Agro-industrial Residues Research Articles

ANTIMICROBIAL PIGMENT FROM FUSARIUM GRAMINEARUM: OPTIMIZING CONDITIONS AND UTILIZING AGRO-INDUSTRIAL RESIDUES

Fusarium sp. produces various bioactive pigments widely used in pharmaceuticals, cosmetics, and the food industry. This study investigated the antimicrobial effect of the pigment produced from the highest pigment-producing Fusarium sp. strain and determined the optimum growth conditions and agro-industrial residues to obtain maximum pigment production. Fusarium equiseti, Fusarium graminearum, and Fusarium poae strains were tested in terms of their pigment production levels. Pigment quantification was assessed by a UV–Visible Spectrophotometer at 500 nm. Antimicrobial tests were determined by Disc Diffusion and Well Diffusion Methods. According to our results, the highest amount of pigment-producing strain was F. graminearum (p<0.001) and malt extract broth (MEB) was the optimum growth media (p<0.001). Extracted F. graminearum pigment was antimicrobial against B. cereus and S. aureus with a zone of inhibition diameters of 10.2 and 14.9 mm respectively. Initial pH levels of 8, 150 rpm rotation speed, 30 ºC temperature, and 9 days of incubation under the light condition in MEB media were determined as the optimum growth conditions for the highest reddish pigment production. Moreover, 10-2 times diluted molasses, Turkish feta cheese whey, and Turkish cheddar cheese whey were found as suitable low-cost growth media for reddish pigment production by F. graminearum. Our findings not only represent a pigment that might be used in the food industry as an antimicrobial bio-colorant but also show the potential use of molasses and whey as low-cost growth media for reddish pigment production by F. graminearum.

Fungicide Effect of a Novelty Antimicrobial Biosurfactant Extract Alone or Combined with Copper Oxychloride on Botrytis cinerea Cells

Microbial contaminations represent an important issue for crop production, resulting in tons of losses worldwide every year. One of the highest-risk pathogens involved in these infections is Botrytis cinerea, which is responsible for the grey mold disease. In this study, a biosurfactant extracted from corn steep liquor (CSL), an agro-industrial residue from the corn-milling industry, was used in combination with copper oxychloride (Cu-Oxy), a copper-based pesticide, to evaluate their fungitoxic activity on B. cinerea cells. The results showed that the mixture of 2 g/L of Cu-Oxy with 16 g/L of the biosurfactant extract from CSL, named biosurfactant pesticide formulation (BS-P), helped in the reduction of colony growth, in the decrease of biomass production, and in the improvement of copper bioaccumulation on fungal mycelium in comparison with aqueous solutions of commercial and pure-copper-based fungicides. A factorial design was conducted to obtain the best operational conditions for enhancing the bioaccumulation of copper by B. cinerea cells in the presence of BS-P, resulting in a maximum copper uptake of 2122 µg Cu/g dry weight when using 1 g/L of Cu-Oxy combined with 8 g/L of CSL biosurfactant extract at an incubation temperature of 15 °C. It was also proved that, due to the absence of the biosurfactant extract, the amount of copper bio-adsorbed by fungal mycelium was considerably decreased and, therefore, so was its fungitoxic activity. These results suggest that the biosurfactant extract studied could be involved in eco-friendlier pesticide formulations, reducing the environmental impact of copper-based active principles.

Use of Agroindustrial Materials as Activated Carbon Precursors for Caffeine Removal: Global Overview

Objective: Prepare a global overview of agro-industrial residues used for activated carbon (CA) production, seeking caffeine removal of water bodies. Theoretical reference: Aiming the adequate understand of involved processes, as well as each stage when adsorption occurred. The theoretical concepts might help to analyse how important is pollution of emerging contaminants in water bodies, as a current environmental problem. Method: A data survey was developed in general perspective, using information from literature published in online repositories, such as Scopus and Science Direct, trough investigations that seek the use of agro-industrial residues for production of activated carbons and, also, their caffeine removal parameters analysis. Results and conclusion: The analysis results of the different methodologies applied in studies for activated carbon production from agro-industrial residues, showed that good caffeine adsorption process and the adequate characteristics of each adsorbent material, depend on processes and conditions adopted by each researcher. In this way, the different studies here analysed showed the importance of using industry waste, helping to reduce waste volumes in landfills and, at the same time, the search for new technologies that could help to remove emerging contaminants, such as caffeine. Originality/value: This study provides different basic and methodological concepts related to carbonization processes from agro-industrial waste, verified and studied by different authors for caffeine elimination; and also the importance of tracking new economical and environmentally friendly precursor materials.

