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1.
Nutr Cancer ; 74(4): 1322-1337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34282687

RESUMO

The consumption of glucosinolate (GL)-rich foods, including Brassica vegetables, such as mustard, broccoli, and maca, is associated with decreased risk of developing cancer. The GL content in maca, which is recognized as a "superfood", is approximately 100-times higher than that in other brassicas. Although maca is a potential dietary source of GLs, limited studies have examined the bioactivity of maca GLs using the combination of chemical characterization and bioassays. In this study, the fractions (Lm-II and Lm-III) rich in intact GLs (glucotropaeolin and glucolimnanthin) were isolated and characterized from maca ethanolic extracts using chromatography and mass spectrometry. Additionally, the growth-inhibitory effects of Lm-II and Lm-II fractions against hepatocellular carcinoma (HepG2/C3A) and colon adenocarcinoma (HT29) cell lines were examined in the absence or presence of myrosinase (MYR). Fractions lacking low molecular weight sugars dose-dependently exerted cytotoxic effects in the presence of MYR. The half-maximal inhibitory concentration values of Lm-II and Lm-III against HepG2/C3A were 118.8 and 69.9 µg/mL, respectively, while those against HT29 were 102.6 and 71.5 µg/mL, respectively. These results suggest that the anticancer properties of maca can be attributed to GLs and corroborate the categorization of maca as a "superfood."Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.1952444.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Lepidium , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Glucosinolatos/análise , Glucosinolatos/farmacologia , Glicosídeo Hidrolases , Humanos , Lepidium/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia
2.
An Acad Bras Cienc ; 93(suppl 4): e20210047, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730621

RESUMO

The Agaricomycetes fungi produce various compounds with pharmaceutical, medicinal, cosmetic, environmental and biotechnological properties. In addition, some polysaccharides extracted from the fungal cell wall have antitumor and immunomodulatory actions. The aim of this study was to use genetic modification to transform Schizophyllum commune and identify if the phenotype observed (different from the wild type) resulted in changes of the cell wall polysaccharides. The plasmid pUCHYG-GPDGLS, which contains the Pleurotus ostreatus glucan synthase gene, was used in S. commune transformations. Polysaccharides from cell wall of wild (ScW) and mutants were compared in this study. Polysaccharides from the biomass and culture broth were extracted with hot water. One of the mutants (ScT4) was selected for further studies and, after hydrolysis/acetylation, the GLC analysis showed galactose as the major component in polysaccharide fraction from the mutant and glucose as the major monomer in the wild type. Differences were also found in the elution profiles from HPSEC and NMR analyses. From the monosaccharide composition it was proposed that mannogalactans are components of S. commune cell wall for both, wild and mutant, but in different proportions. To our knowledge, this is the first time that mannogalactans are isolated from S. commune liquid culture.


Assuntos
Schizophyllum , Parede Celular , Mutação/genética , Fenótipo , Polissacarídeos , Schizophyllum/genética
3.
Int J Biol Macromol ; 92: 1040-1048, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27514442

RESUMO

In vitro effects of acetylated pectin (OP) isolated from cacao pod husks (Theobroma cacao L.), its partially deacetylated and de-esterified form (MOP), and a commercial homogalacturonan (PG) were investigated on murine peritoneal macrophages. MOP stood out among the studied pectins. After 48h of incubation, compared with the control group, it was able to promote significant macrophage morphological differentiation from resident to activated stage and also stimulated nitric oxide production, which reached a level of 85% of that of LPS stimulus. In the presence of the highest tested concentration of MOP (200µg·mL-1), the levels of the cytokines TNF-α (6h) and IL-12 and IL-10 (48h) increased substantially in relation to untreated cells. Our results show that the partial deacetylation and de-esterification of pectin extracted from cacao pod husks (T. cacao L.) produced a polymer with greater ability than its native form to activate macrophages to a cytotoxic phenotype. Like this, they provide the possibility of a therapeutic application to MOP, which could lead to a decreased susceptibility to microbial infection besides antitumor activity. Additionally, the present results also corroborate with the proposition of that the chemical modifications of the biopolymers can result in an improved molecule with new possibilities of application.


