15 research outputs found
Assessment of different spent mushroom substrates to bioremediate soils contaminated with petroleum hydrocarbons
Bioremediation techniques are being developed as substitutes for physical–chemical methodologies that are expensive and not sustainable. For example, using the agricultural waste spent mushroom substrate (SMS) which contains valuable microbiota for soil bioremediation. In this work, SMSs of four cultivated fungal species, Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, and Agaricus bisporus were evaluated for the bioremediation of soils contaminated by petroleum hydrocarbons (TPHs). The bioremediation test was carried out by mixing the four different SMSs with the TPH-contaminated soil in comparison with an unamended soil control to assess its natural attenuation. To determine the most efficient bioremediation strategy, hydrolase, dehydrogenase, and ligninolytic activities, ergosterol content, and percentage of TPHs degradation (total and by chains) were determined at the end of the assay at 40 days. The application of SMS significantly improved the degradation of TPHs with respect to the control. The most effective spent mushroom substrate to degrade TPHs was A. bisporus, followed by L. edodes and P. ostreatus. Similar results were obtained for the removal of aliphatic and aromatic hydrocarbons. The results showed the effectiveness of SMS to remove aliphatic and aromatic hydrocarbons from C10 to C35. This work demonstrates an alternative to valorizing an abundant agricultural waste as SMS to bioremediate contaminated soil
Design of a hydroponic test to evaluate the biostimulant potential of new organic and organomineral products
Currently, the use of biostimulants is increasing due to the need for greater productivity in agriculture. The
European Union presented a new fertilizer regulation, UE 2019/1009, appearing for the first time the concept of
biostimulants. Its main objective is to improve the efficiency of plants in the absorption and assimilation of
nutrients or their tolerance to biotic or abiotic stresses, regardless of the nutrient content of the product. The
objective of this work consisted in the development of a methodology to test in a short-term experiment the
efficiency of commercial products as potential biostimulants in a crop of Capsicum annuum L. in strictly hydroponic conditions. Plants were irrigated with the respective product at the recommended dose in water,
without the addition of other nutritional sources for 15 days. At the end of the test, the weights of the root and
aerial part, the humidity, the chlorophyll indexes, and nutritional leaf content, as well as the volume and
morphology of the roots and plants were obtained to evaluate the biostimulant effects on the plant growth and
development. The water consumption was also evaluated to analyze whether any of the products generates
greater water savings. The study concluded that the nutritive solutions with biostimulants produced a greater
increase in the weight of the plant and a lower percentage of leaf moisture, as well as higher values of leaf
chlorophyll. On the other hand, it was humic, fulvic, and algae biostimulants that presented the best values in
terms of water savings. The methodology developed could be set to test in the short term the biostimulant potential of new productsThis research did not receive any specific grant from funding
agencies in the public, commercial, or not-for-profit sector
An assessment of Pleurotus ostreatus to remove sulfonamides, and its role as a biofilter based on its own spent mushroom substrate
A double strategy based on the removal of sulfonamide antibiotics by Pleurotus ostreatus and adsorption on spent mushroom substrate was assessed to reclaim contaminated wastewater. P. ostreatus was firstly tested in a liquid medium fortified with five sulfonamides: sulfamethoxazole, sulfadiazine, sulfathiazole, sulfapyridine and sulfamethazine, to evaluate its capacity to remove them and to test for any adverse effects on fungal growth and for any reduction in residual antibiotic activity. P. ostreatus was effective in removing sulfonamides up to 83 to 91% of the applied doses over 14 days. The antibiotic activity of the sulfonamide residues was reduced by 50%. Sulfamethoxazole transformation products by laccase were identified, and the degradation pathway was proposed. In addition, P. ostreatus growth on a semi-solid medium of spent mushroom substrate and malt extract agar was used to develop a biofilter for the removal of sulfonamides from real wastewater. The biofilter was able to remove more than 90% of the sulfonamide concentrations over 24 h by combining adsorption and biodegradation mechanisms.This work was supported by the Ministry of Science and Innovation of Spain (Project AGL2016-78490-R
Enhancement of methane production from livestock manure with pre-treatments based in fungi of genus Pleurotus
Livestock manure, traditionally used just as fertilizer, can be energetically valued to produce biogas as an
attractive alternative, since nowadays, energy production and its cost stands for a pressing problem around the
world. Nevertheless, the presence of lignin in manure hinders the production of methane. This could be improved
by pre-treating the manure with ligninolytic fungi, able to break lignin and therefore facilitate the hydrolysis step
for the hydrolytic bacteria, yielding higher volumes of biomethane. Three strategies of incubation with living
fungi of genus Pleurotus were evaluated to enhance methane production from livestock manure mixed with
bedding material: short term (two weeks 2L container) and long term (two months 400 L container) and 24 h (2 L
container) with a crude water extraction of Pleurotus extracellular enzymes. The positive effect of the fungal
treatment was observed in the three strategies obtaining an increase in methane production with respect to the
control manure of 7% at short term, 111% at long term and 173% (crude enzymatic extract). Consequently, the
strategy of using crude enzyme extracts from Pleurotus to improve hydrolysis step as pre-treatment of manure
should be considered as a novel, easy, cheap and promising tool to optimize methane productionThis research was funded by a contract with the company Kepler
Ingeniería y Ecogestión SL managed by Foundation from University
Autónoma of Madrid (FUAM) and with reference 01091
Synergistic effects of biochar and biostimulants on nutrient and toxic element uptake by pepper in contaminated soils
BACKGROUND: Nowadays a significant amount of land contaminated with toxic elements is being used for agriculture, posing a serious risk of crop contamination and toxicity. Several methodologies are being used to remediate soil contamination, including the use of amendments such as biochar. This work evaluated the effects of biochar combined with different fertirrigations (water, a conventional fertilizer solution, or a fertilizer solution with a commercial biostimulant derived from leonardite) on the availability of toxic elements and nutrients for pepper cultivated in a soil contaminated with As, Cd, Pb, and Zn. RESULTS: Irrigation with fertilizer solutions improved plant growth regardless of the biochar amendment. Biochar decreased the bioavailability of Cu and Pb in soil and the Cu content in pepper leaves. Combined with fertilization, biochar also decreased plant As and Pb content. Biochar combined with biostimulant decreased the bioavailable content of Cd in soil and its uptake by pepper plants. CONCLUSION: The use of biochar and biostimulant presented advantages for plant production in a non-suitable scenario of nutrient scarcity and contaminationWe thank the agronomic technicians Manuel Campos Macossay
and Carlos Rodriguez Orta for the location of the soil and supply
of materials. This article is the result of a research project ‘Compar ison of agronomic efficiency between Huma Gro® products and
mineral conventional fertilizers’ funded by Bio Huma Netics Inc.
