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Background: : The world’s annual utilization of plastic materials is growing day by day and simultaneously solid waste management is becoming one of the major environmental concerns throughout the world. Current approach for their usage and disposal is not sustainable because of the durability of the polymers involved. Methods: : Partially digested products of these plastics in the form of micro-plastics are accumulating as debris in landfills and in natural habitats because of their remaining in the environment for millions of years. Easy availability, low cost and ubiquitous applications make the plastics most attractive polymer whose proper disposal through specific technology seems the only alternate and that may lessen down the pollution over the next decades. Results: : Recycling as a waste management strategy provides opportunities to reduce the use of petrochemical resources and improving environmental conditions. Reuse of bulky plastic wastes in concrete and Wood Plastic Composites (WPC) seems a smart approach for solving the problem of disposal. The development of new construction materials using recycled plastics is important to both the construction and the plastic recycling industries. Conclusion:: This review article presents the details of recycling of waste management, their probable application for concrete and WPC production, types of recycled plastics, role of microbes and microbial enzymes for recycling of plastics and emphasis on use of biodegradable plastics to make the environment green.

Bioplastics, synthesized by several microbes, accumulates inside cells under stress conditions as a storage material. Several microbial enzymes play a crucial role in their degradation. This research was carried to test the biodegradability of poly-β-hydroxybutyrate (PHB) utilizing PHB depolymerase, produced by bacteria isolated from sewage waste soil samples. Potent PHB degrader was screened based on the highest zone of hydrolysis followed by PHB depolymerase activity. Soil burial method was employed to check their degradation ability at different incubation periods of 15, 30, and 45 days at 37±2°C, pH 7.0 at 60% moisture with 1% microbial inoculum of Aeromonas caviae Kuk1-(34) (MN414252). Without optimized conditions, 85.76% of the total weight of the PHB film was degraded after 45 days. This degradation was confirmed with Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscope (SEM) analysis. The presence of bacterial colonies on the surface of the degraded film, along with crest, holes, surface erosion, and roughness, were visible. Media optimization was carried out in statistical mode using Plackett Burman (PB) and Central Composite Design (CCD) of Response Surface Methodology (RSM) by considering ten different factors. Analysis of Variance (ANOVA), Pareto chart, response surface plots, and F-value of 3.82 implies that the above statistical model was significant. The best production of PHB depolymerase enzyme (14.98 U/mL) was observed when strain Kuk1-(34) was grown in a media containing 0.1% PHB, K2HPO4 (1.6 gm/L) at 27 ℃ for seven days. Exploiting these statistically optimized conditions, the culture was found to be a suitable candidate for the management of solid waste, where 94.4% of the total weight of the PHB film was degraded after 45 days of incubation.