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1.
J Sci Food Agric ; 91(10): 1849-54, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21452174

RESUMEN

BACKGROUND: Herbs and spices have been used as food preservatives, flavorings, and in traditional medicines for thousands of years. More and more scientific evidence supports the medicinal properties of culinary herbs. Colon cancer is the third leading cause of cancer death in the USA, and the fourth most common form of cancer worldwide. The objectives of this study were to evaluate the antitumor activity of five selected herbs grown under greenhouse conditions, and to study the potential synergistic effects among different herbal extract combinations. RESULTS: Thyme, rosemary, sage, spearmint, and peppermint extracts significantly inhibited SW-480 colon cancer cell growth, with sage extracts exhibiting the highest bioactivity, with 50% inhibition at 35.9 µg mL⁻¹, which was equivalent to 93.9 µg dried leaves mL⁻¹ of culture medium. Some mixtures of different herbal extracts had combination effects on cancer cell growth. The inhibitory effects of peppermint + sage combinations at a 1:1 ratio were significantly higher than rosemary + sage combinations at 1:1 ratio, although peppermint extracts showed lower inhibition than rosemary extracts. CONCLUSION: Extracts from herb species (thyme, rosemary, sage, spearmint and peppermint) can significantly inhibit the growth of human colon cancer cells. Mixtures of herb extracts can have combination effects on cancer cell growth. The study suggests that these five herbs may have potential health benefits to suppress colon cancer.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Lamiaceae , Fitoterapia , Extractos Vegetales/uso terapéutico , Agricultura/métodos , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Quimioterapia Combinada , Humanos , Lamiaceae/crecimiento & desarrollo , Extractos Vegetales/farmacología , Hojas de la Planta , Plantas Medicinales/crecimiento & desarrollo , Especias
2.
J Sci Food Agric ; 90(6): 1063-70, 2010 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-20355148

RESUMEN

BACKGROUND: Increasing evidence supports the potential health benefits of herbal extracts displaying antioxidant, anti-inflammatory and antitumour activities. Environment can have a pronounced effect on phenolic content and antioxidant capacity. The objectives of this study were to evaluate the total phenolic contents and antioxidant capacities of five different herbs grown under greenhouse and field conditions and to assess their potential anti-inflammatory effects. RESULTS: High total polyphenolic (TPP) content (measured by the Folin-Ciocalteu reagent method) and high Trolox equivalent antioxidant capacity (TEAC) were observed in all herbs evaluated. Leaves from thyme, sage, spearmint and peppermint grown in the greenhouse showed significantly higher TPP content and TEAC than those grown under field conditions, with a threefold difference being observed in peppermint. Rosemary, spearmint and peppermint extracts showed stronger inhibition of cyclooxygenase COX-2 than of COX-1. CONCLUSION: The results show that producing herbs under greenhouse conditions can improve their biological activities by increasing TPP contents and antioxidant capacities. The selective inhibition of COX-2 activity by rosemary, spearmint and peppermint suggests that they may be useful as anti-inflammatory agents with fewer side effects than regular non-steroidal drugs.


Asunto(s)
Agricultura/métodos , Antioxidantes/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Flavonoides/análisis , Lamiaceae , Fenoles/análisis , Extractos Vegetales/farmacología , Plantas Medicinales , Ciclooxigenasa 1/metabolismo , Inhibidores de la Ciclooxigenasa 2/análisis , Ambiente , Ambiente Controlado , Lamiaceae/química , Lamiaceae/crecimiento & desarrollo , Lamiaceae/metabolismo , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Plantas Medicinales/química , Plantas Medicinales/crecimiento & desarrollo , Plantas Medicinales/metabolismo , Polifenoles , Especias
3.
PLoS One ; 3(10): e3591, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18974891

