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PubMed2006

[Establishment of method for cytochrome P450 of earthworms (Eisenia fetida) as a biomarker].

Earthworm (Eisenia fetida) was chosen as test soil fauna to establish the method for determination of cytochrome P450 content. By means of thoroughly washing with salt solution, changing centrifugal acceleration and dissolving microsomal membranes of earthworms with sodium cholate, the determination of cytochrome P450 was performed. Base on the method, dynamic relationships of dose-response for cytochrome P450 contents in earthworm and phenanthrene concentrations were conducted by contact filter paper and soil contaminated with phenanthrene. Results indicate that cytochrome P450 are covered up by interferential material in earthworm, which makes the classic peak lag and appear at 455 - 457nm in the CO difference spectrum with a spectrophotometer. Through increasing centrifugal acceleration and adding reagent of solubilization, the interference is removed mostly and the classic peak of P450 returns to appear at 450nm +/- 1nm. The exposure tests of phenanthrene with contact filter paper (10(-6), 10(-5), 10(-4), 10(-3) and 10(-2) mg x mL(-1)) and soil (1, 2, 4 and 8 mg x kg(-1)) reveal that the dose-response relationships exist between the pollutant and cytochrome P450. Soil tests of different exposure durations (1, 3, 7, 14 and 28d) show the effects of different phenanthrene concentration on earthworm cytochrome P450 contents are to activate (7d) and to inhibit (14d and 28d), and the content of P450 is 0.99 - 1.41 and 0.77 - 0.88 (p < 0.05) times of control respectively. From this study, cytochrome P450 content of earthworm has the merit of simpleness, speediness and economy for determination, and it could be used as a sensitive biomarker for monitoring the exposure of sublethal pollution in terrestrial ecosystem.

Animals↗

PubMed1996

[Chemical composition of earthworm (Eisenia fetida and Lumbricus rubellus) silages].

Earthworms (Eisenia fetida and Lumbricus rubellus) were ensiled with ground sorghum and molasses in the following proportions: 1) 60% earthworms, 40% sorghum; 2) 60% earthworms, 40% sorghum, adjusting pH to 4.0 with HCl; 3) 60% earthworms, 20% sorghum, 20% molasses; 4) 60% earthworms, 20% sorghum, 20% molasses, adjusting pH to 4.0 with HCl. These mixtures were allowed to ferment for 15 days at 18 degrees C. pH, proximate chemical analyses, digestible protein, true protein, ammonia nitrogen, acetic, propionic and butyric acid, lactic acid and gross energy were analyzed in the ensiled mixtures. Data were analyzed by ANOVA and orthogonal contrasts. No differences (P > 0.0001) were found in the percentage of moisture, ether extract, crude fiber and crude protein (52.22, 2.96, 1.15, 22.00, 51.76, 3.48, 1.28, 20.17; 53.89, 3.23, 0.95, 20.63; 54.87, 2.99, 1.03, 21.14, for treatments 1, 2, 3 and 4, respectively). Neither there was any difference (P > 0.0001) for true protein and gross energy (7.57, 4.37; 6.92, 4.41; 5.45, 4.37; 6.38, 4.30, for treatments 1, 2, 3 and 4, respectively). Ash content (P < 0.0001) and nitrogen free extract (p < 0.02) were different between treatments with sorghum and treatments with sorghum and molasses (3.80, 70.09; 3.60, 71.47; 6.08, 69.11; 6.63, 68.21, for treatments 1, 2, 3 and 4, respectively). Digestible protein was also different (P < 0.01) for treatment 1 (96.78) than 2 (94.34). pH values were lower (P < 0.03) for treatment 2 (3.80) and 4 (3.76), where HCl was added than for 1 (4.06) and 3 (4.16). Ammonia nitrogen values were very low for all treatments. Lactic:acetic acid ratio was large for all treatments (7.55, 14.83, 8.30, 7.63 for treatments 1, 2, 3 and 4, respectively). It is concluded that it is possible to preserve the earthworms E. fetida and L. rubellus by ensiling, adding a source of carbohydrates, such as sorghum or molasses. Not being necessary the addition of acids to have an adequate fermentation.

