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2.
Sci Rep ; 11(1): 8643, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883589

RESUMO

The green synthesis of NPs through plant extracts can be a modest, one-pot alternative synthesis to the conventional physical or chemical method. The prime focus of this study is to produce MNPs by the reducing effect of Bauhinia tomentosa leaf extract, and it was immobilized in porcine pancreatic lipase (PPL). Synthesized NPs were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and Raman spectroscopy, UV-Vis Spectrometry, Thermogravimetry, and Differential Scanning Calorimeter (DSC), Zeta potential test, VSM, BET and Fourier Transform Infrared Spectroscopy (FTIR). The effect of process parameters was studied, about the efficiency of immobilization are enzyme stability, the extent of enzyme reusability, its separation from products, the activity of immobilized enzyme, recovery, and its loss. Finally, the immobilized lipase was used for the synthesis of 1,3-diolein using enzyme-mediated esterification of oleic acid and glycerol. Under optimized condition (reaction temp-55 [Formula: see text]C; molar ratio-2.5:1; pH-7) diolein yield was achieved to be 94%. Therefore, this work was further used for the industrial production of 1,3-diacylglycerol since a perfect enzyme-catalyzed process was observed.

3.
Int J Biol Macromol ; 147: 493-498, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954262

RESUMO

Fibrous hemostat was produced using wet laying technique comprising of acid and water soluble chitosan with fibrous cellulose. The hemostatic efficiency and their structural properties were evaluated using blood clotting time, whole blood adhesion and analytical characterization techniques. The maximum concentration of chitosan utilised for the production of nonwoven was 1.5 w/v % upon which increased the viscosity of the solution. The absorption of phosphate buffer solution was found to be 1117% for acid soluble chitosan based nonwoven whereas for water soluble chitosan based nonwoven was 997%. Increased red blood cells and platelets were found to be higher in acid soluble chitosan compared to water soluble chitosan based cellulose nonwoven. The blood clotting time for acid soluble chitosan nonwoven was found to be 166 s and water soluble chitosan nonwoven was 170 s. The developed hemostat have potential application in reducing blood loss and also inducing the blood coagulation pathway which was confirmed by the adhesion of platelets on to the surface of nonwoven web.


Assuntos
Celulose/química , Quitosana/química , Hemostáticos/química , Água/química , Hemorragia/tratamento farmacológico , Humanos
4.
Comput Biol Chem ; 72: 181-191, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29329783

RESUMO

Plant secondary metabolites are widely used in human disease treatment; though primary metabolism provides precursors for secondary metabolism, not much has been studied to unravel the link connecting both the processes. Most common form of gene regulation interconnecting diverse metabolism occurs at the transcriptional and/or posttranscriptional level mediated by regulatory cis-elements. The present study aims at understanding the common cis-elements network connecting the major primary metabolic enzyme, cell wall invertase (CWIN) and secondary metabolism genes in Nicotiana benthamiana (N. benthamiana). The CWIN and thirty one other gene sequences were extracted from N. benthamiana genome, followed by cis-element analysis of their 5' upstream and 3' downstream region using different programs (Genomatix software suite; PLACE and PlantCARe). Comparative cis-element analysis of CWIN (N. benthamiana and other plant species) and other primary, secondary metabolism and transcription factor genes (N. benthamiana) revealed the occurrence of common stress associated cis-elements. Predominantly, AHBP, L1BX, MYBL, MADS, MYBS, GTBX, DOFF and CCAF were found in the 5' upstream region of all genes, whereas AHBP, MYBL, L1BX, HEAT, CCAF and KAN1 were largely occurring in the 3' downstream region of all genes; indicating common function of these elements in transcriptional and posttranscriptional gene regulation. Further, genomic analysis using FGENESH, GenScan and homology based methods (BlastX and BlastN) was performed on the N. benthamiana contigs harboring CWIN and PAL, in an attempt to identify genomic neighborhood genes. The 5' upstream and 3' downstream region of genes in the genomic neighborhood of CWIN and PAL were also subjected to similar cis-element analysis, and the results indicated cis-elements profile similar to CWIN, PAL and other primary, secondary metabolism and transcription factor genes. The results of evolutionary studies confirmed that the 5' upstream region of NbCWINs significantly showed more proximity to secondary metabolism genes 4CL and the redox gene SOD, followed by the phenylpropanoid pathway gene CHI. The 3' downstream regions of NbCWINs were more closely related to other plant CWINs, followed by the redox gene, SOD and primary metabolism gene FBA. Thus, the commonly found stress responsive cis-elements in our study can play a vital role in modulating key pathways of both primary and secondary metabolism; thereby postulating their role in regulating plant growth and metabolisms under unfavourable growth conditions.


