respectively. Meanwhile, antioxidant activity via ABTS and DPPH assays were 90.88% ± 0.09 and 87.22% ± 0.62, respectively. Finally, under optimal extraction conditions revealed 4 compounds identified as chlorogenic acid, quercetin, rutin and kaempferol. Conclusion: The optimisation are promising to improve phenolic yield and antioxidant activity in A. heterophyllus leaves. It also proved that A. heterophyllus leaves can be used as an alternative natural antioxidant especially in medicinal applications since all identified compound possess significant biological activities for human health.
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ABSTRACT: The aim of this work was to determine the best extraction condition of bioactive compounds from lemongrass (Cymbopogon citratus), using the conventional method and ultrasonic assisted extraction, varying the temperature, in order to evaluate the antioxidant activity and the antimicrobial activity of the extract with higher antioxidant power in fresh chicken sausages during the storage period. The extracts were obtained by the conventional method (solvent extraction) and by ultrasound assisted extraction, varying the temperature (20°C, 40°C and 60°C). Phenolic compounds, total flavonoids and antioxidant activity were measured by the DPPH, FRAP, ORAC methods. Conventional extraction and ultrasound methods influenced the phenolic and total flavonoid content at all tested temperatures. Conventional and ultrasonic methods did not influence the IC50 at temperatures of 40°C and 60°C. The antioxidant activity by the DPPH method and by the FRAP method was superior in the conventional method at the temperature of 60°C, however by the ORAC method the best results were in the extraction by ultrasound. The results demonstrate that the conventional extraction at 60ºC was better to obtain extracts of lemongrass with greater amount of bioactive compounds. The antimicrobial capacity evaluated in sausage of fresh chicken showed that in the concentration of 1.0% of the extract protected the product as the growth of mesophilic aerobes and against the growth of psychrotrophic bacteria. Lemongrass can be considered as a natural alternative to obtain extracts rich in bioactive compounds, with antioxidant activity and high antimicrobial capacity.
RESUMO: O objetivo deste trabalho foi determinar a melhor condição de extração de compostos bioativos do capim-limão (Cymbopogon citratus), usando o método convencional e extração assistida por ultrassom, em diferentes temperaturas, a fim de avaliar a atividade antioxidante e a atividade antimicrobiana do extrato com maior poder antioxidante em linguiças de frango frescal durante o período de armazenamento. Os extratos foram obtidos pelo método convencional (extração com solvente) e por extração assistida por ultrassom, variando a temperatura (20°C, 40°C e 60°C). Foram medidos os compostos fenólicos, flavonoides totais e atividade antioxidante pelos métodos DPPH, FRAP, ORAC. Os métodos de extração convencional e ultrassom influenciaram no teor de fenólicos e flavonoides totais em todas as temperaturas testadas. Os métodos convencional e ultrassom não influenciaram no IC50 nas temperaturas de 40oC e 60oC. A atividade antioxidante pelo método DPPH e pelo método FRAP foi superior no método convencional na temperatura de 60°C, entretanto pelo método ORAC os melhores resultados foram na extração por ultrassom. Os resultados demonstram que a extração convencional a 60ºC foi melhor para obter extratos de capim-limão com maior quantidade de compostos bioativos. A capacidade antimicrobiana avaliada em linguiça frescal mostrou que na concentração de 1,0% do extrato protegeu o produto quanto o crescimento de aeróbios mesófilos e contra o crescimento de bactérias psicrotróficas. O capim-limão pode ser considerado uma alternativa natural para obtenção de extratos ricos em compostos bioativos, com atividade antioxidante e elevada capacidade antimicrobiana.
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ABSTRACT: There is an increasing consumer demand to avoid the use of synthetic additives like many antioxidants currently added to food. The objective of this study was to determine the effect of spraying ascorbic acid, rosemary extract and a combination of both on pork meat during refrigerated storage. Pork meat with antioxidants sprayed on the surface was packaged under vacuum and stored (4ºC, 45d). pH, color, lipid oxidation, total aerobic count, drip loss and moisture were evaluated during storage. Results suggested that surface application of rosemary extract and a combination of rosemary extract and ascorbic acid resulted in an effective delay of lipid oxidation of pork meat, without affecting pH, colour or water content during storage. No effect of rosemary extract on microbial growth was observed.
