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1.
Toxicol Res ; 40(1): 11-21, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38223676

RESUMEN

Anthraquinone (anthracene-9,10-dione) is a multifaceted chemical used in the paper industry, in the production of synthetic dyes, in crop protection against birds and is released from fossil fuels. Additionally, the anthraquinone scaffold, when substituted with sugars and hydroxyl groups is found in plants as metabolites. Because of these multiple applications, it is produced on a large scale worldwide. However, its toxicological aspects have gained interest, due to the low limits in the foods defined by legislation. Worrying levels of anthracene-9,10-dione have been detected in wastewater, atmospheric air, soil, food packaging and more recently, in actual foodstuffs. Recent investigations aiming to identify the anthracene-9,10-dione contamination sources in teas highlighted the packaging, leaves processing, anthracene metabolism, reactions between tea constituents and deposition from the environment. In this context, this review seeks to highlight the uses, sources, biological effects, analytical and regulatory aspects of anthracene-9,10-dione.

2.
Ecotoxicol Environ Saf ; 203: 111010, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32888587

RESUMEN

Manganese (Mn) toxicity is common in plants grown on very acid soils. However, some plants species that grow in this condition can take up high amounts of Mn and are referred to as hyperaccumulating species. In this study, we evaluated the capacity of Ilex paraguariensis to accumulate Mn and the effect of excessive concentrations on plant growth and nutrition. For this, a container experiment was conducted using soils from different parent materials (basalt and sandstone), with and without liming, and at six doses of applied Mn (0, 30, 90, 270, 540 and 1,080 mg kg-1). Clonal plants grown for 203 days were harvested to evaluate yield, and leaf tissue samples were evaluated for Mn and other elements. Without liming and with high Mn doses, leaf Mn concentrations reached 13,452 and 12,127 mg kg-1 in sandstone and basalt soils, respectively; concentrations in excess of 10,000 mg kg-1 are characteristic of hyperaccumulating plants. Liming reduced these values to 7203 and 8030 mg kg-1. More plant growth accompanied increased Mn leaf concentrations, with a growth reduction noted at the highest dose in unlimed soils. Elemental distribution showed Mn presence in the mesophyll, primarily in vascular bundles, without high Mn precipitates. Interveinal chlorosis of young leaves associated with high Mn concentration and lower Fe concentrations was observed, especially in sandstone soil without liming. However, the occurrence of this symptom was not associated with decreased plant growth.


Asunto(s)
Ácidos/farmacología , Ilex paraguariensis/metabolismo , Manganeso/metabolismo , Enfermedades de las Plantas/inducido químicamente , Contaminantes del Suelo/metabolismo , Ácidos/análisis , Compuestos de Calcio/análisis , Compuestos de Calcio/farmacología , Ilex paraguariensis/efectos de los fármacos , Ilex paraguariensis/crecimiento & desarrollo , Hierro/metabolismo , Manganeso/análisis , Manganeso/toxicidad , Óxidos/análisis , Óxidos/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
3.
Food Res Int ; 120: 478-503, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31000264

RESUMEN

Functional and medicinal beverages consumption plays an important role in human health, considering that metabolites, with a wide range of pharmacological effects, are inserted in the human diet. Nowadays, the most consumed beverages are obtained from Camellia sinensis leaves and coffee grain processing, and contain different classes of polyphenols and phenolic acids in their phytochemical composition. Besides C. sinensis and coffee, numerous plants have been receiving attention due to their phytochemical composition and pharmacological effects, such as yerba mate, hibiscus, chamomile, lemongrass, fennel and mentha. Furthermore, atomized or lyophilized medicinal plant extracts can be employed in many beverage formulations and the consumption of these products is an excellent delivery means for nutrients and bioactive compounds, such as: minerals, vitamins, terpenes, antioxidants, saponins, alkaloids and polysaccharides. Innovation in food processing in order to insert functional and medicinal beverages in the human diet poses a challenge for the coming years. The technological development of new processing forms and use of plants with bioactive metabolites could be an important tool in relation to this proposal. In this context, this review has aimed to summarize and analyze pharmacological, phytochemistry and technological aspects of species with classical ethnobotanical and traditional use.


