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1.
Int J Mol Sci ; 24(11)2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37298671

RESUMEN

Protein-based biostimulants (PBBs) have a positive effect on plant development, although the biological background for this effect is not well understood. Here, hydrolyzed wheat gluten (HWG) and potato protein film (PF) in two levels (1 and 2 g/kg soil) and in two different soils (low and high nutrient; LNC and HNC) were used as PBBs. The effect of these PBBs on agronomic traits, sugars, protein, and peptides, as well as metabolic processes, were evaluated on sugar beet in comparison with no treatment (control) and treatment with nutrient solution (NS). The results showed a significant growth enhancement of the plants using HWG and PF across the two soils. Sucrose and total sugar content in the roots were high in NS-treated plants and correlated to root growth in HNC soil. Traits related to protein composition, including nitrogen, peptide, and RuBisCO contents, were enhanced in PBB-treated plants (mostly for HWG and PF at 2 g/kg soil) by 100% and >250% in HNC and LNC, respectively, compared to control. The transcriptomic analysis revealed that genes associated with ribosomes and photosynthesis were upregulated in the leaf samples of plants treated with either HWG or PP compared to the control. Furthermore, genes associated with the biosynthesis of secondary metabolites were largely down-regulated in root samples of HWG or PF-treated plants. Thus, the PBBs enhanced protein-related traits in the plants through a higher transcription rate of genes related to protein- and photosynthesis, which resulted in increased plant growth, especially when added in certain amounts (2 g/kg soil). However, sucrose accumulation in the roots of sugar beet seemed to be related to the easy availability of nitrogen.


Asunto(s)
Beta vulgaris , Beta vulgaris/metabolismo , Nitrógeno/metabolismo , Desarrollo de la Planta , Suelo , Sacarosa/metabolismo , Raíces de Plantas/metabolismo
2.
Genes (Basel) ; 13(9)2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-36140673

RESUMEN

The western part of South America is a centre of diversity for tomatoes, but genetic diversity studies are lacking for parts of that region, including Bolivia. We used 11 simple sequence repeat (SSR) markers (including seven novel markers) to evaluate genetic diversity and population structure of 28 accessions (four modern cultivars, four advanced lines, nine landraces, 11 wild populations), and to compare their genetic variation against phenotypic traits, geographical origin and altitude. In total, 33 alleles were detected across all loci, with 2-5 alleles per locus. The top three informative SSRs were SLM6-11, LE20592 and TomSatX11-1, with polymorphism information content (PIC) of 0.65, 0.55 and 0.49, respectively. The genetic diversity of Bolivian tomatoes was low, as shown by mean expected heterozygosity (He) of 0.07. Analysis of molecular variance (AMOVA) revealed that 77.3% of the total variation was due to variation between accessions. Significant genetic differentiation was found for geographical origin, cultivation status, fruit shape, fruit size and growth type, each explaining 16-23% of the total variation. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) tree and principal coordinate analysis (PCoA) scatter plot both revealed differentiation between accessions with determinate flowers and accessions with indeterminate flowers, regardless of cultivation status. The genetic profiles of the accessions suggest that the Bolivian tomato gene pool comprises both strictly self-pollinating and open-pollinating genotypes.


Asunto(s)
Solanum lycopersicum , Bolivia , Variación Genética/genética , Solanum lycopersicum/genética , Repeticiones de Microsatélite/genética , Polimorfismo Genético
3.
Artículo en Inglés | MEDLINE | ID: mdl-32244813

RESUMEN

Human consumption of fruits and vegetables are generally below recommended levels. Waste from the production, e.g., of un-used parts such as broccoli leaves and stem when producing broccoli florets for food, is a sustainability issue. In this study, broccoli leaves were analyzed for the content of various dietary fibre and phenolics, applying the Uppsala method and HPLC analyses, respectively. The results showed that broccoli leaves had comparable levels of dietary fibre (26%-32% of dry weight (DW)) and phenolic compounds (6.3-15.2 mg/g DW) to many other food and vegetables considered valuable in the human diet from a health perspective. A significant positive correlation was found among soluble dietary fibre and phenolic acids indicating possible bindings between these components. Seasonal variations affected mainly the content of conjugated phenolics, and the content of insoluble dietary fibre. This study verified the importance of the use of broccoli production side streams (leaves) as they may contribute with health promoting components to the human diet and also socio-economic and environmental benefits to the bioeconomic development in the society.


