Search

We investigate the ultrafast transient absorption spectrum of Bi2Se3 topological insulator. Bi2Se3 single crystal is grown through conventional solid-state reaction routevia self-flux method. The structural properties have been studied in terms of high-resolution Powder X-ray Diffraction (PXRD). Detailed Rietveld analysis of PXRD of the crystal showed that sample is crystallized in the rhombohedral crystal structure with a space group of R-3m, and the lattice parameters are a=b=4.14A and c=28.7010A. Scanning Electron Microscopy (SEM) result shows perfectly crystalline structure with layered type morphology which evidenced from surface XRD. Energy Dispersive Spectroscopy (EDS) analysis determined quantitative amounts of the constituent atoms, found to be very close to their stoichiometric ratio. Further the fluence dependent nonlinear behaviour is studied by means of ultrafast transient absorption spectroscopy. The ultrafast spectroscopy also predicts the capability of this single crystal to generate Terahertz (THz) radiations (T-rays)., 4 Pages Text + Figs Accepted AIP Proceedings

Increasing society awareness on sustainable development and environmental pollution has led to increase in utilization of industry-based secondary fibers such as old newsprint, mixed office waste, and old magazines for paper making. Paper recycling is necessary to reduce dependency on virgin wood pulp and to avoid disposal problem for waste paper. Deinking, the most important process in waste paper recycling, is traditionally handled by large quantities of chemicals, is expensive, and is damaging the environment. Microbial enzymes offer a better alternative for eco-friendly deinking of waste paper by reducing chemical consumption, which leads to cost-cutting, energy saving, and lower waste production. This chapter describes microbial enzymes reported for waste paper recycling and comparison of enzymatic deinking with other conventional methods.

Quorum sensing (QS) and signal molecules used for interspecies communication are well defined in mesophiles, but there is still a plethora of microorganisms in which existence and mechanisms of QS need to be explored, thermophiles being among them. In silico analysis has revealed the presence of autoinducer-2 (AI-2) class of QS signaling molecules in thermophiles, synthesized by LuxS (AI-2 synthase), though the functions of this system are not known. In this study, LuxS of Meiothermus ruber was used for understanding the mechanism and functions of AI-2 based QS among thermophilic bacteria. The luxS gene of M. ruber was expressed in luxS- deletion mutant of Escherichia coli. Complementation of luxS resulted in significant AI-2 activity, enhanced biofilm formation, and antibiotic susceptibility. Transcriptome analysis showed significant differential expression of 204 genes between the luxS-complemented and luxS- deletion mutant of E. coli. Majority of the genes regulated by luxS belonged to efflux pumps. This elucidation may contribute towards finding novel alternatives against incessant antibiotic resistance in bacteria.Key Points• Expression of luxS in luxS-E. coli resulted in increase in biofilm index. • Reduction in the MIC of antibiotics was observed after complementation of luxS. • Downregulation of efflux pump genes was observed after complementation of luxS. • Transcriptome analysis showed that 204 genes were differentially regulated significantly.

In the present article, we report a comprehensive study of structural and physical properties of binary alloy Sn1-xSbx (x = 0.4, 0.5, 0.6). All the alloys are grown through the self-flux method under well-optimized heat treatment. The as-grown crystals are structurally characterized through Powder X-Ray Diffraction (PXRD), Scanning Electron Microscope (SEM), and Energy Dispersive X-Ray Analysis (EDAX). Simultaneously, the X-Ray Photoelectron Spectroscopy (XPS) is used to probe the surface of the crystals. All the crystals crystallize in rhombohedral structure with the R −3 m space group, as confirmed from Rietveld refined PXRD pattern. Sn1-xSbx is found to have a secondary phase with an elongated unit cell in conjunction with the primary phase for a specific alloy of x = 0.6. These binary systems are considered to be a possible candidate of topological superconductivity as they show the opening of bands near Fermi level with the inclusion of Spin-Orbit Coupling (SOC) protocols in DFT calculations. However, the superconductivity in all samples is confirmed through DC magnetization measurements under Field Cooled (FC) and Zero Field Cooled (ZFC) measurement at 10 Oe magnetic field. The nature of observed superconductivity is determined by isothermal magnetization (M-H) measurements at 2K, in which these binary alloys are proved to be type-II superconductors.

Acinetobacter baumannii, a leading cause of nosocomial infections, is a serious health threat. Limited therapeutic options due to multi-drug resistance and tolerance due to persister cells have urged the scientific community to develop new strategies to combat infections caused by this pathogen effectively. Since combination antibiotic therapy is an attractive strategy, the effect of combinations of antibiotics, belonging to four classes, was investigated on eradication of persister cells in A. baumannii. Among the antibiotics included in the study, tobramycin-based combinations were found to be the most effective. Tobramycin, in combination with colistin or ciprofloxacin, eradicated persister cells in A. baumannii in late exponential and stationary phases of growth. Mechanistically, colistin facilitated the entry of tobramycin into cells by increasing membrane permeability and inducing hyperpolarization of the inner membrane accompanied by increase in ROS production. Expression of the genes encoding universal stress protein and efflux pumps was down-regulated in response to tobramycin and colistin, suggesting increased lethality of their combination that might be responsible for eradication of persister cells. Thus, a combination of tobramycin and colistin could be explored as a promising option for preventing the relapse of A. baumannii infections due to persister cells.

The present paper deals with the simulation of impact of ogival tip projectile on multi-layered plain woven high modulus polypropylene (HMPP) fabric impregnated with shear-thickening fluids (STFs) composed of fumed silica nanoparticles suspended in polyethylene glycol (PEG) using finite element analysis as implemented in LS-DYNA. The effect of STF impregnation on fabric are taken into account as the friction between the yarns and their crossovers and the friction between projectile and fabric during impact. The numeric results confirmed the contribution of frictional properties induced by STF impregnation in restriction of the yarns within the fabric and consequently improving the ballistic properties of woven structures.

This study focuses on the puncture resistance performance of woven high modulus polypropylene (HMPP) fabric impregnated with shear-thickening fluids (STFs) composed of fumed silica nanoparticles suspended in polyethylene glycol (PEG). The puncture resistance performance of STF-treated HMPP fabrics were evaluated by the quasi-static puncture test. The results showed that the STF-treated fabric exhibited significant enhancement in puncture resistance performance as compared to neat fabric. The possible improving mechanisms responsible for puncture resistance performance of STF-treated fabric were also discussed.

