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Education about climate change faces an evolution of the knowledge, and universities should respond with innovative learning processes. As facilitators can adapt to these changes, they will be able to improve learning experiences for students. In this work, learning experiences about climate change were evaluated in undergraduate students without engineering background, as function of the size of the group, duration of the course, gamification activities and technology and virtual tools experiences. The implementation of these activities in the intensive 5-week course focused on climate change education has revealed valuable insights into student motivation, attitude, knowledge acquisition, and engagement. Notably, students' trust in information sources about climate change exhibited variations, with global organizations garnering higher confidence compared to local and personal sources. In a 15-week course exposed to virtual tools (e.g. escape room), the diagnostic test highlighted a 53% understanding level, particularly challenging in numeric aspects. However, the escape room significantly improved results in the final exam, demonstrating a 93% correctness rate, emphasizing the effectiveness of the activities in reinforcing key climate change concepts. On the other hand, the emergence of climate change-themed escape room as an engagement tool demonstrated its potential in enhancing knowledge acquisition and cooperative learning. In addition, Escape room offered an immersive environment that encourages active participation, enabling students to grasp complex climate concepts and solutions more effectively. The study underscores that climate education should go beyond facts, emphasizing universities' crucial role in nurturing the "climate change generation" with the knowledge and motivation for meaningful contributions to climate action and policy formulation. [ABSTRACT FROM AUTHOR]

Nejayote and swine wastewater are highly pollutant effluents and a source of organic matter load that sometimes released into water bodies (rivers or lakes), soils or public sewer system, with or without partial treatments. Nejayote is a wastewater product of alkaline cooking of maize, whereas, swine wastewater results from the primary production of pigs for the meat market. Owing to the presence of environmentally related pollutants, both sources are considered the major cause of pollution and thus require urgent action. Herein, we report a synergistic approach to effectively use and/or treat Nejayote and swine wastewater as a cost-effective culture medium for microalgae growth, which ultimately induces the removal of polluting agents. In this study, the strains Arthrospira maxima and Chlorella vulgaris were grown using different dilutions of Nejayote and swine wastewater. Both wastewaters were used as the only source of macronutrients and trace elements for growth. For A. maxima , the treatment of 10% nejayote and 90% of water (T3) resulted in a cell growth of 32 × 104 cell/mL at 12 days (μ max = 0.27/d). While, a mixture of 25% swine wastewater, 25% nejayote and 50% water (T2) produced 32 × 104 cell/mL at 18 days (μ max = 0.16/d). A significant reduction was also noted as 92% from 138 mg/L of TN, 75% from 77 mg/L of TP, and 96% from 8903 mg/L of COD, among different treatments. For C. vulgaris , the treatment of 10% swine wastewater and 90% water (T1) gave a cell growth of 128 × 106 cell/mL (μ max = 0.57/d) followed by T3 yielded 62 × 106 cell/mL (μ max = 0.70/d) and T2 yielded 48 × 106 cell/mL (μ max = 0.54/d). Up to 91% reduction from 138 mg/L of TN, 85% from 19 mg/L of TP and 96% from 4870 mg/L of COD was also recorded. These results show that microalgae can be used to treat these types of wastewater while at the same time using them as a culture media for microalgae. The resultant biomass can additionally be used for getting other sub-products of commercial interest. Unlabelled Image • The mix of nejayote and swine wastewater allows the microalgae cell growth. • Kinetics of cell growth adjusted at logit mathematic model. • Microalgae were able to grow in nejayote-based culture media. • Microalgae removed TN, TP and COD in nejayote and swine wastewater. [ABSTRACT FROM AUTHOR]