Asunto(s)
Brassica , Ingredientes Alimentarios , Hojas de la Planta , Brassica/química , Clima , Ingredientes Alimentarios/análisis , Humanos , Fenoles/análisis , Hojas de la Planta/química
4.
Food Chem ; 210: 541-50, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27211680

RESUMEN

Rose hip fruit, which contains high concentration of carotenoids is commonly used for different food products in Europe and it is considered to have medical properties. In this study, a simple, rapid and efficient HPLC-DAD-APCI(+)-MS method was developed and applied to identify and quantify the carotenoids in rose hip fruit of four rose species, including both unsaponified and saponified extract. In the unsaponified extract 23 carotenoid esters were detected, in which either rubixanthin ester or violaxanthin ester was the dominant component of the ester composition. In the saponified extract 21 carotenoids, including 11 xanthophylls and 10 carotenes were detected. This is the first time the total carotenoid composition, including the carotenoid esters in rose hip fruit were identified and quantified. This work reveals the potential of rose hip fruit to be utilized as a healthy dietary material and give chemical information for the possible future development in the pharmacology field.


Asunto(s)
Carotenoides/análisis , Cromatografía Líquida de Alta Presión/métodos , Ésteres/análisis , Frutas/química , Rosa/química , Europa (Continente) , Espectrometría de Masas/métodos , Saponinas , Xantófilas
5.
J Sci Food Agric ; 96(6): 2161-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26147234

RESUMEN

BACKGROUND: For health promotion and as part of natural plant protection, it might be of interest to increase the content of oleanolic acid (OA) and ursolic acid (UA) by biofortification in breeding programs, although the extent of the influence of genetic and environmental factors needs to be clarified. The objective of this study was to determine the effect of cultivar, sun exposure, storage, bruising and fungal infection on the OA and UA content in apple peel. RESULTS: Three apple cultivars with different ripening times--'Discovery' (early), 'Aroma' (middle) and 'Gloster' (late)--were investigated. The content of OA and UA was mainly influenced by cultivar and side subjected to sun exposure, and to a minor extent by storage and seasonal year. 'Gloster' had the highest OA and UA content of the investigated cultivars. OA and UA content on the shaded side was higher than that on the sun-exposed side in all three cultivars. Inoculation with Penicillium expansum did not have any consistent effect on OA or UA, except in a few cases where the levels decreased. CONCLUSION: OA and UA content can be increased by choice of cultivar in the breeding process and to some extent by cultural practice.


Asunto(s)
Frutas/química , Malus/metabolismo , Ácido Oleanólico/química , Penicillium/fisiología , Luz Solar , Triterpenos/química , Almacenamiento de Alimentos , Frutas/metabolismo , Frutas/microbiología , Concentración de Iones de Hidrógeno , Malus/química , Malus/genética , Ácido Oleanólico/metabolismo , Factores de Tiempo , Triterpenos/metabolismo , Ácido Ursólico
6.
Foods ; 5(3)2016 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-28231155

RESUMEN

This study assessed the concentrations of three falcarinol-type polyacetylenes (falcarinol, falcarindiol, falcarindiol-3-acetate) in carrots and the correlations between these and different soil traits. A total of 144 carrot samples, from three different harvests taken a single season, were analysed in terms of their polyacetylene concentrations and root development. On one of the harvesting occasions, 48 soil samples were also taken and analysed. The chemical composition of the soil was found to influence the concentrations of falcarinol-type polyacetylenes in carrots. When the total soil potassium level was 200 mg/100 g soil, the concentration of falcarindiol (FaDOH) in the carrot samples was 630 µg/g DW, but when carrots were grown in soil with a total potassium level of 300 mg/100 g soil, the FaDOH concentration in the carrots fell to 445 µg/g DW. Carrots grown in soils generally low in available phosphorus exhibited higher levels of falcarindiol if the soil was also low in available magnesium and calcium. The concentrations of polyacetylenes in carrots were positively correlated with total soil phosphorus level, but negatively correlated with total soil potassium level. Of the three polyacetylenes analysed, FaDOH concentrations were influenced most by changes in soil chemical composition.