Assuntos
Cacau/química , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Pectinas/farmacologia , Acetilação , Animais , Feminino , Expressão Gênica , Inflamação , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Camundongos , Óxido Nítrico/agonistas , Óxido Nítrico/biossíntese , Pectinas/química , Pectinas/isolamento & purificação , Cultura Primária de Células , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
4.
Mol Genet Genomics ; 289(5): 951-63, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24861101

RESUMO

Polyploid plants can exhibit transcriptional modulation in homeologous genes in response to abiotic stresses. Coffea arabica, an allotetraploid, accounts for 75% of the world's coffee production. Extreme temperatures, salinity and drought limit crop productivity, which includes coffee plants. Mannitol is known to be involved in abiotic stress tolerance in higher plants. This study aimed to investigate the transcriptional responses of genes involved in mannitol biosynthesis and catabolism in C. arabica leaves under water deficit, salt stress and high temperature. Mannitol concentration was significantly increased in leaves of plants under drought and salinity, but reduced by heat stress. Fructose content followed the level of mannitol only in heat-stressed plants, suggesting the partitioning of the former into other metabolites during drought and salt stress conditions. Transcripts of the key enzymes involved in mannitol biosynthesis, CaM6PR, CaPMI and CaMTD, were modulated in distinct ways depending on the abiotic stress. Our data suggest that changes in mannitol accumulation during drought and salt stress in leaves of C. arabica are due, at least in part, to the increased expression of the key genes involved in mannitol biosynthesis. In addition, the homeologs of the Coffea canephora subgenome did not present the same pattern of overall transcriptional response, indicating differential regulation of these genes by the same stimulus. In this way, this study adds new information on the differential expression of C. arabica homeologous genes under adverse environmental conditions showing that abiotic stresses can influence the homeologous gene regulation pattern, in this case, mainly on those involved in mannitol pathway.


Assuntos
Coffea/genética , Manitol/metabolismo , Vias Biossintéticas/genética , Coffea/metabolismo , Desidratação/metabolismo , Frutose/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Resposta ao Choque Térmico , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Transcrição Gênica
5.
Plant Physiol Biochem ; 49(4): 441-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21330144

RESUMO

Galactinol synthase (EC 2.4.1.123; GolS) catalyzes the first step in the synthesis of raffinose family oligosaccharides (RFOs). Their accumulation in response to abiotic stresses implies a role for RFOs in stress adaptation. In this study, the expression patterns of three isoforms of galactinol synthase (CaGolS1-2-3) from Coffea arabica were evaluated in response to water deficit, salinity and heat stress. All CaGolS isoforms were highly expressed in leaves while little to no expression were detected in flower buds, flowers, plagiotropic shoots, roots, endosperm and pericarp of mature fruits. Transcriptional analysis indicated that the genes were differentially regulated under water deficit, high salt and heat stress. CaGolS1 isoform is constitutively expressed in plants under normal growth conditions and was the most responsive during all stress treatments. CaGolS2 is unique among the three isoforms in that it was detected only under severe water deficit and salt stresses. CaGolS3 was primarily expressed under moderate and severe drought. This isoform was induced only at the third day of heat and under high salt stress. The increase in GolS transcription was not reflected into the amount of galactinol in coffee leaves, as specific glycosyltransferases most likely used galactinol to transfer galactose units to higher homologous oligosaccharides, as suggested by the increase of raffinose and stachyose during the stresses.


