Sustainable lactic acid production: Optimization yield from sugarcane and beet molasses through fermentation

• Fermentation Optimization by CCD optimized conditions (40°C, pH 8.0) for 14.2 g/L lactic acid yield at 85 % efficiency. • Molasses Utilization: Sugarcane and beet molasses are economical, sustainable feedstocks. • Strain Efficiency: Kosakonia cowanii (strain 185) achieved 87 % sugar conversion to lactic acid. • Pre-treatment: OPA with calcium carbonate and sodium hydroxide maximized yields. • Industrial Application: Lactic acid supports biodegradable plastics, food, and pharmaceuticals with eco-friendly processes. Lactic acid (LA) is an important organic acid used in various applications and is mainly produced by microbial fermentation. This study improves the production of LA from sugarcane and sugar beet as feedstock. Molasses, a by-product of the sugarcane industry, offers an economical and renewable resource found in fermentable sugars. This study uses a central composite design (CCD) to increase the production of LA by optimizing several fermentation parameters, such as microbial strain, pH, temperature, nutritional supplementation, and fermentation pattern. Calcium carbonate and sodium hydroxide are used to further promote phosphoric acid pretreatment and R 2 (0.99995). The results showed that the production of LA was significantly increased under suitable conditions and predetermined nutritional content. The results showed that the Kosakonia Cowanii variety 185 worked very well. Under optimal conditions (40 °C and pH 8.0), 87 % of the sugar was converted into lactic acid, 87 % of the sugar was turned into LA, and the maximum yield achieved was 14.2 g/L. This means that the strain achieved 85 % efficiency under optimal conditions. This study supports the development of bioeconomic and environmentally acceptable production and improves LA.