7.
Int J Environ Res Public Health ; 12(11): 14068-83, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26540066

RESUMEN

In this study, 33 spring and winter wheat genotypes were analyzed for carotenoid content and composition. Investigated genotypes were divided into four genotype groups i.e., spelt, landraces, old cultivars and primitive wheat. The results showed a high level of variation among the genotypes in amount of carotenoids in the grain with high values (around 4 mg/Kg) especially in one of the genotypes-Öland 8. Lutein was the most common carotenoid in all the investigated genotypes, contributing 70%-90% of the carotenoids in the grain. Variation in carotenoid content and composition was found not only among genotypes, but also between genotype groups and wheat type, although there is a need to analyze more genotypes to confirm the differences found between groups and types. This study showed that 40% of the daily requirements of lutein can be achieved from the genotypes with the highest lutein content (Öland 8) produced using organic farming through the average human consumption of 200 grams of wheat per day. Furthermore, this study showed, by the use of principal component analyses, an opportunity to select genotypes combining high values of certain nutritional compounds. By a further breeding and commercial production of such genotypes, the nutritional value of wheat flour for human consumption can be improved.


Asunto(s)
Carotenoides/análisis , Grano Comestible/química , Harina/análisis , Alimentos Orgánicos/análisis , Valor Nutritivo , Triticum/química , Triticum/genética , Carotenoides/genética , Grano Comestible/genética , Variación Genética , Genotipo , Humanos , Agricultura Orgánica , Suecia
8.
Int J Environ Res Public Health ; 11(4): 3870-93, 2014 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-24717360

RESUMEN

An increasing interest in organic agriculture for food production is seen throughout the world and one key reason for this interest is the assumption that organic food consumption is beneficial to public health. The present paper focuses on the background of organic agriculture, important public health related compounds from crop food and variations in the amount of health related compounds in crops. In addition, influence of organic farming on health related compounds, on pesticide residues and heavy metals in crops, and relations between organic food and health biomarkers as well as in vitro studies are also the focus of the present paper. Nutritionally beneficial compounds of highest relevance for public health were micronutrients, especially Fe and Zn, and bioactive compounds such as carotenoids (including pro-vitamin A compounds), tocopherols (including vitamin E) and phenolic compounds. Extremely large variations in the contents of these compounds were seen, depending on genotype, climate, environment, farming conditions, harvest time, and part of the crop. Highest amounts seen were related to the choice of genotype and were also increased by genetic modification of the crop. Organic cultivation did not influence the content of most of the nutritional beneficial compounds, except the phenolic compounds that were increased with the amounts of pathogens. However, higher amounts of pesticide residues and in many cases also of heavy metals were seen in the conventionally produced crops compared to the organic ones. Animal studies as well as in vitro studies showed a clear indication of a beneficial effect of organic food/extracts as compared to conventional ones. Thus, consumption of organic food seems to be positive from a public health point of view, although the reasons are unclear, and synergistic effects between various constituents within the food are likely.