Experimental and numerical studies were conducted to analyze the ballistic penetration of high strength aluminium alloy 2014-T652. Hardened steel balls were launched using a propellant gun at velocities ranging from 800 to 1300 m/s to cover regions below and above the ballistic limit. Failure in target plates occurred due to a combination of failure mechanisms such as hydrodynamic flow, spalling, ductile hole growth and scabbing. Tensile tests were conducted at different stress triaxialities, strain rates and temperatures to calibrate the material parameters of Johnson-Cook plasticity and fracture model. Finite element analyses of all the impact experiments were carried out using a two dimensional axisymmetric model. Johnson-Cook fracture model was not able to simulate the quasi-brittle fracture of material and numerical ballistic limit velocity was overestimated. Numerical simulations were repeated using hydrostatic tensile stress failure model along with non-linear equation of state, which resulted in excellent correlation with experimental results.

Ethnopharmacological relevance Tinospora cordifolia (Willd. Hook. f. & Thomson; family: Menispermaceae), has a long history of use in various traditional medicinal systems including “Ayurveda”. It is reported to possess anticancer, antidiabetic, antimicrobial, antispasmodic, and antiinflammatory activities. T. cordifolia has also been well documented for production of various bioactive metabolites and their antioxidant activity, but the microorganisms associated with it have been least explored for the same properties. Aim of the study Aim of the present study was to evaluate antioxidant and in vivo genoprotective potential of phenolic compounds produced by an endophytic fungus Cladosporium velox TN-9S isolated from T. cordifolia . Materials and methods The isolate of C. velox TN-9S was cultivated in malt extract medium and extracted with ethyl acetate. Total phenol content was determined by Folin Ciocalteu reagent. The antioxidant activity was measured in terms of DPPH and FRAP assay. The in vivo genoprotective activity was assessed using fish Channa punctatus as model. Identification of phenolic compounds was carried out using RP-HPLC. The fungal extract was evaluated for biosafety using Salmonella typhimurium His - strain and CHO cell lines for mutagenicity and cytotoxicity, respectively. Results The total phenolic content in the ethyl acetate extract of the fungus was determined to be 730 μg gallic acid equivalent/mL. The extract evinced significant antioxidant activity with IC 50 value of 22.5 µg/mL in DPPH scavenging assay. The phenolic extract showed good in vivo genoprotective activity against the genetic damage induced in fish C. punctatus after treatment with a non-ionic surfactant 4-nonylphenol. RP-HPLC analysis revealed the presence of peaks corresponding to various phenolic compounds in the extract. Mutagenicity and cytotoxicity results revealed the extract to be nonmutagenic and non cytotoxic in nature. Conclusion The results indicate the potential of an endophytic C. velox isolated from T. cordifolia as a producer of phenolic compounds with antioxidant and genoprotective activities which could be exploited in pharmaceutical industry. The ability of endophytes to produce similar compounds as the host, is also revealed in the present study.

Laccases are multicopper oxidases known to catalyze the transformation of a wide range of phenolic and non-phenolic substrates using oxygen as electron acceptor and forming water as the only by product. Their potential relevance in several industries requires the constant search for novel laccases. Positive outcome of the isolation of laccase producing bacteria depends on the nature and concentration of media constituents. Several attempts to isolate laccase producing bacteria failed when the phosphate-containing M9 minimal medium was used. Shift to phosphate-less M162 medium led to successful isolations. Seven bacterial isolates belonging to genera Bacillus, Lysinibacillus, Bhargavaea and Rheinheimera were used to study the effect of medium constituents on laccase production. Inorganic phosphate (≥50 mM) was found to regulate laccase synthesis negatively though no inhibitory effect of phosphate (10-500 mM) was seen on laccase activity. All isolates ceased laccase synthesis when grown in the presence of tryptone (0.2-1%), with R. tangshanensis as an exception, or yeast extract (1.5-2%) as the only C/N source in M162 medium. Supplementation upto 0.1% of glucose in basal M162 medium increased laccase production in five isolates but decreased at higher concentrations. The influence of medium components on laccase synthesis was further affirmed by zymographic studies. These observations offer possibilities of isolating promising laccase producers from diverse environmental sources. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:541-548, 2017.

Objective: The present study projected to the synthesis of 3b-Hydroxy-lup- 20(29)-en-28-oic acid analogues in order to evaluate their possible biological activity. In addition, the structure–activity relationship is also investigated. Method: BA derivatives were prepared by conjugating 3b-Hydroxy-lup- 20(29)-en-28-oic acid with different amines through carbomyl linkage. Structures of synthesized compounds were elucidated by spectral data. Cytotoxic evaluation was done by CAM assay and MTT assay. Results: Among the synthesized compounds, Compound 7showed a pronounced cytotoxicity in antiangiogenic assay as well as compound ECV-304 cell line. Compound 10 also showed good cytotoxic activity. While compounds 6 and 8 showed moderate activity against A-549 and MCF-7 respectively. Conclusion: It is concluded that synthesized BA analogues are biologically active and developed into useful anticancer agents. Key words: Triterpenoids, Lupenoic acid, Carbomyl Linkage, Anticancer activity, MTT Assay.

Low pressure cold gas dynamic spray (LPCGDS) is a coating process that utilize low pressure gas (5–10 bars instead of 25–30 bars) and the radial injection of powder instead of axial injection with the particle range (1–50 μm). In the LPCGDS process, pressurized compressed gas is accelerated to the critical velocity, which depends on length of the divergent section of nozzle, the propellant gas and particle characteristics, and the diameters ratio of the inlet and outer diameters. This paper presents finite element modeling (FEM) of powder stream in supersonic nozzle wherein adiabatic gas flow and expansion of gas occurs in uniform manner and the same is used to evaluate the resultant temperature and velocity contours during coating process. FEM analyses were performed using commercial finite volume package, ANSYS CFD FLUENT. The results are helpful to predict the characteristics of powder stream at the exit of the supersonic nozzle.

Modern Technology has become an integral part of every aspect of our day-to-day life. Education system is also going through a big transformation these days with the introduction of multimedia tools in delivering the knowledge. Along with these tools, [6]Online Education has become a big leap in the advancement of the Education system. The way a person is taught lays a huge impact on the person’s mindset towards the world. With the Online Education the major factor affecting the quality of education has shifted from the ability of the teacher to the enthusiasm of the learner to learn new things.

