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1.
PLoS One ; 15(12): e0235028, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362256

RESUMO

Cyclocephalini beetles of the genus Cyclocephala (Coleoptera: Melolonthidae: Dynastinae) use flowers of some plants as food, shelter, and mating sites. However, little is known about floral scent chemistry involved in this interaction. Here we show that a sesquiterpene alcohol mediates attraction of Cyclocephala paraguayensis Arrow, on bottle gourd flowers, Lagenaria siceraria (Cucurbitaceae). Both males and females started to aggregate on the flowers at twilight; after that, mating began and remained for the entire night. GC-FID/EAD analysis of the L. siceraria floral scent collected in the field revealed that only the major constituent of the airborne volatiles elicited electroantennographic responses on male and female antennae of C. paraguayensis. This compound was identified as (3S,6E)-nerolidol, which was tested in two field trapping trials in Brazil. In the first bioassay, traps baited with nerolidol (mix of isomers) captured significantly more adult C. paraguayensis than control traps. In the second field trial, catches in traps baited with a mixture of isomers or enantiopure nerolidol were significantly higher than captures in control traps, but the treatments did not differ significantly. Analysis from the gut content of adult C. paraguayensis showed the presence of pollen, suggesting that they also use bottle gourd flowers for their nourishment. Taken together, these results suggest that (3S,6E)-nerolidol plays an essential role in the reproductive behavior of C. paraguayensis by eliciting aggregation, mating, and feeding.


Assuntos
Besouros/fisiologia , Cucurbita/metabolismo , Sesquiterpenos/metabolismo , Animais , Brasil , Besouros/metabolismo , Cucurbita/fisiologia , Cucurbitaceae/metabolismo , Cucurbitaceae/fisiologia , Feminino , Flores/fisiologia , Masculino , Odorantes/análise , Feromônios/análise , Pólen/fisiologia , Polinização , Sesquiterpenos/análise
2.
PLoS One ; 15(6): e0230546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32516347

RESUMO

Winter squash fruits (Cucurbita moschata D.) are among the best sources of vitamin A precursors and constitute sources of bioactive components such as phenolic compounds and flavonoids. Approximately 70% of C. moschata seed oil is made up of unsaturated fatty acids, with high levels of monounsaturated fatty acids and components such as vitamin E and carotenoids, which represent a promising nutritional aspect in the production of this vegetable. C. moschata germplasm expresses high genetic variability, especially in Brazil. We assessed 91 C. moschata accessions, from different regions of Brazil, and maintained at the Federal University of Viçosa (UFV) Vegetable Germplasm Bank, to identify early-flowering accessions with high levels of carotenoids in the fruit pulp and high yields of seed and seed oil. Results showed that the accessions have high variability in the number and mass of seeds per fruit, number of accumulated degree-days for flowering, total carotenoid content, and fruit productivity, which allowed selection for considerable gains in these characteristics. Analysis of the correlation between these characteristics provided information that will assist in selection to improve this crop. Cluster analysis resulted in the formation of 16 groups, confirming the variability of the accessions. Per se analysis identified accessions BGH-6749, BGH-5639, and BGH-219 as those with the earliest flowering. Accessions BGH-5455A and BGH-5598A had the highest carotenoid content, with averages greater than 170.00 µg g-1 of fresh mass. With a productivity of 0.13 t ha-1, accessions BGH-5485A, BGH-4610A, and BGH-5472A were the most promising for seed oil production. These last two accessions corresponded to those with higher seed productivity, averaging 0.58 and 0.54 t ha-1, respectively. This study confirms the high potential of this germplasm for use in breeding for promotion of earlier flowering and increase in total content of fruit pulp carotenoids and in seed and seed oil productivity.


Assuntos
Agricultura , Cucurbita/anatomia & histologia , Cucurbita/genética , Variação Genética , Genótipo , Carotenoides/metabolismo , Cucurbita/metabolismo , Frutas/metabolismo
3.
Plant Physiol Biochem ; 151: 673-680, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32353673

