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Background: The utilization of medicinal plants and their drugs have the advantage of reducing side effects compared with manufactured antimicrobials. Artificial drugs have unpleasant side effects, further, the number of drug resistant pathogens is increasing, thus huge challenge for control of resistant pathogens. Therefore, the current research explores the potential of partially purified bioactive compounds from Dodonaea viscosa against certain human pathogens. Methods: Healthy leaves of D. viscosa (L.) were collected, extracted and optimized with different solvents. Preliminary phytochemical screening of the extracts was done and antibacterial activities were tested against human pathogens. The active crude extract was further purified by column chromatography and the homogeneity was confirmed by thin layer chromatography (TLC). The partially purified compounds were screened further for antibacterial, antibiofilm and anticancer activities. Results: The crude ethanol extract of D. viscosa leaves showed the presence of phytochemical like tannins, alkaloids, flavanoids, terpenoids, glycosides, steroids and phenols. Ethanol extract exhibited the maximum zone of inhibition (11 mm) against S. agalactiae, B. cereus, S. typhi and E. coli at 15 mg when compared with other bacteria. Column chromatography fractions Dv12 and Dv20 exhibited the maximum zone of inhibition against B. cereus. 1000 μg of Dv12 partially purified compound against streptococcus isolates in glass test tube showed biofilm inhibition range of 34.4%–63.1%. Whereas B. cereus, S. aureus, S. typhi, and K. pneumoniae showed 31.1%–53.6% biofilm inhibition compared to curcumin control. Active fractions of Dv12 and Dv20 increased concentration confirmed that the gradual decrease in cell density and possesses growth inhibition towards A 549 human lung adenocarcinoma cells. Conclusion: We have extracted the bioactive compounds from D. viscosa (L.) leaves and tested the activity of a partially purified compound against human pathogenic bacteria, biofilm formation and cytotoxicity against A 549 human lung adenocarcinoma cells. The purified bioactive compounds might be used as therapeutic agents against different microbial infections such as skin infection, throat infection and other infectious diseases.

Saniya Alwani,1 Randeep Kaur,1 Deborah Michel,1 Jackson M Chitanda,2 Ronald E Verrall,3 Chithra Karunakaran,4 Ildiko Badea1 1Drug Design and Discovery Research Group, College of Pharmacy and Nutrition, 2Department of Chemical & Biological Engineering, 3Department of Chemistry, University of Saskatchewan, 4Canadian Light Source, Saskatoon, SK, Canada Purpose: Nanodiamonds (NDs) are emerging as an attractive tool for gene therapeutics. To reach their full potential for biological application, NDs should maintain their colloidal stability in biological milieu. This study describes the behavior of lysine-functionalized ND (lys-ND) in various dispersion media, with an aim to limit aggregation and improve the colloidal stability of ND-gene complexes called diamoplexes. Furthermore, cellular and macromolecular interactions of lys-NDs are also analyzed in vitro to establish the understanding of ND-mediated gene transfer in cells. Methods: lys-NDs were synthesized earlier through covalent conjugation of lysine amino acid to carboxylated NDs surface generated through re-oxidation in strong oxidizing acids. In this study, dispersions of lys-NDs were prepared in various media, and the degree of sedimentation was monitored for 72 hours. Particle size distributions and zeta potential measurements were performed for a period of 25 days to characterize the physicochemical stability of lys-NDs in the medium. The interaction profile of lys-NDs with fetal bovine serum showed formation of a protein corona, which was evaluated by size and charge distribution measurements. Uptake of lys-NDs in cervical cancer cells was analyzed by scanning transmission X-ray microscopy, flow cytometry, and confocal microscopy. Cellular uptake of diamoplexes (complex of lys-NDs with small interfering RNA) was also analyzed using flow cytometry. Results: Aqueous dispersion of lys-NDs showed minimum sedimentation and remained stable over a period of 25 days. Size distributions showed good stability, remaining under 100 nm throughout the testing period. A positive zeta potential of >+20 mV indicated a preservation of surface charges. Size distribution and zeta potential changed for lys-NDs after incubation with blood serum, suggesting an interaction with biomolecules, mainly proteins, and a possible formation of a protein corona. Cellular internalization of lys-NDs was confirmed by various techniques such as confocal microscopy, soft X-ray spectroscopy, and flow cytometry. Conclusion: This study establishes that dispersion of lys-NDs in aqueous medium maintains long-term stability and also provides evidence that lysine functionalization enables NDs to interact effectively with the biological system to be used for RNAi therapeutics. Keywords: colloidal stability, particle size, zeta potential, protein corona, diamoplex, microscopy, flow cytometry

Diphenylamine (DPA) in ethanol on the surface of ZrO2 undergoes photoinduced oxidative transformation yielding N-phenyl-p-benzoquinonimine (PBQ). The light-induced transformation on ZrO2 enhances with [DPA], ZrO2-loading, airflow rate and photon flux. The formation of PBQ on ZrO2 is larger on illumination at 254 nm than at 365 nm. The ZrO2 is reusable without any treatment. The mechanism of light-induced oxidative transformation of DPA on ZrO2 has been discussed with appropriate kinetic law. ZnO and ZnS enhance the UV light-induced transformation of DPA on ZrO2 indicating synergism.

