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1.
Food Chem ; 307: 125521, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655264

RESUMO

The essential oils and antioxidant activity of four Thymus species were evaluated under five light spectra (namely, red, blue, red-blue, white, and greenhouse condition). The highest essential oil yield (4.17%) was observed under red light in T. migricus, while the lowest (1.05%) was observed in T. carmanicus under greenhouse conditions. Light quality also led to difference in essential oil constituents. The highest thymol (66%) was found in T. migricus exposed to blue light, while the least (1.69%) was observed in T. kotschyanus grown under red-blue light. The LED treatments did not induce any significant effect on carvacrol of Thymus species in comparison to the greenhouse condition. Finally, the analysis of variance indicates that the effect of light varied with the studied species. T. migricus performed the highest antioxidant capacity (IC50 = 176.8 µg/mL) under blue light. Overall, essential oil components as well as antioxidants showed significant responses to light emitting diodes wavelengths.


Assuntos
Antioxidantes/metabolismo , Luz , Timol/metabolismo , Thymus (Planta)/química , Análise de Variância , Antioxidantes/química , Cromatografia Gasosa , Análise por Conglomerados , Efeito Estufa , Óleos Voláteis/química , Análise de Componente Principal , Timol/química , Thymus (Planta)/crescimento & desenvolvimento , Thymus (Planta)/metabolismo
2.
Ecotoxicol Environ Saf ; 182: 109412, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31295658

RESUMO

Perennial plants and their associated microorganisms grow in the areas that may be contaminated with long-lived gamma-emitting radionuclides. This will induce gamma stress response in plants and their accompanying microorganisms. The present work investigated the growth and physiological responses of Epichloe endophyte infected tall fescue to gamma radiation, as well as whether the endophyte could persist and infect the host plant once exposed to gamma radiation. Seeds of Iranian native genotype of 75B+ of tall fescue were exposed to different doses, including 5.0, 10.0, 15.0, 20.0, 30.0 and 40.0 krad of gamma ray from a 60Co source. Irradiated and unirradiated seeds were sown in pots and grown under controlled conditions in the greenhouse. The growth and physiological parameters associated with plant tolerance to oxidative stress of host plants, as well as endophytic infection frequency (% of plants infected) and intensity (mean number of endophytic hyphae per the field of view), were examined in 3 months-old seedlings. The results indicated that all gamma radiation doses (except 5.0 kr) significantly reduced the height and survival percentage of the host plant. Days to the emergence of seedling increased gradually as gamma doses rose. A dose-rate dependent induction was seen for photosynthetic pigments and proline content. Malondialdehyde (MDA) content grew with elevation of irradiation doses. Depending on the dose and time, the activities of antioxidant enzymes in the host plant responded differently to gamma radiation. Gamma radiation altered the enzyme activities with sever decline in SOD and CAT activities. However, it had barely any effect on in APX and POD activities. The results also revealed that the persistence and intensity of endophyte were affected after gamma-ray irradiation. The initial percentage of tall fescue seeds infected with the endophyte was 91% in un-irradiated seeds. Presence of the viable endophyte started to decline significantly (23%) at 5.0 kr of gamma radiation. A dramatic reduction in the presence and intensity of endophyte occurred at 10.0 to 40.0 kr intensities. Gamma radiation × trait (GT)-biplot analysis indicated positive correlations between the endophyte symbiosis and antioxidant enzyme activities. Also, negative correlations were observed between the endophyte and MDA content in the host plant. Our results suggest that radiation stress (doses over 5.0 kr) caused reduction in the growth and antioxidant enzyme activities of the host plant that accompanied by a dramatic reduction in the persistence and intensity of endophyte fungi. Our findings have provided the basic information for future studies on the effect of gamma irradiation on the interaction between endophytic fungi and its host plant.


