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1.
Int J Biol Macromol ; 228: 23-39, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36565824

RESUMEN

Hops' (Humulus lupulus L.) phytochemicals are well known for their bioactivity. In the present study, the functional properties of hop extract rich in ß-acids, as potassium-salts structures (KBA), were investigated to develop a sustainable active food packaging. Polylactic acid (PLA)-based sheets were incorporated with increasing concentrations of hop extract (0.1-5 % w/w in terms of KBA) and characterized through performance and bioactive properties. KBA-added sheets presented decreased crystallinity and affected mechanical and thermal properties, especially with higher KBA amounts. The sheets' surface hydrophobicity gradually decreased by KBA-extract addition, while the water vapor permeability was not affected. A Fickian diffuse behavior and a better fit to application in fatty foods were observed during release tests. UV-blocking and antioxidant properties were improved by KBA incorporation. Furthermore, results from antibacterial assays revealed great susceptibility of Staphylococcus aureus and Listeria monocytogenes towards sheets added with 5 % of KBA. Moreover, the atomic force microscopy (AFM) observations revealed that KBA led to strong effects on the cell membranes of both bacteria, including disruption of membrane integrity and cell death. Therefore, this study is a sign of great prospects of hop ß-acids use, as KBA compound, in the production of sustainable active packaging for safe food shelf-life extension.


Asunto(s)
Embalaje de Alimentos , Humulus , Embalaje de Alimentos/métodos , Humulus/química , Antibacterianos/farmacología , Poliésteres , Ácidos
2.
Nat Prod Res ; 36(5): 1405-1408, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33641558

RESUMEN

Polyphenols, condensed tannins, total flavonoids, total carotenoids, lycopene and ascorbic acid were determined besides verifying antioxidant capacity of peel, pulp and desserts (with and without sugar) of red guava (Psidium guajava L.) as well as the effects of lycopene on cytotoxicity, cell cycle and apoptosis on breast cancer cell line MCF-7. Guava peel contains 90% of the total ascorbic acid and heat treatment does not modify bioactive compounds content and antioxidant capacity. Sugar addition decreased guava pulp functional capacity. After heat treatment, lycopene content was stable, but sugar addition reduced its concentration by 57%. Lycopene (10 µM) extracted from guava and standard presented the same cytotoxic effect on MCF-7 cells. Lycopene influenced over G2-M transition check-point of the cell cycle and increased apoptotic cells percentages compared to untreated cells. The consumption of in natura guava, especially with peel can be considered an important source of bioactive compounds.


Asunto(s)
Neoplasias de la Mama , Psidium , Antioxidantes/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Carotenoides/farmacología , Femenino , Humanos , Licopeno/farmacología
3.
Food Res Int ; 156: 111160, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35651026

RESUMEN

Aiming to attend to consumers' increasing demand for synthetic additives-free food products (stimulated by personal preferences or health concerns), the food industry has been trying to introduce natural bioactive compounds as food preservatives. In this respect, the development of active food packaging incorporated with natural compounds could be of great interest. However, this scenario still has some particularities that can hinder its application in the food industry, such as relatively reduced stability and, in some cases, undesirable sensorial properties. Cyclodextrins showed up as an option to circumvent these drawbacks by forming inclusion complexes that can protect the active compounds and perform their controlled release for contact with packaged food. For industrial manufacturing of active packages based on naturally occurring bioactive compounds, inclusion complexation can be considered one of the most promising alternatives. Therefore, this review summarizes the potential of nanotechnology in active food packaging by applying cyclodextrins as a carrier for natural active compounds, which can be provided by conventional sources and alternatively (and cost-effectively) agro-food by-products. The present study will benefit prospects for exploring cyclodextrins in active food packaging, which industrial application, without a doubt, will increase in the coming years.


