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1.
Nutrition ; 123: 112426, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38581846

RESUMO

OBJECTIVE: Studies that have investigated the effect of nutritional counseling during the prenatal period on the follow-up outcomes of children at 6 mo have produced inconclusive results. The present study aimed to investigate the effect of nutritional counseling, based on the NOVA food classification, encouraging the consumption of fresh and minimally processed foods, with overweight adult pregnant women on infant growth at 6 mo of age. METHODS: A randomized controlled trial with 195 pairs of pregnant overweight women and their infants at 6 mo of age was conducted in a Brazilian municipality. The pregnant women were allocated to the control group (CG) or intervention group (IG) at the beginning of the pregnancy. The IG received three sessions of nutrition counseling throughout the pregnancy. Linear regression models were used to investigate the effect of the nutritional counseling on infant growth. RESULTS: One hundred ninety-five mother-infant pairs with complete data were included (96 CG, and 99 IG). The mean ± SD infant weight (g) at 6 mo was 7856.1 ± 1.1, and length (cm) was 67.0 ± 2.9. There were no differences in maternal and newborn characteristics between the groups. In the linear regression models, the counseling had no effect on anthropometric parameters of the infants at 6 mo of age: weight-for-length Z-score (ß 0.089 [95% CI -0.250; 0.427], P = 0.61); length-for-age Z-score (ß 0.032 [95% CI -0.299; 0.363], P = 0.85); weight-for-age Z-score (ß 0.070 [95% CI -0.260; 0.400], P = 0.68); BMI-age Z-score (ß 0.072 [95% CI -0.270; 0.414], P = 0.68). CONCLUSIONS: There was no effect on infant growth at 6 mo of age after the nutritional counseling during pregnancy. Future studies are needed to confirm this hypothesis.


Assuntos
Desenvolvimento Infantil , Aconselhamento , Sobrepeso , Humanos , Feminino , Gravidez , Lactente , Aconselhamento/métodos , Sobrepeso/terapia , Adulto , Brasil , Cuidado Pré-Natal/métodos , Complicações na Gravidez , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Modelos Lineares
2.
An Acad Bras Cienc ; 95(1): e20201480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132745

RESUMO

Banana preserve is produced by mixing the puree of the fruit with sucrose and organic acids. However, concerns about body esthetics or health reasons have encouraged the search for low-calorie products. Therefore, the objective of this study was to evaluate the effect of calcium chloride (CaCl2), carrageenan gum, and low methoxyl pectin (LM-pectin) on the physicochemical and sensory characteristics of sugar-free banana preserves. By using a central composite rotational design (CCRD) of 2³ + 6 axial points + 4 central points, we obtained 18 formulations that were further tested. Lower CaCl2 concentrations (0.54% to 0.61%) resulted in preserves with lower pH and more vivid color. The increased concentration of LM-pectin (1.40% to 1.64%) resulted in formulations with a yellowish-red hue and with lower moisture, thus, reducing the flavor and purchase intention of the product. Higher concentrations of carrageenan gum (1.04% to 1.15%) decreased the perception of banana preserve aroma. Therefore, concentrations of CaCl2 ranging from 0.54% to 0.61%, carrageenan gum ranging from 0.74% to 0.89% and LM-pectin ranging from 1.40% to 1.64% resulted in sugar-free banana preserves with ideal sweetness and consistency and were, therefore, more acceptable.


Assuntos
Musa , Cloreto de Cálcio , Carragenina , Pectinas/farmacologia , Frutas
3.
Pest Manag Sci ; 74(6): 1449-1456, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29250895

