Bioremediation strategies against pesticides: An overview of current knowledge and innovations.

Pesticides pose significant risks to both human health, such as cancer, neurological disorders, and endocrine disruption, and ecosystems, through the destruction of beneficial insects, contamination of soil and water, and impact on non-target species. In the face of escalating pesticide pollution, there is an urgent need for multifaceted approaches to address the issue. Bioremediation emerges as a potent tool in the environmental pollution mitigation arsenal. Ideally aiming for the complete decomposition of pesticides into harmless molecules, bioremediation encompasses diverse approaches - from bioabsorption, bioadsorption, and biotransformation using enzymes and nanoenzymes to comprehensive degradation facilitated by microorganisms such as bacteria, fungi, macro- and microalgae, or phytoremediation. Exploring nature's biodiversity offers a promising avenue to find solutions to this pressing human-induced problem. The acceleration of biodegradation necessitates identifying and developing efficient organisms, achieved through bioprospection and targeted modifications. Specific strategies to enhance process efficiency and throughput include optimizing biomass production, strategic inoculation in diverse environments, and employing bioreactor systems for processing heavily contaminated waters or soils. This comprehensive review presents various bioremediation approaches, emphasizing the importance of microorganisms' exploration and new technologies development, including current innovations and patents to effectively combat pesticide pollution. Furthermore, challenges regarding the effective implementation of these technologies are also addressed.

Green Synthesis of Silver Nanoparticles Mediated by Punica granatum Peel Waste: An Effective Additive for Natural Rubber Latex Nanofibers Enhancement.

Pomegranate waste poses an environmental challenge in Arequipa. Simultaneously, interest in sustainable materials like natural rubber latex (NRL) is growing, with Peruvian communities offering a promising source. This study explores the green synthesis of silver nanoparticles (AgNPs) using pomegranate peel extract and their incorporation into NRL nanofibers for enhanced functionalities. An eco-friendly process utilized silver nitrate and pomegranate peel extract as a reducing and capping agent to synthesize AgNPs. The resulting AgNPs and NRL/AgNPs nanofibers were characterized using imaging and spectroscopic techniques such as UV-vis, TGA, FTIR, XRD, Raman, SEM, and DLS. Green-synthesized AgNPs were spherical and crystalline, with an average diameter of 59 nm. They showed activity against K. pneumoniae, E. coli, B. cereus, and S. aureus (IC50: 51.32, 4.87, 27.72, and 69.72 µg/mL, respectively). NRL and NRL/AgNPs nanofibers (300-373 nm diameter) were successfully fabricated. The composite nanofibers exhibited antibacterial activity against K. pneumoniae and B. cereus. This study presents a sustainable approach by utilizing pomegranate waste for AgNP synthesis and NRL sourced from Peruvian communities. Integrating AgNPs into NRL nanofibers produced composites with antimicrobial properties. This work has potential applications in smart textiles, biomedical textiles, and filtration materials where sustainability and antimicrobial functionality are crucial.

Microalgae-mediated biofixation as an innovative technology for flue gases towards carbon neutrality: A comprehensive review.

Microalgae-mediated industrial flue gas biofixation has been widely discussed as a clean alternative for greenhouse gas mitigation. Through photosynthetic processes, microalgae can fix carbon dioxide (CO2) and other compounds and can also be exploited to obtain high value-added products in a circular economy. One of the major limitations of this bioprocess is the high concentrations of CO2, sulfur oxides (SOx), and nitrogen oxides (NOx) in flue gases, according to the origin of the fuel, that can inhibit photosynthesis and reduce the process efficiency. To overcome these limitations, researchers have recently developed new technologies and enhanced process configurations, thereby increased productivity and CO2 removal rates. Overall, CO2 biofixation rates from flue gases by microalgae ranged from 72 mg L-1 d -1 to over 435 mg L-1 d-1, which were directly influenced by different factors, mainly the microalgae species and photobioreactor. Additionally, mixotrophic culture have shown potential in improving microalgae productivity. Progress in developing new reactor configurations, with pilot-scale implementations was observed, resulting in an increase in patents related to the subject and in the implementation of companies using combustion gases in microalgae culture. Advancements in microalgae-based green technologies for environmental impact mitigation have led to more efficient biotechnological processes and opened large-scale possibilities.

