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1.
J Plant Physiol ; 281: 153903, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36608365

RESUMO

To investigate changes in wheat resistance to wheat streak mosaic virus (WSMV) at normal and elevated temperatures and their effects on the emission of volatile organic compounds (VOCs), the profile of these compounds in WSMV-resistant (R) and susceptible (S) wheat cultivars were analyzed. VOCs were discovered in leaves of R and S cultivars inoculated to WSMV at 20 °C and 32 °C at 24, 48 and 72 h post inoculation (hpi) by GC. MS-HS-SPME. Many VOCs and related metabolic pathways of WSMV inoculated and control plants responded differently at low/high temperatures in R/S cultivars. Compounds such as 6-methyl-5-hepten-2-one and heptanal, represented the maximum abundance in R plants compared to S plants at earlier times especially, 48 hpi/20 °C. Also, at 32 °C, VOCs including heptanal and 2-pentenal had the highest increase in abundance at a later time. In addition, in R plants, several pathways were up-regulated commonly at 20 °C and 32 °C. Although, at 20 °C, they were activated at an earlier time. At 32 °C, most of these pathways were up-regulated at 72 hpi. The most important pathways correlated to combined stresses included lipoxygenase, cuticular wax biosynthesis, fatty acid and lipid biosynthesis. The pathway of phenyl ethanol biosynthesis was up-regulated only at 32 °C, which probably is specifically related to resistance to heat stress. Up-regulation of the lipoxygenase pathway appears to increase vector attractiveness and tolerance to biotic and abiotic stresses. Based on these results, is suggested that there is a particular synchronized regulation of defense-related multi-dimensional VOCs emitting network that is necessary for the occurrence of wheat defense responses against WSMV and/or heat. This research highlights the challenge of global warming and the breakdown of plant resistance to viruses which requires metabolic engineering of VOCs for sustainable agriculture.


Assuntos
Compostos Orgânicos Voláteis , Temperatura , Lipoxigenases , Doenças das Plantas
2.
J Agric Food Chem ; 68(8): 2316-2328, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31995376

RESUMO

The climate change is already affecting many agricultural systems and human environments, and the implementation of adaptation strategies, especially those related to irrigated agriculture in semiarid regions, is urgent. In this regard, deep knowledge about the effects that irrigation has on the food quality parameters will allow us to estimate the potential benefits of deficit irrigation (DI) strategies. This work presents the effects on the quality parameters of three almond cultivars (Marta, Guara, and Lauranne) subjected to three irrigation doses: (i) full-irrigated treatment (FI) at 100% crop evapotranspiration (ETC), (ii) an overirrigated treatment at 150% ETC (150% ETC), and (iii) regulated deficit irrigation (RDI65) treatment, in which irrigation was done as in FI, expect during the kernel-filling period when this treatment received 65% ETC. According to experimental findings, the cultivar most sensitive to water stress was Marta, having the most significant improvements for RDI65. In general, the effects of the irrigation dose on the morphological and physicochemical parameters were not huge but some improvements were observed in key parameters such as the color and contents of specific sugars, organic acids, and unsaturated fatty acids. Thus, it can be concluded that the irrigation dose did not drastically affect the fruit almond quality, although it is possible to improve several key parameters when a moderate RDI strategy is applied.


Assuntos
Irrigação Agrícola/métodos , Nozes/química , Prunus dulcis/crescimento & desenvolvimento , Cor , Humanos , Nozes/crescimento & desenvolvimento , Nozes/metabolismo , Prunus dulcis/química , Prunus dulcis/metabolismo , Paladar , Água/análise , Água/metabolismo
3.
Plant Foods Hum Nutr ; 71(4): 375-380, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27423934