RESUMO

BACKGROUND: Chitinases (EC 3.2.1.14) are enzymes involved in the breaking of the ß-1,4-glycosidic linkages of chitin. In insects, chitin is present mainly in the cuticle and in peritrophic membranes and peritrophic gel. Enzymes with the potential to damage peritrophic membranes and gel, such as chitinase, have been associated with plant defense systems. Identification and characterization of seed coat chitinase as a plant defense molecule may indicate a more effective target for manipulation strategies, which may lead to the prevention of consumption of embryonic tissues by larvae and consequently minimization of seed damage. RESULTS: We studied the efficiency of soybean seed coat chitinase as a defense molecule against the insect Callosobruchus maculatus. The seed coat chitinase was isolated and identified by mass spectrometry, immunoreacted with an anti-chitinase antibody and shown to have activity against chitin azure and 4-methylumbelliferyl ß-D-N,N',N''-triacetylchitotrioside. A chitinase fraction incorporated in artificial cotyledons at 0.1% reduced larval survival by approximately 77%, and at 0.5%, the reduction in larval mass was 60%. Fluorescein isothiocyanate (FITC)-labeled chitinase was detected in the guts and feces of larvae. At 25% in thick artificial seed coats, chitinase showed a high toxicity to larvae, with mortality of 90% and a reduction of larval mass of 87%. CONCLUSION: Seed coat chitinase is an important seed defense molecule not only in the cotyledons but also in seed coats, acting as part of the array of defense mechanisms against Callosobruchus maculatus. © 2017 Society of Chemical Industry.


Assuntos
Quitinases/farmacologia , Besouros/efeitos dos fármacos , Glycine max/química , Herbivoria/efeitos dos fármacos , Inseticidas/farmacologia , Proteínas de Plantas/farmacologia , Sementes/química , Animais , Besouros/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento
4.
BMC Biochem ; 15: 7, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24690228

RESUMO

BACKGROUND: Defensins are basic, cysteine-rich antimicrobial peptides that are important components of plant defense against pathogens. Previously, we isolated a defensin, PvD1, from Phaseolus vulgaris L. (common bean) seeds. RESULTS: The aim of this study was to overexpress PvD1 in a prokaryotic system, verify the biologic function of recombinant PvD1 (PvD1r) by comparing the antimicrobial activity of PvD1r to that of the natural defensin, PvD1, and use a mutant Candida albicans strain that lacks the gene for sphingolipid biosynthesis to unravel the target site of the PvD1r in C. albicans cells. The cDNA encoding PvD1, which was previously obtained, was cloned into the pET-32 EK/LIC vector, and the resulting construct was used to transform bacterial cells (Rosetta Gami 2 (DE3) pLysS) leading to recombinant protein expression. After expression had been induced, PvD1r was purified, cleaved with enterokinase and repurified by chromatographic steps. N-terminal amino acid sequencing showed that the overall process of the recombinant production of PvD1r, including cleavage with the enterokinase, was successful. Additionally, modeling revealed that PvD1r had a structure that was similar to the defensin isolated from plants. Purified PvD1 and PvD1r possessed inhibitory activity against the growth of the wild-type pathogenic yeast strain C. albicans. Both defensins, however, did not present inhibitory activity against the mutant strain of C. albicans. Antifungal assays with the wild-type C. albicans strains showed morphological changes upon observation by light microscopy following growth assays. PvD1r was coupled to FITC, and the subsequent treatment of wild type C. albicans with DAPI revealed that the labeled peptide was intracellularly localized. In the mutant strain, no intracellular labeling was detected. CONCLUSION: Our results indicate that PvD1r retains full biological activity after recombinant production, enterokinase cleavage and purification. Additionally, our results from the antimicrobial assay, the microscopic analysis and the PvD1r-FITC labeling assays corroborate each other and lead us to suggest that the target of PvD1 in C. albicans cells is the sphingolipid glucosylceramide.


Assuntos
Antifúngicos/metabolismo , Defensinas/metabolismo , Phaseolus/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Sequência de Bases , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Clonagem Molecular , Defensinas/química , Defensinas/genética , Expressão Gênica , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Sementes/metabolismo
5.
Biopolymers ; 100(2): 132-40, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23616096