Assuntos
Genes de Plantas/genética , Fenilalanina Amônia-Liase/genética , Proteínas de Plantas/genética , Elementos Reguladores de Transcrição , beta-Frutofuranosidase/genética , Simulação por Computador , Evolução Molecular , Nicotiana/enzimologia
5.
Int Braz J Urol ; 41(3): 503-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26200543

RESUMO

PURPOSE: Calcium oxalate urolithiasis is one of the most common urinary tract diseases and is of high prevalence. The present study proposes to evaluate the antilithiatic property of hydrogen sulfide and its metabolites like thiosulfate & sulfate in an in vitro model. MATERIALS AND METHODS: The antilithiatic activity of sodium hydrogen sulfide (NaSH), sodium thiosulfate (Na(2)S(2)O(3)) and sodium sulfate (Na(2)SO(4)) on the kinetics of calcium oxalate crystal formation was investigated both in physiological buffer and in urine from normal and recurrent stone forming volunteers. The stones were characterized by optical and spectroscopic techniques. RESULTS: The stones were characterized to be monoclinic, prismatic and bipyramidal habit which is of calcium monohydrate and dihydrate nature. The FTIR displayed fingerprint corresponding to calcium oxalate in the control while in NaSH treated, S=O vibrations were visible in the spectrum. The order of percentage inhibition was NaSH>Na(2)S(2)O(3)>Na(2)SO(4). CONCLUSION: Our study indicates that sodium hydrogen sulfide and its metabolite thiosulfate are inhibitors of calcium oxalate stone agglomeration which makes them unstable both in physiological buffer and in urine. This effect is attributed to pH changes and complexing of calcium by S(2)O(3)(2)-and SO(4)(2)- moiety produced by the test compounds.


Assuntos
Oxalato de Cálcio/metabolismo , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/metabolismo , Urolitíase/metabolismo , Urolitíase/prevenção & controle , Adulto , Análise de Variância , Oxalato de Cálcio/química , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Urina/química
6.
Int. braz. j. urol ; 41(3): 503-510, May-June 2015. ilus
Artigo em Inglês | LILACS | ID: lil-755866

RESUMO

ABSTRACTPurpose:

Calcium oxalate urolithiasis is one of the most common urinary tract diseases and is of high prevalence. The present study proposes to evaluate the antilithiatic property of hydrogen sulfide and its metabolites like thiosulfate & sulfate in an in vitro model.

Materials and Methods:

The antilithiatic activity of sodium hydrogen sulfide (NaSH), sodium thiosulfate (Na2S2O3) and sodium sulfate (Na2SO4) on the kinetics of calcium oxalate crystal formation was investigated both in physiological buffer and in urine from normal and recurrent stone forming volunteers. The stones were characterized by optical and spectroscopic techniques.

Results:

The stones were characterized to be monoclinic, prismatic and bipyramidal habit which is of calcium monohydrate and dihydrate nature. The FTIR displayed fingerprint corresponding to calcium oxalate in the control while in NaSH treated, S=O vibrations were visible in the spectrum. The order of percentage inhibition was NaSH>Na2S2O3>Na2SO4.

Conclusion:

Our study indicates that sodium hydrogen sulfide and its metabolite thiosulfate are inhibitors of calcium oxalate stone agglomeration which makes them unstable both in physiological buffer and in urine. This effect is attributed to pH changes and complexing of calcium by S2O32-and SO42- moiety produced by the test compounds.

.


Assuntos
Adulto , Feminino , Humanos , Masculino , Oxalato de Cálcio/metabolismo , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/metabolismo , Urolitíase/metabolismo , Urolitíase/prevenção & controle , Análise de Variância , Estudos de Casos e Controles , Oxalato de Cálcio/química , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Urina/química
7.
Indian J Pharm Sci ; 76(4): 370-4, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25284936

RESUMO

Novel bicyclo[3.3.1]nonane derivatives were synthesized by an efficient methodology from acetoacetanilide, 2-methoxy and 4-methoxyacetoacetanilides, 1,3,5-trinitrobenzene and triethylamine. The structures of the compounds were characterized by UV/Visible, FTIR, (1)H NMR and 2D-correlation spectroscopy analysis. The in vitro cytotoxic studies were performed using Ehrlich Ascites Carcinoma cell line by Trypan blue dye exclusion assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay. The IC50 values of the 8-(4'-/2'-methoxy/unsubstituted phenylcarbamoyl)bicyclo[3.3.1]nonanes were found to be 110.65 µg/ml, 148.23 µg/ml and 151.71 µg/ml, respectively. Thus (4-methoxyphenylcarbomyl)bicyclo[3.3.1]nonane was more potent compared to other two bicyclic adducts.