Aspartic protease supplementation enhancing the performance, carcass characteristics, nutrient digestibility and economic viability, without changing blood parameters and salivary cortisol of pigs.

Aiming to study the performance, carcass characteristics, nutrient digestibility, blood parameters, salivary cortisol levels, and economic viability of pigs administered aspartic protease, a total of 135 pigs were housed in pens in a randomized block design, divided into five treatments with nine replications. The experimental diets were positive control (PC), basic diet with a 5.0% reduction in protein and amino acid requirements; negative control (NC) with a 7.5% reduction in protein and amino acid requirements; NC + 100 g/mT of aspartic protease (NC100); NC + 150 g/mT of aspartic protease (NC150); and NC + 200 g/mT of neutral serine protease (NC200). The inclusion of protease, independently of the source and amount, increased the average daily weight gain (P < 0.05) of animals compared with the control treatments (PC and NC), improved feed conversion (P < 0.05) in early stages, and improved diet digestibility (P < 0.05) compared with the PC. Treatment with NC150 and NC200 resulted in greater carcass weights (P < 0.05) than treatment with the PC. NC100 led to a greater carcass yield than PC (P < 0.05), and NC150 resulted in a greater loin eye area than PC (P < 0.05). No differences (P > 0.05) in the blood parameters or salivary cortisol levels were found. Regarding economic viability, proteases increased the profitability, with NC150 leading to the best results. Thus, the use of aspartic proteases is recommended to improve performance and further facilitate pork production.

Biogenic Synthesis of Copper Nanoparticles: A Systematic Review of Their Features and Main Applications.

Nanotechnology is an innovative field of study that has made significant progress due to its potential versatility and wide range of applications, precisely because of the development of metal nanoparticles such as copper. Nanoparticles are bodies composed of a nanometric cluster of atoms (1-100 nm). Biogenic alternatives have replaced their chemical synthesis due to their environmental friendliness, dependability, sustainability, and low energy demand. This ecofriendly option has medical, pharmaceutical, food, and agricultural applications. When compared to their chemical counterparts, using biological agents, such as micro-organisms and plant extracts, as reducing and stabilizing agents has shown viability and acceptance. Therefore, it is a feasible alternative for rapid synthesis and scaling-up processes. Several research articles on the biogenic synthesis of copper nanoparticles have been published over the past decade. Still, none provided an organized, comprehensive overview of their properties and potential applications. Thus, this systematic review aims to assess research articles published over the past decade regarding the antioxidant, antitumor, antimicrobial, dye removal, and catalytic activities of biogenically synthesized copper nanoparticles using the scientific methodology of big data analytics. Plant extract and micro-organisms (bacteria and fungi) are addressed as biological agents. We intend to assist the scientific community in comprehending and locating helpful information for future research or application development.

Fine resolution analysis of bacterial communities associated with Neochloris oleoabundans culture and insights into terpenes as contamination control agents.

Biological contamination is one of the main bottlenecks in microalgae production, reducing quality and productivity and sometimes leading to the complete loss of the cultures. Selecting terpenes can be a pathway toward eco-friendly contamination control in microalgae cultures. This work evaluated the presence of bacterial contaminants in N. oleoabundans cultures through HTS and 16 S analysis and their susceptibility to six natural terpenes (α-pinene, ß-pinene, limonene, trans-cinnamaldehyde, linalool, and eugenol). The principal phyla identified were Proteobacteria, Bacteroidetes, and Actinobacteria, and based on these data, 89 bacterial isolates of seven genera were obtained (36 Aureimonas sp., 27 Microbacterium sp., 5 Pseudomonas sp., 9 Bacillus sp., 14 Shinella sp., 1 Brevundimonas sp., and 1 Exiguobacterium sp.) at 25ºC in the presence of light. It was possible to observe that Beta-pinene 50 mg L- 1 only inhibited Bacillus sp. In contrast, Alpha-pinene, Linalool, and Trans-cinnamaldehyde, at a concentration of 6.25 mg L- 1 efficiently inhibited most isolates. The inhibition percentages found were 79-99%.

