Scalable production of hyaluronic acid from Bacillus paralicheniformis PV154040.1 under optimized conditions: a GRAS-based bioprocess for biomedical and cosmetic applications.

This study establishes a scalable, GRAS-compliant bioprocess for hyaluronic acid (HA) production using Bacillus paralicheniformis PV154040.1, a novel strain isolated from local garden soil and identified via ribotyping. Through the systematic optimization of submerged fermentation conditions, M4 medium (5% glucose, 5% lactose, 1.5% tryptone, and 0.5% yeast extract) was identified as the most productive formulation. The optimal culture parameters were determined to be pH 6.5, a 72-hour incubation at 37 °C, and a 1.0 ml inoculum volume. A key finding was the significant enhancement in HA recovery using a cetyltrimethylammonium bromide (CTAB)-ethanol extraction method, which yielded 374.21 µg/ml, doubling the yield obtained with conventional ethanol precipitation (188.33 µg/ml; *p* ≤ 0.05). The identity of the biopolymer as HA was confirmed by Ultraviolet-Visible (UV/Vis) spectrophotometry, which showed characteristic absorbance, and FTIR analysis, which revealed functional peaks corresponding to glycosidic linkages (834.92 cm⁻¹), proteoglycan sugar rings (998.92 cm⁻¹), amide II (1617.66 cm⁻¹), and hydroxyl groups (3257.69 cm⁻¹). This work presents the first report of HA production by B. paralicheniformis, introducing a safe, efficient, and sustainable microbial platform as a promising potential alternative to traditional animal-derived or pathogenic sources for biomedical and cosmetic applications.