Improvement in mechanical properties and biocompatibility of biosynthetic bacterial cellulose/lotus root starch composites

• Published in: Chinese journal of polymer science 2017-03, Vol.35 (3), p.354-364
• Main Authors: Yin, Na, Chen, Shi-yan, Cao, Yi-meng, Wang, Hua-ping, Wu, Qing-kai
• Format: Article
• Language: English
• Subjects: Acetobacter xylinum; Bacteria; Biocompatibility; Cellulose; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Industrial Chemistry/Chemical Engineering; Low concentrations; Mechanical properties; Media; Morphology; Polymer Sciences; Roots; Starches; Tensile tests; X-ray diffraction
• ISSN: 0256-7679; 1439-6203
• DOI: 10.1007/s10118-017-1903-z

Bacterial cellulose/lotus root starch (BC/LRS) composites were prepared by cultivating Acetobacter xylinum in nutrient media containing gelatinized lotus root starch. Low concentrations of gelatinized LRS had increased BC production with the maximum value at 6.67 g/L when 5 g/L of LRS was added in the culture media and the composites had thicker and denser fibrils compared with those of BC with low concentrations of LRS (2.5 and 5 g/L). When the concentration of LRS was increased above 7.5 g/L, the morphology of the BC/LRS composites contained more fibril layers that were linked with LRS. The results from X-ray diffraction (XRD) demonstrated that there was no significant difference in structure between BC and BC/LRS composites except a slight increase in crystallinity for BC/LRS composites as the concentration of LRS was lifted up. The tensile tests were performed to display BC/LRS composites prepared with LRS concentration at 2.5 and 5 g/L in media had the tensile strength of 54 and 60 MPa, respectively, which indicated an improvement in mechanical property compared to the unmodified BC (45 MPa). Live/dead assay with chondrocytes seeded on BC/LRS composite revealed higher cell viability ranging from 85% to 90% than BC. Furthermore, cell morphology with typical spindle shape was observed on the surfaces of BC/LRS composite by confocal microscope. Through the overall results, it shows that this study has provided a guidance to prepare BC/LRS composites with better cell biocompatibility and higher mechanical strength than those of BC for the potential use in cartilage tissue engineering.