Polyhydroxybutyrate production by Cupriavidus necator in a corn biorefinery concept.

The high costs of bioplastics' production may hinder their commercialization. Development of new processes with high yields and in biorefineries can enhance diffusion of these materials. This work evaluated the production of polyhydroxybutyrate (PHB) from the combination of milled corn starchy fraction hydrolysate and crude glycerol as substrates by the strain Cupriavidus necator LPB 1421. After optimization steps, maximum accumulation of 62 % of PHB was obtained, which represents 11.64 g.L-1 and productivity of 0.162 g.Lh-1. In a stirred tank bioreactor system with 8 L of operational volume, 70 % of PHB accumulation was reported, representing 14.17 g.L-1 of the biopolymer with 0.197 g.Lh-1 productivity. PHB recovery was conducted using a chemical digestion method, reaching >99 % purity. Therefore, the potential application of milled corn as substrate for PHB production was confirmed. The developed bioplastic process could be coupled to a bioethanol producing unit creating the opportunity of a sustainable and economic biorefinery.

Phosphorus release capacity in different dietary commercial phytases through performance and bone characteristics assessment of broiler chickens.

A trial was conducted to evaluate phosphorus release capacity in different commercial phytases throught performance and bone characteristics of broilers. A total of 2,400-day-old male Cobb 500® chicks were assigned in a completely randomized design with 12 dietary treatments ((1 to 5: with increasing levels of non-phytate phosphorus (NPP) (0.20; 0.25; 0.30; 0.35 and 0.40%) without phytase); and 6 to 12: with 0.20% supplemented with different commercial phytases), 8 replicates and 25 birds per pen. There was a linear increase (P<0.05) in the feed intake and body weight gain and a linear improvement (P<0.05) in the feed conversion ratio of broilers fed increasing NPP. The tested phytases did not release similar amounts of phytic phosphorus. Based on body weight gain response, 500 FTU/kg of diet releases a minimum and maximum of 0.074 to 0.152%, 0.062 to 0.157 and 0.059 to 0.169% of PP among the studied phytases in the periods from 1 to 21, 1 to 35 and 1 to 42 days, respectively. In conclusion, the commercial phytases released different concentrations of phytate phosphorus from the diets. Thus, is necessary to have a better method to evaluate phytase activity in order to avoid subnormal levels of available P in diets.

A non-waste strategy for enzymatic hydrolysis of cellulose recovered from domestic wastewater.

Cellulose is a potential resource to be recovered from wastewater treatment plants (WWTP). Enzyme formulations can be employed to hydrolyze cellulose into fermentable sugars, to be further used as biochemical building blocks or reducing its recalcitrance to further treatment processes. This study proposed the production, recovery and formulation of cellulase using domestic wastewater as culture medium and its application for the hydrolysis of cellulosic residues recovered from WWTPs. Cellulose was recovered from raw sanitary wastewater using a fine-mesh sieve (0.35 mm) and quantified through enzymatic hydrolysis and thermogravimetric analysis. The production, concentration and formulation of cellulase enzyme resulted in an enzymatic blend of endoglucanases (7.3 UFP/mL), cellobiohydrolases (7.4 UCMC/mL) and beta-glucosidases (4.4 UBGL/mL). The content of the recovered cellulosic material was 21.3% according to enzymatic hydrolysis and 27.7 for thermogravimetric results. The enzymatic hydrolysis of the WWTP residue using the produced cellulase (107.6 ± 10.2 mgreduc/gresidue) showed better results than using the commercial cellulase complex (66.4 ± 2.5 mgreduc/gresidue). This fact showed the potential of application of the produced enzyme for the hydrolysis of cellulosic residues recovered from WWTP processes. In a non-waste biorefinery approach, the generated hydrolysate can be further used for producing added-value biomolecules including biofuels and biochemicals.

