Shrimp-waste based dispersant as oil spill treating agent: Biodegradation of dispersant and dispersed oil

Abstract

The emerging demand for the enhancement of biodegradation of persistent organic pollutants from marine oil spills using oil-treating agents to minimize the environmental impacts promotes the development of green dispersants. Shrimp waste is a potential raw material to generate green dispersants. The biodegradability of dispersed oil and dispersants themselves are key factors for the national consideration of the approval, stockpile, and usage of dispersants. However, it is unknown whether shrimp-waste-based dispersant (SWD) has high bioavailability or facilitates the biodegradation of dispersed oil. In this study, we tackled the biodegradation of oil dispersed by a purified SWD. Furthermore, the SWD biodegradability was evaluated by exploring the degradation genes via metagenomic sequencing, analyzing the enzymatic activities for dispersant biodegradation by molecular docking, and discussing the SWD toxicity. We discovered that the SWD facilitated the biodegradation of two crude oils (Alaska North Slope and Marine Fuel-No.6). The metagenomic analysis with molecular docking showed that fresh seawater had feasible enzymes to degrade the SWD to safety components. Additionally, the SWD was low toxic and high bioactive. The findings helped confirm that the purified SWD is an effective and eco-sustainable marine oil spill treating agent and tracked the biodegradation of dispersed oil and the SWD.

Keywords: Biodegradation; Dispersed oil; Green dispersant; Metagenomics; Oil spill.