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1.
Environ Res ; 212(Pt A): 113136, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35351453

RESUMO

WO3/Zeolite/V2O5 (TZV) composite synthesized through co-precipitation was used for the degradation of Bisphenol-A (BpA). XRD and Raman spectra were employed to ascertain the crystallinity of the composite. The pristine nature of the compound without any free particles over the zeolite surface was established through FESEM, thus, substantiating the composite character of the material. The enhancement in activity after doping with WO3 was ascertained by DRS-UV. Photocatalytic degradation studies clearly established the superiority of TZV 10 over bare V2O5. Complete BpA degradation (100%) was attained at 50 min of incubation with 0.75 g/L TZV-10 in acidic medium (pH 3) for an initial BpA concentration of 100 mg/L. HPLC-MS/MS analysis was used to decipher the degradation pathway. The catalyst was stable even after 9 cycles. Phytotoxicity studies and lake water treatment results proved the environmental efficiency of the synthesized material.


Assuntos
Zeolitas , Compostos Benzidrílicos/toxicidade , Catálise , Fenóis/química , Espectrometria de Massas em Tandem
2.
Bioprocess Biosyst Eng ; 43(5): 821-830, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31919603

RESUMO

Bacillus bacteria have major utility in large-scale production of industrial enzymes, among which proteases have particular importance. B. subtilis B22, an aerobic and chemotrophic strain, was isolated from kimchi and identified by 16S rRNA gene sequencing. Extracellular protease production was determined in basic medium, with 1% (w/v) casein as substrate, by submerged fermentation at 37 °C under blue, green, red and white light-emitting diodes (LEDs), white fluorescent light and darkness. Fermentation under blue LEDs maximized protease production (110.79 ± 1.8 U/mL at 24 h). Various agricultural waste products enhanced production and groundnut oil cake yielded the most protease (334 ± 1.8 U/mL at 72 h). Activity and stability of the purified protease were optimum at pH 7-10 and 20-60 °C. Activity increased in the presence of Ca2+, Mg2+ and Mn2+, while Fe2+, Zn2+, Co2+ and Cu2+ moderated activity, and Ni2+ and Hg2+ inhibited activity. Activity was high (98%) in the presence of ethylenediaminetetraacetic acid (EDTA) but inhibited by phenylmethanesulfonyl fluoride (PMSF). The protease was unaffected by nonionic surfactants, tolerated an anionic surfactant and oxidizing agents, and was compatible with multiple organic solvents. These properties suggest utility of protease produced by B. subtilis B22 under blue LEDs for industrial applications.


Assuntos
Agricultura , Bacillus subtilis/crescimento & desenvolvimento , Proteínas de Bactérias/biossíntese , Luz , Peptídeo Hidrolases/biossíntese , Gerenciamento de Resíduos
3.
Bioprocess Biosyst Eng ; 42(4): 529-539, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30542760

RESUMO

Light and bacteria can be used in combination to enhance secondary metabolite production during fermentation. Red yeast rice powder (RYRP) was inoculated with Bacillus subtilis (B2) isolated from freshwater seafood and incubated under light-emitting diodes (LEDs) of different colors (blue, green, red, white), fluorescent white light, and in darkness. Blue LED-mediated fermentation with B2 significantly enhanced production of phenolic compounds (68.4 ± 1 mg GAE/g DW) and flavonoids (51.7 ± 1 mg QE/g DW) compared to white light and darkness. Total antioxidant activity of RYRP extract after fermentation with B2 was > 77%; hydroxyl radical and superoxide scavenging were > 66%. DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging activities were 51% and > 67%, respectively. Reducing power was approximately twice that of extract from RYRP without B2. FTIR analysis showed a high content of hydroxyl, nitrile and carboxylic groups in the extract. Derivatives of cinnamic, benzoic and phophinodithioic acid, and quinazolinone were identified by GC-MS. Findings show that fermenting RYRP with B. subtilis B2 under blue LEDs enhances production of secondary metabolites, which should have applications in industrial fermentation processes.


