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One fourth of the global mortalities is still caused by microbial infections largely due to the development of resistance against conventional antibiotics among pathogens, the resurgence of old infectious diseases and the emergence of hundreds of new infectious diseases. The lack of funds and resources for the discovery of new antibiotics necessitates the search for economic and effective alternative antimicrobial agents. Metal and metal oxide nanoparticles including silver and zinc oxide exhibit remarkable antimicrobial activities against pathogens and hence are one of the most propitious alternative antimicrobial agents. These engineered nanomaterials are approved by regulatory agencies such as USFDA and Korea’s FITI, for use as antimicrobial agents, supplementary antimicrobials, food packaging, skin care products, oral hygiene, and for fortifying devices prone to microbial infections. Nevertheless, detailed studies, on molecular and biochemical mechanisms underlying their antimicrobial activity are missing. To take the full advantage of this emerging technology selective antimicrobial activity of these nanoparticles against pathogens should be studied. Optimization of these nanomaterials through functionalization to increase their efficacy and biocompatibility is also required. Urgent in vivo studies on the toxicity of nanomaterials at realistic doses are also needed before their clinical translation. [ABSTRACT FROM AUTHOR]

Abstract: The in vitro interaction of the organophosphorous insecticide (OPs) phorate with calf thymus DNA (ctDNA), and its potential to cause changes in cell cycle, membrane damage, and cytotoxicity leading to cell death (necrosis) was investigated in human amnion epithelial (WISH) cells. Fluorescence quenching revealed high binding affinity (K a =5.62×104 M−1) of phorate to ctDNA. Molecular modeling of the phorate–ctDNA interaction suggested the binding of phorate at AT rich regions on minor groove of DNA. The interaction ensued alkylation of the N-6, N-7 of adenine and C-4 carbonyl oxygen of thymine. Binding of phorate was stronger in the presence of the transition metal ion copper II (Cu2+), and has accentuated the destabilization of the DNA secondary structure. A discernable change in the voltammetric E 1/2 (E 0′) with lesser cathodic (i pc) and anodic (i pa) peak currents confirmed the formation of phorate–DNA and phorate–DNA–Cu (II) association complexes. Furthermore, the MTT and NRU assays demonstrated substantial phorate cytotoxicity due to loss of mitochondrial and lysosomal membrane integrity, and reduction in mitochondrial membrane potential (ΔΨm) of treated WISH cells. Cell cycle analysis of WISH cells treated with 1000μM phorate exhibited 13.7-fold (p <0.01) augmentation in the sub-G1 peak. Annexin V-PE and 7-ADD staining of phorate treated cells reaffirmed the development of late apoptotic or necrotic cell population in a concentration dependent manner. Thus, this study demonstrated the phorate induced DNA structural alterations and cellular damage in cultured human cells. [Copyright &y& Elsevier]

Abstract: A fungal strain, KSU-09, isolated from the roots of date palm (Phoenix dactylifera), was identified as Amylomyces rouxii based on sequence analysis of the internal transcribed spacer (ITS) region of its rRNA genes. Mycelia-free water extracts obtained from mycelium suspended in water for 72h facilitated the production of stable, predominantly monodispersed and spherical silver nanoparticles (AgNPs) in the size range of 5–27nm upon addition of 1mM silver nitrate, as determined by the XRD, AFM and TEM. The AgNPs exhibited antimicrobial activity against Shigella dysenteriae type I, Staphylococcus aureus, Citrobacter sp., Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans and Fusarium oxysporum. Thus, the strain KSU-09 could be used for simple, non-hazardous and efficient synthesis of antimicrobial AgNPs. [ABSTRACT FROM AUTHOR]

The heavy metal-resistant bacterial strain SJ-101 has been isolated from fly ash contaminated soil. Based on the morphological and biochemical characteristics, the isolate SJ-101 was presumptively identified as Bacillus sp. The adsorption isotherms revealed the absolute adsorption capacity (Q°) of 244 mg Ni g−1 dry cell mass vis-à-vis 161 mg Ni g−1 synthetic resin (Amberlite IR-120). The higher relative adsorption capacity (KF) of 7.37, and the intensity of adsorption (1/n) of 0.58 with dry cell biomass suggested higher affinity of Bacillus cells towards nickel ions. The data conform to the Langmuir adsorption model relatively better than the Freundlich model. The thermodynamic parameters indicated the feasibility, endothermic, and interactive nature of nickel adsorption process on the cell surface. Higher Ni tolerance and sorption capacity of Bacillus sp. SJ-101, explicitly signifies its implications in Ni bioremediation process. [ABSTRACT FROM AUTHOR]

The interactions of calf thymus DNA with tetracycline (TC), 7-chlorotetracycline (CTC) and 6-dimethyl-7-chlorotetracycline (DMTC) were assessed employing spectrofluorometric and circular dichroism (CD) techniques. The Scatchard analysis revealed relatively lesser binding affinity of TC (Ka=1.2×107 l mol−1) vis-a-vis CTC (Ka=3.4×107 l mol−1) and DMTC (Ka=3.0×107 l mol−1) with DNA. The data suggested both the intercalative and electrostatic nature of binding between the tetracyclines and DNA. The presence of Cu(II) augmented the interaction of tetracyclines with DNA, and resulted in red shift by 12 nm in CD spectra of tetracycline. The molar ellipticity (θ) also changed significantly for CTC and DMTC. The data unequivocally demonstrated the DNA binding potential of tetracyclines both in the presence and absence of Cu(II) ions in dark. The enhanced binding of tetracyclines in presence of Cu(II), ensuing conformational changes in DNA secondary structure to a varying extent, reflects differential reactivity of ligand chromophores. [Copyright &y& Elsevier]

Phylogenetic characterization of soil isolate NJ-15, based on sequence homology of a partial 746-bp fragment of 16SrDNA amplicon, with the ribosomal database sequences (http://www.msu.edu/RDP/cgis/phylip.cgi), validated the strain as Pseudomonas aeruginosa. The strain NJ-15 produced a substantial amount of indole acetic acid (IAA) in tryptophan-supplemented medium. Besides, the strain also exhibited significant production of both the siderophore and hydrogen cyanide (HCN) on chrome azurol S and King's B media, respectively. The data revealed lower HCN production under iron-limiting conditions vis-à-vis higher HCN release with iron stimulation. Significant growth inhibition of phytopathogenic fungi occurred in the order as Fusarium oxysporum > Trichoderma herizum > Alternaria alternata > Macrophomina phasiolina upon incubation with strain NJ-15 cells. Thus, the secondary metabolites producing new Pseudomonas aeruginosa strain NJ-15 exhibited innate potential of plant growth promotion and biocontrol activities in vitro. Correspondence to: J. Musarrat; email: musarratj1@yahoo.com --> [ABSTRACT FROM AUTHOR]

The protein-damaging potential of photosensitized tetracycline hydrochloride alone and in combination with the metal ion Cu(II) was assessed using serum albumin as a model protein. Exposure of tetracycline to white light in an aqueous solution triggered the generation of significant amounts of reactive oxygen species (ROS) and engendered substantial protein damage. The appearance of distinct low-molecular-mass protein bands on 10% SDS-polyacrylamide gel ascertained the tetracycline concentration-dependent fragmentation of albumin. Photoexcited tetracycline in combination with 100 μM Cu(II) enhanced the protein fragmentation process with concurrent increase in free radical production. The significant release of acid-soluble amino groups and carbonyl groups from treated albumin provided quantitative estimation of protein fragmentation at 0–1.0 mM concentrations of tetracycline. Cu(II) ions per se did not cause any perceptible protein damage. The results with free radical quenchers suggested the role of hydroxyl radicals (⋅OH) in tetracycline–Cu(II)-induced protein fragmentation, as no superoxide dismutase (SOD)-mediated quenching effect was noted. The generation of free radicals upon tetracycline photoexcitation and consequent protein fragmentation may be considered as important factors in augmentation of tetracycline-induced phototoxic responses. [Copyright &y& Elsevier]