RESUMO

None of the health claims about pomegranate juices has been approved yet by European Food Safety Authority (EFSA). There is a general perception among consumers that organic foods are healthier, tastier, and more nutritive than the conventional products. The aim of this research was to study the differences in the biological activity between ready-for-consumption juices obtained from pomegranates fruits grown under conventional and organic agricultural practices. Antioxidant activity has been evaluated by three methods (DPPH•, ABTS+, and FRAP), together with the total contents of phenolics and punicalagin (HPLC-DAD); besides, the Ames test was used to evaluate the antimutagenic potential of the juices. Pomegranate juice, either from conventionally or organically grown fruits, was antimutagenic (mean of 51 and 90 % for Salmonella typhimurium TA100 and TA98, respectively) and it was capable of protecting DNA from both, base-pair or frame-shift type of mutations. In fact, the antimutagenicity of conventional pomegranate juice was higher than that achieved by the organic sample; this finding was linked to a higher punicalagin content (201 and 104 mg L-1 for conventional and organic juices, respectively).


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Sucos de Frutas e Vegetais/análise , Lythraceae/química , Antimutagênicos/análise , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão , Dano ao DNA/efeitos dos fármacos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Polifenóis/análise , Polifenóis/farmacologia
4.
Physiol Res ; 64(4): 583-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26291726

RESUMO

This study has observed possible effect of ellagitannins - compounds from pomegranate on process of steroidogenesis in ovaries. The aim of the study was to investigate the possible effect of punicalagin on secretion of steroid hormones - progesterone, androstenedione, testosterone and 17beta-estradiol by ovarian fragments of rabbits in vitro. Ovarian fragments from sexually mature female New Zealand white rabbits (n=20) were incubated without (control group) or with punicalagin at various doses 1, 10 and 100 microg.ml(-1) for 24 h. Hormones were evaluated by ELISA (The Enzyme-Linked Immunosorbent Assay). Data showed that progesterone and 17beta-estradiol (but not androstenedione and testosterone) release by rabbit ovarian fragments was significantly affected by punicalagin addition at various doses. Punicalagin (at 100 microg.ml(-1)) significantly (P<0.05) increased progesterone secretion. On the other hand, the release of 17beta-estradiol was significantly (P<0.005) decreased by punicalagin addition (at 10 microg.ml(-1)). Our results suggest that punicalagin could have dose-dependent impact on secretion of steroid hormones progesterone and 17beta-estradiol by rabbit ovarian fragments and it may be effector in process of ovarian steroidogenesis.


Assuntos
Hormônios Esteroides Gonadais/biossíntese , Taninos Hidrolisáveis/administração & dosagem , Lythraceae/química , Ovário/metabolismo , Animais , Relação Dose-Resposta a Droga , Feminino , Ovário/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Coelhos
5.
Environ Monit Assess ; 187(6): 387, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26022848

RESUMO

Several agricultural fields show high contents of arsenic because of irrigation with arsenic-contaminated groundwater. Vegetables accumulate arsenic in their edible parts when grown in contaminated soils. Polluted vegetables are one of the main sources of arsenic in the food chain, especially for people living in rural arsenic endemic villages of India and Bangladesh. The aim of this study was to assess the feasibility of floriculture in the crop rotation system of arsenic endemic areas of the Bengal Delta. The effects of different arsenic concentrations (0, 0.5, 1.0, and 2.0 mg As L(-1)) and types of flowering plant (Gomphrena globosa and Zinnia elegans) on plant growth and arsenic accumulation were studied under hydroponic conditions. Total arsenic was quantified using atomic absorption spectrometer with hydride generation (HG-AAS). Arsenic was mainly accumulated in the roots (72 %), followed by leaves (12 %), stems (10 %), and flowers (<1 %). The flowering plants studied did not show as high phytoremediation capacities as other wild species, such as ferns. However, they behaved as arsenic tolerant plants and grew and bloomed well, without showing any phytotoxic signs. This study proves that floriculture could be included within the crop rotation system in arsenic-contaminated agricultural soils, in order to improve food safety and also food security by increasing farmer's revenue.