Abstract Owing to the controlled or uncontrolled industrial wastewater disposal, pharmaceutical-based hazardous emerging contaminants (ECs) can be found in the environment all over the world. With ever-increasing socioeconomic aspects and environmental awareness, people are now more concerns about the widespread occurrences of hazardous and persistent contaminants, around the globe. In this context, several studies have already shown that various types of emerging and/or re-emerging contaminants, regardless the source, type and concentration, are of supreme threat to the living system of flora and fauna. Recently, algae-based bioreactors have gained special research interest as a promising way to remove pharmaceuticals-based ECs from the wastewater either partially or completely. This paper covers the progress on the removal of selected pharmaceuticals using bioreactors. In laboratory scale studies, high removal percentages have been reached for most selected pharmaceuticals, but data on full-scale bioreactors is limited. In this paper, two types of bioreactors are discussed, i.e., (1) open pond and (2) bubble column photobioreactor, which are considered sustainable and an effective alternative to remove ECs. In these bioreactors, high removal percentages (>90%) have been found for metoprolol, triclosan, and salicylic acid, moderate (50–90%) for carbamazepine and tramadol and very low (<10%) for trimethoprim and ciprofloxacin by inoculating different microalgae. This technique may open new opportunities for the treatment of wastewater and reduce the environmental pollution that can have adverse effects on the ecosystem and human health. In summary, the present review focuses on the microalgae for wastewater remediation. An effort has also been made to describe the generalities of the photobioreactor. Graphical abstract Unlabelled Image Highlights • We reviewed algal-based removal strategies for hazardous contaminants. • Open pond bioreactor and bubble column photo-bioreactor are discussed. • New opportunities for wastewater treatment and reduction are presented. [ABSTRACT FROM AUTHOR]

Inadequate management practices for solid waste and wastewater are some of the main causes of eutrophication globally, especially in regions where intensive livestock, agricultural, and industrial activities are coupled with inexistent or ineffective waste and wastewater treatment infrastructure. In this study, a methodological approach is presented to spatially assess the trophic state of large territories based on public water quality databases. The trophic state index (TSI) includes total nitrogen, total phosphorus, chlorophyll A, chemical oxygen demand, and Secchi disk depth values as water quality indicators. A geographical information system (GIS) was used to manage the spatiotemporal attributes of the water quality data, in addition to spatially displaying the results of TSI calculations. As a case study, this methodological approach was applied to determine the critical regions for mitigating eutrophication in the state of Jalisco, Mexico. Although a decreasing trend was observed for the TSI values over time for most subbasins (2012–2019), a tendency for extreme hypereutrophication was observed in some regions, such as the Guadalajara metropolitan area and the Altos region, which are of high economic relevance at the state level. A correlation analysis was performed between the TSI parameters and rainfall measurements for all subbasins under analysis, which suggested a tendency for nutrient wash-off during the rainy seasons for most subbasins; however, further research is needed to quantify the real impacts of rainfall by including other variables such as elevation and slope. The relationships between the water quality indicators and land cover were also explored. The GIS methodology proposed in this study can be used to spatially assess the trophic state of large regions over time, taking advantage of available water quality databases. This will enable the efficient development and implementation of public policies to assess and mitigate the eutrophication of water sources, as well as the efficient allocation of resources for critical regions. Further studies should focus on applying integrated approaches combining on-site monitoring data, remote sensing data, and machine learning algorithms to spatially evaluate the trophic state of territories. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation (UVR) has detrimental effects on human health. It induces oxidative stress, deregulates signaling mechanisms, and produces DNA mutations, factors that ultimately can lead to the development of skin cancer. Therefore, reducing exposure to UVR is of major importance. Among available measures to diminish exposure is the use of sunscreens. However, recent studies indicate that several of the currently used filters have adverse effects on marine ecosystems and human health. This situation leads to the search for new photoprotective compounds that, apart from offering protection, are environmentally friendly. The answer may lie in the same marine ecosystems since molecules such as mycosporine-like amino acids (MAAs) and scytonemin can serve as the defense system of some marine organisms against UVR. This review will discuss the harmful effects of UVR and the mechanisms that microalgae have developed to cope with it. Then it will focus on the biological distribution, characteristics, extraction, and purification methods of MAAs and scytonemin molecules to finally assess its potential as new filters for sunscreen formulation. Unlabelled Image • Ultraviolet radiation affect all living organisms on earth. • Currently used sunscreens have detrimental effects on marine ecosystems. • MAAs and scytonemin have the potential to be used as novel natural sunscreens. • Further research is needed to achieve industrial production of ecological sunscreens. [ABSTRACT FROM AUTHOR]

