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In recent years, there has been a notable surge in the development and adoption of edible algae protein-based sustainable food packaging, which presents a promising alternative to traditional materials due to its biodegradability, renewability, and minimal environmental impact. Hence, this review aims to emphasize the sources, cultivation, and downstream potential of algal protein and protein complexes. Moreover, it comprehensively examines the advancements in utilizing protein complexes for smart and active packaging applications, while also addressing the challenges that must be overcome for the widespread commercial adoption of algal proteins to meet industry 4.0. The review revealed that the diversity of algae species and their sustainable cultivation methods offers a promising alternative to traditional protein sources. Being vegan source with higher photosynthetic conversion efficiency and reduced growth cycle has permitted the proposition of algae as proteins of the future. The unique combination of techno-functional combined with bio-functional properties such as antioxidant, anti-inflammatory and antimicrobial response have captured the sustainable groups to invest considerable research and promote the innovations in algal proteins. Food packaging research has increasingly benefited by the excellent gas barrier property and superior mechanical strength of algal proteins either stand alone or in synergy with other biodegradable polymers. Advanced packaging functionality such as freshness monitoring and active preservation techniques has been explored and needs considerable characterization for commercial advancement. Overall, while algal proteins show promising downstream potential in various industries aligned with Industry 4.0 principles, their broader adoption hinges on overcoming these barriers through continued innovation and strategic development.
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Algae-derived organic matter (ADOM) is a key source of chromophoric dissolved organic matter (CDOM) in natural waters. When exposed to solar irradiation, ADOM undergoes gradual degradation and transformation. The escalating presence of microplastics (MPs) can act as a novel type of environmental photosensitizer, however its impacts on ADOM photodegradation remains largely unexplored. Thus, in this study, ADOM were extracted from four common algal species (Microcystis aeruginosa, Synechococcus sp., Chlorella pyrenoidosa and Scenedesmus obliquus) and exposed to UV irradiation with or without polystyrene (PS) MPs, namely ADOM+PS groups and ADOM groups, respectively. The results indicated that a more rapid degradation of amino acid-like substances (â¼38 % vs. â¼22 %) and more ammonia products (1.86 vs. 1.21 mg L-1) were observed in the ADOM+PS groups compared to the ADOM groups after a five-day exposure. This enhanced photodegradation might be attributed to the production of environmentally persistent free radicals and reactive species during the photoaging of PS. Furthermore, PS-derived high electron transfer belt activity of ADOM led to the production of highly aromatic and humified products. These humic-like products could potentially accelerate the degradation of amino acid-like compounds by exciting the generation of excited triplet CDOM. This study underscores the role of MPs as environmental photosensitizers in promoting ADOM degradation and ammonia generation, providing insights on the transformation of ADOM mediated by emerging pollutants and its impact on aquatic carbon and nitrogen cycles.
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Lipoxygenases (LOXs) from lower organisms have substrate flexibility and function versatility in fatty acid oxidation, but it is not clear how these LOXs acquired the ability to execute multiple functions within only one catalytic domain. This work studied a multifunctional LOX from red alga Pyropia haitanensis (PhLOX) which combined hydroperoxidelyase (HPL) and allene oxide synthase (AOS) activity in its active pocket. Molecular docking and site-directed mutagenesis revealed that Phe642 and Phe826 jointly regulated the double peroxidation of fatty acid, Gln777 and Asn575 were essential to the AOS function, and the HPL activity was improved when Asn575, Gln777, or Phe826 was replaced by leucine. Phylogenetic analysis indicated that Asn575 and Phe826 were unique amino acid sites in the separated clades clustered with PhLOX, whereas Phe642 and Gln777 were conserved in plant or animal LOXs. The N-terminal START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC (SRPBCC) domain of PhLOX was another key variable, as the absence of this domain disrupted the versatility of PhLOX. Moreover, the functions of two homologous LOXs from marine bacterium Shewanella violacea and red alga Chondrus crispus were examined. The HPL activity of PhLOX appeared to be inherited from a common ancestor, and the AOS function was likely acquired through mutations in some key residues in the active pocket. Taken together, our results suggested that some LOXs from red algae attained their versatility by amalgamating functional domains of ancestral origin and unique amino acid mutations.