Assuntos
Antioxidantes/metabolismo , Bacillus subtilis/crescimento & desenvolvimento , Produtos Biológicos/química , Luz
4.
Prep Biochem Biotechnol ; 49(2): 143-150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30636516

RESUMO

A chemotrophic, aerobic bacterial strain, Bacillus subtilis B2, was used to produce amylase by submerged fermentation under different light sources. SDS-PAGE indicated that the 55 kDa enzyme belonged to the α-amylase group. B2 was incubated in basal media with 1% soluble starch (pH 7.0) under blue, green, red, and white light-emitting diodes (LEDs), and white fluorescent light. Fermentation under blue LEDs maximized amylase production (180.59 ± 1.6 U/mL at 24 h). Production at 48 h increased to 310.56 ± 1.6 U/mL with 5% glucose as a simple carbon source and to 300.51 ± 1.7 U/mL with 5% groundnut oil cake as an agricultural waste substrate. Activity and stability of the amylase were greatest at pH 7.0 and 45-55 °C. Na+, Ca2+, Mg2+, Co2+, Ba2+, and K+ increased activity, while Ni2+, Hg2+, Mn2+, Cu2+, Fe3+, and Zn2+ inhibited activity. EDTA, PMSF and DTNB reduced activity by 50% or more, while tetrafluoroethylene and 1,10-phenanthroline reduced activity by 30%. The amylase was highly tolerant of the surfactants, compatible with organic solvents, oxidizing agents and the reducing agents reduced activity. These properties suggest utility of amylase produced by B. subtilis B2 under blue LED-mediated fermentation for industrial applications.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Microbiologia Industrial/métodos , alfa-Amilases/metabolismo , Bacillus subtilis/química , Bacillus subtilis/efeitos da radiação , Proteínas de Bactérias/química , Cátions Bivalentes/metabolismo , Estabilidade Enzimática , Fermentação , Concentração de Íons de Hidrogênio , Luz , Metais/metabolismo , Temperatura , alfa-Amilases/química
5.
3 Biotech ; 11(6): 268, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34017674

RESUMO

Berries are rich in bioactive phytochemicals and phenolic compounds. In the present study, strawberry leaves obtained from Nangsan-myeon, Jeollabuk-do, Korea in 2019 were fermented using Lactiplantibacillus plantarum B1-4 and studied for antioxidant and anti-inflammatory properties. Comparative testing of active ingredients in the raw and fermented extract showed an increase in total polyphenol content and total flavonoid content from 92.0 mg GAE/g and 40.4 mg QE/g, respectively, to 116.1 mg GAE/g and 49.5 mg QE/g, respectively, in fermented extracts. Similarly, catechin content in fermented extract was increased by 26.5% and epicatechin content was decreased by 9.3%. Total and reducing sugar contents in the fermented extract were decreased by 58.4% and 50.4%. DPPH radical scavenging activity of the extracts before and after fermentation increased by about 10.7% from 35.6 to 46.3% at 250 µg/mL and ABTS by about 6.0% from 48.6 to 54.6% at 500 µg/mL. Cytotoxicity assay confirmed that fermented extract caused no harm to chromatid structure of RAW 264.7 cells up to 500 µg/mL concentration. Fermented extracts (400 µg/mL) reduced nitric oxide production (9.7%) and the levels of TNF-α (18.1%) and IL-6 (11.8%), making them ideal for integration into skin care products. The significant functional groups present in raw and fermented extracts were identified using FTIR. Thus, this study adds to the notion of using fermented extracts in functional foods due to their anti-inflammatory properties.

6.
Immunopharmacol Immunotoxicol ; 32(4): 607-10, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20175642

RESUMO

The methanolic extract of the leaves of Chinese Hawthorn was investigated for its activity against chloroquine-sensitive strains of Plasmodium falciparum using the method of parasite lactate dehydrogenase assay. Four oligomeric procyanidins, such as epicatechin-(4ß→8)-epicatechin-(4ß→8)-epicatechin (1), epicatechin-(4ß→8)-epicatechin-(4ß→6)-epicatechin (2), epicatechin-(4ß→6)-epicatechin-(4ß→8)-epicatechin (3), and epicatechin-(4ß→8)-epicatechin-(4ß→8)-epicatechin-(4ß→8)-epicatechin-(4ß→8) (4), were isolated and evaluated for in vitro antiplasmodial activity, as well as for their cytotoxic potential on SK-OV-3 cancer cell lines. Three procyanidins showed notable growth inhibitory activity against chloroquine-sensitive strains of P. falciparum with IC(50) values of 2.7 µM (SI values of >55.5). The compounds showed no significant cytotoxicity (IC(50) > 150 µM) toward the SK-OV-3 cancer cell line. This is the first report on the antiplasmodial activity of these oligomeric procyanidins from Chinese Hawthorn.