Species of the genus Rothia that inhabit the oral cavity have recently been implicated in a number of diseases. To minimize their role in oral infections, it is imperative to reduce and/or control the growth and biofilm formation activity of Rothia spp. In this study, two bacterial isolates, Ora-7 and Ora-16, were obtained from the oral cavity of a healthy male subject and identified as Rothia dentocariosa and Rothia mucilaginosa, respectively, using a polyphasic taxonomic approach. Antimicrobial and anti-biofilm formation activities of zinc oxide nanoparticles (ZnO-NPs), of average size 35 nm, were assessed in in vitro assays using Crystal Violet and live and dead staining techniques. The ZnO-NPs exhibited an IC50 value of 53 and 76 µg ml-1 against R. dentocariosa and R. mucilaginosa, respectively. Biofilm-formation assays, performed on the surfaces of polystyrene plates, artificial teeth, and dental prostheses, revealed the efficacy of ZnO-NPs as a potential antibacterial agent for controlling the growth of Rothia isolates in both planktonic form and biofilm. [ABSTRACT FROM AUTHOR]

The existence of microbe free animals or plants in nature is virtually impossible as they and plants have a certain degree of symbiotic association with microbes. This symbiotic association leads to the formation of holobiont (host and its symbionts). This mutual coexistence is not merely at the physical or chemical level but also at the genetic level leading to the emergence of the concept of hologenome (gene pool of host and its associated symbionts). The abundance of symbionts with the associated gene diversity contributes to the fitness of the holobiont under varying environmental conditions. The hologenome theory of evolution considers the dynamic holobiont as a single unit for natural selection and provides a more accommodating view of evolution blending Darwinism and Lamarkism. Additionally, holobionts are providing scientific basis to our understanding of the growing importance of probiotics in human health and in disease management. [ABSTRACT FROM AUTHOR]

Abstract: Optical properties of the interaction between thiophanate methyl and human serum albumin have been investigated for biosensor applications. The interaction between human serum albumin (HSA) and thiophanate methyl (MT) was investigated by UV–Vis absorption spectra and atomic force microscopy. The optical constants (refractive index, absorption index, band gap and dielectric properties) of HSA, MT and MT+HSA films were determined using absorbance, transmittance and reflectance spectra. The refractive index dispersion curve (>530nm) exhibits the normal dispersion. The refractive index of the MT+HSA is higher than both HSA and MT alone due to the highest reflectance of the mixture of MT and HSA. This behavior is indicative of the complex formation between the MT and HSA. [Copyright &y& Elsevier]

Tetracyclines (TCs) in combination with Cu(II) ions exhibited significant DNA damaging potential vis a vis tetracyclines per se. Interaction of tetracyclines with DNA resulted in alkylation at N-7 and N-3 positions of adenine and guanine bases, and caused destabilization of DNA secondary structure. Significant release of acid-soluble nucleotides from tetracycline-modified DNA upon incubation with S1 nuclease ascertained the formation of single stranded regions in the DNA. Also, the treatment of tetracycline-modified DNA with 0.1 and 0.5 M NaOH resulted in 62 and 76% hydrolysis compared to untreated control. Comparative alkaline hydrolysis of DNA modified with tetracycline derivatives showed differential DNA damaging ability in the order as DOTC>DMTC>TC>OTC>CTC. Addition of Cu(II) invariably augmented the extent of tetracycline-induced DNA damage. The alkaline unwinding assay clearly demonstrated the formation of approximately six strand breaks per unit DNA at 1:10 DNA nucleotide/TC molar ratio in the presence of 0.1 mM Cu(II) ions. At a similar Cu(II) concentration, a progressive transformation of covalently closed circular (CCC) (form-I) plasmid pBR322 DNA to forms-II and -III was noticed with increasing tetracycline concentrations. The results obtained with the free-radical quenchers viz. mannitol, thiourea, sodium benzoate and superoxide dismutase (SOD) suggested the involvement of reactive oxygen species in the DNA strand breakage. It is concluded that the tetracycline–Cu(II)-induced DNA damage occurs due to (i) significant binding of tetracycline and Cu(II) with DNA, (ii) methyl group transfer from tetracycline to the putative sites on nitrogenous bases, and (iii) metal ion catalyzed free-radical generation in close vicinity of DNA backbone upon tetracycline photosensitization. Albeit, the DNA alkylation and strand cleavage are repairable lesions, but any defect in the critical repair pathway may augment the damage accumulation and mutagenesis. [Copyright &y& Elsevier]

Interaction of tetracycline (TC) derivatives viz. oxytetracycline, doxycycline, demeclocycline and chlorotetracycline with bovine serum albumin (BSA) and concomitant changes in protein conformation were studied using fluorescence quenching and circular dichroism measurements. Fluorescence data revealed the presence of one to three binding sites on BSA for different TC derivatives. Binding studies with the marker ligands, warfarin and bilirubin, elucidated site-I as a primary binding site for TCs on albumin. Scatchard analysis revealed the binding affinity (Ka) and capacity (n) for these derivatives vary in the range from 0.8 to 3.2×106 l/mole and 1.3–3.4, respectively. Significant reduction (60–45%) in secondary structure (α-helical content) of BSA was noticed upon interaction with different TC derivatives in presence of Cu (II) ions. High affinity binding of TCs with BSA signifies drug stability. However, excessive binding at higher TC concentrations in combination with Cu (II) induces conformational change in protein structure, which may exert detrimental effect on cellular protein. [Copyright &y& Elsevier]

Photosensitization of paraquat with photosynthetically active radiations (PAR) induced substantial production of both the hydroxyl radicals (·OH) and superoxide anions (O2·−) under in vitro conditions. Addition of transition metal ion, Cu (II) enhanced the paraquat-induced ·OH radical production by 1.8-fold. Treatment of bovine serum albumin (BSA) with photosensitized paraquat resulted in a dose dependent fragmentation of protein. The quantitative analysis revealed the release of 73 μM acid soluble amino groups and 450 μM carbonyl groups from treated albumin at the highest albumin–paraquat molar ratio of 1:8 in presence of 200 μM Cu (II). The results with the free radical quenchers such as mannitol and superoxide dismutase (SOD) clearly reflected the involvement of ·OH radicals in protein fragmentation process. The fluorescence data revealed significantly higher binding of paraquat with serum albumin. The binding constants (Ka) and binding capacity (n) of albumin for paraquat were determined to be 3.4×105 l/mole and 12.9, respectively. Fluorescence emission spectra exhibited significant quenching of the intrinsic fluorescence of albumin upon addition of paraquat at increasing molar ratios. This is attributed to induced conformational changes in protein structure upon paraquat interaction at specific sites on albumin molecule. Most likely, the alkyl group transfers occur from N1 and/or N1′ positions of paraquat to the electron rich sites at critical amino acid residues on treated protein. At higher paraquat concentrations, the albumin–paraquat interaction resulted in adduct formation with concurrent protein alkylation and free radical mediated fragmentation. Thus, on the basis of these results, the paraquat–protein interaction leading to alkylation, structural alterations and/or fragmentation of biological macromolecules has been suggested as an important factor for agrochemical-induced toxicity. [Copyright &y& Elsevier]

Nanoparticles are increasingly used in many industrial sectors due to their unique properties, yet their introduction in ecosystems is of concern for health and food security. In particular, the accumulation of nanoparticles in soils may disturb the soil and plant system, possibly inducing a risk for crop production. Here, we review recent advances on nanoparticles in the soil–plant system. We focus on sources, emission, transformation, bioavailability, interactions, phytotoxicity and plant uptake of nanoparticles. We emphasize the genomic, metabolomic and proteomic alterations in plants caused by nanoparticles. Besides negative impacts, benefits of nanoparticles for plant growth are discussed. [ABSTRACT FROM AUTHOR]

• Microwave assisted E. globulus extract (ELE) capped-CuONPs bio-fabrication. • Pro-apoptotic nature of E. globulus extract (ELE) capped-CuONPs in MCF-7 cells. • ELE-CuONPs induced ROS mediated cell cycle dysfunction. • Dose-dependent anti-fungal activities of ELE-CuONPs against A. flavus. This study demonstrates a comprehensive and cost-effective one-step rapid bio-fabrication of Eucalyptus globulus leaf extract (ELE) bio-actives functionalized copper oxide nanoparticles (CuONPs); and analyze its apoptotic and toxic effects in human breast cancer (MCF-7) cells and Aspergillus flavus. The state-of-art characterization data confirmed the thermal-stability of (i) ELE-CuONPs and (ii) surface associated ELE bio-active compounds bearing characteristic functional groups (aromatic OH, polymeric OH, C O, and C O) over a range of conventional temperatures (30 °C–80 °C), and microwave (MW) heat (140 °C). The MW accelerated ELE-CuONPs (16.9 nm) treated (25−100 μg/ml) MCF-7 cells showed a significant (p < 0.05) reduction in viability due to the dysfunction of mitochondrial membrane potential, intracellular ROS accumulation, and disruption in normal cell cycle progression. Moreover, transcriptional up-regulation of mRNA expression of p53 (8.8 fold), bax (1.42 fold), caspase-3 (2.42 fold), and caspase-9 (3.34 fold) genes in the MCF-7 cells confirmed a mechanistic anti-cancer landscape of synthesized ELE-CuONPs. Furthermore, ELE-CuONPs inhibited sclerotia germination and growth of A. flavus. Conclusively, this study is novel in better demonstrating the formation of ELE-CuONPs that meets the principles of green chemistry. These findings can be used to develop strategies for the management of cancer and fungal infections affecting human health. [ABSTRACT FROM AUTHOR]