RESUMO: Existe uma crescente demanda dos consumidores para evitar o uso de aditivos sintéticos como muitos antioxidantes atualmente adicionados aos alimentos. O objetivo deste estudo foi determinar o efeito da pulverização de ácido ascórbico, extrato de alecrim e uma combinação de ambos na carne de porco durante o armazenamento resfriado. A carne de porco com antioxidantes pulverizados na superfície foi embalada sob vácuo e armazenada (4ºC, 45d). pH, cor, oxidação lipídica, contagem de microrganismos aerobios totais, perda por gotejamento e umidade foram avaliados durante o armazenamento. Os resultados sugerem que a aplicação superficial de extrato de alecrim e uma combinação de extrato de alecrim e ácido ascórbico resultaram no atraso efetivo da oxidação lipídica da carne de porco, sem afetar o pH, cor ou teor de água ao longo do armazenamento. Nenhum efeito do extrato de alecrim no crescimento microbiano foi observado.
ABSTRACT
The objective of this study was to determine the proximal composition, the physical and chemical characteristics and the in vitro antioxidant capacity (DPPH, ABTS and FRAP) of the pulp of the wild passion fruit (Passiflora glandulosa Cav.) from Cariri region, Ceara, Brazil. The results showed that the proximal composition and the caloric value of this passion fruit are similar to other species, but with a high ascorbic acid content. The fruit pulp showed low level of antioxidant activity and low level of polyphenolic compounds followed by three methodologies used. Due to high levels of titratable acidity (3.52) and total soluble solids (17.80° Brix), this fruit can be considered as a high value fruit for commerce. However, it is a species of passion fruit with few studies described in the literature, and more research is needed to assess its nutritional and functional potential.
O objetivo do estudo foi determinar a composição centesimal, as características físicas e químicas e a capacidade antioxidante (DPPH, ABTS e FRAP) in vitro da polpa do maracujá-do-mato (Passiflora glandulosa Cav.) da região do Cariri, Ceará, Brasil. Os resultados demonstraram que a composição centesimal e o valor calórico desse tipo de maracujá são similares a outras espécies, mas com nível elevado de ácido ascórbico. A polpa apresentou baixo teor de polifenóis e baixa atividade antioxidante para as três metodologias aplicadas. Em razão dos altos níveis de acidez titulável (3,52) e sólidos solúveis totais (17,80° Brix), este fruto pode ser considerado como um fruto de alto valor para o comércio. Porém, esta é uma espécie de maracujá pouco descrita na literatura, sendo necessárias mais análises para avaliar seu potencial valor nutricional e funcional.