Asunto(s)
Ciclodextrinas , Aceites Volátiles , Embalaje de Alimentos/métodos , Conservantes de Alimentos , Aceites Volátiles/análisis , Extractos Vegetales , Plantas
4.
RSC Adv ; 9(10): 5620-5627, 2019 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35515895

RESUMEN

Phosphorus (P) is a nutrient necessary for agricultural production and a potential originator for eutrophication in water bodies, resulting in qualitative changes; it may also affect the aquatic ecosystem and human health. In addition, as a finite resource, the importance of studying strategies to remove it from water is evident, thus making possible its recycling. Many studies have used powdered materials, including biochars, for P water decontamination; however, the difficulty of separating and collecting these materials from water after adsorption may be difficult. Therefore, using hybrid materials in which the fine particles (powder) are impregnated into larger, solid particles by means of a polymeric host can facilitate collection and reuse after P adsorption. In this context, this study aimed the synthesis and characterization of a new hybrid film formed by the biopolymer cellulose acetate (CA) and biochar (FAC-B) for P adsorption in aqueous solution. We obtained biochar from the pyrolysis of carrot residue (Daucus carota L.) and doped it with magnesium. As a biodegradable polymer and the most abundant natural polysaccharide in the environment, using CA as a biochar support material is an environmentally friendly alternative. We prepared the CA film with the casting method, and the biochar was inserted into the filmogenic solution in the same amount as the CA. The film was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), molecular absorption spectroscopy in the infrared region with an attenuated total reflectance (FTIR/ATR) accessory, and X-ray Photoelectron Spectroscopy (XPS). We evaluated the thickness, weight, density, H2O uptake and H2O solubility of the produced FAC-B. The maximum adsorption capacity of P by FAC-B was 21.57 mg g-1, in agreement with the Langmuir isotherm model. The adsorption value suggests that the film has the potential to be used as an efficient P adsorbent in water.

5.
Rev. Inst. Adolfo Lutz (Online) ; 81: e39118, mar.1, 2022. tab
Artículo en Portugués | LILACS, CONASS, Coleciona SUS (Brasil), SES-SP, SESSP-ACVSES, SES SP - Instituto Adolfo Lutz, SES-SP, SESSP-IALACERVO | ID: biblio-1416460

RESUMEN

Este estudo objetivou analisar a conformidade de 56 rótulos de produtos alimentícios divididos em 14 categorias em relação às legislações gerais e específicas de rotulagem de alimentos vigentes até o momento de sua publicação, bem como apresentar abordagens com relação à necessidade da constante melhoria e aperfeiçoamento da legislação. Constatou-se um total de 158 não conformidades e que 55,3% dos produtos avaliados apresentavam pelo menos uma não conformidade em sua rotulagem. Biscoitos e produtos artesanais foram as categorias que mais apresentaram rótulos com pelo menos uma não conformidade. Entre as informações obrigatórias, as referentes ao lote, à data de fabricação, ao prazo de validade e à conservação foram as mais recorrentes entre as não conformidades. Verificou-se também que algumas expressões como "produto caseiro", "vegano", "vegetariano", "base vegetal", entre outras, requerem melhor regulamentação ou legislação específica, portanto, não puderam ser avaliadas em relação à conformidade. Os motivos para tal cenário podem ser a aplicação incorreta da legislação e o uso de estratégias de marketing com o objetivo de atender a desejos e expectativas dos consumidores. Portanto, faz-se necessária uma intensificação da fiscalização, assim como maior celeridade na regulamentação de alegações específicas por parte dos órgãos responsáveis (AU).


This study aimed to evaluate the suitability of the labeling of 56 industrialized and packaged food products in the absence of the consumer, divided into 14 categories, before general and specific legislations on food labeling was in force at the time of its publication, as well as to present an approach regarding the need for constant improvement of legislation. It was found that 55.3% of the products presented at least one non-compliance in their labeling, and that there were a total of 159 non-compliances. Cookies and products with artisanal claims were the categories that most often presented products with at least one non-conformity. Among the mandatory information, batch, production date, expiration date, and conservation conditions were the ones that most presented non-conformities. It was also found that some claims, such as vegan, vegetarian, homemade, and plant-based, among others, lack of specific legislation, and therefore could not be assessed whether it was in compliance. This scenario shows misapplication of current legislation by food industry, as well as marketing strategies aiming to meet consumer''s seek. Thus, it is necessary to intensify inspection and also speed up the requirement for specific claims for the responsible agencies, mainly those related to health issues (AU).


