Bio-transformation of poultry litter and activated sewage sludge to produce biomixtures for the remediation of water polluted with pesticides.

The aim of this study was to formulate novel biomixtures with the ability to dissipate globally used pesticides. For this, an effective stabilization of two wastes, poultry litter and activated sewage sludge, was achieved through a combination of composting and vermicomposting, with the aid of the earthworm Eisenia fetida. Hence, two different mixtures were prepared combining the wastes with and without the addition of sewage sludge, and their physicochemical and microbiological characterization was examined during both processes.

Vermistabilization of excess sludge employing Eisenia fetida: Earthworm histopathological alterations and phytotoxicity evaluation.

The aim of this work was to stabilize excess sludge (ES) coming from a wastewater treatment plant (WWTP) by vermistabilization and to evaluate ecotoxicological effects over the earthworm species Eisenia fetida. Three mixtures were made up in triplicate using different volume ratios of ES and soil (S) (100% ES, 70:30% ES:S and 30:70% ES:S in wet weight basis). Earthworms were added in order to compare vermicomposting vs.

Bioremediation of hydrocarbon contaminated soil using local organic materials and earthworms.

Bioremediation technologies have demonstrated significant success on biological quality recovery of hydrocarbon contaminated soils, employing techniques among which composting and vermiremediation stand out. The aim of this study was to evaluate the efficiency of these processes to remediate diesel-contaminated soil, employing local organic materials and earthworms. During the initial composting stage (75 days), the substrate was made up using contaminated soil, lombricompost, rice hulls and wheat stubbles (60:20:15:5% w/w).

Biodegradation of pesticide-contaminated wastewaters from a formulation plant employing a pilot scale biobed.

In this work, a pilot biobed was built up to treat pesticide-contaminated wastewaters discharged from a formulation plant. The pre-treated wastewater was spiked with additional pesticides in order to simulate a scenario of higher contamination: glyphosate, atrazine, imidacloprid, prometryn and carbendazim were added to reach a final Total Organic Carbon (TOC) concentration of 70 mg L. An Intermediate Bulk Container (IBC) was filled with a biomixture of soil and foxtail millet stubble (50:50% v v), and 200 l of the wastewater was added to the system recycling tank.

Poultry litter stabilization by two-stage composting-vermicomposting process: Environmental, energetic and economic performance.

Poultry litter (PL) is a heterogeneous mixture that contains bedding materials, antibiotics, dead skin, feed scraps, water, feathers and the resulting microbiota from poultry production cycle. Although its treatment does not receive attention, it is an important organic resource generated in the north-east region of Santa Fe Province since animal primary production is one of the main economic activities there and in the whole country. The objective of this work was to analyse the economic and energy aspects and the environmental impact of two scenarios corresponding to treat two different mixtures of organic wastes: Eucalyptus sp.

Earthworms to improve glyphosate degradation in biobeds.

In this work, earthworm effect on the efficiency of biobeds for glyphosate degradation was studied. Three biomixtures with and without the addition of earthworms (Eisenia fetida species) were evaluated. The initial concentration of glyphosate was 1000 mg/kg biomixture.

Glyphosate and aminomethylphosphonic acid degradation in biomixtures based on alfalfa straw, wheat stubble and river waste.

The aim of the work was to evaluate novel biomixtures for their use on biopurification systems (BPS) in Argentina also called biobeds. Glyphosate and aminomethylphosphonic acid (AMPA) degradation was evaluated on biomixtures containing local materials: alfalfa straw (As), wheat stubble (Ws), river waste (Rw) and soil. Glyphosate, AMPA concentrations and biological activity were followed with time.

Microparticles based on ionic and organosolv lignins for the controlled release of atrazine.

Lignins are natural polymers of the lignocellulosic biomass. Nowadays, there is a growing interest in developing value-added products based on lignins due to their renewability, low cost and abundance. In this work, lignin microspheres from organosolv and ionic isolation processes were prepared for the controlled release of atrazine.