Animals↗

PubMed1998

Interactions between the nematode parasite of pigs, Ascaris suum, and the earthworm Aporrectodea longa.

Pig faeces in which Ascaris suum eggs had been embryonating for 57 days were placed in buckets of soil containing either 30 or no earth-worms (Aporrectodea longa). When present, earthworms consumed the faeces and transported the eggs down into the soil, without inflicting any visible damage on the eggs. In later experiments 10 earthworms from the above experiment were fed to each of ten pigs, and another 40 earthworms were dissected. None of the 10 pigs became infected with A. suum through consumption of earthworms, and none of the dissected earthworms were found to contain A. suum larvae. This experiment indicates that A. longa did not act as a paratenic host for A. suum but shows that earthworms are very efficient in transporting A. suum eggs from faeces deposited on the soil surface into the soil.

Animals↗

PubMed1999

Stable isotopic studies of earthworm feeding ecology in tropical ecosystems of Puerto Rico.

Feeding strategies of earthworms and their influence on soil processes are often inferred from morphological, behavioral and physiological traits. We used (13)C and (15)N natural abundance in earthworms, soils and plants to explore patterns of resource utilization by different species of earthworms in three tropical ecosystems in Puerto Rico. In a high altitude dwarf forest, native earthworms Trigaster longissimus and Estherella sp. showed less (15)N enrichment ((15)N = 3-6 per thousand) than exotic Pontoscolex corethrurus ((15)N =7-9 per thousand) indicating different food sources or stronger isotopic discrimination by the latter. Conversely, in a lower altitude tabonuco forest, Estherella sp. and P. corethrurus overlapped completely in (15)N enrichment ((15)N = 6-9 per thousand), suggesting the potential for interspecific competition for N resources. A tabonuco forest converted to pasture contained only P. corethrurus which were less enriched in (15)N than those in the forest sites, but more highly enriched in (13)C suggesting assimilation of C from the predominant C(4) grass. These results support the utility of stable isotopes to delineate resource partitioning and potential competitive interactions among earthworm species. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗

PubMed1995

Earthworm and food interactions on bioaccumulation and disappearance in soil of polycyclic aromatic hydrocarbons: studies on phenanthrene and fluoranthene.

The present study describes some novel phenomena with regard to the environmental fate of polycyclic aromatic hydrocarbons (PAHs) in the terrestrial soil environment. Laboratory experiments were conducted on: (1) the influence of earthworms on the disappearance rate of PAHs in soil, and (2) the bioaccumulation of these compounds in the earthworm body. It is demonstrated that the disappearance of phenanthrene and fluoranthene in soil is accelerated by the presence of the earthworm Lumbricus rubellus. Possible explanations and practical implications of this effect are discussed. In the bioaccumulation part of the study it is demonstrated that earthworms may take up and accumulate fluoranthene and, to a lesser extent, also phenanthrene in their body tissues. Bioaccumulation was found to be reduced by changes in bioavailability associated with aging of the PAH-amended soil. Finally, it was observed that earthworms indicate a strongly enhanced bioaccumulation of PAHs under conditions of food limitation.

Analysis of Variance↗

PubMed1988

Isolation and initial characterization of myelin-like membrane fractions from the nerve cord of earthworms (Lumbricus terrestris L).