Assuntos
Arsênio/análise , Gleiquênias/fisiologia , Hidroponia , Poluentes do Solo/análise , Agricultura , Arsênio/metabolismo , Bangladesh , Biodegradação Ambiental , Monitoramento Ambiental , Índia , Folhas de Planta/química , Raízes de Plantas/química , Solo/química , Poluentes do Solo/metabolismo , Espectrofotometria Atômica , Verduras
6.
Food Sci Technol Int ; 21(6): 454-66, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25028154

RESUMO

A cross-cultural study was conducted with Spanish and US consumers to gain an insight into the preferred characteristics of olive oils in both countries. Six commercial olive oils (four samples from Spain and two samples from the US) were analyzed by a highly trained panel (descriptive analysis) and also by two consumers' groups (100 consumers from Spain and 100 from the US). Demographic, acceptability, and Just-About-Right data were collected to study the preferences of both groups, and the relationships with descriptive data were explored to determine the drivers of like/dislike. The Spanish extra virgin olive oils and the imported US extra virgin olive oil were characterized by having bitter, pungent, and more green notes, and were preferred by the Spanish consumers. The US consumers liked the bland Spanish refined olive oil, and the Californian olive oil that was characterized by fruity, floral, and sweet notes. The results showed that the Spanish consumers were more aware about olive oil quality in general than their US counterparts, maybe because of a higher usage of the product in Spain. The present study provides essential data which might help producers in designing and promoting olive oils matching US consumers' requirements, an emerging market for this Mediterranean product.


Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Preferências Alimentares , Óleos de Plantas , Paladar , Adolescente , Adulto , Idoso , Cor , Comparação Transcultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Análise de Componente Principal , Microextração em Fase Sólida , Espanha , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
7.
Neotrop Entomol ; 42(1): 89-94, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23949717

RESUMO

The essential oil of Callistemon citrinus (Curtis) leaves was extracted by hydro distillation and tested on female and male adults of Callosobruchus macullatus (F.) for insecticidal and repellent effects. GC-MS analysis was used to identify and quantify the volatile composition of the essential oil. Results showed that 1,8-cineole (34.2%) and α-pinene (29.0%) were the major components of the oil. Callistemon citrinus oil was found to be toxic to adult insects when applied by fumigation. Responses varied according to the gender of the insect and exposure time. LC50 values were 12.88 and 84.4 µL. L(-1) for males and females, respectively. An increase in exposure time from 3 to 24 h caused an increase in mortality from 50% to 100% in males and from 15.5% to 85.2% in females, at the highest concentration (500 µL. L(-1)). The essential oil also had a repellent effect against C. macullatus in a filter paper arena test. After 2 and 4 h, 86% and 94%, respectively, repellent effects were demonstrated at the highest concentration of 0.4 µL .cm(-2). These observations suggest that C. citrinus essential oil may be usefully applied to control storage pests.


Assuntos
Besouros/efeitos dos fármacos , Repelentes de Insetos , Inseticidas , Myrtaceae , Óleos Voláteis/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Óleos Voláteis/química
8.
Meat Sci ; 93(1): 61-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22910805

RESUMO

A consumer study was conducted to determine the most popular beef seasonings used in three countries: Argentina, United States (US), and Spain. Once the typical cooking methods and seasonings in these countries were established, descriptive analysis was used to determine the differences in the main flavor attributes, particularly the impact on beef characteristics, of the samples. Large variations were found in the consumer practices in the studied countries, and the preferred seasonings from each country were identified. This study showed that on average US consumers would prefer beef products with more initial flavor impact, brown/roasted and salty characteristics than Argentinian or Spanish consumers. The addition of seasonings changed some of the main beef attributes, but the changes were dependent on the cooking method. Beef identity (Beef ID), brown/roasted, and bloody/serumy were the attributes most affected when adding different seasonings.