Advances in microalgal cell wall polysaccharides: a review focused on structure, production, and biological application.

Microalgae have been shown to be useful in several biotechnological fields due to their feasible cultivation and high-value biomolecules production. Several substances of interest produced by microalgae, such as: proteins, lipids, and natural colorants, have already been explored. Based on the continuing demand for new natural molecules, microalgae could also be a valuable source of polysaccharides. Polysaccharides are extremely important in aquaculture, cosmetics, pharmaceutical, and food industries, and have great economic impact worldwide. Despite this, reviews on microalgal polysaccharide production, biological activity, and chemical structure are not abundant. Moreover, techniques of microalgal cultivation, coupled with carbohydrate production, need to be clarified in order to develop forward-looking technologies. The present review provides an overview of the main advances in microalgal cell wall polysaccharide production, as well as their associated potential biological applications and chemical structure. Several studies on future prospects, related to microalgae are presented, highlighting the key challenges in microalgal polysaccharide production.

Agro-industrial wastewater in a circular economy: Characteristics, impacts and applications for bioenergy and biochemicals.

The generation of agroindustrial byproducts is rising fast worldwide. The slaughter of animals, the production of bioethanol, and the processing of oil palm, cassava, and milk are industrial activities that, in 2019, generated huge amounts of wastewaters, around 2448, 1650, 256, 85, and 0.143 billion liters, respectively. Thus, it is urgent to reduce the environmental impact of these effluents through new integrated processes applying biorefinery and circular economy concepts to produce energy or new products. This review provides the characteristics of some of the most important agro-industrial wastes, including their physicochemical composition, worldwide average production, and possible environmental impacts. In addition, some alternatives for reusing these materials are addressed, focusing mainly on energy savings and the possibilities of generating value-added products. Finally, this review considers recent research and technological innovations and perspectives for the future.

Global cocoa fermentation microbiome: revealing new taxa and microbial functions by next generation sequencing technologies.

This review provides an overview of the application of next-generation sequencing (NGS) technologies for microbiome analysis of cocoa beans fermentation. The cocoa-producing regions where NGS has been applied include Brazil, Ghana, Ivory Coast, Cameroon, Nicaragua, and Colombia. The data collected were processed by principal component analysis (PCA) and Venn diagrams to perform a multivariate association between microbial diversity and cocoa-producing regions. NGS studies have confirmed the dominance of three major microbial groups revealed by culture-dependent approaches, i.e., lactic acid bacteria, acetic acid bacteria, and yeasts. However, a more complex microbial diversity has been revealed, comprising sub-dominant populations, late-growing species, and uncultivable microorganisms. A total of 99 microbial genera and species were for the first time reported in cocoa beans fermentation, such as Brevibacillus sp., Halomonas meridiana, Methylobacterium sp., Novosphingobium sp., and Paenibacillus pabuli. PCA and Venn diagrams showed that species composition is rarely fixed and often experiences fluctuations of varying degrees and at varying frequencies between different cocoa-producing regions. Understanding these differences will provide further directions for exploring the functional and metabolic activity of rare and abundant taxa, as well as their use as starter cultures to obtain high-quality cocoa beans.

In vitro cytotoxic effect of a chitin-like polysaccharide produced by Mortierella alpina on adrenocortical carcinoma cells H295R, and its use as mitotane adjuvant.

