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Bacterial cellulose (BC) is a very fascinating microbial biopolymer which is mainly produced by Gluconacetobacter xylinum. Optimization of BC production by G. xylinum was performed based on scale-down studies in miniature-bioreactor and response surface methodology in which the optimum pH value (6.5) and shaking rate (50 rpm) were obtained. The static culture condition for BC production has newly been defined. Nanostructure of BC includes nanofibers up to (60 nm) and nanoporosity up to (265 nm) was observed by scanning electron microscopy. By Fourier transform infrared spectroscopy study, the most expected BC interaction is nucleophilic interaction. MTT assay showed high biocompatibility. Appropriate mechanical strength (0.37 MPa) and Young's modulus (3.36 MPa) evinced BC scaffold utilization for skin tissue. The results indicate that BC sheets can be utilized in biomedical application and nanotechnology approaches.

Gonadotropin-releasing hormone (GnRH) analogs (e.g., triptorelin) are developed to treat hormonedependent reproductive cancers. However, these analogs lack any signi cant direct antitumor activity to make them suitable for hormone-refractory reproductive cancers. In this study, we modi ed GnRH peptide and triptorelin to improve their stability, pharmacokinetic properties, and potency and subsequently broaden their clinical applications in cancer. We investigated biological properties of lipid-modi ed GnRH analogs, with/without D-amino acid substitution at position 6 to yield GnRH-and triptorelin-based derivatives, respectively, in prostate and ovarian cancer cells. We showed that the improved stability due to lipid-modi cation and D-amino acid substitution played a pivotal role in enhancing GnRH receptormediated direct antiproliferative activity (up to 4.5-fold higher than triptorelin) and gonadotropin-releasing potency. Furthermore, sex steroids played signi cant but contrasting roles in regulating the direct antiproliferative activity of the lipopeptides in cancer cells. The superior activity of these GnRH analogs over triptorelin renders promises for developing new GnRH receptor ligands to treat hormone-dependent and -refractory cancers, as well as emerging new targeting moieties for the delivery of anticancer agents in GnRH receptor-overexpressing cancers.

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