Asunto(s)
Alimentos Orgánicos , Animales , Contaminación de Alimentos/análisis , Alimentos Orgánicos/análisis , Humanos , Metales Pesados/análisis , Agricultura Orgánica , Residuos de Plaguicidas/análisis , Salud Pública
9.
J Sci Food Agric ; 92(10): 2116-21, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22311859

RESUMEN

BACKGROUND: Rose hips are used as a food ingredient and in health products. They are rich in various bioactive compounds such as carotenoids and vitamin C, but data on their vitamin E content (tocopherols and tocotrienols) are limited. In this study, four different species of Rosa were analysed for tocopherol and tocotrienol content during ripening in three different years. RESULTS: Only α- and γ-tocopherol were found in the fleshy parts of the rose hips, and the tocopherol content and vitamin E activity varied depending on date of harvesting, species and year. The amount of vitamin E activity differed between species of Rosa and years, whereas the changes during ripening were relatively small. CONCLUSION: The choice of species must be considered if tocopherol content is to be optimised when rose hips are used as a food ingredient.


Asunto(s)
Frutas/metabolismo , Rosa/metabolismo , Vitamina E/metabolismo , alfa-Tocoferol/metabolismo , gamma-Tocoferol/metabolismo , Dieta , Humanos , Rosa/clasificación , Especificidad de la Especie
10.
J Sci Food Agric ; 92(8): 1748-54, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22190221

RESUMEN

BACKGROUND: Carrot roots contain polyacetylenes, reported to be both beneficial and distasteful when consumed by humans. This study aimed to investigate the relationships between polyacetylene contents, root morphology and sugar content in order to increase the opportunities to optimise the composition of polyacetylenes in carrots. RESULTS: The falcarinol/total polyacetylene ratio was positively correlated with root size, the amount of sucrose and the sucrose/total soluble sugar ratio among both fresh and stored samples. Root size was inversely correlated with the amounts of falcarindiol and falcarindiol-3-acetate, especially among stored samples. Stored carrots exhibited an inverse correlation between polyacetylenes and the amount of soluble sugar. At a falcarinol content at harvest below approximately 200 mg kg(-1) dry weight the amounts of all polyacetylenes increased during storage, but above that level the amounts of all polyacetylenes instead decreased. CONCLUSION: The results indicate similarities in the activity of the enzymes transforming sucrose to hexoses and the enzymes transforming falcarinol to falcarindiol-3-acetate and falcarindiol. The negative correlation between root size and polyacetylenes seems to be partly due to dilution but also to a higher synthetisation rate in smaller roots. The results indicate the existence of an equilibrium regulating the level of falcarinol.


Asunto(s)
Daucus carota/metabolismo , Sacarosa en la Dieta/metabolismo , Diinos/metabolismo , Enzimas/metabolismo , Alcoholes Grasos/metabolismo , Almacenamiento de Alimentos , Raíces de Plantas/anatomía & histología , Sacarosa/metabolismo , Daucus carota/enzimología , Dieta , Hexosas/metabolismo , Humanos , Solubilidad
11.
J Agric Food Chem ; 58(22): 11703-8, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-20964297

RESUMEN

The amounts of three main polyacetylenes in carrots; falcarinol, falcarindiol, and falcarindiol-3-acetate, were determined by HPLC, during three seasons, in carrots harvested several times per season and at different locations in Sweden. The amounts of falcarindiol first decreased from a relatively high level and then increased later in the harvest season. The amounts of falcarindiol-3-acetate showed similar variations, whereas the amounts of falcarinol did not exhibit any significant variation during the harvest season. During storage the amount of polyacetylenes leveled off, increasing in samples initially low and decreasing in samples initially high in polyacetylenes. The amounts of all polyacetylenes varied significantly due to external factors and between stored and fresh samples. This variation opens up possibilities to achieve a chemical composition of polyacetylenes at harvest that minimizes the risk of bitter off-taste and maximizes the positive health effects reported in connection with polyacetylenes in carrots.


