Algal Species Research Articles

Optimal algae species inoculation strategy for algal-bacterial granular sludge: Sludge characteristics, performance and microbial community

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.

Genome-wide analysis and expression profile of the bZIP gene family in Neopyropia yezoensis

The basic leucine zipper (bZIP) family consists of conserved transcription factors which are widely present in eukaryotes and play important regulatory roles in plant growth, development, and stress responses. Neopyropia yezoensis is a red marine macroalga of significant economic importance; however, their bZIP family members and functions have not been systematically identified and analyzed. In the present study, the bZIP gene family in Ny. yezoensis was characterized by investigating gene structures, conserved motifs, phylogenetic relationships, chromosomal localizations, gene duplication events, cis-regulatory elements, and expression profiles. Twenty-three Ny. yezoensis bZIP (NyybZIP) genes were identified and sorted into 13 out of 30 groups, which were classified based on the bZIPs of Ny. yezoensis and 15 other red algae species. Phylogenetic analysis revealed that bZIP genes may have a complex evolutionary pattern in red algae. Cross-species collinearity analysis indicated that the bZIP genes in Ny. yezoensis, Neoporphyra haitanensis, and Porphyra umbilicalis are highly evolutionarily conserved. In addition, we identified four main categories of cis-elements, including development-related, light-responsive, phytohormone-responsive and stress-responsive promoter sequences in NyybZIP genes. Finally, RNA sequencing data and quantitative real-time PCR (qRT-PCR) showed that NyybZIP genes exhibited different expression patterns depending on the life stage. NyybZIP genes were also found to be involved in the nitrogen stress response. We thought that bZIP genes may be involved in Ny. yezoensis growth and development, and play a significant role in nitrogen deficiency response. Taken together, our findings provide new insights into the roles of the bZIP gene family and provide a basis for additional research into its evolutionary history and biological functions.

Antiviral effects of Sarcodia suae water extracts against vesicular stomatitis virus infection

ABSTRACT Marine algae, a rich source of bioactive substances, have long been utilized in biomedical and veterinary sciences. This study breaks new ground by assessing the antiviral therapeutic potential of water extracts from four algal species – Colaconema formosanum, Caulerpa microphysa, Gelidium amansii and Sarcodia suae – against vesicular stomatitis virus (VSV) infection. The standout among these was Sarcodia suae water extract (SSWE), which not only significantly repressed VSV replication and enhanced cell survival without cytotoxic effects, but also demonstrated its antiviral activity through interference with viral attachment, entry, RNA replication, and egress, and reduced VSV-induced autophagy in Mv1Lu cells during the late stages of infection. The EC50 of SSWE was 0.422 ± 0.14 mg ml‒1. The cytotoxicity assay confirmed the high biocompatibility of SSWE. This study identifies SSWE as a promising natural antiviral agent and elucidates its mechanisms of action, highlighting the need for further research to optimize its use in controlling VSV-related diseases.

Influence of multi-stress factors on the growth of Chlorella pyrenoidosa and Scenedesmus abundans using response surface methodology.

This study evaluated the biofuel production potential of two algal species, Chlorella pyrenoidosa and Scenedesmus abundans, under stress conditions induced by nutrient supplementation or starvation at varying light intensities. Central composite face-centered design response surface methodology (CCFD-RSM) was employed to optimize stress conditions by varying the sodium nitrate (NaNO3), potassium dihydrogen phosphate (KH2PO4), dipotassium hydrogen phosphate (K2HPO4), cultivation time, and light intensity. The study included both C. pyrenoidosa and S. abundans, which presented increased biomass yields when subjected to nutrient starvation. Under the optimized conditions, the dry biomass yield was 98.26mg/L for C. pyrenoidosa and 110mg/L for S. abundans. Lipid yields were approximately 22.47% for C. pyrenoidosa and 29.06% for S. abundans under these optimized growth conditions. The optimized parameters for maximum biomass and lipid production were identified as C. pyrenoidosa, and the optimized conditions required 0.805g/L NaNO3, 0.052g/L K2HPO4, 0.099g/L KH2PO4, 17days of culture, and 5168.39lx of light intensity. For S. abundans, the optimal conditions were 1.065g/L NaNO3, 0.071g/L K2HPO4, 0.058g/L KH2PO4, 22days of cultivation, and 2897lx of light intensity. Overall, both C. pyrenoidosa and S. abundans have emerged as promising candidates for sustainable biodiesel production, highlighting their potential under stress conditions induced by nutrient modulation and variable light intensities.