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Evolução Molecular , Lipoxigenase , Filogenia , Rodófitas , Rodófitas/genética , Rodófitas/enzimologia , Lipoxigenase/genética , Lipoxigenase/metabolismo , Lipoxigenase/química , Sequência de Aminoácidos , Simulação de Acoplamento Molecular , Shewanella/enzimologia , Shewanella/genética , Mutagênese Sítio-DirigidaRESUMO
Cyanobacteria, especially Arthrospira, are valuable resources of nutrients and natural pigments with many beneficial health-related properties. This study optimized the extraction conditions of Arthrospira to achieve high phenolic contents and antioxidant activities. Under optimized extraction conditions, the bioactive compounds (phenolics and pigment components), antioxidant activities, and inhibitions of the key enzymes relevant to some non-communicable diseases were compared between Arthrospira platensis and Arthrospira maxima. Optimized extraction conditions were determined as 2 h shaking time, 50 °C extraction temperature, and 1% (w/v) solid-to-liquid ratio, giving effective phenolic and phycocyanin contents using aqueous extraction, while 80% (v/v) aqueous ethanolic extraction provided high total chlorophyll content. Most antioxidant activities were higher using 80% (v/v) aqueous ethanolic extracts. Both Arthrospira species inhibited the key enzymes involved in controlling non-communicable diseases including hyperlipidemia (lipase), diabetes (α-amylase, α-glucosidase, and dipeptidyl peptidase-IV), Alzheimer's disease (acetylcholinesterase, butyrylcholinesterase and ß-secretase), and hypertension (angiotensin-converting enzyme). High inhibitory activities were detected against ß-secretase (BACE-1), the enzyme responsible for ß-amyloid plaque formation in the brain that acts as a significant hallmark of Alzheimer's disease. Arthrospira extract and donepezil (Alzheimer's disease drug) synergistically inhibited BACE-1, suggesting the potential of Arthrospira extracts as effective BACE-1 inhibitors. Interestingly, A. maxima exhibited higher bioactive compound contents, antioxidant activities, and key enzyme inhibitions than A. platensis, indicating high potential for future food and medicinal applications.
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Antioxidantes , Fenóis , Spirulina , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Spirulina/química , Fenóis/farmacologia , Ficocianina/farmacologia , Ficocianina/metabolismo , Acetilcolinesterase/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Humanos , Lipase/metabolismo , Lipase/antagonistas & inibidores , Butirilcolinesterase/metabolismo , alfa-Glucosidases/metabolismo , Cianobactérias/química , Cianobactérias/metabolismoRESUMO
The algal-bacterial granular sludge (ABGS) system is emerging as a promising technology for future wastewater treatment. This study assessed the impact of different algae species inoculation on granulation, performance, and microbial communities within ABGS systems. The experimental setup included single-species inoculations (Chlorella sp. (R1), Scenedesmus sp. (R2), and Desmodesmus sp. (R3)) and a mixed-species inoculation strategy (R4). Results revealed that R4 achieved the fastest completed granulation process (15 days) with the largest average granule diameter (772.93 µm) and highest physical strength (2.24 ± 0.26%) in the end of the experiment. The relative abundance of extracellular polymeric substances secreting bacteria of R4 maintained high level in whole operation time. Algae assimilation capacity and the abundance of functional bacteria can also influence removal performance. In mature stage, only the average effluent total nitrogen (3.15 ± 2.87 mg/L), total phosphorus (0.37 ± 0.27 mg/L), chemical oxygen demand (25.25 ± 2.98 mg/L) concentration in R4 was lower than that of Grade I discharge standard of municipal wastewater treatment plants in China. The best inorganic carbon utilization and lipid production ability were observed in R4 and R3, respectively. The choice of inoculated algae species was identified as a key factor for bacterial community dynamics. Overall, above results demonstrated that mixed algae species inoculation can be selected as the optimal algae inoculation strategy due to its excellent granulation, performance, and acceptable carbon utilization and lipid production.
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The aim of this study was to investigate the preservative properties of alga Gelidium sp. flour when included in the glazing medium employed for the frozen storage (-18 °C) of horse mackerel (Trachurus trachurus). Different concentrations (low, medium, and high) of an aqueous extract were tested and compared to a control water-glazing condition. Quality changes (lipid oxidation and hydrolysis, fatty acid (FA) profile, and trimethylamine (TMA) formation) were determined after 3- and 6-month storage periods. A general quality loss (lipid oxidation with hydrolysis development and TMA formation) with the frozen storage period was detected in all samples. The presence of an alga flour (AF) extract in the glazing medium led to a lower (p < 0.05) TBARS and fluorescent compound formation and to higher (p < 0.05) polyene values in frozen fish. Furthermore, a preserving effect on free fatty acids was detected in AF-treated fish. On the contrary, the AF-glazing treatment did not affect (p > 0.05) the TMA formation and the total n3/total n6 FA ratio. In general, preservative effects were found to be higher in frozen fish corresponding to the medium concentration tested. Current results show the potential of Gelidium sp. flour as a natural source of preservative hydrophilic compounds for the quality enhancement of frozen horse mackerel.