8.
Colloids Surf B Biointerfaces ; 102: 288-91, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23006568

RESUMO

The present work focuses the use of the aqueous extract of Alternanthera sessilis Linn. (Amaranthaceae) in producing silver nanoparticles (AgNPs) from silver nitrate aqueous. Phytochemical analysis of the extract revealed the presence of alkaloid, tannins, ascorbic acid, carbohydrates and proteins and they serve as effective reducing and capping agents for converting silver nitrate into nanoparticles. The synthesized silver nanoparticles (AgNPs) were also tested for proteins and ascorbic acid. Its pH was also determined (5.63). The AgNPs obtained was characterized by UV-vis spectroscopy, FT-IR spectroscopy, SEM, Zeta sizer and TG-DSC. SEM images which revealed the presence of various shapes and sizes. FT-IR spectrum showed the AgNPs having a coating of proteins indicating a dual role of bio-molecules responsible for capping and efficient stabilization of the silver nanoparticles. Presence of impurities and melting point profile were screened by TG-DSC analyzer. AgNPs were synthesized from the silver nitrate through the reducing power of ascorbic acid present in A. sessilis leaves. In this study, we also investigated antimicrobial and antioxidant activity of green synthesized AgNPs. The antimicrobial activity is investigated by Bauer et al.'s method. Antioxidant activity was done by DPPH method.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Nanopartículas Metálicas/química , Prata/química , Anti-Infecciosos/farmacologia , Ácido Ascórbico/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Nanotechnology ; 23(46): 465603, 2012 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-23095367

RESUMO

Self-assembly of pristine multi-walled carbon nanotubes (CNTs) in aqueous dispersion using a protein, bovine serum albumin (BSA), has been demonstrated. Step-wise conformational changes in BSA as a function of temperature have been deployed to direct the assembly of nanotubes. More specifically, CNTs distributed randomly in native BSA at 35 °C as well as completely denatured BSA solution at 80 °C self-assemble in the intermediate temperature range of 45-65 °C, as evident from scanning and transmission electron microscopy. Fourier transform infrared (FTIR) and fluorescence studies indicate significant changes in the α-helical content of the protein with respect to the amide I and II bands and tryptophan emission intensity, respectively. The stability of CNT dispersion in BSA solution has been attributed to the hydrophobic interaction between nanotubes and the protein molecule by adding sodium cholate to the dispersion. Moreover, a mechanism based on electrostatic repulsion between BSA-bound CNTs has been proposed for the thermally reversible assembly of CNTs in BSA solution based on evidence from zeta potential measurements and FTIR spectroscopy. Thus the present report demonstrates bio-mimetic self-assembly of as-synthesized CNTs using changes in surface charge and conformation of an unfolding protein for biomedical applications and nanobiotechnology.


Assuntos
Nanotecnologia/métodos , Nanotubos de Carbono/química , Proteínas/química , Animais , Fenômenos Bioquímicos , Bovinos , Nanotubos de Carbono/ultraestrutura , Desnaturação Proteica , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
11.
Singapore Med J ; 50(3): 300-2, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19352575

RESUMO

INTRODUCTION: This study was designed to scientifically evaluate the effects of an aqueous extract of Muntingia calabura L. (M. calabura), a medicinal herb, on isoproterenol-induced myocardial infarction (MI) in rat models. METHODS: Six groups of Wistar albino rats, each comprising six animals, were selected for this study. Group I served as a control, Group II rats were given isoproterenol (20 mg/100g, subcutaneously), and Group III rats were given M. calabura leaf extract (300 mg/kg). Groups IV, V and VI rats were given M. calabura leaf extract (100 mg/kg, 200 mg/kg and 300 mg/kg, respectively) and isoproterenol (20 mg/100g subcutaneously) prior to MI induction. The transaminases (aspartate transaminase and alanine transaminase), lactate dehydrogenase (LDH) and creatine phosphokinase (CK), were estimated in both the serum and heart tissues, and the serum uric acid level was also estimated. RESULTS: Isoproterenol significantly increased the activities of CK, LDH and the transaminases in serum with a concomitant decrease in these enzymes in tissue. Pretreatment with the aqueous leaf extract of M. calabura at a dose of 300 mg/kg body weight for 30 days had a significant effect on the activities of marker enzymes compared to the other groups. Serum uric acid level, which increased on isoproterenol administration, registered near normal values on treatment with the leaf extract under study. CONCLUSION: The study confirms the protective effects of M. calabura leaf extract against isoproterenol-induced biochemical alterations in rats.


