Evaluation of Different Biomolecules in Two Epigeic Earthworms Cultured in Microplastic-Treated Foods

Plastic use has increased significantly in terrestrial habitats, mainly microplastics (MPs) like Polyvinyl Chloride (PVC), in agricultural ecosystems for various purposes. Microplastics are known to adversely affect earthworms in soil ecosystems, including growth and reproduction. Here, we used the No Observed Effect Concentration (NOEC) (4 g/100 g of CM) to assess the influence of microplastics (MPs) on the composition of dif erent biomolecules in two epigeic earthworms, Eisenia fetida (EF) and Eudrilus eugeniae (EE). We analysed major biomolecules, including proteins, Carbohydrates (Glucose), and Lipids, in earthworm biomass using standard methods. The results showed that MP treatment increased protein content in earthworm EF (806.18 mug/ml) and decreased it in EE (688.55 mug/ml). In contrast, MP treatment decreased glucose content in both earthworm species (EF-470.01 and EE-515.82 mug/ml) compared with Control-CM (EF-578.50 and EE-540.83 mug/ml), respectively. Total lipid content was higher in EF-MPT (0.2008 g) than in Control-CM (0.1594 g), but lower in EE-MPT (0.1336 g) than in Control-CM (0.1784 g). Saturated lipids were higher in EF-MPT (0.0842 g) and lowerin Control-CM (0.065 g), whereasin EE, they were higherin Control-CM (0.0744 g) than in MPT (0.028 g). For unsaturated lipids, EE-MPT showed the maximum (0.1056 g) and Control-CM the minimum (0.104 g), whereas Control-CM showed less (0.0944 g) and MPT more (0.1166 g) in the case of EF. Hence, based on these results, both epigeic earthworm species contain all major biomolecules in various forms. Still, microplastic exposure can positively or negatively influence the composition and percentage of these biomolecules in different earthworm species.