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This study investigated the changes in sea ice temperature, microalgae species distribution, shape changes, and photosynthetic activity observed in the first-year ice that forms in winter in Saroma-ko Lagoon, Hokkaido, Japan. Temperatures at the bottom of the ice remained constant at -1.7°C, near the freezing point, while they varied between -6 and -1°C with diel fluctuations at the surface layer. Carefully collected algal samples showed high photosynthetic quantum yield and acclimation to the light intensities of individual ice layers; this indicates that the algal photosynthetic activity responds to dynamic changes in the ice environment, such as variations in temperature, salinity, and brine space. The algal communities consisted of more than 95% diatoms. Smaller algal cells were distributed in the upper layer of the sea ice compared to the lower layers. Chaetoceros sp., the dominant small-cell species, was evenly distributed throughout the layers. In contrast, Detonula confervacea, the dominant large-cell species, was unevenly distributed in the lower layer, with smaller colony size and cell volume in the upper layer. The shape differences observed in this species were thought to be a response to the changing environment within the first-year sea ice.
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Camada de Gelo , Microalgas , Japão , Microalgas/fisiologia , Fotossíntese , Diatomáceas/fisiologia , SalinidadeRESUMO
Algal biomass harvesting is one of key technical hurdles impeding the commercialization of algae-based biorefinery. The goal of this work is to develop an innovative technology for algae cell harvesting. Thermoresponsive polymers (TRPs) such as poly(N-isopropylacrylamide) (PNIPAM) and its derivatives were studied on their properties and potential applications for microalgae harvesting. Various PNIPAM was synthesized, and the effects of charge, molecular weight (MW), amine content, and polymer concentration on the polymer phase transition temperature, the degree of phase separation, and the harvesting of microalgae (Chlorella vulgaris) were investigated. The lower critical solution temperature (LCST) of PNIPAM decreased with the increase of polymer concentration, while the decline rate reduced under high MW. The amine content didn't significantly affect the LCST of TRPs. Approx. 92â¯% of algae cells were harvested by PNIPAM-300â¯kDa. Modified TRPs showed few benefits in enhancing algae harvesting. TRPs are a promising class of polymers for microalgae harvesting.
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CONTEXT: Inconsistent results have been reported regarding the effects of different types of algae, such as Spirulina and Chlorella, on anthropometric indices. OBJECTIVE: To conduct a meta-analysis to assess the efficacy of algae supplementation on anthropometric indices. DATA SOURCES: A comprehensive systematic search was conducted to find relevant articles published from January 1990 to January 2024. DATA EXTRACTION: Randomized controlled trials (RCTs) comparing algae supplementation with a placebo or control group were included. The risk of bias and certainty of the evidence were evaluated using the Cochrane risk-of-bias tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, respectively. The random-effects model was used to find the Weighted mean differences (WMDs) for each outcome. DATA ANALYSIS: Of 9079 distinct articles in the initial screening, 61 clinical trials were included in this meta-analysis. Algae supplementation resulted in lower body mass index (WMD, -0.27 kg/m2 (95% CI, -0.42 to -0.13); GRADE rating, low), body weight (WMD: -0.78 kg [-1.18 to -0.38]; GRADE rating, low), waist circumference (WMD, -0.68 cm [-1.27 to -0.10]; GRADE rating, very low), kilograms of body fat (WMD, -0.65 kg [-1.13 to -0.17]; GRADE rating, low), and body fat percentage (WMD, -0.9% [-1.62 to -0.17]; GRADE rating, very low) compared with placebo or controls. Nevertheless, the statistically significant effects of algae supplementation on hip circumference (WMD, -0.20 cm [-0.73 to 0.32]; GRADE rating, moderate), waist to hip ratio (WMD, -0.01 [-0.01 to 0.00]; GRADE rating, moderate), and lean body mass (WMD, -0.30 kg [-0.62 to 0.02]; GRADE rating, moderate) were not observed. CONCLUSIONS: Overall, the findings of this meta-analysis indicate supplementation with algae may exert beneficial effects on anthropometric indices. However, due to between-studies heterogeneity and very low to low levels of GRADE for significant outcomes, the results should be interpreted with caution. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42024522923.
