Contaminated Soil Phytoremediation byCyperus LaxusLam. Cytochrome P450 Erod-Activity Induced by Hydrocarbonsin Roots

Abstract

Laboratory and greenhouse experiments with Cyperus laxus Lam were conducted to determine the rate and extent of phytoremediation and the effect of hydrocarbons on the cytochrome P450 EROD (7-ethoxyresorufin-O-deethylase) enzymatic activity in roots. Plants were cultivated on hydrocarbon-contaminated soil (HCS) and spiked perlite. Phytoremediation was evaluated using 6.5 kg HCS (173 +/- 15 mg total petroleum hydrocarbons [TPH] g(-1) of dry soil) pots at different moisture contents; the average removal rate was 3.46-0.25 mg TPH g(-1) dry soil month(-1) and 48% was removed when moisture was kept at 60%. The aromatic hydrocarbon fraction was the mostly removed, 60%; aliphatic, 51%; and polar 24% after 24-month experiments. In unplanted pots, TPH concentration did not exhibit significant differences with respect to the initial concentration. We confirmed that the presence of hydrocarbons induced ERODactivity up to 6.5-fold. Moreover, short-term experiments (up to 13 d) with spiked perlite demonstrated that two EROD activities in roots contributed to the total detected; 60% was found in the cytosolic and 40% in the microsomal fraction. To our knowledge, this is the first work that tries to build links between the hydrocarbon-inducible character of ERODactivity in roots and the phytoremediation ability of C. laxus in highly contaminated soils.

Axonopus compressus (Sw.) P. Beauv. A native grass species for phytoremediation of hydrocarbon‐contaminated soil in Assam, India

“…The slower and reduced degradation of TPH in uncontaminated soil can be attributed to its lack of plants. Lopez‐Martinez et al 25 also found significant reduction of TPH by Cyperus laxus Lam. over 24 months when plants were cultivated on hydrocarbon‐contaminated soil and spiked perlite.…”

Enzymatic defense of Cyperus brevifolius in hydrocarbons stress environment and changes in soil properties

“…It has been suggested that root exudates which control the quality and quantity of microbial population in soil also alter plant metabolism during crude oil associated stress condition thereby promoting the degradation of hydrocarbons/oil in vegetated treatments 6 . Several studies have showed significant changes in TOG profiles in oil polluted soils after treatment by herbs/ grasses [22][23][24] . Nevertheless, reduction in TOG levels (17.36%) in the present study was found comparatively less as against the previous works which can be because of the time duration of the experiment (60 days), besides the high concentration levels of crude oil of the experimental soil.…”

Phytoabsorption of heavy metals from leachates using the species Cyperus laxus y Chrysopogon zizanioides

“…Its common name is "Pelo de Chino", but in some states of the country like Veracruz, it is known as "Zacate Chontul" (López, 2013). It taxonomically belongs to the Tracheophytes division of the class Angiospermae and sub-classes Monocotyledonous, it is in the Family Cyperaceae, and belongs to the genus: Cyperus, species: Cyperus laxus lamouroux (López et al, 2008).…”

“…To date, studies and assessments related to C. laxus remain scarce, but there are other successful cases in which the Cyperus genus has been used (Escalante et al, 2005;López et al, 2008).…”