The antibacterial activity of ZnO nanoparticles has been investigated and presented in this paper. Nanoparticles were prepared via non-hydrolytic solution process using zinc acetate di-hydrate (Zn(CH(3)COO)(2).2H(2)O) and aniline (C(6)H(5)NH(2)) in 6 h refluxing at approximately 65 degrees C. In the presence of four pathogens such as Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Klebsiella pneumoniae, the antibacterial study of zinc oxide nanoparticles were observed. The antibacterial activity of ZnO nanoparticles (ZnO-NPs) were studied by spectroscopic method taking different concentrations (5-45 microg/ml) of ZnO-NPs. Our investigation reveals that the lowest concentration of ZnO-NPs solution inhibiting the growth of microbial strain is found to be 5 microg/ml for K. pneumoniae, whereas for E. coli, S. aureus, and S. typhimurium, it was calculated to be 15 microg/ml. The diameter of each ZnO-NPs lies between "20 and 30 nm" as observed from FESEM and transmission electron microscopy images. The composition of synthesized material was analyzed by the Fourier transform infrared spectroscopy, and it shows the band of ZnO at 441 cm(-1). Additionally, on the basis of morphological and chemical observations, the chemical reaction mechanism of ZnO-NPs was also proposed.

Microorganisms, their cell filtrates, and live biomass have been utilized for synthesizing various gold nanoparticles. The shape, size, stability as well as the purity of the bio synthesized nanoparticles become very essential for application purpose. In the present study, gold nanoparticles have been synthesized from the supernatant, live cell filtrate, and biomass of the fungus Penicillium brevicompactum. The fungus has been grown in potato dextrose broth which is also found to synthesize gold nanoparticles. The size of the particles has been investigated by Bio-TEM before purification, following purification and after storing the particles for 3 months under refrigerated condition. Different characterization techniques like X-ray diffraction, Fourier transform infrared spectroscopy, and UV-visible spectroscopy have been used for analysis of the particles. The effect of reaction parameters such as pH and concentration of gold salt have also been monitored to optimize the morphology and dispersity of the synthesized gold nanoparticles. A pH range of 5 to 8 has favored the synthesis process whereas increasing concentration of gold salt (beyond 2 mM) has resulted in the formation of bigger sized and aggregated nanoparticles. Additionally, the cytotoxic nature of prepared nanoparticles has been analyzed using mouse mayo blast cancer C(2)C(12) cells at different time intervals (24, 48, and 72 h) of incubation period. The cells are cultivated in Dulbecco's modified Eagle's medium supplemented with fetal bovine serum with antibiotics (streptopenicillin) at 37°C in a 5% humidified environment of CO(2). The medium has been replenished every other day, and the cells are subcultured after reaching the confluence. The viability of the cells is analyzed with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide method.

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This paper presents the fabrication and characterization of zinc oxide micro-flowers and their antibacterial activity. The micro-flowers of zinc oxide composed of hexagonal nanorods have been prepared via solution process using precursor zinc acetate di-hydrate and sodium hydroxide in 3 h of refluxing time at ~90°C. The antibacterial activities of grown micro-flowers were investigated against four pathogenic bacteria namely S. aureus, E. coli, S. typhimurium and K. pneumoniae by taking five different concentrations (5–45 μg/ml) of ZnO micro-flowers (ZnO-MFs). Our investigation reveals that at lowest concentration of ZnO-MFs solution inhibiting the growth of microbial strain which was found to be 5 μg/ml for all the tested pathogens. Additionally, on the basis of morphological and chemical observations, a chemical reaction mechanism of ZnO-MFs composed of hexagonal nanorods was also proposed.

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The symptoms of Staphylococcal scalded skin syndrome (SSSS) include blistering of skin on superficial layers due to the exfoliative toxins released from Staphylococcus aureus. After the acute exfoliation of skin surface, erythematous cellulitis occurs. The SSSS may be confined to few blisters localized to the infection site and spread to severe exfoliation affecting complete body. The specific antibodies to exotoxins and increased clearence of exotoxins decrease the frequency of SSSS in adults. Immediate medication with parenteral anti-staphylococcal antibiotics is mandatory. Mostly, SSSS are resistant to penicillin. Penicillinase resistant synthetic penicillins such as Nafcillin or Oxacillin are prescribed as emergency treatment medicine. If Methicillin-resistant Staphylococcus aureus (MRSA) is suspected), antibiotics with MRSA coverage (e.g., Vancomycin or Linezolid) are indicated. Clindamycin is considered as drug of choice to stop the production of exotoxin from bacteria ribosome. The use of Ringer solution to to balance the fluid loss, followed by maintainence therapy with an objective to maintain the fluid loss from exfoliation of skin, application of Cotrimoxazole on topical surface are greatlly considered to treat the SSSS. The drugs that reduce renal function are avoided. Through this article, an attempt has been made to focus the source, etiology, mechanism, outbreaks, mechanism, clinical manisfestation, treatment and other detail of SSSS.

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In the present paper, facile synthesis of Ag@ZnO core-shell nanocomposites is reported where zinc oxide is coated on biogenic silver nanoparticles synthesized using Andrographis paniculata and Aloe vera leaf extract. Structural features of as synthesized nanocomposites are characterized by UV-visible spectroscopy, XRD, and FTIR. Morphology of the above core-shell nanocomposites is investigated by electron microscopy. As synthesized nanocomposite material has shown antimicrobial activity against Candida krusei, which is an opportunistic pathogen known to cause candidemia. The possible mode of activity of the above material has been studied by in-vitro molecular techniques. Our investigations have shown that surface coating of biogenic silver nanoparticles by zinc oxide has increased its antimicrobial efficiency against Candida krusei, while decreasing its toxicity towards A431 human epidermoid carcinoma cell lines.