Enzymes of Earthworm as Indicators of Pesticide Pollution in Soil

Abstract

The importance of the earthworms in the agricultural practices is well known. The increasing applications of pesticides and chemicals in the agricultural farms have adversely influenced the flora and fauna of the soil. Earthworms which immensely contribute in increasing the quality and fertility of agricultural soil are reported be worst hit organisms under such conditions. Recent reports have indicated growing interests among researchers to explore biochemical and molecular markers as indicators of accumulation of pollutants in the soil in general and pesticides in particular. The varying levels of several biomolecules in different parts of the earthworm have been reported which are indicative of sensitivity of the organisms to different xenobiotics. However, the existing information lacks the literature displaying stock of information regarding the impact of pesticides on the levels of some key enzymes regulating many crucial functions in the earthworm at one place. Keeping in view this issue, it was envisaged to bring out a mini review which illustrates updated information available on the impact of pesticides on the activities of certain key enzymes reported to be responsible for catalysing metabolic pathways concerning the neurotransmission system, energy metabolism, oxidative stress and amino acids metabolism in different body parts of the earthworms, a prospective bioindicators of pesticides contamination in the soil.

Vermicompost Incorporation into Soil Contaminated with Deltamethrin as an Attempt to Reduce the Toxicity Caused by this Pyrethroid: A Structural Study of Soil

“…The no earthworm's growth in the deltamethrin samples suggested that the pyretroid has a toxic effect in their organisms. Rathore and Nollet (2012) and Tiwari et al (2016) asserts for the earthworm's strategy for natural survival: Reducing food intake to avoid the toxins, commonly used in earthworms to avoid poisoning heavy metals and organic chemicals.…”

Effects of contaminated natural soil by Glyphosan SL on biochemical responses of the earthworm Eisenia sp.

“…Since polyunsatured fatty acid peroxides generate MDA, measurement of MDA has been used as an indicator of lipid peroxide (Esterbauer et al, 1991). GPx provides a mechanism for cellular detoxification of peroxides, so this enzymatic reaction plays a crucial role in protecting cell from damage against free radicals, which can be generated by peroxide decomposition (Tiwari et al, 2016). Increased GPx activity in Eisenia sp could be associated with the generation of H 2 O 2 ; a pro-oxidant agent that diffuses easily through the membranes and can react with transition metals, generating the hydroxyl radical (…”

“…In ecotoxicological risks assessment research there is a great interest in the monitoring of terrestrial pollution induced by the widespread use of agrochemicals worldwide, which endangers the ecosystems and the natural resources of the planet (Tiwari et al, 2016). Glyphosate (N-(phosphonomethyl) glycine) is a herbicide widely used for its effectiveness in destroying plants and microorganisms by inhibiting shikimate pathway, and thus it was considered as completely non-toxic to animals and human (Aparicio et al, 2013;Kwiatkowska et al, 2016).…”

“…Molecular mechanisms of protection against ROS include enzymes as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione-S-transferase (GST) and small molecules (that is, reduced glutathione, GSH), which play a crucial role in scavenging ROS generated during aerobic metabolism (Tiwari et al, 2016). GSH plays a key role in the cellular antioxidant defense mechanisms acting directly as oxyradical scavenger and as substrate for GPX and GST (Zhou et al, 2012).…”

“…In addition, biochemical biomarkers can act as early warning signals to prevent environmental damage (Tiwari et al, 2016). Some studies in Eisenia sp have revealed that malathion and chlorpyrifos produce immunotoxicity (Cortesía et al, 2015) and inhibit growth and reproduction (Granadillo and Marcano, 2013).…”