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The Vibrio bacteria known to cause infections to humans and wildlife have been largely overlooked in coastal environments affected by beach wrack accumulations from seaweed or seagrasses. This study presents findings on the presence and distribution of potentially pathogenic Vibrio species on coastal beaches that are used for recreation and are affected by red-algae-dominated wrack. Using species-specific primers and 16S rRNA gene amplicon sequencing, we identified V. vulnificus, V. cholerae (non-toxigenic), and V. alginolyticus, along with 14 operational taxonomic units (OTUs) belonging to the Vibrio genus in such an environment. V. vulnificus and V. cholerae were most frequently found in water at wrack accumulation sites and within the wrack itself compared to sites without wrack. Several OTUs were exclusive to wrack accumulation sites. For the abundance and presence of V. vulnificus and the presence of V. cholerae, the most important factors in the water were the proportion of V. fucoides in the wrack, chl-a, and CDOM. Specific Vibrio OTUs correlated with salinity, water temperature, cryptophyte, and blue-green algae concentrations. To better understand the role of wrack accumulations in Vibrio abundance and community composition, future research should include different degradation stages of wrack, evaluate the link with nutrient release, and investigate microbial food-web interactions within such ecosystems, focusing on potentially pathogenic Vibrio species that could be harmful both for humans and wildlife.
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The current global trend in the nutrition, epidemiologic and demographic transitions collectively alarms the need to pursue a sustainable protein diet that respects ecosystem and biodiversity from alternative sources, such as algae, fungi and edible insects. Then, changing the nutrition reality is extremely important to impede the global syndemic of obesity, undernutrition and climate change. This review aims to synthesize the published literature on the potential roles of alternative proteins and their derived bioactive peptides in preventive and clinical nutrition, identify research gaps and inform future research areas. Google Scholar and PubMed databases from their inception up to 30 June 2024 were searched using keywords to access pertinent articles published in English language for the review. Overall, proteins derived from algae, fungi, and edible insects are high-quality proteins as animal sources and demonstrate significant potential as a sustainable source of bioactive peptides, which are metabolically potent and have negligible adverse effects. They show promise to prevent and treat diseases associated with oxidative stress, obesity, diabetes, cancer, cardiovascular disease (especially hypertension), and neurodegenerative diseases. Given the abundance of algae, fungi and insect peptides performed in vitro or in vivo animals, further clinical studies are needed to fully establish their safety, efficacy and practical application in preventive and clinical nutrition. Additionally, social and behavioral change communication strategies would be important to increase health awareness of nutritional benefits and promote consumer acceptance of alternative protein sources.
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The prevalence of overweight and obesity is increasing worldwide. Common comorbidities related to obesity, significantly polygenic disorders, cardiovascular disease, and heart conditions affect social and monetary systems. Over the past decade, research in drug discovery and development has opened new paths for alternative and conventional medicine. With a deeper comprehension of its underlying mechanisms, obesity is now recognized more as a chronic condition rather than merely a result of lifestyle choices. Nonetheless, addressing it solely through lifestyle changes is challenging due to the intricate nature of energy regulation dysfunction. The Federal Drug Administration (FDA) has approved six medications for the management of overweight and obesity. Seaweed are plants and algae that grow in oceans, rivers, and lakes. Studies have shown that seaweed has therapeutic potential in the management of body weight and obesity. Seaweed compounds such as carotenoids, xanthophyll, astaxanthin, fucoidans, and fucoxanthin have been demonstrated as potential bioactive components in the treatment of obesity. The abundance of natural seaweed bioactive compounds has been explored for their therapeutic potential for treating obesity worldwide. Keeping this view, this review covered the latest developments in the discovery of varied anti-obese seaweed and its bioactive components for the management of obesity.
