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Phosphorus availability and acid pH are major limiting factors for grass and crop production in the Andisols of Southern Chile. Sustainable management requires both the efficient use of fertilizers...

Digestates, a byproduct of the anaerobic bioconversion of organic wastes for the production of biogas, are highly variable in chemical and biological properties, thus limiting their potential use in agriculture as soil amendment. Using a lab-scale glass reactor, we aimed to assess the feasibility to chemically stabilize the solid fraction of an anaerobic digestate by applying a Fenton reaction under constant pH (3.0), temperature (70 °C), reaction time (8 h), and various combinations of H2O2 and Fe2+. In Fenton-treated samples, the phytotoxic potential (determined on a test plant), total phenols, and the bad smell odor index markedly declined, whereas total C and N remained unaltered. Thermogravimetric (TG) analysis and Fourier transform infrared (FT-IR) spectroscopy revealed contrasting changes in extracted humic and fulvic fractions being increased or depleted, respectively, in aromatic substances. Process feasibility and optimum conditions for an effective biomass stabilization were achieved with a H2O2/Fe2+ ratio between 0.02 and 0.03.

Soil organic matter (SOM) plays an important role in conservation and restoration of soil fertility, as it is able to ameliorate physical, chemical and biochemical soil properties preventing erosion, increasing porosity, water-holding capacity and cation exchange capacity. Furthermore, SOM can stimulate microbial biomass and as consequence microbial activity and functionality in terms of soil respiration and enzymatic activities. Biogeochemical cycle of nutrients can also take advantages from the microbial activity enhancement with positive effects on N and P uptake and crop yields. The intensive farming systems favour the SOM decomposition and depletion due to the absence of rotations, the preference of milling to ploughing, the mineral fertilization, and the removal of crop residues.The aim of this research was to assess the effect of vermicompost (VC) as organic soil conditioner compared to pelleted manure (PM) under greenhouse in a conventional farm. Two doses of VC and PM corresponding to 75 and 150 kg N ha-1 year-1 were applied to solarized soil. Solarization was carried out during the hottest summer period and applied to all plots to control weeds, nematodes and soil-borne pathogens. VC is the final product of a vermicomposting process involving synergistic action of earthworms and microbes in the bio-conversion of organic matter into humus-like substances. VC used in this research derived from solid digestate obtained in anaerobic digestion plant using, as carbon source, livestock sewage, olive mill wastewater and whey from dairy industry. Chemical and biochemical properties of soils sampled after 7 and 150 days from organic amendments were investigated to understand the correlation between the use of organic soil conditioners and organic C stock, nutrient availability, microbial biomass, enzymatic activity, and crop yields and quality.In the first sampling PM increased significantly the soil electrical conductivity compared to VC amendments. In addition, PM, in particular the greater dose, enhanced better than VC soil respiration, microbial biomass and overall enzymatic activities because PM is richer in labile carbon source than VC. In contrast, VC was able to improve the activity of acid phosphatase and urease by increasing the applied dose thus making free phosphate and ammonium from organic matter.This study is part of the project "Sustainable management of soil fertility in the Sele Plain to produce ready-to-eat food as cover crops through organic amendment deriving from local livestock sector" funded by PSR Campania 2014/2020.

Aims: In a hypertensive population with optimal blood pressure control with a long-term follow-up, we aimed at analysing possible predictors of left ventricular (LV) ejection fraction (LVEF) reduction, including indexed mechano-energetic efficiency (MEEi), a well-recognized echo-derived parameter of LV performance. Methods and results: The study population included 5673 hypertensive patients from the Campania Salute Network with a long-term follow-up, normal baseline LVEF (≥50%), and no prevalent cardiovascular (CV) disease. Patients developing LVEF impairment (LVEF

Background Lemon processing procedures yield a significant amount of waste as peels, which are 57% of processed lemons and represent a possible source of bioactive compounds (essential oils, EOs). EOs were extracted from lemon fruits belonging to four cultivars harvested at four different sampling times (25 October, 23 November, 20 December, 1 February), characterized, and quantified through gas chromatography-mass spectrometry. Results The chemical composition of EOs highlighted that 26 compounds of the four lemon cultivars at the different ripening stages were clearly identified. The compounds analysed belonged to four chemical classes: monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes, and fatty alcohol esters. Among the monoterpene hydrocarbons, d-limonene, β-pinene, and γ-terpinene were the most abundant; and among the oxygenated monoterpenes, α-terpineol, nerol, and geraniol were the most abundant. Quantitative gas chromatography-mass spectrometry analysis of the most abundant monoterpene hydrocarbons (α-pinene, β-pinene, myrcene, d-limonene, and γ-terpinene) highlighted that the amount of EOs decreased during ripening stages. 'Ovale di Sorrento' and 'Sfusato Amalfitano' showed the highest level of EOs in December, whereas in 'Femminello Cerza' and 'Femminello Adamo' this occurred in November. EOs, as well as the phenolic compounds, were positively correlated with the antioxidant activity (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid). Conclusions EOs reached the highest level in the four lemon cultivars at different ripening stages. Campanian cultivars ('Ovale di Sorrento' and 'Sfusato Amalfitano') showed the greatest EO content in November, whereas in Sicilian cultivars ('Femminello Cerza' and 'Femminello Adamo') this occurred in December. Besides phenolic compounds, measured in lemon peel extracts, EOs can contribute to antioxidant activity, as demonstrated by the positive correlation. © 2019 Society of Chemical Industry.