Asunto(s)
Seguridad de Productos para el Consumidor , Etiquetado de Alimentos , Legislación Alimentaria
6.
Mater Sci Eng C Mater Biol Appl ; 78: 932-941, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28576069

RESUMEN

The production of biodegradable plastic materials using natural resources has aroused increased attention due to environmental concerns. This study aimed to manufacture novel, commercially feasible, biodegradable sheets by flat die extrusion-calendering process produced with thermoplastic starch/plasticized cellulose acetate (TPS/PCA) and thermoplastic starch/plasticized cellulose acetate/poly (butylene adipate-co-terephthalate) (TPS/PCA/PBAT) blends, and to investigate the effects of composition and processing conditions, morphological characteristics, and thermal properties. The results showed that TPS/PCA and TPS/PCA/PBAT biodegradable sheets properties were highly dependent upon both composition and processing temperature. The morphological characteristics and thermal properties of the sheets demonstrated the good compatibility between TPS and PCA in TPS/PCA blends, mainly at higher processing temperatures, whereas TPS/PCA/PBAT sheets present a heterogeneous structure due to the poor compatibility between the components. TPS/PCA biodegradable sheets presented suitable processability and handleability characteristics that allow them to be considered as a novel eco-friendly, economically feasible alternative to conventional plastic materials.


Asunto(s)
Almidón/química , Celulosa/análogos & derivados , Poliésteres , Temperatura
7.
Plant Physiol Biochem ; 44(7-9): 467-73, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17023171

RESUMEN

Acid phosphatase activity (orthophosphoric-monoester phosphohydrolase, EC 3.1.3.2) increased during the first 24 h of maize (Zea mays) seed germination. The enzyme displayed a pH optimum of 4.5-5.5. Catalytic activity in vitro displayed a linear time course (60 min) and reached its half maximum value at 0.47 mM p-nitrophenyl phosphate (pNPP). Phosphatase activity towards phosphoamino acids was greatest for phosphotyrosine. The phosphatase activity was strongly inhibited by ammonium molybdate, vanadate and NaF and did not require divalent cations for the catalysis. The temperature optimum for pNPP hydrolysis was 37 degrees C. Under the same conditions, no enzyme activity was detected with phytic acid as substrate. Western blotting of total homogenates during seed germination revealed proteins/polypeptides that were phosphorylated on tyrosine residues; a protein of approximately 14 kDa is potentially a major biological substrate for the phosphatase activity. The results presented in this study suggest that the acid phosphatase characterized under the tested conditions is a member of the phosphotyrosine phosphatase family.


Asunto(s)
Fosfatasa Ácida/metabolismo , Germinación/fisiología , Proteínas de Plantas/metabolismo , Semillas/enzimología , Zea mays/enzimología , Fosfatasa Ácida/antagonistas & inhibidores , Cationes Bivalentes/farmacología , Activación Enzimática , Germinación/efectos de los fármacos , Concentración de Iones de Hidrógeno , Cinética , Molibdeno/farmacología , Nitrofenoles/metabolismo , Compuestos Organofosforados/metabolismo , Fosforilación , Ácido Fítico , Semillas/efectos de los fármacos , Fluoruro de Sodio/farmacología , Temperatura , Tirosina/metabolismo , Vanadatos/farmacología , Zea mays/efectos de los fármacos
8.
Insect Biochem Mol Biol ; 29(3): 215-23, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10319435

RESUMEN

Protein kinase casein kinase II (CK II) activity was assayed during Rhodnius prolixus embryogenesis. Vitellin (VT) is the main endogenous substrate during the whole development. It is maximally phosphorylated at the third day of embryogenesis by CK II and then its phosphorylation decreases to a basal level by the time of first instar eclosion. When dephosphorylated casein was used as an exogenous substrate a different profile of enzyme activity was obtained. CK II activity increases on day 1 after fertilization and reaches a plateau on day 7 and its activity remains elevated until eclosion. Extracts obtained from oocytes or from 3-day old eggs were fractionate through gel filtration chromatography. CK II activity was assayed in each fraction and the enzyme obtained from the 3-day old eggs was shown to be three times more active than that obtained from oocytes, although the amount of enzyme present in the fractions was the same. These enriched CK II fractions were assayed against different effectors, such as: cAMP, H-8, H-89, calphostin C, sphingosine, polylysine and heparin. Heparin was the most effective one. When CK II activity was assayed in non-fertilized eggs, no activation of the enzyme was observed when compared to fertilized eggs. These data indicate that CK II is activated in a fertilization dependent process. The decrease in CK II activity against VT coincides with the beginning of VT proteolysis processing suggesting a possible relationship between protein phosphorylation and yolk degradation.