Seaweed-derived etherified carboxymethyl cellulose for sustainable tissue engineering

Biodegradability, biocompatibility, abundant supply from renewable sources, and affordability are the outstanding properties of cellulose that have prompted substantial studies into its potential in biomedical applications. Beyond terrestrial sources of cellulose, seaweeds have attracted much attention as a potential source of cellulose because they are widely available. Cellulose and its byproducts may be extracted from various macroalgae species, including red, green, and brown algae. The extracted cellulose's qualities vary depending on the algae species, age, and extraction process utilized. Cellulose's characteristics are enhanced through chemical modifications, specifically etherification and esterification, which substitute functional groups for hydroxyl groups, yielding a range of products, including cellulose acetate (CA), cellulose nitrate, cellulose sulfate, methylcellulose, and carboxymethyl cellulose (CMC). The ability to modify CMC characteristics for particular applications is explored through techniques including grafting processes mixing, and cross-linking with other polymers. Moreover, tissue engineering is given significant consideration in the growing use of CMC and its altered forms in biological applications. These alterations allow for the production of scaffolds that promote tissue regeneration and cell proliferation, enabling CMC-based scaffolds for various tissue engineering uses. This review provides a comprehensive overview of CMC's properties, modifications, and potential in tissue engineering.

Genomics and evolutionary analysis of Chlorella variabilis-infecting viruses demarcate criteria for defining species of giant viruses.

Chloroviruses exhibit a close relationship with their hosts with the phenotypic aspect of their ability to form lytic plaques having primarily guided the taxonomy. However, with the isolation of viruses that are only able to complete their replication cycle in one strain of Chlorella variabilis, systematic challenges emerged. In this study, we described the genomic features of 53 new chlorovirus isolates and used them to elucidate part of the evolutionary history and taxonomy of this clade. Our analysis revealed new chloroviruses with the largest genomes to date (>400 kbp) and indicated that four genomic features are statistically different in the viruses that only infect the Syngen 2-3 strain of C. variabilis (OSy viruses). We found large regions of dissimilarity in the genomes of viruses PBCV-1 and OSy-NE5 when compared with the other genomes. These regions contained genes related to the interaction with the host cell machinery and viral capsid proteins, which provided insights into the evolution of the replicative and structural modules in these giant viruses. Phylogenetic analysis using hallmark genes of Nucleocytoviricota revealed that OSy-viruses evolved from the NC64A-viruses, possibly emerging as a result of the strict relationship with their hosts. Merging phylogenetics and nucleotide identity analyses, we propose strategies to demarcate viral species, resulting in seven new species of chloroviruses. Collectively, our results show how genomic data can be used as lines of evidence to demarcate viral species. Using the chloroviruses as a case study, we expect that similar initiatives will emerge using the basis exhibited here.IMPORTANCEChloroviruses are a group of giant viruses with long dsDNA genomes that infect different species of Chlorella-like green algae. They are host-specific, and some isolates can only replicate within a single strain of Chlorella variabilis. The genomics of these viruses is still poorly explored, and the characterization of new isolates provides important data on their genetic diversity and evolution. In this work, we describe 53 new chlorovirus genomes, including many isolated from alkaline lakes for the first time. Through comparative genomics and molecular phylogeny, we provide evidence of genomic gigantism in chloroviruses and show that a subset of viruses became highly specific for their hosts at a particular point in evolutionary history. We propose criteria to demarcate species of chloroviruses, paving the way for an update in the taxonomy of other groups of viruses. This study is a new and important piece in the complex puzzle of giant algal viruses.

The Effect of Polyethylene Microplastics on Growth and Antioxydant Response of Oscillatoria Princeps and Chlorella Pyrenoidosa.

