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1.
J Conserv Dent ; 26(2): 150-159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37205881

RESUMO

Objective: The objective of this study was to study the effect of medicated toothpaste on oral health, a 6-month follow-up. Methods: Four hundred and twenty-seven participants were screened and followed up for 6 months. The intraoral examination was performed to record caries, gingival bleeding, and plaque index. Saliva collected was evaluated for pH, total antioxidant capacity (TAC), malondialdehyde (MDA), and Vitamin C level for 6 months, and data were analyzed. Results: On the usage of medicated toothpaste with herbal extract for 6 months, the salivary pH levels were increased, the interquartile range for plaque, and the gingival bleeding index decreased. The percentage change in salivary TAC, MDA, and Vitamin C levels in the caries-free group of subgroup I was 174.8, 58.06, and 59.98, respectively, in subgroup II was 133.3, 52.08, and 58.51, and in subgroup III was 63.77, 45.11, and 47.77. The percentage change in salivary TAC, MDA, and Vitamin C levels in the caries-active group of subgroup I was 136.62, 57.27, and 72.83, subgroup II was 108.59, 37.50, and 61.55, and in subgroup III was 35.62, 30.82, and 54.10, respectively. Conclusion: The salivary pH levels increased on the usage of medicated toothpaste with herbal extract; plaque and the gingival bleeding index scores were decreased. The salivary antioxidant defense was increased in individuals using medicated toothpaste with herbal extracts which signifies an improvement in overall oral health in the 6-month follow-up.

2.
J Fungi (Basel) ; 8(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35628709

RESUMO

The soil microbiome contributes to nutrient acquisition and plant adaptation to numerous biotic and abiotic stresses. Numerous studies have been conducted over the past decade showing that plants take up nutrients better when associated with fungi and additional beneficial bacteria that promote plant growth, but the mechanisms by which the plant host benefits from this tripartite association are not yet fully understood. In this article, we report on a synergistic interaction between rice (Oryza sativa), Piriformospora indica (an endophytic fungus colonizing the rice roots), and Azotobacter chroococcum strain W5, a free-living nitrogen-fixing bacterium. On the basis of mRNA expression analysis and enzymatic activity, we found that co-inoculation of plant roots with the fungus and the rhizobacterium leads to enhanced plant growth and improved nutrient uptake compared to inoculation with either of the two microbes individually. Proteome analysis of O. sativa further revealed that proteins involved in nitrogen and phosphorus metabolism are upregulated and improve nitrogen and phosphate uptake. Our results also show that A. chroococcum supports colonization of rice roots by P. indica, and consequentially, the plants are more resistant to biotic stress upon co-colonization. Our research provides detailed insights into the mechanisms by which microbial partners synergistically promote each other in the interaction while being associated with the host plant.

3.
Biotechnol Biofuels ; 12: 176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316583

RESUMO

BACKGROUND: Many studies have been carried out on the growth-modulating efficiency of plants by the colonization of an endophytic fungus Piriformospora indica. However, studies involving the co-culture of alga with endophytic fungal strains for enhanced biodiesel production are rare. In this study, the interaction between P. indica and Parachlorella kessleri-I, a marine algal strain, was assessed at metabolic level. RESULTS: In association with an endophytic fungus, the algal biomass enhanced from 471.6 to 704 mg/L, and the fatty acid methyl ester (FAME) profile of P. kessleri-I increased substantially. In case of FAME profile of co-cultured P. kessleri-I, two essential components of biodiesel, i.e. elaidic acid and oleic acid, increased by 1.4- and 1.8-fold, respectively. To ascertain changes in the metabolic profile of P. kessleri-I by P. indica co-culture, gas chromatography-mass spectrometry (GC-MS)-based untargeted metabolomics study was performed to identify the metabolites involved; and differential nature of the essential metabolites was also confirmed using HPLC and LC-MS. Significant modulation of the bioactive metabolites such as succinate, oxo-propanoate, l-alanine, glutamate, acetate and 1,2 propanediol, hydroxy butane was observed. CONCLUSION: The metabolites like glutamate and succinate that usually belong to the GABA shunt pathway were observed to be upregulated. The pathway links nitrogen metabolism and carbon metabolism, thus influencing the growth and lipid profile of the algae. These differential metabolites thus indicated the important commensal association between the endophytic fungus and autotrophic marine alga, and established that endophytic fungus can be handy for the sustainability of algal biofuel industries.