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Terapias Complementares , Obesidade , Alga Marinha , Humanos , Obesidade/tratamento farmacológico , Fármacos Antiobesidade/uso terapêutico , Xantofilas/uso terapêutico , AnimaisRESUMO
Seaweed polysaccharides are versatile both in their functions in seaweed physiology and in their practical applications in society. However, their content and quality vary greatly. This review discusses the main factors that influence the yield and quality of polysaccharides, specifically carrageenans and agars (sulfated galactans) found in red algae species (Rhodophyta). In addition, its historical, current, and emerging applications are also discussed. Carrageenan has been influenced mainly by photosynthetically active radiation (PAR) and nitrogen, while its relationship with temperature has not yet been replicated by recent studies. Agar's seasonal trend has also been found to be more ambiguous than stated before, with light, temperature, nutrients, and pH being influencing factors. In this review, it is also shown that, depending on the compound type, seaweed polysaccharides are influenced by very different key factors, which can be crucial in seaweed aquaculture to promote a high yield and quality of polysaccharides. Additionally, factors like the extraction method and storage of polysaccharides also influence the yield and quality of these compounds. This review also highlights the drawbacks and inadequacy inherent from the conventional (or current) extraction technology approaches.
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Carragenina , Rodófitas , Alga Marinha , Rodófitas/química , Alga Marinha/química , Carragenina/química , Polissacarídeos/química , Humanos , Animais , Ágar/química , AquiculturaRESUMO
Cognitive impairments are frequently reported after ischemic strokes. Novel and effective treatments are required. This study aimed to develop a functional ingredient obtained from marine algae and to determine the effect of the extract on antioxidative stress, as well as neuroprotective effects, in a rat model of MCAO-induced ischemic stroke. Among the selected marine algal extracts, Sargassum polycystum displayed the highest total phenolic content and antioxidative potential, and was subsequently used to evaluate cognitive function in rat models of ischemic stroke. The S. polycystum extract, administered at doses of 100, 300, and 500 mg/kg BW, significantly improved cognitive function by enhancing cognitive performance in the Morris water maze and novel object recognition tests. Biochemical changes revealed that providing S. polycystum increased the activities of SOD, CAT, and GSH-Px by 52.48%, 50.77%, and 66.20%, respectively, and decreased the concentrations of MDA by 51.58% and S100B by 36.64% compared to the vehicle group. These findings suggest that S. polycystum extract may mitigate cognitive impairment in ischemic stroke by reducing oxidative stress and inhibiting S100B expression, thus highlighting its potential as a functional ingredient for drugs and nutraceuticals aimed at neuroprotection.
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Antioxidantes , Modelos Animais de Doenças , AVC Isquêmico , Fármacos Neuroprotetores , Estresse Oxidativo , Fenóis , Subunidade beta da Proteína Ligante de Cálcio S100 , Animais , Ratos , Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Masculino , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , AVC Isquêmico/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/isolamento & purificação , Fenóis/farmacologia , Fenóis/isolamento & purificação , Cognição/efeitos dos fármacos , Ratos Sprague-Dawley , Phaeophyceae/química , Sargassum/química , Disfunção Cognitiva/tratamento farmacológicoRESUMO
This literature review investigated the anti-inflammatory properties of brown algae, emphasizing their potential for dermatological applications. Due to the limitations and side effects associated with corticosteroids and immunomodulators, interest has been growing in harnessing therapeutic qualities from natural products as alternatives to traditional treatments for skin inflammation. This review explored the bioactive compounds in brown algae, specifically looking into two bioactive compounds, namely, fucoidans and phlorotannins, which are widely known to exhibit anti-inflammatory properties. This review synthesized the findings from various studies, highlighting how these compounds can mitigate inflammation by mechanisms such as reducing oxidative stress, inhibiting protein denaturation, modulating immune responses, and targeting inflammatory pathways, particularly in conditions like atopic dermatitis. The findings revealed species-specific variations influenced by the molecular weight and sulphate content. Challenges related to skin permeability were addressed, highlighting the potential of nanoformulations and penetration enhancers to improve delivery. While the in vivo results using animal models provided positive results, further clinical trials are necessary to confirm these outcomes in humans. This review concludes that brown algae hold substantial promise for developing new dermatological treatments and encourages further research to optimize extraction methods, understand the molecular mechanisms, and address practical challenges such as sustainability and regulatory compliance. This review contributes to the growing body of evidence supporting the integration of marine-derived compounds into therapeutic applications for inflammatory skin diseases.