This study presents an in vitro evaluation of the antitumor potential of a chitin-like exopolysaccharide (EPS, produced by Mortierella alpina) on Adrenocortical carcinoma cells (ACC) compared to mitotane, a commercial drug commonly used in ACC treatment, and known for its side effects. Techniques of cellular viability determination such as MTT and fluorescence were used to measure the cytotoxic effects of the EPS and mitotane in tumoral cells (H295R) and non-tumoral cells (VERO), observing high cytotoxicity of mitotane and a 10% superior pro-apoptotic effect of the EPS compared to mitotane (p < 0.05). The cytotoxic effect of the EPS was similar to the effect of 50 µM mitotane on tumoral cells (p < 0.05). A decrement of the lysosomal volume was also noted in tumoral cells treated with the EPS. To enhance the antitumor effect, a combination of mitotane at a lower dosage and the EPS (as adjuvant) was also tested, showing a slight improvement of the cytotoxicity effect on tumoral cells. Therefore, the results indicate a cytotoxic effect of the EPS produced by Mortierella alpina on adrenocortical carcinoma, and a possible application in biomedical formulations or additional treatments.

Rice vinasse treatment by immobilized Synechococcus pevalekii and its effect on Dunaliella salina cultivation.

The development of new strategies in microalgal studies represents an outstanding opportunity to mitigate environmental problems coupled with biomass production at a reduced cost. Here we present a combined bioprocess for the treatment of rice vinasse using immobilized cyanobacteria Synechococcus pevalekii in alginate beads followed by the use of the treated vinasse as a culture medium for Dunaliella salina biomass production. Cyanobacterial-alginate beads showed a chlorophyll a production of 0.68 × 10-3 mg bead-1 and a total carotenoid production of 0.64 × 10-3 mg bead-1. The first step showed a decrease in nitrate (91%), total solids (29%), and ions. Addition of treated vinasse into D. salina cultivation resulted in a significant increase in cell replication of about 175% (optimized cultivation). The use of natural seawater drastically reduced the medium cost to US$4.75 per m3 and the addition of treated vinasse has the potential to reduce it even more (up to 69%). This study not only provides an insight on the use of cyanobacteria for rice vinasse treatment but also demonstrates a promising lower-cost medium for marine microalgal biomass production with biotechnological purposes.

Current developments and challenges of green technologies for the valorization of liquid, solid, and gaseous wastes from sugarcane ethanol production.

The sugarcane industry is one of the largest in the world and processes huge volumes of biomass, especially for ethanol and sugar production. These processes also generate several environmentally harmful solid, liquid, and gaseous wastes. Part of these wastes is reused, but with low-added value technologies, while a large unused fraction continues to impact the environment. In this review, the classic waste reuse routes are outlined, and promising green and circular technologies that can positively impact this sector are discussed. To remain competitive and reduce its environmental impact, the sugarcane industry must embrace technologies for bagasse fractionation and pyrolysis, microalgae cultivation for both CO2 recovery and vinasse treatment, CO2 chemical fixation, energy generation through the anaerobic digestion of vinasse, and genetically improved fermentation yeast strains. Considering the technological maturity, the anaerobic digestion of vinasse emerges as an important solution in the short term. However, the greatest environmental opportunity is to use the pure CO2 from fermentation. The other opportunities still require continued research to reach technological maturity. Intensifying the processes, the exploration of driving-change technologies, and the integration of wastes through biorefinery processes can lead to a more sustainable sugarcane processing industry.

Citric acid bioproduction and downstream processing: Status, opportunities, and challenges.

Citric acid (CA) has been widely used in different industrial sectors, being produced through fermentation of low-cost feedstock. The development of downstream processes, easier to operate, environmentally friendly, and more economic than precipitation, is certainly a challenge in CA bioproduction. Large volumes of by-products generated in precipitation require treatment before disposal. Adsorption, extraction, and membrane separation have been shown to have a lower environmental impact than precipitation, but the technological maturity of these methods is still limited. However, reactive extraction and adsorption have great potential for industrial applications. This review shows that there is still much to be explored, both about the factors that are intrinsic to the techniques, but also in their combination for new processes' development. This review reports the most recent advances on CA bioproduction, with significant information about recovery and purification methods involving this highly industrially demanded organic acid.

Hydrogen production by dark fermentation using a new low-cost culture medium composed of corn steep liquor and cassava processing water: Process optimization and scale-up.

