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Efforts are intensifying to identify new biofuel sources in response to the pressing need to mitigate environmental pollutants, such as greenhouse gases, which are key contributors to global warming and various worldwide calamities. Algae and microalgae present themselves as excellent alternatives for solid-gaseous fuel production, given their renewable nature and non-polluting characteristics. However, making biomass production from these organisms economically feasible remains a challenge. This article collates various studies on the use of lignocellulosic waste, transforming it from environmental waste to valuable organic supplements for algae and microalgae cultivation. The focus is on enhancing biomass production and the metabolites derived from these biomasses.

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The current burden associated to multidrug resistance, and the emerging superbugs, result in a decreased and even loss of antibiotic efficacy, which poses significant challenges in the treatment of infectious diseases. This situation has created a high demand for the discovery of novel antibiotics that are both effective and safe. However, while antibiotics play a crucial role in preventing and treating diseases, they are also associated with adverse effects. The emergence of multidrug-resistant and the extensive appearance of drug-resistant microorganisms, has become one of the major hurdles in healthcare. Addressing this problem will require the development of at least 20 new antibiotics by 2060. However, the process of designing new antibiotics is time-consuming. To overcome the spread of drug-resistant microbes and infections, constant evaluation of innovative methods and new molecules is essential. Research is actively exploring alternative strategies, such as combination therapies, new drug delivery systems, and the repurposing of existing drugs. In addition, advancements in genomic and proteomic technologies are aiding in the identification of potential new drug targets and the discovery of new antibiotic compounds. In this review, we explore new sources of natural antibiotics from plants, algae other sources, and propose innovative bioinspired delivery systems for their use as an approach to promoting responsible antibiotic use and mitigate the spread of drug-resistant microbes and infections.

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The heightened interest in healthy dietary practices and the preference for fresh, minimally processed foods with reduced additives have witnessed a significant surge among consumers. Within this context, bioactive compounds have garnered attention as potent agents offering beneficial biological effects when integrated into food formulations. Nevertheless, the efficacy of these bioactive compounds in product development encounters numerous challenges during various processing and storage stages due to their inherent instability. Addressing these limitations necessitates exploring novel technological approaches tailored explicitly to the application of bioactive compounds in food production. These approaches should not only focus on preserving the bioactive compounds within food matrices but also on retaining the sensory attributes (color, taste, and aroma) of the final food products. The impact of microalgae and their bioactive compounds on human health and well-being has been extensively reported in the literature. However, there is still a gap regarding the processing and stability of microalgal bioactive compounds to improve their application in the food industry. The main goal of the present work is to point out how to overcome technological challenges in enhancing the stability of bioactive compounds from microalgae for optimal food applications.

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Mazzaella, a genus with no genomic resources available, has extensive distribution in the cold waters of the Pacific, where they represent ecologically and economically important species. In this study, we aimed to sequence, assemble, and annotate the complete mitochondrial and chloroplast genomes from two Mazzaella spp. and characterize the intraspecific variation among them. We report for the first time seven whole organellar genomes (mitochondria: OR915856, OR947465, OR947466, OR947467, OR947468, OR947469, OR947470; chloroplast: OR881974, OR909680, OR909681, OR909682, OR909683, OR909684, OR909685) obtained through high-throughput sequencing for six M. laminarioides sampled from three Chilean regions and one M. membranacea. Sequenced Mazzaella mitogenomes have identical gene number, gene order, and genome structure. The same results were observed for assembled plastomes. A total of 52 genes were identified in mitogenomes, and a total of 235 genes were identified in plastomes. Although the M. membranacea plastome included a full-length pbsA gene, in all M. laminarioides samples, the pbsA gene was split in three open reading frames (ORFs). Within M. laminarioides, we observed important plastome lineage-specific variations, such as the pseudogenization of the two hypothetical protein-coding genes, ycf23 and ycf45. Nonsense mutations in the ycf23 and ycf45 genes were only detected in the northern lineage. These results are consistent with phylogenetic reconstructions and divergence time estimation using concatenated coding sequences that not only support the monophyly of M. laminarioides but also underscore that the three M. laminarioides lineages are in an advanced stage of divergence. These new results open the question of the existence of still undisclosed species in M. laminarioides.

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Biocrusts determine soil stability and resiliency, with a special role played by oxygenic photoautotrophic microorganisms in these communities. We evaluated temporal and geographic trends in studies focused on these microorganisms in biocrusts. Two databases were surveyed to obtain scientific articles published from 1998 to 2020 containing the terms 'biocrusts,' 'algae,' and 'cyanobacteria.' Although interest in biocrusts has increased recently, their ecological importance is still little explored. The scientific articles that mentioned a species list of cyanobacteria and/or algae revealed a very heterogeneous geographic distribution of research. Biocrusts have not been explored in many regions and knowledge in the tropics, where these communities showed high species richness, is limited. Geographic gaps were detected and more detailed studies are needed, mainly where biocrust communities are threatened by anthropogenic impacts. Aiming to address these knowledge gaps, we assembled a taxonomic list of all algae and cyanobacteria found in these articles, including information on their occurrence and ecology. This review is an updated global taxonomic survey of biocrusts, which importantly reveals their high species richness of oxygenic photoautotrophic microorganisms. We believe this database will be useful to future research by providing valuable taxonomic and biogeographic information regarding algae and cyanobacteria in biocrusts.

