Biodegradable implants have shown great promise for the repair of bone defects and have been commonly used as bone substitutes, which traditionally would be treated using metallic implants. The need for a second surgery exacerbated by the stress shielding effect caused by an implant has led researchers to consider more effective, synthetic biodegradable graft substitutes. The hierarchical structures commonly designed are inspired by nature in human bones, which consist of minerals such as hydroxyapatite, a form of calcium phosphate and protein fiber. The bone graft bio-substitutes should possess a combination of properties for the purpose of facilitating cell growth and adhesion, a high degree of porosity, which would facilitate the transfer of nutrients and excretion of the waste products, and the scaffold should have high tensile strength and high toughness in order to be consistent with human tissues. Blending of polycaprolactone and hydroxyapatite has demonstrated great potential as bone substitutes. It is essential to identify a standardized processing methodology for the composite, which would result in optimum mechanical property for the biocomposite. In this study, biocomposites made of polycaprolactone (PCL) and hydroxyapatite (HAP) are reviewed for their applications in bone tissue engineering. The processing methodologies are discussed for the purpose of obtaining the porosity and pore size required in an ideal tissue scaffold. The properties of the composite can be varied based on the change in pore size, porosity, and processing methodology. This paper reviews and evaluates the methods to produce the hydroxyapatite-polycaprolactone scaffolds.

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in Wiley Online Library (wileyonlinelibrary.com).Thiazole and related nucleus are one of the most important potential entities in the largely growing chemical world of heterocyclic compounds exhibiting remarkable pharmacological activities. The knowledge of various synthetic pathways and diverse physicochemical parameters of such compounds draw the especial attention of medicinal chemists to produce combinatorial library and carry out exhaustive efforts in the search of lead molecules. The similar compounds synthesized through different routes bear variable magnitudes of biological activities. The present review highlights a broad view on biological activities of compounds having thiazole nucleus.

Plastic materials, particularly polyethylene, are the potential source of environmental pollution. In the present study, a fungal strain was isolated from plastic waste dumpsites capable of adhering to high-density polyethylene (HDPE) surface. The fungal strain was identified as Aspergillus niger (ITCC no. 6052). A visible increase in the growth of the fungi was observed on the surface of the polyethylene when cultured in minimal medium at 30 • C and 120 rpm, for 1 month. Approximately 3.44% reduction (gravimetrically) in mass and 61% reduction in tensile strength of polyethylene was observed after 1 month of incubation with fungal isolate. Scanning electron microscope analysis showed hyphael penetration and cracks on the surface of polyethylene. A thick network of fungal hyphae forming a biofilm was also observed on the surface of the plastic pieces. The efficient biofilm formation on polyethylene surface by Aspergillus niger (ITCC no. 6052) is attributed to its high cell surface hydrophobicity. This study indicated that Aspergillus niger (ITCC no. 6052) has ability to degrade thermally oxidized polyethylene.