RESUMO

Recent results from our laboratory have previously shown the purification of a small serine proteinase inhibitor (PI), named CaTI1, from Capsicum annuum seeds. This work demonstrated the characterization of CaTI now named CaTI1, and the identification of two other small serine PIs, named CaTI2 and CaTI3, also present in these seeds. CaTI1 presented molecular mass of 6 kDa and pI value of ∼9.0. CaTI1 inhibited both trypsin and chymotrypsin with inhibition constants (Ki and Ki') of 14 and 2.8 nM for trypsin and 4.3 and 0.58 nM for chymotrypsin, respectively. Circular dichroism analysis suggested the predominance of both disordered and ß-strands regions in the secondary structure. CaTI1 presented striking physico-chemical stability. In an attempt to get the entire sequence of CaTI1 we found another PI called CaTI2. The discussion of this finding is in the main text. A degenerate primer was designed based on the sequence of trypsin inhibitor CaTI1 in an attempt to achieve the cloning of this PI. Surprisingly, the alignment of the predicted peptide derived from the cDNA with the protein database showed similarity with other C. annuun PIs, and thus it was called CaTI3.


Assuntos
Capsicum , DNA Complementar , Sequência de Aminoácidos , Clonagem Molecular , Dados de Sequência Molecular , Sementes/química , Tripsina/metabolismo , Inibidores da Tripsina/química
6.
Curr Microbiol ; 62(4): 1209-17, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21170711

RESUMO

In recent years, studies have demonstrated the function of many antimicrobial peptides against an extensive number of microorganisms that have been isolated from different plant species and that have been used as models for the study of various cellular processes linked to these peptides' activities. Recently, a new defensin from Phaseolus vulgaris (L.) seeds, named PvD(1,) was isolated and characterized. PvD(1) was purified through anion exchange and phase-reverse chromatography. PvD(1)'s antifungal activity was tested. A SYTOX Green uptake assay revealed that the defensin PvD(1) is capable of causing membrane permeabilization in the filamentous fungi Fusarium oxysporum, Fusarium solani, and Fusarium laterithium and in yeast strains Candida parapsilosis, Pichia membranifaciens, Candida tropicalis, Candida albicans, Kluyveromyces marxiannus, and Saccharomyces cerevisiae at a concentration of 100 µg/ml. Ultrastructural analysis of C. albicans and C. guilliermondii cells treated with this defensin revealed disorganization of both cytoplasmic content and the plasma membrane. PvD(1) is also able to inhibit glucose-stimulated acidification of the medium by yeast cells and filamentous fungi, as well as to induce the production of reactive oxygen species and nitric oxide in C. albicans and F. oxysporum cells.


Assuntos
Antifúngicos/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Defensinas/farmacologia , Fungos/efeitos dos fármacos , Phaseolus/química , Proteínas de Plantas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Meios de Cultura/química , Fungos/metabolismo
7.
Biochim Biophys Acta ; 1810(4): 375-83, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21167915

RESUMO

BACKGROUND: A growing number of cysteine-rich antimicrobial peptides (AMPs) have been isolated from plants and particularly from seeds. It has become increasingly clear that these peptides, which include lipid transfer proteins (LTPs), play an important role in the protection of plants against microbial infection. METHODS: Peptides from Coffea canephora seeds were extracted in Tris-HCl buffer (pH 8.0), and chromatographic purification of LTP was performed by DEAE and reverse-phase HPLC. The purified peptide was submitted to amino acid sequence, antimicrobial activity and mammalian α-amylase inhibitory analyses. RESULTS: The purified peptide of 9kDa had homology to LTPs isolated from different plants. Bidimensional electrophoresis of the 9kDa band showed the presence of two isoforms with pIs of 8.0 and 8.5. Cc-LTP(1) exhibited strong antifungal activity, against Candida albicans, and also promoted morphological changes including the formation of pseudohyphae on Candida tropicalis, as revealed by electron micrograph. Our results show that Cc-LTP(1) interfered in a dose-dependent manner with glucose-stimulated, H(+)-ATPase-dependent acidification of yeast medium and that the peptide permeabilized yeast plasma membranes to the dye SYTOX green, as verified by fluorescence microscopy. Interestingly, we also showed for the first time that the well characterized LTP(1) family, represented here by Cc-LTP(1), was also able to inhibit mammalian α-amylase activity in vitro. CONCLUSIONS AND GENERAL SIGNIFICANCE: In this work we purified, characterized and evaluated the in vitro effect on yeast of a new peptide from coffee, named Cc-LPT1, which we also showed, for the first time, the ability to inhibit mammalian α-amylase activity.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Coffea/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , alfa-Amilases/antagonistas & inibidores , Sequência de Aminoácidos , Glucose/metabolismo , Humanos , Dados de Sequência Molecular , Sementes/química
8.
J Agric Food Chem ; 58(19): 10356-63, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20831249