Asunto(s)
Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas/metabolismo , Rhodnius/metabolismo , Animales , Western Blotting , Quinasa de la Caseína II , Caseínas/metabolismo , Fraccionamiento Celular , Cromatografía en Gel/métodos , Oocitos/enzimología , Óvulo , Fosforilación , Rhodnius/embriología
9.
Nat Prod Res ; 25(11): 1037-46, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21500093

RESUMEN

The propolis of Scaptotrigona aff. postica is popularly used in Maranhão State, Brazil, for treating wounds and respiratory illnesses. Nevertheless, little is known about the chemical composition of this propolis and the adverse effects of its use. Hence, this study is a pharmacognostic characterisation of the propolis hydroalcoholic extract (PHE) from S. aff. postica. The methodology consisted of an evaluation of the sensory and chemical parameters. Chemical analysis of PHE indicated high concentrations of phenolic and triterpens substances, and the absence of steroids. Additionally, we evaluated the acute toxicity of propolis using 48 Swiss male and female mice. The animals received single doses of PHE (1000, 2000 or 4000 mg kg⁻¹) orally and were observed for 14 days. After this period, the mice were sacrificed and the blood was used for biochemical and haematological evaluation. PHE did not induce any death, and the acute treatment significantly reduced serum concentrations of alanine aminotransferase and alkaline phosphatase. The resultant data indicate that PHE from S. aff. postica has low toxicity when used orally, even in high doses.


Asunto(s)
Abejas/química , Própolis/química , Pruebas de Toxicidad Aguda/métodos , Alanina Transaminasa/sangre , Alanina Transaminasa/metabolismo , Fosfatasa Alcalina/sangre , Fosfatasa Alcalina/metabolismo , Animales , Activación Enzimática/efectos de los fármacos , Femenino , Masculino , Ratones
10.
Arq. bras. med. vet. zootec ; 67(2): 535-546, Mar-Apr/2015. tab
Artículo en Inglés | LILACS, VETINDEX | ID: lil-747057

RESUMEN

The aim of this work was to evaluate the effects of adding different levels of glycerin in the feeding on the lipid profile and cholesterol of the meat of finishing pigs. The experiment was arranged in a completely randomized design (CRD) with factorial 5x2, being five levels of glycerin in the diet and two genders. Sixty (60) swine of the Topigs genetics (30 barrows and 30 gilts) were used; they presented initial average weight of 79.3+4.0kg and were finished with the weight of 106.2+4.5kg. The levels of glycerin utilized were 0, 50, 100, 150 and 200g/kg in the natural matter. The analyses of lipid and cholesterol profile were conducted in the muscles longissimus dorsi (loin) andsemimembranosus (ham) on the left side of the carcasses. Interaction occurred between the levels of crude glycerin in the diet and the sexual category for the profile of fatty acids and cholesterol. On the loin the meat of the barrows presented higher means of C16:0, C16:1, C20:3ω3, C18:1ω9c, Total of saturated (SFA) and monounsaturated (MUFA) fatty acids. On the ham, increased means were found for the fatty acids C18:1ω9c, MUFA, activity of ∆9-desaturaseC18 and ElongaseC16-18 in barrows. The sows' meat presented higher proportions of polyunsaturated fatty acids and of the series ω6 for both the cuts. The amount of cholesterol in the sows' meat presented increase according to the level of glycerin in the meat. The barrows' meat presented indices of atherogenicity greater than the gilts. The levels of glycerin altered the lipid profile and cholesterol content according to the sexual category, promoting a distinct effect on the loin and ham.(AU)


