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1.
J Sci Food Agric ; 99(2): 624-631, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29952005

RESUMO

BACKGROUND: Camu-camu (Myrciaria dubia) is a typical Amazonian fruit and has high antioxidant capacity due to its high levels of vitamin C and phenolic compounds. This study aimed to determine the phytochemicals, antioxidant capacity and antimutagenic effects of camu-camu fruits with different maturity stages grown in dry (commercial cultivation) or flooded environments (native cultivation, Amazon). RESULTS: Total polyphenols, ascorbic acid and in vitro antioxidant capacity levels were higher in ripe fruits grown in a commercial cultivation. The extracts from ripe camu-camu grown in a commercial cultivation exerted antioxidant effects and high percentage of protection against doxorubicin and 1,2-dimethylhydrazine in all tested systems (liver, bone marrow and gut), for three camu-camu extract concentrations (17, 85 and 170 mg kg-1 body weight), as follows: bone marrow minocronucleus (37.91%, 41.75%, 43.95%); micronucleus gut test (61.01%, 64.40%, 50.28%); apoptosis index (60.26%, 62.44%, 58.22%); comet assay through the tail moment (71.64%, 72.31%, 70.70%), percent DNA in the tail (64.54%, 68.75%, 76.79%) and tail intensity (76.43%, 81.02%, 68.33%). CONCLUSION: The results of this study contribute to increasing the production of camu-camu fruits grown in dry environments and their use as a health-promoting food. © 2018 Society of Chemical Industry.


Assuntos
Antimutagênicos/farmacologia , Frutas/química , Myrtaceae/química , Extratos Vegetais/farmacologia , Animais , Antimutagênicos/análise , Antioxidantes/análise , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Masculino , Camundongos , Myrtaceae/crescimento & desenvolvimento , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/análise
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 194: 172-180, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29331819

RESUMO

A new method was developed to determine the antioxidant properties of red cabbage extract (Brassica oleracea) by mid (MID) and near (NIR) infrared spectroscopies and partial least squares (PLS) regression. A 70% (v/v) ethanolic extract of red cabbage was concentrated to 9° Brix and further diluted (12 to 100%) in water. The dilutions were used as external standards for the building of PLS models. For the first time, this strategy was applied for building multivariate regression models. Reference analyses and spectral data were obtained from diluted extracts. The determinate properties were total and monomeric anthocyanins, total polyphenols and antioxidant capacity by ABTS (2,2-azino-bis(3-ethyl-benzothiazoline-6-sulfonate)) and DPPH (2,2-diphenyl-1-picrylhydrazyl) methods. Ordered predictors selection (OPS) and genetic algorithm (GA) were used for feature selection before PLS regression (PLS-1). In addition, a PLS-2 regression was applied to all properties simultaneously. PLS-1 models provided more predictive models than did PLS-2 regression. PLS-OPS and PLS-GA models presented excellent prediction results with a correlation coefficient higher than 0.98. However, the best models were obtained using PLS and variable selection with the OPS algorithm and the models based on NIR spectra were considered more predictive for all properties. Then, these models provided a simple, rapid and accurate method for determination of red cabbage extract antioxidant properties and its suitability for use in the food industry.


Assuntos
Antocianinas/análise , Antioxidantes/análise , Brassica/metabolismo , Extração Líquido-Líquido/métodos , Extratos Vegetais/química , Polifenóis/análise , Espectrofotometria Infravermelho/métodos , Algoritmos , Análise dos Mínimos Quadrados
3.
Food Chem Toxicol ; 45(5): 852-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17194516

RESUMO

Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. A number of studies have demonstrated that anthocyanins present antioxidant capacity and show inhibitory effects on the growth of some cancer cells. Thus, the goal of this study was to evaluate both the antimutagenicity/antigenotoxicity and mutagenicity/genotoxicity of aqueous extract obtained from the Solanum melanogena, a possible novel source of anthocyanin, and its main purified anthocyanin extract (delphinidin), using the single cell (comet) assay and micronucleus test. Pretreatment with higher doses of the purified anthocyanin (10 and 20mg/kg b.w.) led to a statistically significant reduction (p<0.05) in the frequency of micronuclei in polychromatic erythrocytes induced by cyclophosphamide. The pattern of reduction ranged from 48% to 57% independent of concentration. No apparent genotoxicity and mutagenicity was found for either the anthocyanin or delphinidin extracts. Taken together, these results suggest that mice pre-treated with specific compounds present in anthocyanins (delphinidin) displayed a lower incidence of mutations induced by cyclophosphamide. This finding emphasizes the potential of natural colorants to prevent mutations and also the applicability of genotoxic evaluation for improving health. Furthermore, the results presented here could be an additional argument to support the use of anthocyanins in the diet.


Assuntos
Antocianinas/toxicidade , Antioxidantes/toxicidade , Solanum melongena/química , Animais , Ensaio Cometa , Ciclofosfamida/toxicidade , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Masculino , Camundongos , Testes para Micronúcleos , Testes de Mutagenicidade , Extratos Vegetais/toxicidade
4.
J Med Food ; 15(2): 200-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22191630

RESUMO

Despite defenses by polymorphonuclear neutrophils in the host against invading agents, overproduction of oxidant species by phagocytes can lead to damage in the surrounding tissues. Several benzophenones have been shown to possess anti-inflammatory properties. The effect of the natural benzophenone 7-epiclusianone isolated from leaves of Garcinia brasiliensis was investigated by using in vitro antioxidant and ex vivo anti-inflammatory assays, focusing on the neutrophil respiratory burst and on the biochemical pathways involved. The bioactive extract, 7-epiclusianone, showed low in vitro antioxidant activity as evaluated by the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay, the reducing power test, or the chelating power assay. However, the benzophenone displayed potent activity in the ex vivo model of the neutrophil respiratory burst, inhibiting the generation of superoxide anions in a dose-dependent manner. When the respiratory burst was triggered by N-formyl-methionyl-leucyl-phenylalanine, a chemotactic peptide, the 50% effective concentration (EC(50)) was 41.18 µg/10(7) cells. When phagocytes were stimulated directly through protein kinase C via phorbol, the EC(50) was 34.3 µg/10(6) cells. The results indicated that 7-epiclusianone was able to down-regulate inflammatory phagocyte superoxide anion release through a mechanism controlled by tyrosine protein phosphorylation and by a direct stimulation of protein kinase C. These findings could lead to new therapeutic approaches for inflammation management and the development of new drugs.