4.
Protoplasma ; 254(2): 617-626, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27468993

RESUMO

The growing human population and depletion of resources have necessitated development of sustainable agriculture. Beneficial plant-microbe associations have been known for quite some time now. To maintain sustainability, one could show better reliance upon beneficial attributes of the rhizosphere microbiome. To harness the best agronomic traits, understanding the entire process of recruitment, establishment, and maintenance of microbiota as stable interactome within the rhizosphere is important. In this article, we highlight the process of recruitment and establishment of microbiota within rhizosphere. Further, we have discussed the interlinkages and the ability of multiple (microbial and plant) partners to interact with one another forming a stable plant holobiont system. Lastly, we address the possibility of exploring the knowledge gained from the holobiont system to tailor the rhizosphere microbiome for better productivity and maintenance of agroecosystems. The article provide new insights into the broad principles of stable plant-microbe interactions which could be useful for sustaining agriculture and food security.


Assuntos
Interações Microbianas , Microbiota , Plantas/microbiologia , Rizosfera , Ecossistema , Modelos Biológicos
5.
Sci Rep ; 5: 13911, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26350628

RESUMO

Microbial communities in rhizosphere interact with each other and form a basis of a cumulative impact on plant growth. Rhizospheric microorganisms like Piriformospora indica and Azotobacter chroococcum are well known for their beneficial interaction with plants. These features make P. indica/A. chroococcum co-inoculation of crops most promising with respect to sustainable agriculture and to understanding the transitions in the evolution of rhizospheric microbiome. Here, we investigated interactions of P. indica with A. chroococcum in culture. Out of five Azotobacter strains tested, WR5 exhibited growth-promoting while strain M4 exerted growth-inhibitory effect on the fungus in axenic culture. Electron microscopy of co-culture indicated an intimate association of the bacterium with the fungus. 2-D gel electrophoresis followed by mass spectrometry of P. indica cellular proteins grown with or without WR5 and M4 showed differential expression of many metabolic proteins like enolase-I, ureaseD, the GTP binding protein YPT1 and the transmembrane protein RTM1. Fungal growth as influenced by bacterial crude metabolites was also monitored. Taken together, the results conform to a model where WR5 and M4 influence the overall growth and physiology of P. indica which may have a bearing on its symbiotic relationship with plants.


Assuntos
Azotobacter/fisiologia , Basidiomycota/fisiologia , Interações Microbianas , Azotobacter/ultraestrutura , Basidiomycota/ultraestrutura , Proteínas Fúngicas/metabolismo , Proteoma , Proteômica/métodos , Metabolismo Secundário
6.
J Org Chem ; 78(6): 2373-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23394110

RESUMO

We report a special, hitherto-unexplored property of (-)-epigallocatechin gallate (EGCG) as a chiral solvating agent for enantiodiscrimination of α-amino acids in the polar solvent DMSO. This phenomenon has been investigated by (1)H NMR spectroscopy. The mechanism of the interaction property of EGCG with α-amino acids has been understood as arising out of hydrogen-bonded noncovalent interactions, where the -OH groups of two phenyl rings of EGCG play dominant roles. The conversion of the enantiomeric mixture into diastereomers yielded well-resolved peaks for D and L amino acids permitting the precise measurement of enantiomeric composition. Often one encounters complex situations when the spectra are severely overlapped or partially resolved hampering the testing of enantiopurity and the precise measurement of enantiomeric excess (ee). Though higher concentration of EGCG yielded better discrimination, the use of lower concentration being economical, we have exploited an appropriate 2D NMR experiment in overcoming such problems. Thus, in the present study we have successfully demonstrated the utility of the bioflavonoid (-)-EGCG, a natural product as a chiral solvating agent for the discrimination of large number of α-amino acids in a polar solvent DMSO. Another significant advantage of this new chiral sensing agent is that it is a natural product and does not require tedious multistep synthesis unlike many other chiral auxiliaries.