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BACKGROUND: The decarbonization of road transport is a precondition for achieving carbon neutrality. Battery-electric vehicle technology can make this a reality. In this bias, the objective of the article is to shed light on the ongoing debate about the potentially important role of the adoption of electric vehicles in the transport of microalgae- based products to help them advance to a cleaner life cycle. METHODS: Five routes, including unimodal and multimodal conditions, were defined to assess the carbon emissions of the transport system and, more specifically, of road transport. The headquarters of market-leading microalgae manufacturers were selected as the origin of the routes and, as the destination, regions that sustain them. RESULTS: The results reveal the supremacy of road transport of microalgae-based products using electric vehicles powered by nuclear, hydroelectric, and wind, followed by biomass and photovoltaic energy. They also show that the positive impact of wind, water, and photovoltaic energy on the climate, added to the lower battery charging costs and the greater opportunity to generate revenue from the sale of carbon credits, make their tradeoffs. CONCLUSION: The exquisite results of this study convey key messages to decision-makers and stakeholders about the role of electromobility in building a zero-carbon delivery route.

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A reclassification of Cyanidium chilense under the new genus Cavernulicola was recently proposed together with a new family (Cavernulicolaceae) and a new order (Cavernulicolales). Unfortunately, due to an error in the required citation of the basionym, the name "Cavernulicola chilensis" was invalid and cannot be accepted as the generitype of Cavernulicola. This means that Cavernulicola, Cavernulicolaceae, and Cavernulicolales are likewise invalid names under the provisions of the International Code of Nomenclature for algae, fungi, and plants (ICN, Shenzhen Code). In this contribution, each of these names is validated.

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Rhodolith beds are known worldwide to host high biodiversity to several taxa. Despite their importance, few ecological data explored the influence of rhodolith features and environmental variables on associated biodiversity, a gap that has been hampering the mapping of diversity hotspots and priority areas for conservation. In this study, we investigated large-scale spatial variations of rhodolith beds and their associated fauna, using annelid polychaetes as a biological model. We aimed to identify proxies, based on rhodolith features and environmental variables, to detect biodiversity hotspots across Southwestern Atlantic beds, laying the groundwork for mapping priority areas for conservation. With this goal, we sampled a total of 136 rhodolith nodules across seven sites with beds under distinct latitudes, depths, distances from the mainland coast of Brazil, and rhodolith densities. For each nodule sampled, we measured the volume, diameter, and mass of sediment trapped, as well as the attributes of the associated polychaetes (abundance, richness, diversity, and composition). Our results revealed a complex network of collinearities and synergisms between the rhodolith features and the majority of the polychaetes attributes (i.e., abundance, diversity, and composition). Polychaete richness, in contrast, can be explained by the combination of two proxies: (1) rhodolith nodule diameter and (2) distance of the rhodolith bed from the mainland coast. Nearshore rhodolith beds and larger nodules were associated with higher values of richness. Additionally, rhodoliths with a hollow morphology were also associated with higher values of polychaete richness. These results suggest that nearshore rhodolith beds with large and hollow nodules could be priority areas for conservation. However, further multi-taxa studies using our framework are still needed to explore other regions and scales, delineating more comprehensive proxies for predicting ecological patterns of the rhodoliths associated fauna and to identify priorities for conservation across Southwestern Atlantic beds.

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Benthic dinoflagellates produce potent toxins that may negatively affect humans and the marine biota. Understanding the factors that stimulate their growth is important for management strategies and to reduce their potential negative impacts. Laboratory cultures have been extensively used to study microalgae physiology and characterize life cycles, nutrition, growth rates, among other processes. A systematic review of the literature on the growth parameters of the benthic dinoflagellates Ostreopsis cf. ovata, Prorocentrum lima species complex and Coolia malayensis obtained in laboratory cultures of strains isolated from all over the world was performed. The effects of temperature, light intensity, photoperiod, salinity and culture media on the growth rate of these species were evaluated using multiple regressions and a model selection approach, based on the Akaike Information Criteria (AIC). The potential effects of the initial culture abundance and the media volume used on the growth of the species were also assessed. Data from 50 articles (25 for O. cf. ovata, 21 for P. lima and 6 for C. malayensis), resulting in 399 growth parameter values (growth rate, doubling time and maximum yield) were compiled in a database. The genetic clades of O. cf. ovata and P. lima species complex were also noted. Growth rate was the most frequently reported growth parameter for the three species, and 127 values were retrieved for O. cf. ovata, 90 for P. lima and 56 for C. malayensis. Temperature was the factor that best explained the growth response of P. lima and C. malayensis, whereas for O. cf. ovata, temperature and salinity were equally important. Light intensity and photoperiod were included among the six best models for the studied species but presented a weaker effect on growth. Given the observed and future projected climate change, increasing ocean temperature will promote the growth of these species, likely leading to an expansion of their impacts on ecosystems and human health. The use of common garden experiments using multiple strains from different geographic domains, particularly addressing underrepresented lineages is recommended, as they will provide more balanced insight regarding the species physiological responses to environmental drivers.

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There is a growing emphasis on seeking stabilizing agents with minimal transformation, prioritizing environmentally friendly alternatives, and actively contributing to the principles of the circular economy. This research aimed to assess the stability of a novel spray-dried hydrocolloid from high Andean algae when introduced into an aqueous solution. Nostoc sphaericum freshwater algae were subject to atomization, resulting in the production of spray-dried hydrocolloid (SDH). Subsequently, suspension solutions of SDH were meticulously prepared at varying pH levels and gelling temperatures. These solutions were then stored for 20 days to facilitate a comprehensive evaluation of their stability in suspension. The assessment involved a multifaceted approach, encompassing rheological analysis, scrutiny of turbidity, sedimentation assessment, ζ-potential, and measurement of particle size. The findings from these observations revealed that SDH exhibits a dilatant behavior when in solution, signifying an increase in with higher shear rate. Furthermore, it demonstrates commendable stability when stored under ambient conditions. SDH is emerging as a potential alternative stabilizer for use in aqueous solutions due to its easy extraction and application.