Asunto(s)
Bebidas , Alimentos Funcionales , Preparaciones de Plantas , Modelos Moleculares , Fitoquímicos/química , Plantas Medicinales/química
4.
Braz. arch. biol. technol ; 57(6): 997-1003, Nov-Dec/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-730406

RESUMEN

Ilex paraguariensis is a native species to South America. Its economic importance is in the use of its leaves and twigs in the processing of a product popularly known as "chimarrão". The aim of this study was to evaluate the correlations between some physico-chemical process parameters in the oxidation of I. paraguariensis leaves oxidation. The leaves of Maté with age 1.0, 6.5 and 12.0 months were subjected to an oxidation process for 3 h under different relative humidity conditions (80, 90 and 99%) at 26°C. The extracts were evaluated using the experimental design techniques to maximize the oxidation conditions for the total polyphenols, antioxidant capacity, water activity and color. The condition of 90% humidity and leaf age 6.5 months resulted in lower lightness and yellow color of the product. Green color was not significantly influenced by the studied parameters. The highest levels of total phenols and antioxidant potential were found when the leaf age was one month and humidity was 90%. Thus, it could be concluded that the air humidity of the chamber and leaf age influenced the oxidation process of the leaves of Maté as well as the antioxidant capacity of the extract obtained.

5.
Braz. arch. biol. technol ; 57(5): 663-667, Sep-Oct/2014.
Artículo en Inglés | LILACS | ID: lil-723058

RESUMEN

In Brazil, yerba mate is consumed after processing; however, in Chile and Uruguay, the consumers prefer the cured product, which acquires a yellow color. For that yerba-mate is stored for a period of six months to one year, which increases the cost of the final product for the overseas market. This study evaluated the effect of humidity and temperature in maturation chamber on the time required for the product to get this characteristic. The changes in the color, pH, moisture and water activity were evaluated during the time of storage in different conditions of temperature and humidity. Yerba-mate subjected to higher temperature and humidity showed nearest color of the product submitted to natural storage. The loss of green color was related to the reduction in pH and increase in the moisture of the samples. The higher humidity allowed the mate to reach conditions near to market requirements abroad in approximately 60 days of maturation.

6.
Ciênc. rural ; 42(4): 730-736, abr. 2012. ilus, tab
Artículo en Portugués | LILACS | ID: lil-623086

RESUMEN

Um dos maiores problemas do leite UHT é a sedimentação que ocorre durante o período de armazenamento, o que é muito reclamado pelos consumidores. O objetivo deste trabalho foi determinar a sedimentação em leite UHT integral, semidesnatado e desnatado, armazenados a 20°C e 30°C (±1°C) durante 120 dias. Nos leites pasteurizados que deram origem aos leites UHT, foram efetuadas análises físico-químicas e microbiológicas (bactérias mesófilas, psicrotróficas e láticas) e, nos leites UHT integral, semidesnatado e desnatado, avaliaram-se a acidez, pH, fervura, sensorial, integridade das embalagens e sedimentação, logo depois de embalados e no 30°, 60°, 90° e 120° dia de armazenamento. Os leites pasteurizados integral, semidesnatado e desnatado apresentaram resultados dentro dos padrões estipulados pela indústria para as bactérias mesófilas (log10 4,37 a log10 4,08UFC mL-1), psicrotróficas (log10 3,06 a log10 2,77UFC mL-1) e lácticas (log10 3,10 a log10 2,42UFC mL-1), que diferiram significativamente (P<0,05) das contagens dos leites in natura que lhes deram origem. Os valores de acidez (0,15% ácido láctico), crioscopia (-0,535 a -0,540°H), gordura, densidade (1,031 a 1,034g mL-1), ESD (8,65 a 8,93%) e pH (6,70 a 6,80) também ficaram dentro dos padrões. A partir do 60° dia de armazenamento foi observada sedimentação nos três tipos de leites UHT a 20°C (0,80 a 1,10g) e a 30°C (1,0 a 1,40g).