This study was aimed at producing the eco-friendly, safe, and inexpensive silver (Ag) nanoparticles (NPs) and assessing its antimicrobial activity. Fungal pathogens isolated from diseased leaves and fruits of brinjal and bacterial pathogen obtained from a culture collection were used in this study. Green synthesis of AgNPs was performed and optimized using Azadirachta indica leaf extract. The newly synthesized AgNPs (λmax = 437 nm) showed isotropism in size (crystal size/diameter: 21/29 ± 5 nm) and morphology under transmission and scanning electron microscopy and energy dispersive X-ray analysis. The fourier transform infrared spectroscopy data suggested the role of various aliphatic/aromatic moieties and proteins in AgNPs stabilization. The AgNPs reduced the growth of Penicillium sp. maximally by 92% after 6 days. The sensitivity of test fungi towards AgNPs followed the order: Penicillium sp. (92%) > Fusarium sp. (89%) > Aspergillus sp. (69%). Exposure of Ralstonia solanacearum to AgNPs (MIC/MBC 200/400 µg ml−1) displayed damaged cellular envelopes, bulging of cells, and pit formation. The nucleic acid discharge showed a progressive increase from 8 to 34% (r2 = 0.97). The cellular metabolic activity and surface adhering ability of R. solanacearum were completely lost at 400 µgAgNPs ml−1. Results suggested that the AgNPs synthesized in this study had enough anti-pathogenic potential and could inexpensively and safely be used as a promising alternative to agrochemicals. Moreover, the findings observed in this study is likely to serve as an important indicator for the development of effective nano-control agents which in effect would help to manage some deadly phyto-pathogens capable of causing heavy losses to agricultural production systems. Effective inhibition of phytopathogenic microbes by eco-friendly neem leaf extract mediated silver nanoparticles (AgNPs) [ABSTRACT FROM AUTHOR]

Autosomal recessive spastic ataxia of Charlevoix–Saguenay (ARSACS) is a rare neurodegenerative disorder characterized by the triad of early-onset cerebellar ataxia, peripheral sensorimotor neuropathy, and lower limb spasticity. Here, we present a 28-year-old male patient with symptoms of ARSACS and mild intellectual disability from a consanguineous family of tribal J&K, India. Whole exome sequencing unraveled a novel homozygous frameshift SACS mutation (Cys2869ValfsTer15) in the patient. In addition to the well-established ARSACS imaging features, MRI revealed T2 hyperintense rim around the thalami ("bithalamic stripes") demonstrating that this feature might serve as an additional supportive diagnostic imaging marker for ARSACS. Moreover, retinal nerve fiber layer thickening which has recently been proposed as a diagnostic biomarker for ARSACS was present on routine optic coherence tomography (OCT) also in this patient, indicating that it might indeed present a relatively universal diagnostic biomarker for ARSACS. In sum, our findings extend the geographical distribution of ARSACS to even very remote tribal regions in Asia (such as the Rajouri region of J&K, India) and extend the mutational and imaging spectrum of ARSACS. They provide further support that brain imaging and OCT markers might serve as diagnostic biomarkers for ARSACS in patients with novel SACS mutations, applicable even in remote regions of the world to identify and confirm ARSACS disease. [ABSTRACT FROM AUTHOR]

Abstract This study demonstrates a simple one-pot green method for biosynthesis of terpenoids encapsulated copper oxide nanoparticles (CuONPs) using aqueous leaf extract of Eucalyptus globulus (ELE), as reducing, dispersing, and stabilizing agent. Indeed, the greater attachment and internalization of ELE-CuONPs in Gram-positive and -negative biofilm producing clinical bacterial isolates validated the hypothesis that terpenoids encapsulated CuONPs are more stable and effective antibacterial and antibiofilm agent vis-à-vis commercially available nano and micro sized analogues. Gas chromatography-mass spectroscopy (GC–MS) analysis of pristine ELE identified 17 types of terpenoids based on their mass-to-charge (m/z) ratios. Amongst them four bioactive terpenoids viz. terpineols, 2,6-octadienal-3,7-dimethyl, benzamidophenyl-4-benzoate and β-eudesmol were found associated with the CuONPs as ELE-cap, and most likely involved in the nucleation and stabilization of ELE-CuONPs. Further, the Fourier transformed infrared (FTIR) analysis of ELE-CuONPs also implicated other functional biomolecules like proteins, sugars, alkenes, etc. with ELE terpenoids corona. Flow cytometric (FCM) data exhibited significantly enhanced intracellular uptake propensity of terpenoids encapsulated ELE-CuONPs and accumulation of intracellular reactive oxygen species (ROS), which ensued killing of planktonic cells of extended spectrum β-lactamases (ESβL) producing Escherichia coli -336 (E. coli- 336), Pseudomonas aeruginosa -621 (P. aeruginosa -621) and methicillin-resistant Staphylococcus aureus -1 (MRSA-1) clinical isolates compared to the bare surface commercial nano-CuO and bulk sized CuO. The study for the first-time demonstrated the (i) differential bio-nano interface activities due to ELE surface and varied cell wall composition of test bacterial isolates, (ii) antibacterial effect and biofilm inhibition due to disruption of proteins involved in adhesion and biofilm formation triggered by CuONPs induced intracellular oxidative stress, and (iii) indigenous terpenoids-capped bio-inspired CuONPs are more stable and effective antibacterial and antibiofilm agent as compared with commercially available nano-CuO and bulk-CuO. Graphical abstract Unlabelled Image Highlights • Bio-inspired synthesis of Eucalyptus globulus terpenoids capped CuONPs. • GC–MS and FTIR analyses of Eucalyptus globulus terpenoids corona of CuONPs. • Comparison of capped NP's antibacterial activities with bare nano and bulk analogues. • Comparative account on cellular uptake and ROS generation by TEM, AAS and FCM. • Crystal-violet and CLSM based comparative analyses of biofilm inhibition. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were synthesized using aqueous extract of Nepeta deflersiana plant. The prepared AgNPs (ND-AgNPs) were examined by ultraviolet-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), and energy dispersive spectroscopy (EDX). The results obtained from various characterizations revealed that average size of synthesized AgNPs was 33 nm and in face-centered-cubic structure. The anticancer potential of ND-AgNPs was investigated against human cervical cancer cells (HeLa). The cytotoxic response was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), neutral red uptake (NRU) assays, and morphological changes. Further, the influence of cytotoxic concentrations of ND-AgNPs on oxidative stress markers, reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest and apoptosis/necrosis was studied. The cytotoxic response observed was in a concentration-dependent manner. Furthermore, the results also showed a significant increase in ROS and lipid peroxidation (LPO), along with a decrease in MMP and glutathione (GSH) levels. The cell cycle analysis and apoptosis/necrosis assay data exhibited ND-AgNPs-induced SubG1 arrest and apoptotic/necrotic cell death. The biosynthesized AgNPs-induced cell death in HeLA cells suggested the anticancer potential of ND-AgNPs. Therefore, they may be used to treat the cervical cancer cells. [ABSTRACT FROM AUTHOR]