Assuntos
Antimaláricos/farmacologia , Crataegus/química , Medicamentos de Ervas Chinesas/química , Folhas de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Proantocianidinas/isolamento & purificação , Proantocianidinas/farmacologia , Antimaláricos/química , Antimaláricos/isolamento & purificação , Catequina/análogos & derivados , Catequina/química , Catequina/isolamento & purificação , Catequina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Humanos , Concentração Inibidora 50 , Metanol/química , Estrutura Molecular , Proantocianidinas/química
7.
Immunopharmacol Immunotoxicol ; 32(4): 611-3, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20163192

RESUMO

The rhizomes parts of Angelica purpuraefolia were extracted and the major essential oils composition and immunotoxic effects were studied. The analyses were conducted by gas chromatography and mass spectroscopy (GC-MS) revealed that the essential oils of A. purpuraefolia. The A. purpuraefolia essential oil (APEO) yield was 0.37%, and GC/MS analysis revealed that its major constituents were ß-Phellandrene (32.11%), Nerolidol (10.11%), Pyrimidine derivative (27.33%), Heptadecane (4.33%), and Celorbicol (6.33%). The essential oil had a significant toxic effect against early fourth-stage larvae of Aedes aegypti L with an LC(50) value of 31.21 ppm and an LC(90) value of 87.22 ppm. The results could be useful in search for newer, safer, and more effective natural immunotoxic agents against A. aegypti.


Assuntos
Aedes/efeitos dos fármacos , Angelica/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Alcanos/análise , Animais , Monoterpenos Cicloexânicos , Cicloexenos/análise , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Dose Letal Mediana , Monoterpenos/análise , Óleos Voláteis/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Pirimidinas/análise , Rizoma/química , Sesquiterpenos/análise
8.
J Basic Microbiol ; 50(2): 200-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20082369

RESUMO

The enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase cleaves the ethylene precursor ACC into alpha-ketobutyrate and ammonia. The decreased level of ethylene allows the plant to be more resistant to a wide environmental stress including plant pathogens. In the present study, we characterized the ACC deaminase activity of a Pseudomonas entomophila strain PS-PJH isolated from the red pepper rhizosphere region of red pepper grown at Jinan, Korea. The isolate produced 23.8 +/- 0.4 micromol of alpha-ketobutyrate/mg of protein/h during ACC deamination under in vitro conditions. Polymerase chain reaction for acdS gene showed that the isolated P. entomophila strain PS-PJH carry sequences similar to the known acdS genes. Results of the multiple sequence alignment revealed >99% identity (nucleotide and amino acid) with acdS gene of Pseudomonas putida strains AM15 and UW4. The isolated bacteria promoted 43.3 and 34.1% of growth in Raphanus sativus and Lactuca sativa plants, respectively. Based on the 16S-23S internal transcribed spacer region sequences, the isolate was identified as P. entomophila. To the best of our knowledge this is the first study to report the acdS gene in P. entomophila.


Assuntos
Carbono-Carbono Liases/genética , Carbono-Carbono Liases/metabolismo , Pseudomonas/enzimologia , Pseudomonas/isolamento & purificação , Microbiologia do Solo , Amônia/metabolismo , Butiratos/metabolismo , Capsicum/microbiologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Coreia (Geográfico) , Dados de Sequência Molecular , Filogenia , Raízes de Plantas/microbiologia , Reação em Cadeia da Polimerase , Pseudomonas/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
9.
Environ Sci Pollut Res Int ; 27(1): 837-845, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31813123

RESUMO

Soil contamination with benzene, toluene, ethylbenzene and xylene isomers (BTEX) has raised increasing concern because of its high solubility in water and toxicity to biotic communities. This study aims at investigating the process and prospects of deploying bioelectrochemical system (BES) for the removal of BTEX from artificially contaminated soil using Pseudomonas putida YNS1, alongside the reduction of hexavalent chromium (Cr(VI)). The BES was setup with desired operating conditions: initial concentration of BTEX (50-400 mg/L in 100 mL of sterilized water), pH (4-10) and applied potential voltage (0.6-1.2 V) with 10 µL log-phase culture along with the addition of Cr(VI) (10 mg/L). Samples were collected at regular intervals and analysed for BTEX degradation using gas chromatography and Cr(VI) reduction using UV-Vis spectrophotometer. Under optimized conditions (initial BTEX concentration, 200 mg/L; pH 7; and applied voltage 0.8 V with Cr(VI) of 10 mg/L), 92% of BTEX was degraded and 90% Cr(VI) was reduced from the contaminated soil. The intermediates produced during degradation were analysed through gas chromatography-flame ionization detector (GC-FID), and the possible degradation pathway was elucidated. The results indicated that BES could be effective for simultaneous degradation of BTEX along with Cr(VI) reduction.


