Molybdenum disulfide-enhanced bacterial cellulose through static fermentation: Optimisation and structure–property relationships

Abstract

Bacterial cellulose (BC) is a high purity nanofibrillar biopolymer with promising applications in textiles, packaging, and biomedicine. Here we report a fermentation-integrated strategy to modulate BC production and structure by introducing molybdenum disulfide (MoS2) nanosheets during SCOBY (symbiotic culture of bacteria and yeast) cultivation. MoS2 was added at concentrations of 0.2–0.6% (w/v) and compared against an untreated control under static conditions (30°C, pH 5.0, 14 days). Production metrics, FTIR spectroscopy, and X-ray diffraction (XRD) were employed for characterisation. At 0.3% MoS2, volumetric productivity increased from 4.2 to 11.3 g·L-1·day-1 (≈169% increase, p < 0.05). FTIR analysis revealed a band at 1033 cm-1, indicating partial MoS2 oxidation (S=O/Mo–O vibrations) and interfacial bonding with cellulose. At concentrations ≥0.4%, nanoparticle aggregation reduced productivity and crystallinity. This work demonstrates a bio-fabrication route to tune BC structure-property profiles via inorganic nanosheets and elucidates dose-dependent mechanisms balancing microbial activity with filler dispersion.