Abstract Biogenic hematite (α-Fe 2 O 3) nanoparticles (NPs) of average size <10 nm were synthesized using green approach with Aloe vera extract (ALE). The aim of the study was to assess the protective effect of extracellular polymeric substances (EPS) against antibacterial and antibiofilm activities of ALE-α-Fe 2 O 3 NPs in normal EPS producers (pristine) and experimentally modified (low-EPS) Pseudomonas aeruginosa (P. aeruginosa) cells and the mechanism of cell killing. Formation of ALE-α-Fe 2 O 3 NPs has been validated by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier-transformed infrared spectroscopy (FTIR) analysis. The FTIR data suggested the possible role OH group bearing organic compounds of ALE in metal reduction and nucleation of NPs. Gas Chromatography-Mass spectroscopy (GC–MS) analysis revealed the presence of oxime-methoxy-phenyl, ethanone 1-phenyl, hexadecanoic acid, cyclohexanol 2,6-dimethyl, tetracontane, stigmast-5-en-3-ol, cyclohexanol 2,6-dimethyl, and cyclohexasiloxane dodecamethyl on the surface of ALE-α-Fe 2 O 3 NPs. Cell viability assay and SEM imaging revealed significantly greater bacteriostatic and/or bactericidal effect of ALE-α-Fe 2 O 3 NPs in low EPS cells compared to pristine cells or bare-α-Fe 2 O 3 NPs. This is attributed to thinner protective layer of EPS around the low EPS cells, and higher dispersibility and stability of ALE-α-Fe 2 O 3 NPs. Absorption of ALE-α-Fe 2 O 3 NPs and bare-α-Fe 2 O 3 NPs on EPS surface and within EPS matrix was ascertained by atomic absorption spectroscopy (AAS). The results suggest differential internalization of ALE-α-Fe 2 O 3 NPs and bare-α-Fe 2 O 3 NPs in P. aeruginosa cells. The flow cytometry (FCM) results exhibited increased intracellular granularity in low EPS (18.94%) as compared with pristine (10.94%) cells, which signifies the greater internalization of ALE-α-Fe 2 O 3 NPs. Moreover, the proportionate increase in intracellular ROS generation in low EPS (20.47%) via-a-vis pristine (7.56%) cells was observed. Overall, the results elucidate that ALE-α-Fe 2 O 3 NPs-bacterial interaction leads to attachment of NPs to EPS surface, migration within the EPS matrix and penetration into cell, which eventually results in growth inhibition due to intracellular ROS activity. Owing to significant antibacterial and antibiofilm activities, ALE-α-Fe 2 O 3 NPs may serve as a good candidate for clinical management of extended spectrum beta lactamases (ESBL) positive P. aeruginosa. Graphical Abstract Unlabelled Image Highlights • FTIR and GC–MS based analysis of Aloe vera biomolecules adsorbed on to α-Fe 2 O 3 NPs. • Differential antibacterial effect of bare and ALE-capped α-Fe 2 O 3 NPs against pristine and low EPS P. aeruginosa cells. • FCM analysis of uptake of bare and ALE-capped α-Fe 2 O 3 NPs against pristine and low EPS P. aeruginosa cells. • FTIR spectroscopic study of interaction between EPS and α-Fe 2 O 3 NPs. [ABSTRACT FROM AUTHOR]

In this research work, barium titanate nanoparticles (BaTiO 3 NPs) were prepared by a co-precipitation method using barium nitrate and titanium dioxide precursors. The structural and morphological studies of the NPs were carried out by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The XRD pattern confirmed the formation of the BaTiO 3 NPs having an average size less than 100 nm. BaTiO 3 NPs were also evaluated for their efficacy against the human pathogenic bacteria. Significant antimicrobial and antibiofilm activities of BaTiO 3 NPs were observed against P. aeruginosa and S. aureus clinical isolates. Results presented in this work confirm that BaTiO 3 NPs can control the growth of biofilm formation activities of pathogenic bacteria at very low concentration and hence suggests their use as alternative antimicrobial agents. This is the first report on chemical method synthesized BaTiO 3 NPs for its biofilm inhibition activity. [ABSTRACT FROM AUTHOR]

Abstract Nanotechnology is a potential area that revolutionizes almost every sector of life and is predicted to become a major economic force in the near future. Recently, nanomaterials have received great attention for their properties at nanoscale regime and their applications in many areas primarily, agriculture and food sectors. The Nanomaterials are dispersed or solid particles, with a size range of 1–100 nm. In recent times, there has been an increased research work in this area to synthesize nanomaterials using various approaches. The use of natural biomolecules using 'green' approach play key role in the synthesis of nanomaterials having different shapes and sizes. Further this 'green synthesis' approach not only minimize the cost but also limit the need of hazardous chemicals and stimulates synthesis of greener, safe and environmentally friendly nanoparticles. The present review focus on studies based on the biosynthesis of nanoparticles using biomolecules such as plants, bacteria, fungi, etc. The text summarizes the recent work done globally by renowned researchers in area of biosynthesis of nanomaterials. It also discusses the potential applications of biologically mediated nanomaterials in the areas of agriculture and food and a critical evaluation of challenges within this field. Highlights • Biological nanomaterials received great attention for their properties at nanoscale regime and their applications in agriculture and food sectors. • The review imbibes the studies on the biosynthesis of nanoparticles using biomolecules such as plants, bacteria, fungi, etc. • It also discusses the potential applications of biologically mediated nanomaterials. [ABSTRACT FROM AUTHOR]

Yellow pepper extract and quercetin (QDH) were used for YPE-AgNPs and Q-AgNPs fabrication. The AgNPs were thoroughly characterized using standard physico-chemical techniques and were found monodispersed, pleomorphic and had variable shape and size with a lattice fringe of 0.23 nm. YPE-AgNPs and Q-AgNPs revealed a characteristic SPR band at 438 nm and 431 nm. The XRD crystal size of YPE-AgNPs and Q-AgNPs was 10.16 and 12.20 nm while TEM analysis showed a size range of 5–40 and 1–25 nm. Bio-fabricated AgNPs remained stable for at least four weeks as the SPR did not deviate with time. FTIR data revealed functionalization of AgNPs by organics of reaction mixture. AgNPs had robust antibacterial and antibiofilm activity against ESβL(+) Escherichia coli , Pseudomonas aeruginosa , and methicillin sensitive and resistant Staphylococcus aureus . Staining of isolates with fluorescent probes displayed the increased production of ROS and membrane permeability. AgNPs hampered EPS production, endorsed DNA leakage, and generated superoxide radicals. Time and concentration dependent experiments demonstrated a consistent decrease in bacterial growth. Structural changes viz. irregular margins, distortion, depressions/indentations and shrinkage of cells were obvious under SEM. AgNPs due to strong antibacterial activity could be exploited as a supplement with antibacterial drugs to control resilient human infections. [ABSTRACT FROM AUTHOR]

Pendimethalin (PM) is a dinitroaniline herbicide extensively applied against the annual grasses and broad-leaved weeds. There is no report available on PM-induced low-dose genotoxicity in human primary cells and in vivo test models. Such data gap has prompted us to evaluate the genotoxic potential of PM in human lymphocytes and rats. PM selectively binds in the minor groove of DNA by forming covalent bonds with G and C nitrogenous bases, as well as with the ribose sugar. PM induces micronucleus formation (MN) in human lymphocytes, indicating its clastogenic potential. Comet assay data showed 35.6-fold greater DNA damage in PM (200 μM)-treated human lymphocytes. Rat bone-marrow cells, at the highest dose of 50 mg/kg b w/day of PM also exhibited 10.5-fold greater DNA damage. PM at 200 μM and 50 mg/kg b w/day induces 193.4 and 229% higher reactive oxygen species generation in human lymphocytes and rat bone-marrow cells. PM-treated human lymphocytes and rat bone-marrow cells both showed dysfunction of mitochondrial membrane potential (ΔΨm). PM exposure results in the appearance of 72.2 and 35.2% sub-G1 apoptotic peaks in human lymphocytes and rat bone-marrow cells when treated with 200 μM and 50 mg/kg b w/day of PM. Rats exposed to PM also showed imbalance in antioxidant enzymes and histological pathology. Overall, our data demonstrated the genotoxic and apoptotic potentials of PM in human and animal test models. [ABSTRACT FROM AUTHOR]

Abstract: Brucellosis a zoonotic disease is endemic in Saudi Arabia especially in the Najed region due to the customary consumption of raw milk. For a detailed investigation of brucellosis in camel milk, 80 samples were collected from Riyadh region. Twenty‐four and sixteen percentage of the samples were positive for Brucella when tested with Rose Bengal test and ELISA, respectively. Genomic DNA from the milk samples was prepared using a modified method presented in this study. Brucella was detected in camel milk using three different primer sets targeting Brucella 16S rRNA gene, omp2, and IS711 genes. Among the three primer sets, an F4/R2 set of primers targeting Brucella 16S rRNA gene was most sensitive and yielded PCR products from nine milk samples. Finally, the 16S rRNA gene sequences of these isolates confirmed the contamination of Brucella spp. in nine milk samples. This study, therefore, suggests a high incidence of Brucella in camels of Riyadh. Practical applications: This manuscript describes a modified method for the isolation of DNA from camel milk. The DNA was subsequently used successfully for the amplification of various genes for detecting Brucella. Furthermore, there was no report from Riyadh region on the detection of Brucella from camel milk. This report, therefore, points out toward an important health issue associated with consumption of raw camel milk. If published, this report will be helpful in educating the local population about the health risk associated with the consumption of raw milk. [ABSTRACT FROM AUTHOR]