RESUMO

This study was carried out to evaluate the effects of foliar sprays containing boron (B) nano-fertilizer (NF) on the growth and physiology of lettuce (Lactuca sativa) and zucchini (Cucurbita pepo). Plants were grown under greenhouse conditions for 60 days on a modified Hoagland solution with the presence and absence of boron (+B or -B). A synthesized B-NF foliar spray and a commercial B foliar fertilizer (Bortrac™ 150, BT) was applied at a concentration of 30 mg B L-1 at 10-d intervals throughout the experiment. The B-NF treatment increased the growth of lettuce 2.7- and 1.9-fold for shoots and roots, respectively, with an average production of lettuce biomass by ~58%. Similarly, the NF increased the growth of zucchini by 18 and 66% compared with Control-B (the absence of B), and 13 and 36% compared with BT, both for shoots and roots, respectively. Nevertheless, NF + B mostly decreased lettuce growth with symptoms of B toxicity in leaves. In lettuce, addition of B did not affect concentrations of phenols; however, in zucchini, Control-B induced a higher production of phenolic compounds possibly related to B deficiency. The B addition in lettuce reduced the DPPH activity by 32 and 21% in NF and BT, respectively, compared to Control-B. These responses were similar in zucchini; however, the effect of B was product of its presence in mineral solution rather than due the foliar product applied. This suggests that a NF-based delivery system for B may be highly effective at boosting plant productivity on B-limited soils.


Assuntos
Boratos , Compostos de Cálcio , Cucurbita , Fertilizantes , Alface , Nanopartículas , Boratos/química , Compostos de Cálcio/química , Cucurbita/metabolismo , Alface/metabolismo , Nanopartículas/química , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo
4.
PLoS One ; 15(5): e0232554, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374758

RESUMO

Recycled paper has the potential to be used as a mulch for vegetable production and can be adopted for the cultivation of Italian zucchini. However, there have been no studies about the water savings or crop coefficient values used in irrigation management in this system; therefore, there is a need for more research. In view of the above, this study aimed to evaluate the effects of recycled paper mulch on evaporation and evapotranspiration in Italian zucchini and to determine the crop coefficients in its developmental stages. The study was carried out in two cultivation cycles conducted at the Lysimetric Station in Viçosa, MG, Brazil. The experiments were installed in a randomized block design with four replicates. Four lysimeter cultivation treatments were applied: without mulch (C); with recycled paper as mulch (CP); with only recycled paper (P); and with Bahia grass (G). Irrigation and drainage measurements were performed daily to calculate the crop and reference evapotranspiration, and thus the crop coefficient (Kc) values. The following characteristics were evaluated: fruit yield, NDVI and water productivity. For the cultivation of Italian zucchini using paper as mulch, Kc values of 0.54, 0.77 and 0.44 and Kcb values of 0.15, 0.45 and 0.18 are recommended for the initial, intermediate and final stages, respectively. NDVI can be used to estimate the Kc values for Italian zucchini. The use of recycled paper as mulch reduces the water consumption of Italian zucchini.


Assuntos
Produção Agrícola/métodos , Cucurbita/crescimento & desenvolvimento , Verduras/crescimento & desenvolvimento , Irrigação Agrícola , Brasil , Cucurbita/metabolismo , Itália , Papel , Transpiração Vegetal , Reciclagem , Solo , Verduras/metabolismo , Água
5.
Biochimie ; 170: 118-127, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935442

RESUMO

Apart from being a conduit for photoassimilate transport in plants, the phloem serves as a pathway for transport of proteins and RNAs from sites of their synthesis to distant plant parts. As demonstrated for mRNAs and small RNAs such as miRNA and siRNA, their phloem transport is largely involved in responses to environmental cues including stresses and pathogen attacks. RNA molecules are believed to be transported in the phloem in the form of complexes with RNA-binding proteins; however, proteins forming such complexes are generally poorly studied. Here, we demonstrate that the Cucurbita maxima phloem serpin-1 (CmPS1), which has been previously described as a functional protease inhibitor capable of long-distance transport via the phloem, is able to bind RNA in vitro. Among different RNAs tested, CmPS1 exhibits a preference for imperfect RNA duplexes and the highest affinity to tRNA. A characteristic complex formed by CmPS1 with tRNA is not observed upon CmPS1 binding to tRNA-like structures of plant viruses. Mutational analysis demonstrates that the CmPS1 N-terminal region is not involved in RNA binding. Since antithrombin-III, the human protease inhibitor of serpin family most closely sequence-related to CmPS1, is found to be unable to bind RNA, one can suggest that, in its evolution, CmPS1 has gained the RNA binding capability as an additional function likely relevant to its specific activities in the plant phloem.