Subject(s)
Agriculture , Antioxidants , Dietary Fiber , Functional Food , Passiflora , Phenolic CompoundsABSTRACT
Low-acid mayonnaise produced with raw egg is a product rich in oil, almost a home-made product, but it is susceptible to lipid oxidation and microbial contamination by Salmonella Enteritidis, which results in deterioration of the product and forms undesirable components such as free radicals and reactive aldehydes. A better understanding of the factors that affect and can prevent lipid oxidation and microbial growth is essential to improve the product's lifetime. This review presents information on the factors that influence lipid oxidation and can accelerate the proliferation of microorganisms. Monitoring these possible factors can reduce the induction period that accelerates rancidity and ensure microbiological safety of the product, possibly increasing shelf life. The most effective means to slow lipid oxidation in mayonnaise and ensure its safety is the use of antioxidants and antimicrobials. Currently, several synthetic additives are being replaced by natural products such as essential oils. Therefore, to provide a better base for the food industry, an effective antioxidant and antimicrobial system must be designed for mayonnaise(AU)
A maionese de baixa acidez é um produto similar a maionese caseira, produzida com ovo in natura é um produto rico em óleo, susceptível à oxidação lipídica e contaminação microbiana por Salmonella Enteritidis, o que resulta em deterioração do produto e a formação de componentes indesejáveis, tais como os radicais livres e aldeídos reativos. Uma melhor compreensão dos fatores que afetam e que podem prevenir a oxidação de lipídios e multiplicação microbiana é essencial para melhorar o tempo de vida do produto. Esta revisão apresenta o conhecimento dos fatores que influenciam a oxidação lipídica e que podem acelerar a multiplicação de microrganismos. O acompanhamento destes fatores possíveis pode reduzir o período de indução que aceleram o ranço e garantir a segurança microbiológica do produto o que poderia aumentar o tempo de prateleira da maionese. Os meios mais eficazes para retardar a oxidação lipídica na maionese e garantir a sua segurança é a utilização de antioxidantes e antimicrobianos. Atualmente, diversos aditivos sintéticos estão sendo substituídos por produtos naturais, como os óleos essenciais. Portanto, para proporcionar uma melhor base para a indústria alimentar um sistema antioxidante e antimicrobiano eficaz deve ser concebido para maionese(AU)
Subject(s)
Humans , Salmonella/pathogenicity , Oils, Volatile/administration & dosage , Oxidation , Food HandlingABSTRACT
Human papillomavirus infection is now a well-established cause of many common cancers like cervical, other anogenital, and head and neck cancers. The mortality and morbidity rate associated with these cancers constitute a major burden especially for the underdeveloped and developing countries of the world, where they are more common. Traditionally, all these subsites are being treated with different chemoradiation protocols with variable results. Toxicities associated with the standard high dose chemoradiation protocols form a major obstacle in the completion of treatment for these patients and often affects the outcome negatively. Personal experience and published reports and reviews suggests that HPV associated squamous cell cancers are a distinct biological sub group of cancer which can be treated safely with reduced intensity of chemoradiation. The establishment of a similar de-intensified chemoradiation protocol for all HPV associated squamous cell carcinoma will certainly improve the quality of life of such patients.
ABSTRACT
This case control study had been carried out to evaluate antidiabetic and antioxidant activities of Tinospora cordifolia (T. cordifolia; family: Menispermaceae) against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes. Ethanolic extract of T. cordifolia stem extract and standard drug (glibenclamide) macerated with aqueous gum acacia (2%, w/v) suspension and fed orally to streptozotocin induced male adult diabetic rats of Charles Foster strain for 30 days. Biochemical parameters in normal, diabetic control, standard (600µg/kg bw p.o.) and treated (500 mg/kg bw p.o.) animals group were determined and compared. Treatment of streptozotocin induced diabetic rats with ethanolic extract caused significant (p<0.001) reduction in blood glucose, total cholesterol, triglyceride, phospholipids, free fatty acid, lipid peroxide and significant increased (p<0.001) post heparin lipolytic activity. Furthermore, the stem extract (100-400 µg) when tested for its antioxidant activity in vitro, shown significant (p<0.001) inhibit the generation of super oxide anions in enzymic system a, in enzymic system b, non enzymic system and hydroxyl radicals in enzymic system and non-enzymic system. The results of the present study demonstrated antidiabetic antidyslipidemic and anti oxidant activities of T. cordifolia stem extract which could help in prevention of diabetic- dyslipidemia and related complications.
ABSTRACT
Free radicals are responsible for causing many chronic and degenerative diseases. Antioxidants are substances capable of scavenging free radicals and preventing cell damage. In this context, antioxidant activity of alcoholic extracts from leaves of Anacardium occidentale and Myracrodruon urundeuva was evaluated by 2,2-diphenyl-1-picrylhydrazyl DPPH and 2,2'-azinobis-(3-ethyl-benzothiazolin6-sulfonic acid) ABTS methods. Phenolic content and phytochemical analysis were performed for each species. Results showed that both species exhibited free radical scavenging activity. These results are directly related to high phenolic content found in the extracts. M. urundeuva showed antioxidant activity similar to butylhydroxytoluene (BHT) and could be considered a promising plant source of natural antioxidant.
