A novel molecular reporter for probing protein DNA recognition: An optical spectroscopic and molecular modeling study.

A novel benzo[a]phenoxazine-based fluorescent dye LV2 has been employed as a molecular reporter to probe recognition of a linker histone protein H1 by calf-thymus DNA (DNA). Fluorescence lifetime of LV2 buried in the globular domain of H1 (∼2.1 ns) or in the minor groove of DNA (∼0.93 ns) increases significantly to 2.65 ns upon interaction of the cationic protein with DNA indicating formation of the H1-DNA complex. The rotational relaxation time of the fluorophore buried in the globular domain of H1 increases significantly from 2.2 ns to 8.54 ns in the presence of DNA manifesting the recognition of H1 by DNA leading to formation of the H1-DNA complex. Molecular docking and molecular dynamics (MD) simulations have shown that binding of LV2 is energetically most favourable in the interface of the H1-DNA complex than in the globular domain of H1 or in the minor groove of DNA. As a consequence, orientational relaxation of the LV2 is significantly hindered in the protein-DNA interface compared to H1 or DNA giving rise to a much longer rotational relaxation time (8.54 ns) in the H1-DNA complex relative to that in pure H1 (2.2 ns) or DNA (5.7 ns). Thus, via a significant change of fluorescence lifetime and rotational relaxation time, the benzo[a]phenoxazine-based fluorescent dye buried within the globular domain of the cationic protein, or within the minor groove of DNA, reports on recognition of H1 by DNA.

Recent advances in electrochemical sensor developments for detecting emerging pollutant in water environment.

In the latest times, considerable studies have been performed closer to detecting emerging pollutant such as paracetamol in wastewater. Electrochemical sensor developments have recently started to determine in fewer concentrations effectively. The detection of paracetamol using standard protocols corresponding to electroanalytical techniques has a greater impact noticed in directing the detecting process toward biosensors. Non-enzymatic sensors are the peak of all electro analysis approaches. Functionalized materials, such as metal oxide nanoparticles, conducting polymers, and carbon-based materials for electrode surface functionalization have been used to create a fortification for distributing passive enzyme-free biosensors. Synergic effects are possible by enhancing loading capacity and mass transfer of reactants for attaining high analytical sensitivity using a variety of nanomaterials with large surface areas. The main focus of this study is to address the prevailing issues in the identification of paracetamol with the tasks in the non-enzymatic sensors field, followed by the useful methods of electro analysis studies.

TiO2/AgO composites by one step photo reduction technique as electron transport layers (ETL) for dye-sensitized solar cells.

Dye-sensitized solar cell's electron transport layer is responsible for transporting photo-generated electrons to the outer circuit. Utilizing localized surface plasmon resonance (SPR), light absorption could be enhanced to a greater degree, which can drive dye molecules to excited state more effectively than far-field light. In this work, TiO2 nanoparticles were prepared by solvothermal method, and Ag nanoparticles were decorated over TiO2 surface through photodeposition method. XRD data of the TiO2 sample exhibits anatase phase and in the Ag nanoparticle decorated TiO2 sample, peaks corresponding to (111) planes of Ag was observed. UV-Vis absorption analysis of the TiO2 and Ag decorated TiO2 samples showed absorption in the UV region for the TiO2, and the SPR effect was detected for the Ag deposited TiO2 samples. Ag nanoparticles decorated over TiO2 was observed to be spherical in shape through the images from transmission electron microscope. Presence of both Ag and AgO in the prepared sample was revealed through the data from X-ray photoelectron spectroscopy. The prepared material was used as photoanodes in the construction of the DSSCs, and their performance was evaluated.

Enhancement of ultrasound assisted aqueous extraction of polyphenols from waste fruit peel using dimethyl sulfoxide as surfactant: Assessment of kinetic models.

Pomegranate peel, a major waste from the food processing industries containing biologically active compounds, could be converted into value-added products having medicinal properties. Present study deals with the ultrasound-assisted surfactant, namely dimethyl sulfoxide (DMSO) aided polyphenolics extraction from pomegranate peel waste using double distilled water (DDW) as a solvent. Maximum total yield of extraction and total polyphenolic content (TPC) were found respectively to be 43.58 ± 1.0 and 49.55 ± 0.8%, at optimized sonication parameters viz. temperature 50 °C, power density 1.2 W/mL and time 40 min followed by surfactant aided extraction under optimum conditions 0.6% DMSO, 50 °C and 150 rpm for 90 min. Kinetic models were developed to determine the polyphenolics concentration and validated. GC-MS analysis of the extract revealed 22 phenolic compounds. Thus, the acquired results have ensured the significance of ultrasound pre-treated surfactant aided extraction of polyphenolic compounds and this process can be developed for commercial production.

Enhanced photocatalysis and anticancer activity of green hydrothermal synthesized Ag@TiO2 nanoparticles.