Anaerobic digestion (AD) of organic wastes is a promising alternative to landfilling for reducing greenhouse gas emission and it is encouraged by current regulation in Europe. AD represents a source of green energy, while the by-product digestate still generates concerns for a safely disposal. The sustainability of AD plants partly depends on the management of digestion residues. Digestate could be used in organic amendment straightaway or after composting to limit possible phytotoxicity effects on crops. This study has been focused on the environmental benefits of digested olive mill wastewater (OMW), recalcitrant agricultural waste. OMW require a complex management due to high production volume in a limited time, fermentative processes occurring during the storage, and toxicity due to phenol compounds. These latter might compromise the AD process affecting microbial metabolism. As biochar is able to adsorb and retain organic and inorganic pollutants, we used biochar as additives during AD to remove phenols, stimulate microbial activity and therefore hydrogen and methane production. The resulted digestates including biochar could be used in order to increase the carbon stock in soil as a valid alternative to other organic amendments.The aim of this work was to evaluate the effect of solid and liquid digestates, obtained from the AD process of OMW with biochar (30 and 45%), as additive, on soil chemical and biochemical properties in order to validate its use in organic amendment in lab-scale experiment. The liquid and solid digestates were added to soil according to the maximum dose allowed by the Italian nitrates directive concerning non-vulnerable areas (91/676/EEC, DGR 209/2007). Pots containing soil differently amended with liquid and solid digestates were prepared also for the growth of Lactuca sativa L. seedlings.Thirty days after treatments, positive changes in chemical and biochemical properties in soil pots with biochar-treated digestates, in particular with liquid ones, occurred. Soil organic carbon, microbial biomass carbon and some soil enzymatic activities such as dehydrogenase, phosphomonoesterase, β-glucosidase and fluorescein diacetate hydrolysis significantly improved. Besides an enhancement of lettuce biomass, a significant decrease of nitrate content in plant tissue was registered when pots were amended with biochar-treated digestates.The assessment of the agronomic quality of liquid and solid digestates, obtained by biochar assisted AD of OMW, as organic soil amendment, demonstrated that also critical biomass such as OMW, if opportunely treated, can entry in a re-use process where biogas and by-products can be part of virtuous circular economy.This work was part of the project “Mitigation of the environmental impact of olive mill waste water through sustainable bioprocess with energy recovery” funded by the Università degli Studi di Napoli Federico II.

Intensive cultivation of greenhouse crops can damage soil quality due to higher micro-environmental temperatures than field crop production, the absence of rotations, the preference of milling to ploughing, the mineral fertilization and the removal of crop residues without the organic matter reintegration. The compost addition to agricultural soil mainly enhances the organic matter content having, in turns, effects in improving physical, chemical, biochemical and microbiological soil properties, preventing erosion, increasing water holding capacity, cation exchange capacity, nutrient absorption by plants. Further a progressive carbon sequestration in soil with the consequent mitigation of climate changes occurs whereas the non-use of organic fertilizers produces a loss in C stock in soil as carbon dioxide in the atmosphere. The degradation of soil quality is reflecting on the crop yields of the ready-to-eat food of the Plain of Sele river in Campania region in South Italy.Objectives of this research was to assess the short-term effect of vermicompost as organic soil conditioner in place of other organic fertilizers under conventional farming. Vermicompost derived from digestate obtained in anaerobic digestion plant of the Plain of Sele using, as ingestate, livestock sewage, olive mill wastewater and whey from dairy industry. Soil solarization was carried out during the summer to control weeds and soil pathogens. The chemical and biochemical properties of soils sampled after 4 days from soil amendment were investigated to determine the correlation between the use of vermicompost as organic soil conditioner and C stock, nutrient availability, and crop yields. Solarization negatively affected soil respiration and overall enzymatic activities compared to plots without the treatment. Vermicompost as well as pellet, used as other organic soil conditioner, increased soil respiration only in not solarized plots. Conversely no significant changes in term of microbial biomass carbon among treatments occurred. Different responses in terms of crop yields of rocket were observed in plots cultivated under diverse treatment: solarized plots produced greater amount of rocket than not solarized plots and plot amended with vermicompost showed the best performance among solarized ones.This work was part of the project “Sustainable management of soil fertility in the Sele Plain to produce ready-to-eat food as cover crops through organic amendment deriving from local livestock sector” funded by PSR Campania 2014/2020.

Citrus limon (L.) Burm contains many important natural bioactive compounds, such as ascorbic acid, essential oils, and antioxidant substances. An experiment was carried out on four lemon cultivars (Ovale di Sorrento, Sfusato Amalfitano, Femminello Cerza and Femminello Adamo) from Southern Italy to study the changes in physico-chemical properties of juice during fruit ripening. Morphological characteristics of fruits, total soluble solids, pH and titratable acidity, ascorbic acid (AsA), and antioxidant activity (TEAC) of juice were tested. The concentrations of AsA in lemon juice showed significant differences among cultivars and ripening stages, with a steadily decrease along ripening stages: from 31.38 of stage I to 23.71 mg 100 g−1 of stage IV. The juice AsA concentration correlated with the colorimetric parameters of peel: L (r = −0.643), a (r = −0.719) and b (r = −0.654). The cv Ovale di Sorrento showed the highest average AsA concentration (29.91 mg 100 g-1). The level of the total TEAC showed a significant steadily decrease from the first to the fourth ripening stage that on average approached 38 %. Principal component analysis showed that lemon fruits at the ripening stages II and III were highly similar each other and well discriminated from the first and last ripening stages that also performed more distantly each other. The paper provides in-depth knowledge about the trend in AsA content and antioxidant activity of lemon juice across ripening.

Pentachlorophenol (PCP) is quite persistent in the environment and severely affects different ecosystems including forest soil. The main objective of this work was to study different bioremediation processes of artificially PCP (100 mg kg-1) contaminated forest soil (Sc). In fact, we used bioaugmentation by adding two different bacterial consortia B1 and B2, biostimulation procedures by amendments based on forest compost (FC), municipal solid waste compost (MC), sewage sludge (SS), and phosphate, and their combined treatments. Soil physical and chemical properties, residual PCP, soil microbial biomass carbon, soil respiration and some enzymatic activities at zero time and after 30 d of incubation, were evaluated. A net reduction of PCP, 71% of the initial concentration, after 30 d-incubation occurred in the sample Sc+B1+FC, as the best performance among all treatments, due to natural attenuation, immobilization of PCP molecules in the forest soil through organic amendments, and the action of the exogenous microbial consortium B1. The single application of FC or B1 led to a depletion of PCP concentration of 52% and 41%, respectively. Soil microbial biomass carbon decreased in PCP contaminated soil but it increased when organic amendment also in combination with microbial consortia was carried out as bioremediation action. Soil respiration underwent no changes in contaminated soil and increased under FC based bioremediation treatment. These results demonstrate that the combined treatments of biostimulation and bioaugmentation might be a promising process for remediation of PCP contaminated soil.