One of the biggest problems of UHT milk is the sedimentation of protein particles that occurs during the storage period, which faces rejection by the consumers. The aim of this study was to evaluate the particle sedimentation in semi-skimmed, skimmed and wholemilk, stored at 20°C, 30°C (±1) for 120 days. In pasteurized milk that yielded UHT milk physico-chemical and microbiological analisys (mesophilic, psychrotrophic and lactic acid bacteria) were carried out. In semi-skimmed, skimmed and whole milk, the acidity, pH, boiling, sensory analysis, integrity of packaging and sedimentation tests were carried out shortly after packing and at 30th, 60th, 90th and 120th days of storage. The pasteurized whole milk, semi skimmed and skimmed milk showed results within the required standards by the industry for mesophilic bacteria(log10 4.37 a log10 4.08UFC mL-1), psychrotrophic (log10 3.06 a log10 2.77UFC mL-1) and lactic acid (log10 3.10 a log10 2.42UFC mL-1) bacteria, that differed significantly (5%) of value of fresh milk from which they originate. The values of acidity (0.15% ác. láctic), freezing point (-0.535 a -0.540°H), fat, density (1.031 a 1.034g mL-1), pH (6.70 a 6.80) and degreased dry extract (8.65 a 8.93%) also were within the standards. From the 60th day of storage on, particle sedimentation was observed in the three types of UHT milk at the 20°C (0.80 a 1.10g) at the 30°C (1.0 a 1.40g).

7.
Ciênc. agrotec., (Impr.) ; 35(6): 1166-1171, Nov.-Dec. 2011. tab
Artículo en Inglés | LILACS | ID: lil-610608

RESUMEN

The adulteration of the product Ilex paraguariensis with other Ilex species is a mAjor problem for maté tea producers. In this work, three species of Ilex were evaluated for their volatile composition by headspace solid phase microextraction coupled to gas chromatography and mass spectrum detector (HS-SPME/GC-MS). The adulterating species I. dumnosa and I. theizans Mart. ex Reissek presented a different profile of volatile organic compounds when compared to I. paraguariensis. Aldehydes methyl-butanal, pentanal, hexanal, heptanal and nonanal were detected only in the adulterating species. This result suggests that such compounds are potential chemical markers for identification of adulteration and quality analysis of products based on Ilex paraguariensis.


A adulteração do produto Ilex paraguariensis com outras espécies de Ilex é um dos principais problemas dos produtores de erva-mate. Neste trabalho, três espécies de Ilex foram avaliadas quanto à sua composição volátil por microextração em fase sólida acoplada à cromatografia gasosa e detector de espectro de massas (HS-SPME/GC-MS). As espécies adulterantes I. dumnosa e I. theizans Mart. ex Reissek apresentaram um perfil diferente de compostos orgânicos voláteis, quando comparadas com a I. paraguariensis. Os aldeídos metil-butanal, pentanal, hexanal, heptanal e nonanal foram detectados apenas nas espécies adulterantes. Esse resultado sugere que esses compostos químicos são marcadores potenciais para a identificação de adulteração e análise da qualidade dos produtos à base de Ilex paraguariensis.

8.
Int J Food Sci Nutr ; 62(7): 703-10, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21591987

RESUMEN

The objective of this work is to evaluate the effects of the addition of dried extract from mate leaves on the oxidative stability (lipid and protein), microbiological characteristics (lactic and Micrococcaceae bacteria) and sensory attributes of formulations of Italian-type sausages. The different Italian-type sausages formulations tested in this work were in agreement with the legislation in terms of chemical and microbiological parameters. During storage, the formulation with 0.4 wt% of mate leaves extract presented lower thiobarbituric acid reactive substances and carbonyl values compared with the control, proving the antioxidant action of the extract. The sensory characteristics of flavour, texture and global acceptation were not affected by the addition of mate extract compared with the formulation with artificial antioxidant.


Asunto(s)
Antioxidantes/farmacología , Comportamiento del Consumidor , Ilex paraguariensis , Peroxidación de Lípido/efectos de los fármacos , Productos de la Carne/análisis , Extractos Vegetales/farmacología , Carbonilación Proteica/efectos de los fármacos , Animales , Grasas de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , Tecnología de Alimentos , Humanos , Oxidación-Reducción , Hojas de la Planta , Gusto , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
9.
Braz. arch. biol. technol ; 54(2): 337-345, Mar.-Apr. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-582383

RESUMEN

This work aimed to study the oxidation of leaves of Ilex paraguariensis St. Hil, in a process similar to the oxidation of Camellia sinensis, with the purpose of developing new products based on yerba maté. So far, no previous systematic study about the oxidation of yerba maté has been found elsewhere. A Plackett-Burman experimental design was used for the screening of the significant parameters that affected the oxidation. The oxidation was indirectly quantified by following the changes in the product color, water activity, and pH with the time of processing. The factors that most influenced the process were the age of the leaves and the relative humidity of the oxidation chamber. The differences between the treatments were more evident after 3, 6 12 and 24 h of oxidation. The results could contribute to the developing of new products based on I. paraguariensis St. Hil, increasing the profitability of cultivation of this native species.

