APPLICATION OF CORN STEEP LIQUOR AS FACTORY OVERPLUS PRODUCTS AND NITROGEN SOURCE FOR OPTIMIZATION PROCESS OF BACTERIAL CELLULOSE PRODUCTION USING RESPONSE SURFACE METHODOLOGY

Background and Aim:Bacterial cellulose (BC) that is produced by various species of bacteria especially genus Gluconobacter have certain properties and different applications. High purity, appropriate tensile strength, water absorbance and maintenance also biocompatibility and biodegradability are some of BC unique characteristics. Examples of BC applications include substrate for preparation of bioscafolds and targeted drug delivery. Therefore, increasing BC production efficiency is highly demanded. In this research, a cheap and overplus factory products (corn steep liquor or CSL) have been used as nitrogen source for BC production. BC production was then optimized along with other factors using response surface methodology (RSM).Methods:In this study, optimization process was performed in 3 levels using Acetobacter xylinum BPR2001. Five detrimental factors including pH (5, 6, 7), 20 g/L fructose-glucose ratios (1:1, 1:3 and 3:1), bacterial inoculation quantities (5%, 10%, 15%), ethanol (0%, 1% and 2%) and finally inexpensive extra factory products CSL (40, 80 and 120 ml/L) were considered in 46 designed experiments which all incubated at 28oC for 7 days in static culturesResults:RSM analysis showed that pH 5, fructose-glucose 1:3 ratio, 2% ethanol; bacterial inoculation quantity 15% and 120 ml/L CSL increased BC production efficiency from its basic level in standard culture (Hestrin- shrime) which was 8 g/L to 11.55 g/L.Conclusion:Overplus factory CSL in comparison to commercial CSL (Sigma-Aldrich) not only is more affordable but also can increase BC production efficiency up to 40%. Therefore it is suggested for BC mass production.

کلیدواژه ها:

Bacterial cellulose ، Overplus factory products ، Corn steep liquor ، Response surface methodology