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Candida albicans infections are widespread in people and cause cutaneous and systemic infections. Optimisation of garlic mustard oil macerate (GMM) based on antifungal activity against C. albicans was done using agar diffusion method. Upon vapour diffusion assay, the volatile organic compounds of both GMM and MO were found to eradicate C. albicans . During agar diffusion, MO did not inhibit fungal growth, while undiluted GMM oil demonstrated a 26.33 ± 0.33 mm zone of inhibition. The minimum inhibitory concentration and minimum fungicidal concentration against C. albicans were 12.5%, v/v of GMM oil and 25%, v/v of GMM oil, respectively. Scanning electron microscopy analysis showed cell membrane disintegration of fungal cells by 50%, v/v of GMM oil, and MO caused no cell wall damage. In-silico analysis revealed strong binding affinity of sinigrin, ajoene, dithiin with N-myristoyltransferase. In conclusion, the optimised GMM preparation can be a potential antifungal agent against tropical C. albicans infections.

The antibacterial activity of silver nanoparticles and rhamnolipid are well known individually. In the present research, antibacterial and chemotactic activity due to colloidal silver nanoparticles (SNP), rhamnolipid (RL) and silver nanoparticles/rhamnolipid composite (SNPRL) were evaluated using Staphylococcus aureus (MTCC3160), Escherichia coli (MTCC40), Pseudomonas aeruginosa (MTCC8163) and Bacillus subtilis (MTCC441) as test strains. Further, the SNPRL nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The observation clearly indicates that SNPRL shows prominent antibacterial and chemotactic activity in comparison to all of its individual precursor components., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Alpha-amylase was immobilized onto polyaniline-polyvinyl alcohol (PAni-PVA) film by cross linking with glutaraldehyde. The activity yield and immobilization efficiency was calculated as 13.58% and 30.60% respectively. The PAni-PVA-Amylase films were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and amylase activity assay. The immobilized α-amylase had its optimum activity at pH 7.0 and 25°C. The immobilization of α-amylase onto the PAni-PVA films protected the enzyme from Fe(2+) inhibition. The PAni-PVA-Amylase films could be used effectively for 30 cycles with 60% retention of the activity., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Rhamnolipid (RL) from Pseudomonas aeruginosa was dissolved in distilled water with concentration equivalent to its critical micelle concentration (CMC). Silver nanoparticles (SNP) synthesized in the RL colloid were found to be stable for more than 1 month. Further, after 1 month when the SNP in RL colloid (SNPRL) were exposed to NaCl solution it took about 60 mg/ml as compared to 2 mg NaCl/ml in the case of SNP colloid for degrading silver nanoparticles. The inference suggests that the RL must undergo vesicle formation and to prevent silver nanoparticle exposure to NaCl., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In the present study, the interaction of rhamnolipid produced by Pseudomonas aeruginosa OBP1 with the cell surfaces of Staphylococcus aureus (MTCC 3160) and Klebsiella pneumoniae (MTCC 618) were studied. Rhamnolipid concentration below critical micelle concentration (CMC) did not exhibit significant antibacterial activity. However, on increasing rhamnolipid concentration beyond CMC a prominent antibacterial activity was observed. The results demonstrated different degree of rhamnolipid interaction with both the bacteria. This might be due to the changes in their cell wall composition. The antibacterial activity determined by minimum inhibitory concentration (MIC). The antibacterial activity is prominent within 30 min of incubation. The antibacterial property of rhamnolipid was effective in all tested pH levels (5-9). The rhamnolipid was effective in almost all tested pH levels and showed better chemoattractant property against both the tested bacteria in comparison to glucose. The increase in the membrane permeability was evidenced by increase in the release of protein, enhancement in cell surface hydrophobicity and raises in the retention of crystal violet dye. Further, leakage of 260 nm absorbing intracellular materials, fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis confirmed the disruptive action of rhamnolipid. The above evidences support the idea that rhamnolipid significantly alters the cell membrane/envelop that leads to cell damage and enhances membrane permeability. Such activity of rhamnolipid could be used as an additive in the formulation of antibiotic and other antimicrobial agents for enhancing the effectiveness of chemotherapeutics., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Five polyphenolic compounds were isolated from four aroid species [using High Performance Liquid Chromatography (HPLC)] and identified using Fourier Transform Infrared (FTIR) spectroscopy and Nuclear Magnetic Resonance (NMR) analysis. The compounds benzoic acid, caffeic acid, coumaric acid, ferulic acid and syringic acids were immobilized on magnetic nanoparticles (MNPs) using poly(ethylene glycol) (PEG) as linker polymer. The obtained PEG-MNP-polyphenol trios were characterized using transmission electron microscopy (TEM) and FTIR. Their biochemical characterization were done to find out the DPPH scavenging capacity and amount of polyphenol loaded (galic acid equivalent) in each type of MNP-polyphenol trio. To know the antioxidant activity the MNP-polyphenol trios were subjected to H(2)O(2) induced haemolysis prevention assay and syringic acid trio was found to most potent. To ensure that the MNP-polyphenol trios were magnetically active the hysteresis loop analysis was also done., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Knowing keratin is the main component and mechanical strength of hair a study was performed