RESUMO

Soybean toxin (SBTX) is a 44 kDa glycoprotein that is lethal to mice (LD(50) = 5.6 mg/kg). This study reports the toxicity of SBTX on pathogenic fungi and yeasts and the mechanism of its action. SBTX inhibited spore germination of Aspergillus niger and Penicillium herguei and was toxic to Candida albicans, Candida parapsilosis, Kluyveromyces marxiannus , Pichia membranifaciens, and Saccharomyces cerevisiae. In addition, SBTX hampered the growth of C. albicans and K. marxiannus and inhibited the glucose-stimulated acidification of the incubation medium by S. cerevisiae, suggesting that SBTX interferes with intracellular proton transport to the external medium. Moreover, SBTX caused cell-wall disruption, condensation/shrinkage of cytosol, pseudohyphae formation, and P. membranifaciens and C. parapsilosis cell death. SBTX is toxic to fungi at concentrations far below the dose lethal to mice and has potential in the design of new antifungal drugs or in the development of transgenic crops resistant to pathogens.


Assuntos
Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Glicoproteínas/farmacologia , Proteínas de Soja/farmacologia , Animais , Antifúngicos/toxicidade , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Fungicidas Industriais/toxicidade , Glicoproteínas/toxicidade , Humanos , Kluyveromyces/efeitos dos fármacos , Kluyveromyces/crescimento & desenvolvimento , Dose Letal Mediana , Camundongos , Penicillium/efeitos dos fármacos , Pichia/efeitos dos fármacos , Pichia/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Soja/toxicidade , Esporos Fúngicos/efeitos dos fármacos
9.
Protein Expr Purif ; 71(1): 8-15, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19948221

RESUMO

Plant defensins make up a family of cationic antimicrobial peptides with a characteristic three-dimensional folding pattern stabilized by four disulfide bridges. The aim of this work was the purification and functional expression of a defensin from cowpea seeds and the assessment of its alpha-amylase inhibitory activity. The cDNA encoding the cowpea defensin was cloned into the pET-32 EK/LIC vector, and the resulting construct was used to transform Escherichia coli cells. The recombinant peptide was purified via affinity chromatography on a Ni Sepharose column and by reverse-phase chromatography on a C2/C18 column using HPLC. N-terminal amino acid sequencing revealed that the recombinant peptide had a similar sequence to that of the defensin isolated from seeds. The natural and recombinant defensins were submitted to the alpha-amylase inhibition assay. The cowpea seed defensin was found to inhibit alpha-amylases from the weevils Callosobruchus maculatus and Zabrotes subfasciatus. alpha-Amylase inhibition assays also showed that the recombinant defensin inhibited alpha-amylase from the weevil C. maculatus. The cowpea seed defensin and its recombinant form were unable to inhibit mammalian alpha-amylases. The three-dimensional structure of the recombinant defensin was modeled, and the resulting structure was found to be similar to those of other plant defensins.


Assuntos
Bioquímica/métodos , Defensinas/isolamento & purificação , Escherichia coli/metabolismo , Fabaceae/química , Sementes/química , Gorgulhos/enzimologia , alfa-Amilases/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Defensinas/química , Defensinas/farmacologia , Eletroforese em Gel de Poliacrilamida , Ensaios Enzimáticos , Escherichia coli/efeitos dos fármacos , Fabaceae/efeitos dos fármacos , Modelos Moleculares , Dados de Sequência Molecular , Análise de Sequência de Proteína , Gorgulhos/efeitos dos fármacos
10.
Peptides ; 29(12): 2090-100, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18786582