This study investigated the impacts of polyethylene microplastics (PE-MPs) with varying particle sizes (13μm and 6.5μm) on the growth and antioxidant responses of two freshwater algae species, Oscillatoria princeps (O. princeps) and Chlorella pyrenoidosa (C. pyrenoidosa). The results revealed a significant reduction in chlorophyll a content in both algal species upon exposure to PE-MPs, indicating a disruption of photosynthesis. Furthermore, Superoxide Dismutase (SOD) activity decreased in O. princeps, while Catalase (CAT) activity increased in both species, indicating complex physiological responses to microplastic stress. Notably, phycotoxin levels in O. princeps decreased with PE-MP exposure, while those in C. pyrenoidosa increased, particularly with 6.5μm PE-MPs. These findings underscore the potential toxic effects of PE-MPs on freshwater algal growth and metabolism, as well as their influence on toxin production. This study contributes valuable insights into the ecotoxicological impacts of microplastics in freshwater environments, highlighting the need for further research on their biological effects and environmental health implications.

NBF2, an Algal Fiber-Rich Formula, Reverses Diabetic Dyslipidemia and Hyperglycemia In Vivo.

Ulva prolifera, known as Aonori in Japan, is an edible alga species that is mass-cultivated in Japan. Supplementation with Aonori-derived biomaterials has been reported to enhance metabolic health in previous studies. This was an experimental study that evaluated the metabolic health effects of NBF2, a formula made of algal and junos Tanaka citrus-derived biomaterials, on obesity and type 2 diabetes (T2DM). We used 18 obese and hyperglycemic Otsuka Long-Evans Tokushima Fatty (OLETF) rats that were assigned randomly to three groups of six animals: a high-dose NBF2 drink (20 mg/kg) group, a low-dose (10 mg/kg) NBF2 drink group and the control group that received 2 mL of tap water daily for a total of six weeks. We also used eight LETO rats as the normal control group. In addition to the glucose tolerance test (OGTT), ELISA and real-time PCR assays were performed. High-dose and lowdose NBF2 improved insulin sensitivity, as well as glycemic and lipid profiles, as compared with control rats. The OGTT showed that both NBF2 groups and LETO rats had normalized glycemia by the 90-min time-point. NBF2 up-regulated PPARα/γ-mRNA and Sirt2-mRNA gene expressions in BAT and improved the blood pressure profile. These findings suggest that the NBF2 formula, which activates PPAR-α/γ mRNA and Sirt2-mRNA, may reverse dyslipidemia and hyperglycemia in T2DM.

Investigating the Anti-Inflammatory Activity of Various Brown Algae Species.

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.

UV-B light (radiation) affects the metabolism of pigments and fatty acids in green algae Edaphochlorella mirabilis and Klebsormidium flaccidum in vitro

Algae offer a rich source of bioactive compounds suitable for food products and bioenergy. Environmental challenges such as nutrient scarcity, extreme pH and temperature, high light intensity, and UV radiation usually trigger algae to produce excess of lipids, antioxidants, and other bioprotective molecules as part of their adaptations for survival. Algal cultivation provides proteins, lipids, carbohydrates, vitamins, antioxidants, and trace elements. This study focused on understanding how UV-B irradiance, as an abiotic stressor, can influence the growth and metabolite production of two green algal species, Edaphochlorella mirabilis (Chlorophyta) and Klebsormidium flaccidum (Charophyta). Using a temporary immersion system bioreactor for in-vitro algal growth, the results showed no significant difference in biomass for both algal species after the exposure to UV-B rays. However, the assessment of malondialdehyde levels revealed a significantly higher tendency towards lipid peroxidation in treated E. mirabilis (+ 90 %) compared to control. Conversely, K. flaccidum did not display significant differences, thereby highlighting a more advanced adaptive capacity against UV-B radiation. Overall, both algal species treated with UV-B showed increased pigment accumulation. K. flaccidum exhibited an average pigment increase of over 53 %, while E. mirabilis showed a lower increase, over 30 % on average. The notable rise in antioxidant compounds (lutein, β-carotene, and chlorophyll a) in UV-B exposed K. flaccidum samples also suggested a more suitable adaptive strategy to mitigate oxidative stress in Charophyta. In K. flaccidum, the increase in polyunsaturated fatty acids can be associated with increased production of antioxidant compounds. Conversely, E. mirabilis appeared to protect itself by decreasing polyunsaturated fatty acids in favor of saturated ones. In both algal species, the increase in secondary metabolites under UV stress highlighted potential as a novel food source for human consumption, deserving further investigation.