Earthworms to assess the innocuousness of spent biomixtures employed for glyphosate degradation.

In this study, the innocuousness of different biomixtures employed for glyphosate degradation was tested through Eisenia fetida earthworms. Eight biomixtures were prepared with local materials: alfalfa straw (AS), wheat stubble (WS), river waste (RW) and two different soils (A and B). Each biomixture was divided into two equal portions: one without glyphosate application (control substrate) and the other was sprayed with a commercial glyphosate formulation of 1,000 mg glyphosate a.

Advanced oxidation of commercial herbicides mixture: experimental design and phytotoxicity evaluation.

In this work, the suitability of the UV/HO process for commercial herbicides mixture degradation was studied. Glyphosate, the herbicide most widely used in the world, was mixed with other herbicides that have residual activity as 2,4-D and atrazine. Modeling of the process response related to specific operating conditions like initial pH and initial HO to total organic carbon molar ratio was assessed by the response surface methodology (RSM).

Arsenic sorption onto titanium dioxide, granular ferric hydroxide and activated alumina: batch and dynamic studies.

The aim of this work was to evaluate and compare the efficiencies of three different adsorbents for arsenic (As) removal from water: titanium dioxide (TiO2), granular ferric hydroxide (GFH) and activated alumina (AA). Equilibrium experiments for dissolved arsenite and arsenate were carried out through batch tests. Freundlich and Langmuir isotherm models were adopted and their parameters were estimated by non-linear regressions.

Modeling of degradation kinetic and toxicity evaluation of herbicides mixtures in water using the UV/H2O2 process.

The UV/H2O2 process was applied to the treatment of different mixtures of herbicides in water. Glyphosate, the herbicide most used in the world, was mixed with other hormonal herbicides with residual activity as 2,4-D and dicamba. The main goals of the study were to develop a kinetic model for interpreting the simultaneous oxidation of two mixtures (glyphosate plus 2,4-D and glyphosate plus dicamba).

Simplified reaction kinetics, models and experiments for glyphosate degradation in water by the UV/H2O2 process.

A simplified mathematical model to describe the oxidative degradation of glyphosate employing hydrogen peroxide and UV radiation was developed based on a sequence of predominant reactions. The kinetics obtained include all the required significant variables. Consequently, not only were concentration dependencies examined but also the influence of a detailed spatial description of the radiation field was included as part of the modeling.

Arsenic removal from water employing a combined system: photooxidation and adsorption.

A combined system employing photochemical oxidation (UV/H2O2) and adsorption for arsenic removal from water was designed and evaluated. In this work, a bench-scale photochemical annular reactor was developed being connected alternately to a pair of adsorption columns filled with titanium dioxide (TiO2) and granular ferric hydroxide (GFH). The experiences were performed by varying the relation of As concentration (As (III)/As (V) weight ratio) at constant hydrogen peroxide concentration and incident radiation.

Photodegradation of chlorpyrifos in water by UV/H2O2 treatment: toxicity evaluation.

Chlorpyrifos (CP) is an organophosphorus pesticide widely used in agriculture. Due to its toxicity, it has been necessary to develop a treatment to eliminate the environmental wastes generated by this substance. The combination of UV radiation and hydrogen peroxide seemed an interesting option to reduce the concentration of CP in water, as it has proved to be a simple and effective method to degrade other similar pesticides.

Effectiveness evaluation of glyphosate oxidation employing the H(2)O(2)/UVC process: toxicity assays with Vibrio fischeri and Rhinella arenarum tadpoles.

The H(2)O(2)/UVC process was applied to the photodegradation of a commercial formulation of glyphosate in water. Two organisms (Vibrio fischeri bacteria and Rhinella arenarum tadpoles) were used to investigate the toxicity of glyphosate in samples M(1,) M(2), and M(3) following different photodegradation reaction times (120, 240 and 360 min, respectively) that had differing amounts of residual H(2)O(2). Subsamples of M(1), M(2), and M(3) were then used to create samples M(1,E), M(2,E) and M(3,E) in which the H(2)O(2) had been removed.