RESUMO

The PvD1 defensin was purified from Phaseolus vulgaris (cv. Pérola) seeds, basically as described by Terras et al. [Terras FRG, Schoofs HME, De Bolle MFC, Van Leuven F, Ress SB, Vanderleyden J, Cammue BPA, Broekaer TWF. Analysis of two novel classes of plant antifungal proteins from radish (Raphanus sativus L.) seeds. J Biol Chem 1992;267(22):15301-9], with some modifications. A DEAE-Sepharose, equilibrated with 20mM Tris-HCl, pH 8.0, was initially utilized for the separation of peptides after ammonium sulfate fractionation. The basic fraction (the non-retained peak) obtained showed the presence of one unique band in SDS-Tricine gel electrophoresis with a molecular mass of approximately 6kDa. The purification of this peptide was confirmed after a reverse-phase chromatography in a C2/C18 column by HPLC, where once again only one peak was observed and denominated H1. H1 was submitted to N-terminal sequencing and the comparative analysis in databanks revealed high similarity with sequences of different defensins isolated from other plants species. The N-terminal sequence of the mature defensin isolated was used to produce a degenerated primer. This primer allowed the amplification of the defensin cDNA by RT-PCR from mRNA of P. vulgaris seeds. The sequence analysis of the cloned cDNA, named PVD1, demonstrated 314bp encoding a polypeptide of 47 amino acids. The deduced peptide presented high similarity with plant defensins of Vigna unguiculata (93%), Cicer arietinum (95%) and Pachyrhizus erosus (87%). PvD1 inhibited the growth of the yeasts, Candida albicans, Candida parapsilosis, Candida tropicalis, Candida guilliermondii, Kluyveromyces marxiannus and Saccharomyces cerevisiae. PvD1 also presented an inhibitory activity against the growth of phytopathogenic fungi including Fusarium oxysporum, Fusarium solani, Fusarium lateritium and Rizoctonia solani.


Assuntos
Antifúngicos/isolamento & purificação , DNA Complementar/metabolismo , Defensinas/farmacologia , Phaseolus/química , Sementes/química , Sequência de Aminoácidos , Antifúngicos/farmacologia , Sequência de Bases , Proliferação de Células/efeitos dos fármacos , DNA Complementar/isolamento & purificação , Defensinas/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Leveduras/efeitos dos fármacos
11.
Physiol Plant ; 131(1): 80-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18251927

RESUMO

Chitinases (EC 3.2.1.14) are hydrolytic enzymes found in different organisms. In plants, they have been described in different tissues and organs, including seeds. This study was triggered by the isolation of a 30-kDa thermostable chitinase from Adenanthera pavonina L. seeds. The enzyme was submitted to N-terminal amino acid sequencing, and the analysis revealed a high degree of homology with class III chitinases. Bidimensional electrophoresis of the 30-kDa band showed the presence of three isoforms with pIs of 5.2, 5.5 and 5.8. A chitinase was also found in exudates released from the same seeds, which was seen to be immunorelated to the above 30-kDa protein. It was also submitted to N-terminal amino acid sequencing and seen as highly homologous to class III chitinases. In addition, the expression of chitinases during A. pavonina L. seed germination and seedling development was investigated. Seeds were allowed to germinate in the absence of light for approximately 5 days and were grown, for different times, in the absence or presence of light. After each seedling developmental time, samples of exudates, roots and cotyledonary leaves were collected and submitted to protein extraction. The presence of proteins immunorelated to the 30-kDa chitinase was detected in all analyzed samples. Further analyses showed that light significantly interfered with the chitinase expression in some organs. The tissue and subcellular chitinase location in seedling roots was also investigated, and it was majorly localized in the cell wall and in the intercellular spaces of the root hair zone.


Assuntos
Quitinases/metabolismo , Fabaceae/enzimologia , Proteínas de Plantas/metabolismo , Plântula/enzimologia , Sequência de Aminoácidos , Western Blotting , Quitinases/química , Quitinases/genética , Cotilédone/enzimologia , Cotilédone/genética , Cotilédone/metabolismo , Bases de Dados Genéticas , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Fabaceae/genética , Fabaceae/ultraestrutura , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Plântula/genética , Plântula/metabolismo , Sementes/enzimologia , Sementes/genética , Sementes/metabolismo , Homologia de Sequência de Aminoácidos , Temperatura
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