RESUMEN

Individual mice have a unique odor, or odortype, that facilitates individual recognition. Odortypes, like other phenotypes, can be influenced by genetic and environmental variation. The genetic influence derives in part from genes of the major histocompatibility complex (MHC). A major environmental influence is diet, which could obscure the genetic contribution to odortype. Because odortype stability is a prerequisite for individual recognition under normal behavioral conditions, we investigated whether MHC-determined urinary odortypes of inbred mice can be identified in the face of large diet-induced variation. Mice trained to discriminate urines from panels of mice that differed both in diet and MHC type found the diet odor more salient in generalization trials. Nevertheless, when mice were trained to discriminate mice with only MHC differences (but on the same diet), they recognized the MHC difference when tested with urines from mice on a different diet. This indicates that MHC odor profiles remain despite large dietary variation. Chemical analyses of urinary volatile organic compounds (VOCs) extracted by solid phase microextraction (SPME) and analyzed by gas chromatography/mass spectrometry (GC/MS) are consistent with this inference. Although diet influenced VOC variation more than MHC, with algorithmic training (supervised classification) MHC types could be accurately discriminated across different diets. Thus, although there are clear diet effects on urinary volatile profiles, they do not obscure MHC effects.


Asunto(s)
Conducta Alimentaria/fisiología , Perfilación de la Expresión Génica , Percepción Olfatoria/genética , Olfato/genética , Alimentación Animal/análisis , Animales , Dieta , Femenino , Complejo Mayor de Histocompatibilidad/genética , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Odorantes , Orina/química , Volatilización
4.
J Agric Food Chem ; 56(24): 11700-6, 2008 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-19035656

RESUMEN

Blueberry extracts have high antioxidant potential and increase phase II enzyme activities in vitro. This study tested the hypothesis that blueberries would reduce DNA damage and lipid peroxidation and increase phase II enzyme activities in vivo. Young, healthy male Sprague-Dawley rats (n = 8 per group) were fed control AIN-93 diets or AIN-93 diets supplemented with blueberries or blueberry extracts for 3 weeks. Diets were supplemented with 10% freeze-dried whole blueberries, blueberry polyphenol extract and sugars to match the 10% blueberry diet, or 1 and 0.2% blueberry flavonoids, which were primarily anthocyanins. Liver and colon mucosa glutathione-S-transferase (GST), quinone reductase, and UDP-glucuronosyltransferase activities in colon mucosa and liver were not significantly increased by freeze-dried whole blueberries or blueberry fractions. Liver GST activity, however, was approximately 25% higher than controls for the freeze-dried whole blueberry, blueberry polyphenol, and 1% flavonoid groups. DNA damage was significantly lower than control only in the liver of animals fed the 1% flavonoid diet. The level of urinary F(2)-isoprostanes, a measure of lipid peroxidation, was unaffected. In summary, in healthy rats, short-term supplementation with freeze-dried whole blueberries, blueberry polyphenols, or blueberry flavonoids did not significantly increase phase II enzyme activities. However, supplementation with 1% blueberry flavonoids did decrease oxidative DNA damage in the liver.


Asunto(s)
Antioxidantes/farmacología , Arándanos Azules (Planta)/química , Colon/enzimología , Daño del ADN/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Hígado/enzimología , Extractos Vegetales/farmacología , Animales , Antioxidantes/química , Colon/efectos de los fármacos , Glucuronosiltransferasa/metabolismo , Glutatión Transferasa/metabolismo , Hígado/efectos de los fármacos , Masculino , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley
5.
J Agric Food Chem ; 55(7): 2705-13, 2007 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-17348670