The unique surface edge states make topological insulators a primary focus among different applications. In this article, we synthesized a large single crystal of Niobium (Nb)-doped Bi2Se3 topological insulator (TI) with a formula Nb0·25Bi2Se3. The single crystal has characterized by using various techniques such as Powder X-ray Diffractometer (PXRD), DC magnetization measurements, Raman, and Ultrafast transient absorption spectroscopy (TRUS). There are (00l) reflections in the PXRD, and Superconductivity ingrown crystal is evident from clearly visible diamagnetic transition at 2.5 K in both FC and ZFC measurements. The Raman spectroscopy is used to find the different vibrational modes in the sample. Further, the sample is excited by a pump of 1.90 eV, and a kinetic decay profile at 1.38 eV is considered for terahertz analysis. The differential decay profile has different vibrations, and these oscillations have analyzed in terms of terahertz. This article not only provides evidence of terahertz generation in Nb-doped sample along with undoped sample but also show that the dopant atom changes the dynamics of charge carriers and thereby the shift in the Terahertz frequency response. In conclusion, a suitable dopant can be used as a processor for the tunability of terahertz frequency in TI.

An enzyme cocktail (xylanase-15U, pectinase-2U, α-amylase-2.5U, protease-2U and lipase- 1.8U) from Bacillus halodurans was applied for the biobleaching of unbleached and ODL (oxygen delignification) agro based pulp in the R&D set up of Shreyans Paper Mills Ludhiana, India, upscaling from 5 g (at lab scale) to 100 g odp (oven dried pulp). Enzyme pre-treatment was carried out at temperature and pH optima of 65 °C and 9–9.5 for 90 min followed by reduced chemical treatment. In case of unbleached agro pulp, as compared to the total chemical bleaching in mill, enzyme cocktail pre-treatment reduced the chemical usage by 50% without compromising brightness and rather with increased tensile strength (23.55%), burst factor (20.3%) and tear factor (3.17%) and reduced kappa number (19.5%). In case of ODL pulp, enzyme cocktail pre-treatment reduced the chemical usage by 40%, yet increasing brightness (2.24%), tensile strength (20.96%), burst factor (5.1%) and tear factor (8.2%) with reduction in kappa number (4.54%). The enzyme cocktail thus can make the paper manufacturing process greener, safer, economical and eco-friendly and may replace big budget ODL technologies.

Polyurea, a reaction product of isocyanates and an amine blend has been reported to be highly strain rate sensitive, which responds in its own unique way when subjected to increasing strain rates. The amine blend comprise of a long chain amine, forming the soft segments, chain extender, which brings the urea linkages closer and a crosslinker, which serves as a chemical bond between the chains. In this work, we attempt to tune the viscous contribution in polyurea, by increasing crosslinking density, while keeping the amount of chain extender more or less constant. The viscoelastic behavior and its effect on the time dependant behavior was established by extensive dynamic studies. Quasi-static tests and Split Hopkinson testing was performed over large deformation rates (10−4 to 103 s−1). It was observed that polyureas with larger viscous contribution (tan δ), were capable of exhibiting larger strain rate sensitivity.

A putative multicopper oxidase, encoded as CopA in the proteome of Acinetobacter baumannii 19606, and designated as AbMCO, was expressed heterologously in E. coli (pET-28a) and purified by Ni-NTA affinity chromatography. The purified AbMCO exhibited in vitro oxidase activities upon exogenous addition of ≥1 μM copper ions. Kinetic studies revealed its phenol oxidase activity as it could catalyze the oxidation of substrates viz. 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), guaiacol, pyrogallol and catechol. Additionally, AbMCO displayed siderophore oxidase activity which depicted its role in metal homeostasis and protection from the toxic redox states of copper and iron. Importantly, expression of abMCO increased manifold upon challenge with high concentrations of copper sulphate (CuSO4, 1.5 mM) and sodium chloride (NaCl, 700 mM) which suggested its protective role in stress adaptation and management. Intra-macrophage assay of abMCO-expressing and abMCO-non expressing cells depicted no significant change in the survival rate of A. baumannii inside the macrophages. These findings indicate that A. baumannii encodes a multicopper oxidase, conferring copper tolerance and survival under stress conditions but had no role in virulence of this pathogen.

The solution for handling the issue of mobile data is gaining significance due to the exponential rise in data traffic in recent years. Data traffic offloading becomes a challenging problem, if it is dependent only on infrastructure (femtocells, Bluetooth, WiFi). Opportunistic communications(mobile social networks, Delay tolerant networks) can enhance the offloading efficiently if the target nodes(helper nodes) are chosen optimally. In this paper, we have considered this problem and propose a Target Set Selection algorithm based on Opinion Dynamics. The opinion vector provides a weighed feedback for the community to select the helper nodes. To validate our algorithm, we have compare it with existing algorithm like heuristic approach and greedy approach of target set selection. Our result shows that the number of nodes identified in the Target Set can further be reduced by nearly 13% when compared with degree based greedy approach. Result also shows that our approach is nearly 58% better than the heuristic approach, infrastructure-based approach in terms of traffic forwarding via helper node.

The acquisition of metal ions such as iron, copper and manganese is essential for the survival of microorganisms as these are constituents of metalloproteins including enzymes, storage proteins, structural elements, transcription factors and antimicrobial factors in various biological processes. However, excess of these metal ions is associated with significant toxicity due to spontaneous redox cycling of ions and obstruction of normal metabolic pathways. To overcome this, microbes have developed a variety of metal regulatory systems allowing them to adapt to the changing biotic and abiotic environments. Multi-copper oxidases (MCOs) such as ceruloplasmins, ferroxidases, laccases and nitrite reductases are such regulatory systems employed by microbes to resist the toxicity of metal ions by controlling their oxidation states under aerobic conditions. MCOs help pathogens survive during an infection by evasion of the toxic environment generated by the host immune system and thus are considered necessary determinants of virulence. This review summarizes the role of MCOs in metal homeostasis under stressful conditions and the extent to which these MCOs contribute to microbial virulence within the host that might prove as an esteemed avenue for the development of novel antimicrobial therapies.