Assuntos
Adaptação Fisiológica , Coffea/metabolismo , Galactosiltransferases/metabolismo , Oligossacarídeos/metabolismo , Proteínas de Plantas/metabolismo , Rafinose/metabolismo , Estresse Fisiológico , Adaptação Fisiológica/genética , Coffea/genética , Dessecação , Expressão Gênica , Glicosiltransferases/metabolismo , Temperatura Alta , Folhas de Planta , Proteínas de Plantas/genética , Isoformas de Proteínas/metabolismo , Salinidade , Tolerância ao Sal , Cloreto de Sódio , Estresse Fisiológico/genética , Água
6.
Bioresour Technol ; 101(14): 5701-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20219363

RESUMO

The objective of this research was to evaluate the chemical composition, microstructure, and antioxidant capacity of king palm flour obtained from residues from organic king palm (Archontophoenix alexandrae) processing. King palm flour exhibited high levels of dietary fibre (70.85%) and total ash (3.27%); low contents of protein (3.51%) and lipid (0.91%). Iron, magnesium, calcium and potassium contents were 7.31, 517.03, 801.33 and 1041.95 mg/100g, respectively. The high concentration of glucose, xylose and arabinose suggests the presence of some polysaccharides, such as cellulose and hemicelluloses (xyloglucans and arabinoxylans). Methanol and aqueous extracts of king palm flour showed 1.27 and 0.95 mg/g (Gallic Acid Equivalents) of total polyphenols, respectively. Methanol extract yielded the best antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH()) and 2,2'-azino-di(3-ethylbenzthiazoline sulphonate) (ABTS()(+)) methods. The micrographs of leaf sheath showed the presence of druses, which are characterized as calcium oxalate deposition, contributing to the calcium content in king palm flour. The presence of primary and secondary cell walls lignified in leaf sheath contributed to high levels of dietary fibre detected in king palm flour.


Assuntos
Antioxidantes/química , Fibras na Dieta , Farinha , Benzotiazóis/química , Compostos de Bifenilo/química , Cálcio/química , Parede Celular/química , Celulose/química , Flavonoides/química , Alimentos , Glucanos/química , Metanol/química , Microscopia de Fluorescência/métodos , Ciências da Nutrição , Fenóis/química , Picratos/química , Folhas de Planta/metabolismo , Polifenóis , Ácidos Sulfônicos/química , Xilanos/química
7.
Hig. aliment ; 22(166/167): 105-108, nov.-dez. 2008. tab
Artigo em Português | LILACS | ID: lil-549290

RESUMO

A utilização de polpas como opção para enriquecer iogurte tem sido bem aceita pela indústria. O consumo de frutos típicos agrega valor ao produto final e representa um novo nicho de mercado a ser explorado. Os frutos do Psidium cattleianum Sabine (araçá vermelho) apresentam em média 12,42g, 2,8cm de diâmetro, têm como apelo mercadológico as suas características sensoriais exóticas, cor atrativa e flavor inconfundível e um elevado valor nutricional, rico em sais minerais e compostos antioxidantes como vitamina C e compostos fenólicos. Para verificar o índice de aceitabilidade do iogurte enriquecido utilizou-se escala hedônica estruturada com 9 pontos, correspondendo a desgostei muitíssimo (1) e gostei muitíssimo(9). O perfil reológico é um atributo de grande importância no processo de fabricação do iogurte, pois são adicionados ao leite outros ingredientes, que contribuem para a consistência do produto. (...) A adição de preparado de polpa de araçá promoveu a estabilidade da viscosidade e elevou o valor nutricional do produto, oferecendo boas perspectivas de consumo, tornando-se assim, mais uma alternativa de utilização do fruto in natura e a introdução no mercado de nova opção de aroma e sabor.


Assuntos
Tecnologia de Alimentos , Geleia de Frutas , Psidium , Iogurte
8.
Hig. aliment ; 22(166/167): 105-108, nov.-dez. 2008. tab
Artigo em Português | VETINDEX | ID: vti-45377