O objetivo deste trabalho foi avaliar os efeitos do fornecimento de diferentes níveis de glicerina na alimentação sobre o perfil lipídico e colesterol da carne de suínos em terminação. O delineamento experimental foi organizado inteiramente ao acaso (DIC), com fatorial 5x2, sendo: cinco níveis de glicerina na dieta e dois sexos. Foram utilizados 60 suínos da genética Topigs (30 machos castrados e 30 fêmeas), apresentando peso médio inicial de 79,3+4,0kg, e foram terminados com peso de 106,2+4,5kg. Os níveis de glicerina utilizados foram de 0, 50, 100, 150 e 200g/kg na matéria natural. As análises de perfil lipídico e de colesterol foram realizadas nos músculos longissimus dorsi (lombo) e semimembranosus (pernil) do lado esquerdo das carcaças. Ocorreu interação entre os níveis de glicerina bruta na dieta e a categoria sexual para o perfil de ácidos graxos e colesterol. A carne dos machos castrados apresentou no lombo maiores médias de C16:0, C16:1, C20:3ω3, C18:1ω9c, Total de ácidos graxos Saturados (SFA) e Monoinsaturados (MUFA). No pernil, maiores médias foram verificadas para os ácidos graxos C18:1ω9c, MUFA, atividade da ∆9-desaturaseC18 e ElongaseC16-C18 em machos castrados. A carne das fêmeas suínas apresentou maiores proporções de ácidos graxos poli-insaturados e da série ω6 para ambos os cortes. A quantidade de colesterol na carne das fêmeas suínas apresentou aumento em função do nível de glicerina na dieta. A carne dos machos castrados apresentou maiores índices de aterogenicidade que das fêmeas. Os níveis de glicerina alteraram o perfil lipídico e teor de colesterol em função da categoria sexual, promovendo efeito diferenciado no lombo e pernil.(AU)


Asunto(s)
Animales , Porcinos , Colesterol , Glicerol/administración & dosificación , Lípidos , Alimentación Animal , Carne/análisis
11.
Arq. bras. med. vet. zootec ; 64(1): 127-136, Feb. 2012. tab
Artículo en Portugués | LILACS | ID: lil-617939

RESUMEN

Avaliou-se o efeito da inclusão de fitase em dietas com proteína bruta (PB) e fósforo disponível (Pd) reduzidos sobre o desempenho, rendimento de carcaça e cortes e quantidade de poluentes na cama de frangos dos 22 aos 42 dias de idade. Foram utilizados 1200 pintos aos 21 dias, média de peso inicial de 646±8g, distribuídos em blocos ao acaso em esquema fatorial 3x3+1 (três porcentagens de Pd - 0,2, 0,3 e 0,4 por cento - e três de PB - 14, 16 e 18 por cento - e um tratamento adicional, padrão) em seis repetições de 20 aves cada. A fitase (500FTU/kg) foi adicionada nas dietas com fósforo reduzido (0,2 e 0,3 por cento). Aos 42 dias as aves foram abatidas e amostras das camas foram encaminhadas para análise. Em dietas com reduzido teor de PB, melhor desempenho e rendimento de carcaça e menor quantidade de fósforo, cálcio, potássio e zinco nas camas foram obtidos com 0,3 por cento Pd+fitase. Menor quantidade de nitrogênio e potássio, porém com maior deposição de gordura abdominal e maior excreção de cobre, foram obtido com 14 por cento de PB. Comparadas ao controle, dietas com 14 por cento de PB e 0,3 por cento de Pd reduziram a excreção de fósforo em 34 por cento. Conclui-se que dietas com 14 por cento de PB e 0,3 por cento de Pd, suplementadas com fitase e aminoácidos cristalinos, podem ser utilizadas para frangos de corte dos 22 aos 42 dias.


The effect of the inclusion of phytase in reduced crude protein (CP) and available phosphorus (aP) diets on performance, carcass and cut yields and the amount of pollutant elements in the litter of broilers from 22 to 42 days of age was evaluated. One thousand and two hundred male broilers at 21 days of age, initial weight of 646±8g, were distributed in randomized block design in factorial scheme 3x3+1 (three levels of aP - 0.2, 0.3 and 0.4 percent - and three of CP - 14, 16 and 18 percent - and an additional treatment, standard) in six repetitions of 20 birds each. Phytase (500 FTU/kg) was added in reduced phosphorus (0.2 and 0.3 percent) diets. At 42 days of age, the birds were sacrificed and samples of the litters were sent to the laboratory for analysis. In reduced-CP diets, the best performance and carcass yield and lesser quantity of phosphorus, calcium, potassium and zinc in the litter was obtained with 0.3 percent aP + phytase diets. The minor quantity of nitrogen and potassium in the litter, with higher abdominal fat deposition and excretion of cupper were obtained with 14 percent CP diets. Compared to control, diets with 14 percent CP and 0.3 percent aP reduced the excretion of phosphorus in 34 percent. It was concluded that diets with 14 percent CP and 0.3 percent aP, supplemented with phytase and crystalline amino acids, can be used in broilers from 22 to 42 days old.