Unraveling the residual sludge-mediated waste transformation and physiological regulation mechanism of Tetradesmus obliquus

The accumulation of residual sludge as process waste from water treatment engineering needs to be addressed urgently. Tetradesmus obliquus is an important algal species in the field of wastewater treatment. In this study, T. obliquus was cultured in different sludge extract to determine its ability to utilize wastes from the liquid phase and convert them into biomass, and to analyze the response of the microalgae to toxic stress using proteomics. The results showed that the sludge extract medium was superior to the BG11 medium in accumulating biomass, with dry weights, proteins and polysaccharides at least 1.09, 1.12 and 1.28 times higher than those of BG11 medium. In toxic group, T. obliquus reduced TOC from an initial 426.8±20.0 mg/L to 180.4±8.5 mg/L with a simultaneous 48.4 % reduction in toxicity. Toxic sludge extract produced greater damage to the photosystem of T. obliquus compared to the blank, significantly inhibiting the expression of two photosystem II core proteins, A0A383VSL5 (0.290 down) and A0A383V2Z3 (0.308 down), on day 5. However, these impairments were reversible, and at day 20, the expression of A0A383VSL5 was not inhibited, the inhibitory effect of A0A383V2Z3 (0.575 down) was attenuated. These results fill a gap on the treatment of various types of residual sludge by T. obliquus and provide promising strategies for microalgae treatment of residual sludge, whether non-toxic or toxic.

Assessing the influence of macroalgae and micropredators on the early life success of the echinoid Diademaafricanum

The sea urchin Diadema africanum is an herbivore that has a significant influence on subtidal rocky reef communities on the Canary Islands, facilitating transitions between macroalgal beds and barren grounds. Barren grounds in the archipelago are characterized by a dominance of crustose coralline algae and a lack of invertebrates and fishes compared to macroalgal beds, which are mainly dominated by brown algae. To assess the impact of these benthic community states on the early life success of D. africanum, a manipulative study was conducted in September 2021 at four sites on the eastern coast of Tenerife Island, characterized by the availability of historical settlement rates and adult data for this species. For this purpose, experimental larval collectors modified with a hollow algae-container were employed to examine sea urchin settlement rates in response to two dominant algal species, Lobophora schneideri, in macroalgal beds and crustose coralline algae (CCA) in barren grounds. Statistical analysis revealed significant spatial differences in sea urchin settlement and the interaction between site and treatment response. Specifically, the site with higher sea urchin settlement exhibited lower numbers of D. africanum settlers in treatments containing L. schneideri than in the Control and CCA treatments. Three decapod species (the pistol shrimp Alpheus macrocheles, and the crabs Lophozozimus incisus, and Pachygrapsus marmoratus) negatively correlated with D. africanum settlers. These results suggest that larval supply, L. schneideri beds, and micropredator abundance play a role in the early life success of this species. This may imply a community stability mechanism that helps to prevent shifts between alternative stable states.

Eutrophication promotes resource use efficiency and toxin production of Microcystis in a future climate warming scenario

Addressing the risks of cyanobacterial blooms and toxin production under ongoing and accelerating eutrophication and climate warming is crucial for both water ecosystem services and human health. Therefore, we here explored the interactive effects of eutrophication and warming on freshwater ecosystems, focusing on Microcystis and its cyanotoxin production. We employed a large-scale mesocosm system simulating future climate warming scenarios in concert with varying degrees of nutrient enrichment. We explored the full range of identified cyanobacterial toxins and cyanotoxin-producing genes under different experimental conditions and assessed the effects of both eutrophication and warming on both phytoplankton community structure (algal densities, community stability) and function (resource use efficiency, RUE). We show here that eutrophication increases the RUE of Microcystis and promotes an increase in toxin-producing genes, leading to a substantial increase in the dominance of Microcystis. This increase correlates with enhanced cyanotoxin production, a trend exacerbated under the influence of future climate warming, suggesting interactions between eutrophication and climate warming on Microcystis ecology and cyanotoxin dynamics. Hence, heatwaves and eutrophication lead the phytoplankton community to be dominated by a minority of algal species with higher toxic capacity. In a broader context, our study underscores the urgent need for holistic management strategies, addressing both nutrient control and climate mitigation, to effectively manage the escalating ecological risks associated with cyanobacterial dominance and toxin production.

