Culture Method-Dependent Variation in the Sensitivity of Escherichia coli to Silver Nanoparticles

Preparation of various metal nanoparticles using plant extracts has been well studied in recent years. In this study, we found that nanoparticles synthesized using the extracts of the inflorescence of Cocos nucifera exhibited differential inhibitory activity against Escherichia coli depending on the nature of the bacterial culture source. Incorporation of silver nanoparticles (Ag-NPs) into the nutrient broth culture of E. coli resulted in poor inhibitory activity. However, when the silver nanoparticles are added to nutrient agar plates used for culture of E. coli, effective inhibition was observed. Additionally, E. coli in broth culture resisted the inhibitory effects of Ag-NPs by forming aggregates of bacterial cells. The aggregates then generated a protective zone around the colonies to prevent the entry of Ag-NPs, and the bacterial cells multiplied without inhibition by the Ag-NPs. These differential effects of Ag-NPs on E. coli culture grown in nutrient broth and on nutrient agar plates indicated that E. coli in broth culture formed aggregates of cells to develop a biofilm for protection against toxins probably via the quorum sensing mechanism

Ekstrakcja barwników z Petrocarpus santalinus i barwienie naturalnych włókien przy użyciu różnych zapraw farbiarskich

Aqueous extraction of natural dyes from Petrocarpus santalinus tree wood and dyeing of the following natural fibres: banana fibre, screw fine fibre, pineapple fibre, sisal fibre, korai and palm leaf using various mordants to fix the colour in the fibre materials were performed. Salt, sodium bicarbonate, oxalic acid, tannic acid, ferrous ammonium sulphate, stannous chloride (tin metal powder), alum and tamarind (Tamarindus indica) were used as a mordant for the dying of the natural fibres. Petrocarpus santalinus dye was effectively dyed on natural fibres using different mordants, producing different colours like tomato, maroon, orange red, chocolate, brown, quarry red, black, brick red, tile red, terra colla, sunbaked clay, gray, brick red, victorian red, firebrick, brown, crimson and orange, using these mordants.W artykule omówiono wykonanie wodnej ekstrakcji naturalnych barwników z drzewa Petrocarpus santalinus oraz barwienie włókien naturalnych, m.in. bananowca, ananasa, sizalu, korai i liści palmowych przy zastosowaniu różnych zapraw farbiarskich, których użycie miało na celu utrwalenie koloru w materiałach włóknistych. Jako zapraw farbiarskich użyto soli, wodorowęglanu sodu, kwasu szczawiowego, kwasu garbnikowego, siarczanu żelazowo-amonowego, chlorku cyny (proszek cyny metalicznej), ałunu i tamaryndowca (Tamarindus indica). Włókna naturalne skutecznie zabarwiono barwnikiem Petrocarpus santalinus przy użyciu różnych zapraw uzyskując różne kolory takie jak: pomidorowy, bordowy, pomarańczowy, czerwony, czekoladowy, brązowy, czarny, czerwony ceglany, terra colla, glinka opalana, szara, ceglastoczerwona, wiktoriański czerwony, ognisty, brązowy, szkarłatny i pomarańczowy

Green synthesis of silver nanoparticles from the extract of the inflorescence of Cocos nucifera (Family: Arecaceae) for enhanced antibacterial activity

Green synthesis of nanoparticles using plant source has been given much importance. In the present study, silver nanoparticles (AgNPs) were synthesized using the ethyl acetate and methanol (EA: M 40:60) extracts of the inflorescence of the tree Cocous nucifera. The synthesized nanoparticles were characterized by UV-visible spectroscope, FTIR and TEM analysis. The particle size of the synthesized AgNPs was 22 nm as confirmed by TEM. The qualitative assessment of reducing potential of the extracts of inflorescence indicated the presence of reducing agents. Synthesized AgNPs exhibited significant antimicrobial activity against human bacterial pathogens viz., Klebsiella pneumoniae, Bacillus subtilis, Pseudomonas aeruginosa and Salmonella paratyphi

Spectral Studies of UV and Solar Photocatalytic Degradation of AZO Dye and Textile Dye Effluents Using Green Synthesized Silver Nanoparticles

The photocatalytic degradation of the chemical dye AZO and dye effluents in different time duration has been investigated using biologically synthesized silver nanoparticles. Dye industry effluents and AZO dye undergo degradation to form harmless intermediate and colourless products following irradiation by UV and solar light in the presence of green synthesized silver nanoparticles. The degree of degradation was tested under the experimental conditions such as PH, temperature, and absorbance of the dye in UV and solar light was measured. The degradation was higher in the UV light source than in the solar light source. Green synthesized silver nanoparticles in the UV light source were found to expedite the dye degradation process

Synthesis of silver nanoparticles from natural derived embelin compound and their uses in mercury degradation under solar light

The present study deals with the isolation of embelin compound from Embelia ribes (Burm f). The isolated compounds were confirmed by UV/Vis spectrophotometer, ^1 H NMR and ^13 C NMR spectra. In absorption at 275 nm in UV/Vis spectra, peak range at 5.7ppm in ^1 H NMR and peak value at 28.52, 29.35, 31.73ppm in ^13 C NMR to confirmed the isolated compound are embelin. This isolated compound used as a reducing agent for silver nanoparticles synthesis. The synthesized En-AgNPs were morphologically and structurally confirmed by UV/Vis spectrophotometer, FT-IR, SEM, EDAX, and XRD. The synthesized silver nanoparticles are spherical in shape with the size of <100 nm. The embelin based silver nanoparticles used to degrade the toxic metal like Mercury under solar light. The toxic metal Mercury was degraded within 60 min by En-AgNPs under solar photo catalytic degradation