Staphylococcus warneri, isolated from the cervix of an adult female with unexplained infertility, was found to agglutinate human spermatozoa in vitro leading to their death. A genomic library of S. warneri was generated using pSMART-Escherichia coli vector-host system. Approximately 3500 transformants were screened and four showed sperm agglutinating activity. Sperm agglutinating proteins (SAPs) were partially purified from the positive transformants and were found to agglutinate sperms in vitro. Cloned ORFs in positive transformants were sequenced and ORF finder identified them as endonuclease, accessory secretory protein-Asp1, accessory secretory protein-Asp2 and signal transduction protein. Mannose was found to competitively inhibit sperm agglutination, indicating that SAPs in S. warneri bind to mannose in glycoprotein receptors on the surface of sperms for agglutination. This is the first report on identification of SAPs which may be responsible for unexplained infertility in women and may be used as contraceptive agents. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12088-018-0766-5) contains supplementary material, which is available to authorized users.

Quorum sensing plays important roles in the regulation of physiological and virulence processes in most bacteria, but its role in extremophiles is largely unknown. Comparative genomic, phylogenic, structural and signaling pathways analyses and deletion mutant studies have suggested the presence of three major quorum sensing systems (AI-1, Peptide based and AI-2) in extremophiles. Autoinducer-1(AI-1) system was found to be most prevalent (except in thermophiles where it is autoinducer-2) while peptide based system was least prevalent in extremophiles. Some unknown mechanisms of quorum sensing have also been reported which need further exploration. Quorum sensing is utilized by extremophiles for processes like cold adaptation, lowering the freezing point, biofilm formation, oxidative stress resistance and persister cell formation. Explication of quorum sensing in extreme environments may provide discernment regarding the role and functional strategies for survival of extremophiles. Here the role of quorum sensing in different classes of extremophiles and also in their survival strategies has been reviewed. Further, the applications and problems caused by quorum sensing regulated factors in extreme environments are discussed.

Laccases are unable to oxidize the non-phenolic components of complex lignin polymer due to their less redox potential (E0). Catalytic efficiency of laccases relies on the mediators that potentiates their oxidative strength; for breaking the recalcitrant lignin. Laccase from Bacillus sp. SS4 was evaluated for its compatibility with natural and synthetic mediators. (2 mM). It was found that acetosyringone, vanillin, orcinol and veratraldehyde have no adverse effect on the laccase activity up to 3 h. Syringaldehyde, p-coumaric acid, ferulic acid and hydroquinone reduced the enzyme activity ≥50% after 1.0 h, but laccase activity remained 100 to ~120% in the presence of synthetic mediators HBT (1-Hydroxylbenzotrizole) and ABTS. (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) after 3 h. MgSO

Acinetobacter baumannii is an emerging multi-drug resistant pathogen causing significant mortality in hospitalized ICU patients which demands developing new methods for prevention and treatment. A. baumannii 19606 proteome was analysed in silico through the online tool Vaxign for finding potential vaccine candidates. The selected nuclease (NucAb) was predicted to possess all the attributes of a promising vaccine candidate like outer membrane localization, high adhesin probability (0.53), one transmembrane helix only, non-homology to human proteins and presence of B-cell and T-cell epitopes binding with high affinity (percentile rank≤1) to HLA alleles prevalent at high frequency in North Indian populations. nucAb gene was highly prevalent (100%) among the clinical isolates (40/40) and conserved (>98%) among NCBI sequenced Acinetobacter strains. It was cloned in pET28a, purified and its immunoprotective potential was validated in murine pneumonia model. Immunization of BALB/c mice with recombinant NucAb (25μg) elicited high antibody titre (1-5×10(5)) which reduced bacterial load by 5 log cycles in lungs of mice challenged with optimized lethal dose (10(8)CFU). Lung histopathology revealed marked suppression of inflammation. Pro-inflammatory cytokines (TNF-α and IL-6) levels were reduced significantly and anti-inflammatory (IL-10) cytokine increased in lungs and serum leading to decreased severity and slow progression of disease. Though active immunization showed low survival rate (20%), passive immunization improved the survival (40%). This is the first study reporting an outer membrane nuclease as a vaccine candidate in Gram negative bacterium, A. baumannii through reverse vaccinology approach.

The microspheres of Isabgol husk were prepared by emulsification-crosslinking technique and the gastrointestinal transition behavior of the formulation was studied by gamma scintigraphy. The impact of different process variables such as amount of glutaraldehyde, concentration of Isabgol husk and temperature was studied on surface morphology and mucoadhesion. In vitro mucoadhesive testing of formulations was performed by determination of zeta potential, mucus glycoprotein assay and mucus adsorption isotherms. The effect of feeding on retention of microspheres in the gastrointestinal track (GIT) was studied in albino rabbits by gamma scintigraphy study. The results indicated the formation of microspheres as observed by scanning electron microscopy. The smooth and round surfaces of microspheres were obtained on increasing Isabgol husk and glutaraldehyde amount. The positive zeta potential of all formulations indicated the electrostatic interaction as a mechanism of mucoadhesion between the mucus of GIT membranes and the microspheres surfaces. The influence of electrostatic interaction on mucoadhesion of microspheres was again ascertained when the mucin equilibrium adsorption on preparations indicated well fitness in Langmuir and Freundlich adsorption isotherms. During gamma scintigraphy, the stability of (99m)Tc-sodium pertechnetate was found 98.82% at pH 6.8 and 96.78% at pH 7.2, respectively. It indicated the minimal leaching of bound radionuclide from microspheres during gastrointestinal transition as observed in gamma scintigraphic images of the rabbits. The microspheres retained in GIT even after 24 hrs of oral administration. The results indicated the applicability of Isabgol husk mucilage in the development of mucoadhesive microspheres.

Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant and its increased use in common products such as plastics, electronic equipment, etc., has raised concern about its ecotoxicity. The present study was conducted to investigate the oxidative stress and genotoxic potential of TBBPA on fresh water fish

In the present study, an extracellular alkali stable laccase (Lac DS) from Bacillus subtilis DS which has pH optima at 8.5 using p-phenylenediamine (PPD) as substrate has been reported. Lac DS retained 70% activity for 4 h at pH 8.5 and 90% activity for 24 h at 55 °C. The enzyme yield was enhanced by optimization of fermentation conditions. A 746-fold increase in yield was observed under optimized conditions using 150 µM MgSO(4), 1.2% yeast extract, 0.35% tryptone, and 150 µM vanillic acid. Lac DS was used to polymerize natural dye precursor catechol, pyrogallol, syringaldehyde, syringic acid, ferulic acid and gallic acid to develop a range of natural hair colors such as black, golden yellow, and reddish brown. The results indicate that alkaline Lac DS is a suitable candidate to develop a user-friendly and commercially applicable hair dyeing process in the area of cosmetic industry. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13205-018-1181-7) contains supplementary material, which is available to authorized users.