Assuntos
Aminoácidos/química , Catequina/análogos & derivados , Flavonoides/química , Solventes/química , Chá/química , Catequina/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Estereoisomerismo
7.
Food Funct ; 3(6): 592-605, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22465955

RESUMO

Tea and coffee are widely consumed beverages across the world and they are rich sources of various polyphenols. Polyphenols are responsible for the bitterness and astringency of beverages and are also well known to impart antioxidant properties which is beneficial against several oxidative stress related diseases like cancer, cardiovascular diseases, and aging. On the other hand, proteins are also known to display many important roles in several physiological activities. Polyphenols can interact with proteins through hydrophobic or hydrophilic interactions, leading to the formation of soluble or insoluble complexes. According to recent studies, this complex formation can affect the bioavailability and beneficiary properties of both the individual components, in either way. For example, polyphenol-protein complex formation can reduce or enhance the antioxidant activity of polyphenols; similarly it can also affect the digestion ability of several digestive enzymes present in our body. Surprisingly, no review article has been published recently which has focused on the progress in this area, despite numerous articles having appeared in this field. This review summarizes the recent trends and patterns (2005 onwards) in polyphenol-protein interaction studies focusing on the characterization of the complex, the effect of this complex formation on tea and coffee taste, antioxidant properties and the digestive system.


Assuntos
Antioxidantes/metabolismo , Café/metabolismo , Sistema Digestório/metabolismo , Polifenóis/metabolismo , Proteínas/metabolismo , Chá/metabolismo , Animais , Antioxidantes/química , Café/química , Sistema Digestório/química , Humanos , Polifenóis/química , Ligação Proteica , Proteínas/genética , Paladar , Chá/química
8.
J Phys Chem B ; 115(41): 11823-30, 2011 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-21905674

RESUMO

Photophysical properties of cationic Acridine Orange (AO) have been studied in different micellar environments [anionic SDS (sodium dodecyl sulfate), nonionic TX (TritonX-100), and cationic CTAB (cetyl trimethyl ammonium bromide)] at different pH, in the presence of a metal ion (Cu(2+)). At pH ∼ 8, addition of Cu(2+) results in AO fluorescence quenching in the presence of SDS micelle, enhancement of the same in the presence of TX micelle, and remaining unaltered in the presence of CTAB micelle. At pH ∼ 2, addition of Cu(2+) results in AO fluorescence quenching only in the presence of SDS micelle, and it remains mostly unaffected in the presence of TX and CTAB. Availability of Cu(2+) toward AO and binding of Cu(2+) with AO at the charged micellar interface are responsible for this pH-dependent Cu(2+)-mediated micellar charge selective fluorescence pattern.


Assuntos
Laranja de Acridina/química , Cobre/química , Corantes Fluorescentes/química , Micelas , Concentração de Íons de Hidrogênio , Íons/química , Octoxinol/química , Compostos de Amônio Quaternário/química , Dodecilsulfato de Sódio/química
9.
Chem Commun (Camb) ; 47(31): 8937-9, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21743894

RESUMO

Polysaccharide-induced protein fluorescence 'turn-on' responses have been studied in the presence of similarly charged micelle at pH ∼3. Quenched protein fluorescence is selectively recovered ('on' state) for bovine serum albumin (BSA) with sodium carboxy methyl cellulose (SCMC) and for pepsin (PS) with chitosan (CS) with starting ultra low concentrations of 0.04 µM and 0.008 µM respectively.


Assuntos
Biopolímeros/química , Animais , Carboximetilcelulose Sódica/química , Bovinos , Quitosana/química , Concentração de Íons de Hidrogênio , Micelas , Pepsina A/química , Soroalbumina Bovina/química
10.
J Phys Chem B ; 114(35): 11462-7, 2010 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-20715876

RESUMO

The fluorescence response of pyrene has been studied in the presence of nonionic brij micelles and poly(acrylic acid) (PAA) with benzophenone (BP) as a neutral hydrophobic quencher. Pyrene emission is quenched ("off" state) in the presence of BP in brij 35 (polyoxyethylene-23-lauryl ether) and brij 56 (polyoxyethylene-10-cetyl ether) micelles. Quenched pyrene emission is selectively recovered ("on" state) for brij 35 micelles with the addition of PAA (starting conc 2.0 x 10(-5) M). Due to the interaction of PAA and brij 35 micelles and the relatively easier accessibility of PAA polymer chains near the bulky polyoxyethylene chain of brij 35 micelles, the chances of BP partition inside the hydrophobic polymer coil are more compared to brij 56 micelles. The PAA sensing ability of the "brij 35:pyrene:BP" system is dependent on the molecular weight (M) of the polymer. Fluorescence recovery has been observed with PAA (M approximately 150000) and complete recovery has been recorded with high M of PAA (M approximately 450000); however, no fluorescence change is observed in the presence of low M of PAA (M approximately 2000). In solution, such selective reversible fluorescence quenching has the potential for a new class of highly sensitive chemical sensor systems.