The present work has been investigated for important medicinal properties of Acalypha indica (L). A. indica crude extract was obtained, significant phytochemicals and antibacterial activity substance for the control of numerous antibiotic resistance bacteria such as Escherichia coli, Salmonella typhi, Staphylococcus epidermidis, Bacillus cereus, Staphylococcus marcescens, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes and Streptococcus dysgalactiae. Antibacterial activity of A. indica was performed using the crude extract on Muller-Hinton agar with and without 5% sheep blood by the well diffusion method. We found Ethanol is the most favorable solvent for maximum amount of A. indica extract followed by Acetone, however acetone has more antimicrobial activity. Furthermore, we found Benzene and Diethyl ether are low yielding solvent for A. indica extract. A. indica extract on antimicrobial activity showed remarkable activity in S. typhi, B. cereus followed by S. epidermidis. Eight, phytochemicals tested in A. indica extract showed the existence of tannin, saponin, alkaloid, flavonoid and phenol. Petroleum ether and ethyl acetate solvent (4.2:0.8), was most optimum for the separation of more compounds by TLC analysis. In A. indica four major spots were detected, of these, two major spots were scrabbled from the TLC plates and checked for antimicrobial activity against B. cereus pathogen. B. cereus was selected based on our preliminary results, which showed significant activity among other pathogens. [ABSTRACT FROM AUTHOR]

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In this article the author opines that hospital awareness rather than public awareness is key to promote organ donation in India. Topics include hospital administrators are reluctant to do so as it could lead to their ‘bad reputation'; elsewhere they cite ethical considerations based on conflicts of interest as another factor and the demand for organ transplantation is limited because it is expensive.

Abstract: Rutile SnO2 nanocrystals have been synthesized by sonochemical and hydrothermal methods. Sonochemically obtained crystals possess compressive strain and hydrothermally prepared crystals have tensile strain. Polyethylene glycol 20,000 provides spherical shape to the particles in hydrothermal synthesis but fails to give finite shape to the particles in sonochemical synthesis. The direct band gap of sonochemically prepared SnO2 is much larger than that of hydrothermally obtained one. However, the indirect band gaps of the oxides do not differ significantly. The photoluminescence spectra of both the oxides are similar. The solid state complex impedance spectra of sonochemically and hydrothermally synthesized SnO2 are different; while the former displays a depressed semicircular arc the latter shows a linear relationship between Z″ and Z′. Hydrothermally prepared SnO2 is more photocatalytic than sonochemically obtained SnO2. However, the two oxides do not differ in their bactericidal activities. [Copyright &y& Elsevier]

Abstract: Two percent Cu-doped TiO2 nanoparticles were prepared by a modified ammonia-evaporation-induced synthetic method, calcined at 450°C, and characterized by powder X-ray diffraction, energy dispersive X-ray analysis, ESR spectroscopy, scanning electron microscopy, UV–visible diffuse reflectance spectrum, photoluminescence spectroscopy, and electrochemical impedance spectroscopy. Doping shifts the optical absorption edge to the visible region but increases the charge-transfer resistance and decreases the capacitance. Under visible light, the composite nanoparticles very efficiently catalyze the disinfection of Escherichia coli. The prepared oxide is selective in photocatalysis; under UV light, its photocatalytic activity to degrade sunset yellow, rhodamine B, and methylene blue dyes is less than that of the undoped one. [ABSTRACT FROM AUTHOR]

Abstract: Oxalic acid is photooxidized on Pr6O11 surface under UV-A light and the reaction follows first-order kinetics with a linear dependence on the photon flux. The photonic efficiency is higher with UV-C light than with UV-A light. While TiO2, ZnO, CuO, Bi2O3, and Nb2O5 individually photocatalyze the oxidation, each semiconductor, when present along with Pr6O11, shows enhanced oxidation indicating interparticle hole-jump from the band gap-excited semiconductor to oxalic acid-adsorbed on Pr6O11. The photonic efficiency of the oxidation on Pr6O11 surface is of the order: formic acid>oxalic acid>acetic acid; citric acid is unsusceptible to oxidation. [Copyright &y& Elsevier]

Abstract: The photooxidation of aniline to azobenzene on TiO2 (anatase) in ethanol using solar and UV (365nm) lights was investigated as a function of [aniline], catalyst loading, airflow rate, solvent composition, etc. The catalyst shows sustainable photocatalytic activity. The photocatalysis is larger with illumination at 254nm than at 365nm. Electron donors like triphenylphosphine, diphenylamine and hydroquinone facilitate the oxidation. Azide ion, a singlet oxygen quencher, fails to inhibit the catalysis. The photooxidation occurs in a number of organic solvents. The mechanism of photocatalysis is discussed and the product formation analyzed using a kinetic model. [Copyright &y& Elsevier]

Abstract: ZrO2 photocatalyzes the oxidation of aniline to azobenzene. The oxidation with natural sunlight and UV irradiation (365nm) in ethanol was investigated as a function of [aniline], catalyst loading, airflow rate, solvent composition, etc. The photocatalyst exhibits sustainable catalytic activity. The product formation is larger with illumination at 254nm than at 365nm. Electron donors like triphenylphosphine, diphenylamine and hydroquinone enhance the photocatalysis. Singlet oxygen quencher, azide ion does not inhibit the catalysis. The photocatalysis occurs in protic as well as aprotic solvents. The mechanism of photocatalysis is discussed and the product formation examined using a kinetic model. TiO2, V2O5, ZnO, Fe2O3, CdO, CdS and Al2O3 also photocatalyze the oxidation of aniline to azobenzene; with UV light of wavelength 254nm ZrO2 is more efficient than other photocatalysts studied, the photocatalytic activities are of the order ZrO2 >ZnO>V2O5 >Fe2O3 >CdS>Al2O3 >CdO>TiO2. However, ZrO2 loses its edge over others on illumination at longer wavelength (365nm) and with sunlight. [Copyright &y& Elsevier]