RESUMEN

Recent research suggests that blueberries are rich in total polyphenols and total anthocyanins. Phenolic compounds are highly unstable and may be lost during processing, particularly when heat treatment is involved. There is no systematic study available providing information on the fate of phenolic compounds during storage and how that affects their biological activity. We provide a systematic evaluation of the changes observed in total polyphenols (TPP), total anthocyanins (TACY), Trolox equivalent antioxidant capacity (TEAC), phenolic acids, and individual anthocyanins of blueberry extract stored in glass bottles and the ability of blueberry extract to inhibit cell proliferation. The extract was stored at different temperatures (-20 +/- 1, 6 +/- 1, 23 +/- 1, and 35 +/- 1 degrees C). Two cultivars, Tifblue and Powderblue, were chosen for the study. The recoveries of TPP, TACY, and TEAC in blueberry extract after pressing and heating were approximately 25, approximately 29, and approximately 69%, respectively, for both cultivars. The recovery of gallic acid, catechin, and quercetin was approximately 25%. Ferulic acid was not detected in the final extract in both Tifblue and Powderblue cultivars. The recovery of peonidin, malvidin, and cyanidin glycosides was approximately 20% in the final extract in both cultivars. Losses due to storage were less when compared with initial losses due to processing. At -20 degrees C, no statistically significant loss of TPP, TACY, and TEAC was observed up to 30 days (P < 0.05). At 6 degrees C storage, there was a significant loss observed from 15 to 30 days. Similar results were obtained at 23 and 35 degrees C (P < 0.05). There was retention of more than 40% of ellagic and quercetin after 60 days at 35 +/- 1 degrees C. Anthocyanins were not detected after 60 days of storage at 35 +/- 1 degrees C. Significant retention (P < 0.05) was obtained for malvidin (42.8 and 25.8%) and peonidin (74.0 and 79.5%) after 60 days of storage at 23 +/- 1 degrees C in glass bottles for Tifblue and Powderblue, respectively, when compared with other individual anthocyanins. A linear relationship was observed between TEAC values and total polyphenols or total anthocyanins. A cell viability assay was performed using HT-29 cancer cell lines and anthocyanins extracted from 30, 60, and 90 days of stored extract at 6 +/- 1 and 23 +/- 1 degrees C. A significant cell proliferation inhibition percentage was observed in 30 days, although this was reduced significantly after 30-90 days. These results suggest that heating and storage conditions significantly affect the phenolic compounds and their biological activities. Frozen and low temperature storage are suggested for blueberry extract in order to retain the bioactive components.


Asunto(s)
Antocianinas/análisis , Arándanos Azules (Planta)/química , Flavonoides/análisis , Conservación de Alimentos/métodos , Frutas/química , Vidrio , Fenoles/análisis , Antioxidantes/análisis , Manipulación de Alimentos , Embalaje de Alimentos , Extractos Vegetales/química , Polifenoles
6.
J Agric Food Chem ; 54(15): 5651-8, 2006 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-16848559

RESUMEN

Recent studies have shown that dietary polyphenols may contribute to the prevention of cardiovascular disease and cancer. Anthocyanins from different plant sources including blueberries have been shown to possess potential anticancer activities. One of the key factors needed to correctly relate the in vitro study results to human disease outcomes is information about bioavailability. The objectives of the current study were to evaluate the absorption of blueberry anthocyanin extracts using Caco-2 human intestinal cell monolayers and investigate the effects of different aglycones, sugar moieties, and chemical structure on bioavailability of different types of anthocyanins. The results of this study showed that anthocyanins from blueberries could be transported through the Caco-2 cell monolayers although the transport/absorption efficiency was relatively low compared to other aglycone polyphenols. The transport efficiency of anthocyanins averaged approximately 3-4% [less than 1% in delphinidin glucoside (Dp-glc)]. No significant difference in transport/absorption efficiency was observed among three blueberry cultivars. The observed trends among different anthocyanins generally agreed well with some published in vivo results. Dp-glc showed the lowest transport/absorption efficiency, and malvidin glucoside (Mv-glc) showed the highest transport/absorption efficiency. Our result indicates that more free hydroxyl groups and less OCH(3) groups can decrease the bioavailability of anthocyanins. In addition, cyanindin glucoside (Cy-glc) showed significantly higher transport efficiency than cyanidin galactoside (Cy-gal), and peonidin glucoside (Pn-glc) showed significantly higher transport efficiency than peonidin galactoside (Pn-gal), indicating that glucose-based anthocyanins have higher bioavailability than galactose-based anthocyanins.


Asunto(s)
Antocianinas/farmacocinética , Frutas/química , Absorción Intestinal , Vaccinium/química , Antocianinas/metabolismo , Disponibilidad Biológica , Transporte Biológico , Células CACO-2 , Humanos
7.
Ann Bot ; 97(1): 57-63, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16287904