The unique properties of nickel oxide nanoparticles (NiO-NPs) distinguish it from traditional nickel containing materials, and enable its industrial application as an advanced nanomaterial. Despite the benefits, the in vivo toxicological studies on NiO-NPs have been mainly focused on its pulmonary pathology. However, NiO-NPs exposure via oral route and its subsequent toxic effects in exposed animals are still lacking. Hence, we evaluated the NiO-NPs oral toxicity in male Wistar rats. NiO-NPs induced significant increase in chromosomal aberrations (CAs), micronuclei (MN) formation and, DNA damage in rats. Flow cytometric analysis showed apoptosis, ROS generation and dysfunction of mitochondrial membrane potential ( ΔΨm ). Imbalance of antioxidant enzymes, along with histological alterations was found in liver. Taking together, these results unequivocally suggested that NiO-NPs induced toxicity was through cyto-genetic alterations, oxidative stress, apoptosis and liver toxicity. The western blotting data validated the interplay of p53 and MAPKAPK-2 signalling via activation of caspases 8, 3, cyto c, pro-apoptotic bax and anti-apoptotic bcl-2 proteins. [ABSTRACT FROM AUTHOR]

Brucellosis is an endemic zoonotic disease in worldwide, particularly prevalent in Central Najed region of Saudi Arabia, where the population has a nomadic heritage of drinking fresh milk from goats, sheep and camels. The present study aims to develop a simple antibody-functionalized nanomaterial-based biosensor for the detection of Brucella in milk samples. The detection of Brucella by the proposed sensor is based on measuring changes in electrical signals and study their properties. The zinc oxide nano particles (ZnO-NPs) were synthesized through solution process in liquid medium at reduced refluxing temperature. The crystalline properties of obtained ZnO-NPs were analyzed via X-ray diffraction pattern (XRD), whereas the morphology was observed with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The investigation reveals that obtained NPs were almost spherical in shape with an average diameter of ∼10–15 nm. The binding of the anti- Brucella antibody to ZnO-NPs was verified by FTIR. Our study showed that the anti- Brucella antibody was successfully functionalized on ZnO-NPs and these functionalized NPs were also effectively deposited on aluminum sheets (Al-sheet). Finally, Al-sheets developed above were used as an electrode component for voltametric detection via cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

Brucellosis is endemic worldwide due to the nomadic heritage of drinking fresh milk from goats, sheeps and camels. This study aims at developing an antibody based sensor for the detection of Brucella , wherein the binding of Brucella to the sensor will be detected by measuring the changes in electrical signals via cyclic voltammetric properties. The morphology of the used MWCNTs was observed under SEM, FESEM, and TEM. The MWCNTs (ropes like structure) used for the development of sensor were 2–4 μm in length and ∼10–15 nm in diameter as observed under SEM, FESEM, and TEM. MWCNTs were functionalized via acid treatment/oxidation process and the functional behavior of molecules was confirmed with FTIR spectroscopy. Antibodies were conjugated onto the functionalized MWCNTs using classical EDC coupling reactions. When observed under SEM, binding of Brucella abortus to these anti- Brucella antibody functionalized MWCNTs was clearly observed. Finally, these antibody functionalized MWCNTs were deposited on aluminum sheets for the voltammetric detection of Brucella . Results indicate that the antibody functionalized MWCNTs prepared in this study can be used successfully for the detection of Brucella . [ABSTRACT FROM AUTHOR]

The present investigation was aimed to discover the activity of raw (RCNTs) and functionalized multi-walled carbon nanotubes (FCNTs) for their cytotoxic potential in human breast cancer (MCF-7) cells. The RCNTs were functionalized with the acid treatment method and were characterized by SEM and TEM. The morphology of RCNTs and FCNTs were found to be variable with a size range of ∼10–15 nm diameter were as the length goes up to 2–4 μm. For, cytotoxicity assessments, MCF-7 cells were exposed to RCNTs and FCNTs at 5–400 μg/ml concentrations for 24 h. The cytotoxicity was measured by MTT and NRU assays, and cellular morphology using phase contrast microscope. Further, intracellular reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) were also studied. The results of MTT and NRU assays exhibited a concentration-dependent decrease in cell viability of MCF-7 cells. The RCNTs and FCNTs exposed cells were also found to alter the normal morphology of MCF-7 cells. Furthermore, the cells showed significant induction in ROS generation and reduction in MMP level. The results of this study, demonstrated that RCNTs and FCNTs has the potential to induce cytotoxicity in MCF-7 cells which could be mediated through the reactive oxygen species (ROS) generation. [ABSTRACT FROM AUTHOR]

Nanotechnology based therapeutics has emerged as a promising approach for augmenting the activity of existing antimicrobials due to the unique physical and chemical properties of nanoparticles (NPs). Nickel oxide nanoparticles (NiO-NPs) have been suggested as prospective antibacterial and antitumor agent. In this study, NiO-NPs have been synthesized by a green approach using Eucalyptus globulus leaf extract and assessed for their bactericidal activity. The morphology and purity of synthesized NiO-NPs determined through various spectroscopic techniques like UV-Visible, FT-IR, XRD, EDX and electron microscopy differed considerably. The synthesized NiO-NPs were pleomorphic varying in size between 10 and 20 nm. The XRD analysis revealed the average size of NiO-NPs as 19 nm. The UV-Vis spectroscopic data showed a strong SPR of NiO-NPs with a characteristic spectral peak at 396 nm. The FTIR data revealed various functional moieties like C=C, C–N, C–H and O–H which elucidate the role of leaf biomolecules in capping and dispersal of NiO-NPs. The bioactivity assay revealed the antibacterial and anti-biofilm activity of NiO-NPs against ESβL (+) E. coli , P. aeruginosa , methicillin sensitive and resistant S. aureus . Growth inhibition assay demonstrated time and NiO-NPs concentration dependent decrease in the viability of treated cells. NiO-NPs induced biofilm inhibition was revealed by a sharp increase in characteristic red fluorescence of PI, while SEM images of NiO-NPs treated cells were irregular shrink and distorted with obvious depressions/indentations. The results suggested significant antibacterial and antibiofilm activity of NiO-NPs which may play an important role in the management of infectious diseases affecting human health. [ABSTRACT FROM AUTHOR]

Organic compounds from plants are an attractive alternative to conventional antimicrobial agents. Therefore, two compounds namely M-1 and M-2 were purified from Origanum vulgare L. and were identified as carvacrol and thymol, respectively. Antimicrobial and antibiofilm activities of these compounds along with chlorhexidine digluconate using various assays was determined against dental caries causing bacteria Streptococcus mutans. The IC values of carvacrol (M-1) and thymol (M-2) against S. mutans were 65 and 54 µg/ml, respectively. Live and dead staining and the MTT assays reveal that a concentration of 100 µg/ml of these compounds reduced the viability and the metabolic activity of S. mutans by more than 50%. Biofilm formation on the surface of polystyrene plates was significantly reduced by M-1 and M-2 at 100 µg/ml as observed under scanning electron microscope and by colorimetric assay. These results were in agreement with RT-PCR studies. Wherein exposure to 25 µg/ml of M-1 and M-2 showed a 2.2 and 2.4-fold increase in Autolysin gene ( AtlE) expression level, respectively. While an increase of 1.3 and 1.4 fold was observed in the super oxide dismutase gene ( sodA) activity with the same concentrations of M-1 and M-2, respectively. An increase in the ymcA gene and a decrease in the gtfB gene expression levels was observed following the treatment with M-1 and M-2. These results strongly suggest that carvacrol and thymol isolated from O. vulgare L. exhibit good bactericidal and antibiofilm activity against S. mutans and can be used as a green alternative to control dental caries. [ABSTRACT FROM AUTHOR]