Carrot (Daucus carota L.) is a widely consumed root vegetable, whose growth and safety might be threatened by growing-medium arsenic (As) contamination. By this work, we evaluated the effects of humic acids from Leonardite and NPK mineral fertilisation on As mobility and availability to carrot plants grown for 60 days in a volcanic soil irrigated with As-contaminated water - representing the most common scenario occurring in As-affected Italian areas. As expected, the irrigation with As-contaminated water caused a serious toxic effect on plant growth and photosynthetic rate; the highest rate of As also inhibited soil enzymatic activity. In contrast, the organic and mineral fertilisation alleviated, at least partially, the toxicity of As, essentially by stimulating plant growth and promoting nutrient uptake. The mobility of As in the volcanic soil and thus its phytoavailability were differently affected by the organic and mineral fertilisers; the application of humic acids mitigated the availability of the contaminant, likely by its partial immobilisation on humic acid sorption sites - thus raising up the intrinsic anionic sorption capacity of the volcanic soil; the mineral fertilisation enhanced the mobility of As in soil, probably due to competition of P for the anionic sorption sites of the soil variable-charge minerals, very affine to available P. These findings hence suggest that a proper soil management of As-polluted volcanic soils and amendment by stable organic matter might mitigate the environmental risk of these soils, thus minimising the availability of As to biota.

INTRODUCTION: Hantavirus diseases are emerging human diseases caused by Hantavirus spp. of the Bunnyaviridae family. Hantavirus pulmonary syndrome (HPS) has been detected in the Federal District (DF) of Brazil since 2004. Among the 27 Brazilian Federal Units, DF has the highest fatality rate. More than 10 years have already passed since then, with confirmation of cases caused by the Araraquara and Paranoa species. The reservoir is Necromys lasiurus. METHODS: Local surveillance data of the confirmed cases were analyzed, including age, sex, month and year of occurrence, clinical symptoms, syndromes and outcomes, and probable transmission place (PTP). The cases were mainly confirmed by IgM detection with a capture enzyme immunoassay. The cases were classified as autochthonous if PTPs were in the DF area. RESULTS: From 2004 to 2013, in the DF, 126 cases of hantavirus were confirmed, and the cumulative incidence was 5.0 per 100,000 inhabitants. The occurrence of cases was predominantly from April to August. At least 75% of the cases were autochthonous. Acute respiratory failure was reported in 47.5% of cases, and the fatality rate was 40%. CONCLUSIONS: In the DF, the cumulative incidence of HPS was one of the highest worldwide. A seasonal pattern of hantavirus disease in the dry season is clear. There was a high frequency of severe clinical signals and symptoms as well as a high fatality rate. For the near future, visitors and inhabitants of DF rural areas, particularly male adults, should receive continuous education about hantavirus transmission and prevention.

INTRODUCTION: Human leptospirosis (HL) in the Federal District (DF), Brazil, is endemic and requires studies to characterize the socio-epidemiological profile of the vulnerable population. METHODS: Seventy-nine autochthonous cases of HL between 2011-2015 were analyzed based on the databases of the Epidemiological and Environmental Health Surveillance Department, DF. RESULTS: The male population aged 31-45 years represented 86% of the leptospirosis cases; most belonged to the social classes D and E. CONCLUSIONS: In the DF, preventive measures should be concentrated on economically active male adults of social classes C, D, and E with the aim of promoting health.

Summary Intensive agricultural systems negatively affect soil quality principally because of a reduction in soil organic matter (OM). Sustainable practices providing organic amendments could be useful to maintain or increase OM content in agricultural soils, preserving and improving soil fertility. In this study, biomass with a large C:N ratio was applied to intensively farmed agricultural soils to maximize the increase of soil OM and hence chemical and biochemical fertility. In particular, 30 and 60 t ha−1 of two mixtures of compost and scraps from poplar pruning, A1 and A2, with different C:N ratios (15 and 25, respectively), were applied to soils of two farms (F1 and F2) in a Mediterranean area (southern Italy) on an annual basis for two consecutive years. An effective, long-lasting increase of soil OM, on average of 60 and 55% in F1 and F2 soils, respectively, was reached at the end of the experiment. As well as a progressive increase in the C:N ratio, total N and available P also increased with organic amendments, with positive effects on soil microbial activity as demonstrated by the enhancement of the seven studied enzymatic activities. Principal component analysis demonstrated different responses to various organic amendments between F1 and F2 soils because of their geopedological diversity. The results indicate that the C:N ratio of the mixture is an important factor, but what is the best rate of addition to use is still not obvious. The use of a smaller amount (30 t ha−1) of the A1 mixture (10:1 compost:wood) appears, in these types of soils, to be the most suitable strategy to produce significant benefits.

INTRODUCTION: Leptospirosis is an infectious disease that affects more than 5,000 people per year in Brazil. The Federal District (FD) lacks epidemiological studies of human leptospirosis and presents concerning rates of this disease, especially considering its lethality. METHODS: Seventy-nine autochthonous human cases of leptospirosis between 2011 and 2015 were analyzed, with the probable infection location serving as a basis for the collection and analysis of the environmental and epidemiological variables. RESULTS: The incidence of the disease ranged from 0.68-13.39 per 100,000 inhabitants in 21 of the 31 administrative regions that compose the FD. The local profile of human leptospirosis was predominantly associated with urban areas during the rainy season, population access to the sewage network, the treated water network, and the public garbage collection service. The vast majority of cases had a strong association with synanthropic rodents at the infection sites. CONCLUSIONS: In order to prevent and control potentially lethal human leptospirosis infection, the eco-epidemiological characterization of this disease is a valuable tool for public policies of prevention, control, and surveillance. In addition to population awareness, the systematized control of synanthropic rodents could be the main health action to reduce the incidence of this disease in the FD.

