Fabrication and characterization of chicken feather keratin/polysaccharides blended polymer coated nonwoven dressing materials for wound healing applications.

In this research work, three kinds of nonwoven wound dressings were developed from chicken feather keratin (CFK-NW), keratin­sodium alginate (CFK-SA-NW) and keratin-chitosan (CFK-CS-NW) and characterized using FTIR and SEM. The physical characteristics such as air permeability, thickness and areal density test results revealed the suitability of fabricated materials for wound dressing applications. CFK-SA-NW and CFK-CS-NW indicated a positive antibacterial effect against Gram's positive Staphylococcus aureus and Gram's negative Klebsiella pneumoniae and Escherichia coli bacteria with the zone of inhibition enhanced over >2.0 cm. Moreover, the biomedical potentials of dressing materials has been investigated by cell viability and cytotoxicity tests. Further, the wound healing ability was demonstrated using in vivo model (Albino Wistar rat). The fabricated materials exhibited good support for cell viability and a strong cytocompatibility. Furthermore, the hundred percent wound healing ability of CFK-CS-NW, CFK-SA-NW, CFK-NW and untreated control rats was observed at 15, 17, 21 and 23 days, respectively, Moreover, the wound healing potential of CFK-CS-NW and CFK-SA-NW was found to be better than that of CFK-NW and control group of rats. The outcome of the present study discloses the prospective applications of the developed materials as wound dressing biomaterial.

A study on medium chain length-polyhydroxyalkanoate accumulation in Escherichia coli harbouring phaC1 gene of indigenous Pseudomonas sp. LDC-5.

AIMS: This study is mainly focused on the heterologous expression and accumulation of polyhydroxyalkanoates (PHA) in Escherichia coli. METHODS AND RESULTS: PHA synthase gene (phaC1) from indigenous Pseudomonas sp. LDC-5 was amplified by PCR and cloned in E. coli (Qiagen EZ competent cells). The recombinant E. coli was analysed and confirmed for its expression of phaC1 gene by phase contrast microscopy, Western blot analysis and spectral studies (Fourier-transform infrared spectroscopy). It was further evaluated for its accumulation in different carbon and nitrogen sources. The accumulation of PHA (3.4 g l(-1)) was enhanced in the medium supplemented with glycerol and fish peptone compared to the other carbon and nitrogen sources used in this study. CONCLUSIONS: This study would enable the reduction of cost of PHA production. SIGNIFICANCE AND IMPACT OF THE STUDY: An important part of this study is that E. coli harbouring partial phaC1 gene could accumulate medium chain length PHA significantly. The results demonstrated that the E. coli strain could be a potential candidate for the large-scale production of polymer. The conditions for the higher yield and productivity will be optimized in the next phase using fermentation studies.