Titanium dioxide (TiO2) nanoparticles (NPs) have been doped with varying amounts (0.005, 0.010 and 0.015 M) of silver nanoparticles (Ag NPs) using hydrothermal method. Further, in this work, a green approach was followed for the formation of Ag@TiO2 NPs using Aloe vera gel as a capping and reducing agent. The structural property confirmed the presence of anatase phase TiO2. Increased peak intensity was observed while increasing the Ag concentration. Further, the morphological and optical properties have been studied, which confirmed the effective photocatalytic behavior of the prepared Ag@TiO2 NPs. The photocatalytic performance of Ag@TiO2 has been considered for the degradation of picric acid in the visible light region. The concentration at 0.010 M of the prepared Ag@TiO2 has achieved higher photocatalytic performance within 50 min, which could be attributed to its morphological behavior. Similarly, anticancer activity against lung cancer cell lines (A549) was also determined. The Ag@TiO2 NPs generated a large quantity of reactive oxygen species (ROS), resulting in complete cancer cell growth suppression after their systemic in vitro administration. Ag@TiO2 NPs was adsorbed visible light that leads to an enhanced anticancer sensitivity by killing and inhibiting cancer cell reproduction through cell viability assay test. It was clear that 0.015 M of Ag@TiO2 NPs were highly effective against human lung cancer cell lines and showed increased production of ROS in cancer cell lines due to the medicinal behavior of the Aloe vera gel.

Selective Detection of H2S by Copper Complex Embedded in Vesicles through Metal Indicator Displacement Approach.

A new approach for the detection of hydrogen sulfide (H2S) was constructed within vesicles comprising phospholipids and amphiphilic copper complex as receptor. 1,2-Distearoyl- sn-glycero-3-phosphocholine (DSPC) vesicles with embedded metal complex receptor (1.Cu) sites have been prepared. The vesicles selectively respond to H2S in a buffered solution and show colorimetric as well as spectral transformation. Other analytes such as reactive sulfur species, reactive nitrogen species, biological phosphates, and other anions failed to induce changes. The H2S detection is established through a metal indicator displacement (MIDA) process, where Eosin-Y (EY) was employed as an indicator. Fluorescence, UV-vis spectroscopy, and the naked eye as the signal readout studies confirm the high selectivity, sensitivity, and lower detection limit of the vesicular receptor. The application of vesicular receptors for real sample analysis was also confirmed by fluorescence live cell imaging.

Study on Lipid Accumulation in Novel Oleaginous Yeast Naganishia liquefaciens NITTS2 Utilizing Pre-digested Municipal Waste Activated Sludge: a Low-cost Feedstock for Biodiesel Production.

The economical production of lipids is considered as an appropriate renewable alternative feedstock for biodiesel production because of the contemporary concerns on fuel crisis, climate change and food security. In this study, lipid accumulation potential of a novel oleaginous yeast isolate Naganishia liquefaciens NITTS2 by utilizing pre-digested municipal waste activated sludge (PWAS) was explored. Optimization of culture conditions was performed using response surface methodology coupled with genetic algorithm and maximum lipid content of 55.7% was obtained. The presence of lipid was visually confirmed by fluorescence microscopy and its characteristic profile was determined by GC-MS. The yeast lipid was recovered and converted into biodiesel by garbage lipase with the efficiency of 88.34 ± 1.2%, which was further analyzed by proton nuclear magnetic resonance spectroscopy. Hence, the results of this study strongly suggest the possibility of using PWAS as an efficient and low-cost resource for the production of biodiesel from the oleaginous yeast.

Green synthesis of silver nanoparticles using leaf extract of Acalypha hispida and its application in blood compatibility.

The blood compatibility of AgNPs is of great relevance as it has good antifungal, antibacterial and anti-inflammatory properties and the toxicological information of their effects on cells need to be analyzed before using it as drug carriers in the biomedical field. The present study deals with the synthesis of AgNPs from an aqueous solution of silver nitrate using Acalypha hispida leaf extract as the reducing and capping agent. The presence of AgNPs in the reaction mixture was confirmed by visual observation of color change and subsequently identified using UV-Visible Spectroscopy. XRD results revealed the crystalline nature of synthesized AgNPs. The shape and size of particles were characterized by TEM. These results revealed the elemental status of nanopowder. The components present in leaf extract were identified by GC-MS and functional groups present in the sample when treated with silver nitrate were obtained from FT-IR results. The surface of synthesized AgNPs was modified using four different compounds such as CTAB, PEG, PEI, and APTMS to evaluate the blood compatibility. The results showed that 50 µg/mL CTAB coated AgNPs and 50 and 100 µg/mL PEG coated AgNPs had non-hemolytic property and considered as more blood compatible surface modified AgNPs. This investigation gives an idea of using surface modified AgNPs in the field of biomedicine and therapeutic applications.