Assuntos
Endófitos/efeitos da radiação , Epichloe/efeitos da radiação , Festuca/efeitos da radiação , Raios gama , Relação Dose-Resposta à Radiação , Endófitos/crescimento & desenvolvimento , Epichloe/crescimento & desenvolvimento , Festuca/microbiologia , Festuca/fisiologia , Irã (Geográfico) , Doses de Radiação , Plântula/microbiologia , Plântula/fisiologia , Plântula/efeitos da radiação , Sementes/microbiologia , Sementes/fisiologia , Sementes/efeitos da radiação , Simbiose
3.
Plant Physiol Biochem ; 139: 548-557, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31029028

RESUMO

Stress priming (pre-exposure of plants to various types of moderate stresses) could affect plant responses to subsequent severe stresses. Drought stress is one of the major threats to plants which reduces the global agricultural productions. Here we demonstrated that light emitting diodes (LEDs)-driven tolerant to drought stress in lemon balm plantlets was highly correlated with priming with these lighting sources. Plantlets of the two genotypes of M. officinalis L. were first grown in 4 incubators with different LED lamps, including white LEDs (380-760 nm), blue LEDs (460 nm), red LEDs (650 nm) and red + blue LEDs (70%:30%), in a greenhouse for 4 weeks. The potted plants were then subjected to drought stress. Under drought stress, LED-primed plants maintained significantly higher fresh and dry weight, relative water content (RWC), concentration of soluble sugars, antioxidant activity and higher content of proline, H2O2, abscisic acid (ABA) and rosmarinic acid than non-primed plants. The results of Real-Time RT-PCR confirmed that LED pretreatment up-regulated the expression levels of respiratory burst oxidase homologues (RBOHs) or NADPH oxidase, 9-cis epoxy carotenoid dioxygenase (NCED), and rosmarinic acid synthase (RAS), while down-regulated that of ABA 8'-hydroxylase (ABA8Ox). These findings suggest, for the first time, that pre-treatment of plants with red + blue LEDs could improve their growth and quality under drought stress.


Assuntos
Secas , Iluminação , Melissa/fisiologia , Melissa/efeitos da radiação , Ácido Abscísico/metabolismo , Peróxido de Hidrogênio/metabolismo , Água/metabolismo
4.
Food Chem ; 289: 360-368, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955624

RESUMO

Ten sesame genotypes planted under two irrigation regimes of 60% and 90%, as the maximum allowable depletion (MAD), were used to investigate the effects of drought stress on certain quantitative and qualitative characters of sesame seeds with four contrasting coat colors. The polyphenolic components, sesamin, sesamolin, total flavonoid content (TFC), total phenolic content (TPC), radical scavenging activity (RSA), seed yield, and oil content of the seeds were also examined. Results revealed that drought decreased seed yield, oil content, sesamin, and quercetin but increased TFC, TPC, and RSA as well as most of polyphenolic components and sesamolin. The drought-tolerant genotypes including Markazi1 exhibited higher chlorogenic, ellagic, and p-coumaric acids as well as TFC, RSA, and rutin. While the dark-seeded sesame genotypes contained higher caffeic, ferulic, ellagic acids as well as TPC and RSA, the light-seeded ones were richer in sesamin and sesamolin as well as p-coumaric and gallic acids. The findings of the study provided basic information on the changes in some seed secondary metabolites when sesame was subjected to drought stress. The results also confirmed not only the presence of considerable amounts of antioxidants in sesame seeds but also differences in secondary metabolite levels among the sesame seeds with different seed coat colors.


Assuntos
Dioxóis/análise , Lignanas/análise , Pigmentos Biológicos/análise , Polifenóis/análise , Sementes/química , Antioxidantes/análise , Secas , Flavonoides/análise , Depuradores de Radicais Livres/análise , Genótipo , Fenóis/farmacologia , Sementes/efeitos dos fármacos , Sesamum/química , Sesamum/genética
5.
Int J Phytoremediation ; 20(10): 995-1006, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30095312

