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1.
Environ Monit Assess ; 196(6): 552, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755295

RESUMO

The TiO2 nanocomposite efficiency was determined under optimized conditions with activated carbon to remove ammoniacal nitrogen (NH3-N) from the leachate sample. In this work, the facile impregnation and pyrolysis synthesis method was employed to prepare the nanocomposite, and their formation was confirmed using the FESEM, FTIR, XRD, and Raman studies. In contrast, Raman phonon mode intensity ratio ID/IG increases from 2.094 to 2.311, indicating the increase of electronic conductivity and defects with the loading of TiO2 nanoparticles. The experimental optimal conditions for achieving maximum NH3-N removal of 75.8% were found to be a pH of 7, an adsorbent mass of 1.75 mg/L, and a temperature of 30 °C, with a corresponding time of 160 min. The experimental data were effectively fitted with several isotherms (Freundlich, Hill, Khan, Redlich-Peterson, Toth, and Koble-Corrigan). The notably elevated R2 value of 0.99 and a lower ARE % of 14.61 strongly support the assertion that the pseudo-second-order model compromises a superior depiction of the NH3-N reduction process. Furthermore, an effective central composite design (CCD) of response surface methodology (RSM) was employed, and the lower RMSE value, precisely 0.45, demonstrated minimal disparity between the experimentally determined NH3-N removal percentages and those predicted by the model. The subsequent utilization of the desirability function allowed us to attain actual variable experimental conditions.


Assuntos
Carvão Vegetal , Nitrogênio , Titânio , Poluentes Químicos da Água , Titânio/química , Nitrogênio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Carvão Vegetal/química , Amônia/química , Adsorção , Modelos Químicos , Eliminação de Resíduos Líquidos/métodos , Nanocompostos/química
2.
Explor Target Antitumor Ther ; 4(2): 208-216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205316

RESUMO

Tannins are secondary metabolites that belong to the family of polyphenolic compounds and have gained a huge interest among researchers due to their versatile therapeutic potential. After lignin, these are the second most abundant polyphenols found in almost every plant part like stem, bark, fruit, seed, leaves, etc. Depending upon their structural composition, these polyphenols can be divided into two distinct groups, namely condensed tannins and hydrolysable tannins. Hydrolysable tannins can be further divided into two types: gallotannins and ellagitannins. Gallotannins are formed by the esterification of D-glucose hydroxyl groups with gallic acid. The gallolyl moieties are bound by a depside bond. The current review focuses mainly on the anti-carcinogenic potential of recently discovered gallotannins, ginnalin A, and hamamelitannin (HAM). Both of these gallotannins possess two galloyl moieties linked to a core monosaccharide having anti-oxidant, anti-inflammatory, and anti-carcinogenic abilities. Ginnalin A is found in plants of the genus Acer whereas HAM is present in witch hazel plants. The biosynthetic pathway of ginnalin A along with the mechanism of the anti-cancer therapeutic potential of ginnalin A and HAM has been discussed. This review will certainly help researchers to work further on the chemo-therapeutic abilities of these two unique gallotannins.

3.
Biotechnol Appl Biochem ; 70(4): 1439-1449, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36965069

RESUMO

Condensed and hydrolyzable tannins are secondary metabolites present in almost every plant part. Tannase enzyme acts on hydrolyzable tannins to produce gallic acid and tannase-mediated end-products with immense therapeutic potential. Seven different fruits with significant presence of hydrolyzable tannin content were selected to check for phenol, tannin, and hydrolyzable tannin contents. Prunus domestica had the maximum phenol content, that is, 85.4 ± 0.207, followed by Syzygium cumini, Fragaria ananassa, Rubus fruticosus, and Psidium guajava. Plum showed the maximum number of hydrolyzable tannins. Fruit extracts were subjected to tannase hydrolysis and their antimicrobial and antioxidant activities were determined. There was a significant increase in the antioxidant abilities of the fruits with Punica granatum extract, displaying the highest decline of 132 units of IC50 followed by F. ananassa hydrolyzable extract, showing a decrease from 224.75 to 119.98 µg/mL. The extracts also depicted a significant increase in antibacterial activity after hydrolysis against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus with Rubus idaeus aqueous extract observed to be most effective against E. coli. The increase in antioxidant and antibacterial activity can be attributed to the production of tannase-mediated products formed after the biotransformation of hydrolyzable tannins present in the aqueous extracts.