Os radicais livres são responsáveis por causar muitas doenças crônicas e degenerativas. Os antioxidantes são substâncias capazes de eliminar radicais livres e impedi-los de causar danos celulares. Neste contexto, a atividade antioxidante dos extratos alcoólicos das folhas de Anacardium occidentale e Myracrodruon urundeuva foi avaliada pelos métodos de 2,2- difenil-1-picrilhidrazil (DPPH) e 2,2'-azinobis-(3-etil-benzothiazolin-6-sulfónico ácido) (ABTS). O conteúdo fenólico e análise fitoquímica dos extratos também foram avaliados. As duas espécies exibiram atividade sequestradora de radicais livres. Estes resultados estão relacionados com alto teor de compostos fenólicos encontrados nos extratos. M. urundeuva mostrou atividade antioxidante semelhante ao butilhidroxitolueno (BHT), se tornando uma fonte promissora de antioxidante natural.
Subject(s)
Phenolic Compounds , Anacardium , Antioxidants/analysis , Free RadicalsABSTRACT
ABSTRACT: The objective of this study was to assess the effects of including grape pomace in the diet of pigs on pork quality and oxidative stability of body fat enriched with omega-3 fatty acids. Four treatments were compared: T1) Control diet based on corn and soybean meal; T2) Diet with inclusion of 3% of a canola (50%) and flaxseed (50%) oil blend; T3) Diet with inclusion of 3% of the oil blend and sequential levels of 3 and 5% of grape pomace; T4) Diet with inclusion of 3% of the oil blend and sequential levels of 6 and 10% of grape pomace. Inclusion of grape pomace in the diet led to an increase (P<0.10) of a* value and color saturation index of meat. The omega-3 and polyunsaturated fatty acids (PUFA) content of backfat were increased (P>0.10) with dietary inclusion of oils blend. Neither the inclusion of the oil blend, nor the grape pomace had any effect (P>0.10) on the production of thiobarbituric acid reactive substances (TBARS) in the loin samples, despite the higher PUFA content in the fat of pigs fed the oil blend. Antioxidant effect of grape pomace was not possible to prove when measured by TBARS, but the increased redness of the pork from pigs fed with this ingredient suggested a possible antioxidant effect of grape pomace.
RESUMO: Este trabalho teve como objetivo avaliar a inclusão do bagaço de uva na dieta de suínos sobre a qualidade da carne e, a estabilidade oxidativa da gordura corporal enriquecida com ácidos graxos ômega-3. Foram comparados quatro tratamentos: T1 - Dieta controle baseada em milho e farelo de soja; T2 - Dieta com inclusão de 3% de uma mistura de óleos de canola (50%) e de semente de linho (50%); T3 - Dieta com inclusão de 3% da mistura de óleos e níveis sequenciais de 3 e 5% de bagaço de uva e; T4 - Dieta com inclusão de 3% da mistura de óleos e níveis sequenciais de 6 e 10% de bagaço de uva. A inclusão do bagaço de uva na dieta resultou no aumento (P<0,10) do valor de a* e índice de saturação da cor da carne. O conteúdo de ômega-3 e ácidos graxos poli-insaturados (PUFA) do toucinho aumentaram (P<0,10) em função da inclusão da mistura de óleos na dieta. A mistura de óleos e o bagaço de uva não afetaram a produção de substâncias reativas ao ácido tiobarbitúrico (TBARS) nas amostras de lombo, apesar do maior conteúdo de PUFA na gordura dos suínos que receberam a mistura de óleos na dieta. Não foi possível provar efeito antioxidante do bagaço de uva na carne através da determinação dos valores de TBARS. Porém, a cor vermelha mais intensa na carne dos suínos alimentados com este ingrediente sugere um possível efeito antioxidante do bagaço de uva.
