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Due to their widespread occurrence and the inadequate removal efficiencies by conventional wastewater treatment plants, emerging contaminants (ECs) have recently become an issue of great concern. Current ongoing studies have focused on different physical, chemical, and biological methods as strategies to avoid exposing ecosystems to significant long-term risks. Among the different proposed technologies, the enzyme-based processes rise as green biocatalysts with higher efficiency yields and lower generation of toxic by-products. Oxidoreductases and hydrolases are among the most prominent enzymes applied for bioremediation processes. The present work overviews the state of the art of recent advances in enzymatic processes during wastewater treatment of EC, focusing on recent innovations in terms of applied immobilization techniques, genetic engineering tools, and the advent of nanozymes. Future trends in the enzymes immobilization techniques for EC removal were highlighted. Research gaps and recommendations on methods and utility of enzymatic treatment incorporation in conventional wastewater treatment plants were also discussed.

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Pyroligneous acid (PA) was evaluated as a potential alternative to therapeutic antibiotics in poultry. Antimicrobial activity of PA was studied at acidic pH (2.0) and neutral pH (7.0) of the liquid against Salmonella enterica and Lactobacillus acidophilus. Acidic PA gave a MIC value of 0.8% (v/v) and 1.6% (v/v), and neutralized PA gave a MIC value of 1.6% (v/v) and 3.2% (v/v) against S. enterica and L. acidophilus respectively. Acidic PA was evaluated at different concentrations in a simulated poultry digestive tract and cecal fermentation to study its effect on the cecal microflora and fermentation profile. PA at a concentration of 1.6% (v/v) completely inhibited S. enterica and was also found to have a similar effect on lactobacilli count as compared with the control (p = 0.17). Additionally, PA at this concentration was found not to have a significant effect on acetic acid production after 24 h of cecal fermentation (p = 0.20). Graphical abstract.

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Titanium dioxide particles (TiO2) are widely used to produce whitens (titanium white) and different class of nanomaterials (semiconductors, photo catalysts and nanotubes). Nanomaterials are excellent adsorbents and catalysts with a wide range of applications. However, these are reported to induce biological and genetic alterations among several invertebrate groups. Invasive species such as zebra mussels can be used as model organisms to study the behavior of particles and nanoparticles (NPs) due to their wide distribution; mussels have been extensively used for monitoring water pollution. In the present study, TiO2 particles were dispersed and added to a Chlorella culture to emulate a natural scenario. To study the reaction of zebra mussels to different TiO2 concentrations, they were fed with 0.35, 0.7 and 3.5 mgTiO2/L of the suspension for 3days and the titanium was measured in the water column, mussels and sediments with ICP-AES. Zebra mussels obtained from the Port of Quebec had up 61.62mgTi/kg wet tissue at the time of capture. After 10days of depuration, they had from 0.23 to 16.28mgTi/kg wet tissue. Mussels accumulated TiO2 after 36h of exposition as a function of TiO2 concentration, but mussels did not present significant mortality due to TiO2 toxicity until concentrations higher than 0.7ppm. A second set of experiments was run to understand the TiO2 pathway attached to microalgae vs free TiO2. Results indicated that mussels accumulated slightly more Ti when it was mixed with microalgae. However, the statistical difference was non- significant. A 100 times higher accumulation of Ti in sediments was identified when mussels are present. Thus, it was concluded that the sedimentation of TiO2 is enhanced by the zebra mussels' filtration activity.

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Coffee has been for decades the most commercialized food product and most widely consumed beverage in the world, with over 600 billion cups served per year. Before coffee cherries can be traded and processed into a final industrial product, they have to undergo postharvest processing on farms, which have a direct impact on the cost and quality of a coffee. Three different methods can be used for transforming the coffee cherries into beans, known as wet, dry, and semi-dry methods. In all these processing methods, a spontaneous fermentation is carried out in order to eliminate any mucilage still stuck to the beans and helps improve beverage flavor by microbial metabolites. The microorganisms responsible for the fermentation (e.g., yeasts and lactic acid bacteria) can play a number of roles, such as degradation of mucilage (pectinolytic activity), inhibition of mycotoxin-producing fungi growth, and production of flavor-active components. The use of starter cultures (mainly yeast strains) has emerged in recent years as a promising alternative to control the fermentation process and to promote quality development of coffee product. However, scarce information is still available about the effects of controlled starter cultures in coffee fermentation performance and bean quality, making it impossible to use this technology in actual field conditions. A broader knowledge about the ecology, biochemistry, and molecular biology could facilitate the understanding and application of starter cultures for coffee fermentation process. This review provides a comprehensive coverage of these issues, while pointing out new directions for exploiting starter cultures in coffee processing.

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