Assuntos
Taninos Hidrolisáveis , Taninos , Taninos/farmacologia , Taninos/metabolismo , Taninos Hidrolisáveis/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Frutas/metabolismo , Hidrolases/metabolismo , Escherichia coli/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Fenóis/análise , Antibacterianos/farmacologia , Biotransformação
4.
Int J Biol Macromol ; 233: 123575, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36764347

RESUMO

Polyhydroxybutyrate (PHB) has significant potential for replacing non-biodegradable traditional plastic, which is responsible for several global environmental issues. The main problem with switching to bio-based alternatives for petrochemical plastics is the large price gap on the market. To overcome this problem, the present research was focused on the utilization of inexpensive substrates i.e. agricultural residues for cost-effective PHB production by endospore-forming bacteria Bacillus badius MTCC 13004. For efficient PHB production, Box-Behnken Design (BBD) was selected for media optimization and to observe the interactive effects of four variables i.e. pH, Na acetate, Banana peel, and mustard cake. PHB yield of 2.11 g/L was attained under optimized conditions compared to non-optimized conditions (0.72 g/L). FTIR spectra analysis of PHB extracted from Bacillus badius was found to be similar to commercial PHB. NMR data was also matched with the chemical shift signals CH, CH2, and CH3 of PHB. The melting temperature (Tm) and glass transition temperature (Tg) of PHB from Bacillus badius was found to be 165.14 and 2.68 °C, respectively. Further, PCR protocol was also designed to amplify key enzymes of the PHB synthesis pathway i.e. PHB synthase (phb C gene).


Assuntos
Bacillus , Análise Custo-Benefício , Bacillus/metabolismo , Plásticos/metabolismo , Hidroxibutiratos/química , Poliésteres/química
5.
Nat Prod Res ; 37(22): 3889-3895, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36525418

RESUMO

Thirty-five distinct endophytic fungi were isolated from the roots of Asparagus racemosus. Five out of 35 isolates were found to be efficient saponins producers and they were identified as Aspergillus terreus (E.F-1), Aspergillus flavus (E.F-7), Penicillium sp. (E.F-12), Talaromyces pinophilus(S-26), and Aspergillus terreus (Y-2) based on 18 sr RNA sequencing. The crude extracts of endophytic fungi were screened using High-performance liquid chromatography (HPLC) for quantitative analysis of saponin. The crude extracts of endophytic fungi were also characterised using FT-IR spectroscopy and mass spectrometry. The IR spectra of all five endophytic fungi crude extracts revealed the presence of -OH,-CH Alkyl,-CH3,-C-O-C,-C=C,-C=O stretching, which indicated the presence of saponin. Eight types of saponins recognised by mass spectrometry were Cyclamine saponin, Aspoligonin A, Sarsapogenin, Asparacosin A, Schidigera saponinD5, Aspargoside A, Dioscin, and Protodioscin. Endophytic fungi extracts also exhibited antimicrobial activity and antioxidant activity.

6.
Environ Res ; 212(Pt B): 113337, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35469857

RESUMO

Herein, we report a bacteria-based strategy as an efficient, reasonable, benign, and promising methodology for remediating heavy metals fed waterbodies. The contemporary study deals with isolating, screening, and characterizing heavy metal resistive bacteria from metal-rich sites. The transcriptome analysis reveals the identity of the isolated species as Bacillus pumilus and Bacillus cereus. Batch studies put forth the bioremoval results in designed conditions of different pH, concentration, dose, and time. The mechanistic actions are drawn using complementary techniques such as Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The theory of surface adsorption of lead (Pb(II)) and nickel (Ni(II)) is further fostered by the application of adsorption isotherms. The conducted studies establish the bacterial morphological stratagems and multifarious biochemical approaches for countering metallic ions of Pb(II) and Ni(II). The exhibition of significant removal results by the isolated bacterial strains in simulated water samples with remarkable proliferation rates has opened up its favorability for industrial platforms.