Immobilization of Cr3+, Cd2+, and Pb2+ added to calcareous soil amended with composted agro-industrial residues

The bioavailability of trace metals in soils poses a major threat to the environment, especially with massive mineral fertilizers added to increase plant yield. A plot experiment was conducted for the effectiveness evaluation of compost and vermicompost, recycled from agro-industrial wastes, in immobilizing chromium, cadmium, and lead added to calcareous soil (artificially contaminated). Moreover, immobilization efficiency was compared to the natural occurrence of these metals in the soil without metal addition (uncontaminated soil). In both soils, amendments and mineral fertilizers were applied at three different levels alone and combined to each other. The experimental design was arranged in factorial complete randomized blocks using contamination, organic and mineral fertilizer levels, and their combination as categorical factors. The distribution of metal fractions and their bioavailability in soils and bioaccumulation in wheat grains were evaluated. Soil alkalinity, the contents of soil organic carbon and nitrogen, available phosphorus, and soil micronutrients were significantly improved under vermicompost and compost compared to mineral fertilizer and control. Vermicompost was more effective than compost in reducing metals bioavailability in contaminated soils by increasing the immobilized organic fractions, but it regressed when combined with mineral fertilizers. The bioavailability of the naturally occurring metal levels in uncontaminated soil did not change significantly compared to contaminated soil. Likewise, wheat yield, plant biomass, and nutrient enrichment in wheat grains improved due to enhanced soil nutrient availability. These composted agro-industrial residues, by-products from food industries, can be classified as environmentally-friendly soil amendments for their great potential to enrich soil nutrients, reduce mineral fertilizer addition, enhance plant growth, and stabilize Cr, Cd, and Pb in contaminated calcareous soils under wheat plants.

Optimization of Methylene Blue Ultrasound-Assisted Adsorption onto Magnetic Sugarcane Bagasse Activated Carbon Using Response Surface Methodology

This study focused on the optimization of methylene blue removal on a magnetic activated carbon from the carbon-rich agro-industrial residue, sugarcane bagasse, synthesized by microwave method. The adsorption process was assisted by ultrasound. The magnetic sugarcane bagasse activated carbon (MSB) was characterized by FTIR and SEM-EDX. Based on FTIR results, the functional groups found in magnetic sugarcane bagasse activated carbon are O-H, C=C, C-O, and Fe-O. The SEM results show that MSB is porous with a rough surface. In addition, EDX data found the presence of three main elements, namely C, O, and Fe. Response Surface Methodology (RSM) Box-Behnken Design was applied to analyze the effects of three parameters, including adsorbent dosage (50-100 mg/L), ultrasonic power (100-200 W), and contact time (30-60 min). The obtained optimum conditions of the adsorption process were the sonication power of 155.65 W, the adsorbent dosage of 89.77 mg/L, and the sonication time of 57,81 minutes. The results indicated that the parameters of adsorbent dosage, ultrasonic power, and contact time influenced the response (qe and methylene blue removal).

