Sustained nutrient delivery system: A new perspective in bioremediation

Crude oil induced pollution on soil environment is an increasing trend due to incessant accidental release of this component into the environment. Bioremediation which is considered the most effective clean-up tool is faced with the challenge of sustained nutrient delivery to enhance and sustain the activities of oleophilic microbes. Slow release fertilizer (SRF) is a purposely designed system that releases nutrients in synchrony with sequential needs of organisms hence they provide optimized nutrient use efficiency. This approach aids in mitigating challenges associated with the conventional fertilizer application such as eutrophication, soil hardening, increased fertilizer loss rate and other environmental devastation. Superabsorbent polymers are hydrophilic gels as they exhibit the ability of swelling and retaining water which supports its use in SRF production. Most SAP used in practice are synthetic and semi-synthetic polymers with high production cost and environmentally unfriendly properties. Natural based polymers such as guar gum, cellulose, chitosan, and starch are abundantly available from plant and other sources but most of these biopolymers have other application which may lead to scarcity for other uses. In most part of the world, enormous quantity of waste is generated which invariably causes pollution. World agro and industrial waste materials with little or no value is therefore recommended to be applied as SAP for SRF formulation. This review therefore provides insight on the potential use of controlled release fertilizer system as a useful tool in ensuring sustained nutrient delivery during bioremediation and also suggest more eco-safe and cost-effective approaches of SRF formulation.