(Gilbert, Arizona, USA). Bio Huma Netics Inc. did not participate
in the experimental procedures or in the evaluation of the result
Comparative study of the chemical composition and antifungal activity of commercial brown seaweed extracts
IntroductionA sustainable agriculture and the great increase in consumers of organic products in the last years make the use of natural products one of the main challenges of modern agriculture. This is the reason that the use of products based on seaweed extracts has increased exponentially, specifically brown seaweeds, including Ascophyllum nodosum and Ecklonia maxima.MethodsIn this study, the chemical composition of 20 commercial seaweed extract products used as biostimulants and their antifungal activity against two common postharvest pathogens (Botrytis cinerea and Penicillium digitatum) from fruits were evaluated. Data were processed using chemometric techniques based on linear and non-linear models.Results and discussionThe results showed that the algae species and the percentage of seaweed had a significant effect on the final composition of the products. In addition, great disparity was observed between formulations with similar labeling and antifungal effect of most of the analyzed products against some of the tested pathogens. These findings indicate the need for further research
Prospective individual patient data meta-analysis of two randomized trials on convalescent plasma for COVID-19 outpatients
Data on convalescent plasma (CP) treatment in COVID-19 outpatients are scarce. We aimed to assess whether CP administered during the first week of symptoms reduced the disease progression or risk of hospitalization of outpatients. Two multicenter, double-blind randomized trials (NCT04621123, NCT04589949) were merged with data pooling starting when = 50 years and symptomatic for <= 7days were included. The intervention consisted of 200-300mL of CP with a predefined minimum level of antibodies. Primary endpoints were a 5-point disease severity scale and a composite of hospitalization or death by 28 days. Amongst the 797 patients included, 390 received CP and 392 placebo; they had a median age of 58 years, 1 comorbidity, 5 days symptoms and 93% had negative IgG antibody-test. Seventy-four patients were hospitalized, 6 required mechanical ventilation and 3 died. The odds ratio (OR) of CP for improved disease severity scale was 0.936 (credible interval (CI) 0.667-1.311); OR for hospitalization or death was 0.919 (CI 0.592-1.416). CP effect on hospital admission or death was largest in patients with <= 5 days of symptoms (OR 0.658, 95%CI 0.394-1.085). CP did not decrease the time to full symptom resolution
AICLE - CLIL - EMILE : educació plurilingüe. Experiencias, research & polítiques
Aquest volum és resultat del projecte R+D+i EDU2010-15783 Discurso Académico en lengua extranjera: Aprendizaje y evaluación de contenidos científicos en el aula multilingüe, finançat pel MICINN.El present volum és el resultat de la selecció de les millors comunicacions presentades en la primera Taula Rodona Internacional TRI-CLIL sobre Aprenentatge Integrat de Continguts i Llengües (AICLE). El congrés va aconseguir reunir professionals de la docència i de la recerca, tant de matèries escolars, llengües estrangeres i llengües considerades oficials o co-oficials a diferents territoris, que esdevenen llengües addicionals per a la població escolar migrada
Evaluation of Commercial Humic Substances and Other Organic Amendments for the Immobilization of Copper Through 13C CPMAS NMR, FT-IR, and DSC Analyses
The application of organic amendments to contaminated agricultural lands can immobilize metals and improve soil conditions. The chemical structures and long-term stability of commercial humic substances and other composted organic amendments (sheep and horse manure, vermicompost, pine bark, and pruning waste) were analyzed using 13C CPMAS NMR, FT-IR, and DSC to evaluate their use in soil remediation. The interactions of humic substances and manure with Cu (0 and 5000 mg kg−1) at different pH (2.5 and 5.0) were studied through a batch adsorption experiment observing the changes in their molecular structure using spectroscopic techniques. Humic substances exhibited high aromaticity and phenolic and carboxylic group content, with great affinity for Cu complexation. Humic substances and pruning waste were the most stable due to their high recalcitrant organic matter contents, whereas manure was the least stable, given the labile nature of its organic matter content. There were considerable changes in the carboxylic and phenolic groups of humic substances with pH, and also with Cu, albeit in a lesser extent, especially at pH 5.0, suggesting the great sorption capacity of humic substances and the key role of pH and these functional groups in metal complexation. Manure did not exhibit such changes. Commercial humic substances could be useful amendments for the remediation of contaminated agricultural soils due to their high sorption capacities and long-term stability