Exploring the role of hydroxyapatite on production of bacterial cellulose and its physiochemical properties

Bacterial cellulose (BC) is the purest form of cellulose. BC is highly biodegradable and biocompatible in naturewhich stands it as a suitable alternative for petroleum-based plastics. In this study, the surface of linen fabric (LiF) was modified by depositing BC over it by in-situ cultivation method. The fermentation process was carried by using Gluconacetobacter liquefaciens (MTCC 3135) as BC producer. To increase the productivity of BC, hydroxyapatite (HA) was used as a suitable supplement in the HS medium. For this varying concentration of HA ranging from 0.25 to 4.5% (w/w) of HS medium was added in the culture medium. Maximum BC production of 8.48% was obtained by supplementing the culture medium with 4.5% HA (%w/w). The least BC production of 1.57% was observed at 1.5% HA. In addition, composites of BC deposited LiF were prepared by using HA as reinforcing agent. For this, varying concentration of HA i.e., ranging from 1 to 5 (%w/w) were incorporated in BC deposited LiF through solution casting method. The resulting BC deposited LiF and its derived composites were characterized in terms of their various physicochemical and structural parameters. Microscopic study confirms the deposition and random distribution of BC and HA for later over the surface of LiF respectively. FTIR analysis confirmed the deposition of BC and HA over the surface of LiF and all samples exhibited similar absorption peaks for BC deposited LiF and HA based composites respectively. XRD profile showed varying crystallinity index (CI), highest in the composite prepared by incorporating 1% HA i.e. CI value of 77.56. The water-holding capacity of composites was found to be lower than that of the alkali-treated LiF. Mechanical properties exhibited an increasing trend in tensile stress by an increase in HA concentration. Among BC deposited LiF, with 4.5% HA had the highest tensile stress of 45.73 MPa while among composites LiF with 5% HA had the highest tensile strength of 45.89 MPa. No zone of inhibition was formed in response to E. coli, P. aeruginosa and S. aureus confirming no antibacterial activity of the composites. Based on the tailored mechanical property and moisture retention, this composite emerged as a suitable candidate which can be further explored for its potent application in bone tissue engineering.