Background and aims Litter decomposition is a critical process in terrestrial ecosystems and understanding the effects of soil fertility on the litter decay rate is of great ecological relevance. Here we test the hypothesis that N transfer from soil to litter will promote the decay rate of N poor but not N rich litter types. Methods Ten organic substrates, encompassing a wide range of biochemical quality in terms of C/N and lignin/N ratios, were decomposed in microcosms over three soil types with different N content, but inoculated with the same microbiome. Organic substrates were characterized for mass loss, C and N content to assess N transfer from soil to litter. Results The decay rate response to soil fertility was related to their initial N content: positive for substrates with little initial N content and not significant for N rich plant residues. A significant N transfer, generally larger from N rich soil to N poor substrates, was found. Litter C/N and lignin/N ratios showed variable relationships with the litter decay according with the soil fertility gradient, with positive and negative correlations in N rich and N poor soils, respectively. Conclusions Our study demonstrated that the decomposition of N rich litter proceeded irrespective of soil fertility while the decay rate of N poor substrates, either lignin poor or rich, was controlled by soil fertility likely as a result of N transfer. Litter C/N and lignin/N ratios were reliable indicators of litter quality to predict their decay rate in N poor soil, but not in N rich soils.

Phenanthrene (Phe) and pentachlorophenol (PCP) are classified as persistent organic pollutants and represent serious concern for the environment as they are toxic and ubiquitous. Biochar based remediation is an emerging technology used in water and soil contamination. In this study we used poplar (BP) and conifer (BC) biochars to remediate water and soil contaminated by Phe and PCP. BP and BC were able to remove completely either Phe or PCP from contaminated water within one to three days. When biochar was confined in a porous membrane, BC and BP maintained their sorption efficiency for several remediation cycles. However, in these conditions BC allowed faster Phe removal. In soil remediation experiments, addition of two biochar rates, i.e. 2.5 and 5 mg g−1, strongly reduced Phe extractability (up to 2.7% of the initially added Phe with the larger BC dose). This was similar to the behavior observed when compost was applied in order to verify the role of soil organic matter in the fate of both contaminants. PCP extractability was reduced only up to 75% (in average) in all samples including those with compost amendment. Only larger amount of biochar (20 and 50 mg g−1) allowed reduction of the extractable PCP and nullified phytotoxicity of the contaminant.

Soil biodiversity and in particular soil microbial and enzymatic diversity are of paramount importance for assuring and maintaining a healthy soil. Any event that can impair them may alter, even irreversibly, the quality of soil and consequently the safety of environment and human life. Xenobiotic substances, i.e., foreign chemical substances of different chemical and structural complexities, not recognized by existing degradative enzymes, have been released into the environment by several industrial and/or agricultural activities. When reach soil, they may accumulate in it because several of these chemicals are recalcitrant and resist to any kind of degradative transformation. Negative effects on the life and functioning of microbial organisms may derive. Several investigations have been devoted to understanding the effect of xenobiotics on soil microorganisms and enzymes by using traditional and advanced methodologies. This chapter will briefly survey the mutual interactions establishing in soil among xenobiotic substances and microbial and enzymatic soil activities.

Location and stability of a recombinant prion protein (recPrP) and its interaction with humic-like complexes were investigated by low-temperature ashing (LTA), thermal gravimetric (TG), and scanning electron microscopy (SEM) analyses. Humic-like complexes were obtained by abiotic polymerization of catechol, one of the possible precursors of soil humic matter, through the catalysis of birnessite, a manganese oxide common in soil environment. The recPrP was immobilized in organomineral complexes via sorption or entrapment. Complexes were treated by LTA, allowing the controlled removal of organic matter layer by layer, from the external to the internal side, with minimal disturbance of mineral constituents. Thermal gravimetric and SEM analyses were performed on specimens before and after LTA treatment. Entrapped recPrP, compared with sorbed, resulted less easily accessible to LTA treatment and showed a higher thermal stability by TGA analyses. On the basis of these findings, we hypothesize that the processes leading to newly formed organic complexes can enhance prion stability in soil and thus influence the environmental diffusion of infectivity.

Olive Mill Wastewater (OMW), a C-rich organic waste with high contents of both toxic phenols and valuable nutrients, is yearly produced in large amounts in the Mediterranean area. A possible recycling option is to spread it on agricultural land, provided that phytotoxic effects are neutralized. Research studies were performed on the use of OMW for soil fertigation in a laboratory model system. It consisted of a soil, representative of lands with dramatic water deficiency and very poor in organic matter content, supplied with a given amount (80 m3 ha−1) of OMW as such (crude OMW, c-OMW) and after the removal of its toxic phenolic compounds (dephenolized OMW, d-OMW). Dephenolized OMW was produced in a soil-slurry stirred reactor containing an agricultural soil as catalyst. Several biochemical properties as well as the residual phytotoxicity of the soil with and without the two OMW amendments were monitored over time (0–42 days). The tested enzymes, as well as the microbial and chemical soil properties, showed different patterns in response to both crude and dephenolized OMW addition and time of incubation. As a general response several properties of the soil, mainly biological, changed suddenly or at the most within 0–14 days after the addition of the both kinds of OMW. Thereafter, most of them returned to their original values, showing the soil's resilience capability. As compared to c-OMW amendment, the addition of d-OMW to the soil resulted in a smaller impact onto soil performance as attested by the complete recovery of the soil germination capability, a less inhibitory effect of some enzymatic activity (urease) and higher values of the respiratory quotient qCO2. The application of OMW, mainly after removal of its phenolic components, may be suggested as a good strategy for restoring soils in semiarid area and poor in organic matter.