RESUMEN

BACKGROUND AND AIMS: Fertilization is essential in almond production, and pollination can be limiting in production areas. This study investigated stigma receptivity under defined developmental stages to clarify the relationship between stigma morphology, pollen germination, tube growth and fruit set. METHODS: Light and scanning electron microscopy were employed to examine stigma development at seven stages of flower development ranging from buds that were swollen to flowers in which petals were abscising. Flowers at different stages were hand pollinated and pollen germination and tube growth assessed. Artificial pollinations in the field were conducted to determine the effect of flower age on fruit set. KEY RESULTS: Later stages of flower development exhibited greater stigma receptivity, i.e. higher percentages of pollen germination and more extensive tube growth occurred in older (those opened to the flat petal stage or exhibiting petal fall) than younger flowers. Enhanced stigma receptivity was associated with elongation of stigmatic papillae and increased amounts of stigmatic exudate that inundated papillae at later developmental stages. Field pollinations indicated that the stigma was still receptive and nut set was maintained in older flowers. CONCLUSIONS: Stigma receptivity in almond does not become optimal until flowers are past the fully open stage. The stigma is still receptive and fruit set is maintained in flowers even at the stage when petals are abscising. Strategies to enhance pollination and crop yield, including the timing and placement of honey bees, should consider the effectiveness of developmentally advanced flowers.


Asunto(s)
Flores/crecimiento & desarrollo , Prunus/crecimiento & desarrollo , Flores/anatomía & histología , Flores/ultraestructura , Frutas/crecimiento & desarrollo , Infertilidad Vegetal/fisiología , Prunus/anatomía & histología , Reproducción/fisiología , Factores de Tiempo
8.
J Agric Food Chem ; 53(22): 8804-12, 2005 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-16248588

RESUMEN

Muscadine grapes have unique aroma and flavor characteristics. Although a few studies reported high polyphenols content of muscadine grapes, little research has been conducted to evaluate the phenolic compounds bioactivities in any muscadine grape cultivar. The objective of this study was to evaluate the effect of phenolic compounds in muscadine grapes on cancer cell viability and apoptosis. Four cultivars of muscadine (Carlos, Ison, Noble, and Supreme) were assessed in this study. Phenolic compounds were extracted from muscadine skins and further separated into phenolic acids, tannins, flavonols, and anthocyanins using HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC. Anthocyanin fractions were more than 90% pure. The effect of different fractions on the viability and apoptosis of two colon cancer cell lines (HT-29 and Caco-2) was evaluated. A 50% inhibition of cancer cell population growth for the two cell lines was observed at concentrations of 1-7 mg/mL for crude extracts. The phenolic acid fractions showed a 50% inhibition at the level of 0.5-3 mg/mL. The greatest inhibitory activity was found in the anthocyanin fraction, with a 50% inhibition at concentrations of approximately 200 microg/mL in HT-29 and 100-300 microg/mL in Caco-2. Anthocyanin fractions also resulted in 2-4 times increase in DNA fragmentation, indicating the induction of apoptosis. These findings suggest that polyphenols from muscadine grapes may have anticancer properties.


Asunto(s)
Antineoplásicos/análisis , Frutas/química , Fenoles/análisis , Vitis/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Células CACO-2 , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Células HT29 , Humanos , Hidrólisis , Fenoles/farmacología , Polifenoles , Proantocianidinas/análisis
9.
J Agric Food Chem ; 53(18): 7320-9, 2005 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16131149

RESUMEN

Research has shown that diets rich in phenolic compounds may be associated with lower risks of several chronic diseases including cancer. This study systematically evaluated the bioactivities of phenolic compounds in rabbiteye blueberries and assessed their potential antiproliferation and apoptosis induction effects using two colon cancer cell lines, HT-29 and Caco-2. Polyphenols in three blueberry cultivars, Briteblue, Tifblue, and Powderblue, were extracted and freeze-dried. The extracts were further separated into phenolic acids, tannins, flavonols, and anthocyanins using an HLB cartridge and LH20 column. Some individual phenolic acids and flavonoids were identified by HPLC with >90% purity in anthocyanin fractions. The dried extracts and fractions were added to the cell culture medium to test for antiproliferation activities and induction of apoptosis. Flavonol and tannin fractions resulted in 50% inhibition of cell proliferation at concentrations of 70-100 and 50-100 microg/mL in HT-29 and Caco-2 cells, respectively. The phenolic acid fraction showed relatively lower bioactivities with 50% inhibition at approximately 1000 microg/mL. The greatest antiproliferation effect among all four fractions was from the anthocyanin fractions. Both HT-29 and Caco-2 cell growth was significantly inhibited by >50% by the anthocyanin fractions at concentrations of 15-50 microg/mL. Anthocyanin fractions also resulted in 2-7 times increases in DNA fragmentation, indicating the induction of apoptosis. The effective dosage levels are close to the reported range of anthocyanin concentrations in rat plasma. These findings suggest that blueberry intake may reduce colon cancer risk.