Assuntos
Cromo/química , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Benzeno/análise , Derivados de Benzeno/análise , Cromatografia Gasosa , Isomerismo , Pseudomonas putida/metabolismo , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Tolueno/análise , Xilenos/análise
10.
Chemosphere ; 249: 126083, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32045753

RESUMO

Exposure to endocrine disruptors interferes with the synthesis, release, transport and metabolic activities of hormones, thus impairing human health significantly. Bisphenol A (BpA), an endocrine disruptor, commonly released into the environment by industrial activities and needs immediate attention. This study aims at investigating the process and prospects of deploying bio-electrochemical systems (BES) for the removal of BpA from artificially contaminated soil using Bacillus subtilis HV-3. The BES was setup with desired operating conditions: initial concentration of BpA (80-150 mg/L), pH (3-11) and applied potential voltage (0.6-1.4 V). Under optimized conditions (initial BpA concentration, 100 mg/L; pH 7; and applied voltage 1.0 V), close to 98% degradation of BpA was achieved. The intermediates produced during degradation were analysed using High performance liquid chromatography-Mass spectrometry and the possible degradation pathway was elucidated. Phytotoxicity studies in the remediated soil with Phaseolus mungo confirmed the environmental applicability of the BES system.


Assuntos
Bacillus subtilis/metabolismo , Compostos Benzidrílicos/isolamento & purificação , Biodegradação Ambiental , Técnicas Eletroquímicas , Fenóis/isolamento & purificação , Compostos Benzidrílicos/metabolismo , Disruptores Endócrinos/análise , Disruptores Endócrinos/isolamento & purificação , Disruptores Endócrinos/metabolismo , Fenóis/metabolismo , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo , Vigna/efeitos dos fármacos
11.
J Biosci Bioeng ; 129(5): 638-645, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31926815

RESUMO

Fermented extracts have evolved to be a potential alternative to synthetic chemicals, owing to their anti-inflammatory and anti-bacterial properties. This study intends to assess the potential of fermented Zanthoxylum schinifolium extract for use in biomedical applications. Probiotic bacteria, Lactobacillus rhamnosus A6-5, were deployed as a seed culture for fermentation. The fermented extract showed greater tyrosinase inhibitory activity and reduced melanin production (58.3%) compared with the raw extract. Cytotoxicity assay inferred that 500 µg/mL is the ideal non-toxic concentration with maximum cell viability. In addition, DAPI staining did not show any damage to the chromatin structure of the cells. The anti-aging property of the fermented extract was confirmed by a decrease in IL-6 content. The fermented extract showed lower MIC (40 mg/mL) and MBC (60 mg/mL), indicating greater anti-bacterial activity than the raw extract. The results confirmed that the fermented Z. schinifolium extract has high biomedical properties compared with the raw extract and can be used as an ideal skin whitening agent.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Lacticaseibacillus rhamnosus/metabolismo , Melaninas/química , Extratos Vegetais/farmacologia , Zanthoxylum/química , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Reatores Biológicos , Linhagem Celular , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lacticaseibacillus rhamnosus/genética , Lacticaseibacillus rhamnosus/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Melaninas/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Células RAW 264.7 , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Estrelas-do-Mar/microbiologia , Zanthoxylum/microbiologia
12.
Chemosphere ; 246: 125810, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31927379

RESUMO

Chelate-assisted phytoextraction is proposed to be an effective approach for the removal of metals from contaminated soil. Organic chelators can improve this biological technique by increasing metal solubility. The aim of this study was to investigate the possibility of improving the phytoextraction of lead (Pb) and zinc (Zn) by the application of panchakavya, a traditional Indian organic formulation. Panchakavya was prepared by fermentation process in open environment using cow dunk, cow ghee, cow urine, cow milk, cow curd, tender coconut water, crude jaggery, and mashed bananas. Soil metal fraction studies indicate that the panchakavya treatment decreased (73%) water-soluble fraction of Pb. Plant growth analysis indicated the application of panchakavya to increase Zea mays fresh root weight, shoot biomass and superoxide dismutase level in Zn contaminated soil. Similarly, a significant increase in the Zn accumulation (12% in shoots and 9% in roots) was observed in panchakavya treated plants. However, when compared to control plants, panchakavya treatment significantly decreased (32% in shoots and 37% in roots) Pb accumulation in Z. mays. Obtained results point out that panchakavya could potentially increase the phytoremediation of Zn in Z. mays.