Assuntos
MicroRNAs/metabolismo , Proteínas de Plantas/metabolismo , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , RNA de Transferência/metabolismo , Proteínas de Ligação a RNA/metabolismo , Serpinas/metabolismo , Sequência de Aminoácidos , Cucurbita/metabolismo , Técnicas In Vitro , MicroRNAs/genética , Proteínas de Plantas/genética , RNA Mensageiro/genética , RNA de Plantas/genética , RNA de Transferência/genética , Proteínas de Ligação a RNA/genética , Homologia de Sequência , Serpinas/genética
6.
Mol Plant ; 13(2): 321-335, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31812689

RESUMO

In plants, RNA interference (RNAi) plays a pivotal role in growth and development, and responses to environmental inputs, including pathogen attack. The intercellular and systemic trafficking of small interfering RNA (siRNA)/microRNA (miRNA) is a central component in this regulatory pathway. Currently, little is known with regards to the molecular agents involved in the movement of these si/miRNAs. To address this situation, we employed a biochemical approach to identify and characterize a conserved SMALL RNA-BINDING PROTEIN 1 (SRBP1) family that mediates non-cell-autonomous small RNA (sRNA) trafficking. In Arabidopsis, AtSRBP1 is a glycine-rich (GR) RNA-binding protein, also known as AtGRP7, which we show binds single-stranded siRNA. A viral vector, Zucchini yellow mosaic virus (ZYMV), was employed to functionally characterized the AtSRBP1-4 (AtGRP7/2/4/8) RNA recognition motif and GR domains. Cellular-based studies revealed the GR domain as being necessary and sufficient for SRBP1 cell-to-cell movement. Taken together, our findings provide a foundation for future research into the mechanism and function of mobile sRNA signaling agents in plants.


Assuntos
Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cucurbita/genética , Cucurbita/metabolismo , Cucurbita/virologia , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Potyvirus/genética , Potyvirus/fisiologia , Domínios Proteicos , Motivo de Reconhecimento de RNA , RNA de Plantas/metabolismo , RNA Viral/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética
7.
J Photochem Photobiol B ; 200: 111650, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31698288

RESUMO

The biosynthesis of ZnO nanoparticles was synthesized by biogenic reduction of applied Cucurbita seed extract. The powder X-ray diffraction pattern displayed the high crystalline nature of synthesized ZnO nanoparticles and the crystallite size was calculated at 35 nm range. The Fourier Transform Infra-Red study revealed the functional groups of biogenic reduction and vibrational bands present in the synthesized nanoparticles. The UV-Visible analysis explained the SPR absorption peak at 371 nm. The Photoluminescence study revealed the strong red shoulder emission peak at 665 nm. The particle size analyzer displayed the particle size occupies majorly on 45-65 nm. The SEM analysis pointed the ZnO nanoparticles under rod, rectangular and hexagonal shapes were procured. The EDAX spectrum also mapping exposed the purity of formed ZnO nanoparticles with just Zn and O peaks. The HRTEM analysis exposed the hexagonal shape wurtzite structure ZnO particles formation. The physiochemical analysis revealed general nature of Cucurbita seed powder moreover which explained the phytochemicals involved in biogenic reduction of ZnO nanoparticles. The formed ZnO nanoparticles exhibited good antibacterial activity on E. coli, Bacillus pumilus, and Salmonella typhi bacteria. The cytotoxicity study stated the good toxicity on E. coli AB 1157. The antifungal activity showed a better effect on Aspergillus flavus and Aspergillus niger fungi. The antioxidant activity clarified the good free radical scavenging action. The anti larvicidal activity expressed a better impact on Culex tritaeniorhynchus mosquito larvae.


Assuntos
Cucurbita/química , Culex/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química , Óxido de Zinco/química , Animais , Antibacterianos/biossíntese , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Cucurbita/metabolismo , Culex/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Química Verde , Larva/efeitos dos fármacos , Nanopartículas Metálicas/química , Tamanho da Partícula , Sementes/química , Sementes/metabolismo
8.
J Food Biochem ; 43(11): e13037, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31502274

RESUMO

Pumpkin seeds are often used in traditional medicine in the management of erectile dysfunction. However, there is insufficient information about the possible biochemical rationale behind this practice. Hence, this study investigated the influence of fluted pumpkin seed on critical enzymes involved in erectile function in isolated rats' corpus cavernosum in vitro. The phenolics and amino acid contents of fluted pumpkin seed were determined using HPLC-DAD and GC-PFPD analyses respectively. The aqueous extract of the fluted pumpkin seed significantly (p < .05) scavenged free radicals and inhibited PDE-5, arginase, AChE, and ACE in rats' corpus cavernosum in a concentration-dependent pattern. Quercitrin and luteolin were the most dominant phenolics, while arginine, aspartate, and cysteine were the most aboundant amino acid constituents. The positive modulatory effect of the fluted pumpkin seed on these critical markers of erectile function could be attributed to its polyphenolics and amino acid constituents. PRACTICAL APPLICATIONS: This study brought to limelight the medicinal importance of fluted pumpkin seed in erectile functions. Therefore, this seed could be used as a functional food ingredient in the management of erectile dysfunctions and also in improving erectile functions in men. In addition, the dominant phenolics and amino acid constituents of this seed might be an effective nutraceutical in enhancing erections in men.