ABSTRACT
Diabetes mellitus can damage the eyes, kidneys, nerves and heart. Microvascular and macrovascular disorders are the leading causes of morbidity and mortality in diabetic patients. Hyperglycemia can increase the indicators of lipid peroxidation and oxidative stress in which free radicals have the main role in the pathogenesis of these complications. Therefore, antioxidants which combat oxidative stress should be able to prevent and repair free radicals induced damages. Although free radicals contribute to kidney damage, atherosclerosis, diabetes, heart disease, nephrotoxicity and hepatotoxicity; however, clinical trials do not uniquely confirm a substantial impact on diabetic damage. It seems that antioxidants in vegetables, fruits and grains help preventing diabetes complications; however, there is little evidence that taking single antioxidants such as vitamin E or vitamin C protect these complications. The findings about combination antioxidants are also complicated and not entirely clear. In this review paper we tried to present the role of oxidative stress on micro-vascular complications of type 2 diabetes mellitus. Other objective of this paper is to review the new findings about the role of various antioxidants on prevention and treatment of diabetes mellitus as well as its complications including retinopathy, nephropathy and neuropathy.
ABSTRACT
Diabetes mellitus can damage the eyes, kidneys, nerves and heart. Microvascular and macrovascular disorders are the leading causes of morbidity and mortality in diabetic patients. Hyperglycemia can increase the indicators of lipid peroxidation and oxidative stress in which free radicals have the main role in the pathogenesis of these complications. Therefore, antioxidants which combat oxidative stress should be able to prevent and repair free radicals induced damages. Although free radicals contribute to kidney damage, atherosclerosis, diabetes, heart disease, nephrotoxicity and hepatotoxicity; however, clinical trials do not uniquely confirm a substantial impact on diabetic damage. It seems that antioxidants in vegetables, fruits and grains help preventing diabetes complications; however, there is little evidence that taking single antioxidants such as vitamin E or vitamin C protect these complications. The findings about combination antioxidants are also complicated and not entirely clear. In this review paper we tried to present the role of oxidative stress on micro-vascular complications of type 2 diabetes mellitus. Other objective of this paper is to review the new findings about the role of various antioxidants on prevention and treatment of diabetes mellitus as well as its complications including retinopathy, nephropathy and neuropathy.
ABSTRACT
O trabalho teve como objetivo desenvolver e caracterizar embalagens ativas flexíveis formuladas pela incorporação de polpas de frutas tropicais a uma matriz polimérica de amido de mandioca plastificada com glicerol, avaliando as propriedades mecânicas, de barreira e a eficácia antioxidante destas embalagens durante o armazenamento. As embalagens foram produzidas por casting, com concentrações fixas de amido de mandioca (4,5%) e glicerol (1,0%), e concentrações de polpa de manga, acerola e seriguela entre 5 e 20%. Foram caracterizadas as propriedades de barreira (espessura, umidade, sólidos totais, atividade de água e solubilidade) e propriedades mecânicas dos filmes. A ação antioxidante dos aditivos incorporados foi avaliada através do armazenamento do azeite de dendê embalado com os filmes contendo os aditivos naturais, monitorando a sua oxidação por 40 dias, sob condições de oxidação acelerada (63%UR/30°C). A adição das polpas de frutas aos filmes promoveu um aumento da resistência mecânica. Os filmes com as polpas incorporadas desempenharam efeito antioxidante sobre o azeite de dendê durante os 40 dias de armazenamento, podendo ser aplicados para o controle da oxidação deste produto.
This research aimed to develop and characterize flexible active packages formulated by the incorporation of pulps from tropical fruits to a polymeric matrix of manioc starch, plasticized with glycerol. The mechanical properties, the barriers and the antioxidant efficacy of these packages were evaluated during storing. The packages were produced by casting, with fixed concentrations of manioc starch (4.5%) and glycerol (1.0%), and variable concentrations of mango, acerola and seriguela pulps between 5 and 20%. The barrier properties (width, humidity, total solids, water activity and solubility) and the mechanical properties of the films were evaluated. The antioxidant action of the additives incorporated was evaluated through the storage of palm oil packed with the films containing the natural additives. Its oxidation was monitored for 40 days, under conditions of accelerated oxidation (63%UR/30ºC). The addition of fruit pulps to the films promoted an increase of the mechanical resistance. The films with the added pulps performed an antioxidant effect on the palm oil during the 40 days storage, which could be applied for the oxidation control of this product.
