Biotechnology Application in Starch/Natural Rubber Polymer Degradation: Panacea for Rubber Waste Disposal and Utilization

Reckless burning of expired automobile tyres and used rubber products and their disposal at refuse dumps pose serious waste disposal and pollution problems.Incorporation of starch bio-filler into natural rubber, NR opens up better structural surface in rubber that provides microorganisms a platform to act or feed on rubber molecule, cis-1,4 polyisoprene and subsequent breakdown into smaller low molecular weight components.Starch was extracted from Polynesian arrow root crop(amora), Tacaleonto petaloid.powdered, gelatinized and converted into starch/natural rubber blend by direct mixing and co-coagulation.It was thereafter compounded in a two-roll mill according to American Society of Testing and Materials (ASTM), D3184-80 and cured using sulphur and accelerators method of curing.The starch/ NR composite samples were subjected to the activities of isolated Pseudomonas aeruginosa, Bacillus sp, and Bacillus megaterium carried out under a closed system using mineral salt medium (MSM)procedure.Biodegradation activity was found to be at maximum in sample F0(cured rubber without starch filler).It was discovered that bacteria samples isolated from a botanical garden in North-east Nigeria could not act on the rubber samples under study while the bacteria isolated from the Rubber plantation at Rubber Research Institute, (RRIN) Iyanomo, Edo State acted on the starch/ rubber samples with positive breakdown products.These bacteria isolated from RRIN has exhibited selective adaptation in their ability to degrade rubber samples under study.Probably some bacterial enzymes were involved in this activity which are yet to be investigated and is open for further investigation.In this regard, biotechnology application is a potential panacea for rubber waste disposal and utilization.