The significance of complex polysaccharides in personal care formulations

Complex polysaccharides have numerous pharmacological activities, such as antioxidant, antibacterial, antiviral, immunomodulating, anticoagulant and anticancer effects. In personal care products, these biopolymers are used as thickener and stabilizing agents or as moisturizing ingredients that could be beneficial to the skin. Various polysaccharides, such as glycosaminoglycans (GAGs), hyaluronic acid (HA), carrageenan, fucose, fucoidan, chitin, chitosan, etc., have applications in cosmeceutical industries. GAGs and HA incorporated in moisturizing creams strengthen the skin barrier by forming a protective layer which prevents transdermal water loss. Therefore, these polysaccharides have been formulated into potential cosmeceuticals and biopharmaceuticals.     

Study of tolbutamide-hydroxypropyl-gamma-cyclodextrin interaction in solution and solid state

Tolbutamide-hydroxypropyl-gamma-cyclodextrin (TBM-HPGCD) interaction has been investigated in an aqueous environment and in the solid state. The solubility of TBM was increased in accord with the amount of HPGCD added to the aqueous medium forming a soluble inclusion compound. The phase solubility diagram obtained was of A(L) type. Physical mixtures and kneaded systems of the drug and cyclodextrin derivative were prepared in 1:1 and 1:2 drug/cyclodextrin mol/mol ratio. All solid binary systems were characterised by hot-stage microscopy (HSM), differential scanning calorimetry (DSC), thermogravimetry (TG) and X-ray powder diffractometry (XRD). An inclusion complex was formed in both of the kneaded systems. In the 1:2 kneaded system, the entire drug was included in the cyclodextrin cavity, while, in the 1:1 kneaded system only a part of the drug formed an inclusion complex with the cyclodextrin. A significant improvement in the dissolution of the drug was obtained from the kneaded systems in comparison with that of the pure TBM and physical mixtures. However, there was no significant difference between the dissolution profiles of the two kneaded systems. The study suggests that an inclusion complex was obtained both in aqueous solution and in solid state.     

The electrodeposition of indium onto vitreous carbon from acidic chloride media

Cyclic voltammetry and potential step techniques have been used to study the electrodeposition of indium metal from 1 mol dm^?3 potassium chloride, pH 2–4.5, onto a vitreous carbon electrode. It is confirmed that the In/In³⁺ couple is fast in chloride media and the nucleation and growth of the indium phase is discussed. It is shown that instantaneous nucleation occurs at an overpotential of only a few mV and that the growth of the nuclei is three dimensional.     

Colorizing mechanism of brass surface by femtosecond laser induced microstructures

In this paper, we exhibit the colorizing of brass surfaces by forming femtosecond laser induced microstructures on the sample surfaces. A variety of single colors such as brown, yellow, green, and black are introduced on brass surfaces by engineering periodic microgratings, microholes, and ring-shaped micro-patterns using Single Beam Direct Laser Writing (SBDLW) technique. The color of the micro-structured brass surfaces is certainly dependent on the width, depth, and period of the microstructures. Finally, we explain, in brief, the colorizing mechanism of metals by femtosecond laser induced microstructures.     

Green synthesis and characterizations of Nickel oxide nanoparticles using leaf extract of Rhamnus virgata and their potential biological applications

In the present report, Nickel oxide nanoparticles (NiONPs) were synthesized using Rhamnus virgata (Roxb.) (Family: Rhamnaceae) as a potential stabilizing, reducing and chelating agent. The formation, morphology, structure and other physicochemical properties of resulting NiONPs were characterized by Ultra violet spectroscopy, X‐ray diffraction (XRD), Fourier Transform Infrared analysis (FTIR), Scanning electron microscopy (SEM), Energy‐dispersive‐spectroscopy (EDS), Transmission electron microscopy (TEM), Raman spectroscopy and dynamic light scattering (DLS). Detailed in vitro biological activities revealed significant therapeutic potential for NiONPs. The antimicrobial efficacy of biogenic NiONPs was demonstrated against five different gram positive and gram negative bacterial strains. Klebsiella pneumoniae and Pseudomonas aeruginosa (MIC: 125 μg/mL) were found to be the least susceptible and Bacillus subtilis (MIC: 31.25 μg/mL) was found to be the most susceptible strain to NiONPs. Biogenic NiONPs were reported to be highly potent against HepG2 cells (IC₅₀: 29.68 μg/ml). Moderate antileishmanial activity against Leishmania tropica (KMH₂₃) promastigotes (IC₅₀: 10.62 μg/ml) and amastigotes (IC₅₀: 27.58 μg/ml) cultures are reported. The cytotoxic activity was studied using brine shrimps and their IC₅₀ value was recorded as 43.73 μg/ml. For toxicological assessment, NiONPs were found compatible towards human RBCs (IC₅₀: > 200 μg/ml) and macrophages (IC₅₀: > 200 μg/ml), deeming particles safe for various applications in nanomedicines. Moderate antioxidant activities: total antioxidant capacity (TAC) (51.43%), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) activity (70.36%) and total reducing power (TRP) (45%) are reported for NiONPs. In addition, protein kinase and alpha amylase inhibition assays were also performed. Our results concluded that Rhamnus virgata synthesized NiONPs could find important biomedical applications with low cytotoxicity to normal cells.     

Synthetic approaches toward stilbenes and their related structures

Compounds belonging to the stilbene family have gained remarkable significance in pharmaceutical as well as material chemistry. The current review covers the various synthetic approaches for the syntheses of stilbene scaffold and related structures over last 30 years. In addition, this review also highlights the role of stilbene intermediates used in the synthesis of important molecules with diverse applications in the field of pharmaceutics and material science.     

Experimental comparison of performance and emission characteristics of 4-stroke CI engine operated with Roselle and Jatropha biodiesel blends

The environmental degradation, combined with the continuous depletion of the world's fossil fuel reserves, has forced the search for alternative fuels. This study was performed to investigate the performance of novel biodiesels in the CI engine. The experiments were performed at three different compressions ratios (16:1, 17:1, 18:1) and four loading conditions (25%, 50%, 75%, 100%). Different types of fuels such as jatropha biodiesel (JB), roselle biodiesel (RB), and ternary biodiesel (TB) were prepared and analyzed. The thermal performance of different fuels was analyzed in terms of brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), and exhaust gas temperature (EGT). The emission characteristics such as CO₂ emission, NO_x emission, and smoke emission were analyzed for all types of fuels. The results of these fuels in the engine were compared with mineral diesel (MD). The BTE was increased with increasing compression ratios and loads for all types of fuels. The BSFC was increased with increasing compression ratios but decreased with increasing loads. The increase in emission of NO_x was observed at higher compression ratios and loads. However, the CO₂ emission was decreased at higher loads and lower compression ratio. The performance curves achieved with a 20% jatropha biodiesel blend showed results that were approximate to those obtained with pure MD. The comparative analysis between different fuels showed that JB exhibit higher thermal performance as compared to other biodiesels. Therefore, JB can be a better alternative to conventional fuel.