to evaluate whether Dillenia indica seed sap can affect molecular strength of hair or not. In the present study the human hair collected from barber shop waste were subjected to purified sap for 12 h and then analysed using Fourier transform infrared spectroscopy (FTIR) for documenting evidence for keratin degradation. Further the deterioration was confirmed by thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM)., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Cellulose from Musa balbisiana was purified. A part of it was dispersed in distilled water using ultrasonication. The silver nanoparticles (SNP) were synthesized in the colloidal cellulose solution and stability of the nanoparticles was tested using UV-Vis spectrophotometer. Further characterization of the composite was done using spectral analysis by Fourier Transform Infrared Spectroscopy (FTIR) to reveal any bond formation between silver nanoparticles with M. balbisiana cellulose. Here we found that cellulose/silver nanoparticle colloid is stable for 29 days and there is no chemical interaction of cellulose with silver nanoparticles., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In the present research we have defined a novel green method of silver nanoparticles synthesis using Dillenia indica fruit extract. D. indica is an edible fruit widely distributed in the foothills of Himalayas and known for its antioxidant and further predicted for cancer preventive potency. The maximum absorbance of the colloidal silver nanoparticle solution was observed at 421 nm when examined with UV-vis spectrophotometer., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Polyhydroxyalkanoates (PHAs) are naturally occurring polyesters synthesized by bacteria for carbon and energy storage and it has commercial potential as bioplastic. The bacterial species Bacillus circulans MTCC 8167, isolated from crude oil contaminated soil, can efficiently produce medium chain length polyhydroxyalkanoates (P-3HB-co-3HV) from cheap carbon sources like dextrose. The molecular mass of P-3HB-co-3HV was reported as 5.1×10(4)Da with polydispersity index of 1.21 by gel permeation chromatography. In the present investigation different bacteria and fungi species were used for testing the biodegradability of the extracted polymer. The FTIR spectra of the biodegraded PHBV film showed a decrease in the peak from 1735 cm(-1) (untreated film) to 1675 cm(-1), and disappearance of a peak present in the control at 2922 cm(-1) indicating the breakdown of ester (>C=O) or O-R group and -C=H bond, respectively. From biodegradability testing, the tested microorganisms were found to have decisive contribution to the biodegradation of P-3HB-co-3HV polymer., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Polyhydroxyalkanoate (PHA) was produced by growing Bacillus circulans (MTCC 8167) in the specific detection medium. The identification of the polymer as PHA was confirmed by fluorescence microscopy. The PHA was purified and characterized using FT-IR. The silver nanoparticles (SNP) were synthesized from AgNO3 in the dispersed colloids of PHA (0.085%) using NaBH4 (sodium borohydrate as reducing agent). The stability was tested using wave length scanning with a UV-Vis spectrophotometer and finally with transmission electron microscopy. The PHA stabilized solution was found to be stable for 30 days as against the low stability of silver nanoparticles (SNP) solution alone., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Research on curcumin (polyphenol derived from the rhizome of herb Curcuma longa) has occupied a unique niche owing to its distinctive properties, unique molecular architecture and multi-potent efficacies, particularly in the bio-medical domain with recent interest in material science. In the present study, conjugation of curcumin onto biocompatible poly(ethylene glycol)--templated magnetic iron oxide nanoparticles (MNP) (2-5 nm), prepared through a simple wet chemical route is reported along with modulation of the activity of the partners. Statistical optimization, using response surface methodology, of sonication parameters (8 min, 0.4 cycle and 60% amplitude) for maximal curcumin loading (86%), has shown major morphology directing effect generating triads, tetrads, amongst others and chain-like arrangement (TEM imaging) of the bio-conjugated nanoparticles (80-90 nm). Intonation of the magnetometric parameters of the PEG assisted MNPs on bioconjugation was also evident. The synergistic potency of the partners, the polymer templated iron oxide nanoparticles and curcumin, was unmasked during scavenging of diphenyl picryl hydrazyl (DPPH). The system represents an architecturally appealing, magnetically responsive bio-conjugated system possessing synergistic participation of the partners, with prospective applications in medical domain., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Starch/polyaniline composites have been synthesized using oxidative polymerization of polyaniline in an aqueous dispersion of starch isolated from Colocasia esculenta corm. Scanning electron micrographs reveals the growth of polyaniline over the surface of the starch granules. DPPH scavenging and haemolysis prevention assay have been performed to estimate the antioxidant activity and cytotoxicity of the composites. Formation of new properties of the composites as compared to starch and poloyaniline was evident from the X-ray diffraction analysis (XRD). Characterization done using UV-Vis, FTIR and DSC analysis provide evidence of composite formation. Composite possesses antioxidant nature which increases with the concentration of polyaniline. The haemolysis prevention activity of these novel composite materials is found to increase as compared to the pure polyaniline with minor compromise in the antioxidant activity. The materials show tremendous potential for biomedical applications., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