In the Mediterranean region, difficult climate conditions and inadequate land management have led to a reduction of the organic matter content of soils. As a solution, municipal solid waste (MSW) compost and sewage (S) sludge were investigated for their effectiveness in maintaining soil fertility. Clayey-loamy soil was amended with 0, 40, and 80 t ha -1 of MSW compost or S sludge and cultivated with Triticum durum. Soil was sampled 15 and 70 days after sowing, and the activities of arylsulphatase, phosphatase, dehydrogenase (DH), β-glucosidase (β-GLU), urease, and catalase (CAT) were assayed. The wheat was harvested after 68 days, then soil properties as well as plant growth and K + and Na + contents were determined. Almost all soil enzymatic activities were significantly (P < 0.01) affected by amendment dose, sampling time, and their interaction. At 15 days, MSW compost had a moderate effect on DH, β-GLU, and CAT activities under both applied doses. A significant increase of all the measured activities was observed after 70 days at either 40 t ha -1 or 80 t ha -1 (ranged between 16%-160% and 10%-81%, respectively), likely providing a long-term nutrient release. The activities of arylsulphatase, phosphatase, DH, CAT, and β-flu (only with the lower dose) were strongly enhanced at 15 days after S sludge treatment. After 70 days, an increase of the enzymatic activities occurred with S sludge, although its beneficial effect was reduced mainly at 80 t ha -1 presumably because of the presence of micropollutants in the sludge. Plant growth was significantly improved by 40 and 80 t ha -1 of compost (93% and 126%, respectively); however, less impact was observed with S sludge. Overall, the results suggest that addition of MSW compost could enhance the fertility of degraded soils and promote plant growth.

INTRODUCTION: Visceral leishmaniasis is a public health threat in Brazil considering the high lethality rates and increasing geographical dispersion to large urban conglomerates over the past 25 years. This study aimed to confirm suspected autochthonous cases of visceral leishmaniasis reported from 2005 to 2009 among individuals living in Brasilia, Federal District. METHODS: A retrospective review of the surveillance data obtained on a regular basis and clinical records of the reported cases were performed in 2009. RESULTS: Data from entomological and canine surveys revealed the presence of both Lutzomyia longipalpis and positive serology for Leishmania in dogs within 19 of the 21 neighborhoods where human cases occurred since 2005. The review of surveillance data and medical records, together with the entomological and canine survey data, permitted confirmation of 21 autochthonous human cases in the Federal District. The disease predominantly affected children (12/21) and those from the Sobradinho region (16/21); the typical presentation of fever, hepatosplenomegaly and pancytopenia was observed in 67% of cases. Three deaths occurred during the study period. Leishmania (Leishmania) chagasi was successfully isolated from one human case and twelve canine cases. CONCLUSIONS: Visceral leishmaniasis should be considered endemic in Brasilia based on the documented epidemiological behavior herein described and the confirmed autochthony of human cases.INTRODUÇÃO: A leishmaniose visceral é uma ameaça para a saúde pública no Brasil, considerando a elevada taxa de letalidade e a sua dispersão geográfica para grandes conglomerados urbanos durante os últimos 25 anos. Este trabalho teve como objetivo confirmar a suspeita de autoctonia de casos de leishmaniose visceral notificados de 2005 até 2009 em moradores de Brasília, Distrito Federal. MÉTODOS: Foi realizado em 2009 um estudo retrospectivo dos dados da vigilância obtidos na rotina e dos registros clínicos dos casos humanos notificados. RESULTADOS: Os dados dos inquéritos canino e entomológico revelaram a presença de Lutzomyia longipalpis e de cães com sorologia positiva para Leishmania na vizinhança onde ocorreram 19 dos 21 casos humanos desde 2005. A revisão das fichas de notificação e prontuários dos pacientes, em conjunto com os dados dos inquéritos canino e entomológico permitiram a comprovação da autoctonia de 21 casos humanos no Distrito Federal. A doença afetou predominantemente crianças (12/21), da região de Sobradinho (16/21), com quadro típico de febre, hepatoesplenomegalia e pancitopenia em 67% dos casos. Houve três óbitos no período. Houve sucesso no isolamento de Leishmania (Leishmania) chagasi de um caso humano e de doze casos caninos. CONCLUSÕES: A leishmaniose visceral deve ser considerada endêmica em Brasília, considerando o comportamento epidemiológico aqui descrito e a confirmação da autoctonia dos casos humanos.

Prion proteins are considered as the main agents for the Transmissible Spongiform Encephalopathies (TSE). The misfolded form, PrP Sc , which is also indicated as the etiological agent for TSE, exhibits high resistance to degradation in environmental processes. Soil contamination by prion proteins is a real environmental issue since contaminated soils can become potential reservoir and diffuser for TSE infectivity. In this work, the interaction of prion protein with organo- mineral complexes was studied by using a recombinant non pathogenic prion protein and a model soil system. This latter was represented by a soil manganese mineral coated with polymerized catechol. FT-IR spectra showed amide I and II sig- nals which revealed protein involvement in catechol polymers coating manganese oxide surface. CPMAS 13 C-NMR was applied to follow the complexation of the protein to the soil-like system. All the signals were attributed to C-N in peptidic bonds, alkyl chains and methyl groups. The NMR spectrum of the prion protein interacting directly with birnessite re- vealed disappearance of signals due to the paramagnetic nature of manganese oxide or protein abiotic degradation, while the presence of organic matter strongly reduced the disappearance of prion protein signals.

In this paper, the catalytic efficacy of peroxidase and manganese oxide, both commonly present in soil, to catalyze the formation of pyrogallol-phosphatase complexes was compared. The influence of several factors (e.g., the concentration of pyrogallol, the amount of catalysts, the nature of manganese oxide, birnessite, or pyrolusite, the incubation time, and the pH) on the transformation of pyrogallol and the characteristics and properties of the pyrogallol-phosphatase interaction products were investigated. The pyrogallol transformation mediated by both catalysts was very fast and increased by increasing the catalyst concentration. The nature of the catalyst also influenced the size and the molecular mass of the formed complexes. When polymerization of pyrogallol occurred with high intensity, a loss of phosphatase activity occurred, and it strongly depended on the pH at which the process was carried out and the catalyst. In particular, with peroxidase, the phosphatase activity was much lower in either suspensions or supernatants and not measurable in the insoluble complexes as compared to that measured in the presence of manganese oxides.