Assuntos
Resinas Acrílicas/química , Benzofenonas/química , Micelas , Cetomacrogol/química , Interações Hidrofóbicas e Hidrofílicas , Nefelometria e Turbidimetria , Polietilenoglicóis/química , Pirenos/química
11.
Anal Biochem ; 397(1): 89-95, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19818329

RESUMO

In this article, we report tuning of the sensory capability of an amino acid (tryptophan) in a biomimicking anionic micellar nano cage. It has been shown that anionic surfactant concentration dictates the sensing behavior of tryptophan toward body malodor component (butyric acid) generated by bacterial degradation of tributyrin. We have proposed a fluorescence quenching mechanism that is based on short-chain fatty acid (SCFA) proximity with tryptophan present at the micelle-water interface. Anionic surfactant-induced fluorescent sensor activity of tryptophan exhibits high sensitivity (detection limit up to 10 microM) and specific selectivity (toward SCFA, < C12) in aqueous solution. We also determined antibacterial efficacy of various zinc salts based on the sensory activity of tryptophan, which has been correlated with the established resazurin assay.


Assuntos
Ânions/química , Espectrometria de Fluorescência/métodos , Tensoativos/química , Triptofano/análise , Axila/microbiologia , Bactérias/isolamento & purificação , Ácido Butírico/metabolismo , Fluorescência , Humanos , Micelas , Oxazinas/metabolismo , Triptofano/química , Xantenos/metabolismo , Zinco/química
12.
J Phys Chem B ; 113(41): 13462-4, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19764733

RESUMO

We report herein the fluorescence response of pyrene in the presence of sodium dodecyl sulfate (SDS) micelle and poly(acrylic acid) (PAA) with Cu(2+) as an ionic quencher. Pyrene present in the PAA-SDS complex is quenched by Cu(2+) at pH approximately 2 ("off" state). Quenched pyrene emission is recovered at pH approximately 8 ("on" state). Due to easy protonation and deprotonation of the PAA chain in aqueous solution, this pH-controlled micellar ternary system exhibits a highly reversible "off-on-off" switch of the pyrene emission.


Assuntos
Resinas Acrílicas/química , Cobre/química , Corantes Fluorescentes/química , Micelas , Pirenos/química , Dodecilsulfato de Sódio/química , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência
13.
Colloids Surf B Biointerfaces ; 58(2): 305-8, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17412571

RESUMO

A study of the self-organization of nonionic surfactant span 60 (sorbitan mono stearate) in presence of fatty alcohol (stearyl, cetyl and lauryl) is presented. When ethanolic solution of the surfactant-fatty alcohol (1:1) mixture is added in water spontaneous large unilamellar vesicles (LUV) are formed which may potentially be useful vehicles for drug delivery purposes. Vesicular suspension has been characterized by transmission electron microscopy, dynamic light scattering, confocal laser scanning microscopy, dye entrapment and release studies. Surface tension measurement indicates the suitability of fatty alcohols towards spontaneous vesicle formation from span 60.


Assuntos
Sistemas de Liberação de Medicamentos , Etanol , Álcoois Graxos , Hexoses , Lipossomos , Água
14.
Colloids Surf B Biointerfaces ; 58(1): 68-71, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17339104

RESUMO

Niosomal hybrid mixtures are prepared with bilayer stabilizer cholesterol from non-ionic surfactants span 20 (HLB value 8.6), span 60 (HLB 4.7) and span 85 (HLB 1.8) in presence of dicetyl phosphate (DCP) where fatty acids or fatty alcohols (C14, C16 and C18) are used as carrier. Hybrid mixtures upon hydration with aqueous phosphate buffer (pH 7.4) spontaneously produce vesicular phase which can encapsulate 5(6)-carboxyfluorescein (CF). Effect of fatty alcohols and fatty acids on the vesicle size has been studied by dynamic light scattering (DLS), freeze-fracture scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Release rates of CF from vesicular suspensions are found to be dependent on carriers as well as surfactants used. Fatty acid coated hybrids form large multilamellar vesicles (LMV) (size range 10-15 microm) where as fatty alcohol coated hybrid systems form small multilamellar vesicles (SMV) with an average diameter of 400 nm, in all cases vesicles are polydisperse (PI approximately 0.9) in nature.