Assuntos
Comportamento do Consumidor , Aromatizantes , Carne/análise , Paladar , Animais , Argentina , Sangue , Bovinos , Cor , Culinária , Humanos , Espanha , Estados Unidos
9.
Food Sci Technol Int ; 18(2): 129-38, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22414932

RESUMO

Commercial juices of sweet pomegranates and fresh juices of sour-sweet pomegranates were analysed for organic acids, sugars, antioxidant activity, volatile composition, sensory profile and consumer liking. Organic acids and sugars were analysed by high-performance liquid chromatography, while volatiles were extracted using hydrodistillation and analysed by gas chromatography-mass spectrometry and gas chromatography-flame ionisation detector. Malic acid was predominant in sweet juices while citric acid in sour-sweet samples. Fructose and glucose were found as the predominant sugars in all juices. A total of 18 compounds were found in pomegranate aroma profile, including monoterpenes, aldehydes, alcohols, monoterpenoids and linear hydrocarbons; the most abundant compounds were 3-carene, α-terpinene and α-terpineol. The total concentration of volatiles ranged from 2.0 up to 5.1 mg/L, with commercial samples presenting higher total concentrations due to the presence of peel volatiles. The high potential of sour-sweet pomegranate fruits for the juice industry was supported by (a) the high values of positive attributes, such as colour and fresh pomegranate flavour and (b) the high overall liking of consumers.


Assuntos
Bebidas , Indústria Alimentícia , Lythraceae , Antioxidantes/química , Análise de Alimentos , Lythraceae/química , Espanha , Compostos Orgânicos Voláteis/química
10.
Food Sci Technol Int ; 17(3): 241-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21652767

RESUMO

The effects of organic farming on antioxidant activity, CIE L*a*b* color, carotenoids composition, minerals contents, vitamin C and sensory quality of Orogrande mandarin juices were studied. Independent of the farming type, mandarin juices can be considered as good source of some important nutrients, such as potassium and antioxidant chemicals, for example, ß-cryptoxanthin. Organic farming of mandarin resulted in juices with higher antioxidant activity, total carotenoids concentrations, minerals (Ca, K and Fe) contents, vitamin C content, more appealing and intense orange color and better sensory quality. For instance, organic Orogrande juice contained significantly (p < 0.001) higher total carotenoids content (22.7 ± 0.3 mg/L) than conventional juice (15.7 ± 0.4 mg/L); a similar pattern was observed for the antioxidant activity, with values being 0.076±0.004 and 0.053 ± 0.003 mM Trolox m/L in organic and conventional juices, respectively. A trained panel stated that organic Orogrande juices had higher intensities of orange color, fresh mandarin and floral aromas than conventional juices.


Assuntos
Antioxidantes/química , Ácido Ascórbico/química , Bebidas/análise , Carotenoides/química , Citrus , Minerais/química , Cor , Comportamento do Consumidor , Frutas , Humanos
11.
Environ Pollut ; 157(12): 3351-3, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19819054

RESUMO

This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 microg L(-1). The plant produces no sludge and the operation cost is 1.0 US$ per day for producing 2000 L of potable water.


Assuntos
Arsênio/química , Filtração/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Abastecimento de Água/análise , Adsorção , Água Subterrânea/química , Índia , Oxirredução
12.
J Agric Food Chem ; 56(20): 9469-74, 2008 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-18800809

RESUMO

Arsenic (As) species were quantified by HPLC-HG-AFS in water and vegetables from a rural area of West Bengal (India). Inorganic species predominated in vegetables (including rice) and drinking water; in fact, inorganic arsenic (i-As) represented more than 80% of the total arsenic (t-As) content. To evaluate i-As intake in an arsenic affected rural village, a food survey was carried out on 129 people (69 men and 60 women). The data from the survey showed that the basic diet, of this rural population, was mainly rice and vegetables, representing more than 50% of their total daily food intake. During the periods when nonvegetarian foods (fish and meat) were scarce, the importance of rice increased, and rice alone represented more than 70% of the total daily food intake. The food analysis and the food questionnaires administrated led us to establish a daily intake of i-As of about 170 microg i-As day (-1), which was above the tolerable daily intake of 150 microg i-As day (-1), generally admitted. Our results clearly demonstrated that food is a very important source of i-As and that this source should never be forgotten in populations depending heavily on vegetables (mainly rice) for their diet.