Assuntos
Aminoácidos/metabolismo , Cucurbita/metabolismo , Disfunção Erétil/dietoterapia , Extratos Vegetais/metabolismo , Polifenóis/metabolismo , Aminoácidos/análise , Animais , Cucurbita/química , Disfunção Erétil/metabolismo , Disfunção Erétil/fisiopatologia , Humanos , Masculino , Ereção Peniana , Pênis/fisiopatologia , Extratos Vegetais/análise , Polifenóis/análise , Ratos , Sementes/química
9.
Molecules ; 24(16)2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31416184

RESUMO

Plants and animals are sources of various bioactive compounds that exhibit a broad spectrum of health-promoting effects. Scientists continue studies on the chemical composition of many products in search of foods with high nutritional value. The pumpkin (Cucurbita sp.) is unquestionably a source of valuable nutrients. This vegetable is well-known all over the world and it is appreciated due to its high content of carotenoids, but it is still not much used in the processing industry. The aim of present study was to compare the flesh of 15 pumpkin varieties belonging to the Cucurbita pepo and C. moschata species in terms of the bioactive compound content (carotenoids, phenolic acids, flavonols, minerals and vitamins) and to demonstrate whether the variety has an effect on the chemical composition. To date, no such extensive research has been carried out in this area. The research revealed that the pumpkin pulp had high content of carotenoids. In nearly all cases lutein was the most abundant carotenoid. Numerous phenolic acids and flavonols were also identified. All the cultivars contained gallic acid, protocatechuic acid, 4-hydroxybenzoic acid, vanillic acid, chlorogenic acid, caffeic acid, and rutin. The pumpkin pulp also contained alpha- and gamma-tocopherol. No beta- or delta-tocopherol was found. Potassium, calcium, and sodium were the most abundant minerals. The research also proved that the profile of bioactive compounds in the pumpkin pulp was considerably diversified and depended on the species and cultivar.


Assuntos
Cucurbita/química , Metaboloma , Metabolômica , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/farmacologia , Carotenoides/química , Carotenoides/farmacologia , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Cucurbita/metabolismo , Metabolômica/métodos , Minerais/análise , Valor Nutritivo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Polifenóis/química , Polifenóis/farmacologia , Metabolismo Secundário
10.
J Sci Food Agric ; 99(15): 6768-6777, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31353471

RESUMO

BACKGROUND: Portable handheld near infrared spectroscopy (NIRS) instruments currently present enormous advantages in terms of size, weight, and robustness. They also provide fast, precise information that can be obtained in situ, and they represent a viable option for controlling vegetable safety and quality during the growth period. The aim of this research was to evaluate three handheld portable NIRS instruments for in situ and real-time analysis of intact summer squashes. Traditional methods were used to analyze 221 summer squashes, and this work was used to develop calibration models for morphological, safety, and quality parameters. The longitudinal distribution of nitrate content in summer squashes weighing over 400 g was also studied, and the evolution of this parameter during the harvest period was tracked to determine which summer squashes and which zones of the vegetables (peduncle, equatorial, or stylar) could be earmarked for baby-food production. RESULTS: The robustness of the calibration models confirmed the expectations raised by NIRS technology for morphological, safety, and quality control of individual summer squashes, and the models developed with the MicroNIR-1700 instrument were those that provided more accuracy and precision, being the peduncle zone the part with higher nitrate content. CONCLUSIONS: It is in the peduncle zone, therefore, where measurements of this parameter must be carried out to decide on the destination of the harvested product. Summer squashes picked at the end of the harvest are those that must be used for baby-food production. © 2019 Society of Chemical Industry.


