ORIGINAL PAPER Utilizing of Sugar Refinery Waste (Cane Molasses) for Production of Bio-Plastic Under Submerged Fermentation Process Abhishek Dutt Tripathi • Ajay Yadav • Alok Jha • S. K. Srivastava Published online: 24 November 2011 Ó Springer Science+Business Media, LLC 2011 Abstract In the present study, depending upon the availability and cheaper cost, different carbon source were tested for the production of PHAs (Polyhydroxyalkonoates) by soil bacterium Pseudomonas aeruginosa and it was found that sugar refinery waste (cane molasses) produced the maximum PHA (biodegradable polymer) which is precursor for bio-plastic development. Urea served as potent nitrogen source over other inorganic nitrogen sour- ces in bio-plastic synthesis. Effect of different physical parameters viz; pH, temperature and agitation speed were also studied on PHA production. Batch cultivation kinetics under optimized cultural and physical condition showed maximum cell mass and PHA concentration of 7.32 ± 0.2 and 5.60 ± 0.3 g/L, respectively after 54.0 h of cultiva- tion. Sugar refinery waste (Total sugar 4%) and urea (0.8%) improved the economics of the process which exhibited a yield (Y P/X ) of 0.70 with productivity of 0.11 g/L/h. PHA was further characterized as PHB by using Fourier Trans- form Infra-red Spectroscopy (FT-IR). Keywords PHAs (Polyhydroxyalkanoates) Á Pseudomonas aeruginosa Á Bio-plastic Á Physical variables Á Fourier transform infra–red spectroscopy (FT-IR) Introduction Today, polymers have become a necessary part of con- temporary life pertaining to their durability and resistance to degradation. Worldwide production of petroleum based synthetic polymer was approximately 270.0 million tons in 2007 [1] and these synthetic polymers are found to be recalcitrant to microbial degradation [2]. Problems related to solid waste management of non-biodegradable (petro- chemical derived) plastics poses a serious threat to global environment. Therefore, current concerns about the envi- ronmental fate of polymeric materials have created much interest in the development of biodegradable plastic (bio- plastic) that still retain the desired physical and chemical properties of conventional synthetic plastics. Bio-plastic are developed from renewable agricultural or biomass feedstock which mimicked the properties of conventional plastics production and are degradable through microbial processes upon disposal [3]. Typically, the biopolymers can be made from different bacterial genera including Azetobacter, Bacillus, Alcaligens, Pseudomonas, Rhizo- bium and Rhodosprillum which produces PHAs (Polyhy- droxyalkanoates). PHAs, are polyesters synthesized intracellularly and stored as a carbon and energy storage material by numerous bacterial species under starved growth conditions which provide a degradable alternative to petrochemical plastics [4, 5]. Poly-3-hydroxybutyrate (PHB) is a well characterized PHA produced under phos- phate limiting condition and posses physical properties similar to various thermoplastics and elastomeric com- pounds (from polypropylene to synthetic rubber) and are completely biodegradable and biocompatible under aerobic and anaerobic environment [6–8]. However, PHB finds limited applications due to its high production cost, low thermal stability and excessive brittleness upon storage. A. D. Tripathi (&) Á A. Yadav Á A. Jha Centre of Food Science and Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India e-mail: abhi_itbhu80@rediffmail.com S. K. Srivastava School of Biochemical Engineering, Institute of Technology, Banaras Hindu University, Varanasi 221005, India 123 J Polym Environ (2012) 20:446–453 DOI 10.1007/s10924-011-0394-1