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<p><a href="/public/journals/52/Mr.Singh.jpg" target="_self"><strong><img src="/public/site/images/mmoslemi/Mr._Singh-S_.jpg" alt="" /></strong></a></p><p><strong>Background and Objective:</strong> Sorbitol is a non-toxic and slightly hygroscopic compound with different applications. Zymomonas mobiles produces sorbitol from sucrose or mixtures of glucose and fructose (formation is coupled with the dehydrogenation of glucose to glucono-δ- lactone). Recombinant Zymomonas mobilis may produce sorbitol and gluconic acid from glucose and fructose using different divalent metal ions with reduced the ethanol yield and<br />significantly increased yield of sorbitol. Current study envisaged to alter the media components, physical process parameters and supplementation of amino acids for enhanced sorbitol production.<br /><strong>Material and Methods:</strong> Several process variables were evaluated on sorbitol production including carbon sources (glucose, fructose, maltose, sucrose), carbon concentrations (5, 10, 20 and 25 g l-1), nitrogen sources (peptone, tryptone, yeast extract, beef extract and organic nitrogen mix), temperatures (25, 29, 33, 37, 41°C), pH (6, 6.5, 7 , 7.5 ,8), agitation rate (50, 100, 150, 200 rpm) and amino acids (cysteine, cystine, tryptophan)in batch cultivation of<br />Lactobacillus plantarum NCIM 2912. Shake flask cultivation performed under optimum conditions like temperature 37°C, pH 7.0 and agitation rate of 150 rpm, resulted in enhanced sorbitol production. Comparative study of sorbitol production in solid state fermentation and submerged fermentation was also evaluated.<br /><strong>Results and Conclusion:</strong> Batch cultivation under submerged conditions further performed in 7.5-l lab scale bioreactor (working volume 3.0-l) under optimized conditions resulted in maximum cell biomass of 8.95±0.03 g g-1 and a sorbitol content of 9.78±0.04 g l-1 after 42.0 h of fermentation. Scale up study on bioreactor resulted in maximum sorbitol yield (Yp/x) and productivity of 1.11 g g-1 and 0.50 g l-1 h under submerged fermentation, respectively.<br /><strong>Conflict of interest:</strong> The authors declare no conflict of interest.</p>