12.
Arq. bras. med. vet. zootec ; 63(6): 1519-1525, dez. 2011. tab
Artículo en Portugués | LILACS | ID: lil-608977

RESUMEN

Dois experimentos foram realizados para avaliar a influência de duas porcentagens de lisina associada à restrição alimentar sobre o desempenho e balanço de nitrogênio de suínos em terminação. No experimento I, foram utilizados 48 suínos machos castrados, com média de peso de 76,2±2,3kg, distribuídos em delineamento em blocos ao acaso, em esquema fatorial 2x2 (duas porcentagens de lisina total - normal ou com 30 por cento a mais - e duas formas de arraçoamento - à vontade ou com restrição). Com 28 dias, a porcentagem de inclusão de lisina não influenciou o ganho de peso, mas a porcentagem mais alta resultou em menor consumo e melhor conversão alimentar. A restrição alimentar diminuiu o ganho de peso sem afetar a conversão alimentar. No experimento II, 24 suínos machos castrados, com média de peso de 74,1±2,5kg, foram alojados em gaiolas de metabolismo para receber os mesmos tratamentos. Aos 14 dias de experimento, as dietas não influenciaram a absorção de nitrogênio e a ureia plasmática, porém a dieta ad libitum com a maior porcentagem de lisina reduziu a retenção de nitrogênio. Aos 28 dias, essa mesma dieta aumentou a concentração de ureia plasmática. Conclui-se que o aumento da lisina nas rações melhora o desempenho de suínos machos castrados em terminação, independentemente da forma de arraçoamento, e que a restrição alimentar, nesta fase, não é benéfica.


Two experiments were led to evaluate the influence of two percentages of lysine associated to feed restriction over performance and nitrogen balance of finishing barrows. In experiment I, 48 barrows were used, weighing 76.2±2.3kg, distributed in a randomized blocks design in factorial scheme 2x2 (two levels of total lysine - normal or added in 30 percent - and two feed programs - restricted or ad libitum). At 28 days, the levels of lysine did not influence weight gain, but the higher level provided lesser feed intake and better feed:gain. The feed restriction decreased the weight gain without affecting feed:gain. In Experiment II, 24 barrows, weighing 74.1±2.5kg, were put in metabolic cages to receive the same previously described treatments. At 14 days of the experiment, the diets did not influence the nitrogen absorption and the plasmatic urea, however, the ad libitum diet associated at the higher lysine level reduced nitrogen retention. At 28 days, this same diet increased the plasmatic urea concentration. It was concluded that the increase of lysine levels in diets improves performance in finishing barrows, regardless of the feed program, and feed restriction, in this phase, is not beneficial.

13.
Ciênc. rural ; 41(3): 537-543, mar. 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-579658

RESUMEN

A indústria de alimentos, buscando atender à crescente demanda dos consumidores, vem desenvolvendo embalagens ativas para proporcionar qualidade e segurança aos produtos acondicionados. Este trabalho objetivou desenvolver e avaliar a aplicação de filmes ativos aromatizados em contato com a massa de pastel. Os filmes foram preparados pelo método casting, adicionados de ácido sórbico e aroma de pizza e avaliados in vitro frente ao microrganismo Penicillium sp. Também foram estudadas suas propriedades mecânicas, migração de ácido sórbico, avaliação sensorial do produto e análise microbiológica in vivo. Os filmes ativos apresentaram atividade antimicrobiana tanto in vitro como no alimento. A caracterização mecânica mostrou que os filmes ativos aromatizados apresentaram valores de carga máxima na ruptura, inferiores ao filme controle e, durante a migração, a adição de aroma contribuiu para uma maior liberação do ácido sórbico. Além disso, as massas de pastel em contato com os filmes ativos aromatizados apresentaram melhores resultados sensoriais.