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Objective: To determine the extraction suitable conditions of total phenolic content (TPC) by heat-reflux system, antioxidant activities and HPLC characterization of the aqueous-ethanolic extracts of Jatropha dioica (J. dioica) (Dragon's blood), Flourensia cernua (F. cernua) (Tar bush), Eucalyptus camaldulensis (E. camaldulensis) (Eucalyptus) and Turnera diffusa (T. diffusa) (Damiana). Methods: TPC was evaluated by the well-known colorimetric assay using Folin-Ciocalteu reagent. The antioxidant activities were assayed by three methods based on scavenging of DPPH, ABTS and by lipid oxidation inhibition. The chemical composition of the extracts obtained was subject to HPLC analysis. Results: TPC in the plant extracts ranged from 2.3 to 14.12 mg gallic acid equivalents/g for J. dioica and E. camaldulensis, respectively. The plant extracts of F. cernua, E. camaldulensis and T. diffusa showed similar strong antioxidant activities on scavenging of DPPH and lipid oxidation inhibition. In contrast, J. dioica extracts had lowest potential antioxidant in three assays used. HPLC assay showed the presence of several phenolic compounds in the extracts used. Conclusions: The results obtained suggest that F. cernua, E. camaldulensis and T. diffusa are potential sources to obtain bioactive phenolic compounds with high antioxidant properties which can be used in the factories as antioxidant agents or for treatments in diseases.
ABSTRACT
OBJECTIVE@#To determine the extraction suitable conditions of total phenolic content (TPC) by heat-reflux system, antioxidant activities and HPLC characterization of the aqueous-ethanolic extracts of Jatropha dioica (J. dioica) (Dragon's blood), Flourensia cernua (F. cernua) (Tar bush), Eucalyptus camaldulensis (E. camaldulensis) (Eucalyptus) and Turnera diffusa (T. diffusa) (Damiana).@*METHODS@#TPC was evaluated by the well-known colorimetric assay using Folin-Ciocalteu reagent. The antioxidant activities were assayed by three methods based on scavenging of DPPH, ABTS and by lipid oxidation inhibition. The chemical composition of the extracts obtained was subject to HPLC analysis.@*RESULTS@#TPC in the plant extracts ranged from 2.3 to 14.12 mg gallic acid equivalents/g for J. dioica and E. camaldulensis, respectively. The plant extracts of F. cernua, E. camaldulensis and T. diffusa showed similar strong antioxidant activities on scavenging of DPPH and lipid oxidation inhibition. In contrast, J. dioica extracts had lowest potential antioxidant in three assays used. HPLC assay showed the presence of several phenolic compounds in the extracts used.@*CONCLUSIONS@#The results obtained suggest that F. cernua, E. camaldulensis and T. diffusa are potential sources to obtain bioactive phenolic compounds with high antioxidant properties which can be used in the factories as antioxidant agents or for treatments in diseases.