RESUMO

Distichlis spicata and Suaeda aegyptiaca are two potential halophytic plant species for bioremediation of salt degraded soils, and development of saline agriculture. The physiological responses of the species to different levels of salinity (EC 0, 12, 24, 36, and 48 dS/m) in a controlled environment experiment were studied. Both species showed a high level of tolerance to elevated concentrations of salt in the irrigation water. The shoot fresh and dry weights in S. aegyptiaca increased till 36 dS/m and were sustained under 48 dS/m while in D. spicata, both parameters decreased as salinity increased. Glycine betaine accumulation did not change in D. spicata with increasing salinity, whereas proline content revealed a marked increase of 7.13 fold in 48 dS/m salinity compared to the control, which showed its critical osmoprotection role in the plant. In S. aegyptiaca, both osmolytes content significantly increased at high salinity levels (36 and 48 dS/m) up to 3.22 and 2.0 folds, respectively. Overall, S. aegyptiaca had a better potential of Na+ phytoremediation, and tolerated higher salinity compared to D. spicata. In contrast, the vigorous root and rhizome growth in D. spicata made it a proper solution for protecting the soils against further erosion under saline conditions.


Assuntos
Chenopodiaceae , Plantas Tolerantes a Sal , Biodegradação Ambiental , Salinidade , Solo , Água
6.
Chem Biodivers ; 15(6): e1700565, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29687655

RESUMO

Essential oil (EO) composition, phenolic content, and antioxidant activity were investigated in 17 P. abrotanoides populations collected from different geographical regions in Iran. The highest (3.61%) and lowest (1.25%) essential oil yields were measured in populations from Semnan Province (PSESM2 ) and PISKS from Isfahan Province, respectively. GC/MS analysis identified camphor (4.05 - 35.94%), 1,8-cineole (7.15 - 24.34%), borneol (0 - 21.75%), and α-pinene (2.05 - 10.33%) as the main constituents of Perovskia essential oil. Cluster analysis classified the studied populations into four different groups: (I) high camphene, (II) high camphor/1,8-cineole, (III) high borneol/δ-3-carene, and (IV) high α-cadinol/trans-caryophyllene. The highest flavonoid and phenolic contents were detected in PISAK from Isfahan Province (4.09 ± 0.05 mgQE/gDW, 58.51 ± 1.63 mgGAE/gDW) and PKRGS from Khorasan Province (3.80 ± 0.002 mgQE/gDW, 66.86 ± 0.002 mgGAE/gDW). DPPH and reducing power activity model systems identified PMASA and PKRKL as the populations with the highest antioxidant activity. Finally, the data obtained represented valuable information for introducing elite populations with EO components favorable to pharmaceutical and industrial applications.


Assuntos
Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Lamiaceae/química , Óleos Voláteis/farmacologia , Picratos/antagonistas & inibidores , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/metabolismo , Análise por Conglomerados , Irã (Geográfico) , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Picratos/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-29505940

RESUMO

Two novel tetra-coordinated Cobalt(II) and Zinc (II) chelate series with the general formula of [Co (L)·2H2O] (1) and [Zn (L)] (2) [L=N-2-hydroxyacetophenon-N'-2-hydroxynaphthaldehyde-1,2 phenylenediimine)] with biologically active Schiff base ligands were synthesized and recognized by elemental analysis and multi-nuclear spectroscopy (IR and 1H and 13C NMR); then, their biological activities including DNA and protein interactions were studied. The interaction of the synthesized compounds with bovine serum albumin (BSA) was investigated via fluorescence spectroscopy, showing the affinity of the complexes for these proteins with relatively high binding constant values and the changed secondary BSA structure in the presence of the complexes. The interaction of these compounds with CT-DNA was considered by UV-Vis technique, emission titration, viscosity measurements, helix melting methods, and circular dichroism (CD) spectroscopy, confirming that the complexes were bound to CT-DNA by the intercalation binding mode. Furthermore, the complexes had the capability to displace the DNA-bound MB, as shown by the competitive studies of these complexes with methylene blue (MB), thereby suggesting the intercalation mode for the competition. Finally, the theoretical studies carried out by the docking method were performed to calculate the binding constants and recognize the binding site of the BSA and DNA by the complexes. In addition, in vitro and in silico studies showed that the compounds were degradable by bacterial and fungal biodegradation activities.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Bases de Schiff/química , Soroalbumina Bovina/química , Compostos de Zinco/química , Sítios de Ligação , Dicroísmo Circular , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , DNA/química , DNA/metabolismo , Espectroscopia de Ressonância Magnética , Azul de Metileno/química , Simulação de Acoplamento Molecular , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Compostos de Zinco/síntese química
8.
Chem Biodivers ; 15(6): e1700562, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29575789