Efficient conversion of black cumin cake from industrial waste into lipopeptide biosurfactant by Pseudomonas fluorescens

Most biosurfactants are obtained using costly culture media, which limits their wider industrial use. In the present study, a low-cost culture medium, containing the agro-industrial residue black cumin cake, was developed for amphisin production by Pseudomonas fluorescens DSS73. By using black cumin cake as the substrate, not only was the production cost reduced but also a higher production yield was achieved. A Box-Behnken experimental design was applied to maximize lipopeptide biosurfactant production. The optimal conditions for amphisin production, such as black cumin cake (6.6%) and NaCl (8.0 mM) concentration, and cultivation time (6.5 days), were determined. Yield of amphisin production, performed in optimal conditions, reached 16.51 ± 0.49 g/L. Such high production has not been evidenced previously for Pseudomonas lipopeptide biosurfactants. Moreover, active utilization of the substrate, observed with the aid of scanning electron microscopy (SEM), documented by numerous holes and pitting on the black cumin cake surface, was confirmed. Finally, antifungal activity of amphisin against Aspergillus carbonarius was demonstrated. Hence, amphisin production by P. fluorescens was achieved with statistical optimization using an inexpensive agro-industrial by-product for the first time.

Removal of caffeine using agro-industrial residues in fixed-bed columns: Improving the adsorption capacity and efficiency by selecting adequate physical and operational parameters

Developing effective water treatment technologies is indispensable to mitigate the negative impacts that aqueous contaminants can have on the environment. In this work, the potential of agro-industrial residues such as peanut shells, rice husk, coconut fiber and corn cob was investigated for removing caffeine from water using fixed-bed columns. The effects of the following parameters on the adsorptive performance of the columns were studied: particle size of the residues (Ps = 595–710, 710–1400, 1400–2000 μm), bed height (Z = 10, 15, 20 cm), flow rate (Q = 0.5, 1.0, 1.5 mL/min), and caffeine concentration (Co = 5, 10, 15 mg/L). Results demonstrated that the effect of particle size was influenced by the bulk density of the material (ρ) and bed porosity (ԑ). Increasing the bed height and decreasing the flow rate led to longer residence times and higher adsorption capacities. Increasing the caffeine influent concentration, increased the adsorption capacity, but reduced the removal efficiency. Columns packed with coconut fiber, Ps = 710–1400 μm (ρ = 0.102, ԑ = 0.30), Z = 20 cm, Q = 0.5 mL/min, and Co = 15 mg/L resulted in the best adsorption capacity (0.326 mg/g) and removal efficiency (47 %). The Adams-Bohart, Thomas, Yoon-Nelson, and Dose-Response models were used to describe the dynamic adsorption of the columns. Thomas' model predicted adsorption capacities closer to the experimental ones (R2 = 0.996, for 0.326 mg/g). The results obtained also open the possibility of defining criteria for assessing materials for removing aqueous pollutants in continuous processes.

Comparison of metagenomes from fermentation of various agroindustrial residues suggests a common model of community organization.

The liquid residue resulting from various agroindustrial processes is both rich in organic material and an attractive source to produce a variety of chemicals. Using microbial communities to produce chemicals from these liquid residues is an active area of research, but it is unclear how to deploy microbial communities to produce specific products from the different agroindustrial residues. To address this, we fed anaerobic bioreactors one of several agroindustrial residues (carbohydrate-rich lignocellulosic fermentation conversion residue, xylose, dairy manure hydrolysate, ultra-filtered milk permeate, and thin stillage from a starch bioethanol plant) and inoculated them with a microbial community from an acid-phase digester operated at the wastewater treatment plant in Madison, WI, United States. The bioreactors were monitored over a period of months and sampled to assess microbial community composition and extracellular fermentation products. We obtained metagenome assembled genomes (MAGs) from the microbial communities in each bioreactor and performed comparative genomic analyses to identify common microorganisms, as well as any community members that were unique to each reactor. Collectively, we obtained a dataset of 217 non-redundant MAGs from these bioreactors. This metagenome assembled genome dataset was used to evaluate whether a specific microbial ecology model in which medium chain fatty acids (MCFAs) are simultaneously produced from intermediate products (e.g., lactic acid) and carbohydrates could be applicable to all fermentation systems, regardless of the feedstock. MAGs were classified using a multiclass classification machine learning algorithm into three groups, organisms fermenting the carbohydrates to intermediate products, organisms utilizing the intermediate products to produce MCFAs, and organisms producing MCFAs directly from carbohydrates. This analysis revealed common biological functions among the microbial communities in different bioreactors, and although different microorganisms were enriched depending on the agroindustrial residue tested, the results supported the conclusion that the microbial ecology model tested was appropriate to explain the MCFA production potential from all agricultural residues.