On/Off Fluorescent Chemosensor for Selective Detection of Divalent Iron and Copper Ions: Molecular Logic Operation and Protein Binding.

Here, naphthalene diamine-based ß-diketone derivative (compound LH) was successfully used as a dual signaling probe for divalent cations, Fe2+ and Cu2+ ions, in bimodal methods (colorimetric and fluorometric). It showed fluorescent enhancement for Fe2+ ion by photoinduced electron transfer mechanism and fluorescence quenching for Cu2+ ion by charge-transfer process. Binding stoichiometry for [LH-(Fe2+)2] and [LH-(Cu2+)2] was found to be 1:2 by Job's plot method and, the binding constants were calculated as 1.6638 × 1010 and 9.22929 × 108 M-1, respectively. Compound LH exhibited OR and XOR logic gate behavior with H+, Fe2+, and Cu2+ as inputs. Further, the compound LH and bovine serum albumin binding interaction showed quenching of fluorescence by Förster resonance energy-transfer mechanism.

Economical synthesis of silver nanoparticles using leaf extract of Acalypha hispida and its application in the detection of Mn(II) ions.

This study was focused on the synthesis of silver nanoparticles using Acalypha hispida leaf extract and the characterization of the particles using UV-Vis spectroscopy, XRD, FT-IR, and TEM. The results showed the formation of silver nanoparticles, crystalline in nature, with an average size of 20-50 nm. The leaf extract components were analyzed with GC-MS and exhibited a high content of Phytol (40.52%), n-Hexadecanoic acid (9.67%), 1,2,3-Benzenetriol (7.04%), α-d-Mannofuranoside methyl (6.22%), and d-Allose (4.45%). The optimization and statistical investigation of reaction parameters were studied and maximum yield with suitable properties of silver nanoparticles was obtained at leaf extract volume (0.5 mL), the concentration of silver nitrate (1.75 mM), and reaction temperature (50 °C). The method of detecting Mn2+ ions using the colloidal silver nanoparticles was discussed. The minimum and maximum detection limit were found to be 50 and 200 µM of Mn(II) ions, respectively. Thus, the obtained results encourage the use of economical synthesis of silver nanoparticles in the development of nanosensors to detect the pollutants present in industrial effluents.

Thermo-chemo-sonic pre-digestion of waste activated sludge for yeast cultivation to extract lipids for biodiesel production.

The low cost biosynthesis of microbial lipids are an efficient feedstock to replace plant based oil for biodiesel production. The present study objective is to explore the effect of thermo-chemo-sonic pre-digestion of municipal Waste Activated Sludge (WAS) to cultivate oleaginous L. starkeyi MTCC-1400 as a model organism to produce high yield biomass and lipid. Higher Suspended Solids (SS) reduction (20 and 15.71%) and Chemical Oxygen Demand (COD) solubilization (27.6 and 22.3%) were achieved at a Specific Energy (SE) input of 5569 kJ/kg for WAS digested with NaOH and KOH, respectively. The maximum biomass of 17.52 g L-1 and lipid 64.3% dwt were attained in NaOH pre-digested sample. The analyzed lipid profile exhibited high content of palmitic acid (45.6%) and oleic acid (38.7%) which are more suitable for biofuel production. Thus, these results strongly motivate the use of pre-digested WAS as an efficient and economical substrate for biodiesel production.

Design, Synthesis, Spectral Analysis, In Vitro Anticancer Evaluation and Molecular Docking Studies of Some Fluorescent 4-Amino-2, 3-Dimethyl-1-Phenyl-3-Pyrazolin-5-One, Ampyrone Derivatives.

The commenced work deals with the synthesis, characterization and evaluation of biological activities of 4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one. The synthesis was done by the condensation of aromatic acid chlorides with 4-aminoantipyrine. The structures of synthesized derivatives were elucidated using IR, Mass, 1H NMR and 13C NMR spectroscopy, and their UV-Visible and fluorescence properties were studied. The compounds showed significant dual fluorescence. Molecular docking was used to understand the small molecule-receptor protein interaction. The derivatives were screened for their in vitro cytotoxic activity against the reference drug pazopanib on human cervical cancer cell line (SiHa) using MTT assay.

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

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

Biomass production of multipopulation microalgae in open air pond for biofuel potential.