Asunto(s)
Apoptosis/efectos de los fármacos , División Celular/efectos de los fármacos , Neoplasias del Colon/patología , Frutas/química , Fenoles/farmacología , Vaccinium/química , Células CACO-2 , Cromatografía Líquida de Alta Presión , Células HT29 , Humanos , Fenoles/aislamiento & purificación
10.
J Agric Food Chem ; 53(2): 442-51, 2005 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-15656686

RESUMEN

Total phenolics, ascorbic acid, and betalain contents of differently colored cactus pear clones (nine Opuntia ficus-indica [L.] Mill. clones and one O. robusta Wendl. clone) were investigated and related to their respective antioxidant potential assessed by Trolox-equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays. TEAC and ORAC values were very highly correlated with each other and also with values for total phenolics, betalain contents, and ascorbic acid concentrations. Total phenolics had the greatest contribution to ORAC and TEAC values. High-performance liquid chromatography (HPLC)-diode array detector (DAD)-tandem mass spectrometry (MS/MS) measurements of cactus pear juices permitted the differentiation of the clones based on variations in pigment patterns and betalain concentrations. The red and yellow betalains were absent in lime green colored cactus fruits. The ratio and concentration of these pigments were responsible for the yellow, orange, red, and purple colors in the other clones. Progeny of purple and lime green colored parents were characterized by 12% and 88% of plants bearing lime green and purple fruit, respectively. This implies that the genes for betalain production were lacking in the lime green fruits but could be provided by a parent with a complete set of genes, that is, purple fruits. Besides known pigments typical of Cactaceae, two unexpected betalains were identified. Whereas gomphrenin I was found for the first time in tissues of cactus plants, methionine-betaxanthin has never been described before as a genuine betalain. In addition to their alleged health-promoting properties, various combinations of yellow betaxanthins and red-purple betacyanins may allow the development of new food products without using artificial colorants.


Asunto(s)
Antioxidantes/análisis , Color , Frutas/química , Opuntia/química , Compuestos de Amonio Cuaternario/análisis , Ácido Ascórbico/análisis , Betalaínas , Opuntia/genética , Fenoles/análisis , Pigmentos Biológicos/análisis
11.
Ann Bot ; 91(3): 335-41, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12547686

RESUMEN

Fungicides can be detrimental to flower development, pollen function and fruit set in a number of crops. Almond is a self-incompatible nut crop that has a fruit set of only approx. 30 % of the total number of flowers. Thus, interference of pollination and fertilization by fungicide sprays is of concern, and identification of chemicals having the least detrimental effects would be desirable. The objective of this study was to evaluate the effect of fungicide sprays on stigma morphology in almond using a laboratory spray apparatus that simulated field applications. Four fungicides (azoxystrobin, myclobutanil, iprodione and cyprodinil) were applied, and fresh, unfixed stigmatic surfaces were observed using a scanning electron microscope at 4 and 24 h after spraying. Increased exudate accumulation was induced by azoxystrobin at both time periods, and localized damage and collapse of stigmatic cells were observed after 24 h. Damaged stigmatic papillae exhibited wrinkling, surface distortion or collapse. Likewise, myclobutanil caused significant damage to and collapse of papillae; these were more extensive at later observations. Iprodione had no effect on exudate accumulation but caused marked and severe collapse of stigmatic papillae which was pronounced at 24 h. Cyprodinil promoted a copious increase in exudate secretion and caused the most severe collapse of stigmatic cells of all the fungicides evaluated. Damage was somewhat localized at 4 h but more global at 24 h. This study has verified that certain fungicide sprays have direct detrimental effects on stigma morphology and enhance exudate production in almond flowers.


Asunto(s)
Flores/efectos de los fármacos , Fungicidas Industriales/efectos adversos , Prunus/efectos de los fármacos , Flores/fisiología , Flores/ultraestructura , Fungicidas Industriales/administración & dosificación , Prunus/fisiología , Prunus/ultraestructura , Rodaminas
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