Treatments of industrial effluent/s by enzymes offer significant advantage over the use of microorganisms. However they have not been explored for the bioremediation of effluent from pulp and paper industry. This may be because of the less availability of lignolytic enzymes which can be active/stable under extreme environmental conditions that are present in effluent treatment plant of pulp and paper mills. In present study use of thermoalkali stable laccase from Bacillus tequilensis SN4 has been explored for the bioremediation of paper mill effluent. Under standardized conditions significant reduction in various parameters , color 83%, BOD 82%, COD 77%, phenol content 62%, lignin content 74%, TDS 28% and TSS 34%, was achieved. Major advantage was that treatment time was only 4h, much less than the bioremediation reported with the use of microorganisms, which is usually four to five days. Results indicate that SN4 laccase is very suitable to develop a process for the effective bioremediation of effluent from pulp and paper industry.

Xylanase-producing Bacillus halodurans FNP 135 was applied for biobleaching of kraft pulp through submerged (SmF) and solid state fermentation (SSF). SmF showed better delignification than SSF with 35 and 30% decrease in kappa number, 5.8 and 4.3% increase in brightness, 8.7 and 6.7% increase in breaking length, 13.7 and 12% increase in burst factor, 20.7 and 17.5% increase in tear factor and 8.6 and 3.3% increase in viscosity respectively. Surface composition of SmF treated pulp fibers and morphological characteristics were studied by X-ray diffraction, Fourier transform infra red spectroscopy and scanning electron microscopy. Significant changes were observed in fiber surface functional groups indicated delignification and cellulose crystallinity increased marginally. Biobleaching resulted in 20 (SmF) and 10 (SSF) % reduction in chlorine consumption. Electron microscopy revealed that fiber surface became more fibrillar and rough with an appearance of pores and flakes on it. The present work can help to make the paper manufacturing process cleaner and ecofriendly.

Background Quorum sensing is a mechanism of cell to cell communication that requires the production and detection of signaling molecules called autoinducers. Although mesophilic bacteria is known to utilize this for synchronization of physiological processes such as bioluminescence, virulence, biofilm formation, motility and cell competency through signaling molecules (acyl homoserine lactones, AI-1; oligopeptides, peptide based system and furanosyl borate diester, AI-2), the phenomenon of quorum sensing in thermophiles is largely unknown. Results In this study, proteomes of 106 thermophilic eubacteria and 21 thermophilic archaea have been investigated for the above three major quorum sensing systems to find the existence of quorum sensing in these thermophiles as there are evidences for the formation of biofilms in hot environments. Our investigation demonstrated that AI-1 system is absent in thermophiles. Further, complete peptide based two component systems for quorum sensing was also not found in any thermophile however the traces for the presence of response regulators for peptide based system were found in some of them. BLASTp search using LuxS (AI-2 synthase) protein sequence of Escherichia coli str. K-12 substr. MG1655 and autoinducer-2 receptors (LuxP of Vibrio harveyi, LsrB of E. coli str. K-12 substr. MG1655 and RbsB of Aggregatibacter actinomycetemcomitans) as queries revealed that 17 thermophilic bacteria from phyla Deinococcus- Thermus and Firmicutes possess complete AI-2 system (LuxS and LsrB and/or RbsB). Out of 106 thermophilic eubacteria 18 from phyla Deinococcus- Thermus, Proteobacteria and Firmicutes have only LuxS that might function as AI-2 synthesizing protein whereas, 16 are having only LsrB and/or RbsB which may function as AI-2 receptor in biofilms. Conclusions We anticipate that thermophilic bacteria may use elements of LsrB and RbsB operon for AI-2 signal transduction and they may use quorum sensing for purposes like biofilm formation. Nevertheless, thermophiles in which no known quorum sensing system was found may use some unknown mechanisms as the mode of communication. Further information regarding quorum sensing will be explored to develop strategies to disrupt the biofilms of thermophiles. Electronic supplementary material The online version of this article (10.1186/s12866-018-1204-x) contains supplementary material, which is available to authorized users.

Laccases have potential applications in industrial, biotechnological, and environmental set ups. Development of cost effective and efficient production technologies has gained significant attention in recent years. To enhance the laccase production from Rheinheimera sp. (Gram negative) using submerged fermentation (SmF) and from Lysinibacillus sp. (Gram positive) using solid-state fermentation (SSF), the inducing effect of various flavonoid-rich agro-industrial residues was investigated. Peels of citrus fruits, soybean meal, tofu dreg, lignin monomers, and lingo-cellulosic waste, used tea leaves and peels of onion and kiwi, paper, and dying industry effluents were tested as inducers. In SmF, 0.1% of soybean meal, tofu dreg, and powdered orange peel were best, enhancing the laccase production 2.57-, 2.11-, and 2.05-fold, respectively. In SSF, 10 mg (w/w) of used tata acti green tea leaves per 5 g of wheat bran, 1% pulp and paper industry effluent (agro based), and 1% wine made from Sygium cumini enhanced the laccase production 2.69-, 2.61-, and 2.09-fold, respectively. These results suggest the utilization of these flavonoid and phenolic-rich waste materials to be potential enhancers of industrially important laccase production.

Quasi-static to dynamic compression behavior of Kota sandstone is investigated herein under low (0.00001–0.1/s) and medium (1/s) strain rates in order to characterize the rate-dependent stress–strain response of the sandstone found in the region of Kota in India. Both quasi-static and dynamic tests are performed in a universal testing machine. From the stress–strain response of Kota sandstone, the effect of strain rate on peak stress, failure strain and modulus of elasticity have been studied. It is observed that with the increase in strain rate, the peak stress of sandstone increases. The failure strain and the modulus of elasticity also increase with increase in strain rate. Conversely, peak stress decreases for the tests which are carried out at a rate slower than usual static test. The strength increase factor of Kota sandstone, namely the dynamic increase factor (DIF) has been calculated. Based on the results obtained from the tests conducted on the sandstone, an empirical equation has been developed for correlating the DIF with the applied strain rates. Further, effect of rock sample diameter and aspect ratio on strain rate dependent strength of rock has been studied. Correction equations have been developed for taking into account the effect of sample sizes as per the ASTM D7012-13 on the peak stress in Kota sandstone.