The food industry, trying to meet growing consumer demand, is developing active packaging to provide quality and safety for packed food. This research aimed to develop and evaluate the implementation of active flavored films in contact with pastry dough. The active films were evaluated for in vitro antimicrobial activity against Penicillium sp. The mechanical properties of the films, the sorbic acid migration, sensory and in vivo microbiological analyses were also tested. The active films showed better results for in vitro and in vivo microbiological analyses when compared with the film with the sorbic acid incorporated directly on the pastry dough. The incorporation of sorbic acid and flavor affected the mechanical properties of the active films compared to the control film. The flavor addition provided a larger migration of sorbic acid from the film to the pastry dough. Besides the pastry dough packed in the active films showed better sensory results.

14.
J Biol Chem ; 271(47): 30227-32, 1996 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-8939975

RESUMEN

A novel calcium-binding phosphoprotein was isolated from the oocytes of the blood-sucking bug Rhodnius prolixus. This protein exhibits an apparent molecular mass of 18 kDa on gel filtration, but migrates as an 8-kDa band on N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine/SDS-polyacrylamide gels. It has a high content of serine (24% of the total number of residues), and phosphoserine is the sole amino acid phosphorylated in vivo. A similar protein was partially purified from the hemolymph. It resembles the oocyte form of the protein in its NH2-terminal sequence and its ability to be taken up by growing ovaries. 45Ca binding to the oocyte phosphoprotein was determined after SDS-polyacrylamide gel electrophoresis followed by blotting on nitrocellulose membranes. Titration of Ca2+-binding sites shows a high capacity (approximately 50 mol/mol of protein), but a low affinity (K0.5 congruent with 10(-3) M). Based on these characteristics, we have named this protein Rhodnius calcium-binding phosphoprotein. It resembles phosvitin, a phosphoprotein present in the oocytes of nonmammalian vertebrates.


Asunto(s)
Calcio/metabolismo , Hemolinfa/metabolismo , Oocitos/metabolismo , Fosfoproteínas/aislamiento & purificación , Rhodnius/metabolismo , Secuencia de Aminoácidos , Animales , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Femenino , Datos de Secuencia Molecular , Ovario/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Radioisótopos de Fósforo , Unión Proteica
15.
Arq. bras. med. vet. zootec ; 60(3): 719-724, jun. 2008. graf, tab
Artículo en Portugués | LILACS | ID: lil-487920

RESUMEN

Verificou-se o efeito da inclusão de um complexo de ácidos orgânicos (AO) e diferentes níveis de fitase em dietas de leitões na creche. Foram utilizados 40 leitões desmamados (7,8±0,8kg), distribuídos em delineamento de blocos inteiramente ao acaso, com cinco tratamentos e quatro repetições, durante um período experimental de 28 dias. Os tratamentos foram: T1- ração basal com 500UF/kg (controle); T2- ração basal com 500UF/kg + 0,2 por cento do complexo de AO; T3- ração basal com 450UF/kg + 0,2 por cento do complexo de AO; T4- ração basal com 400UF/kg + 0,2 por cento do complexo de AO; e T5- ração basal com 350UF/kg + 0,2 por cento do complexo de AO. A adição de AO à ração que continha 500UF propiciou maior (P<0,05) ganho de peso médio diário em relação ao tratamento-controle. Com relação aos níveis de fitase em dietas que continham AO não foram observadas diferenças (P>0,05) no ganho de peso. Para o consumo de ração médio diário, observou-se uma regressão quadrática (P<0,05), sendo o nível de 411UF o que propiciou o menor consumo de ração. O nível de 500UF + AO resultou em maior porcentagem de fezes normais em relação ao grupo-controle durante as duas últimas semanas do período experimental. Conclui-se que há efeito positivo da adição do complexo de ácidos orgânicos quando se suplementa fitase nas dietas de leitões na fase de creche dos oito aos 20kg.


The effect of inclusion of organic acids complex (OAC) and different levels of phytase in piglet diets were evaluated. Forty weaned piglets (7.8±0.8kg) were allotted in a completely randomized block design with five treatments and four repetitions, during an experimental period of 28 days. The treatments were: T1-basal diet with 500 phytase unit/kg (control); T2-basal diet with 500PU/kg + 0.2 percent of OAC; T3-basal diet with 450PU/kg + 0.2 percent of OAC; T4-basal diet with 400PU/kg + 0.2 percent of OAC; and T5-basal diet with 350PU/kg + 0.2 percent complex of OA. The addition of OAC at the 500PU diet increased (P<0.05) daily average gain compared to the control treatment. Comparing the phytase levels in diets containing OAC, it was not observed difference (P>0.05) in the weight gain. For the daily average feed intake, it was observed a quadratic effect (P<0.05), and the 411PU level caused lesser feed intake. The level of 500PU + OAC resulted in higher percentage of hard feces compared to the control group during the two last weeks of the experimental period. It was concluded that the effect of the OAC resulted positive when phytase was supplemented to the diets of piglets from eight to 20kg.