We report here the isolation of fractions enriched in components of the myelin-like membranes surrounding the giant axons of the earthworm. Lumbricus terrestris L. The composition and purity of the fractions have been assessed using SDS-protein electrophoresis, Western immunoblots, and electron microscopy. Preliminary enzyme assays indicated that the mitochondrial marker, succinate dehydrogenase, has a similar specific activity distribution in earthworm nerve cord and in mouse liver sedimentation velocity fractions, however, the distribution of the total units of activity among the fractions seems to indicate the existence of smaller mitochondria in earthworm nerve cord compared with mouse liver mitochondria. In earthworm nerve cord fractions, Na+/K+ ATPase and Ca2+/Mg2+ ATPase were found to be enriched exclusively in the fraction containing large plasma and myelin-like membranes, while in the mouse liver fractions, the total units of these two enzymes were found to be distributed broadly among fractions. 5'-Nucleotidase activity in the earthworm nerve cord seemed to be restricted to the microsomal fractions (endomembrane network), with a very low activity associated with the large plasma and myelin-like membrane fraction. We have established the presence of keratins or prekeratins in the myelin-like membranes, probably in the form of tonofilaments. However, we could not show that the desmosome-like structures, characteristic of these membranes, are composed of those proteins described for vertebrate epithelial desmosomes.

Animals↗

PubMed1988

Uptake and accumulation of pentachlorophenol and sodium pentachlorophenate by earthworms from water and soil.

Toxicity values were obtained for pentachlorophenol (PCP) and other compounds in the standard OECD and EEC earthworm test. To help explain the uptake and bioaccumulation mechanisms of PCP which affect toxicity, experiments have been conducted using the earthworm Allolobophora caliginosa. The experiments showed that radiolabelled PCP and its sodium salt, PCP-Na, were taken up rapidly by the earthworms during 24 h from aqueous solution (1 and 10 micrograms ml-1) in a limited volume (5 ml) to give a bioconcentration factor (BCF) of 2.5, and that the solution concentration had no apparent influence on uptake. Exposure of worms over a period of 14 days in a large volume of soil under laboratory conditions increased the BCF, which was approximately 8 and 13 in the low (2.2 mg g-1 soil) and high (11.2 mg g-1 soil) soil concentration respectively. Longer exposures of the same worm species for 131 days in another soil type, in lysimeters under outdoor conditions, did not increase the BCF beyond that reached after 14 days exposure in the artificial soil. There were differences between earthworm species in their bioconcentration ability: Lumbricus terrestris accumulated 3 times more radiocarbon than A. caliginosa. Irrespective of the concentrations in solution, the binding of free phenol (PCP) in worm tissues was greater than for its sodium salt (PCP-Na), but there were no apparent differences in the amount of these substances eliminated, which was rather low. Metabolic studies have shown that PCP is metabolised more rapidly than PCP-Na in the worms body, resulting in the formation of metabolites which are polar in nature and also probably of conjugates. The results are discussed in relation to the mechanisms which may be responsible for the detoxification of PCP in earthworms.

Animals↗

PubMed1992

Validation of earthworm toxicity tests by comparison with field studies: a review of benomyl, carbendazim, carbofuran, and carbaryl.

To investigate whether results of laboratory toxicity tests with earthworms are capable of being used to predict effects in the field, a literature study was carried out. Benomyl, its metabolite carbendazim, carbofuran, and carbaryl were chosen as model substances. From data on the behavior of these pesticides in soil, it can be concluded that shortly after application most of the dosage will be in the top 2.5-cm soil layer. Soil concentrations can be estimated from field dosages used. Estimated field soil concentrations that affected earthworm populations were in agreement with effect levels determined in laboratory studies. In the field, species living in the surface layers (e.g., juveniles of many species) or coming to the soil surface to feed (e.g., Lumbricus terrestris) are most affected, since they experience a high degree of exposure. Evidently, species having long generation times need a relatively long time to recover. Both the distribution of the pesticide and the behavior of earthworms in soil affect earthworm exposure. Insight into these aspects may provide tools to predict both short- and long-term effects of pesticides on earthworm populations in field soils.

Animals↗

PubMed1993

Molecules in earthworm coelomic fluid that bind anti-IgA and anti-IgG, but not anti-IgM.