Asunto(s)
Manipulación de Alimentos/métodos , Extractos Vegetales/análisis , Poliinos/análisis , Daucus carota/química
12.
J Agric Food Chem ; 58(4): 2323-30, 2010 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-20099844

RESUMEN

Effects of heat treatment and storage on quercetin and isorhamnetin content, major and minor components of isorhamnetin, and quercetin glucosides and aglycone, were investigated in onion (Allium cepa L.). The sweet onion 'Recorra' and red onions 'Hyred' and 'Red Baron' were cultivated in the south part of Norway and thereafter stored for eight months. The onions were either not field dried, but stored directly, or field dried and then stored, or field dried and then heat treated before storage. Neither storage nor heat treatment caused any major differences in total flavonol content in the investigated sweet onion as well as in the red onion cultivars. The two major quercetin glucosides differed in their changes in content during storage; quercetin-4'-glucoside did not show any consistent changes during storage in the two red cultivars, independent of treatment, whereas quercetin-3,4'-diglucoside increased significantly by 30 or 51%, respectively, during storage in 'Hyred' and 'Red Baron' in the 24 h heat treated onions. Isorhamnetin-4'-glucoside, which might possibly be of special interest from a human health point of view, was present at 2-3 times higher amount in the sweet onion cultivar than in the two red cultivars. Some of the quercetin glucosides present at lower concentrations, isorhamnetin-3,4'-diglucoside, quercetin-3,7,4'-triglucoside, and quercetin-7,4'-diglucoside, increased during storage in all treatments in both 'Hyred' and 'Red Baron', though sometimes a decrease was found at the end of storage.


Asunto(s)
Allium/química , Flavonoles/análisis , Quercetina/análisis , Allium/clasificación , Allium/crecimiento & desarrollo , Antioxidantes/análisis , Cromatografía Líquida de Alta Presión/métodos , Flavonoles/química , Conservación de Alimentos/métodos , Glucósidos/análisis , Calor , Humanos , Noruega
13.
Am J Bot ; 97(11): 1884-93, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21616827

RESUMEN

PREMISE OF THE STUDY: Storage oil (triacylglycerol) accumulates in tissues such as the embryo and endosperm of seeds and the fruit mesocarp, but seldom in underground organs. As a rare exception, cultivated variants of yellow nutsedge (Cyperus esculentus) contain high amounts of both oil and starch in the mature tubers. • METHODS: Biochemical analyses and light and electron microscopy were used to study the accumulation patterns of storage nutrients in developing nutsedge tubers. • KEY RESULTS: During the initial phase of tuber development, the conducting rhizome tissue is transformed into a storage compartment, then massive storage reserves accumulate in the tuber. At the beginning of tuber development, a large sugar load coincided with the onset of starch accumulation. Oil accumulation started later, concomitant with a substantial drop in the sugar content. Initially, oil accumulated at a lower rate compared to starch, but the rate later increased; after 6 wk, oil made up 24% of tuber dry mass, while starch made up 32%. Protein concentration changed only a small amount throughout this development. Oil and starch accumulated in the same cells throughout the tubers in a sequential fashion during tuber development. • CONCLUSIONS: The developmental pattern in the build up of storage nutrients in the tubers highlights nutsedge as a novel model plant, having potential to significantly widen our understanding on how synthesis of storage reserves, and in particular oils, is regulated and directed in nonseed tissues such as tubers and roots.

14.
J Agric Food Chem ; 57(1): 250-8, 2009 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-19125686

RESUMEN

Four cultivars of sea buckthorn berries were analyzed for their carotenoid and chlorophyll contents during ripening in three consecutive years. The different carotenoids generally increased in concentration during ripening and comprised from 120 to 1425 microg/g of DW of total carotenoids (1.5-18.5 mg/100 g of FW) depending on cultivar, harvest time, and year. GLM analyses revealed the effect of cultivar to be considerably larger than that of year and harvest time. The content of pheophytin a, a chlorophyll a derivate, steadily decreased during berry ripening. Pheophytin a therefore acted as a marker of the degree of ripening of sea buckthorn berries and was used here to convert harvest date into an estimated ripening time.