Assuntos
Arsênio/análise , Arsenicais/análise , Ingestão de Alimentos , Contaminação de Alimentos/análise , Oryza/química , População Rural/estatística & dados numéricos , Verduras/química , Adolescente , Adulto , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Poluentes Químicos da Água/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-17852383

RESUMO

Arsenic contamination of rice plants by arsenic-polluted irrigation groundwater could result in high arsenic concentrations in cooked rice. The main objective of the study was to estimate the total and inorganic arsenic intakes in a rural population of West Bengal, India, through both drinking water and cooked rice. Simulated cooking of rice with different levels of arsenic species in the cooking water was carried out. The presence of arsenic in the cooking water was provided by four arsenic species (arsenite, arsenate, methylarsonate or dimethylarsinate) and at three total arsenic concentrations (50, 250 or 500 microg l(-1)). The results show that the arsenic concentration in cooked rice is always higher than that in raw rice and range from 227 to 1642 microg kg(-1). The cooking process did not change the arsenic speciation in rice. Cooked rice contributed a mean of 41% to the daily intake of inorganic arsenic. The daily inorganic arsenic intakes for water plus rice were 229, 1024 and 2000 microg day(-1) for initial arsenic concentrations in the cooking water of 50, 250 and 500 microg arsenic l(-1), respectively, compared with the tolerable daily intake which is 150 microg day(-1).


Assuntos
Arsênio/análise , Arsenicais/análise , Contaminação de Alimentos/análise , Oryza/química , Poluentes Químicos da Água/análise , Análise de Variância , Arsênio/administração & dosagem , Arsênio/toxicidade , Arsenicais/administração & dosagem , Culinária/métodos , Dieta , Exposição Ambiental , Humanos , Índia , Saúde da População Rural , Poluentes Químicos da Água/administração & dosagem , Abastecimento de Água/análise
14.
Artigo em Inglês | MEDLINE | ID: mdl-19680842

RESUMO

Arsenic (As) contamination of rice plants can result in high total As concentrations (t-As) in cooked rice, especially if As-contaminated water is used for cooking. This study examines two variables: (1) the cooking method (water volume and inclusion of a washing step); and (2) the rice type (atab and boiled). Cooking water and raw atab and boiled rice contained 40 microg As l(-1) and 185 and 315 microg As kg(-1), respectively. In general, all cooking methods increased t-As from the levels in raw rice; however, raw boiled rice decreased its t-As by 12.7% when cooked by the traditional method, but increased by 15.9% or 23.5% when cooked by the intermediate or contemporary methods, respectively. Based on the best possible scenario (the traditional cooking method leading to the lowest level of contamination, and the atab rice type with the lowest As content), t-As daily intake was estimated to be 328 microg, which was twice the tolerable daily intake of 150 microg.


Assuntos
Arsênio/análise , Culinária/métodos , Contaminação de Alimentos/análise , Oryza/química , Exposição Ambiental/análise , Análise de Alimentos/métodos , Análise de Alimentos/normas , Humanos , Índia , Garantia da Qualidade dos Cuidados de Saúde , Saúde da População Rural/estatística & dados numéricos
15.
J Agric Food Chem ; 50(13): 3738-42, 2002 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-12059152

RESUMO

The Spaniard legislation sets up maximum levels for total arsenic (As) and copper (Cu) in confectionery products at 0.1 and 5.0 microg g(-)(1), respectively. Concentrations of these two trace elements were determined in four confectionery products: chewing gum, two licorice items, and soft candy. The effects of raw materials quality and production lines were studied. Arsenic and copper were quantified by atomic absorption spectrometry with hydride generation and slotted-tube atom trap tubes, respectively. Their levels were, in general, below the maximum limits establish by the Spaniard legislation; however, the As concentration in the licorice sticks was above this maximum limit (0.11 +/- 0.01 microg g(-)(1)). Statistics proved that quality of raw materials and the production lines both significantly affected As and Cu concentrations in the final products. The licorice extract and molasses were found as the common source for As and Cu pollution. The As concentration in the licorice extract was 0.503 +/- 0.01 microg g(-)(1), and could represent a serious hazard to human health if it is used in high proportions.