Coelomic fluid from the earthworm Lumbricus terrestris is known to contain immunoactive cells and molecules involved in immune defense. To assess the ability of such molecules to form precipitating complexes with anti-human immunoglobulins, radial immunodiffusion experiments were conducted. Anti-human IgG, anti-human IgA, and anti-human IgM were the three immunoglobulins examined. Earthworm coelomic fluid was found to contain molecules that bind anti-IgA and anti-IgG. No precipitation reactions were observed with anti-IgM. Earthworm coelomic fluid diluted 1:8 still formed precipitating complexes with anti-IgA and anti-IgG. Elucidation of the earthworm binding site on anti-IgG and anti-IgA could make earthworm coelomic fluid a valuable reagent in immunological, chemical and biological research.

Animals↗

PubMed1995

Earthworm communities along a gradient of urbanization.

Earthworms were studied at six sites along a gradient of urbanization and their relations with several soil abiotic factors were determined. Concentrations of heavy metals, calcium and magnesium in earthworms and in soils were measured by atomic absorption spectroscopy. Strong negative correlations were detected between earthworm density and soil concentrations of cadmium and magnesium. Earthworm biomass was negatively correlated with lead, copper and zinc, and positively correlated with the distance from the centre of the city. High concentrations of Cd and Zn (concentration factors 49 and 32) were accumulated by earthworms in contrast to those of Cu and Pb (2 and 1). Relations between worm and soil concentrations of heavy metals, Ca and Mg are discussed.

Journal Article↗

PubMed1991

Experimental infection of Japanese quail with Toxocara canis larvae through earthworms.

The migration and distribution of Toxocara canis larvae in the tissues of earthworms exposed to 5 x 10(5) infective eggs in soil, as well as the reinfectivity of the larvae in Japanese quail fed with three earthworms, were studied. The average number of larvae recovered from an earthworm gradually declined from 9 +/- 3.21 to 4.5 +/- 2.00 at 4-16 days. No larvae were recovered at Day 20. When compared between three portions of the earthworms' body, the middle part showed the greatest recovery in comparison with the anterior and posterior parts. At necropsy, the average larval burden of quail at 15 days post-infection was 6 +/- 3.60 in the liver and no larvae were recovered from other tissues. The role of the earthworm in relation to paratenism is discussed.

Animals↗

PubMed2005

Transcriptome analysis in the midgut of the earthworm (Eisenia andrei) using expressed sequence tags.

In order to gain insight into the expression profiles of the earthworm midgut, we analyzed 1106 expressed sequence tags (ESTs) derived from the earthworm midgut cDNA library. Among the 1106 ESTs analyzed, 557 (50.4%) ESTs showed significant similarity to known genes and represented 229 unique genes of which 166 ESTs were singletons and 63 ESTs manifest as two or more ESTs. While 552 ESTs (49.9%) were sequenced only once, 230 ESTs (20.8%) appeared two to five times and 324 ESTs (29.3%) were sequenced more than five times. Considering this redundancy of expression, it is likely that the gene expression profile of the earthworm midgut would be polarized. The expression of globin-related proteins, including ferritin and linker chain, and fibrinolytic enzymes appeared to account for 10.1% and 4.7% of the total ESTs analyzed in this study, respectively. This suggests that the prime functions of the midgut in the earthworm would be associated with protein hydrolysis as well as globin formation. Among the recognized protein-coding genes, the gene category involved in protein synthesis appeared to be the largest one accounting for 15.6% of the expression in the midgut, followed by gene categories associated with energy (11.2%), homeostasis (10.8%), metabolism (3.6%), cytoskeleton (2.5%), and protein fate (1.4%). With regard to functional aspects, the most abundantly expressed genes were associated with respiratory pigment (10.1%), cellular respiration (8.6%), and fibrin hydrolysis (4.7%). In addition, we were able to identify novel ESTs in the earthworm, which were related to the innate immune system, including destabilase, a possible antagonist of transglutaminase.