Assuntos
Bacillus pumilus , Metais Pesados , Poluentes Químicos da Água , Adsorção , Bacillus cereus/genética , Concentração de Íons de Hidrogênio , Íons , Cinética , Chumbo , Metais Pesados/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
7.
Ecotoxicol Environ Saf ; 208: 111484, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120265

RESUMO

Industrial wastes, for instance, tannery wastes are rich soups of resistant and bioremediation-potent bacteria. In the present work, Chromium (Cr) and tannic acid (TA) resistance bacterial strains were isolated from tannery effluent and identified as Bacillus subtilis (MCC 3275) and Bacillus safensis (MCC 3283) based on its 16S Ribosomal RNA homology. Hexavalent Cr is highly toxic and mutagenic due to its high mobility and reactivity. Whereas, TA is known to inhibit enzyme activity, substrate deprivation, and interaction with membranes and matrix-metal ions. The developed In vitro co-cultured microcosm of B. subtilis and B. safensis was able to remove Cr(VI) up to 95% and TA up to 23%. The bacteria cultures separately were able to degrade Cr(VI) to 88% by B. subtilis and 91% by B. safensis and TA up to 27%. Plackett Burman design (PBD) followed by Response surface methodology (RSM) was applied for the optimization of physio-chemical parameters. The optimized conditions for co-culture development were recorded as K2HPO4 = 0.2 g/L, MgSO4 = 0.2 g/L, NH4Cl = 0.5 g/L, glucose - 0.2 g/L, TA - 5%, Cr = 200 ppm, incubation period of 96 h, agitation speed of 110 rpm, pH = 5.0, temperature= 30 °C and inoculum size = 3%. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) revealed the thorough mechanism of cellular uptake followed by degradation of Cr(VI) and TA. The efficiency of co-culture for other heavy metals was observed as follows: Zn 65%, Pb 63%, Cd 65%, and Ni 65%. Bioremediation using bacteria is an economical and environmentally better alternative to conventional remediation methods. The isolated bacteria are useful in the effluent treatment of tannery or related industries and in metal recovery in mining processes.


Assuntos
Bacillus subtilis/metabolismo , Bacillus/metabolismo , Cromo/metabolismo , Taninos/metabolismo , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/prevenção & controle , Biodegradação Ambiental , Resíduos Industriais/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-31223096

RESUMO

BACKGROUND: Among the various phenolics metabolites, ferulic acid is considered as the promising mitigating, restorative and antioxidant agent. Ferulic acid is one of the most commonly found natural products in vegetables, for example, tomatoes, sweet corn, and in rice grain. Phytochemicals are utilized in the treatment of human ailments and these are derived from the dietary compounds. OBJECTIVE: The present review widely argued the calming restorative capability of ferulic acid alongside the scientific evidences and its proposed mechanism for activity. Furthermore, we provided the main practical points for the use of ferulic acid in oxidative damages during various diseases. Additionally, the relevant patents on ferulic acid with various therapeutic potential has been discussed. METHODS: The approach consisted of searching several resources, including theses, technical reports, web-based scientific databases such as publications on PubMed, ScienceDirect, Springer, PROTA, Google Scholar, and other allied databases. Thus, recent patent regarding the role of ferulic acid therapeutic potenitial has been discussed. RESULTS: One hundred and twenty references have been cited in the present review article. The cited references were found to be suitable and described the therapeutic application of ferulic acid thoroughly. CONCLUSION: Ferulic acids are known to contrarily down-manage an assortment of extracellular and intrcelullular molecular targets related to infection movement. Various patents on ferulic acid based moieties have been accounted for from 2018. The ferulic acids have a wide scope of impacts against different infections like malignant growth, diabetes, cardiovascular and neurodegenerative diseases. The current review deals with the antioxidant property of ferulic acid and the recent patent describes the role of ferulic acid against human diseases.


Assuntos
Antioxidantes/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Ácidos Cumáricos/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Animais , Humanos , Peroxidação de Lipídeos , Oxirredução , Patentes como Assunto , Verduras
9.
Diagn Microbiol Infect Dis ; 93(2): 96-100, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30314653

RESUMO

Carbapenemase-producing organisms have been an immense public health problem in recent years. Combined disc test (CDT) is a simple and widely used phenotypic method for carbapenemase detection, especially in developing countries. This study evaluates the performance of modified combined disc test (mCDT), a novel and 4 times cheaper method than CDT. In total, 572 (15.5%) Klebsiella spp. including 81 (14.2%) carbapenemase producers were isolated from 3993 clinical samples. Both mCDT and CDT showed similar sensitivity, specificity, positive predictive value, and negative predictive value for the differentiation of Class A, B, and D carbapenemase-producing Klebsiella spp.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Klebsiella/efeitos dos fármacos , Klebsiella/enzimologia , Testes de Sensibilidade Microbiana/métodos , beta-Lactamases/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Humanos , Klebsiella/classificação , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes
11.
Water Environ Res ; 90(5): 424-430, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29678213