RESUMO

Total flavonoid content (TFC) and cyanidin-3-glucoside (Cyd-3-glu) of seed and seed coat extract of 16 genotypes from five species of Carthamus were studied, and their major polyphenolic compounds and antioxidant activity of the seed coat extracts were determined using HPLC analysis and DPPH assay, respectively. Additionally, fatty acids composition of the seed oil was analyzed by GC. In general, TFC and Cyd-3-glu content of seed coat extracts were higher than those of seed extracts. A novel breeding line with black seed coat (named A82) depicted lower TFC (3.79 mg QUE/g DW) but higher Cyd-3-glu (24.64 mg/g DW) compared to the white and other seed-pigmented genotypes. DPPH radical scavenging activity showed a strong association with Cyd-3-glu content (r = 0.84), but no correlation with TFC (r = -0.32). HPLC analysis of seed coat extracts revealed that four compounds were dominant constituents including rutin (7.23 - 117.95 mg/100 g DW), apigenin (4.37 - 64.88 mg/100 g DW), quercetin (3.09 - 14.10 mg/100 g DW), and ferulic acid (4.49 - 30.41 mg/100 g DW). Interestingly, the genotype A82 with an appropriate polyunsaturated/saturated fatty acids index (5.46%) and a moderate linoleic fatty acid content (64.70%) had higher nutritional and pharmaceutical value than all the other genotypes.


Assuntos
Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Carthamus/química , Ácidos Graxos/farmacologia , Picratos/antagonistas & inibidores , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Sementes/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/metabolismo , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Picratos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Polifenóis/química , Polifenóis/isolamento & purificação , Especificidade da Espécie
9.
J Biomol Struct Dyn ; 36(2): 532-549, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28271957

RESUMO

[C20H17N3O2] and cobalt (II) complex [Co(L2)(MeOH)2].ClO4, (L2 = 4-((E)-1-((2-(((E)-pyridin-2-ylmethylene) amino) phenyl) imino) ethyl) benzene-1, 3-diol) novel Schiff base has been synthesiszed and chracterized by Fourier transform infrared, UV-vis, 1H-NMR spectroscopy, and elemental analysis techniques. The interaction of Co(II) complex with DNA and BSA was investigated by electronic absorption spectroscopy, fluorescence spectroscopy, circular dichroism, and thermal denaturation studies. Our experiments indicate that this complex could strongly bind to CT-DNA via minor groove mechanism. In addition, fluorescence spectrometry of BSA with the complex showed that the fluorescence quenching mechanism of BSA was of static type. The complex exhibited significant in vitro cytotoxicity against three human cancer cell lines (JURKAT, SKOV3, and U87). The molecular docking experiment effectively proved the binding of complex to DNA and BSA. Finally, antibacterial assay over gram-positive and gram-negative pathogenic bacterial strains was studied.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Neoplasias/tratamento farmacológico , Bases de Schiff/química , Antibacterianos/química , Antibacterianos/farmacologia , Dicroísmo Circular , Cobalto/farmacologia , Complexos de Coordenação/farmacologia , Cobre/química , Cristalografia por Raios X , Humanos , Células Jurkat , Ligantes , Simulação de Acoplamento Molecular , Soroalbumina Bovina/química , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 180: 144-153, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28284160

RESUMO

In this investigation, the structure of bidentate N,N-Schiff base ligand of vanillin, (E)-4-(((2-amino-5-nitrophenyl)imino)methyl)-2-methoxyphenol (HL) was determined by single crystal X-ray diffraction. The interaction of new [CuL2], [NiL2] and [VOL2] complexes with DNA and BSA was explored through UV-Vis and fluorescence spectroscopy. The electronic spectra changes displayed an isosbestic point for the complexes upon titration with DNA. The Kb values for the complexes [CuL2], [NiL2] and [VOL2] were 2.4×105, 1.9×105 and 4.2×104, respectively. [CuL2] complex was bound more toughly than [NiL2] and [VOL2] complexes. These complexes had a significant interaction with Bovine Serum Albumin (BSA) and the results demonstrated that the quenching mechanism was a static procedure. Also, the complexes interacted with BSA by more than one binding site (n>1). Finally, the theoretical studies were performed using the docking method to calculate the binding constants and recognize the binding site of the DNA and BSA with the complexes. The ligand and complexes including Ni2+, Cu2+ and VO2+ ions were colonized by fungal growth.