Animals↗

PubMed2004

Toxicity and bioaccumulation of reduced TNT metabolites in the earthworm Eisenia andrei exposed to amended forest soil.

Soils contaminated with 2,4,6-trinitrotoluene (TNT) and TNT primary reduction products have been found to be toxic to certain soil invertebrates, such as earthworms. The mechanism of toxicity of TNT and of its by-products is still not known. To ascertain if one of the TNT reduction products underlies TNT toxicity, we tested the toxicity and bioaccumulation of TNT reduction products. 2-Amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), 2,4-diamino-6-nitrotoluene (2,4-DANT) and 2,6-diamino-4-nitrotoluene (2,6-DANT) were tested separately in adult earthworms (Eisenia andrei) following a 14-d exposure to amended sandy loam forest soil. TNT, 4-ADNT, and 2-ADNT were lethal to earthworms (14-d LC(50) were: 580, 531 and 1088 micromol kg(-1), or 132, 105 and 215 mgkg(-1) dry soil, respectively) and gave the following order of toxicity: 4-ADNT>TNT>2-ADNT. Exposure to 2,4-DANT and to 2,6-DANT caused no mortality at 600 micromol kg(-1) or 100 mgkg(-1) dry soil. We found that all four TNT reduction products accumulated in earthworm tissues and 2-ADNT reached the highest levels at 3.0+/-0.3 micromol g(-1) tissue. The 14-d bioaccumulation factors were 5.1, 6.4, 5.1 and 3.2 for 2-ADNT, 4-ADNT, 2,4-DANT and 2,6-DANT, respectively. Results also suggest that some TNT metabolites are at least as toxic as TNT and should be considered when evaluating the overall toxicity of TNT-contaminated soil to earthworms.

Analysis of Variance↗

PubMed2005

Effect of earthworms (Eisenia fetida) on the fractionation and bioavailability of rare earth elements in nine Chinese soils.

The effect of earthworm (Eisenia fetida) activity on soil pH, dissolved organic carbon (DOC), fraction distribution pattern and bioavailability of rare earth elements (REEs) Y, La, Ce, Pr and Nd in nine Chinese soils were investigated using pot experiments. A three-step extraction procedure recommended by the European Community (Standards, Measurements and Testing Programme) was used to fractionate REEs in soils into water soluble, exchangeable and carbonate bound (B1), Fe- and Mn-oxides bound (B2) and organic matter and sulfide bound (B3). Inoculated with earthworms, the soil pH, DOC and water-soluble rare earth elements fraction increased. A significant correlation was obtained between the increased DOC and the increased water-soluble REEs. REEs in fraction B1 increased after earthworm inoculation, while those in fraction B3 decreased. No significant differences were observed for REEs in fraction B2. The biomass and the concentrations of REEs in wheat shoots and roots increased after the treatment with earthworms. The results demonstrated that earthworm activity increased the mobility and bioavailability of REEs in soils.

Animals↗

PubMed2005

Avoidance of Cu- and Zn-contaminated soil by three ecologically different earthworm species.

Earthworm avoidance response to soils contaminated with harmful substances has been proposed as a potential tool for assessing soil toxicity with low test effort. In the present study, the objective was to find out whether three ecologically different earthworm species, Aporrectodea tuberculata (Eisen), Lumbricus rubellus (Hoffmeister), and Dendrobaena octaedra (Savigny), avoid soils simultaneously spiked with Cu and Zn. In addition, metal-contaminated field soil taken close to a Cu-Ni smelter was tested with A. tuberculata using a two-section avoidance lest procedure. All three earthworm species clearly avoided Cu/Zn contaminated soil but differently: D. octaedra was the most sensitive species, responding to low metal concentrations, whereas L. rubellus responded only to the highest metal concentration tested, being the least sensitive species. Moreover, A. tuberculata showed clear avoidance response to the metal contaminated field soil. In conclusion, the results indicate that earthworm avoidance behavior is an ecologically relevant parameter for assessing harmfulness of metal contaminated soils, both spiked and field-contaminated soils. However, it is important to consider the specific species to be used in the earthworm avoidance test procedure.

