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1.
Plant Foods Hum Nutr ; 77(1): 1-11, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35233705

RESUMO

Coffee is one of the most valued consumer products. Surprisingly, there is limited scientific knowledge about the biochemical processes during the storage of green coffee that affects its sensory quality. This review analyzes the impact of the different variables involved in the green coffee storage on quality from a chemical point of view. Further, it highlights the relationship between the physiological processes of the grain, its viability, and shelf-life. Notably, the storage conditions and postharvest treatment affect both the longevity and the sensory quality of the coffee, probably due to the biological behavior of green coffee. Various studies found modifications in their chemical profiles involving carbohydrates, lipids, proteins/amino acids, and phenolic compounds. To make future studies more comparable, we recommend standardized protocols for evaluating and linking the sensory coffee quality with instrumental analysis methods and pre-defined settings for experimental storage conditions.


Assuntos
Coffea , Café , Coffea/química , Café/química
2.
Photochem Photobiol ; 98(1): 211-219, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34289116

RESUMO

The photoprotective and antioxidant activities of extracts of six species of plants collected in a high mountain ecosystem at 3150 m.a.s.l. were evaluated. In vitro photoprotection according to UVA-UVB absorption spectrum, Sun Protection Factor (SPF), UVA Protection Factor (UVAPF), (critical wavelength) λc and UVA/UVB Ratio were assessed. Also, the antioxidant activity was determined using the DPPH radical assay and the inhibition of lipid peroxidation in methyl linoleate (MeLo). Total anthocyanins content (TAC) and total polyphenolic content (TPC) were evaluated. Among the extracts evaluated, the extract of B. antioquensis, an endemic plant of Colombia, showed a significant photoprotection against UVA-UVB range, with SPF values of 15 ± 2 and UVAPF of 7 ± 1, λc : 378, UVA/UVB Ratio: 0.78. Furthermore, this extract presented an excellent antioxidant activity, with EC50 of 0.17 ± 0.04 g of dry extract/mmol DPPH, a value of TPC of 464 ± 9 mg gallic acid equivalents (GAE)/g dry extract and significant inhibition of MeLo peroxidation. The results suggest that the extract of B. antioquensis has the best quality to be a source of new UV filters, with a broad spectrum of protection and antioxidant properties.


Assuntos
Antioxidantes , Protetores Solares , Antocianinas , Antioxidantes/química , Antioxidantes/farmacologia , Ecossistema , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas , Protetores Solares/química , Protetores Solares/farmacologia , Raios Ultravioleta
3.
Physiol Plant ; 165(1): 4-16, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29493786

RESUMO

Cluster root (CR) is one of the most spectacular plant developmental adaptations to hostile environment. It can be found in a few species from a dozen botanical families, including white lupin (Lupinus albus) in the Fabaceae family. These amazing structures are produced in phosphate-deprived conditions and are made of hundreds of short roots also known as rootlets. White lupin is the only crop bearing CRs and is considered as the model species for CR studies. However, little information is available on CRs atypical development, including the molecular events that trigger their formation. To provide insights on CR formation, we performed an anatomical and cellular description of rootlet development in white lupin. Starting with a classic histological approach, we described rootlet primordium development and defined eight developmental stages from rootlet initiation to their emergence. Due to the major role of hormones in the developmental program of root system, we next focussed on auxin-related mechanisms. We observed the establishment of an auxin maximum through rootlet development in transgenic roots expressing the DR5:GUS auxin reporter. Expression analysis of the main auxin-related genes [TIR, Auxin Response Factor (ARF) and AUX/IAA] during a detailed time course revealed specific expression associated with the formation of the rootlet primordium. We showed that L. albus TRANSPORT INHIBITOR RESPONSE 1b is expressed during rootlet primordium formation and that L. albus AUXIN RESPONSE FACTOR 5 is expressed in the vasculature but absent in the primordium itself. Altogether, our results describe the very early cellular events leading to CR formation and reveal some of the auxin-related mechanisms.


Assuntos
Lupinus/crescimento & desenvolvimento , Proteínas de Plantas/genética , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Lupinus/anatomia & histologia , Lupinus/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/citologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas
4.
Photochem Photobiol ; 92(5): 742-52, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27416883

RESUMO

In the quest for new natural agents of photoprotection, we evaluated the photoprotective and antioxidant activity of B. antioquensis leaf extracts as well as its phenolic composition. The methanolic extract treated with activated carbon showed the highest absorption coefficients for UVA-UVB radiation, as well as an antioxidant capacity comparable to butylated hydroxy toluene. Furthermore, the formulation containing this extract showed suitable sensorial and photostable characteristics for topical use, and significant values of UVAPF, critical wavelength (λc ), UVA/UVB ratio and sun protection factor (5.3, 378 nm, 0.78 and 9.1 ± 0.1, respectively). In addition, three glycoside derivatives of quercetin, a kaempferol glycoside and a derivative of caffeic acid were the main polyphenolic compounds identified. These results demonstrate the potential of B. antioquensis extracts to be used as active components of novel, natural sunscreens.