Assuntos
Benzaldeídos , DNA , Metais Pesados , Bases de Schiff , Soroalbumina Bovina , Animais , Benzaldeídos/química , Benzaldeídos/metabolismo , Bovinos , DNA/química , DNA/metabolismo , Metais Pesados/química , Metais Pesados/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica , Bases de Schiff/química , Bases de Schiff/metabolismo , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência
11.
Braz. arch. biol. technol ; 60: e17160564, 2017. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-951443

RESUMO

ABSTRACT Safflower (Carthamus tinctorius L.) is an annual herbaceous plant, cultivated mainly for the seed which is used for edible oil extraction and bird feeding. This study was designed to evaluate the safety of a new pigmented variety of safflower (A82) seeds. The results showed that oral administration of A82 seeds significantly increased the body weight of male rats in a dose-dependent manner (p<0.05). Biochemical tests showed that A82 seeds significantly increased the serum levels of AST (Aspartate aminotransferase) (p<0.05), slightly reduced the serum levels of ALT (Alanine aminotransferase) and significantly reduced ALP (p<0.05) levels in a dose dependent manner. BUN (Blood Urea Nitrogen) and Cr (Creatinine) were not significantly changed in A82 seed treated groups. Also, testosterone levels were not significantly changed by administration of different doses of A82. However, Johnson scoring showed slightly decrease in experimental groups. No organ weight or histological changes were observed in liver, kidney, spleen, heart and brain of A82 seed treated animals. These results indicate that A82 seeds have not any toxic effects in Wistar rats. Future studies are required to clarify the exact mechanism by which A82 seeds alter AST levels and body weight in rat.

12.
Mycorrhiza ; 26(1): 67-76, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26041568

RESUMO

Mycorrhizal fungi are key microorganisms for enhancing phytoremediation of soils contaminated with heavy metals. In this study, the effects of the arbuscular mycorrhizal fungus (AMF) Funneliformis mosseae (=Glomus mosseae) on physiological and molecular mechanisms involved in the nickel (Ni) tolerance of tall fescue (Festuca arundinacea = Schedonorus arundinaceus) were investigated. Nickel addition had a pronounced negative effect on tall fescue growth and photosynthetic pigment contents, as well as on AMF colonization. Phosphorus content increased markedly in mycorrhizal plants (M) compared to non-inoculated (NM) ones. However, no significant difference was observed in root carbohydrate content between AMF-inoculated and non-inoculated plants. For both M and NM plants, Ni concentrations in shoots and roots increased according to the addition of the metal into soil, but inoculation with F. mosseae led to significantly lower Ni translocation from roots to the aboveground parts compared to non-inoculated plants. ABC transporter and metallothionein transcripts accumulated to considerably higher levels in tall fescue plants colonized by F. mosseae than in the corresponding non-mycorrhizal plants. These results highlight the importance of mycorrhizal colonization in alleviating Ni-induced stress by reducing Ni transport from roots to shoots of tall fescue plants.


Assuntos
Transportadores de Cassetes de Ligação de ATP/biossíntese , Festuca/microbiologia , Metalotioneína/biossíntese , Micorrizas/metabolismo , Níquel/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Metabolismo dos Carboidratos , Carotenoides/metabolismo , Clorofila/metabolismo , Festuca/crescimento & desenvolvimento , Festuca/metabolismo , Glomeromycota/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Minerais/metabolismo , Micorrizas/genética , Micorrizas/fisiologia , Níquel/química , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Solo/química , Poluentes do Solo/metabolismo , Estresse Fisiológico
13.
Ecotoxicol Environ Saf ; 120: 13-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26024809