New frontiers of therapy are being explored against the upcoming bacterial diseases rendered untreatable due to multiple, extreme and pan- antibiotic resistance. Nucleases are ubiquitous in bacterial pathogens performing various functions like acquiring nucleotide nutrients, allowing or preventing uptake of foreign DNA, controlling biofilm formation/dispersal/architecture, invading host by tissue damage, evading immune defence by degrading DNA matrix of neutrophil extracellular traps (NETs) and immunomodulating the host immune response. Secretory nucleases also provide means of survival to other bacteria like iron-reducing Shewanella and such functions help them adapt and survive proficiently. Other than their pro-pathogen roles in survival, nucleases can be used directly as therapeutics. One of the powerful armours of pathogens is the formation of biofilms, thus helping them resist and persist in the harshest of environments. As eDNA forms the structural and binding component of biofilm, nucleases can be used against the adhering component, thus increasing the permeability of antimicrobial agents. Nucleases have recently become a model system of intense study for their biological functions and medical applications in diagnosis, immunoprophylaxis and therapy. Rational implications of these enzymes can impact human medicine positively in future by opening new ways for therapeutics which have otherwise reached saturation due to multi drug resistance.

Pseudomonas aeruginosa possesses an arcade of both cell-associated and extracellular cytotoxic virulence factors which are regulated by a multi-component quorum sensing system. Many research studies report success of lactonase in combating the pathogenicity of P. aeruginosa but delivery of lactonase remains a challenge. The present study aims at developing a delivery vehicle for lactonase. Lactobacillus plantarum NC8 was used as host for aiiA (Bacillus thuringiensis 4A3 lactonase gene) using pSIP409 expression vector. pSIP409: aiiA construct was stably maintained in L. plantarum NC8. Co-culturing of multi-drug resistant (MDR) clinical isolates of P. aeruginosa and PAO1 with recombinant L. plantarum NC8 led to significant reduction (p < 0.001) in extracellular virulence factors like pyocyanin, protease, elastase and rhamnolipids in P. aeruginosa and also showed significant reduction in adhesion of P. aeruginosa strains to uroepithelial cells in vitro. This study shows the heterologous expression of AiiA lactonase in L. plantarum NC8. Co-culturing of lactonase expressing L. plantarum NC8 with MDR P. aeruginosa strains led to attenuation of their virulence significantly. These results underscore the potential application of recombinant L. plantarum NC8 with anti-quorum sensing properties to control infections caused by multidrug resistant P. aeruginosa.

Degradation of residual lignin in kraft pulp by chemical bleaching is implicated in causing environmental pollution. The use of thermo- and alkali-tolerant bacterial laccases is considered to be important biological alternative to chemical processing. Laccases from Bacillus species have shown promise in this respect but their intracellular/spore bound presence make their industrial application economically unfeasible. We report here on a novel extracellular active thermo-alkali-stable laccase (SN4 laccase) which is active at 90 °C and pH 8.0 using 2,6-dimethoxyphenol as substrate from Bacillus tequilensis SN4. SN4 laccase retained 27 % activity for 5 min at 100 °C and more than 80 % activity for 24 h at 70 °C. The enzyme is also stable at a higher pH (9.0–10.0). Enzyme production was optimized by submerged fermentation. Relatively high yields (18,356 nkats ml−1) of SN4 laccase was obtained in a medium containing 650 μM MnSO4, 350 μM FeSO4, and 3.5 % ethanol. A 764-fold increase in laccase activity was observed under optimal conditions. In addition, reduction in kappa number and increase in brightness of softwood pulp by 28 and 7.6 %, respectively, were observed after treatment with SN4 laccase without a mediator. When N-hydroxybenzotriazole was used as a mediator, the kappa number was decreased to 47 % and brightness was increased to 12 %.

An alkali-thermostable β-mannanase from Bacillus nealsonii PN-11 was purified 38.96-fold to homogeneity with specific activity of 2,288.90 ± 27.80 U mg−1 protein and final recovery of 8.92 ± 0.09 %. The purified β-mannanase was an extracellular monomeric protein with a molecular mass of 50 kDa on SDS–PAGE. The first 20 N-terminal amino acid sequence of mannanase enzyme was MVVKKLSSFILILLLVTSAL. The optimal temperature and pH for enzyme were 65 °C and 8.8, respectively. It was completely stable at 60 °C for 3 h and retained >50 ± 1.0 % activity at 70 °C up to 3 h. The β-mannanase was highly stable between pH 5–10 and retained >85 % of the initial activity for 3 h. The metal ions Ni+2, Co+2, Zn+2 and Mg+2 enhanced the enzyme activity. The enzyme remained stable after 3 h of preincubation with most of the tested organic solvents. According to substrate specificity study, the purified mannanase had high specificity to locust bean gum which was degraded mainly to mannooligosaccharides (MOS) like mannotriose, mannotetraose and mannopentose. These MOS enhanced the growth of Lactobacillus casei but inhibited the growth of Salmonella enterica indicating potential prebiotic properties. The properties of the purified β-mannanase from B. nealsonii PN-11 make this enzyme attractive for biotechnological applications.

Mannan is the main polysaccharide component of coffee extract and is responsible for its high viscosity, which in turn negatively affects the technological processing involved in making instant coffee. In our study, we isolated mannan from coffee beans and extract of commercial coffee and it was enzymatically hydrolyzed using alkali-thermostable mannanase obtained from Bacillus nealsonii PN-11. As mannan is found to be more soluble under alkaline conditions, an alkali-thermostable mannanase is well suited for its hydrolysis. The process of enzymatic hydrolysis was optimized by response surface methodology. Under the following optimized conditions viz enzyme dose of 11.50 U mannanase g(-1) coffee extract, temperature of 44.50 °C and time of 35.80 min, significant twofold decrease in viscosity (50 mPas to 26.00 ± 1.56 mPas) was achieved. The application of this process in large-scale industrial production of coffee will help in reduction of energy consumption used during freeze-drying. It will also make technological processing involved in making coffee more economical.