Biomethane Production and Utilization Pathways: an MDCA-based Impact Assessment in Sardinia, Italy

Biogas from the anaerobic digestion of organic substrates represents a renewable and sustainable fuel widely deployed in Sardinia, supported by the high share of rural areas and the generation of agro-industrial residues and by-products. On the wave of new economic incentives, interest is gradually shifting to biomethane. Nonetheless, the possible uses of biomethane are compelled by the local energy system, which defects in the implementation of the natural gas grid and gas fuelling stations. This is the reason why heat and power production may still be considered one of the most plausible biomethane utilization. Multiple options for upgrading biogas into biomethane exist. Chemical absorption represents an established and reliable upgrading solution. However, innovative alternatives such as biological methanation have emerged characterized by high sustainability and versatility. In the present paper, six scenarios for biomethane generation and utilization are presented and analysed to determine an integrated impact benchmark for each of them. The impact assessment is structured in criteria that depict the environmental, economic, technological and social dimensions. It is carried out using the Multi-criteria Decision Analysis. An in-depth literature review allowed to identify quantitative and qualitative indicators for each dimension according to a rationale described in the paper. The results describe the processes and technologies involved and determine the integrated impacts for the considered scenarios. The method adopted emphasizes the regional worth of the assessment process, and the critical importance of collecting technological data at the pilot or commercial scale, given the distinctiveness of the experiences developed at the laboratory-scale.

Sustainability approaches for agrowaste solution: Biodegradable packaging and microbial polysaccharides bio-production

Global growth impacts on the increased use and demand for natural resources, requiring solutions for the high volume of industrial waste and by-products generated from the most diverse commercial areas, mainly the food sector. Among the main residues with a large volume generated, those from fruit processing, grain cleaning in processing units, vegetables, and discards from the animal production industry stood out. Approximately 1.3 billion all food produced worldwide is lost or wasted per year being fruits, vegetables, roots, and tubers responsible for about half of the total amount. Many of these by-products have interesting nutrients in their composition such as fibers, proteins, and bioactive compounds. An interesting example is the sugarcane bagasse. Fibrous residue, derived from sugarcane extraction, the bagasse represents about 30–34 % of the total sugarcane mass. This is one of the most abundant cellulosic residues and contains approximately 39 % of cellulose, 28 % of hemicellulose, and 18 % of lignin. Therefore, as well as the bagasse, several residues from agroindustrial can be considered promising alternative substrates, being valuable sources for the development of high-value-added products, such as biopolymers, bioenergy, and chemical products. In addition, the reuse of agroindustrial wastes may be considered an attractive option for reducing the environmental impact caused by their generation. In the case of biopolymers, the energy savings of bio-based polymers is around 20–50 GJ/t of polymer. In this review, we have selected two commercially promising approaches to the application and use of agroindustrial residues, aiming their use for biodegradable packaging and microbial polysaccharides bio-production, improving overall sustainability and economic aspects of the scientific research, technology and modern industry.

Study of the activity and stability of sulfonated carbon catalyst from agroindustrial waste in biodiesel production: Influence of pyrolysis temperature on functionalization

The influence of pyrolysis temperature on the activity and catalytic stability of sulfonated biochar, from the agro-industrial residue murumuru kernel shell, was evaluated in the esterification reaction. Carbonaceous materials were synthesized by direct pyrolysis at 450, 600 and 750 °C and functionalized with sulfuric acid at 200 °C for a 4 h period. The materials were characterized by density of sulfonic groups, SEM, EDS, Elementary Analysis, ATR-FTIR, Raman Spectroscopy, TG and XPS analysis. The data obtained showed that the functionalization occurred directly in the carbon chain of biochar, evidencing that higher carbonization temperatures resulted in carbonaceous catalysts of more stable polycondensed nature. The catalyst synthesized at 750 °C achieved conversion of 98.35% ± 1.105 and maintained in the third reaction cycle conversion of 89.35% ± 1.197. This catalyst also showed the highest content of sulfur groups, even after reuse processes. The increment of temperature and time in the reaction medium was able to improve the reuse capacity of relatively low stability catalysts. Thus, the results obtained show the impact of pyrolysis temperature on obtaining catalysts with greater activity and catalytic stability in esterification reactions, and in this way provide very important subsidies for the development of new heterogeneous sulfonated carbon-based catalysts, applied in the biodiesel production process.