We have studied the genotoxic and apoptotic potential of ferric oxide nanoparticles (Fe 2 O 3 -NPs) in Raphanus sativus (radish). Fe 2 O 3 -NPs retarded the root length and seed germination in radish. Ultrathin sections of treated roots showed subcellular localization of Fe 2 O 3 -NPs, along with the appearance of damaged mitochondria and excessive vacuolization. Flow cytometric analysis of Fe 2 O 3 -NPs (1.0 mg/mL) treated groups exhibited 219.5%, 161%, 120.4% and 161.4% increase in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), nitric oxide (NO) and Ca 2+ influx in radish protoplasts. A concentration dependent increase in the antioxidative enzymes glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (LPO) has been recorded. Comet assay showed a concentration dependent increase in deoxyribonucleic acid (DNA) strand breaks in Fe 2 O 3 -NPs treated groups. Cell cycle analysis revealed 88.4% of cells in sub-G1 apoptotic phase, suggesting cell death in Fe 2 O 3 -NPs (2.0 mg/mL) treated group. Taking together, the genotoxicity induced by Fe 2 O 3 -NPs highlights the importance of environmental risk associated with improper disposal of nanoparticles (NPs) and radish can serve as a good indicator for measuring the phytotoxicity of NPs grown in NP-polluted environment. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the protective effects of Portulaca oleracea seed extract (POA) against cytotoxicity, oxidative stress and reactive oxygen species (ROS) generation induced by hydrogen peroxide (H2O2) in human liver cells (HepG2). Methods: The extract (POA) was obtained by ethanol extraction of P. oleracea seeds. Cytotoxicity in HepG2 cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, neutral red uptake (NRU) assay and morphological changes. The cells were pre-exposed to noncytotoxic concentrations (5 - 25 μg/mL) of POA for 24 h, and then cytotoxic (0.25 mM) concentration of H2O2. After 24 h of exposure, MTT and NRU assays were used to evaluate cell viability, while morphological changes were assessed using phase contrast inverted microscopy. The effect of POA on reduced glutathione (GSH) level, lipid peroxidation (LPO), and ROS generation induced by H2O2 was also studied. Results: The results showed that pre-exposure to POA (25 μg/mL) significantly (p <0.01) attenuated the loss of cell viability by up to 38 % against H2O2-induced oxidative stress and ROS generation. In addition, POA (25 μg/mL) significantly (p <0.01) increased GSH level (31 %), but decreased the levels of LPO (37 %) and ROS generation (49 %). Conclusion: This study demonstrates that POA has the capacity to protect HepG2 cells against H2O2- induced cell death by inhibiting oxidative stress and ROS generation. [ABSTRACT FROM AUTHOR]

We have synthesized two new complexes of platinum ( 1 ) and ruthenium ( 2 ) with α-amino acid, l -alanine, and 2,3-dihydroxybenzaldehyde derived Schiff base ( L ). The ligand and both complexes were characterized by using elemental analysis and several other spectroscopic techniques viz; IR, 1 H, 13 C NMR, EPR, and ESI-MS. Furthermore, the protein-binding ability of synthesized complexes was monitored by UV–visible, fluorescence and circular dichroism techniques with a model protein, human serum albumin (HSA). Both the PtL 2 and RuL 2 complexes displayed significant binding towards HSA. Also, in vitro cytotoxicity assay for both complexes was carried out on human hepatocellular carcinoma cancer (HepG2) cell line. The results showed concentration-dependent inhibition of cell viability. Moreover, the generation of reactive oxygen species was also evaluated, and results exhibited substantial role in cytotoxicity. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles (ZnONPs) were synthesised through a simple and efficient biogenic synthesis approach, exploiting the reducing and capping potential of Aloe barbadensis Miller ( A. vera ) leaf extract (ALE). ALE-capped ZnO nanoparticles (ALE-ZnONPs) were characterized using UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) analyses. XRD analysis provided the average size of ZnONPs as 15 nm. FTIR spectral analysis suggested the role of phenolic compounds, terpenoids and proteins present in ALE, in nucleation and stability of ZnONPs. Flow cytometry and atomic absorption spectrophotometry (AAS) data analyses revealed the surface binding and internalization of ZnONPs in Gram +ve ( Staphylococcus aureus ) and Gram −ve ( Escherichia coli ) cells, respectively. Significant antibacterial activity of ALE-ZnONPs was observed against extended spectrum beta lactamases (ESBL) positive E. coli , Pseudomonas aeruginosa , and methicillin resistant S. aureus (MRSA) clinical isolates exhibiting the MIC and MBC values of 2200, 2400 μg/ml and 2300, 2700 μg/ml, respectively. Substantial inhibitory effects of ALE-ZnONPs on bacterial growth kinetics, exopolysaccharides and biofilm formation, unequivocally suggested the antibiotic and anti-biofilm potential. Overall, the results elucidated a rapid, environmentally benign, cost-effective, and convenient method for ALE-ZnONPs synthesis, for possible applications as nanoantibiotics or drug carriers. [ABSTRACT FROM AUTHOR]

Streptococcus mitis from the oral cavity causes endocarditis and other systemic infections. Rising resistance against traditional antibiotics amongst oral bacteria further aggravates the problem. Therefore, antimicrobial and antibiofilm activities of zinc oxide and titanium dioxide nanoparticles (NPs) synthesized and characterized during this study against S. mitis ATCC 6249 and Ora-20 were evaluated in search of alternative antimicrobial agents. ZnO and TiO-NPs exhibited an average size of 35 and 13 nm, respectively. The IC values of ZnO and TiO-NPs against S. mitis ATCC 6249 were 37 and 77 µg ml, respectively, while the IC values against S. mitis Ora-20 isolate were 31 and 53 µg ml, respectively. Live and dead staining, biofilm formation on the surface of polystyrene plates, and extracellular polysaccharide production show the same pattern. Exposure to these nanoparticles also shows an increase (26-83 %) in super oxide dismutase (SOD) activity. Three genes, namely bapA1, sodA, and gtfB like genes from these bacteria were identified and sequenced for quantitative real-time PCR analysis. An increase in sodA gene (1.4- to 2.4-folds) levels and a decrease in gtfB gene (0.5- to 0.9-folds) levels in both bacteria following exposure to ZnO and TiO-NPs were observed. Results presented in this study verify that ZnO-NPs and TiO-NPs can control the growth and biofilm formation activities of these strains at very low concentration and hence can be used as alternative antimicrobial agents for oral hygiene. [ABSTRACT FROM AUTHOR]

We have evaluated the in vitro low dose hepatotoxic effects of two flame-retardants (BDE-47 and BDE-32) in HepG2 cells. Both congeners declined the viability of cells in MTT and NRU cell viability assays. Higher level of intracellular reactive oxygen species (ROS) and dysfunction of mitochondrial membrane potential (ΔΨ m ) were observed in the treated cells. Comet assay data confirmed the DNA damaging potential of both congeners. BDE-47 exposure results in the appearance of subG 1 apoptotic peak (30.1%) at 100 nM, while BDE-32 arrested the cells in G 2 /M phase. Among the set of 84 genes, BDE-47 induces downregulation of majority of mRNA transcripts, whilst BDE-32 showed differential expression of transcripts in HepG2. The ultrastructural analysis revealed mitochondrial swelling and degeneration of cristae in BDE-47 and BDE-32 treated cells. Overall our data demonstrated the hepatotoxic potential of both congeners via alteration of vital cellular pathways. [ABSTRACT FROM AUTHOR]

Background: Cancer is one of the major causes of death worldwide. The plant-derived natural products have received considerable attention in recent years due to their diverse pharmacological properties including anticancer effects. Nepeta deflersiana (ND) is used in the folk medicine as antiseptic, carminative, antimicrobial, antioxidant, and for treating rheumatic disorders. However, the anticancer activity of ND chloroform extract has not been explored so far. Objectives: The present study was aimed to investigate the anticancer activities of chloroform Nepeta deflersiana extract and various sub-fractions (ND-1–ND-15) of ND against human breast cancer cells (MCF-7) and human lung cancer cells (A-549). Materials and Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red uptake assays, and cellular morphological alterations using phase contrast light microscope were studied. Cells were exposed with 10–1000 μg/ml of sub-fractions of ND for 24 h. Results: Results showed that selected sub-fractions of the chloroform extract significantly reduced the cell viability of MCF-7 and A-549 cells, and altered the cellular morphology in a concentration-dependent manner. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity compared to other fractions whereas, ND-1 did not cause any cytotoxicity even at higher concentrations. The A-549 cells were found to be more sensitive to growth inhibition by all the extracts as compared to the MCF-7 cells. Conclusion: The present study provides preliminary screening of anticancer activities of chloroform extract and sub-fractions of ND, which can be further used for the development of a potential therapeutic anticancer agent. [ABSTRACT FROM AUTHOR]

