Demand for plastics in the world increase drastically in the present context.
Most of the plastics and synthetic polymers are produced from petrochemicals and persistence in the environment creates major management issues. The increased cost of solid waste disposal as well as potential hazards from incineration of wastes such as dioxin emission from PVC makes synthetic plastic waste management a problem (Ojumun et al., 2004).
Packaging industry is growing day by day and in food sector demand for good, safe, eco-friendly packaging material is also increases. Consequently hence, for the past two decades, there have been a growing public and scientific interest in the development and use of biodegradable polymers as an ecologically useful alternative to plastics Polyhydroxyalkanoates (PHA) synthesized by at least 75 different genera of microorganisms is attracted as biodegradable plastics. Hence, in this investigation, attempts were made to isolate PHB accumulating Lactobacillus from diverse sources and to select the efficient strains. The process parameters for maximum PHB production were also optimized. A total of five samples were collected from different sources and isolates were subjected for the detection of PHB accumulation by employing viable colony staining method using Sudan Black B stain. Out of 8 isolates, 5 were found to be PHB good producers. All the 5 PHB positive isolates were subjected to quantitative estimation of PHB.
PHB production, with PHB yields varied from 0.85 to 1.2 gm/lt.
The promising bacterial isolate was selected based on their PHB yield. It was MR-5.The culture parameters were optimized for the selected bacterial isolates, soya extract was found to be the best organic waste source for maximum PHB production 2.80 g/l by all the isolates.Ammonium chloride supplementation at 0.1 percent was found to be optimum and PHB yield 2.95g/ l.
Maintaining the pH of the medium at 6.0 was found optimum with PHB yield 2.3 g/l. Temperature of the growth condition was found optimum at 280C with PHB yield 2.8gm/lt.
Among all tested surfactant Cween80 was found optimum at 280C with PHB yield 2.20 gm/lt. Among all tested trace element ferrous sulphate was found optimum at 280C with PHB yield 1.7gm/lt. Detail morphological and biochemical testing were performed for the possible confirmation of the isolated LB-2 strain; presently the determined characteristics were stated.
Further advanced techniques can apply for confirmation of the isolated strain up to generic and species level.