Arsenic (III) oxidation of water applying a combination of hydrogen peroxide and UVC radiation.

Arsenic is toxic to both plants and animals and inorganic arsenicals are proven carcinogens in humans. The oxidation of As(III) to As(v) is desirable for enhancing the immobilization of arsenic and is required for most arsenic removal technologies. The main objective of this research is to apply an Advanced Oxidation Process that combines ultraviolet radiation and hydrogen peroxide (UVC/H(2)O(2)) for oxidizing aqueous solutions of As(III).

Composition and volatile profiles of commercial Argentinean blue cheeses.

Background: A first approach was made to acquire knowledge of the global composition, proteolysis, lipolysis and volatile profile of Argentinean blue cheeses. A total of 20 samples belonging to six leading commercial brands were analysed. A comparison of the results with bibliographical data on other blue cheeses was performed and the variability among and within dairy plants was also evaluated.

Influence of milk pretreatment on production of free fatty acids and volatile compounds in hard cheeses: heat treatment and mechanical agitation.

This work aimed to identify technological steps that can increase fat hydrolysis and volatile compounds production in hard cheeses; these biochemical events have been related with improved piquant taste and development of genuine flavor during cheese ripening. For that purpose, 2 different pretreatments of cheese milk were tested: heat treatment and mechanical agitation. Both factors were assayed at 2 levels: milk was either batch pasteurized or nonthermally treated, and mechanical agitation was either applied or not applied.

Glyphosate degradation in water employing the H2O2/UVC process.

Glyphosate is the organophosphate herbicide most widely used in the world. Any form of spill or discharge, even if unintentional, can be transferred to the water due to its high solubility. The combination of hydrogen peroxide and UV radiation could be a suitable option to decrease glyphosate concentration to acceptable limits.

Degradation of a mixture of pollutants in water using the UV/H2O2 process.

The degradation reaction of a simple mixture of pollutants (dichloroacetic acid + formic acid) employing H2O2 and UVC radiation (253.7 nm) has been studied in a well-mixed reactor which operates inside a recycling system. The aim of this work is to develop a systematic methodology for treating degradation of mixtures of pollutants, starting from a rather manageable system to more complex aggregates.

Characterisation of proteolysis profile of Argentinean sheep cheeses made by two different production methods.

Background: In this work the proteolysis profiles of Argentinean sheep cheeses made by two different production methods were studied in order to develop products with typical and defined features. Cheeses with a starter of Streptococcus thermophilus, curd cut to corn grain size, washed and heated to 43 degrees C (S cheeses) and cheeses with a mixed starter of Streptococcus thermophilus, Lactobacillus helveticus and Lactobacillus bulgaricus, curd cut to rice grain size, unwashed and heated to 47 degrees C (L cheeses) were manufactured. The cheeses were ripened at 12 degrees C and 80% relative humidity for 180 days and samples were taken throughout this period.

Pategrás cheese as a suitable carrier for six probiotic cultures.

The viability of five single-strain and one three-strain probiotic cultures was assessed during Pategrás cheese ripening. Probiotics were inoculated into cheese-milk after a pre-incubation step - intended to improve their survival - or directly as a lyophilised culture; control cheeses without probiotics were also obtained. pH of probiotic and control cheeses was similar, except in probiotic cheeses containing the strain Lb.

Production of flavour compounds from fat during cheese ripening by action of lipases and esterases.

The milk fat is an essential component for the development of correct flavour in cheese. The lipolysis and catabolism of fatty acids are two biochemical events very important on flavour development of some cheese varieties. The role and characteristics of various lipolytic agents during cheese ripening is reviewed and discussed.