RESUMO

This study was carried out to analyze the heavy metals biosorption potential of bacteria isolated from soil contaminated with electroplating industrial effluents. Bacterial isolates were screened for their multi-metal biosorption potential against copper, nickel, lead, and chromium. Bacterial isolate CU4A showed the maximum uptake of copper, nickel, lead, and chromium in aqueous solution, with a biosorption efficiency of 87.16 %, 79.62%, 84.92%, and 68.12%, respectively. The bacterial strain CU4A was identified as Bacillus cereus, following 16S rRNA gene sequence analysis. The surface chemical functional groups of bacterial biomass were identified by Fourier transform infrared (FTIR) spectroscopy as hydroxyl, carboxyl, amine, and halide, which may be involved in the biosorption of heavy metals. Analysis with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) confirmed the adsorption of metals on the bacterial cell mass. The results of this study are significant and could be further investigated for the removal of heavy metals from contaminated environments.


Assuntos
Bacillus cereus/metabolismo , Poluição Ambiental/prevenção & controle , Metais Pesados/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Adsorção , Recuperação e Remediação Ambiental , Microscopia Eletrônica de Varredura , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de RNA , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
12.
J Clin Lab Anal ; 32(7): e22448, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29603371

RESUMO

BACKGROUND: The aim of this study was to evaluate the modified Carba NP test to differentiate KPC (Klebsiella pneumoniae carbapenemase)- and MBL (metallo-ß-lactamase)-producing Klebsiella species. METHODS: A total of 508 non-duplicate clinical isolates of Klebsiella spp. were processed by modified Carba NP and combined disc tests which were further confirmed by conventional polymerase chain reaction (PCR), a gold standard method for statistical analysis. RESULTS: Modified Carba NP test demonstrated 91.7% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 99.8% negative predictive value (NPV) for KPC and 96.7%, 100%, 100%, and 99.5% for MBL detection, respectively. CONCLUSION: The performance of modified Carba NP test was significantly better than combined disc test, fulfilling the requirement of simple and rapid test for clinical applications.


Assuntos
Proteínas de Bactérias/genética , Klebsiella/classificação , Klebsiella/enzimologia , Tipagem Molecular/métodos , Resistência beta-Lactâmica/genética , beta-Lactamases/genética , Klebsiella/efeitos dos fármacos , Klebsiella/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
13.
Mini Rev Med Chem ; 18(15): 1283-1293, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29600764

RESUMO

Gallic acid and its derivatives not only exhibit excellent antioxidant, anticarcinogenic, antimutagenic, antimicrobial properties but also provide protection to the cells against oxidative stress. Gallic acid (3, 4, 5-trihydroxybenzoic acid), a low molecular triphenolic compound emerged as an efficient apoptosis inducing agent. The antimicrobial and other biological properties of gallic acid and its derivatives seemed to be linked with the hydrolysis of ester linkage between gallic acid and polyols like tannins hydrolyzed after ripening of many edible fruits. Gallic acid serves a natural defense mechanism against microbial infections and modulation of immune responses. The current review updates us with the diverse roles played by gallic acid, its antioxidant potential, action mechanism and more importantly the diverse array of applications in therapeutic and pharmaceutical areas.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Ácido Gálico/química , Hipoglicemiantes/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Diabetes Mellitus/patologia , Diabetes Mellitus/prevenção & controle , Ácido Gálico/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia
14.
PLoS One ; 13(1): e0190729, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29300775

RESUMO

Mutations in gyrA are the primary cause of quinolone resistance encountered in gram-negative clinical isolates. The prospect of this work was to analyze the role of gyrA mutations in eliciting high quinolone resistance in uropathogenic E.coli (UPEC) through molecular docking studies. Quinolone susceptibility testing of 18 E.coli strains isolated from UTI patients revealed unusually high resistance level to all the quinolones used; especially norfloxacin and ciprofloxacin. The QRDR of gyrA was amplified and sequenced. Mutations identified in gyrA of E.coli included Ser83Leu, Asp87Asn and Ala93Gly/Glu. Contrasting previous reports, we found Ser83Leu substitution in sensitive strains. Strains with S83L, D87N and A93E (A15 and A26) demonstrated norfloxacin MICs ≥1024mg/L which could be proof that Asp87Asn is necessary for resistance phenotype. Resistance to levofloxacin was comparatively lower in all the isolates. Docking of 4 quinolones (ciprofloxacin, ofloxacin, levofloxacin and norfloxacin) to normal and mutated E.coli gyrase A protein demonstrated lower binding energies for the latter, with significant displacement of norfloxacin in the mutated GyrA complex and least displacement in case of levofloxacin.


