Reverse osmosis is the leading technology for desalination of brackish water and seawater, important for solving the growing problems of fresh water supply. Thermal technologies such as multi-effect distillation and multi-stage flash distillation still comprise an important portion of the world’s desalination capacity. They consume substantial amounts of energy, generally obtained from fossil fuels, due to their low efficiency. Hybridization is a strategy that seeks to reduce the weaknesses and enhance the advantages of each element that makes it up. This paper introduces a review of the most recent publications on hybridizations between reverse osmosis and thermal desalination technologies, as well as their integration with renewable energies as a requirement to decarbonize desalination processes. Different configurations provide improvements in key elements of the system to reduce energy consumption, brine production, and contamination, while improving product quality and production rate. A combination of renewable sources and use of energy and water storage systems allow for improving the reliability of hybrid systems.

A cyanobacterium containing phycobiliproteins with far-red acclimation was isolated from Pozas Rojas, Cuatro Ciénegas, México. It was named Leptolyngbya CCM 4 after phylogenetic analysis and a description of its morphological characteristics. Leptolyngbya was grown in far-red light. Sucrose-gradient analysis of the pigments revealed two different colored bands of phycobiliproteins. A band at 60% sucrose was a phycocyanin containing phycobilisome; at 35% sucrose, a new type of phycobiliprotein absorbed at 710 nm. SDS-PAGE revealed the presence of two types of core-membrane linkers. Analysis of the hydrophobic pigments extracted from the thylakoid membranes revealed Chl a, d, and f. The ratio of Chl f/a was reversibly changed from 1:12–16 under far-red light to an undetectable concentration of Chl f under white light. Cuatro Ciénegas, a place surrounded by the desert, is a new ecosystem where a cyanobacterium, which grows in farred light, was discovered.

The marine unicellular green cyanobacterium Prochlorococcus marinus MIT9313 belongs to the most abundant and photosynthetically productive genus of cyanobacteria in the oceans. This monophyletic genus use divinyl chlorophyll a (Chl a 2 ) and b (Chl b 2 ) to build the photosystems and the membrane-intrinsic Pcb-type antennae. We used the mild detergent n-dodecyl β D-maltopyranoside to solubilize the thylakoid membranes. Gel electrophoresis and sucrose gradient ultracentrifugation was then used to separate the complexes of the photosynthetic apparatus. The proteins and the pigments were identified by mass spectrometry. Protein complexes were characterized biochemically, and the distribution of Chl a 2 and Chl b 2 was determined. The photosynthetic apparatus was shown as supercomplexes formed by Photosystem II dimers with up to eight PcbB proteins; Photosystem I was present as trimers. A heterogeneous distribution of pigments was shown using sucrose gradient-enriched fractions with ratios of [Chl b 2 ]/[Chl a 2 ] of 2.16 ± 0.13, 1.86 ± 0.08, and 2.61 ± 0.07, for Photosystem I, Photosystem II, and PcbB, respectively. These ratios of Chl b/a are without precedent in organisms with oxygenic photosynthesis. Diaphorase activity was measured in the fractions of the sucrose gradient. Gel electrophoresis, immunodetection, and mass spectrometry were used to conclude that the commonly soluble protein ferredoxin-NADP+ reductase (FNR) is a membrane-anchored protein (probably associated to cytochrome b 6 f complex) in the low-light adapted Prochlorococcus marinus MIT9313.

In this paper, sediments from the Santiago River were characterized to look for an alternative source of inoculum for biogas production. A proteomic analysis of methane-processing archaea present in these sediments was carried out. The Euryarchaeota superkingdom of archaea is responsible for methane production and methane assimilation in the environment. The Santiago River is a major river in México with great pollution and exceeded recovery capacity. Its sediments could contain nutrients and the anaerobic conditions for optimal growth of Euryarchaeota consortia. Batch bioreactor experiments were performed, and a proteomic analysis was conducted with current database information. The maximum biogas production was 266 NmL·L⁻¹·g VS⁻¹, with 33.34% of methane, and for proteomics, 3206 proteins were detected from 303 species of 69 genera. Most of them are metabolically versatile members of the genera Methanosarcina and Methanosarcinales, both with 934 and 260 proteins, respectively. These results showed a diverse euryarcheotic species with high potential to methane production. Although related proteins were found and could be feeding this metabolism through the methanol and acetyl-CoA pathways, the quality obtained from the biogas suggests that this metabolism is not the main one in carbon use, possibly the sum of several conditions including growth conditions and the pollution present in these sediments

The growing global population and increasing water demand have intensified the urgency for efficient wastewater treatment strategies to address environmental pollution and water scarcity. Physicochemical treatment technologies remain among the most widely implemented solutions due to their high removal efficiency, operational simplicity, and relatively low cost. These processes effectively target a broad spectrum of contaminants—including suspended solids, heavy metals, recalcitrant organic compounds, and high salinity—through unit operations such as coagulation, flocculation, adsorption, and filtration. Nevertheless, they often generate concentrated waste streams that present significant disposal and environmental challenges. Applying these technologies within a circular economy framework enables wastewater reuse, resource recovery, and a reduced environmental impact. Circular strategies enable the recovery and reuse of water, energy, and materials, converting waste into valuable resources. Treated water can be safely reused, while by-products such as biogas and nutrients (e.g., phosphorus, nitrogen, and organic carbon) can be recovered and reintegrated into agricultural and industrial processes. Furthermore, advanced methods such as membrane separation and electrochemical treatments allow for the selective recovery of high-value metals. This review analyzes key physicochemical technologies for wastewater treatment and evaluates their integration into circular economy models, with a focus on waste valorization, resource recovery, and environmental impact reduction. By adopting circular approaches, wastewater treatment systems can enhance sustainability, improve economic performance, and contribute to achieving the global water and sanitation target.