Assuntos
Cucurbita/crescimento & desenvolvimento , Frutas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Cucurbita/química , Cucurbita/metabolismo , Tomada de Decisões , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Nitratos/metabolismo , Controle de Qualidade , Estações do Ano , Verduras/química , Verduras/crescimento & desenvolvimento , Verduras/metabolismo
11.
Int J Mol Sci ; 20(13)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261811

RESUMO

: Sex expression is a complex process, and in-depth knowledge of its mechanism in pumpkin is important. In this study, young shoot apices at the one-true-leaf stage and 10-leaf stage in Cucurbita maxima trimonoecious line '2013-12' and subandroecious line '9-6' were collected as materials, and transcriptome sequencing was performed using an Illumina HiSeqTM 2000 System. 496 up-regulated genes and 375 down-regulated genes were identified between shoot apices containing mostly male flower buds and only female flower buds. Based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the differentially expressed genes were mainly enriched in the ethylene and auxin synthesis and signal transduction pathways. In addition, shoot apices at the 4-leaf stage were treated with the ethylene-releasing agent 2-chloroethylphosphonic acid (Ethrel), aminoethoxyvinyl glycine (AVG), AgNO3 and indoleacetic acid (IAA). The number of female flowers up to node 20 on the main stem of '2013-12' increased significantly after Ethrel and IAA treatment and decreased significantly after AVG and AgNO3 treatment. The female flowers in '9-6' showed slight changes after treatment with the exogenous chemicals. The expression of key genes in ethylene synthesis and signal transduction (CmaACS7, CmaACO1, CmaETR1 and CmaEIN3) was determined using quantitative RT-PCR, and the expression of these four genes was positively correlated with the number of female flowers in '2013-12'. The variations in gene expression, especially that of CmaACS7, after chemical treatment were small in '9-6'. From stage 1 (S1) to stage 7 (S7) of flower development, the expression of CmaACS7 in the stamen was much lower than that in the ovary, stigma and style. These transcriptome data and chemical treatment results indicated that IAA might affect pumpkin sex expression by inducing CmaACS7 expression and indirectly affecting ethylene production, and the ethylene synthesis and signal transduction pathways play crucial roles in pumpkin flower sex expression. A possible reason for the differences in sex expression between pumpkin lines '2013-12' and '9-6' was proposed based on the key gene expression. Overall, these transcriptome data and chemical treatment results suggest important roles for ethylene in pumpkin sex expression.


Assuntos
Cucurbita/genética , Etilenos/metabolismo , Flores/genética , Reguladores de Crescimento de Planta/metabolismo , Transcriptoma , Cucurbita/crescimento & desenvolvimento , Cucurbita/metabolismo , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Planta/genética
12.
J Exp Bot ; 70(20): 5879-5893, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31290978

RESUMO

Potassium (K+) is a critical determinant of salinity tolerance, and H2O2 has been recognized as an important signaling molecule that mediates many physiological responses. However, the details of how H2O2 signaling regulates K+ uptake in the root under salt stress remain elusive. In this study, salt-sensitive cucumber and salt-tolerant pumpkin which belong to the same family, Cucurbitaceae, were used to answer the above question. We show that higher salt tolerance in pumpkin was related to its superior ability for K+ uptake and higher H2O2 accumulation in the root apex. Transcriptome analysis showed that salinity induced 5816 (3005 up- and 2811 down-) and 4679 (3965 up- and 714 down-) differentially expressed genes (DEGs) in cucumber and pumpkin, respectively. DEGs encoding NADPH oxidase (respiratory burst oxidase homolog D; RBOHD), 14-3-3 protein (GRF12), plasma membrane H+-ATPase (AHA1), and potassium transporter (HAK5) showed higher expression in pumpkin than in cucumber under salinity stress. Treatment with the NADPH oxidase inhibitor diphenylene iodonium resulted in lower RBOHD, GRF12, AHA1, and HAK5 expression, reduced plasma membrane H+-ATPase activity, and lower K+ uptake, leading to a loss of the salinity tolerance trait in pumpkin. The opposite results were obtained when the plants were pre-treated with exogenous H2O2. Knocking out of RBOHD in pumpkin by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9] editing of coding sequences resulted in lower root apex H2O2 and K+ content and GRF12, AHA1, and HAK5 expression, ultimately resulting in a salt-sensitive phenotype. However, ectopic expression of pumpkin RBOHD in Arabidopsis led to the opposite effect. Taken together, this study shows that RBOHD-dependent H2O2 signaling in the root apex is important for pumpkin salt tolerance and suggests a novel mechanism that confers this trait, namely RBOHD-mediated transcriptional and post-translational activation of plasma membrane H+-ATPase operating upstream of HAK5 K+ uptake transporters.