The energy absorption characteristics of silica-filled epoxy composites, for potential application as a blast mitigating retrofitting polymer coating has been explored. Mesoporous silica (SBA-15) with controlled pore size of 5.4 nm was synthesized by the hydrolysis of tetraethyl orthosilicate in the presence of amphiphilic copolymer (PEO-PPO-PEO) which was characterized by nitrogen physisorption studies at 77 K. The porous siliceous rods were homogeneously dispersed in the epoxy resin by ultrasonication (0.5–7 wt%) and subsequently cured using triethylene tetra-amine hardener to prepare silica reinforced composites. Structural, thermal and mechanical properties of the composites were evaluated under dynamic as well as quasi-static conditions which revealed that introduction of SBA-15 at low loadings (1 wt%) led to an increase in the toughness of the base resin but macroporous silica led to deterioration in the properties. The results clearly revealed that the mesoporous nature of silica plays a major role towards improving the dispersion of the filler which in turn resulted in improved properties. Neat epoxy samples fractured in a brittle fashion, but in the presence of SBA-15, the sample exhibited ductile failure, which was explained on the basis of a crack pinning mechanism. High strain rate studies (~103 s−1) of selected compositions were performed on a Split Hopkinson pressure bar and the effect of addition of mesoporous silica on the energy absorption characteristics were established. Finite element analysis was used to predict the behavior of concrete slabs on exposure to dynamic loadings resulting from TNT explosions, both in the presence and absence of the epoxy layer, which revealed the role of the retrofit as a fragment arrestor.

DNA methylation is an epigenetic modification involved in gene expression regulation. In cancer, the DNA methylation pattern becomes aberrant, causing an array of tumor suppressor genes to undergo promoter hypermethylation and become transcriptionally silent. Reexpression of methylation silenced tumor suppressor genes by inhibiting the DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) has emerged as an effective strategy against cancer. The expression of DNA methyltransferase 1 (DNMT1) being high in S-phase of cell cycle makes it a specific target for methylation inhibition in rapidly dividing cells as in cancer. This review discusses nucleoside analogues (azacytidine, decitabine, zebularine, SGI-110, CP-4200), non-nucleoside ihibitors both synthetic (hydralazine, RG108, procaine, procainamide, IM25, disulfiram) and natural compounds (curcumin, genistein, EGCG, resveratrol, equol, parthenolide) which act through different mechanisms to inhibit DNMTs. The issues of bioavailability, toxicity, side effects, hypomethylation resistance and combinatorial therapies have also been highlighted.

Multi-walled carbon nanotubes–polycarbonate composites (MWCNT–PC) were prepared by a two-step method of solvent casting followed by compression molding and their dynamic impact strength was studied. Split Hopkinson Pressure Bar (SHPB) was deployed as the instrument for impact testing of the composite samples. The impact tests were performed under varying strain rates ranging from 1096 to 4017/s. The present studies report the stress–strain behavior of MWCNT–PC composites under a high strain rate of 2000–2600/s. A comparison of stress at various strains ranging from 5% to 20% was done by varying MWCNT concentration in the range 0.1, 0.5, 1, 2 and 5 wt.% in PC. Stress tolerance of these composites was studied to analyze effectiveness of small amounts of carbon nanotubes (CNTs) for impact/stress absorption in comparison to pure PC samples. It was found that the stress behavior for specific strains varies with concentration of CNTs in polycarbonate. At very low (about 0.1 wt.%) and high concentrations (about 5 wt.%) of carbon nanotubes the stress did not vary much as compared to pure PC for the above mentioned strain range. At concentration levels of 0.5, 1 and 2 wt.% CNTs, the impact absorption (nearly 105 MPa) increased by 10–20% as compared to pure PC (nearly 90 MPa) depending upon the amount of strain in the samples. The role of functionalized CNTs in impact studies was also studied by using 0.5 wt.% and 2 wt.% functionalized MWCNT. The use of functionalized CNTs was found to result in reduced impact absorption (nearly 95 MPa) as compared to as-synthesized CNTs (nearly 105 MPa). The effect of concentration of CNTs on impact strength of MWCNT–PC composites was analyzed by studying the SEM images of composite samples after impact.

This paper presents the experimental results to analyze the strain rate sensitivity of aluminium alloy AA-5052 H34. The experiments were carried out under uniaxial tension as well as compression. Tensile tests were carried out with UTM (Zwick Z-250) in the strain rate range of 10-4 to 10-1 s-1 using standard ASTM specimen with gauge length 50mm. Compression tests were carried out in the strain rate range of 10-4 to 103 s-1 using UTM and Split Hopkinson Pressure Bar. Cylindrical specimens of 10mm diameter and 10mm thickness were used for compression experiments. The material showed negative strain rate sensitivity in strain rate from 10-4 to 1 s-1 but showed positive strain rate sensitivity when strain rate increased to 103 s-1. The material was found to be susceptible to Portevin–Le Chatelier effect.

Activated sludge is an artificial ecosystem known to harbor complex microbial communities. Bacterial diversity in activated sludge from pulp and paper industry was studied to bioprospect for laccase, the multicopper oxidase applicable in a large number of industries due to its ability to utilize a wide range of substrates. Bacterial diversity using 454 pyrosequencing and laccase diversity using degenerate primers specific to conserved copper binding domain of laccase like multicopper oxidase (LMCO) genes were investigated. 1231 OTUs out of 11,425 sequence reads for bacterial diversity and 11 OTUs out of 15 reads for LMCO diversity were formed. Phylum Proteobacteria (64.95 %) with genus Thauera (13.65 %) was most abundant followed by phylum Bacteriodetes (11.46 %) that included the dominant genera Paludibacter (1.93 %) and Lacibacter (1.32 %). In case of LMCOs, 40 % sequences showed affiliation with Proteobacteria and 46.6 % with unculturable bacteria, indicating considerable novelty, and 13.3 % with Bacteroidetes. LMCOs belonged to H and J families.

Acinetobacter baumannii and Pseudomonas aeruginosa are pathogens capable of colonizing the same infection sites and employing N-acyl homoserine lactone (AHL) based quorum-sensing systems to co-ordinate biofilm formation. Hence, the effect of P. aeruginosa AHLs on biofilm formation by A. baumannii and vice versa were investigated using the biofilm impaired quorum sensing mutants, A. baumannii M2 (abaI::Km) and P. aeruginosa PAO-JP2. Complementing the mutants with heterologous, extracted and pure AHLs increased biofilm mass significantly. The surface area coverage and biovolume also increased significantly as observed by confocal scanning laser microscopy which corroborated scanning electron microscope analysis. Autoinducer synthase gene promoters of A. baumannii, P( abaI)-lacZ, and P. aeruginosa, P( lasI)-lacZ, were induced (p 0.05) by heterologous AHLs. Growth of A. baumannii was not inhibited by pyocyanin of P. aeruginosa which may allow their co-existence and interaction in the clinical setting, thereby affecting the severity of combined infections and therapeutic measures to control them.