Crop waste management proposal in rice systems at the department of Cordoba, Colombia

The claim for food increases with the waste caused by its production. Rice is appetized but the agro-industrial residue, such as straw and husk, becomes a problem when they're not properly managed. However, renewable source demands grew, indeed, the chains of rice residue as cellulose, lignin, hemicellulose, carbon, and silica could be transformed into: fuel, power generation, gas production, paper manufactory, and fertilizer for the production of fungi and building material.The industrial implementation of rice residue management worldwide has a lack. In this case, it was observed more closely the rice cultivation in a local region of Colombia. The aim of this research was to present the current market, challenges and the proposal of a proper management residue on a circular economy incorporated into Córdoba department rice market.The study was conducted through scientific and comprehensive insights on rice crop waste management options. The selection criteria of the articles were rice production, major components of rice paddy, straw, and husks, and waste disposal in rice systems. Farmers, researchers, federations, administration, and management, need to work on, improving the nutrients of the soil, the quality of the crop, and the management of the residue, the one that remains in the mills and the one that remains in the fields. Finally, in all processes, the required investment to obtain a product that meets current market requirements on renewable fuels or raw materials.

Initial Study of Fungal Bioconversion of guishe (Agave lechuguilla Residue) Juice for Bioherbicide Activity on Model Seeds

In agriculture, weed management is a significant concern because their uncontrolled proliferation decreases soil quality for food crops. Allelopathy is a natural phenomenon in which the activity of allelochemical compounds inhibits the germination and growth of invasive plants as a defense mechanism. Among allelochemicals are polyphenols, which may affect genetic material or crucial enzyme activities for proper physiological function. Agroindustrial residues are a vast source of polyphenolic compounds with allelochemical activity. The bagasse of Agave Lechuguilla, known as guishe, is an abundant residue in México. The guishe has been characterized before by its polyphenolic content. Based on that, a fungal bioconversion process was developed to increase the availability of the allelochemicals in the guishe juice. First, guishe juice was obtained by mechanical pressed and characterized by spectrophotometric analysis. Results showed (g/L): 5.62 flavonoids, 0.64 of hydrolyzable polyphenols, 12.67 of reducing sugars, and 23.3 total sugars. The compounds detected by HPLC-ESI-MS were pterostilbene, hydroxycaffeic, caffeoyltartaric, and 4-O-glucoside coumaric acids, considered allelopathic. After the fungal bioprocess, (+)-gallocatechin and 3,7-Dimethyl quercetin were detected as additional compounds of interest. The flavonoid and hydrolyzable polyphenol content were modified to the highest accumulation of 1.57 and 14.9 g/L at 72 h, meaning a 2.45- and 2.22-fold increase. A bioprocess guishe juice (BGJ) was obtained at the compound accumulation peak of 72 h and evaluated in an allelopathic assay on model seeds (tomato and corn). Results show that BGJ inhibits up to 96.67% of corn seeds and up to 76.6% of tomato seeds compared to positive control.

A preliminary evaluation of different residual biomass potential for energy conversion in a micro-scale downdraft gasifier

Residual biomass can be a promising alternative to replace fossil fuels for energy production. Through small-scale gasification systems it is possible to obtain a fuel gas from solid biomass that can be used for electrical and thermal energy generation. In this work, six different biomasses (five agro-industrial residues and A1 ENplus pellets) were tested in a lab-scale prototype. For each tested feedstock, elemental and ash analyses were carried out. The contaminant amount in the produced gas was measured as well as the mass and energy fluxes to calculate the gasification efficiency. The ratio between the pressure drop across the reactor and the gas flow raised to the square was introduced to compare the gasifier behavior at different power outputs. The results showed that with the exclusion of the tests run with cork, the other tested agro-industrial residues (pistachio shell, hemp and driftwood) performed acceptably in terms of efficiency, providing also a char with a carbon content over 70% as by-product.