The use of effluents for hydrogen production through dark fermentation is promising because it results in the generation of value-added products and reduction of the effluent's organic load. A low-cost medium using agroindustrial effluents, corn steep liquor (CSL) and cassava processing wastewater (CPW) was evaluated for hydrogen production with microbial consortia (Vir and Gal). Four variables were evaluated for their impact on biohydrogen production through a Plackett Burman design. Subsequently, the significant variables were optimized using a central composite design, resulting in two mathematical models with regression coefficients R2 > 0.92. The maximum yields were validated and resulted in 107 and 83.1 mL of biohydrogen/g COD removed for Vir and Gal, respectively. The lower medium cost for biohydrogen production was 81.5 USD/m3, approximately 80% more economical than some supplemented media. Finally, the scale-up of the biohydrogen production by consortia to 5L resulted in an increase of more than 40%.

Production, characterization, and biological activity of a chitin-like EPS produced by Mortierella alpina under submerged fermentation.

The production of a chitin-like exopolysaccharide (EPS) was optimized through experimental design methods, evaluating the influence of urea, phosphate, and glucose. Under optimized conditions, up to 1.51 g/L was produced and its physicochemical characteristics were evaluated by chromatography, NMR, and FTIR spectroscopy, and rheological techniques. The results showed a homogeneous EPS (Mw 4.9 × 105 g mol-1) composed of chitin, linear polymer of ß-(1→4)-linked N-acetyl-d-glucosamine residues. The acetylation degree as determined by 13C CP-MAS NMR spectroscopy was over 90 %. The EPS biological activities, such as antioxidant effect and antitumor properties, were evaluated. To the best of our knowledge, this is the first study on the production of a new alternative of extracellular chitin-like polysaccharide with promising bioactive properties from the filamentous fungus M. alpina.

Effects of different culture media on physiological features and laboratory scale production cost of Dunaliella salina.

Microalgal cultivation system depends on optimal parameters obtained from laboratory conditions to overcome high-value compounds production and decrease cost. In this study, the laboratory-scale cultivation of Dunaliella salina was performed to explore the cost and biochemical effects on biomass cultivated using F/2, Conway, and Johnson media. D. salina cultivation was monitored by cell counting, dry biomass measurements and biochemical analyses. Photosynthetic pigment profiles were identified and quantified through high-performance liquid chromatography (HPLC) whereas economic evaluation was based on media cost. Cellular growth parameters were significantly improved by Conway medium, whereas maximum accumulation of pigments, especially violaxanthin (0.855 mg g-1) and chlorophyll a (14.255 mg g-1) were observed when Johnson medium was used. Conway-biomass showed 43 % of total lipid content. This value represents 1.5 and 1.4 times higher than lipid content found in Johnson- and F/2-biomass, respectively. Furthermore, media cost presented a variation of US$1.17-49.62 for each 103 L of media mainly due to NaNO3, KNO3, and cyanocobalamin supplementation. Thus, biomass production showed a cost variation of US$4.64-301.61 per kg on a dry weight basis. These outcomes emphasize the suitability of laboratory parameters and cost comparison among biomass produced by different media.

Biological hydrogen production from palm oil mill effluent (POME) by anaerobic consortia and Clostridium beijerinckii.

Palm oil mill effluent (POME) was tested as a substrate to produce hydrogen by dark fermentation. Two microbial consortia and a pure culture of Clostridium beijerinckii (ATCC 8260) were cultured anaerobically in raw, diluted and hydrolyzed POME to compare biohydrogen production yields in all three media. Experiments were done in 15 mL Hungate tubes containing 5 mL of medium and 1 mL of inoculum. When Clostridium beijerinckii was cultivated at 30 °C in the hydrolyzed POME (P003), containing 7.5 g/L of sucrose, during 8 days of fermentation and 20 % of the inoculum, the maximum biohydrogen production yield was 4.62 LH2/Lmed. Consortium C3 also showed the best production in hydrolyzed POME while consortium C6 achieved its maximum production in raw POME. This effluent is a potential substrate for biohydrogen production.