Assuntos
Biodegradação Ambiental , Chumbo/metabolismo , Poluentes do Solo/metabolismo , Zea mays/metabolismo , Zinco/metabolismo , Biomassa , Quelantes/química , Fertilizantes/análise , Chumbo/análise , Compostos Orgânicos/química , Desenvolvimento Vegetal , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Zea mays/crescimento & desenvolvimento , Zinco/análise
13.
3 Biotech ; 8(7): 300, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29963360

RESUMO

The purpose of this study was to examine if fermentation of purple sweet potato (Ipomoea batatas L.) powder (PSP) by Lactobacillus brevis under green, red, blue, white light-emitting diode (LED) illumination or sunlight might yield functionalized products with good antibacterial, antioxidant activity, and/or cytotoxic activity. The Purple sweet potato (PSP) powder fermented with probiotic bacteria L. brevis under white LED light (1.9 ± 1.80/1.6 ± 0.52), blue LED light (1.4 ± 1.32/1.8 ± 0.83), or sunlight (1.2 ± 1.26/1.5 ± 1.83) for Propionibacterium acne and Staphylococcus epidermidis displayed good to moderate antibacterial activity based on minimum inhibitory concentration (MIC) red, blue, white LED lights and sunlight (80 µg/mL) for P. acne and S. epidermidis, minimum bactericidal concentration red, blue LED lights and sunlight shows (46/48, 61/70, 50/48 µg/mL) for P. acne and S. epidermidis. Antioxidant activity for dark, white, blue and green LED lights for ABTS and white, blue and green Led for DPPH assay resulted in lower activity. Fourier transform infrared spectroscopy was performed to determine the functional groups in the non-fermented (control) and fermented products of PSP powders obtained using different light sources. Sunlight, white, and blue LED light-fermented extracts contained alcohol, acid, and phenol groups, as well as aliphatic amines. The results of this study clearly indicate that fermentation of purple sweet potato with probiotic bacteria under various LED light sources can yield compounds that can be used in cosmetic and value-added food products.

14.
Microbiol Res ; 206: 43-49, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29146259

RESUMO

Pseudomonas and Bacillus species are attractive due to their potential bio-control application against plant bacterial pathogens. Pseudomonas aeruginosa strain D4 and Bacillus stratosphericus strain FW3 were isolated from mine tailings in South Korea. In these potent bacterial strains, we observed improved antagonistic activity against Pseudomonas syringae DC3000. These strains produced biocatalysts for plant growth promotion, and in vivo examination of Solanum lycopersicum included analysis of disease severity, ion leakage, chlorophyll content, and H2O2 detection. In addition, regulation of the defense genes pathogen-related protein 1a (PR1a) and phenylalanine ammonia lyase (PAL) was compared with treated plants and untreated control plants. The results suggest that these two bacterial strains provide protection against plant pathogens via direct and indirect modes of action and could be used as a bio-control agent.


Assuntos
Bacillus/fisiologia , Agentes de Controle Biológico , Doenças das Plantas/prevenção & controle , Pseudomonas syringae , Solanum lycopersicum/microbiologia , Bacillus/classificação , Bacillus/genética , Clorofila/análise , Resistência à Doença/genética , Regulação Bacteriana da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pseudomonas aeruginosa , Pseudomonas syringae/patogenicidade , RNA Ribossômico 16S/genética , República da Coreia , Microbiologia do Solo
15.
3 Biotech ; 7(2): 147, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28597158