Animals↗

PubMed2005

The use of earthworms in ecological soil classification and assessment concepts.

Without doubt, earthworms are the most important soil invertebrates in most soils worldwide, in terms of both biomass and activity. Several species are even considered to be ecosystem engineers. Earthworms are also known to influence soil structure, soil chemistry, and, in particular, processes like organic matter decomposition. In addition, standardized sampling methods are available and their taxonomy is well known (even the first PC-aided keys have been developed). For these reasons, earthworms were recognized as a part of ecological classification and assessment schemes early on. However, due to the relatively small number at many sites, they have to be part of a battery approach. By use of examples from The Netherlands (biological indicator of soil quality) and Germany (soil biological site classification), the practicability of the use of earthworms is demonstrated in determining the influence of different anthropogenic land use forms. In these cases, the structure of the earthworm community, as well as their abundance and biomass, were used as endpoints.

Animals↗

PubMed2004

Earthworm biomass as additional information for risk assessment of heavy metal biomagnification: a case study for dredged sediment-derived soils and polluted floodplain soils.

The important role of earthworms in the biomagnification of heavy metals in terrestrial ecosystems is widely recognised. Differences in earthworm biomass between sites is mostly not accounted for in ecological risk assessment. These differences may be large depending on soil properties and pollution status. A survey of earthworm biomass and colonisation rate was carried out on dredged sediment-derived soils (DSDS). Results were compared with observations for the surrounding alluvial plains. Mainly grain size distribution and time since disposal determined earthworm biomass on DSDS, while soil pollution status of the DSDS was of lesser importance. Highest earthworm biomass was observed on sandy loam DSDS disposed at least 40 years ago.

Animals↗

PubMed2005

Uranium contents and (235)U/(238)U atom ratios in soil and earthworms in western Kosovo after the 1999 war.

The uranium content and (235)U/(238)U atom ratio were determined in soils and earthworms of an area of Kosovo (Djakovica garrison), heavily shelled with depleted uranium (DU) ammunition during the 1999 war. The aim of the study was to reconstruct the small-scale distribution of uranium and assess the influence of the DU added to the surface environment. The total uranium concentration and the (235)U/(238)U ratio of topsoils showed great variability and were inversely correlated. The highest uranium levels (up to 31.47 mg kg(-1)) and lowest (235)U/(238)U ratios (minimum 0.002147) were measured in topsoils collected inside, or very close to, the clusters of DU penetrator holes. Regarding the fractionation of uranium in the surface soils, the uranium concentrations in the soluble and exchangeable fractions increased as the total uranium concentration of the topsoils increased. High and rather uniform percentage contents of uranium (24-36%) were associated with the poorly crystalline iron oxide phases of soils. In the U-enriched soils the elevated levels of the element were probably due to the presence of very small, unevenly distributed oxidized DU particles. The total uranium concentration in earthworms was in the range 0.142-0.656 mg kg(-1), with the highest concentrations in Lumbricus terrestris. The juveniles of all three studied species seemed to accumulate uranium more than adults, probably due to age-related differences in metabolism. The (235)U/(238)U ratio in the earthworms was variable (0.005241-0.007266) and independent of both the total uranium contents in soils and the absolute uranium levels in the animals. Bioconcentration was greater at lower U concentrations in soil, probably due to an increasing rate of elimination of uranium by the earthworms as the soil contents of the element increase. The results of this study clearly indicate that DU was added to the soil of the study area. Nevertheless, the phenomenon was very limited spatially and the total uranium concentrations fell within the natural range of the element in soils. Moreover, the absolute uranium concentrations indicate that there was no contamination of the earthworm species studied.

Animals↗