Asunto(s)
Animales , /efectos adversos , Ácidos Orgánicos/efectos adversos , Dieta , Diarrea/epidemiología , Porcinos
16.
Arq. bras. med. vet. zootec ; 59(5): 1270-1277, out. 2007. ilus, tab
Artículo en Portugués | LILACS | ID: lil-471212

RESUMEN

Avaliaram-se o desempenho e as características morfológicas e morfométricas do intestino delgado de 210 leitões, desmamados aos 15 dias de idade, com peso médio inicial 4,04±0,66kg, em dois períodos experimentais (15-30 e 15-36 dias de idade). O delineamento experimental foi em blocos ao acaso, com sete tratamentos (T1: ração-controle sem adição de acidificante; T2: ração-controle + 0,5 por cento de ácido fumárico; T3: ração-controle + 1,0 por cento de ácido fumárico; T4: ração-controle + 0,5 por cento de ácido fumárico +0,1 por cento de ácido butírico; T5: ração-controle + 0,5 por cento de ácido fumárico + 0,5 por cento de ácido fórmico; T6: ração-controle + 1,0 por cento de ácido fumárico + 0,1 por cento de ácido butírico e T7: ração-controle + 1,0 por cento de ácido fumárico +0,5 por cento de ácido fórmico), cinco repetições e seis animais por unidade experimental. O peso dos leitões aos 30 dias de idade não foi influenciado pelos tratamentos, mas houve efeito significativo de tratamento sobre ganho de peso e consumo alimentar diário no período de 15-30 dias de idade, com maior desempenho para os leitões alimentados com dietas suplementadas com ácido fumárico. Não houve efeito significativo dos tratamentos sobre o peso médio aos 36 dias, o ganho de peso, o consumo diário e a conversão alimentar dos leitões de 15 a 36 dias de idade. Houve diferença entre tratamentos para a altura do epitélio do duodeno, porém não houve diferença em relação à do jejuno e à do íleo. As eletromicrografias do duodeno dos leitões alimentados com as diferentes dietas experimentais revelaram vilosidades com características normais


Performance, morphological and morphometric characteristics of the small intestine of 210 recently weaned piglets, averaging 4.04 ± 0.66 kg, during two periods ( from 15 to 30 days of age and from 15 to 36 days of age) were evaluated in a randomized block experimental design with seven treatments, T1: control diet (CD); T2: CD + 0.5 percent fumaric acid; T3: CD + 1.0 percent fumaric acid; T4: CD + 0.5 percent fumaric acid + 0.1 percent butyric acid; T5: CD + 0.5 percent fumaric acid + 0.5 percent formic acid; T6: CD + 1,0 percent fumaric acid + 0.1 percent butyric acid and T7: CD + 1.0 percent fumaric acid + 0.5 percent formic acid, five replicates and six piglets per experimental unit. No effects of treatment (P<0.05) on body weight at 30 days of age was observed but significant differences between treatments were observed for daily weight gain and feed consumption from 15 to 30 days of age. Piglets fed supplemented acid fumaric diets had higher performance during this period. No significant effects of treatments on body weight at 36 days of age, daily weight gain, daily feed intake and feed conversion were observed (P>0.05) from 16 to 36 days of age. Significant differences (P<0.05) between treatments for duodenal epithelium height were observed, but not for jejunum and ileum epithelium heights. Normal villus patterns were observed in the electromicrographs of duodenum from piglets fed all different diets


Asunto(s)
Animales , Ácido Butírico/administración & dosificación , Dieta/veterinaria , Formicicum Acidum/administración & dosificación , Fumaricum Acidum/administración & dosificación , Aumento de Peso/fisiología , Intestino Delgado/anatomía & histología , Intestino Delgado , Porcinos/crecimiento & desarrollo , Destete
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