Assuntos
Portadores de Fármacos , Ácidos Graxos/química , Álcoois Graxos/química , Fluoresceínas/química , Corantes Fluorescentes/química , Lipossomos/química , Técnica de Fratura por Congelamento , Hexoses/química , Bicamadas Lipídicas/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
15.
Colloids Surf B Biointerfaces ; 58(1): 14-9, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17284355

RESUMO

A cryptand with six secondary amino groups has been derivatized by reacting with acid chlorides of different chain lengths (C(7), C(10) and C(18)) to get three cryptand based hexa-tailed neutral amphiphiles (L(1)-L(3)). The cavity of the cryptand head group accommodates two Cu(II) ion giving another set of three amphiphiles. These amphiphiles and its copper complexes can aggregate spontaneously as giant vesicular microcapsules in 10% ethanolic water medium. In all cases vesicles formed are mostly unilamellar in nature. Vesicular microcapsules prepared from L(1)-L(3) can encapsulate hydrophilic dye 5(6)-carboxyfluorescein (CF). Stability of microcapsules, CF encapsulation efficiencies and release rates were dependent on the hydrophobic chain length of the amphiphiles. Results show the permeability of the L(2) and L(3) bilayer is lower than that of phosphatidylcholine vesicles and the loading capacity is approximately 3 times greater. Microcapsules have been characterized by optical microscopy, freeze fracture scanning electron microscopy and confocal fluorescence microscopy.


Assuntos
Cápsulas/síntese química , Tensoativos/química , Coloides/química , Éteres de Coroa/síntese química , Técnica de Fratura por Congelamento , Microscopia Confocal
16.
Bioconjug Chem ; 13(6): 1314-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12440868

RESUMO

A family of conjugates has been synthesized from spermine, putrescine, lysine, gamma-aminobutyric acid, sarcosine, cholic acid, glycocholic acid, 3alpha,7alpha-dihydroxycholic acid, and 3alpha,12alpha-dihydroxycholic acid, based on a design principle previously reported (Bandyopadhyay, P., Janout, V., Zhang, L., Regen, S. L. (2001) J. Am. Chem. Soc. 123, 7691). Each of these conjugates was found to exhibit significant activity in promoting the transport of Na(+) across liposomal membranes derived from 1,2-dimyristoleoyl-sn-glycero-3-phosphocholine, and also from 1,2-dipalmitoleoyl-sn-glycero-3-phosphocholine. In all cases, plots of pseudo first-order rate constants, k(obsd) vs (mol % of ion conductor)(2) were found to be linear, indicating that transport-active dimers are involved and that only a small fraction of the conjugates are in an aggregated form. An operational comparison that has been made within this series of conjugates indicates that Na(+) transport activity and membrane selectivity have a moderate dependency on the composition and the structure of the ion conductor.


Assuntos
Aminoácidos/química , Ácidos e Sais Biliares/química , Aminas Biogênicas/química , Íons/química , Desenho de Fármacos , Estrutura Molecular
17.
J Am Chem Soc ; 124(38): 11254-5, 2002 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-12236724

RESUMO

A synthetic ion conductor (1), derived from cholic acid and spermine, has been found capable of recognizing osmotic stress in liposomes made from 1,2-dipalmitoleoyl-sn-glycero-3-phosphocholine [(C16:1)PC]. Thus, when large unilamellar vesicles of (C16:1)PC are placed under hypotonic conditions, the Na+/Li+ transport activity of 1 increases by as much as 1 order of magnitude, relative to isotonic conditions


Assuntos
Antiporters/química , Bicamadas Lipídicas/química , Fosfolipídeos/química , Antiporters/metabolismo , Lipossomos/química , Concentração Osmolar , Fosforilcolina/química
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