Lignocellulosic material has drawn significant attention among the scientific community due to its year-round availability as a renewable resource for industrial consumption. Being an economic substrate alternative, various industries are reevaluating processes to incorporate derived compounds from these materials. Varieties of fungi and bacteria have the ability to depolymerize lignocellulosic biomass by synthesizing degrading enzymes. Owing to catalytic activity stability and high yields of conversion, lignocellulolytic enzymes derived from fungi currently have a high spectrum of industrial applications. Moreover, these materials are cost effective, eco-friendly and nontoxic while having a low energy input. Techno-economic analysis for current enzyme production technologies indicates that synthetic production is not commercially viable. Instead, the economic projection of the use of naturally-produced ligninolytic enzymes is promising. This approach may improve the economic feasibility of the process by lowering substrate expenses and increasing lignocellulosic by-product's added value. The present review will discuss the classification and enzymatic degradation pathways of lignocellulolytic biomass as well as the potential and current industrial applications of the involved fungal enzymes. Unlabelled Image • Agro-industrial waste degraded by basidiomycete produce a variety of new products • New enzymes from Mexico's native fungi considerably stimulates the in situ production • Abundant biodiversity of Mexican fungi produce a variety of catalytic enzymes [ABSTRACT FROM AUTHOR]

Several factors have the potential to influence microalgae growth. In the present study, nitrogen concentration and light intensity were evaluated in order to obtain high biomass production and high phycoerythrin accumulation from Porphyridium purpureum . The range of nitrogen concentrations evaluated in the culture medium was 0.075-0.450 g L -1 and light intensities ranged between 30 and 100 μmol m -2 s -1 . Surprisingly, low nitrogen concentration and high light intensity resulted in high biomass yield and phycoerythrin accumulation. Thus, the best biomass productivity (0.386 g L -1 d -1 ) and biomass yield (5.403 g L -1 ) were achieved with NaNO 3 at 0.075 g L -1 and 100 μmol m -2 s -1 . In addition, phycoerythrin production was improved to obtain a concentration of 14.66 mg L -1 (2.71 mg g -1 of phycoerythrin over dry weight). The results of the present study indicate that it is possible to significantly improve biomass and pigment production in Porphyridium purpureum by limiting nitrogen concentration and light intensity.

Background: Microalgae produce metabolites with notable potentialities to act as reducing and capping agents for the synthesis of silver nanoparticles (AgNPs) in a process widely recognized as an eco-friendly and cheaper alternative for the generation of nanoparticles (NPs)., Methods: In the present work, AgNPs were synthesized using live Botryococcus braunii cultures. Two biosynthesis routes were explored: (1) intracellular and (2) extracellular at pH levels of 6-9 using 1-5 mM silver nitrate concentrations., Results: The generation of NPs was confirmed via ultraviolet-visible spectroscopy. The morphological characteristics were observed using scanning electron microscopy which revealed that the newly developed AgNPs were mostly spherical in sizes starting from 168 nm. The characteristic peaks in a typical Fourier transform infrared spectroscopy suggested that the exopolysaccharides were the possible reducing and capping agents. The antimicrobial spectrum of the newly developed AgNPs was tested against bacterial strains, both Gram-negative, Gram-positive, and yeast, ie, Escherichia coli (American Type Culture Collection [ATCC] 25922), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), and the yeast Candida albicans (ATCC 10231), respectively. The antimicrobial activity tests showed a stronger inhibition against Gram-negative bacteria. Statistically, the NPs biosynthesized at pH values of 6 and 8 displayed a higher antimicrobial activity., Conclusion: Our findings showed that B. braunii is capable of generating AgNPs with antimicrobial potential., Competing Interests: Disclosure The authors report no conflicts of interest in this work.