Assuntos
Benzofenonas/farmacologia , Garcinia/química , Neutrófilos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Explosão Respiratória/efeitos dos fármacos , Superóxidos/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Neutrófilos/metabolismo
5.
J Pharm Biomed Anal ; 54(3): 451-7, 2011 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-20943341

RESUMO

A robust, direct, rapid and non-destructive X-ray diffraction crystallography method to detect the polyprenylated benzophenones 7-epi-clusianone (1) and guttiferone A (2) in extracts from Garcinia brasiliensis is presented. Powder samples of benzophenones 1 and 2, dried hexane extracts from G. brasiliensis seeds and fruit's pericarp, and the dried ethanolic extract from G. brasiliensis seeds were unambiguously characterized by powder X-ray diffractometry. The calculated X-ray diffraction peaks from crystal structures of analytes 1 and 2, previously determined by single-crystal X-ray diffraction technique, were overlaid to those of the experimental powder diffractograms, providing a practical identification of these compounds in the analyzed material and confirming the pure contents of the powder samples. Using the X-ray diffraction crystallography method, the studied polyprenylated benzophenones were selectively and simultaneously detected in the extracts which were mounted directly on sample holder. In addition, reference materials of the analytes were not required for analyses since the crystal structures of the compounds are known. High performance liquid chromatography analyses also were comparatively carried out to quantify the analytes in the same plant extracts showing to be in agreement with X-ray diffraction crystallography method.


Assuntos
Benzofenonas/análise , Cristalografia por Raios X , Frutas/química , Garcinia/química , Fitoterapia , Extratos Vegetais/análise , Sementes/química , Difração de Raios X , Benzofenonas/química , Benzoquinonas , Compostos Bicíclicos com Pontes/análise , Compostos Bicíclicos com Pontes/química , Cromatografia Líquida de Alta Pressão , Humanos , Extratos Vegetais/química , Pós/análise
6.
J Agric Food Chem ; 58(7): 4104-12, 2010 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-20205391

RESUMO

Many polyphenolics contained in mango have shown anticancer activity. The objective of this study was to compare the anticancer properties of polyphenolic extracts from several mango varieties (Francis, Kent, Ataulfo, Tommy Atkins, and Haden) in cancer cell lines, including Molt-4 leukemia, A-549 lung, MDA-MB-231 breast, LnCap prostate, and SW-480 colon cancer cells and the noncancer colon cell line CCD-18Co. Cell lines were incubated with Ataulfo and Haden extracts, selected on the basis of their superior antioxidant capacity compared to the other varieties, where SW-480 and MOLT-4 were statistically equally most sensitive to both cultivars followed by MDA-MB-231, A-549, and LnCap in order of decreasing efficacy as determined by cell counting. The efficacy of extracts from all mango varieties in the inhibition of cell growth was tested in SW-480 colon carcinoma cells, where Ataulfo and Haden demonstrated superior efficacy, followed by Kent, Francis, and Tommy Atkins. At 5 mg of GAE/L, Ataulfo inhibited the growth of colon SW-480 cancer cells by approximately 72% while the growth of noncancer colonic myofibroblast CCD-18Co cells was not inhibited. The growth inhibition exerted by Ataulfo and Haden polyphenolics in SW-480 was associated with an increased mRNA expression of pro-apoptotic biomarkers and cell cycle regulators, cell cycle arrest, and a decrease in the generation of reactive oxygen species. Overall, polyphenolics from several mango varieties exerted anticancer effects, where compounds from Haden and Ataulfo mango varieties possessed superior chemopreventive activity.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Mangifera/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/fisiopatologia , Polifenóis
7.
Bol. Centro Pesqui. Process. Aliment ; 22(1): 121-132, jan.-jun. 2004. graf
Artigo em Português | LILACS | ID: lil-384807

RESUMO

Curvas de secagem de banana passa foram determinadas, utilizando-se três temperaturas do ar de secagem. Os resultados indicaram que para reduzir o teor de unidade do produto até 23,5 por cento, foram necessários tempos de secagem de 51, 36 e 30 horas para as temperaturas de 50, 60 e 70ºC, respectivamente. O modelo exponencial U/u= exp(-kt) foi ajustaedo para os dados experimentais mediante análise de regressão não-linear, encontrando-se coeficiente de regressão linear. Determinou-se a atividade de água do produto ao longo do processo de secagem para as três temperaturas testadas. Estudou-se a correlação entre a atividade de água e o teor de unidade do produto, determinand-se as isotermas de dessorção da banana para a 25ºC. Observou-se que a atividade de água diminuiu em função do tempo de secagem e do teor de umidade para as três temperaturas de secagem. Os dados experimentais foram ajustados mediante regressão não-linear ao modelo polinormal e a seguinte equação foi obtida. O ajuste mostrou-se satisfatório (R2>0,90).


Assuntos
Conservação de Alimentos , Tecnologia de Alimentos , Zingiberales
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