ABSTRACT
Introducción: la especie Kalanchoe daigremontiana Raym.-Hamet. & H. es una planta que presenta muy poca información sobre estudios de capacidad antioxidante, a pesar de su amplio uso en la medicina tradicional, lo cual presupone una fuente potencial de sustancias bioactivas con propiedades antioxidantes. Objetivo: evaluar el potencial antioxidante de los extractos de hojas y flores de Kalanchoe daigremontiana. Métodos: los extractos de hojas y flores se obtuvieron en metanol acidulado (HCl 10 % v/v) y su capacidad antioxidante se determinó sobre la base de los métodos del radical DPPH, del catión-radical ABTS y contenido de antocianinas totales. Resultados: los extractos, tanto de hojas como flores, mostraron un potencial antioxidante promisorio (EC50= 4,2-4,4 g extracto/mmol DPPH; 1,71-2,05 mmol Trolox/kg extracto). Adicionalmente se determinó la presencia en las flores de las antocianinas delfinidina, cianidina y pelargonidina. Conclusiones: la Kalanchoe drageimontiana presentó efecto antioxidante significativo tanto en las hojas como en las flores, comparable con el mostrado por el ácido ascórbico. Se identificó de modo tentativo la presencia de delfinidina 3-O-glucósido, cianidina 3-O-glucósido y pelargonidina 3-O-glucósido en el extracto flores; por tanto la especie bajo estudio puede ser aprovechada como fuente de sustancias bioactivas para su aplicación como aditivos en la industria de alimentos, cosmética o farmacéutica.
Introduction: little information is available on the antioxidant capacity of the species Kalanchoe daigremontiana Raym.-Hamet. & H. However, its widespread use in traditional medicine points to its potential as a source of bioactive substances with antioxidant properties. Objective: evaluate the antioxidant potential of extracts from Kalanchoe daigremontiana leaves and flowers. Methods: leaf and flower extracts were obtained in acidulated methanol (HCl 10 % v/v), and their antioxidant capacity was gauged by DPPH and ABTS radical cation assay and total anthocyanin content determination. Results: both leaf and flower extracts displayed promising antioxidant potential (EC50= 4.2-4.4 g extract/mmol DPPH; 1.71-2.05 mmol Trolox/kg extract). Determination was also made of the presence of anthocyanins delphinidin, cyanidin and pelargonidin in the flowers. Conclusions: Kalanchoe drageimontiana leaves and flowers displayed significant antioxidant capacity, comparable to that of ascorbic acid. The presence of delphinidin-3-O-glucoside, cyanidin-3-O-glucoside and pelargonidin-3-O-glucoside was tentatively identified in the flower extract. Therefore, the study species may be used as a source of bioactive substances for use as additives in the food, cosmetic or pharmaceutical industry.
ABSTRACT
Calcium alginate beads containing pomegranate peels' polyphenol extract were encapsulated by ionic gelation method. The effects of various formulation factors (sodium alginate concentration, calcium chloride concentration, calcium chloride exposure time, gelling bath time maintaining, and extract concentration) on the efficiency of extract loading were investigated. The formulation containing an extract of 1 g pomegranate peels in 100 mL distilled water encapsulated with 3 % of sodium alginate cured in 0.05 M calcium chloride for 20 minutes and kept in a gelling bath for 15 minutes was chosen as the best formula regarding the loading efficiency. These optimized conditions allowed the encapsulation of 43.90% of total extracted polyphenols and 46.34 % of total extracted proanthocyanidins. Microencapsulation of pomegranate peels' extract in calcium alginate beads is a promising technique for pharmaceutical and food supplementation with natural antioxidants.
Pérolas de alginato de cálcio, contendo polifenóis de extrato de casca de romã, foram encapsuladas pelo método de gelificação iônica. Os efeitos de vários fatores de formulação (concentração de alginato de sódio, concentração de cloreto de cálcio, cloreto de cálcio, o tempo de exposição, o tempo de manutenção do banho de gelificação e a concentração do extrato) sobre a eficiência de carga do extrato foram investigados. A formulação que contém 1 g extrato de casca de romã em 100 mL de água destilada, encapsulado com 3% de alginato de sódio curada em 0,05 M de cloreto de cálcio durante 20 minutos e mantido em banho de gelificação por 15 min foi escolhida como a melhor em relação à eficiência de carga. Estas condições otimizadas permitem o encapsulamento de 43,90% do total de polifenóis extraídos e de 46,34% do total de proantocianidinas extraídas. A microencapsulação de extrato de cascas de romã em esferas de alginato de cálcio é uma técnica promissora para a suplementação farmacêutica e de alimentos com antioxidantes naturais.