RESUMO

Epichloe endophytes are symbiotic fungi which unlike mycorrhiza grow within aerial parts of host plants. The fungi may increase host tolerance to both biotic and abiotic stresses. In this study, the effect of endophyte infection on growth and tolerance, carbohydrate contents and ABC (ABC transporter) and MET (metallothionein) expression in the leaves of tall fescue (Festuca arundinacea) plants cultivated in Ni polluted soil were evaluated. The endophyte infected (E+) and non-infected (E-) fescue plants were cultivated in soil under different Ni concentrations (30, 90 and 180mgkg(-1)). Growth parameters including root, shoot, total biomass, tiller number and total chlorophyll content of plants and H2O2 content of shoots were measured at the end of experiment. Ni translocation to the shoots, carbohydrate contents in roots and expression of ABC and MET of the leaves were also measured after 10 weeks of growth. Results demonstrated the beneficial effect of endophyte association on growth and Ni tolerance of tall fescue under Ni stress through an avoidance mechanism (reduction of Ni accumulation and translocation to the shoots). Endophyte infected plants showed less ABC and MET expression compared to the endophyte free plants. In endophyte free plants, H2O2 production had a significant positive correlation with genes expression, indicating that an increase in H2O2 might be involved in the up-regulation of ABC and MET under Ni stress.


Assuntos
Endófitos/patogenicidade , Epichloe/patogenicidade , Festuca/metabolismo , Metalotioneína/metabolismo , Micoses/fisiopatologia , Níquel/toxicidade , Poluentes do Solo/toxicidade , Transportadores de Cassetes de Ligação de ATP/genética , Biomassa , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Regulação para Cima
14.
Int J Phytoremediation ; 17(1-6): 456-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25495936

RESUMO

The effect of Neotyphodium endophytes on growth parameters and zinc (Zn) tolerance and uptake was studied in two grass species of Festuca arundinacea and Lolium perenne. Plants were grown under different Zn concentrations (control, 200, 400, 800, and 1800 mg kg(-1)) in potted soil for 5 months. The results showed that the number of plant tillers was 85 and 51% greater in endophyte infected Festuca (FaEI) and Lolium (LpEI), respectively, compared to their endophyte free (EF) plants. Roots and shoots dry weights in infected Festuca were 87 and 9% greater than non-infected counterparts but in opposite, EF Lolium had 47 and 8% greater root and shoot dry weights than LpEI. Endophyte infected Festuca and Lolium improved chlorophyll fluorescence as Fv/Fm at high concentrations of Zn, showing their better chlorophyll functions and significant reduction of Zn stress in endophyte infected plants. Shoots of endophyte infectedFestuca had 82% greater concentration of Zn than EF Festuca when grown in soil containing 1800 mg kg(-1) Zn. Festuca and Lolium may tolerate high Zn concentration in soil without reduction in shoot and root growth. Endophyte infection in Festuca may help the grass accumulate and transport more Zn in aboveground parts under Zn-stress, thereby aiding phytoremediation of contaminated soils.


Assuntos
Recuperação e Remediação Ambiental/métodos , Festuca/metabolismo , Festuca/microbiologia , Lolium/metabolismo , Lolium/microbiologia , Neotyphodium/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Zinco/metabolismo , Biodegradação Ambiental , Endófitos/crescimento & desenvolvimento , Endófitos/metabolismo , Recuperação e Remediação Ambiental/instrumentação , Festuca/química , Lolium/química , Neotyphodium/metabolismo , Poluentes do Solo/análise , Zinco/análise
15.
Philos Trans R Soc Lond B Biol Sci ; 369(1640): 20130243, 2014 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-24591723

RESUMO

Providing an adequate quantity and quality of food for the escalating human population under changing climatic conditions is currently a great challenge. In outdoor cultures, sunlight provides energy (through photosynthesis) for photosynthetic organisms. They also use light quality to sense and respond to their environment. To increase the production capacity, controlled growing systems using artificial lighting have been taken into consideration. Recent development of light-emitting diode (LED) technologies presents an enormous potential for improving plant growth and making systems more sustainable. This review uses selected examples to show how LED can mimic natural light to ensure the growth and development of photosynthetic organisms, and how changes in intensity and wavelength can manipulate the plant metabolism with the aim to produce functionalized foods.