Assuntos
Antibacterianos/farmacologia , DNA Girase/genética , Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Quinolonas/farmacologia , Escherichia coli Uropatogênica/genética , DNA Girase/metabolismo , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Mutação , Homologia de Sequência do Ácido Nucleico , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/metabolismo
15.
AMB Express ; 7(1): 201, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29138995

RESUMO

A chromium and tannic acid resistance fungal strain was isolated from tannery effluent, and identified as Aspergillus niveus MCC 1318 based on its rDNA gene sequence. The MIC (minimum inhibitory concentration) of the isolate against chromium and tannic acid was found to be 200 ppm and 5% respectively. Optimization of physiochemical parameters for biosorption of chromium and tannic acid degradation was carried out by Plackett-Burman design followed by response surface methodology (RSM). The maximum chromium removal and tannic acid degradation was found to be 92 and 68% respectively by A. niveus. Chromium removal and tannic acid degradation was increased up to 11 and 6% respectively after optimization. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) was used to investigate biosorption phenomena.

16.
Nucleosides Nucleotides Nucleic Acids ; 36(8): 543-551, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28854118

RESUMO

In order to explore the biological potential, some synthesized triazolylnucleosides were evaluated for their antibacterial, tyrosinase and DNA photocleavage activities. Triazolylnucleosides (5-12) were screened against Staphylococcus aureus (ATCC 6538), gram-positive and Escherichia coli (ATCC 10536), gram-negative bacterial strains. Among the series, compound 9 exhibited a significant level of antibacterial activity against both strains at higher concentration in reference to the standard drug, Levofloxacin. Tyrosinase activity and inhibition of these compounds were also studied, and it has been found that compounds 8 and 11 displayed more than 50% inhibitory activity. In addition, six compounds (7-12) were evaluated for their DNA photocleavage activity. The compounds 8 and 12 exhibited excellent DNA photocleavage activity at a concentration of 10 µg and may be used as template for antitumor drugs in the future.


Assuntos
Clivagem do DNA/efeitos dos fármacos , Luz , Monofenol Mono-Oxigenase/antagonistas & inibidores , Nucleosídeos/química , Nucleosídeos/farmacologia , Triazóis/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Clivagem do DNA/efeitos da radiação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Moluscos/enzimologia , Staphylococcus aureus/efeitos dos fármacos
17.
3 Biotech ; 7(1): 42, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28444586

RESUMO

Phytic acid is a main reservoir of phosphorous (P) in plants and contributes to about 80% of the total P in cereal seeds. However, it is well known to possess anti-nutritional behavior. Because it has strong affinity to chelate divalent ions e.g. calcium, magnesium, and especially with iron and zinc. Therefore, it is extremely poor as a dietary source of P. To enhance bio-availability of micronutrients, an enzyme namely phytase is known to hydrolyze phytic acid. Unfortunately, phytase is not produced in the stomach of monogastric animals and humans. Thus, the presence of phytic acid in cereal foods has become major concern about the deficiency of essential micronutrients in developing countries. To address this problem, various types of phytase have been isolated, purified and characterized from different varieties of cereal till date. Therefore, the present article discusses about catalytic properties, gene regulation of such cereal phytases and their importance in ensuring food safety.