The present work is a modification for Serpen et al.'s method for antioxidant activity determination for insoluble materials with special reference to metal oxide nanoparticles. As reported in our former publications the mixing procedures were followed as mentioned by Serpen et al. A new mixing procedure was followed for enhancing the reaction between metal oxide nanoparticles and DPPH in the solution. The sonication inside a water bath enhances the DPPH scavenging capacity of metal oxide nanoparticles up to 13.94% and 18.96% in case of ferric oxide and nickel oxide nanoparticles respectively. The control DPPH solution without any nanoparticles does not show any degradation due to sonication., (Copyright 2010 Elsevier B.V. All rights reserved.)

We investigated a novel inorganic (nickel oxide) nanoparticles as a potential antioxidant in the biosystems. The particles were synthesized using self-propagating high-temperature synthesis (SHS) method at 650 degrees C. The antioxidant property of the nickel oxide particles was investigated in an in vitro system, using modified DPPH method for insoluble solid materials., (Copyright 2010 Elsevier B.V. All rights reserved.)

Polyaniline (PAni) nanofibers doped with HCl and CSA have been irradiated with 90 MeV O(7+) ions with fluence of 3 x 10(10), 3 x 10(11) and 1 x 10(12) ions cm(-2). TEM micrographs show a decrease in the fiber diameter with increasing irradiation fluence, which has been explained on the basis of the Coulomb explosion model. XRD analysis reveals a decrease in the crystalline domain length and an increase in the strain. The increase in d-spacing for the (100) reflection with increasing irradiation fluence is ascribed to the increase in the tilt angle of the polymer chain, which is also evident from micro-Raman spectra. UV-vis spectra of the PAni nanofibers exhibit blue-shift in the absorption bands attributed to pi-pi* band transitions indicating a reduction in particle size after SHI irradiation; as also observed in TEM micrographs. Micro-Raman spectra also reveal a transition from the benzenoid to quinoid structures in the PAni chain as the fluence is increased. Although the quinoid unit has no hydrogen for DPPH scavenging, the antioxidant activity of PAni nanofibers is found to increase with increasing fluence. This has been attributed to the availability of more reaction sites as a result of fragmentation of the PAni nanofibers which compensates for the benzenoid to quinoid transition after irradiation. The biocompatibility of the PAni nanofibers is also found to increase with increasing irradiation fluence, indicating the possibility of employing swift heavy ion irradiation as an effective technique in order to modify conducting polymer nanostructures for biomedical applications.

Polyaniline (PAni) nanofibers have been synthesized by interfacial polymerization using hydrochloric acid (HCl) and camphor sulfonic acid (CSA) as dopants. The powder x-ray diffraction pattern of bulk polyaniline reveals ES I structure and has been indexed in a pseudo-orthorhombic lattice. The broadening of (110) reflection in the nanofiber samples has been analysed in terms of domain length and strain using a convolution method employing a Voigt function. The increase in d spacing for the (110) reflection in HCl-doped PAni nanofibers have been assigned to the change in structural conformation due to the increase in the tilt angle of the polymer chain, which is also evident from microRaman spectra. UV-vis spectra of the PAni nanofibers exhibit a remarkable blueshift in the absorption bands attributed to pi-pi* and pi-polaron band transitions indicating a reduction in particle size, which is also observed in TEM micrographs. The antioxidant activity of the polyaniline nanofiber samples has been investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay by employing UV-visible spectroscopy. It has also been observed that polyaniline nanofibers are able to protect the haemolysis of red blood cells (RBCs) from cytotoxic agents, namely H(2)O(2). The observed enhancement in the antioxidant and haemolysis prevention activity of the PAni nanofibers as compared to bulk has been attributed to the reduction in particle size and changes in structural conformation, as evident from TEM, XRD and microRaman spectroscopy.

Epoxy modified Mesua ferrea L. seed oil (MFLSO) based polyurethane nanocomposites with different weight % of clay loadings (1%, 2.5% and 5%) have been evaluated as biocompatible materials. The nanocomposites were prepared by ex situ solution technique under high mechanical shearing and ultrasonication at room temperature. The partially exfoliated nanocomposites were characterized by Fourier transform infra-red (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The mechanical properties such as tensile strength and scratch hardness were improved 2 and 5 times, respectively by nanocomposites formation. Even the impact resistance improved a little. The thermostability of the nanocomposites was enhanced by about 40 degrees C. Biodegradation study confirmed 5-10 fold increase in biodegradation rate for the nanocomposites compared to the pristine polymers. All the nanocomposites showed non-cytotoxicity as evident from RBC hemolysis inhibition observed in anti-hemolytic assay carried over the sterilized films. The study reveals that the epoxy modified MFLSO based polyurethane nanocomposites deserve the potential to be applicable as biomaterials.