Semi-Simultaneous Saccharification and Fermentation Improved by Lignin and Extractives Removal from Sugarcane Bagasse

Lignocellulosic biomass and agro-industrial residues are a source of fermentable sugars; however, pretreatments are needed to overcome biomass recalcitrance. This study evaluated the effect of sugarcane bagasse hydrolysis and fermentation in response to dilute acid pretreatment. In natura bagasse, extractive-free bagasse, partially delignified bagasse, and bagasse with added butylated hydroxytoluene antioxidant were pretreated with diluted acid and investigated in semi-simultaneous saccharification and fermentation (S-SSF). The effect of butylated hydroxytoluene (BHT) resulted in lower yields of inhibitors in the liquid fraction of the acid pretreatment (0.01 g L−1 of furfural, 0.01 g L−1 of 5-hydroxymethylfurfural, and 0.68 g L−1 of acetic acid). Partially delignified material and material with BHT resulted in biomass with low hemicellulose and lignin contents, indicating that BHT influenced lignin removal. Extractives removal showed benefits for the acid pretreatment, decreasing the dioxane-soluble material, and a higher yield of glucose and ethanol via S-SSF for the partially delignified material. Enzymatic saccharification of partially delignified material showed 87% of cellulose conversion (24 h with 15 FPU/g), and after 48 h of S-SSF (25 FPU/g), residual 7.06 g L−1 of glucose and production of 15.17 g L−1 of ethanol were observed. The low content of extractives, lignin, and dioxane soluble material resulted in better cellulose accessibility and ethanol yield. Chemical compounds can help remove lignin from biomass favoring ethanol production by S-SSF.

Emerging Contaminants and Their Removal from Aqueous Media Using Conventional/Non-Conventional Adsorbents: A Glance at the Relationship between Materials, Processes, and Technologies

Emerging contaminants (ECs) are causing negative effects on the environment and even on people, so their removal has become a priority worldwide. Adsorption and the associated technologies where this process occurs (filtration/biofiltration) have gained great interest, due to its low cost, easy operation, and effectiveness mainly in the removal (up to 100%) of lipophilic ECs (log Kow > 4). Activated carbon continues to be the most efficient material in the removal of ECs (>850 mg/g). However, other conventional materials (activated carbon, clays, zeolites) and non-conventional materials (agro-industrial/forestry/industrial residues, nanomaterials, among others) have shown efficiencies greater than 90%. Adsorption depends on the physicochemical properties of the materials and ECs. Thus, physical/chemical/thermal modifications and nanomaterial synthesis are the most used procedures to improve adsorption capacity. A material with good adsorptive properties could be used efficiently in filtration/biofiltration technologies. Agro-industrial residues are promising alternatives to be used in these technologies, due to their high availability, low toxicity, and adsorption capacities (up to 350 mg/g). In filtration/biofiltration technologies, the material, in addition to acting as adsorbent, plays a fundamental role in operation and hydraulics. Therefore, selecting the appropriate material improves the efficiency/useful life of the filter/biofilter.

Evaluation of Hot Pressing Processing by Physical Properties of Ecofriendly Composites Reinforced by Eucalyptus Sawdust and Chamotte Residues.