18.
Indian J Med Res ; 144(2): 264-270, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27934807

RESUMO

BACKGROUND & OBJECTIVES: Dental caries is an infectious, transmissible disease. Maternal transfer of mutans streptococci (MS) has been a subject of research. The aim of this study was to evaluate the transmission of MS from mother to children through genetic analysis. METHODS: Thirty mother-child pairs were included and divided into three groups according to the age of the children. Saliva samples were collected and MS colonies from each mother-child pair were isolated. After inoculation and incubation, MS colonies were submitted to amplification technique by polymerase chain reaction (PCR) for identification and arbitrarily primed PCRs (AP-PCRs) to determine various MS genotypes. RESULTS: From birth to six months of age, 30 per cent of children exhibited MS colonization, and by the age of 30 months, 100 per cent harboured the bacteria (P < 0.001). Factors associated with MS colonization were eruption of teeth (P < 0.001), feeding habits with mean colony count being significantly lower in breast-fed as compared to bottle-fed children (P < 0.001) and a significant association between mean MS count of child and mother's practice of sharing spoon with child (P < 0.001). The AP-PCR fingerprinting profile analysis showed 17 MS groups (clusters) containing identical or highly related isolates in mother-child pairs with a high level of similarity (77.27 %). INTERPRETATION & CONCLUSIONS: The presence of matching MS genotypes suggested vertical transmission from mothers to children. Feeding habits, gum cleaning and number of erupted teeth in children had significant effect on MS colonization. There is a need to develop strategies to present MS colonization in children.


Assuntos
DNA Bacteriano/isolamento & purificação , Cárie Dentária/microbiologia , Transmissão Vertical de Doenças Infecciosas , Streptococcus mutans/isolamento & purificação , Adulto , DNA Bacteriano/genética , Cárie Dentária/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Relações Mãe-Filho , Saliva/microbiologia , Streptococcus mutans/genética
19.
AMB Express ; 6(1): 46, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27411334

RESUMO

Tannase (tannin acyl hydrolase E.C 3.1.1.20) is an inducible, largely extracellular enzyme that causes the hydrolysis of ester and depside bonds present in various substrates. Large scale industrial application of this enzyme is very limited owing to its high production costs. In the present study, cost effective production of tannase by Klebsiella pneumoniae KP715242 was studied under submerged fermentation using different tannin rich agro-residues like Indian gooseberry leaves (Phyllanthus emblica), Black plum leaves (Syzygium cumini), Eucalyptus leaves (Eucalyptus glogus) and Babul leaves (Acacia nilotica). Among all agro-residues, Indian gooseberry leaves were found to be the best substrate for tannase production under submerged fermentation. Sequential optimization approach using Taguchi orthogonal array screening and response surface methodology was adopted to optimize the fermentation variables in order to enhance the enzyme production. Eleven medium components were screened primarily by Taguchi orthogonal array design to identify the most contributing factors towards the enzyme production. The four most significant contributing variables affecting tannase production were found to be pH (23.62 %), tannin extract (20.70 %), temperature (20.33 %) and incubation time (14.99 %). These factors were further optimized with central composite design using response surface methodology. Maximum tannase production was observed at 5.52 pH, 39.72 °C temperature, 91.82 h of incubation time and 2.17 % tannin content. The enzyme activity was enhanced by 1.26 fold under these optimized conditions. The present study emphasizes the use of agro-residues as a potential substrate with an aim to lower down the input costs for tannase production so that the enzyme could be used proficiently for commercial purposes.

20.
Dent Res J (Isfahan) ; 13(6): 552-559, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28182053

RESUMO

BACKGROUND: The aim of this study was to assess the relationships of quantitative salivary levels of mutans streptococci (MS) in children, aged 3-6 years and 12-15 years, exhibiting variable patterns of caries activity, and to compare the association of MS in saliva using microbial and molecular (polymerase chain reaction [PCR]) assay. MATERIALS AND METHODS: In this cross-sectional observational study, eighty children were included, forty children each in Group I (3-6 years) and Group II (12-15 years). Children were further divided into two subgroups (Group IC, INC and Group IIC, IINC) based on their dental caries status. Saliva samples were collected and plated onto Mitis Salivarius-Bacitracin agar plates. After detection of MS, DNA was isolated and purified, and MS were evaluated using the PCR and AP-PCR. RESULTS: Of the selected 80 children, 42 were male and 38 were female. In Group IC, the mean colony count was 2.27 ± 0.54 × 105 CFU/ml, and in Group INC, the mean colony was found to be 1.61 ± 0.54 × 105 CFU/ml. In Group II, where mean colony count of 3.31 ± 0.85 × 105 CFU/ml and 2.44 ± 0.54 × 105 CFU/ml was observed in Group IIC and Group IINC, respectively. CONCLUSION: The mean colony count increased with increasing age and was also more in children with dental caries. Based on the matrices generated by the PCR analysis using coefficient slipped-strand mispairing, wide range of genetic diversity was seen in cases of children with and without clinically detectable caries.

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