RESUMO

Metal nanoparticles obtained from green route are gaining significant prominence as a result of their potential applications in nanomedicine and material engineering. Overall metal nanoparticles studied, silver nanoparticles (AgNPs) clutch prominent place in nanoparticles research field. Herein, we have reported the green synthesis of Saccharum officinarum leaf biomass extract-mediated synthesis of AgNPs. Initial nanoparticle production was confirmed by visual observation as color change from light yellow to bright brown color with yellow shade and spectrophotometrically at 450 nm and the various reaction conditions were optimized. The FTIR spectra of the biomass extract and synthesized AgNPs authorized the presence of phyto constituents as capping agent. The High Resolution-Transmission Electron Microscopy (HR-TEM) analyses confirm the morphology and the average particle size of AgNPs as ~28.2 nm. The crystalline nature oxide state and mean particle diameter of AgNPs were confirmed by X-ray diffraction (XRD) analysis, Selected Area Electron Diffraction (SAED) pattern and face-centered cubic (FCC). The obtained AgNPs show moderate to good antifungal activity against Phytophthora capsici, Colletotrichum acutatum and Cladosporium fulvum as 10, 12 and 14 mm zones of inhibition against synthesized AgNPs at 250 µg/well, respectively.

16.
J Photochem Photobiol B ; 173: 571-579, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28697474

RESUMO

The main objective of this study was to extract natural colorant from purple sweet potato powder (PSPP) via a water bath and ultrasound water bath using acidified ethanol (A. EtOH) as the extraction solvent. When optimizing the colorant extraction conditions of the solvents, acidified ethanol with ultrasound yielded a high extraction capacity and color intensity at pH2, temperature of 80°C, 20mL of A. EtOH, 1.5g of PSPP, time of 45min, and ultrasonic output power of 75W. Subsequently, the colorant was extracted using the optimized conditions for dyeing of textiles (leather, silk, and cotton). This natural colorant extraction technique can avoid serious environmental pollution during the extraction and is an alternative to synthetic dyes, using less solvent and simplified abstraction procedures. The extracted purple sweet potato natural colorant (PSPC) was used to dye leather, silk, and cotton fabrics in an eco-friendly approach with augmented antibacterial activity by in situ synthesis of silver nanoparticles (AgNPs) and dyeing. The optimal dyeing conditions for higher color strength (K/S) values were pH2 and 70°C for 45min. The colorimetric parameters L∗, a∗, b∗, C, and H were measured to determine the depth of the color. The Fourier transform infrared spectroscopy (FTIR) spectra of undyed control, dyed with PSPC and dyed with blend of PSPC and AgNPs treated leather, silk and cotton fabric were investigated to study the interaction among fiber type, nanoparticles, and dye. The structural morphology of leather and silk and cotton fabrics and the anchoring of AgNPs with elemental compositions were investigated by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS). The dry and wet rubbing fastness for dye alone and dye with nanoparticles were grade 4-5 and 4, respectively. Thus, the results of the present study clearly suggest that in situ synthesis of AgNPs along with dyeing should be considered in the development of antimicrobial textile finishes.


Assuntos
Antibacterianos/química , Corantes/química , Ipomoea batatas/química , Nanopartículas Metálicas/química , Prata/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Corantes/farmacologia , Concentração de Íons de Hidrogênio , Ipomoea batatas/metabolismo , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Varredura , Sonicação , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus epidermidis/efeitos dos fármacos , Temperatura , Têxteis
17.
FEMS Microbiol Lett ; 364(23)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29069329

RESUMO

Phytopathogenic bacteria have caused significant damage to agricultural crops in both controlled and open cultivation practices, imposing heavy losses to farmers. Thereby, the goal of this study was to evaluate Pseudomonas aeruginosa and Bacillus stratosphericus isolated from soil has antagonistic activity against bacterial phytopathogens with the potential to control plant diseases. Isolated novel strains of P. aeruginosa and B. stratosphericus showed broad spectrum of antagonistic activity against five bacterial phytopathogens. Antagonistic activity was examined under optimized pH (8 and 7), carbon sources (lactose and starch), nitrogen sources (ammonium chloride, peptone and ammonium nitrate) for P. aeruginosa and B. stratosphericus, respectively, and biocatalyst production (chitinase, protease and amylase) was studied. Additionally, up-regulation of defense-related genes (PR-1a and PAL) was studied in tomato plants treated with P. aeruginosa and B. stratosphericus. The induction of defense-related genes in tomato plant was triggered after 12 h treatment with a cell concentration of 0.20 O.D. for P. aeruginosa and 0.21 O.D. for B. stratosphericus during treatment period. Broad spectrum antagonistic activity was observed due to antibiotic and siderophore production by P. aeruginosa and B. stratosphericus.