The particleboard industry consumes large amounts of raw material, and this type of product consumption has been increasing over the last few years. The research for alternative raw materials becomes interesting, since most of the resources come from planted forests. In addition, the investigation of new raw materials must take into account environmentally correct solutions, such as the use of alternative natural fibers, use of agro-industrial residues, and resins of vegetable origin. The objective of this study was to evaluate the physical properties of panels manufactured by hot pressing using eucalyptus sawdust, chamotte, and polyurethane resin based on castor oil as raw materials. Eight formulations were designed with variations of 0, 5, 10, and 15% of chamotte, and two variations of resin with 10% and 15% of volumetric fraction. Tests of gravimetric density, X-ray densitometry, moisture content, water absorption, thickness swelling, and scanning electron microscopy were carried out. Through the results it can be noticed that the incorporation of chamotte in the manufacture of the panels increased the water absorption and the swelling in thickness, around 100% and the use of 15% of resin decreased, more than 50%, the values of these properties. X-ray densitometry analyzes showed that the addition of chamotte alters the density profile of the panel. In addition, the panels manufactured with 15% resin were classified as P7, the most demanding type on EN 312:2010 standard.

Effect of broccoli fresh residues-based extracts on the postharvest quality of cherry tomato (Solanum lycopersicum L.) fruits

Agroindustrial residues such as cruciferous plant residues are important for postharvest treatments and of great interest because of their bioactive compounds with antimicrobial and antifungal activity, which can be used as an alternative to the use of chemical agents to treat pathogens during tomato postharvest. Cherry tomato fruit has a short shelf-life due to the action of microorganisms and high respiration rate during storage. For this reason, the effect of broccoli fresh residues-based extracts on the postharvest quality of cherry tomato fruits and their inhibition effect in vivo against Botrytis cinerea were evaluated. Extracts were obtained from fresh broccoli residues using ultrasound and different solvents (ethanol and methanol, 30% v/v), these were used as immersion treatments, and fruits were stored at 21 °C. The results showed that the application of broccoli residue extracts on cherry tomato fruits generated a decrease in weight loss and maintained firmness, color, chemical content (pH, TSS, TA, and TA/TSS ratio), phenolic compounds, and antioxidant capacity compared to untreated (control) tomato fruits. Additionally, extracts showed a fungistatic effect against Botrytis cinerea under in vivo conditions. Therefore, broccoli extracts, particularly 20 mg L−1 methanol/ultrasound, can be used as postharvest treatments for cherry tomato preservation to 36 days of storage.

Improved bioremediation of PCDD/Fs contaminated soil by mycelium-free liquids induced by agro-industrial residues

Mycoremediation using white rot fungi is a sustainable method for treating PCDD/F-contaminated soil. In this study, five agricultural wastes were used to cultivate Phanerochaete chrysosporium (PC) and Pleurotus pulmonarius (PP), and after six days of submerged cultivation, mycelium-free liquids (MFLs) were obtained. These MFLs were then used to treat non-sterilized PCDD/F-contaminated soil (7100 ng I-TEQ/kg). The removal efficiencies were found to be comparable to those of a regular medium, with average efficiencies of ~45 % and 42 % for PC and PP, respectively, after 96 h. The highest removal efficiency reached 91 % and 55 % (mass and toxic concentrations) when the MFLs were induced with spent coffee grounds and green tea residue. The removal mechanism was found to be biased towards oxidation rather than dehalogenative reduction. Also, the addition of borate-fructose complex as a mediator increased the removal efficiency by 17 %. This method offers a promising and sustainable way to remediate PCDD/F-contaminated soil.

Characterization of amylase, lipase and xylanase produced by actinobacteria cultivated in licuri [Syagrus coronata - (Martius) Beccari] residues

In order to seach for different microbial sources of enzymes, Arthrobacter polychromogenes CDPI-30 and Streptomyces violaceoruber CDPA-32 were individually cultivated in licuri [Syagrus coronata - (Martius) Beccari] residues. It was possible to detect some enzymes but amylase, lipase and xylanase were selected for a basic characterization. The optimum conditions were observed at pH 6 and 7 and 40 – 70 °C for amylases, pH 4 – 6 and 50 – 90 °C for lipases and pH 8 and 10 and 20 – 50 °C for xylanases. The best stabilities, evaluated under different conditions were, in a way, a result from the optimal conditions. Additionally, substrate saturation was not observed for soluble starch and xylan until 15 mg/mL and p-nitrophenyl palmitate until 9.95 µmol/mL. These results indicate that both, actinobacteria and the agroindustrial residues, are good choices to produce basic industrial enzymes.