Assuntos
Agricultura/métodos , Metabolismo Energético/fisiologia , Luz , Iluminação/instrumentação , Fotossíntese/fisiologia , Desenvolvimento Vegetal/efeitos da radiação , Metabolismo Energético/efeitos da radiação , Modelos Biológicos , Fotossíntese/efeitos da radiação
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 183-90, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24667423

RESUMO

Zinc (II) complexes with non-steroidal anti-inflammatory drugs (NSAIDs) naproxen (nap) and ibuprofen (ibu) were synthesized in the presence of nitrogen donor ligands (thiocyanate or azide). The complexes were characterized by elemental analysis, FT-IR, (1)H NMR and UV-Vis spectroscopes. The binding modes of the ligands in complexes were established by means of molecular modeling of the complexes, and calculation of their IR, NMR and absorption spectra at DFT (TDDFT)/B3LYP level were studied. The experimental and calculated data verified monodentate binding through the carboxylic oxygen atoms of anti-inflammatory drugs in the zinc complexes. The calculated (1)H, FT-IR and UV-Vis data are in better agreement with the experimental results, and confirm the predicted tetrahedral structures for the Zn (II) complexes. In addition to DFT calculations of complexes, natural bond orbital (NBO) was performed at B3LYP/6-31+G(d,p) level of theory. Biological studies showed the antibacterial activity of zinc complexes against Gram-positive and Gram-negative bacterial strains.


Assuntos
Antibacterianos , Anti-Inflamatórios não Esteroides/química , Azidas/química , Escherichia coli/crescimento & desenvolvimento , Ibuprofeno/química , Naproxeno/química , Staphylococcus aureus/crescimento & desenvolvimento , Tiocianatos/química , Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia
17.
Mycologia ; 104(6): 1281-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675051

RESUMO

Host specificity of Neotyphodium species symbiotic with three grass species, Festuca arundinacea, Festuca pratensis and Lolium perenne, was studied based on comparisons of amplified fragment length polymorphisms (AFLP) between hosts and their corresponding endophytes. Endophytic fungi were isolated from 24 accessions of host plants. Neotyphodium identity was determined based on morphological characteristics observed in cultures and polymerase chain reaction analysis using specific primers. The results of AFLP data analysis revealed high genetic variation in plant and fungal endophyte species. Plant AFLP genotypes from different species clustered in three distinctive groups, congruent with species. A cluster analysis of AFLP data grouped endophytic isolates according to their host species and secondarily according to their host geographic distribution. The result of the AMOVA on AFLP data accounted for a large and significant proportion of genetic variation due to differences among plant and endophyte species. Phylogenetic groups of isolates corresponded to their respective host genotypes based on maximum parsimony phylograms. Comparisons of the two phylograms illustrated a significant congruence between nodes and branches of host and endophyte clades. These results strongly suggest host specificity of Neotyphodium fungal endophytes with their geographically distant host grasses within each species.


Assuntos
Festuca/microbiologia , Variação Genética , Especificidade de Hospedeiro , Lolium/microbiologia , Neotyphodium/isolamento & purificação , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Análise por Conglomerados , Primers do DNA , DNA Fúngico/genética , DNA de Plantas/genética , Endófitos , Genótipo , Neotyphodium/citologia , Neotyphodium/genética , Filogenia , Esporos Fúngicos/citologia , Esporos Fúngicos/genética , Esporos Fúngicos/isolamento & purificação , Simbiose
18.
Amino Acids ; 42(5): 1997-2007, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21607747

RESUMO

N,N'-Bis[2-(methyl-3-(4-hydroxyphenyl)propanoate)]isophthaldiamide (5), a novel diol monomer containing chiral group, was prepared by the reaction of S-tyrosine methyl ester (3) with isophthaloyl dichloride (4a). A new family of optically active and potentially biodegradable poly(ester-amide)s (PEAs) based on tyrosine amino acid were prepared by the polycondensation reaction of diol monomer 5 with several aromatic diacid chlorides. The resulting new polymers were obtained in good yields with inherent viscosities ranging between 0.25 and 0.42 dL/g and are soluble in polar aprotic solvents. They showed good thermal stability and high optical purity. The synthetic compounds were characterized and studied by FT-IR, 1H-NMR, specific rotation, elemental and thermogravimetric analysis (TGA) techniques and typical ones by 13C-NMR, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM) analysis. Soil burial test of the diphenolic monomer 5, and obtained PEA6a, and soil enzymatic assay showed that the synthesized diol and its polymer are biologically active and probably biodegradable in soil environment.


