Abstract
Polyvinyl alcohol (PVA) degrading bacterial strains were isolated from various environmental sites rich in plastic wastes by using the enrichment culture technique. Among the various isolated strains, the selected potent PVA degrading bacterial strains were tentatively characterized as Bacillus and Pseudomonas sp. The time course of the PVA degradation potential of the characterized strains in growth media containing PVA as a major carbon source was evaluated using the spectropho-tometric assay method. This was done by determining the residual PVA remaining in the culture media, increase in cell growth and change in pH of the media over a period of twenty days. The ultimate biodegradation (mineralization) of PVA to its mineral constituents CO2 and H2O was determined by the CO2 evolution test. The strain characterized as Bacillus sp. showed 65% of PVA degradation as determined by spectrophotometric assay and 45.4% of mineralization of PVA over a period of 20 days. The strain characterized as Pseudomonas sp. showed 42% of PVA degradation as determined by spectrophoto-metric assay and 28.9% of mineralization of PVA over a period of 20 days. Key words: Polyvinyl alcohol (PVA) degrading bacteria, isolation, ultimate biodegradation, mineralization.
Highlights
Use of biodegradable, or single use disposable items as a replacement of inert synthetic plastics is gaining wide scale recognition due to its potential in overcoming, or at least reducing issues associated with the management of the post consumption status of synthetic plastics waste
From enrichment cultures incorporated with Polyvinyl alcohol (PVA) and incubated for two weeks at 30°C, 30 morphologically different bacterial isolates were obtained on the nutrient agar
The present study describes enrichment, isolation and characterization of microbial strains degrading PVA
Summary
Single use disposable items as a replacement of inert synthetic plastics is gaining wide scale recognition due to its potential in overcoming, or at least reducing issues associated with the management of the post consumption status of synthetic plastics waste. PVA is a vinyl polymer where the main chain is joined by only one carboncarbon linkage (-CH2-CHOH-)n. This linkage is the same as those of typical plastics, such as polyethylene, polypropylene and polystyrene. Biodegradability of this material is mainly due to the presence of the hydroxyl group, which leads to its water solubility and susceptibility to oxidation (Kawai, 1995). Due to these properties, biodegradable plastic based on PVA gains popularity among biodegradable plastics, and is widely used in packaging and agricultural mulch film (Bastioli et al, 1993). Four major segments of PVA consumption include wrap sizing, paper coating, adhesives, films and biodegradable PVA items for example mulching films, laundry bags, etc. (Chiellini et al.,1999)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