Biodiesel gains attention as it is made from renewable resources and has considerable environmental benefits. The present investigation has focused on large scale cultivation of multipopulation microalgae in open air pond using natural sea water without any additional nutritive supplements for low cost biomass production as a possible source of biofuel in large scale. Open air algal pond attained average chlorophyll concentration of 11.01 µg/L with the maximum of 43.65 µg/L as well as a higher lipid concentration of 18% (w/w) with lipid content 9.3 mg/L on the 10th day of the culture; and maximum biomass of 0.36 g/L on the 7th day of the culture. Composition analysis of fatty acid methyl ester (FAME) was performed by gas chromatography and mass spectrometry (GCMS). Multipopulation of algal biomass had 18% of total lipid content with 55% of total saturated fatty acids (SFA), 35.3% of monounsaturated fatty acids (MUFA) and 9.7% of polyunsaturated fatty acids (PUFA), revealing a potential source of biofuel production at low cost.

Synthesis and spectroscopic characterization of fluorescent 4-aminoantipyrine analogues: Molecular docking and in vitro cytotoxicity studies.

Two substituted aromatic carbonyl compounds (compounds 1 and 2) of 4-aminoantipyrine were synthesized by condensation of fluorine substituted benzoyl chlorides and 4-aminoantipyrine. The structures of synthesized derivatives were established on the basis of UV-Vis, IR, and Mass, (1)H, (13)C NMR and Fluorescence spectroscopy. Both compounds showed significant fluorescence emission and two broad emission bands were observed in the region at 340 nm and 450 nm on excitation at 280 nm. Theoretically to prove that the molecule has anticancer activity against cervical cancer cells, the compounds were analyzed for molecular docking interactions with HPV16-E7 target protein by Glide protocol. Furthermore, 4-aminoantipyrine derivatives were evaluated for their in vitro cytotoxic activity against human cervical cancer cells (SiHa) by MTT assay. Compound 1 showed two fold higher activity (IC50=0.912 µM) over compound 2, and its activity was similar to that of Pazopanib, suggesting that although the two compounds were chemically very similar the difference in substituent on the phenyl moiety caused changes in properties.

Pseudotumour of the Mandible Associated with von Willebrand's Disease.

Patients with bleeding disorders may occasionally present with pseudotumours. Most commonly these occur in the soft tissues and long bones, and are very rare in the maxillofacial region. We present the clinical details and management of a pseudotumour of the mandible in a 12-year-old girl with von Willebrand's disease.

Thermal performance of ethylene glycol based nanofluids in an electronic heat sink.

Heat transfer in electronic devices such as micro processors and power converters is much essential to keep these devices cool for the better functioning of the systems. Air cooled heat sinks are not able to remove the high heat flux produced by the today's electronic components. Liquids work better than air in removing heat. Thermal conductivity which is the most essential property of any heat transfer fluid can be enhanced by adding nano scale solid particles which possess higher thermal conductivity than the liquids. In this work the convective heat transfer and pressure drop characteristics of the water/ethylene glycol mixture based nanofluids consisting of Al2O3, CuO nanoparticles with a volume concentration of 0.1% are studied experimentally in a rectangular channel heat sink. The nano particles are characterized using Scanning Electron Microscope and the nannofluids are prepared by using an ultrasonic vibrator and Sodium Lauryl Salt surfactant. The experimental results showed that nanofluids of 0.1% volume concentration give higher convective heat transfer coefficient values than the plain water/ethylene glycol mixture which is prepared in the volume ratio of 70:30. There is no much penalty in the pressure drop values due to the inclusion of nano particles in the water/ethylene glycol mixture.

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

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

Ethyl 2-(7-oxo-3,5-diphenyl-1,4-diaze-pan-2-yl)acetate.

In the title compound, C(21)H(24)N(2)O(3), the diazepane ring adopts a chair conformation. The central diazepane ring forms dihedral angles 67.80 (7) and 72.29 (5)° with the two benzene rings. The eth-oxy-carbonyl group is disordered over two conformations with site-occupancy factors of 0.643 (5) and 0.357 (5). In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R(2) (2)(8) loops.

Ethyl 7-oxo-3,5-diphenyl-1,4-diazepane-2-carboxyl-ate.

The title compound, C(20)H(22)N(2)O(3), crystallizes with two independent mol-ecules in the asymmetric unit. In both mol-ecules, the diazepane rings adopt chair conformations. The mean planes of the diazepane rings in the two molecules form dihedral angles of 71.6 (4)/40.3 (5) and 75.9 (5)/58.6 (7)° with the neighbouring benzene rings. The carbonyl-group O atoms deviate significantly from the diazepane rings, by 0.685 (14) and 0.498 (13) Å. The eth-oxy-carbonyl groups show conformational difference between two mol-ecules, as reflected in the orientation of the carbonyl O atoms and the C-C-O-C torsion angle of -179.0 (2)° in one mol-ecule and 73.2 (2)° in the other. In one molecule there is a short N-H⋯O contact that generates an S(5) ring motif. In the crystal, N-H⋯O inter-actions generate R(2) (2)(8) graph-set motifs and C-H⋯O inter-actions generate R(2) (2)(10) and R(2) (2)(14) graph-set motifs. C-H⋯π inter-actions also occur.