Assuntos
Nylons/síntese química , Poliésteres/síntese química , Polímeros/química , Polímeros/síntese química , Tirosina/química , Biodegradação Ambiental , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nylons/química , Ácidos Ftálicos/síntese química , Ácidos Ftálicos/química , Poliésteres/química , Solo/química , Solubilidade , Tirosina/análogos & derivados , Tirosina/síntese química , Viscosidade
19.
Amino Acids ; 41(5): 1215-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21069397

RESUMO

The present demand for a drastic reduction in environmental pollution is extended to qualitative change in the approach to development of biodegradable polymers. The aim of this article is to focus on the synthesis of biodegradable optically active poly(ester-imide)s (PEI)s, which compose of different amino acids in the main chain as well as in the side chain. These polymers were synthesized by polycondensation of diacid monomers such as 5-(2-phthalimidyl-3-methyl butanoylamino) isophthalic acid (1), 5-(4-methyl-2-phthalimidyl pentanoylamino)isophthalic acid (2) with N,N'-(pyromellitoyl)-bis-L: -tyrosine dimethyl ester (3) as a phenolic diol. The direct polycondensation reaction was carried out in a system of tosyl chloride, pyridine and N,N-dimethylformamide as a condensing agent under conventional heating conditions. The optically active PEIs were obtained in good yield and moderate inherent viscosity. The synthesized polymers were characterized by means of FT-IR, (1)H-NMR, elemental and thermo gravimetric analysis techniques. In addition, in vitro toxicity and soil burial test were employed for assessing the sensitivity of these compounds to microbial degradation. To this purpose, biodegradability behavior of the monomers and polymers were investigated in culture media and soil condition. The results of this study revealed that synthesized monomers and their derived polymers are biologically active and probably microbiologically biodegradable.


Assuntos
Bactérias/metabolismo , Fungos/metabolismo , Polímeros/síntese química , Polímeros/metabolismo , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Ésteres/química , Ésteres/metabolismo , Fungos/crescimento & desenvolvimento , Imidas/química , Imidas/metabolismo , Cinética , Leucina/química , Leucina/metabolismo , Estrutura Molecular , Polímeros/química , Tirosina/química , Tirosina/metabolismo , Valina/química , Valina/metabolismo
20.
Amino Acids ; 40(2): 611-21, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20632046

RESUMO

In this investigation N,N'-(pyromellitoyl)-bis-L-tyrosine dimethyl ester (7) as a chiral bioactive diphenolic monomer was prepared in three steps. The aim of this work was to obtain novel optically and biologically active pseudo-poly(amino acid)s (PAA)s that are more soluble in common organic solvents while maintaining their high thermal stability. Thus, several new, highly soluble, thermally stable, optically active and biodegradable PAAs containing different amino acid moieties in the main chain were prepared with moderate molecular weights via direct polycondensation using tosyl chloride, pyridine and N,N'-dimethylformamide as a condensing agent. The resulting novel polymers were characterized with FT-IR, (1)H-NMR, elemental and thermogravimetric analysis techniques. In addition, in vitro toxicity and biodegradability behavior of the diphenolic monomer 7, different synthetic diacids (3a-3e) and obtained PAAs, which were investigated in culture media, showed that the synthesized compounds and polymers derived from them are biologically active and biodegradable under a natural environment.


Assuntos
Anti-Infecciosos/síntese química , Tirosina/análogos & derivados , Tirosina/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Estrutura Molecular , Polímeros/síntese química , Polímeros/química , Polímeros/farmacologia , Solubilidade , Tirosina/química , Tirosina/farmacologia
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