10.
Hig. aliment ; 22(162): 77-82, jun. 2008. tab
Artículo en Portugués | LILACS | ID: lil-535533

RESUMEN

As propriedades medicinais do iogurte e da erva-mate na saúde humana são em grande parte conhecidas. Conseqüentemente, a união de ambos em um único produto traria muitos benefícios à saúde do consumidor, mas não se tem conhecimento da ação de alguns compostos presentes na erva-mate sobre o crescimento das bactérias láticas utilizadas no iogurte, uma vez que os benefícios à saúde estão relacionados com o desenvolvimento dessas bactérias. Por esse motivo, este trabalho teve como objetivo elaborar iogurte com leite desnatado, adicionado de extrato de erva-mate, e acompanhar a evolução das bactérias lácticas, pH e acidez durante o período de armazenamento de 45 dias a 8°C. O iogurte com extrato de erva-mate apresentou menor valor de pH e maior valor de acidez em relação ao iogurte padrão, sendo estes resultados decorrentes do bom desenvolvimento das bactérias lácticas, durante os trinta primeiros dias de armazenamento no iogurte com extrato de erva-mate. O extrato de erva-mate adicionado ao iogurte apresentou características favoráveis ao desenvolvimento das bactérias láticas.


Asunto(s)
Análisis de los Alimentos , Microbiología de Alimentos , Ilex paraguariensis , Yogur , Productos Lácteos Cultivados
11.
Braz. arch. biol. technol ; 51(3): 569-579, May-June 2008. graf, tab
Artículo en Inglés | LILACS | ID: lil-487750

RESUMEN

The bitterness intensity of beverage prepared from the leaves produced on the males and females of yerba mate (Ilex paraguariensis), grown in the forest understory and monoculture, was evaluated. The leaves were grouped by their position (in the crown and on the branch tips) and by the leaf age. The leaf gas exchange, leaf temperature and photosynthetic photon flux density were observed. Inter and intra-specific competition for light and self-shading showed the same effect on yerba mate beverage taste. All the shading types resulted in bitterer taste of the processed yerba mate leaves compared to the leaves originated under the direct sun exposure. The leaves from the plants grown in the monoculture showed less bitterness than those grown in the forest understory. This conclusion was completely opposite to the conventionally accepted paradigm of the yerba mate industries. The leaves from the tips (younger leaves) of the plants grown in the monoculture resulted a beverage of softer taste; the males produced less bitter leaves in any light environment (forest understory or in the crown in monoculture). The taste was related to the photosynthetic and transpiration rate, and leaf temperature. Stronger bitterness of the leaves provided from the shade conditions was related to the decreased leaf temperature and transpiration in the diurnal scale.


Mediu-se a intensidade de amargor da bebida preparada a partir de folhas da erva-mate (Ilex paraguariensis) de diversas idades, situadas em duas posições na copa (interior e ponteiras), produzidas por plantas masculinas e femininas cultivadas na floresta antropizada e em monocultura. As trocas gasosas foliares, a temperatura de folhas e a densidade de fluxo de fótons fotossinteticamente ativos também foram medidas. Com isso verificou-se que a idéia corrente de que o sombreamento está diretamente relacionado ao sabor suave do chimarrão é completamente equivocada, já que as competições inter- e intra-específicas por luz e auto-sombreamento provocaram o mesmo efeito no sabor do chimarrão, isto é, todos os tipos de sombreamento resultaram em sabor mais amargo de folhas processadas do de pleno sol. Assim, as folhas de plantas cultivadas em monocultura mostraram-se menos amargas do que aquelas de plantas manejadas sob a floresta. Além disso, as folhas de ponteiras (mais jovens) da monocultura originaram o chimarrão mais suave e os machos produziram folhas menos amargas que as fêmeas em ambos ambientes luminosos (floresta e monocultura). O sabor mostrou-se relacionado à fotossíntese, à transpiração e à temperatura de folha. Em sombreamento a modificação de sabor foi direcionada ao aumento de amargor e, aparentemente, relacionada ao decréscimo da temperatura de folhas e da transpiração na escala diurna.

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