Assuntos
Bacillus , Agentes de Controle Biológico , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Pseudomonas aeruginosa , Bacillus/classificação , Bacillus/genética , Bacillus/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/microbiologia , Proteínas de Plantas/genética , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Microbiologia do Solo
18.
3 Biotech ; 7(1): 72, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28452017

RESUMO

In the present study, the use of silver oxide nanoparticles (Ag2O NPs) synthesized using Ficus benghalensis prop root extract (FBPRE) as a reducing and stabilizing agent is reported and evaluated for its antibacterial activity against dental bacterial strains. The effects of pH, extract concentration, metal ion concentration, and contact time were studied to confirm the optimum production of Ag2O NPs. Our results suggest that, by increasing the extract concentration and the time frame, there will be a significant increase in the formation of nanoparticles. The UV-vis adsorption spectra show the absorbance peak in the range of 430 nm, and FTIR spectral peaks indicate that the phytochemicals in the extract are responsible for the formation of the nanoparticles. The HR-TEM image, SAED, and XRD pattern confirmed the morphology (spherical), silver oxide 42.7 nm and silver 51.4 nm, and crystalline nature of the obtained nanoparticles, respectively. The blend of FBPRE and Ag2O NPs showed excellent antibacterial activities against the two-dental bacteria Streptococcus mutans and Lactobacilli sp. The study results suggest that the blend of synthesized Ag2O NPS and FBPRE will be useful in tooth paste as a germicidal agent after extensive investigation with animal models.

19.
J Photochem Photobiol B ; 159: 229-36, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27085055

RESUMO

The aim of this study was to introduce novel Sn, Cu, Hg, and Ag nanopowders (NPs) and a composite nanopowder (NP) synthesized using Salvia miltiorrhiza Bunge (SM) root extract as a reducing and capping agent to improve the antibacterial property of dental filling materials. All of the NPs obtained were characterized using a scanning transmission electron microscope (STEM), and energy dispersive X-ray (EDX) spectrum imaging was performed to map the elemental distributions of the NP composite. Fourier transform infrared (FTIR) spectroscopy was performed to identify the role of various functional groups in all of the obtained NPs and the phyto-compound responsible for the reduction of various metal ions. The X-ray diffraction (XRD) patterns clearly illustrated the crystalline phase of the synthesized NP. The antibacterial properties of the synthesized Sn, Cu, Hg, Ag, composite NP, SM root extract, and commercial amalgam powder were evaluated. The Cu, composite NP, SM root extract and Ag NP displayed excellent antibacterial activity against dental bacteria Streptococcus mutans and Lactobacillus acidophilus. The results of this study require further evaluation for signs of metal toxicity in appropriate animal models. However, the results are encouraging for the application of metal NPs as suitable alternatives for antibiotics and disinfectants, especially in dental filling materials.


Assuntos
Antibacterianos/administração & dosagem , Boca/microbiologia , Nanoestruturas , Pós , Técnicas In Vitro , Análise Espectral/métodos
20.
J Photochem Photobiol B ; 162: 93-99, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27348063

RESUMO

We present the simple, eco-friendly synthesis of silver nanoparticles (AgNPs) using sunlight or green, red, blue, or white LED light together with Dryopteris crassirhizoma rhizome extract (DCRE) as the reducing and capping agent. The preliminary indication of AgNP production was a color change from yellowish green to brown after light exposure in the presence of DCRE. Optimization of parameters such as pH, inoculum dose, and metal ion concentration played an important role in achieving nanoparticle production in 30min. The spectroscopic and morphological properties of AgNPs were characterized using UV-Vis spectroscopy through the presence of a characteristic surface plasmon resonance (SPR) band for AgNPs, Fourier transform infrared spectroscopy (FT-IR), high-resolution transmission electron microscopy (HR-TEM), and X-ray diffraction (XRD). The FT-IR results indicated that the phytochemical present in DCRE was the probable reducing/capping agent involved in the synthesis of AgNPs, and light radiation enhanced nanoparticle production. HR-TEM revealed that the AgNPs were almost spherical with an average size of 5-60nm under all light sources. XRD studies confirmed the face cubic center (fcc) unit cell structure of AgNPs. The synthesized AgNPs showed good antimicrobial activity against Bacillus cereus and Pseudomonas aeruginosa. This study will bring a new insight in ecofriendly production of metal nanoparticles.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Fotobiologia , Prata/química , Antibacterianos/farmacologia , Microscopia Eletrônica de Transmissão , Análise Espectral/métodos
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