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Anti-Inflamatórios , Phaeophyceae , Phaeophyceae/química , Anti-Inflamatórios/farmacologia , Humanos , Animais , Pele/efeitos dos fármacos , Pele/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Taninos/farmacologia , Inflamação/tratamento farmacológicoRESUMO
In this research the possibility of using a photosynthetic microbial desalination cell (PhMDC) is investigated for desalination of power plant salty wastewater (PPSWW), along with power generation and organic load removal. The PhMDC was operated with anaerobic sludge in the anode chamber, microalgae in the cathode chamber, and different conductivities of PPSWW (10, 20, 40, and 55 mS cm-1) in the desalination chamber under different illumination modes (continuous light mode and light/dark mode). The highest power density (285.5 mW m-2), desalination efficiency (60.9%), and COD removal (74.8%) was achieved at conductivity of 55 mS cm-1 under continuous light mode. The highest algal growth (900 mg. L-1) was also observed at this conductivity. The applied system demonstrated effective removal of different presented cations and anions in PPSWW with removal efficiencies of more than 58%. Dynamic shift of microbial community in the anode chamber showed notable increase in sulfate-reducing bacteria and some specific genera such as Desulfovibrio, Pseudomonas, Rhodobacter, Rhodopseudomonas, and Desulfuromonas due to their potential for electricity generation and adaptation to saline and acidic conditions.
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Qingcaosha Reservoir is one among the important reservoirs and drinking water sources in Shanghai. Samples were collected from the reservoir every month from 2014 to 2021 to analyze phytoplankton community structure and water environmental factors to provide a reasonable reference for urban reservoir operation management, water resource protection, and development and utilization. The results showed that 561 species of phytoplankton were identified from eight phyla in 8a, mainly diatomata, chlorophyta, and cyanophyta, accounting for 34.94%, 34.58%, and 17.65% of the total species, respectively. A total of 26 dominant species were present in four phyla, and cyanobacteria accounted for 50%. Diatoms and green algae were the dominant species, cyanobacteria was the absolute dominant species, and other phyla accounted for a low proportion in the community structure. The Qingcaosha reservoir had the tendency of transforming into a cyanobacteria-type reservoir. The major dominant genera of chlorophyta were Scenedesmus, Ankistrodesmusc, and Chlorellaceae. The dominant genera of the phylum cyanobacteria were Merismopediaceae, Microcystaceae, Aphanocapsa, and Pseudanabaenaceae. The major dominant genera of the diatoms were Cyclotella, Melosira, and Aulacoseira. The dominant genus of xanthophyta was Tribonemataceae. Phytoplankton abundance ranged from 8.391×105 to 2.115×107 cells·L-1, with an average of 6.345×106 cells·L-1. The biomass of phytoplankton varied from 0.113 to 11.903 mg·L-1, with an average of 1.538 mg·L-1. The maximum abundance occurred in summer, and the maximum biomass occurred in spring. In spatial distribution, the maximum biomass and abundance appeared in the reservoir. Redundancy analysis ï¼RDAï¼ of phytoplankton community structure and water environmental factors showed that water temperature ï¼WTï¼, dissolved oxygen ï¼DOï¼, and nutrient salts ï¼TN, TPï¼ were important environmental factors affecting phytoplankton community structure, and significant changes occurred in 2014-2017 and 2018-2021. From 2018 to 2021, cyanobacteria disappeared and cyanobacteria dominated the reservoir and even changed to cyanobacteria-type reservoirs. From 2016 to 2021, half of the dominant species were cyanobacteria, and the cyanobacteria abundance accounted for the highest proportion during this period. The reasons for the extinction of xanthophyta were speculated to be the increase in phosphorus concentration and water temperature, and the reasons for the dominant position of cyanophyta, to be the rise of water level, water temperature, and alkaline water. Reservoirs use filter-feeding fish to control algal overgrowthï¼ however, filter-feeding fish do not filter all algae and not all of their filter-feeding algae is easily digestible. In this study, it was observed that the size of digestible algae biomass in the four seasons was in the order of spring > summer > autumn > winter. RDA analysis of silver carp, bighead carp, and digestible algae showed that the biomass of digestible algae was positively correlated with that of silver carp and bighead carp in spring, autumn, and winter. These results suggest that the digestibility of algae changed the resource use efficiency of filter-feeding fish and led to changes in phytoplankton community structure. The phytoplankton community structure was directly affected by the descending effect of fish and indirectly affected by the digestibility of algae.