Asunto(s)
Carotenoides/análisis , Frutas/química , Frutas/crecimiento & desarrollo , Hippophae/química , Feofitinas/análisis , Biomarcadores/análisis , Especificidad de la Especie , Factores de Tiempo
15.
J Agric Food Chem ; 56(15): 6701-6, 2008 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-18642927

RESUMEN

Sea buckthorn berries ( Hippophae rhamnoides L.) are used in foods, cosmetics, and pharmaceutical products. They are of particular interest for their high content of healthy phytochemicals, including vitamin E-related compounds (tocopherols and tocotrienols). This study investigated the content of tocopherols and tocotrienols during ripening in berries from four cultivars of sea buckthorn over a three-year period. The results showed large variations in tocopherols and tocotrienols depending on harvest date, cultivar, and year. Levels of alpha-tocopherol were higher early in the ripening period, while at later dates, delta-tocopherol levels increased. Great differences in amounts and composition of tocopherols and tocotrienols were observed between cultivars. Tocopherol levels were positively correlated with daily temperature, but this trend varied between years. Variations in tocopherols and tocotrienol levels in sea buckthorn berries due to cultivar, year, and ripening stage should therefore be considered in the production of nutritional products.


Asunto(s)
Frutas/química , Frutas/crecimiento & desarrollo , Hippophae/química , Tocoferoles/análisis , Tocotrienoles/análisis , Clima , Estaciones del Año , Factores de Tiempo
16.
J Agric Food Chem ; 56(2): 361-7, 2008 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-18163553

RESUMEN

Field-cured onions cv. Hyskin ( Allium cepa L.) supplied with organic nitrogen fertilizer were studied. The fertilizer was applied by broadcasting and harrowing, broadcasting and rotary cultivation, or placement between rows. Nitrogen dynamics were monitored throughout the growing season by soil sampling. Variation in quercetin content in the onion scales was analyzed by HPLC. The organically fertilized onions were compared with inorganically fertilized onions grown in the same field. Inoculation with arbuscular mycorrhizal fungi (AMF) in the row at sowing or during commercial transplant production was tested but did not significantly affect mycorrhizal root colonization levels in the field. Onions that received no fertilizer at all or that had fertilizer placed between rows had better establishment, probably due to more favorable soil nitrogen concentrations for seedling emergence. Broadcast application led to higher nitrogen concentration in the root zone, resulting in fewer but larger individual onions. Quercetin levels were not significantly altered as a result of nitrogen fertilizer source (inorganic or organic), application method, or mycorrhizal inoculation. However, variation between years was significant, with quercetin levels in 2004 almost twice as high as those in 2005.


Asunto(s)
Fertilizantes , Alimentos Orgánicos , Nitrógeno/análisis , Cebollas/crecimiento & desarrollo , Quercetina/análisis , Suelo/análisis , Cebollas/química
17.
J Agric Food Chem ; 55(21): 8444-51, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-17880149

RESUMEN

Baby spinach ( Spinacia oleracea L.) was grown under three types of shade netting (high transmittance, spectrum-altering, and low transmittance) to study the effect on the concentrations of vitamin C (ascorbic acid and dehydroascorbic acid), carotenoids, and chlorophyll and on the visual quality of the leaves. The spinach was sown in April and August and harvested at two growth stages. After harvest, leaves were stored in polypropylene bags at 2 and 10 degrees C. Shading significantly decreased the ascorbic acid concentration of April-sown spinach by 12-33%, but in the August-sown spinach, the response was inconsistent. Concentrations of total carotenoids and total chlorophylls were significantly higher under the nettings in many cases, especially under the spectrum-altering and low-transmittance nettings. Postharvest visual quality and postharvest persistence of the compounds analyzed were not greatly affected by shading. We conclude that these shade nettings are acceptable to use in baby spinach production when it comes to the studied aspects of internal and external quality of the produce.