Purpose Persistent organic compounds exhibit declining extractability and bioavailability to microorganisms and other soil organisms with increasing contact time or ageing. Among the possible mechanisms are the association of organic compounds with natural organic matter. Ageing can reduce the negative effects that an organic pollutant may have on the biological, biochemical properties and phytotoxicity of the contaminated soil. The aim of the present work was to evaluate, under laboratory conditions, the response of an agricultural soil contaminated with phenanthrene (Phe) and subjected to 2-year ageing and the effects and potential remediation capabilities of compost and an effective Phe-degrading bacterial culture.Materials and methods A fresh agricultural soil was contaminated with Phe, supplemented with compost at two different rates and subjected to 2-year ageing under laboratory conditions. Phe was detected by HPLC analysis. The main biochemical and chemical properties of soil amended or not with compost were measured before and after the ageing process by using standard techniques. Germination tests were performed with Cucumis sativus L. and Lepidium sativum L. Results and discussion Significantly reduced amounts of Phe were extracted after 650 days and a greater amount of Phe accumulated in the soil humic fractions and preferentially in the humin–mineral fraction. A decrease of the extractable Phe from the 650-day aged samples occurred in the presence of the Phe-degrading bacterial culture but only after further 21–50 days of incubation. A similar decrease was measured also in the non-inoculated samples. The higher values of arylsulphatase and phosphatase measured after 650 days of incubation seem to indicate that the indigenous bacteria of the soil adapted to and survived the presence of the aged Phe, also because of its possible reduced toxicity. A little residual phytotoxicity was still measured indicating that the low amount of available Phe was high enough to reduce the germination of the two plant species. Conclusions The results support that complex phenomena occur in a soil when a contaminant is present and persist for long time in it. The higher amounts of Phe extracted by the humic fractions indicate that ageing of Phe actually occurred and was favoured by the presence of the high level of organic matter in the soil. Tested parameters showed different response to the presence of aged compound. Therefore, the choice of the biochemical parameter to use as indicator of soil quality might be crucial for obtaining correct and easily interpretable results.

ObjectivesThis study investigated the relationship between beta2-adrenergic receptor (B2AR) Ile164 polymorphism and coronary artery disease (CAD).BackgroundB2ARs are crucial to the regulation of vascular tone, and neoangiogenesis is impaired in the presence of isoleucine at position 164 (Ile164) B2AR gene polymorphism. No data deal with the role of the variants at position 164 of the B2AR gene in the setting of CAD.MethodsThe study population consisted of 330 patients undergoing percutaneous coronary intervention (PCI).ResultsThe Ile164 polymorphism frequency was higher in CAD (12.1% vs. 3%, p = 0.008) with respect to the control population. We divided our population into 2 groups: group 1 (290 patients, threonine/threonine genotype at position 164 [164Thr/Thr]) and group 2 (40 patients, threonine/isoleucine genotype at position 164 [164Thr/Ile]). Patients of group 2 presented an earlier onset of CAD (56.7 ± 7.8 vs. 59.5 ± 10, p = 0.04) and a higher incidence of multivessel disease (25.4% vs. 41%, p = 0.044). At follow-up, group 2 showed a higher incidence of new acute myocardial infarction (17.5% vs. 4.5%, p = 0.001), new PCI (37.5% vs. 13.1%, p < 0.0001), and cardiac death (10% vs. 3.1%, p = 0.036). Cox regression analysis identified Ile164 as an independent predictor of cardiac death (odds ratio [OR]: 3.731, 95% confidence interval [CI]: 1.004 to 13.867, p = 0.049) and an overall major adverse cardiac event (OR: 4.100, 95% CI: 1.945 to 8.640, p = 0.0001). A replication study was done on a population of 150 patients with peripheral artery disease. The presence of the Ile164 allele was associated with a higher incidence of acute myocardial infarction (54.5% vs. 25.2%, p = 0.035) or combined events (acute myocardial infarction, PCI, or coronary artery bypass graft) (63.6% vs. 30.9%, p = 0.027).ConclusionsOur study suggests that the B2AR Ile164 mutant is associated with a more aggressive CAD and adversely affects prognosis in patients undergoing PCI.

In the second half of the twentieth century, the indiscriminate release of xenobiotic chemicals of different chemical and structural complexity into the environment provoked serious and most often irreversible alterations of the natural environmental balance. Indeed, soil contamination by highly toxic compounds has greatly increased, with negative, irreversible effects on soil quality and health. Several chemical, biological, and biochemical soil properties have been profoundly altered, and their main effect has been the continuous loss of soil functions in sustaining the survival of living organisms. Among chemical pollutants, compounds like pesticides and polycyclic aromatic hydrocarbons arrive to the soil from different anthropic sources and have high toxicity toward humans, plants, and animals. Assessing the soil quality is a basic requirement for sustainable land use. Soil microbial and biochemical activities are sensitive to several natural and human-induced changes and may provide a helpful tool to...