Assuntos
Membrana Celular/metabolismo , Cucurbitaceae/metabolismo , Potássio/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Membrana Celular/efeitos dos fármacos , Cucurbita/efeitos dos fármacos , Cucurbita/metabolismo , Cucurbitaceae/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Tolerância ao Sal/fisiologia
13.
Sci Total Environ ; 686: 171-178, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31176816

RESUMO

Titanium dioxide nanoparticles (TiO2-NPs) are widely distributed in the environment. It has been demonstrated that TiO2-NPs could modify the environmental fate and bioavailability of organic pollutants, which affects ecological risks of TiO2-NPs and organic pollutants. In this study, the uptake, translocation and accumulation of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) in pumpkin plants was investigated in the presence of TiO2-NPs. We reported for the first time the negligible effects of TiO2-NPs at environmentally relevant concentrations (0.05-5 mg/L) on the uptake and accumulation of PFOA and PFOS in hydroponically grown pumpkin seedlings regardless of root, stem and leaf. This phenomenon was independent of the initial concentrations of PFOA/PFOS and TiO2-NPs in the exposure solution. Also, seedling mass and contents of chlorophyll and anthocyanin were not affected by the co-exposure. Adsorption tests demonstrated the negligible adsorption of PFOA/PFOS on TiO2-NPs in the exposure solution. Moreover, uptake of PFOA/PFOS was insensitive to aquaporin inhibitor AgNO3 but significantly inhibited by niflumic acid (anion channel blocker) and 2,4-dinitrophenol (metabolic inhibitor) whereas Ti concentration in root was not affected by niflumic acid and 2,4-dinitrophenol but significantly decreased by AgNO3, indicating that transport of PFOA/PFOS and TiO2-NPs were via different routes into the pumpkin seedling. It was proposed that different pathways by which TiO2-NPs and PFOA/PFOS transported into the pumpkin seedling and negligible adsorption of PFOA/PFOS on TiO2-NPs contributed to the negligible effects of TiO2-NPs on the uptake, translocation and accumulation of PFOA/PFOS in pumpkin seedlings. In total, this work would improve our understanding of the ecological risks of TiO2-NPs in the environment.


Assuntos
Ácidos Alcanossulfônicos/metabolismo , Caprilatos/metabolismo , Cucurbita/metabolismo , Fluorcarbonetos/metabolismo , Poluentes Químicos da Água/metabolismo , Hidroponia , Nanopartículas , Plântula , Titânio
14.
Environ Pollut ; 252(Pt A): 804-812, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31200206

RESUMO

6:2 fluorotelomer sulfonic acid (6:2 FTSA) is currently used as an alternative to perfluorooctanesulfonate (PFOS) and is widely detected in the environment. The uptake, translocation and biotransformation of 6:2 FTSA in pumpkin (Cucurbita maxima L.) were investigated by hydroponic exposure for the first time. The root concentration factor (RCF) of 6:2 FTSA was 2.6-24.2 times as high as those of perfluoroalkyl acids (PFAAs) of the same or much shorter carbon chain length, demonstrating much higher bioaccumulative ability of 6:2 FTSA in pumpkin roots. The translocation capability of 6:2 FTSA from root to shoot depended on its hydrophobicity. Six terminal perfluorocarboxylic acid (PFCA) metabolites, including perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), perfluoropentanoic acid (PFPeA), perfluorobutanoic acid (PFBA), perfluoropropionic acid (PFPrA) and trifluoroacetic acid (TFA) were found in pumpkin roots and shoots. PFHpA was the primary metabolite in roots, while PFBA was the major product in shoots. 1-aminobenzotriazole (ABT), a cytochromes P450 (CYPs) suicide inhibitor, could decrease the concentrations of PFCA products with dose-dependent relationships in pumpkin tissues, implying the role of CYP enzymes involved in plant biotransformation of 6:2 FTSA. This study indicated that the application of 6:2 FTSA can lead to the occurrence of PFCAs (C2-C7) in plants.


Assuntos
Alcanossulfonatos/análise , Biodegradação Ambiental , Cucurbita/metabolismo , Ácidos Sulfônicos/análise , Alcanossulfonatos/química , Ácidos Alcanossulfônicos , Transporte Biológico , Biotransformação , Caproatos/análise , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Fluorcarbonetos/análise , Ácidos Heptanoicos/análise , Interações Hidrofóbicas e Hidrofílicas , Hidroponia , Ácidos Pentanoicos/análise , Ácidos Sulfônicos/química , Triazóis/farmacologia , Ácido Trifluoracético/análise
15.
Plant Physiol ; 180(4): 1930-1946, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31213512