Assuntos
Medicina Herbária , Isoproterenol/efeitos adversos , Infarto do Miocárdio/induzido quimicamente , Miocárdio , Extratos Vegetais/farmacologia , Simpatomiméticos/efeitos adversos , Alanina Transaminase , Animais , Aspartato Aminotransferases , Estudos de Casos e Controles , Humanos , Masculino , Modelos Animais , Infarto do Miocárdio/tratamento farmacológico , Ratos , Ratos Wistar , Ácido Úrico/sangue
12.
Cancer Res ; 62(11): 3271-5, 2002 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12036944

RESUMO

We have found a significant concordance between the in vitro replication errors of human DNA polymerase beta and in vivo point mutations of the adenomatous polyposis coli (APC) gene that leads to colon cancer. We determined the error spectrum of DNA polymerase beta in the human APC gene under PCR conditions and compared it with the set of mutations reported in human colon tumors. Polymerase beta created seven hotspot mutations within 141 target bp analyzed in APC exon 15. Three of these polymerase beta hotspots, 2 frameshifts and a bp substitution mutation, were concordant with 3 of 13 APC hotspots detected in human colon cancers in the same DNA sequences. These 3 concordant hotspots accounted for some 54% of reported in vivo APC hotspot mutations. Using the assumption of a hypergeometric distribution of hotspot mutations among bp of the scanned sequences, the probability of this concordance occurring by chance is <4 x 10(-4). These data support the hypothesis that DNA polymerase beta errors are an important fraction of cancer-causing APC mutations.


Assuntos
Neoplasias do Colo/genética , DNA Polimerase beta/genética , Replicação do DNA/genética , Genes APC , DNA de Neoplasias/biossíntese , DNA de Neoplasias/genética , Humanos , Mutação Puntual
13.
Fitoterapia ; 73(2): 160-4, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11978432

RESUMO

The aqueous, methanol, chloroform and hexane extracts of Swertia corymbosa were tested (in vitro) for their antimicrobial efficiency. Maximum inhibitory activity was noticed against Staphylococcus aureus and Salmonella typhi.


Assuntos
Anti-Infecciosos/farmacologia , Gentianaceae , Fitoterapia , Extratos Vegetais/farmacologia , Salmonella typhi/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos , Aspergillus/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
14.
J Ethnopharmacol ; 79(1): 129-32, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11744306

RESUMO

Phytochemical investigation of the various extracts of the leaves of Begonia malabarica Lam. (Begoniaceae) resulted in the isolation and identification of six known compounds, viz. friedelin, epi-friedelinol, beta-sitosterol, luteolin, quercetin and beta-sitosterol-3-beta-D-glucopyranoside. The aqueous and organic solvent extracts were also tested against ten human pathogenic bacteria and four fungal strains by the agar-well diffusion method. All the extracts were devoid of antifungal activity against the tested fungi. The hexane extract did not show any activity. The aqueous extracts showed activity against the Gram-negative bacteria except Vibrio parahaemolyticus. The chloroform and methanol extracts showed activity against all the tested bacteria. The study supported the claim of the usefulness of the plant in respiratory tract infections and also suggests its use in diarrhoea and skin diseases caused by pathogenic bacteria.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Extratos Vegetais/farmacologia , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Humanos , Índia , Testes de Sensibilidade Microbiana
16.
Fitoterapia ; 72(4): 409-11, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11395265

RESUMO

The methanol extract of Bridelia crenulata stem bark (50-1.5625 mg/ml) and its isolated luteoforol (2-0.25 mg/ml) showed concentration-dependent inhibiting activity against all 10 tested bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Benzopiranos/farmacologia , Euphorbiaceae , Plantas Medicinais , Benzopiranos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Caules de Planta
17.
Anc Sci Life ; 20(1-2): 82-4, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22557002

RESUMO

The water extract of poochendurappattai was screened for antitumour activity at the doss of 5mg, 10mg, 20mg and 50 mg/kg body weight in rats against methylcholanthrene induced fibrosarcoma. There was 63% regression in the tumour weight at the doses of 10mg and 20 mg/kg body weight. This antitumour activity may be due to compounds like royaleanones since royaleanones are known to possess anticancer activity. Te phytochemical investigation of poochendurappattai revealed the presence of royaleanones.

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