Assuntos
Baccharis/química , Extratos Vegetais/farmacologia , Fator de Proteção Solar , Protetores Solares/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Glicosídeos/química , Glicosídeos/farmacologia , Quempferóis/química , Quempferóis/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/química , Quercetina/farmacologia , Protetores Solares/química
5.
Food Sci Technol Int ; 22(8): 699-707, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27091150

RESUMO

The physicochemical, compositional and functional properties of flour from green plantains (Musa acuminata) of the large green plantain variety, oyster mushrooms (Pleorotus ostreatus), pineapple peel (Ananas comosus) of the 'apple pineapple' variety, yellow peas (Pisum sativum), chickpeas (Cicer arietinum), whole grain rice (Oryza sativa), whole grain corn (Zea mays) and whole grain white quinoa (Chenopodium quinoa) were evaluated by using one-way analysis of variance, Pearson correlations and principal component analysis chemical composition of the eight flours, statistically differed (p < 0.05). Oyster mushroom and yellow pea flours had the greatest protein content (28.92 and 21.02%, respectively), whereas the pineapple peel, peas and corn stood out for their high contents of Fe and Zn. All flours exhibited emulsifying and foaming activities, while hydration and interfacial properties showed statistically significant negative correlations. There was a clear relationship between levels of protein and carbohydrates and gelation and syneresis phenomena in thermally treated flour suspensions. According to principal component analysis of functional, physicochemical and compositional properties, flours were classified into five groups of raw materials: (1) yellow peas, (2) chickpeas, rice, corn and quinoa, (3) green plantain, (4) pineapple peel and (5) oyster mushrooms. Results are promising to formulate mixes and composite flours for fortification and/or enrichment of food products by using different technological processes.


Assuntos
Farinha/análise , Análise de Alimentos , Chenopodium quinoa/química , Cicer/química , Colômbia , Manipulação de Alimentos , Micronutrientes/análise , Oryza/química , Pisum sativum/química , Proteínas de Plantas/análise , Grãos Integrais/química , Zea mays/química
6.
Photochem Photobiol ; 92(1): 150-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26481216

RESUMO

Currently, plants have gained widespread interest as a source of natural sunscreen. Specifically, plants from high altitude ecosystems are exposed to high UVR levels; therefore, they must produce an adaptive chemical response. The aim of this study was to evaluate the photo-protection and antioxidant capacity in vitro of nine plants from high altitude ecosystems in Antioquia, Colombia (Sphagnum meridense, Calamagrostis effusa, Lycopodiella alopecuroides, Morella parvifolia, Baccharis antioquensis, Pentacalia pulchella, Castilleja fissifolia, Hesperomeles ferruginea and Hypericum juniperinum). B. antioquensis and P. pulchella extracts showed the best results over a broad spectrum UVA-UVB with antioxidant capacity in vitro. However, B. antioquensis extracts presented the highest absorption coefficient in UVB-UVA range among plants under study. Furthermore, the gel formulation containing the crude extract of B. antioquensis showed significant values of UVAPF, UVA/UVB ratio, critical wavelength (λc ) and SPF (3, 0.78 380 nm and 4.73 ± 0.26; respectively), indicating interesting photostability and antiradical capacities. All of these properties could be improve in order to satisfy the requirements for broad-spectrum UVB/UVA protection. Finally, P. pulchella and B. antioquensis extracts could be a potential source of a new natural sunscreen compounds with photostable and antiradical properties.


Assuntos
Altitude , Antioxidantes/farmacologia , Ecossistema , Plantas/metabolismo , Protetores Solares/farmacologia , Colômbia , Técnicas In Vitro
7.
Vitae (Medellín) ; 18(1): 63-71, ene.-abr. 2011. graf, ilus, tab
Artigo em Inglês | LILACS | ID: lil-601522

RESUMO

The use of sunscreen products is very important nowadays. The photostability of UV filters incorporated in these products must be preserved during its storing and application processes in order to achieve the claims about photoprotection of the commercial products. The photostability of avobenzone, one of the most common UVA filters in commercial sunscreens, is assessed in solvents intended for cosmetic formulations. The study is carried out by following the spectral behavior of avobenzone solutions under irradiation and after storing them in the dark. Different photobehaviors of the avobenzona are found in the selected solvents, some of which can be explained in the same way than in analytical solvents; but for others, the structural and physical properties of the solvents must be taken into account. The most appropriate solvents for ensuring the photostability of avobenzona are mineral oil and isopropyl myristate.


El uso de antisolares es muy importante en la actualidad. La fotoestabilidad de los filtros UV usados en estos productos se debe conservar durante su almacenamiento y aplicación, con el fin de cumplir su papel fotoprotector. La fotoestabilidad de la avobenzona, uno de los filtros UVA más usados en la preparación de antisolares comerciales, es evaluada, por primera vez, en solventes cosméticos. Este estudio es llevado a cabo siguiendo el comportamiento espectral de soluciones de avobenzona cuando es sometida a irradiación, y luego de su almacenamiento en la oscuridad. La avobenzona presenta un comportamiento diferente en cada solvente, en algunos casos este comportamiento se puede explicar en la misma forma que en los solventes grado analítico, pero en otros se deben tener en cuenta las propiedades estructurales y fisicas del solvente. Los solventes donde la avobenzona es fotoestable son el aceite mineral y el miristato deisopropilo.


Assuntos
Luz , Protetores contra Radiação , Radiação , Radiação Solar
8.
Vitae (Medellín) ; 10(1): 35-43, sept. 2002-mar. 2003. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-353594

RESUMO

Ciertas asociaciones de excipientes y principios activos pueden ocasionar inestabilidad de éstos últimos hemos detectado que el alprazolam presenta incompatibilidades con algunos excipientes farmacéuticos. Se evalúa la incompatibilidad química del alprazolam con ocho excipientes que son usados en la formulación de comprimidos, en condiciones de estrés (temperatura y humedad). Cuatro de ellos presentan grupos carbonilo en su estructura química: ácido cítrico, carboximetilcelulosa, (PVPK15) y estearato de magnesio y los otros cuatro no lo presentan: almidón, metilcelulosa, talco, lactosa. La mayor degradación se obtiene con el primer grupo. El avance de la degradación se determina por la formación del principal producto de degradación del alprazolam: la triazolaminoquinoleina, el cual se cuantifica por espectrofotometría UV


Assuntos
Comprimidos , Alprazolam , Incompatibilidade de Medicamentos , Excipientes Farmacêuticos
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