Removal of heavy metal ions from wastewaters: A review

The applications of copper (Cu) and Cu-based nanoparticles, which are based on the earth-abundant and inexpensive copper metal, have generated a great deal of interest in recent years, especially in the field of catalysis. The possible modification of the chemical and physical properties of these nanoparticles using different synthetic strategies and conditions and/or via postsynthetic chemical treatments has been largely responsible for the rapid growth of interest in these nanomaterials and their applications in catalysis. In addition, the design and development of novel support and/or multimetallic systems (e.g., alloys, etc.) has also made significant contributions to the field. In this comprehensive review, we report different synthetic approaches to Cu and Cu-based nanoparticles (metallic copper, copper oxides, and hybrid copper nanostructures) and copper nanoparticles immobilized into or supported on various support materials (SiO2, magnetic support materials, etc.), along with their applications i...

http://pubs.acs.org/doi/pdfplus/10.1021/acs.chemrev.5b00482

Cu and Cu-Based Nanoparticles: Synthesis and Applications in Catalysis.

This review focuses on some important and challenging aspects of soil extracellular enzyme research. We report on recent discoveries, identify key research needs and highlight the many opportunities offered by interactions with other microbial enzymologists. The biggest challenges are to understand how the chemical, physical and biological properties of soil affect enzyme production, diffusion, substrate turnover and the proportion of the product that is made available to the producer cells. Thus, the factors that regulate the synthesis and secretion of extracellular enzymes and their distribution after they are externalized are important topics, not only for soil enzymologists, but also in the broader context of microbial ecology. In addition, there are many uncertainties about the ways in which microbes and their extracellular enzymes overcome the generally destructive, inhibitory and competitive properties of the soil matrix, and the various strategies they adopt for effective substrate detection and utilization. The complexity of extracellular enzyme activities in depolymerising macromolecular organics is exemplified by lignocellulose degradation and how the many enzymes involved respond to structural diversity and changing nutrient availabilities. The impacts of climate change on microbes and their extracellular enzymes, although of profound importance, are not well understood but we suggest how they may be predicted, assessed and managed. We describe recent advances that allow for the manipulation of extracellular enzyme activities to facilitate bioremediation, carbon sequestration and plant growth promotion. We also contribute to the ongoing debate as to how to assay enzyme activities in soil and what the measurements tell us, in the context of both traditional methods and the newer techniques that are being developed and adopted. Finally, we offer our collective vision of the future of extracellular enzyme research: one that will depend on imaginative thinking as well as technological advances, and be built upon synergies between diverse disciplines.

Soil enzymes in a changing environment: Current knowledge and future directions

The public demand for color-free waste discharge to receiving waters and tougher color standards have made decolorization of a variety of industrial wastes a top priority. Unfortunately, with the complicated color-causing compounds, the decolorization of these wastes is a difficult and challenging task. This article first describes the background information of dye molecules and dye waste characteristics. The methods for color measurements and standards are then discussed. Different techniques including almost all the known physical, chemical and biological techniques are described for decolorization. Each process alone may not be able to meet the requirements. A combination of these processes, for example, chemical-biological, biological-chemical, chemical-physical, chemical-chemical, etc. is often used. The formation of intermediates during the decolorization process is emphasized. These byproducts may be more toxic than the parent compounds. Thus, the extent of the mineralization in waste decolorizatio...

Decolorization of Wastewater

Clays and oxide minerals as catalysts and nanocatalysts in Fenton-like reactions — A review

Effect of EDTA and Fe-EDTA complex concentration on TCF Kraft mill effluent degradability. Batch and continuous treatments.

The SARS-CoV-2 virus outbreak revealed that these nano-pathogens have the ability to rapidly change lives. Undoubtedly, SARS-CoV-2 as well as other viruses can cause important global impacts, affecting public health, as well as, socioeconomic development. But viruses are not only a public health concern, they are also a problem in agriculture. The current treatments are often ineffective, are prone to develop resistance, or cause considerable adverse side effects. The use of nanotechnology has played an important role to combat viral diseases. In this review three main aspects are in focus: first, the potential use of nanoparticles as carriers for drug delivery. Second, its use for treatments of some human viral diseases, and third, its application as antivirals in plants. With these three themes, the aim is to give to readers an overview of the progress in this promising area of biotechnology during the 2017-2020 period, and to provide a glance at how tangible is the effectiveness of nanotechnology against viruses. Future prospects are also discussed. It is hoped that this review can be a contribution to general knowledge for both specialized and non-specialized readers, allowing a better knowledge of this interesting topic.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/gch2.202000049

Advanced Material Against Human (Including Covid-19) and Plant Viruses: Nanoparticles As a Feasible Strategy.

Biodegradation of pesticides by Actinobacteria and their possible application in biobed systems.

The use of biochar has traditionally been focused on agronomic applications. Today it is possible to find a wide range of research devoted to study the use of biochar in the most varied fields. This is mainly due to its properties and the diversity of materials that can be used in their synthesis. Also, the conditions of operation in the process of synthesis (pyrolysis) can be easily modified to obtain a product with the desired features for a given application. Consequently, this review examines the biochar properties that are relevant to its applicability in three areas of high industrial interest; control release and immobilization, where it could serve as alternative, cheap and renewable support material to existing conventional types.

Biochar as a Renewable Matrix for the Development of Encapsulated and Immobilized Novel Added-Value Bioproducts

Potato waste was processed and used as a sole substrate for simultaneously producing antifungals and biopigments using Streptomyces spp. Out of three different Streptomyces isolates, strain SO6 stood out due to its ability to produce antifungals against economically important fungal phytopathogens and intracellular biopigments using potato waste powders without additional nutrients. This strain also showed the potential to secrete a broad range of enzymes for fermentation of eight sugars that could be involved in potato waste bioconversion. The results of the fermentation assay indicated that Streptomyces sp. strain SO6 degrades potato wastes during submerged fermentation, diminishing total dry weight and increasing reducing sugars from 0.3 to 3.6 mg·mL-1 and total proteins from 70.6 to 187.7 μg·mL-1. The results showed that Streptomyces strain SO6 was able to convert the potato waste into 0.96 mg·g-1 of diffusible antifungals and 1.75 mg·g-1 of reddish-purple biopigments. On the contrary, an absence of pigment production was observed during the fermentation of the commercial medium used as reference. According to our results, replacement of commercial culture media with available low-cost agroindustrial wastes for producing bioactive chemicals is a real opportunity to enhance the Streptomyces pigment production and antibiotic sustainability with cost-competitiveness. To our knowledge, this is the first report on the simultaneous production of biopigments and diffusible antifungal antibiotics produced by Streptomyces spp. using potato solid waste as the sole nutrient source.

/pdf/bioconversion-of-potato-solid-waste-into-antifungals-and-5daauzjzz9.pdf

María Cristina Diez

Papers

Effect of EDTA and Fe-EDTA complex concentration on TCF Kraft mill effluent degradability. Batch and continuous treatments.

Advanced Material Against Human (Including Covid-19) and Plant Viruses: Nanoparticles As a Feasible Strategy.

Biodegradation of pesticides by Actinobacteria and their possible application in biobed systems.

Biochar as a Renewable Matrix for the Development of Encapsulated and Immobilized Novel Added-Value Bioproducts

Bioconversion of potato solid waste into antifungals and biopigments using Streptomyces spp.