Context: Garden cress [Lepidium sativum(Brassicaceae)] has been widely used to treat a number of ailments in traditional medicine. The pharmacological and preventive potential ofLepidium sativum, such as anti-inflammatory, antipyretic, antihypertensive, anti-ashthamatic, anticancer, and anti-oxidant, are well known. Objective: The present investigation was designed to study the protective effects of chloroform extract ofLepidium sativumseed (LSE) against oxidative stress and cytotoxicity induced by hydrogen peroxide (H2O2) in human liver cells (HepG2). Materials and methods: Cytotoxicity of LSE and H2O2was identified by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), neutral red uptake (NRU) assays, and morphological changes in HepG2. The cells were pre-exposed to biologically safe concentrations (5–25 μg/ml) of LSE for 24 h, and then cytotoxic (0.25 mM) concentration of H2O2was added. After 24 h of the exposures, cell viability by MTT, NRU assays, and morphological changes in HepG2 were evaluated. Further, protective effects of LSE on reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), lipid peroxidation (LPO), and reduced glutathione (GSH) levels induced by H2O2were studied. Results: Pre-exposure of LSE significantly attenuated the loss of cell viability up to 48% at 25 µg/ml concentration against H2O2(LD50value = 2.5 mM). Results also showed that LSE at 25 µg/ml concentration significantly inhibited the induction of ROS generation (45%) and LPO (56%), and increases the MMP (55%) and GSH levels (46%). Discussion and conclusion: The study suggests the cytoprotective effects of LSE against H2O2-induced toxicity in HepG2. The results also demonstrate the anti-oxidative nature of LSE. [ABSTRACT FROM PUBLISHER]

Background: Cancer is one of the major causes of death worldwide. The plant-derived natural products have received considerable attention in recent years due to their diverse pharmacological properties including anticancer effects. Nepeta deflersiana (ND) is used in the folk medicine as antiseptic, carminative, antimicrobial, antioxidant, and for treating rheumatic disorders. However, the anticancer activity of ND chloroform extract has not been explored so far. Objectives: The present study was aimed to investigate the anticancer activities of chloroform Nepeta deflersiana extract and various sub-fractions (ND-1-ND-15) of ND against human breast cancer cells (MCF-7) and human lung cancer cells (A-549). Materials and Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and neutral red uptake assays, and cellular morphological alterations using phase contrast light microscope were studied. Cells were exposed with 10-1000 μg/ml of sub-fractions of ND for 24 h. Results: Results showed that selected sub-fractions of the chloroform extract significantly reduced the cell viability of MCF-7 and A-549 cells, and altered the cellular morphology in a concentration-dependent manner. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity compared to other fractions whereas, ND-1 did not cause any cytotoxicity even at higher concentrations. The A-549 cells were found to be more sensitive to growth inhibition by all the extracts as compared to the MCF-7 cells. Conclusion: The present study provides preliminary screening of anticancer activities of chloroform extract and sub-fractions of ND, which can be further used for the development of a potential therapeutic anticancer agent. [ABSTRACT FROM AUTHOR]

The present investigations were carried out to study the protective potential of four extracts (namely petroleum ether extract (LCR), chloroform extract (LCM), ethyl acetate extract (LCE), and alcoholic extract (LCL)) of Lavandula coronopifolia on oxidative stress-mediated cell death induced by ethanol, a known hepatotoxin in human hapatocellular carcinoma (HepG2) cells. Cells were pretreated with LCR, LCM, LCE, and LCL extracts (10–50 μg/ml) of L. coronopifolia for 24 h and then ethanol was added and incubated further for 24 h. After the exposure, cell viability using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red uptake assays and morphological changes in HepG2 cells were studied. Pretreatment with various extracts of L. coronpifolia was found to be significantly effective in countering the cytotoxic responses of ethanol. Antioxidant properties of these L. coronopifolia extracts against reactive oxygen species (ROS) generation, lipid peroxidation (LPO), and glutathione (GSH) levels induced by ethanol were investigated. Results show that pretreatment with these extracts for 24 h significantly inhibited ROS generation and LPO induced and increased the GSH levels reduced by ethanol. The data from the study suggests that LCR, LCM, LCE, and LCL extracts of L. coronopifolia showed hepatoprotective activity against ethanol-induced damage in HepG2 cells. However, a comparative study revealed that the LCE extract was found to be the most effective and LCL the least effective. The hepatoprotective effects observed in the study could be associated with the antioxidant properties of these extracts of L. coronopifolia. [ABSTRACT FROM AUTHOR]

Rhamnolipids extracted from Pseudomonas aeruginosa strain JS-11 were utilized for synthesis of stable silver nanoparticles (Rh-AgNPs). The Rh-AgNPs (23 nm) were characterized by Fourier transform infra-red (FTIR) spectroscopy, atomic force microscopy (AFM) and transmission electron microscopy (TEM). The cytotoxicity assays suggested significant decrease in viability of Rh-AgNPs treated human breast adenocarcinoma (MCF-7) cells, compared with normal human peripheral blood mononuclear (PBMN) cells. Flow cytometry data revealed 1.25-fold ( p < 0.05) increase in the fluorescence of 2′,7′-dichlorofluorescein (DCF) at 0.25 μg/mL. However, at Rh-AgNPs concentrations of 0.5 and 1.0 μg/mL, much lesser fluorescence was noticed, which is attributed to cell death. Results with the fluorescent probe Rh123 demonstrated change in inner mitochondrial membrane and dissipation of membrane potential. The cell cycle analysis suggested 19.9% ( p < 0.05) increase in sub-G1 peak with concomitant reduction in G1 phase at 1 μg/mL of Rh-AgNPs, compared to 2.7% in untreated control. The real-time RT 2 Profiler™ PCR array data elucidated the overexpression of seven oxidative stress and DNA damage pathways genes viz. BAX, BCl 2 , Cyclin D1, DNAJA1, E2F transcription factor 1, GPX1 and HSPA4, associated with apoptosis signaling, proliferation and carcinogenesis, pro inflammatory and heat shock responses in Rh-AgNPs treated cells. Thus, the increased ROS production, mitochondrial damage and appearance of sub-G1 (apoptotic) population suggested the anti-proliferative activity, and role of oxidative stress pathway genes in Rh-AgNPs induced death of MCF-7 cancer cells. [ABSTRACT FROM AUTHOR]

A simple and rapid microwave assisted method of green synthesis of silver nanoparticles (AgNPs) was developed using aqueous leaf extract of Eucalyptus globulus(ELE), and their antibacterial and antibiofilm potential investigated. With this aim, the aqueous solutions of ELE and AgNO3(1 mM) were mixed (1:4 v/v), and microwave irradiated at 2450 Mhz, for 30 sec. The instant color change of the ELE-AgNO3 mixture from pale yellow to dark brown indicated ELE-AgNPs synthesis. The intensity of peak at 428 nm in UV-Vis spectra, due to the surface plasmon resonance of AgNPs, varied with the amount of ELE, AgNO3 concentration, pH and time of incubation. The biosynthesized ELE-AgNPs were characterized by UV-visible spectroscopy, XRD, TEM, SEM-EDX, FTIR and TGA analyses. The size of ELE-AgNPs was determined to be in range of 1.9–4.3 nm and 5-25 nm, with and without microwave treatment, respectively. SEM exhibited the capping of AgNPs with the ELE constituents, and validated by FTIR analysis. The FTIR data revealed the presence of plant organic constituents and metabolites bound to ELE-AgNPs, which contributes for their stability. The antimicrobial activity of ELE-AgNPs was assessed by growth and biofilm inhibition of extended spectrum β-lactamase (ESBL) producing Pseudomonas aeruginosa, Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) clinical bacterial isolates. The results demonstrated that S. aureus were more sensitive to ELE-AgNPs than E. coli and P. aeruginosa. MRSA exhibited higher sensitive than MSSA, whereas P. aeruginosa were more sensitive than E. coli to ELE-AgNPs treatment. Also, significant (83 ± 3% and 84 ± 5%) biofilm inhibition was observed in case of S. aureus and P. aeruginosa, respectively. The results elucidated environmentally friendly, economical and quick method for production of colloidal bio-functionalized ELE-AgNPs, for effectual clinical applications, as broad spectrum antibacterial agents and biofilm inhibitors. [ABSTRACT FROM AUTHOR]