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Clorófitas , Cianobactérias , Diatomáceas , Fitoplâncton , Dinâmica Populacional , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/classificação , China , Cianobactérias/crescimento & desenvolvimento , Diatomáceas/crescimento & desenvolvimento , Clorófitas/crescimento & desenvolvimento , Abastecimento de Água , Monitoramento Ambiental , Estações do AnoRESUMO
BACKGROUND/OBJECTIVES: Phloroglucinol (PHL), a phenolic compound extracted from the brown alga Rosenvingea intricata, exhibits potent antioxidant and anticancer properties. This study aims to extract, purify, and characterize PHL, and further develop functionalized zinc oxide nanoparticles (ZnO NPs) loaded with PHL to enhance its therapeutic potential. METHODS: PHL was extracted using acetone and purified through Sephadex LH-20 column chromatography, yielding a highly enriched fraction (F-3). The purified compound was characterized by FTIR, HPLC, NMR, and LC-MS. ZnO NPs were synthesized, PEGylated, and conjugated with PHL, forming ZnO-PEG-PHL NPs. Their characterization included DLS, zeta potential, XRD, SEM-EDAX, and encapsulation efficiency studies. Antioxidant assays (DPPH, FRAP, ABTS, RPA) were performed and in vitro cytotoxicity on A549 lung cancer cells were determined to evaluate the therapeutic efficacy of PHL. RESULTS: The purified PHL fraction showed a high phenolic content (45.65 PHL mg/g), which was was confirmed by spectral analysis. The ZnO-PEG-PHL NPs increased in size from 32.36 nm to 46.68 nm, with their zeta potential shifting from -37.87 mV to -26.82 mV. The antioxidant activity was superior for the ZnO-PEG-PHL NPs in all assays, while the in vitro cytotoxicity tests showed an IC50 of 40 µg/mL compared to 60 µg/mL for the ZnO NPs and 70 µg/mL for PHL. Apoptotic studies revealed significant cell cycle arrest and apoptosis induction. CONCLUSIONS: The synthesized ZnO-PEG-PHL NPs demonstrated enhanced antioxidant and anticancer properties, making them promising candidates for cancer therapy and antioxidant applications.
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Algae extracts may be a promising alternative to harmful chemicals and pesticides used commercially in the cultivation of plants with higher nutritional and health-promoting values. The cultivation of barley microgreens (Hordeum vulgare L.) was facilitated by the use of aqueous extracts from Fucus vesiculosus algae, which served as a biostimulant. Seeds for experiments were produced in accordance with EU standards, certified as organic and used to grow plants in a controlled pot experiment. A qualitative analysis of the extract, which was used to irrigate the plants, was also performed in this study, as well as stimulating properties by activating the system protecting against oxidative stress. Total phenolic content (TPC), total flavonoid content (TFV) and enzymes involved in their formation such as phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO), as well as enzymes involved in the removal of reactive oxygen species such as catalase (CAT) and superoxide dismutase (SOD), were determined in the obtained microgreen samples. Antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) was also evaluated. A noticeable increase in SOD content and antioxidant activity against DPPH was observed in barley microgreen samples after extract treatment. These results suggest that the use of extracts of this beneficial alga can enhance the antioxidant activity of the barley microgreens.
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The blue algae can be used as a nitrogen agent for promoting biological coalbed methane, but its applicability and microbial mechanism in different microbial enhanced coalbed methane technologies kept unknown. This study evaluated the methanogenic efficiency of blue algae addition with a mass ratio of 10% under fermentative degradation and microbial electrolytic cell technologies, and studied the changes of coal microstructure, surface functional groups, organic components and microbiome. The results showed that the algae addition affected the micro-concave-convex structure, non-uniform distribution of micro-particles and micro-cracks of coals, and finally increased the methanogenic rate by 1.74-2.66 times. The algae addition mainly affected the coal organic components including hydroxyl structure, hydrocarbon structure, aliphatic oxygen-containing functional groups and aromatic structure, as well increased the humus acids and microbial metabolites in fermentation broth; among them, the increased metabolites showed great differences between different technologies. The algae addition mainly increased the genera belonging to phylum Bacillota (such as Bacillus and Clostridium) and methanogens (Methanosarcina and Methanoculleus). These Bacillota groups could degrade organic matter into acetate and methanol via pathways of glycolysis and benzoate degradation, which provided substrates for such methanogens. This study strengthened the effectiveness of blue algae in enhancing technologies for biological coalbed methane.