Assuntos
Arsênio/análise , Doces/análise , Cobre/análise , Manipulação de Alimentos/métodos , Glycyrrhiza/química , Legislação sobre Alimentos , Controle de Qualidade , Espanha , Espectrofotometria Atômica
16.
Food Addit Contam ; 19(5): 417-26, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12028641

RESUMO

The main objective was to evaluate whether arsenic accumulated in the edible pods and seeds of Phaseolus vulgaris, cv. F15 above the Spanish maximum recommended concentration for food crops, 1 mg kg(-1) on a fresh weight basis. Only organic arsenicals, methylarsonic and dimethylarsinic acids were used because they were: (1) the only arsenic species allowed for agricultural applications and (2) more mobile than inorganic species. Selection of French beans, a sensitive plant to arsenic, was based on the fact that arsenic-upward translocation is higher in sensitive than in tolerant plants. A 2 x 3 factorial experiment was conducted with two organic arsenic species (methylarsonic acid, dimethylarsinic acid) and three arsenic concentrations (0.2, 0.5, 1.0 mg l(-1)). Experimental results showed that the low bean plant tolerance to arsenic was possibly due to the high arsenic-upward transport to shoots, which could result in profound negative metabolic consequences. Even under extreme adverse conditions, arsenic residues in edible beans were below the maximum statutory limit set by the Spanish legislation. It is concluded that the major drawback of organic arsenical herbicides is that of decreased productivity rather than high arsenic intake by consumers of edible products from sensitive plant species.


Assuntos
Arsenicais/análise , Ácido Cacodílico/análise , Contaminação de Alimentos/análise , Herbicidas/análise , Phaseolus/química , Verduras/química , Arsenicais/farmacocinética , Ácido Cacodílico/farmacocinética , Ácido Cacodílico/toxicidade , Herbicidas/farmacocinética , Herbicidas/toxicidade , Humanos , Phaseolus/efeitos dos fármacos , Phaseolus/crescimento & desenvolvimento , Controle de Qualidade , Verduras/efeitos dos fármacos , Verduras/crescimento & desenvolvimento
17.
J Environ Sci Health B ; 36(6): 849-61, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11757743

RESUMO

The main objective of this study was to evaluate whether arsenic accumulated in the edible pods and seeds of Phaseolus vulgaris, cv. Helda, above the Spanish maximum recommended concentration for food crops, 1 mg kg(-1) on a fresh weight basis. Only organic arsenicals were used because they are: a) the only arsenic species allowed for agricultural applications and b) more mobile than inorganic species. Selection of French beans, a sensitive plant to arsenic, was based on the fact that arsenic upward translocation is higher in sensitive than in tolerant plants. A 2 x 3 factorial experiment was conducted with two organic arsenic species: methylarsonic acid (MAA) or dimethylarsinic acid (DMAA) and three arsenic concentrations: 0.2, 0.5, or 1.0 mg L(-1). Arsenic phytotoxicity was primarily determined by soluble arsenic concentration. Experimental results showed that the low bean plant tolerance to arsenic is possibly due to the high arsenic upward transport to shoots, which could result in profound negative metabolic consequences. Even under extremely adverse conditions, arsenic residues in edible beans were below the maximum statutory limit set by the Spanish legislation. It can be concluded that the major danger of organic arsenical herbicides is that of decreased productivity rather than high arsenic uptake by consumers.


Assuntos
Arsênio/metabolismo , Phaseolus/metabolismo , Animais , Arsênio/toxicidade , Relação Dose-Resposta a Droga , Contaminação de Alimentos , Frutas/metabolismo , Humanos , Luz , Phaseolus/crescimento & desenvolvimento , Plantas Comestíveis/crescimento & desenvolvimento , Plantas Comestíveis/metabolismo , Sementes/metabolismo , Distribuição Tecidual
18.
J Agric Food Chem ; 47(3): 1247-53, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10552445

