Antimicrobial activity of sesquiterpene lactones isolated from traditional medicinal plant, Costus speciosus (Koen ex.Retz.) Sm

<p>Abstract</p> <p>Background</p> <p><it>Costus speciosus </it>(Koen ex.Retz.) Sm (Costaceae) is an Indian ornamental plant which has long been used medicinally in traditional systems of medicine. The plant has been found to possess diverse pharmacological activities. Rhizomes are used to treat pneumonia, rheumatism, dropsy, urinary diseases, jaundice, skin diseases and leaves are used<b/>to treat mental disorders.</p> <p>Method</p> <p>Antibacterial and antifungal activities were tested using Disc diffusion method and Minimum Inhibitory <b>Concentration </b>(MIC). Column chromatography was used to isolate compounds from hexane extract. X-ray crystallography technique and GC-MS analysis were used to identify the compounds</p> <p>Results</p> <p>Antibacterial and antifungal activities were observed in hexane, chloroform, ethyl acetate and methanol extracts. Hexane extract of <it>C.speciosus </it>showed good activity against tested fungi also. Two sesquiterpenoid compounds were isolated (costunolide and eremanthin) from the hexane extract. Both the compounds did not inhibit the growth of tested bacteria. But, both the compounds inhibited the tested fungi. The compound costunolide showed significant antifungal activity. The MIC values of costunolide were; 62.5 μg/ml against <it>Trichophyton mentagrophytes</it>, 62. μg/ml against <it>T. simii</it>, 31.25 μg/ml against <it>T. rubrum </it>296, 62.5 μg/ml against <it>T. rubrum </it>57, 125 μg/ml against <it>Epidermophyton floccosum</it>, 250 μg/ml against <it>Scopulariopsis </it>sp, 250 μg/ml against <it>Aspergillus niger</it>, 125 μg/ml against <it>Curvulari lunata</it>, 250 μg/ml against <it>Magnaporthe grisea</it>.</p> <p>Conclusion</p> <p>Hexane extract showed promising antibacterial and antifungal activity. The isolated compound costunolide showed good antifungal activity.</p

Microfluidic Synthesis of Microfibers for Magnetic-Responsive Controlled Drug Release and Cell Culture

This study demonstrated the fabrication of alginate microfibers using a modular microfluidic system for magnetic-responsive controlled drug release and cell culture. A novel two-dimensional fluid-focusing technique with multi-inlets and junctions was used to spatiotemporally control the continuous laminar flow of alginate solutions. The diameter of the manufactured microfibers, which ranged from 211 µm to 364 µm, could be well controlled by changing the flow rate of the continuous phase. While the model drug, diclofenac, was encapsulated into microfibers, the drug release profile exhibited the characteristic of a proper and steady release. Furthermore, the diclofenac release kinetics from the magnetic iron oxide-loaded microfibers could be controlled externally, allowing for a rapid drug release by applying a magnetic force. In addition, the successful culture of glioblastoma multiforme cells in the microfibers demonstrated a good structural integrity and environment to grow cells that could be applied in drug screening for targeting cancer cells. The proposed microfluidic system has the advantages of ease of fabrication, simplicity, and a fast and low-cost process that is capable of generating functional microfibers with the potential for biomedical applications, such as drug controlled release and cell culture

An experimental study on hulk and solution polymerization of methyl methacrylate with responses to step changes in temperature

Several important polymerizations [e.g., polymethylmethacrylate (PMMA), polystyrene (PS), etc.] exhibit the gel, glass and cage effects during polymerization. These are associated with the decrease of the diffusivities of the macroradicals, monomer molecules and primary radicals with increasing viscosities of the reaction mass. The recent model of Seth and Gupta [ V. Seth, S.K. Gupta, J. Polym. Eng., 15 (1995) 283.] has been used to explain these results. The model parameters are tuned using experimental data on near-isothermal bulk and solution polymerizations of methyl methacrylate (MMA) in a 1-1 stainless steel, computer controlled reactor. A series of bulk and solution polymerizations (at 10%, 20% and 30% solvent concentrations) have been carried out at two different temperatures (50 degrees C and 70 degrees C) using benzoyl peroxide (BPO) as initiator at one initiator concentration (41.5 mol/m(3)). Two important process variables, e.g., monomer conversion and viscosity average molecular weights were measured using gravimetric analysis and dilute solution viscometry, respectively. The results obtained from this study are in excellent agreement with those reported earlier in the literature. Experiments have also been carried out with step changes in temperature. Thus, the present study establishes the applicability of the model for the more general non-isothermal reactor operations with bulk as well as solution polymerizations along with semi-batch reactor operations. (C) 1998 Elsevier Science.

Advances in liposomal drug delivery to cancer: An overview

Liposomes are biodegradable and biocompatible lipid bilayer vesicles which are widely exploited as preferred carriers for smart delivery of both hydrophobic as well as hydrophilic bioactives. Structural fabrication of liposomes for ligand anchoring, long-circulation and stimuli-responsiveness are advancing features to meet the needs of clinical and industrial demands. Recent studies report newer developments in multipronged liposomes for synchronized theranostic manifestations in cancer treatment. This review gives an insight to advances in ligand targeted liposomes (like folate, mannose, transferrin, hyaluronic acid, antibody, aptamer, and peptide, etc.), stimuli-triggered liposomes (stimuli such as pH, temperature, and hypoxia, etc.) and liposomes mediated autophagy modulation, and theranostic liposomes for the diagnosis and treatment of cancer. It also includes patents, clinical studies and marketed liposomal products. This assemblage of advances would be of great interest to budding scientists and pharmaceutical companies engaged in the development of liposomes