In this work, we report a series of benzimidazole derivatives synthesized from benzene-1,2-diamine and aryl-aldehydes at room temperature. The synthesized compounds have been characterized on the basis of elemental analysis and various spectroscopic studies viz., IR, 1 H- and 13 C-NMR, ESI-MS as well by X-ray single X-ray crystallographic study. Interaction of these compounds with CT-DNA has been examined with fluorescence experiments and showed significant binding ability. All the synthesized compounds have been screened for their antitumor activities against various human cancer cell lines viz., Human breast adenocarcinoma cell line (MCF-7), Human leukemia cell line (THP-1), Human prostate cancer cell lines (PC-3) and adenocarcinomic human alveolar basal epithelial cell lines (A-549). Interestingly, all the compounds showed significant anticancer activity. [ABSTRACT FROM AUTHOR]

Owing to the pharmacological potential of ATRA (all trans-retinoic acid), a series of retinamides and a 1-(retinoyl)-1,3-dicyclohexylurea compound were prepared by reacting ATRA with long chain alkyl or alkenyl fatty amines by using a 4-demethylaminopyridine (DMAP)-catalyzed N,N'-dicyclohexylcarbodiimide (DCC) coupling. The successful synthesis of the target compounds was demonstrated using a range of spectroscopic techniques. The cytotoxicity of the compounds was measured along with their ability to induce cell cycle arrest and apoptosis in human cancer cell lines MCF-7 (breast cancer) and HepG2 (liver cancer) and normal human cell line HEK293 (embryonic kidney). The results of cytotoxicity and flow cytometry data showed that the compounds had a moderate to strong effect against MCF-7 and HepG2 cells and were less toxic to HEK293 cells. N-oleyl-retinamide was found to be the most potent anticancer agent and was more effective against MCF-7 cells than HepG2 cells. [ABSTRACT FROM AUTHOR]

A soft chemical solution process was used in synthesis of photocatalytic zinc oxide nanoparticles (ZnO-PNPs) at low temperature. The synthesized PNPs were characterized in terms of their crystallinity, morphological, catalytic, spectroscopic and statistical analysis techniques. X-ray powder diffraction patterns (XRD) were used to know the crystalline property of the prepared materials whereas field emission electronic microscopy (FESEM) was employed to observe the morphology of grown NPs. UV–visible spectroscopy was employed to analyze the absorbance of degraded safranine (SA) dye in presence of NPs at desired time interval. Parameters of statistical analysis give necessary information for established analytical procedures to ensure quality and purity of results. With the help of this analytical method, outcomes were calculated in terms of absorbance such as standard deviation (SD), relative standard deviation (RSD), etc. at 95% confidence level. The photocatalytic deactivation/degradation process significantly enhanced the activity of ZnO-PNPs under UV–visible light in presence of SA dye. The effective concentration of used PNPs was optimized and validated via standard analytical procedure, which exhibited greater significance on deactivation process. The absorption spectra of photocatalyzed solution and activity of ZnO-PNPs were compared with those of pure ZnO, obtained by UV–visible spectroscopy. [ABSTRACT FROM AUTHOR]

The high prevalence of extended-spectrum β-lactamases (76.3 %) and metallo-β-lactamases (7.3 %) amongst the bacteria Pseudomonas aeruginosa is a critical problem that has set forth an enormous therapeutic challenge. The suggested role of nanoparticles as next generation antibiotics, and inadequate information on antibacterial activity of aluminium oxide nanoparticles has led us to investigate the green synthesis of aluminium oxide nanoparticles (AlO NPs) using leaf extracts of lemongrass and its antibacterial activity against extended-spectrum β-lactamases and metallo-β-lactamases clinical isolates of P. aeruginosa. The synthesized AlO-NPs were characterized by scanning electron microcopy, high resolution-transmission electron microscopy, atomic force microscopy, X-ray diffraction, Zeta potential, and differential light scattering techniques. The X-ray diffraction data revealed the average size of the spherical AlO-NPs as 34.5 nm. The hydrodynamic size in Milli Q water and Zeta potential were determined to be 254 nm and +52.2 mV, respectively. The minimal inhibitory concentration of AlO-NPs was found to be in the range of 1,600-3,200 µg/ml. Treatment at concentrations >2,000 µg/ml, resulted in complete growth inhibition of extended-spectrum β-lactamases and metallo-β-lactamases isolates. Scanning electron microcopy analysis revealed the clusters of nanoparticles attached to the bacterial cell surface, causing structural deformities in treated cells. High resolution-transmission electron microscopy analysis confirmed that nanoparticles crossed the cell membrane to become intracellular. The interaction of nanoparticles with the cell membrane eventually triggered the loss of membrane integrity, most likely due to intracellular oxidative stress. The data explicitly suggested that the synthesized AlO-NPs can be exploited as an effective bactericidal agent against extended-spectrum β-lactamases, non-extended-spectrum β-lactamases and metallo-β-lactamases strains of P. aeruginosa, regardless of their drug resistance patterns and mechanisms. The results elucidated the clinical significance of AlO-NPs in developing an effective antibacterial therapeutic regimen against the multi-drug resistant bacterial infections. The use of leaf extract of lemongrass for the synthesis of AlO-NPs appears to be cost effective, nontoxic, eco-friendly and its strong antibacterial activity against multi-drug resistant strains of P. aeruginosa offers compatibility for pharmaceutical and other biomedical applications. [ABSTRACT FROM AUTHOR]

The present investigation was aimed to study the cytotoxicity, oxidative stress, and genotoxicity induced by molybdenum nanoparticles (Mo-NPs) in mouse skin fibroblast cells (L929). Cells were exposed to different concentrations (1–100 μg/ml) of Mo-NPs (size 40 nm) for 24 and 48 h. After the exposure, different cytotoxicity assays (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide, MTT; neutral red uptake, NRU; and cellular morphology) and oxidative stress markers (lipid peroxidation, LPO; glutathione, GSH; and catalase) were studied. Further, Mo-NPs-induced intracellular reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest, and DNA damage were also studied. L929 cells treated with Mo-NPs showed a concentration- and time-dependent decrease in cell viability and a loss of the normal cell morphology. The percentage cell viability was recorded as 25%, 42%, and 58% by MTT assay and 24%, 46%, and 56% by NRU assay at 25, 50, and 100 μg/ml of Mo-NPs, respectively after 48 h exposure. Furthermore, the cells showed a significant induction of oxidative stress. This was confirmed by the increase in LPO and ROS generation, as well as the decrease in the GSH and catalase levels. The decrease in MMP also confirms the impaired mitochondrial membrane. The cell cycle analysis and comet assay data revealed that Mo-NPs induced G2/M arrest and DNA damage in a concentration-dependent manner. Our results demonstrated, for the first time, Mo-NPs induced cytotoxicity, oxidative stress and genotoxicity in L929 cells. Thus, data suggest the potential hazardous nature of Mo-NPs. [ABSTRACT FROM AUTHOR]

The formation of bacterial biofilm is a major challenge in clinical applications. The main aim of this study is to describe the synthesis, characterization and biocidal potential of zinc oxide nanoparticles (NPs) against bacterial strain Pseudomonas aeruginosa. These nanoparticles were synthesized via soft chemical solution process in a very short time and their structural properties have been investigated in detail by using X-ray diffraction and transmission electron microscopy measurements. In this work, the potential of synthesized ZnO-NPs (∼10–15 nm) has been assessed in-vitro inhibition of bacteria and the formation of their biofilms was observed using the tissue culture plate assays. The crystal violet staining on biofilm formation and its optical density revealed the effect on biofilm inhibition. The NPs at a concentration of 100 µg/mL significantly inhibited the growth of bacteria and biofilm formation. The biofilm inhibition by ZnO-NPs was also confirmed via bio-transmission electron microscopy (Bio-TEM). The Bio-TEM analysis of ZnO-NPs treated bacteria confirmed the deformation and damage of cells. The bacterial growth in presence of NPs concluded the bactericidal ability of NPs in a concentration dependent manner. It has been speculated that the antibacterial activity of NPs as a surface coating material, could be a feasible approach for controlling the pathogens. Additionally, the obtained bacterial solution data is also in agreement with the results from statistical analytical methods. [ABSTRACT FROM AUTHOR]