Synthetic complexes were formed by interaction between acid phosphatase and either tannic acid or natural allophanic clay, and used as model systems to simulate enzymatic reactions occurring in heterogeneous environment. The presence of Mn and Mo on the kinetic constants of the immobilized phosphatase was also tested. Complexes were prepared at 30 °C by interaction of acid phosphatase and tannic acid or allophanic clay in the presence and absence of Mn or Mo. The effect of the addition order of the metal (micronutrient in soils) to the clay–enzyme complexes was evaluated, as well. Acid phosphatase immobilized on tannic acid and mineral clay showed variable activity levels. When phosphatase was immobilized on tannic acid, a recovery of about 51% of the initial enzymatic activity and a decrease of 17% of its catalytic efficiency was measured. The presence of Mn and Mo decreased the Vmax of phosphatase–tannic complexes as compared with that of the free phosphatase. All the added phosphatase molecules were immobilized onto the clay, when it was used as the immobilizing support. Phosphatase–clay complexes showed an increase of both enzymatic activity (higher Vmax value) and substrate affinity (lower Km values) as compared to the free enzyme, resulting in an increase by about 65% of the catalytic efficiency. The presence of Mn added at the same time with enzyme and clay decreased the enzymatic activity of the immobilized enzyme. However, when Mn was applied after the interaction of the enzyme with the clay, no significant effects on the residual activity of the immobilized enzyme were observed. Conversely, the order of the addition of Mo to the clay–enzyme complexes strongly influenced the activity and the kinetic behaviour of the immobilized enzyme. Moreover, Mo had higher inhibitory effects than Mn on phosphatase immobilized on both supports. The overall results seem to suggest that the immobilization of acid phosphatase on clay not only preserved but also enhanced the activity of the enzyme as compared with organic matter.

The aim of this work was to investigate the aerobic biodegradation of a composite under controlled composting conditions using standard test methods. Composite was formed by poly(lactic acid) (PLA), with and without the addition of maleic anhydride (MA), acting as coupling agent, thermoplastic starch (TPS) and short natural fibre (coir). For comparison its starting materials, such as TPS and matrix (containing 75 wt% of PLA and 25 wt% of TPS), were also tested. At the end of the incubation period, TPS appeared to be the most bio-susceptible material being totally biodegraded and the matrix showed a higher level of biodegradation (higher amounts of evolved CO2) than PLA, probably due to the TPS domains preferentially attacked by microorganisms and increasing the percentage of carbon dioxide produced. Fibres seemed to play a secondary role in the process as confirmed by the slight differences in carbon dioxide produced. The compatibilised composite revealed a lower percentage of evolved CO2 than the uncompatibilised one. Finally, the degradation results were confirmed by thermal properties' changes of tested materials at different incubation times, as monitored by thermal analysis, and by the scanning electron microscopy (SEM) analyses of the compost aged samples. SEM micrographs showed the formation of patterns and cracks on the surface of the materials aged in the compost evidencing a profound loss of structure. Moreover, an extended biofilm (evident also with optical microscopy observation) was detected on the biodegraded materials, thus indicating the growth of a large number of bacteria and fungi on their surfaces.

Pentachlorophenol (PCP) is a toxic compound which is widely used as a wood preservative product and general biocide. It is persistent in the environment and has been classified as a persistent organic pollutant to be reclaimed in many countries. Fungal bioremediation is an emerging approach to rehabilitating areas fouled by recalcitrant xenobiotics. In the present study, we isolated two fungal strains from an artificially PCP-contaminated soil during a long-term bioremediation study and evaluated their potential as bioremediation agents in depletion and detoxification of PCP in soil microcosms. The two fungal strains were identified as: Byssochlamys nivea (Westling, 1909) and Scopulariopsis brumptii (Salvanet-Duval, 1935). PCP removal and toxicity were examined during 28 days of incubation. Bioaugmented microcosms revealed a 60% and 62% PCP removal by B. nivea and S. brumptii, respectively. Co-inoculation of B. nivea and S. brumptii showed a synergetic effect on PCP removal resulting in 95% and 80% PCP decrease when initial concentrations were 12.5 and 25 mg kg-1, respectively. Detoxification in bioaugmented soil and the efficient role of fungi in the rehabilitation of PCP contaminated soil were experimentally proven by toxicity assays. A decrease in inhibition of bioluminescence of Escherichia coli HB101 pUCD607 and an increase of germination index of mustard (Brassica alba) seeds were observed in the decontaminated soils.

Polycyclic aromatic hydrocarbons (PAHs) are highly recalcitrant widespread environmental pollutants. Bioremediation, accomplished by the introduction of PAH-degrading microorganisms (bioaugmentation) and/or by applying additional nutrients (biostimulation) into a contaminated system is a valuable alternative to traditional chemical and physical treatments for the decontamination of PAH-contaminated soils. We investigated on a laboratory scale the fate of phenanthrene (Phe), selected to represent PAHs, when added to a fresh, agricultural soil with no history of PAH contamination. The relative effect of compost (C), applied at two different doses (C1=0.27%, and C2=0.83%, corresponding to 10 and 30 t ha−1, respectively), and the efficiency of a Phe-degrading bacterial culture inoculated into the soil (S) and soil–compost (S–C1 and S–C2) systems were investigated. Changes in various functionally related properties such as microbial biomass, basal respiration, and soil hydrolases and oxido-reductases activities were measured over time. The variations of the main physical and chemical properties were also monitored. The soil showed an intrinsic capability for degrading Phe, and this was enhanced and stimulated by the lower compost dose (a decrease of the extractable Phe from 70% to about 50% of that initially added, and higher kinetic Phe disappearance constants). A simultaneous, rapid increase of soil respiration and microbial biomass, and higher phosphatase and arylsulphatase activities were measured, suggesting that microbial growth and activity had increased. The inoculation with Phe-degrading bacterial cells strongly accelerated the Phe degradation. After 15 d of incubation, the residual Phe decreased to 10% in S and S–C1 and to zero in S–C2, respectively. No apparent effects were observed for the higher compost dose. Several of the soil properties showed differentiated responses to the presence of the Phe, the compost and/or the exogenous culture. As a general response, soil systems with and without the inoculated cells showed similar trends for several of the measured enzymatic properties (e.g. phosphatase, arylsulphatase, β-glucosidase and urease activities), indicating that the intrinsic soil enzymatic activity was not affected by the exogenous microorganisms. Temporary and permanent changes were observed for several of the properties investigated, thereby providing useful information on the impact of Phe on soil metabolic activity.

The activity and catalytic properties of two preparations of acid phosphatases from potato and sweet potato in the presence of different levels of manganese (Mn) and molybdenum (Mo) were determined...

