Modares Journal of Biotechnology

Abstract Aims: Recently, polymer-based nanofibrous scaffolds have attracted great attention due to their significant antibacterial properties in the field of dermatological applications. In this study, a polycaprolactone-based nanofibrous scaffold has been fabricated using the electrospinning method. The aim of this study was to evaluate the antibacterial effect of electrospun nanofibrous structures. Materials and Methods: In this experimental study, the structure and bacterial attachment on polymeric nanofibrous scaffolds were studied by Scanning Electron Microscopy (SEM). In addition, antibacterial properties of nanofibrous scaffolds were studied on two gram-negative bacteria of Escherichia coli and Pseudomonas aeruginosa and two gram-positive bacteria of Staphylococcus aureus and Streptococcus mutans, using microdilution method and biofilm assay. Moreover, MTT assay was performed on HeLa and human fibrosarcoma cell line (HT1080) cancerous cell lines to evaluate the cell viability.
Findings: The results of this study showed that nanofibrous scaffold revealed a significant antimicrobial and anti-biofilm formation effect on all of the studied bacterial strains, but in microscopic observations and microdilution assay was observed on Pseudomonas aeruginosa in 1mg/ml of nanofibrous scaffold extract concentration, while the major effect in biofilm assay was observed in 8µg/ml of extract concentration. Moreover, the cell viability studies showed that the most significant effect was shown on HT1080 cell line which has drastically decreased by 40% after 48 hours in comparison with the control.
Conclusion: These results show that electrospun nanofibrous PCL-based scaffolds are potentially promising for dermal tissue engineering applications, due to anti-biofilm effects and capability of reducing the number of cancerous cells in the wound site.

Abstract Aims: Considering the importance of health and some disadvantages of the existing synthetic compounds, the present research aimed at evaluating the antibacterial and antioxidant potential of Haliclona caerulea extracts.
Materials and Methods: In the present experimental study, organic extracts of n-hexane, diethyl ether, and methanol were prepared by the Bligh and Dyer method from the marine sponge; then, antibacterial activity was measured by disc diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC), and antioxidant activity was measured by evaluating the regenerative power and determining the total antioxidant capacity of the extracts. The data were analyzed by Duncan's new multiple range test (MRT) one-way ANOVA test. SPSS 19 and Excel 2013 software were used.
Findings: Methanol extract had the most antibacterial effect, especially against Gram positive bacterial of Bacillus subtilis with a concentration of 2.5mg/ml and Staphylococcus aureus with a concentration of 5mg/ml. Diethyl ether extracts showed the highest antioxidant activity at concentration of 5mg/ml.
Conclusion: The methanol extract of Haliclona caerulea exhibits more antibacterial properties, and the diethyl ether extract of this sponge have a higher antioxidant effect.