Mannans are the major constituents of the hemicellulose fraction in softwoods and show widespread distribution in plant tissues. The major mannan-degrading enzymes are β-mannanases, β-mannosidases and β-glucosidases. In addition to these, other enzymes such as α-galactosidases and acetyl mannan esterases, are required to remove the side chain substituents. The mannanases are known to be produced by a variety of bacteria, fungi, actinomycetes, plants and animals. Microbial mannanases are mainly extracellular and can act in wide range of pH and temperature because of which they have found applications in pulp and paper, pharmaceutical, food, feed, oil and textile industries. This review summarizes the studies on mannanases reported in recent years in terms of important microbial sources, production conditions, enzyme properties, heterologous expression and potential industrial applications.

Laccases (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) are multi-copper-containing enzymes capable of catalyzing the oxidation of a wide range of phenolic and non phenolic aromatic compounds. The available data indicates that laccases from prokaryotes are promising biological tools for green chemistry based applications, especially in decolorization of industrial textile dye effluents which constitute a major threat to soil and ground water reservoirs worldwide. Another appropriate application of prokaryotic laccases is bio-bleaching of different kind of pulps where there is indiscriminate use of hazardous chlorine based chemicals for brightness of the paper. In recent years, researchers have shown interest in the identification and characterization of laccases from prokaryotic sources. This catalyst is not commonly reported from this kingdom, although prokaryotes have immense environmental adaptability and biochemical versatility. Moreover, true laccases or laccase-like enzymes exist in many gram-negative, gram-positive bacteria and actinomycetes. Corresponding genes have been identified and functionally expressed in genetically developed hosts. This review summarizes the research efforts to characterize laccases and their properties from different prokaryotic sources, including bacteria and actinomycetes.

Laccase, through its versatile mode of action, has the potential to revolutionize the pulping and paper making industry. It not only plays a role in the delignification and brightening of the pulp but has also been described for the removal of the lipophilic extractives responsible for pitch deposition from both wood and nonwood paper pulps. Laccases are capable of improving physical, chemical, as well as mechanical properties of pulp either by forming reactive radicals with lignin or by functionalizing lignocellulosic fibers. Laccases can also target the colored and toxic compounds released as effluents from various industries and render them nontoxic through its polymerization and depolymerization reactions. This article reviews the use of both fungal and bacterial laccases in improving pulp properties and bioremediation of pulp and paper mill effluents. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2012

Acinetobacter is emerging as one of the major nosocomial infectious pathogens, facilitated by tolerance to desiccation and multidrug resistance. Quorum sensing (autoinducer-receptor mechanism) plays role in biofilm formation in Acinetobacter, though its role in regulation of other virulence factors is yet to be established. Phylogenetic studies indicate that Acinetobacter baumannii is closely related to Burkholderia ambifaria but its quorum sensing genes (abaI and abaR) were acquired horizontally from Halothiobacillus neapolitanus. The prospects of quorum quenching to control the infections caused by Acinetobacter have also been discussed.

The crude tea polyphenols of regular black tea were investigated in vitro for effect on virulence traits of Shigella dysenteriae and Enteropathogenic Escherichia coli (EPEC P2 1265) strains. Results showed that crude tea polyphenols of black tea significantly increased (p acid un-adapted, tea un-adapted > acid adapted, tea adapted > acid un-adapted, tea-adapted. These results inferred that polyphenolic treatment of bacterial culture disrupts pH hemostasis which caused complete bacterial killing in 120 min when compared to tea-untreated culture where complete killing required 180 min. Serum bactericidal activity was also increased in tea-treated culture of EPEC P2 1265 when 2-h serum treatment caused complete bacterial killing but un-treated cells were killed after 3 h. Also, significant increase (p

Using specific egg yolk antibodies (IgY), a strip-based immunochromatographic assay was developed for rapid detection of morphine in urine samples. IgY type antibody against morphine was generated by immunizing chickens with well-characterized monoacetyl morphine–protein conjugate. The antibody was labeled with gold nanoparticles and used as an immunoprobe in the dipstick format for the visual detection of morphine in urine samples. The dipstick was developed using three membranes: an application pad made of glass fiber membrane to hold the tracer, a signal generation test line on nitrocellulose membrane (detection zone) and a cellulose membrane used as an absorption pad. Analytes of interest (morphine and its analogues) added to the sample well, dissolved the labeled antibody (tracer), and the antigen–antibody complex formed was transported by the flow caused by capillary action to the test line. The color signal of test line in proportion to the morphine concentration in urine samples was measured using a detector. The developed dipstick assay format was optimized, showing the average IC50 values of morphine as low as 9.45 ng/mL, the detection range of 1–1000 ng/mL and the lowest detection limit 2.5 ng/mL under optimal conditions of analysis. The correlation between the developed dipstick and ELISA was 0.948 in the analysis of urine samples spiked with morphine. The developed dipstick could be a highly sensitive and convenient tool for rapid detection of opiate drugs in samples with high degree of stability.

Various genotoxic textile dyes, xenobiotics, substrates (10 µM) and agrochemicals (100 µg/ml) were tested for enhancement of alkalophilic laccase activity inγ-proteobacterium JB. Neutral Red, Indigo Carmine, Naphthol Base Bordears and Sulphast Ruby dyes increased the activity by 3.7, 2.7, 2.6 and 2.3 fold respectively. Xenobiotics/substrates like p-toluidine, 8-hydroxyquinoline and anthracine increased it by 3.4, 2.8 and 2.3 fold respectively. Atrazine and trycyclozole pesticides enhanced the activityby 1.95 and 1.5 fold respectively.Vários corantes têxteis genotóxicos, xenobióticos, substratos (10 mM) e agroquímicos (100 mM/mL) foram testados quanto ao aumento da atividade de lacase em γ-Proteobacterium JB. Os corantes Neutral Red, Indigo Carmine, Naphtol Base Bordears e Sulphast Ruby aumentaram a atividade em 3,7, 2,7, 2,6 e 2,3 vezes, respectivamente. Xenobióticos/substratos como p-toluidina, 8-hidroxiquinolina e antracina aumentaram a atividade em 3,4, 2,8 e 2,3 vezes, respectivamente. Atrazina e pesticidas triciclozol aumentaram a atividade em 1,95 e 1,5 vezes, respectivamente.