Prion proteins are regarded as the main agents of transmissible spongiform encephalopathies. Understanding their fate in soil may be crucial to elucidate the dissemination of the prion in the environment, associated with a possible transmission of infectivity. Studies were performed with simplified model systems, derived by the birnessite-mediated oxidative polymerization of catechol, which simulate processes naturally occurring in soil. A benign full-length recombinant purified ovine protein (PrP) (residues 23–234), as well as a truncated-form ovPrP (tPrP) (103–234) were utilized. Catechol and prion protein interacted under experimental conditions that reproduced the interaction of PrP with soluble organic matter or with insoluble organic matter during or after formation of catechol polymers. PrP stability in all buffers and chemicals was preliminarily monitored by circular dicroism (CD) measurements. The disappearance of protein molecules from the solution, the decrease of UV–Visible absorbance of supernatants, and the FT-IR spectra and the elemental analyses of solid-phase residues indicated that both PrP and tPrP were involved in catechol polymerization by birnessite. Furthermore, a clear flocculation of soluble catechol–protein polymeric products in solid aggregates was observed when PrP was added to the supernatants. Different kinds of extracting agents were not able to desorb/extract PrP as well as tPrP from the formed solid aggregates, thereby highlighting the high stability of protein–organic and –organo-mineral complexes.

Pentachlorophenol (PCP) has been used worldwide as a wood treatment agent and biocide. Its toxicity and extensive use have placed it among the most hazardous environmental pollutants. The response of a PCP-contaminated agricultural soil to the addition of solid urban waste compost and two exogenous Ascomycota fungal strains Byssochlamys nivea and Scopulariopsis brumptii was evaluated. The experiments were conducted in soil microcosms incubated for 28 days at 25 °C and 60 % moisture content. The depletion of PCP and the changes in biochemical soil properties (i.e. microbial biomass, soil respiration, dehydrogenase and fluorescein diacetate hydrolysis activities) were detected. The addition of PCP severely depressed some of the tested biochemical properties such as microbial biomass, dehydrogenase and fluorescein diacetate hydrolysis activities. By contrast, compost limited the negative effect of PCP on the dehydrogenase activity and soil respiration. When compost and fungal strains were contemporary present, a synergistic effect was observed with a reduction of more than 95 % of the extractable PCP after 28 days of incubation. No differences in PCP depletion resulted when fungi or compost were individually used. Our results indicate that many processes (i.e. microbial degradation and sorption to organic matter) likely occurred when PCP was added to the soil. The compost and the fungal strains, B. nivea and S. brumptii, showed good capability to tolerate and degrade PCP so that they could be successfully used in synergistic effect to treat PCP polluted soils.

Three numerical indexes, based on soil enzyme activities, which can discriminate between altered and unaltered soils, are presented and validated. Seven enzymes were measured at three different agricultural sites subjected to contamination by municipal and industrial wastes (site 1), intensive cultivation without either crop rotation or organic fertilization (site 2), and irrigation with brackish water (site 3). At each site neighbouring, unaltered soils were sampled and analysed as control soils. The three indexes were developed by means of canonical discriminant analysis (CDA) using data from two sites, while the third site was kept aside as an independent test. The first index is built up using all of the enzyme activities studied; the second, using the most discriminating enzyme activities only; and the third was developed for testing against data in published papers that deal with enzyme measurements in soils under different management regimes. The three indexes were able to discriminate between altered and control soils when applied to the data set from the third site, i.e., that not used for index development. When tested against published data, the third index was usually able to discriminate altered soils from controls by higher index scores. This index was successful in most cases: it was consistently able to classify soils according to their reported degree of alteration. Our results confirm that enzyme activities are suitable indicators of soil alteration and may be usefully integrated to develop soil alteration indexes suitable for monitoring soil status under different conditions.

The use of microorganisms (bioremediation) and plants (phytoremediation) to remediate polluted environments is a promising and growing area of environmental biotechnology. The first productive step in cell-transformation of xenobiotic substances, including recalcitrant and even plastic materials, is usually catalyzed by ecto and extra cellular enzymes, released by the cells in their nearby environment. Extra cellular enzymes include a large range of oxidoreductases and hydrolases. Both these enzymes may explicate a degradative function and transform polymeric substances into partially degraded or oxidized products that can be easily up-taken by cells. The presence of the whole cell and its metabolic pathways to be completed are required. The use of extra cellular and/or cell-free enzymes has been also proposed as an innovative remediation technique. They can offer some advantages over the use of microbial cells. Several bottlenecks, however, still restrict their practical application in the recovery of polluted environments. A brief survey of many aspects dealing with the characteristics and potential abilities of both cell-present- and cell-free extra cellular enzymes is provided. The feasibility of their application for bioremediation of polluted soils has been briefly addressed, as well.

The transformation by an oxidoreductase (a laccase from Rhus vernificera) of a mixture of four phenols (catechol, methylcatechol, m-tyrosol and hydroxytyrosol) that simulates a typical wastewater derived from an olive oil factory was investigated. Results achieved in this study confirm that laccase-mediated transformation of phenols depends on the nature and the initial concentration of the involved phenol, the time course of the reaction, and mainly, on the complexity of the phenolic incubation mixture. Actually, the four phenols each have a completely different response to enzyme action both in terms of quantitative and kinetic transformation. For example, after 24-h incubation, methylcatechol was completely removed, whereas 30% of untransformed hydroxytyrosol and catechol and more than 65% of m-tyrosol were still present in the reaction mixture. A reduction of enzyme activity occurred for all phenols after enzymatic oxidation. No correspondence between phenol transformation and disappearance of enzymatic activity was observed, thus suggesting that different mechanisms are probably involved in the laccase-mediated transformation of the four phenols. The behavior of phenols became more complex when an increasing number of phenols was present in the reaction mixture, and even more so when different concentrations of phenols were used. Competitive effects may arise when more than one phenol is present in the reaction solution and interacts with the enzyme.