RESUMO

Floral nectar is a sugary solution produced by plants to entice pollinator visitation. A general mechanism for nectar secretion has been established from genetic studies in Arabidopsis (Arabidopsis thaliana); however, supporting metabolic and biochemical evidence for this model is scarce in other plant species. We used squash (Cucurbita pepo) to test whether the genetic model of nectar secretion in Arabidopsis is supported at the metabolic level in other species. As such, we analyzed the expression and activity of key enzymes involved in carbohydrate metabolism in squash nectaries throughout floral maturation and the associated starch and soluble sugars, as well as nectar volume and sugar under different growth conditions. Here we show that the steps that are important for nectar secretion in Arabidopsis, including nectary starch degradation, Suc synthesis, and Suc export, are supported by metabolic and biochemical data in C. pepo Additionally, our findings suggest that sugars imported from the phloem during nectar secretion, without prior storage as starch, are important for generating C. pepo nectar. Finally, we predict that trehalose and trehalose 6-P play important regulatory roles in nectary starch degradation and nectar secretion. These data improve our understanding of how nectar is produced in an agronomically relevant species with the potential for use as a model to help us gain insight into the biochemistry and metabolism of nectar secretion in flowering plants.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Cucurbita/metabolismo , Flores/metabolismo , Néctar de Plantas/metabolismo , Polinização/fisiologia , Transdução de Sinais/fisiologia
16.
Food Chem ; 294: 112-122, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126443

RESUMO

The feasibility of producing durum wheat pasta enriched with a lipophilic phytocomplex, extracted using supercritical carbon dioxide (SC-CO2), from ripe pumpkin, as free oil or as ready-to-mix oil/α-cyclodextrins (α-CDs) powder, was explored. Four types of pasta were prepared: (i) control spaghetti (S-CTRL); (ii) spaghetti supplemented with α-CDs (S-α-CD); (iii) spaghetti supplemented with pumpkin oil (S-Oil) and (iv) spaghetti supplemented with the pumpkin oil/α-CD powder (S-Oil/α-CD). The chemical, antioxidant, textural and sensory attributes of the different pasta were evaluated and compared. S-Oil and S-Oil/α-CD spaghetti were significantly enriched with phytosterols, squalene, carotenoids, tocochromanols and unsaturated fatty acids. Spaghetti containing α-CDs were slightly improved in terms of fiber content. Oil chlatration increased the stability of some bioactives during pasta production and ameliorated poor textural and sensory characteristics of the cooked spaghetti compared with S-Oil sample. S-Oil/α-CD spaghetti might be accepted by customers, if the potential health benefits were also explained.


Assuntos
Cromatografia com Fluido Supercrítico , Cucurbita/química , Óleos Voláteis/química , alfa-Ciclodextrinas/química , Dióxido de Carbono/química , Cromatografia Líquida de Alta Pressão , Culinária , Cucurbita/metabolismo , Fibras na Dieta/análise , Ácidos Graxos/análise , Farinha/análise , Cromatografia Gasosa-Espectrometria de Massas , Fenóis/análise , Espectrofotometria , Triticum/metabolismo
17.
Plant Sci ; 284: 99-107, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084885

RESUMO

Phloem-mobile mRNAs are assumed to contain sequence elements directing RNA to the phloem translocation pathway. One of such elements is represented by tRNA sequences embedded in untranslated regions of many mRNAs, including those proved to be mobile. Genomic RNAs of a number of plant viruses possess a 3'-terminal tRNA-like structures (TLSs) only distantly related to genuine tRNAs, but nevertheless aminoacylated and capable of interaction with some tRNA-binding proteins. Here, we elaborated an experimental system for analysis of RNA phloem transport based on an engineered RNA of Potato virus X capable of replication, but not encapsidation and movement in plants. The TLSs of Brome mosaic virus, Tobacco mosaic virus and Turnip yellow mosaic virus were demonstrated to enable the phloem transport of foreign RNA. A miRNA precursor, pre-miR390b, was also found to render RNA competent for the phloem transport. In line with this, sequences of miRNA precursors were identified in a Cucurbita maxima phloem transcriptome, supporting the hypothesis that, at least in some cases, miRNA phloem signaling can involve miRNA precursors. Collectively, the data presented here suggest that RNA molecules can be directed into the phloem translocation pathway by structured RNA elements such as those of viral TLSs and miRNA precursors.