Asunto(s)
Ácido Ascórbico/análisis , Carotenoides/análisis , Conservación de Alimentos/métodos , Spinacia oleracea/química , Spinacia oleracea/crecimiento & desarrollo , Luz Solar , Clorofila/análisis , Hojas de la Planta/química , Control de Calidad
18.
J Agric Food Chem ; 54(17): 6185-91, 2006 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-16910706

RESUMEN

Variation in quercetin content was investigated in field-cured onions (Allium cepa L.) that had been supplied with different nitrogen fertilizer levels and lifted at different developmental stages. Quercetin content varied significantly between years and was well correlated to global radiation in August. Field curing generally resulted in significant increases in quercetin content compared to levels at lifting. Nitrogen fertilizer level did not affect quercetin content, suggesting that nitrogen leakage from soil may be minimized without effects on flavonol content. Lifting time had minor effects on quercetin content in field-cured onions. Cultivar differences in quercetin content were significant but not consistent in all years. Quercetin content increased significantly less in dark environments compared to field curing, but some quercetin synthesis occurred regardless of light. Field curing with or without foliage still attached did not affect quercetin content, suggesting that no transportation from the foliage to the scales occurred.


Asunto(s)
Agricultura/métodos , Fertilizantes , Nitrógeno/administración & dosificación , Cebollas/química , Quercetina/análisis , Ambiente , Fertilizantes/análisis , Nitrógeno/análisis , Cebollas/crecimiento & desarrollo , Estaciones del Año
19.
J Agric Food Chem ; 54(4): 1248-55, 2006 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-16478244

RESUMEN

The effects of extracts from five cultivars of strawberries on the proliferation of colon cancer cells HT29 and breast cancer cells MCF-7 were investigated, and possible correlations with the levels of several antioxidants were analyzed. In addition, the effects of organic cultivation compared to conventional cultivation on the content of antioxidants in the strawberries and strawberry extracts on the cancer cell proliferation were investigated. The ratio of ascorbate to dehydroascorbate was significantly higher in the organically cultivated strawberries. The strawberry extracts decreased the proliferation of both HT29 cells and MCF-7 cells in a dose-dependent way. The inhibitory effect for the highest concentration of the extracts was in the range of 41-63% (average 53%) inhibition compared to controls for the HT29 cells and 26-56% (average 43%) for MCF-7 cells. The extracts from organically grown strawberries had a higher antiproliferative activity for both cell types at the highest concentration than the conventionally grown, and this might indicate a higher content of secondary metabolites with anticarcinogenic properties in the organically grown strawberries. For HT29 cells, there was a negative correlation at the highest extract concentration between the content of ascorbate or vitamin C and cancer cell proliferation, whereas for MCF-7 cells, a high ratio of ascorbate to dehydroascorbate correlated with a higher inhibition of cell proliferation at the second highest concentration. The significance of the effect of ascorbate on cancer cell proliferation might lie in a synergistic action with other compounds.


Asunto(s)
Antioxidantes/análisis , División Celular/efectos de los fármacos , Alimentos Orgánicos/análisis , Fragaria/química , Frutas/química , Neoplasias/patología , Ácido Ascórbico/análisis , Neoplasias de la Mama , Línea Celular Tumoral , Células HT29 , Humanos
20.
J Agric Food Chem ; 53(24): 9459-64, 2005 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-16302762

RESUMEN

The variation in flavonoid concentration and composition was investigated in baby spinach (Spinacia oleracea L.) cv. Emilia sown on three occasions, each harvested at three growth stages at 6-day intervals. After harvest, leaves were stored in polypropylene bags at 2 or 10 degrees C. Flavonoids were analyzed by reversed phase HPLC. Twelve flavonoid peaks were detected. The main flavonoid, making up on average 43% of the total flavonoid concentration, was identified as 5,3',4'-trihydroxy-3-methoxy-6:7-methylenedioxyflavone-4'-glucuronide. Four other flavonoids each contributed 7-12% of the total flavonoid content. Total flavonoid content was relatively stable during normal retail storage conditions, although some of the individual flavonoid compounds showed considerable variation. The youngest plants had the highest flavonoid concentration, indicating that by harvesting the baby spinach a few days earlier than the current commercial stage of harvest, the flavonoid concentration in the product may be increased and the content of potentially health-promoting compounds enhanced.


Asunto(s)
Flavonoides/análisis , Conservación de Alimentos , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Spinacia oleracea/química , Spinacia oleracea/crecimiento & desarrollo , Estaciones del Año
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