RESUMO

A utilização de polpas como opção para enriquecer iogurte tem sido bem aceita pela indústria. O consumo de frutos típicos agrega valor ao produto final e representa um novo nicho de mercado a ser explorado. Os frutos do Psidium cattleianum Sabine (araçá vermelho) apresentam em média 12,42g, 2,8cm de diâmetro, têm como apelo mercadológico as suas características sensoriais exóticas, cor atrativa e flavor inconfundível e um elevado valor nutricional, rico em sais minerais e compostos antioxidantes como vitamina C e compostos fenólicos. Para verificar o índice de aceitabilidade do iogurte enriquecido utilizou-se escala hedônica estruturada com 9 pontos, correspondendo a desgostei muitíssimo (1) e gostei muitíssimo(9). O perfil reológico é um atributo de grande importância no processo de fabricação do iogurte, pois são adicionados ao leite outros ingredientes, que contribuem para a consistência do produto. As análises reológicas foram realizadas em reômetro HAAKE RS 75 Rheoestress, acoplado a um controlador de temperatura Peltier (TC81) com termocirculador de água DC5B3. Os testes foram realizados em temperatura de 25°C. O sensor utilizado para as amostras de suco e iogurte, foi o cilindro-coaxial (Z-41). A adição de polpa de araçá vermelho elevou o teor de minerais e a textura do iogurte, que apresentou bom índice de aceitabilidade: 30% dos provadores escolheram a opção gostei muitíssimo e 44% gostei muito. A adição de preparado de polpa de araçá promoveu a estabilidade da viscosidade e elevou o valor nutricional do produto, oferecendo boas perspectivas de consumo, tornando-se assim, mais uma alternativa de utilização do fruto in natura e a introdução no mercado de nova opção de aroma e sabor.(AU)


The use of pulps as option to enrich yogurt has been well accepts for the industry. The consumption of typicalfruits joins value to the final product and it represents a new market niche to be explored. The fruits of the Psidiumcattleianum Sabine (red araçá) they presented 12,42g on average, 2,8cm of diameter have as appeal theirmarket exotic sensorial characteristics due to the, attractive color and unmistakable flavor and a high rich nutritional value in mineral and composed salts antioxidant as vitamin C and composed phenolics. To verify the index of acceptability of the enriched yogurt I was used climbs hedonic structured with 9 points, corresponding her displeased very much (1) and liked very much (9). The profile rheologic is an attribute of great importance in the process of yogurt production, because, they are added to the milk other ingredients, that you/they contribute to the consistence of the product. The analyses rheological were accomplished in rheomet HAAKE RS 75 Rheoestress, coupled her/it a temperature controller Peltier (TC81) with thermal circulation of water DC5B3. The tests were accomplished in temperature of 25°C. The sensor used for the juice samples and yogurt, it was the cylinder-coax (Z-41). The addition of pulp of red araçá elevated the tenor of minerals and the texture of the yogurt, that it presented good acceptability index: 30% of the fitting room chose the option liked very much and 44% liked a lot. The addition of mixture of araçá pulp promoted the stability of the viscosity and it elevated the nutritional value of the product, offering good consumption perspectives, becoming like this, one more alternative of use of the fruit in nature and theintroduction in the market of new aroma option and flavor. (AU)


Assuntos
Iogurte , Geleia de Frutas , Psidium , Tecnologia de Alimentos
9.
Int J Biol Macromol ; 38(3-5): 180-90, 2006 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-16542718

RESUMO

A general structural characterization and an investigation on the dynamics of formation of cell wall polysaccharides was performed, using plantlets stem samples from a typical gymnosperm from southern Brazil, Araucaria angustifolia, as experimental model. Microscopic examination and monosaccharide composition of plantlet segments at different heights were carried out to show the representative portions of stem cell wall development. The plantlets were divided in portions (tip, middle and base) which were submitted to sequential extractions. The extraction with water gave rise to large amounts of pectic material in the three portions and more highly substituted pectins occurred in the tip portion of the stems. Increase in alkali concentration extracted, respectively, higher amounts of xyloglucan structurally similar to those from dicotyledons. However, oligosaccharides containing galactose and fucose where found in higher amounts in base than tip portion. The changes in cell wall composition suggest that the development in gymnosperm cell walls follow the same key events as found in dicotyledon walls (type I).


Assuntos
Parede Celular/metabolismo , Cycadopsida/metabolismo , Carboidratos/química , Cromatografia , Cromatografia por Troca Iônica , Germinação , Hidrólise , Espectroscopia de Ressonância Magnética , Monossacarídeos/química , Monossacarídeos/metabolismo , Fenômenos Fisiológicos Vegetais , Polissacarídeos/química , Sementes/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Ácidos Urônicos/química
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