Assuntos
MicroRNAs/metabolismo , Floema/metabolismo , RNA de Plantas/metabolismo , RNA de Transferência/metabolismo , Bromovirus/metabolismo , Cucurbita/metabolismo , Cucurbita/virologia , MicroRNAs/fisiologia , Floema/fisiologia , Potexvirus/metabolismo , RNA de Transferência/fisiologia , Vírus do Mosaico do Tabaco/metabolismo , Tymovirus/metabolismo
18.
J Photochem Photobiol B ; 195: 12-16, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31029913

RESUMO

The present work showed the green, eco-friendly synthesis of zinc oxide nanoparticles (ZnO NPs) using leaf extract of Cucurbita pepo. The prepared ZnO NPs were studied using different characterization techniques such as Fourier transform infrared (FTIR), X-ray diffraction (XRD), UV-Visible spectroscopy (UV-Vis) and Transmission electron microscopy (TEM). TEM images confirmed the formation of NPs with average size of 8 nm. XRD showed the crystalline nature of prepared ZnO NPs. This shows that the ZnO NPs induced cytotoxicity that affected the proliferation of MG63 osteoblast-like cells in a concentration dependent manner. Further, the ZnO NPs induced reduction in cell proliferation was confirmed by Fluorescein diacetate hydrolysis (FDA) staining. FDA staining results showed a reduction in fluorescence intensity with an increase in the concentration of ZnO NPs. The untreated control which was unaffected showed the highest fluorescence compared to ZnO NPs treated samples. A significantly diminished fluorescence was observed in samples incubated with 80 ppm ZnO NPs. In conclusion, these cell experimental results confirmed that the fabricated ZnO NPs are an important substitute for osteoporotic and bone tissue formation.


Assuntos
Cucurbita/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cucurbita/metabolismo , Química Verde , Humanos , Nanopartículas Metálicas/toxicidade , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Molecules ; 24(8)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991700

RESUMO

Food-waste is produced throughout all the food supply chain, with a large part already achieved at farm level. In fact, fruits and vegetables, which do not satisfy aesthetic demands, cannot be marketed, but their recovery could favour their valorisation for the obtainment of highly qualified goods. In this context, faulty zucchini fruits (cultivar 'Lungo Fiorentino'), intended for disposal, were rescued as effective, inexpensive and bio-sustainable source for cosmeceutical purposes. Zucchini fruits underwent extraction and fractionation to obtain ZLF-O and ZLF-A extracts, which were chemically characterized by UHPLC-HRMS. ZLF-A extract, rich in flavonols and flavones, scavenged massively DPPH• and ABTS•+, and was not cytotoxic at doses up to 200 µ g/mL. Thus, ZLF-A was incorporated into a base cream formula. Zucchini-based emulsion was deeply screened for its antiradical properties and cytotoxicity towards human keratinocytes and fibroblasts. ZLF-A-enriched cream, whose chemical stability was assessed over time and mimicking different storage conditions, was further tested on reconstructed epidermis disks (EpiskinTM). The recovery of valuable chemical substances from zucchini agro-food waste, complying with the principles of valorisation and sustainable development, can represent a new market force for local farmers. Data acquired were eager to convey a suitable reuse of nutraceuticals rich zucchini waste.


Assuntos
Cosmecêuticos/análise , Cucurbita/química , Frutas/química , Metaboloma , Cromatografia Líquida de Alta Pressão , Cosmecêuticos/química , Cucurbita/metabolismo , Frutas/metabolismo
20.
Food Chem ; 285: 186-193, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797334

RESUMO

In this study, the effect of the extraction method (mechanical pressing, MP and organic solvent, OS) and the specie (Cucurbita argyrosperma Huber, CA; and Cucurbita moschata Duchesne, CM) on the content of bioactive compounds and antioxidant activity of oil from pumpkin of Yucatan, Mexico was investigated. Between the two extraction methods, the oil extracted by MP obtained the highest values for total phenolic compounds (TPC), total carotenoids, squalene, quercetin, ß-carotene, fucosterol, stigmasterol and antioxidant activity (DPPH, ABTS and reducing power). Between the two species, the CM oil extracted with MP or OS exhibited the highest values for carotenoids, sterols and antioxidant activity (DPPH and ABTS). Thus, it can be concluded that the method and specie affect the composition of bioactive compounds and antioxidant activity of the pumpkin oil. This information is useful for the extraction of pumpkin oil with a higher content of compounds, of interest for the industry.


Assuntos
Antioxidantes/química , Cucurbita/química , Extração Líquido-Líquido/métodos , Óleos Vegetais/química , Pressão , Carotenoides/análise , Cromatografia Líquida de Alta Pressão , Cucurbita/metabolismo , México , Fenóis/análise , Fitosteróis/análise , Óleos Vegetais/isolamento & purificação , Análise de Componente Principal , Sementes/química , Sementes/metabolismo , Temperatura
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