RESUMO

The uptake of arsenic (As) species by Lycopersicum esculentum, growing under soilless culture conditions, was studied. A 4 x 3 x 2 factorial experiment was conducted with four As species (arsenite, arsenate, methylarsonate, and dimethylarsinate), three As concentrations (1, 2, and 5 mg L(-)(1)) and two tomato cultivars (Marmande and Muchamiel). The phytoavailability and phytotoxicity were primarily determined by the As species. The concentrations of As in plant increased significantly with increasing As concentration in solution. Both MA and DMA showed a higher upward translocation than arsenite and arsenate, and treatments with MA and DMA clearly reduced plant growth and fruit yield. The As concentration in tomatoes treated with arsenite or arsenate were within the range considered normal in food crops; however, the As concentration in tomatoes treated with MA and DMA were close to or even above the maximum limit. When tomato plants are exposed to high concentrations of As in nutrient solutions, they may uptake As to concentrations unacceptable for human food.


Assuntos
Arsênio/metabolismo , Solanum lycopersicum/metabolismo , Arseniatos/metabolismo , Arsenicais/metabolismo , Arsenitos/metabolismo , Ácido Cacodílico/metabolismo , Hidroponia , Solanum lycopersicum/crescimento & desenvolvimento
19.
J Environ Sci Health B ; 34(4): 661-79, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10390853

RESUMO

Arsenic (As) uptake by Rhapanus sativus L. (radish), cv. Nueva Orleans, growing in soil-less culture conditions was studied in relation to the chemical form and concentration of As. A 4 x 3 factorial experiment was conducted with treatments consisting of four As chemical forms [As(III), As(V), MMAA, DMAA] and three As concentrations (1.0, 2.0, and 5.0 mg As L-1). None of the As treatments were clearly phytotoxic to this radish cultivar. Arsenic phytoavailability was primarily determined by the As chemical form present in the nutrient solution and followed the trend DMAA < or = As(V) < or = As(III) << MMAA. Root and shoot As concentrations significantly increased with increasing As application rates. Monomethyl arsonic acid treatments caused the highest As accumulation in both roots and shoots, and this organic arsenical showed a higher uptake rate than the other As compounds. Inner root As concentrations were, in general, within the normal range for As contents in food crops but root skin As levels were close or above the maximum threshold set for As content in edible fruit, crops and vegetables. The statement that toxicity limits plant As uptake to safe levels was not confirmed in our study. If radish plants are exposed to a large pulse of As, as growth on contaminated nutrient solutions, they may accumulate residues which are unacceptable for animal and human consumption without exhibiting symptoms of phytotoxicity.


Assuntos
Arsênio/toxicidade , Poluentes do Solo/toxicidade , Verduras/química , Arsênio/farmacocinética , Relação Dose-Resposta a Droga , Poluentes do Solo/farmacocinética , Distribuição Tecidual
20.
J Agric Food Chem ; 47(6): 2288-94, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10794624

RESUMO

Arsenic (As) uptake by turnip, growing under soilless culture conditions, was studied. A 4 x 3 factorial experiment was conducted with four As species [arsenite, arsenate, methylarsonic acid (MMAA), dimethylarsinic acid (DMAA)] and three As concentrations (1.0, 2.0, and 5.0 mg L(-)(1)). Arsenic phytoavailability and phytotoxicity were primarily determined by As speciation. Organic arsenicals, especially MMAA, were clearly phytotoxic to this turnip cultivar. Plant As concentrations significantly increased with increasing As application rates. Both organic arsenicals showed a higher upward translocation than their inorganic counterparts, contributing to the greater phytotoxicity and lower dry matter productions of these organic treatments. Both inner root and outer root skin As concentrations were above the maximum limit set for As content in food crops (1.0 mg kg(-)(1)). If turnip plants are exposed to a large pulse of As, as growth on contaminated nutrient solutions, they will accumulate residues at levels that are unacceptable for animal and human consumption.


Assuntos
Arsênio/metabolismo , Arsênio/toxicidade , Arsenicais/análise , Brassica/metabolismo , Contaminação de Alimentos , Animais , Humanos
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