Evolution of the regulatory subunits for the heteromeric acetyl-CoA carboxylase.

The committed step for de novo fatty acid (FA) synthesis is the ATP-dependent carboxylation of acetyl-coenzyme A catalysed by acetyl-CoA carboxylase (ACCase). In most plants, ACCase is a multi-subunit complex orthologous to prokaryotes. However, unlike prokaryotes, the plant and algal orthologues are comprised both catalytic and additional dedicated regulatory subunits. Novel regulatory subunits, biotin lipoyl attachment domain-containing proteins (BADC) and carboxyltransferase interactors (CTI) (both three-gene families in Arabidopsis) represent new effectors specific to plants and certain algal species. The evolutionary history of these genes in autotrophic eukaryotes remains elusive, making it an ongoing area of research. Analyses of potential protein-protein and co-occurrence interactions, informed by gene network patterns using the STRING database, in Arabidopsis thaliana and Chlamydomonas reinhardtii unveil intricate gene associations with ACCase, suggesting a complex interplay between FA synthesis and other cellular processes. Among both species, a higher number of co-expressed genes was identified in Arabidopsis, indicating a wider potential regulatory network of ACCase in plants. This review investigates the extent to which these genes arose in autotrophic eukaryotes and provides insights into their evolutionary trajectory. This article is part of the theme issue 'The evolution of plant metabolism'.

Persistent Organic Pollutants in Water and their Microalgae Based Bioremediation

ABSTRACT: This appraisal overviews Persistent Organic Pollutants and suggests a novel approach to their bioremediation using algae as an agent. Compared to older techniques using different bacteria, a greenway for wastewater treatment is more environmentally sustainable and friendlier. It has a lot of potential to use new bioremediation technology that uses cyanobacteria and algae to remove variety of organic pollutants. Several organisms' health and well-being may be at risk due to the abundance of organic pollutants in the environment. Household garbage, agriculture, and industry are some of the numerous man-caused contributors to organic pollutants that pollute water across the planet. Wastewater needs to be cleaned before it may be discharged into rivers. As algae-based wastewater treatment systems don't produce any secondary pollutants and are environmentally sustainable, they are growing in popularity. A variety of organic pollutants can be absorbed and accumulated by algae and cyanobacteria at different rates, contingent upon the type of contaminant, the physio-chemical assets of waste water, as well as the specific species of algae involved. Moreover, phytoremediation is a more affordable option for breaking down organic pollutants than traditional methods. Algal biomass produced through phycoremediation might also play a significant role in the bioenergy value chain. Hence the emphasis of this paper is on an over view of Persistent Organic Pollutants, cyanobacteria and microalgae species, which have the potential to rid water systems of several organic pollutants.

Polystyrene microplastics enhanced the photo-degradation and -ammonification of algae-derived dissolved organic matters

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 (∼38 % vs. ∼22 %) 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.

Red Seaweed (Rhodophyta) Phycocolloids: A Road from the Species to the Industry Application.

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.

Enhancement of the activity of a porphyranase by fusing a polymerization-inducing domain

Porphyra is one of the most economically valuable species of red algae, with porphyran being its primary bioactive polysaccharide. Highly active enzymes play a significant role in the research and development of porphyran. This study identified a PKD domain within a polysaccharide-binding protein, displaying an apparent molecular weight (Mw) of 20.20 kDa that is approximately twice the theoretical value, thereby suggesting the possibility of self-aggregation. By fusing it with porphyranase Por16B_Wf, a chimeric enzyme PKD-Por16B was constructed. It was confirmed that the fusion enzyme successfully assembles into an aggregation under the mediation of PKD domain, with its apparent Mw (65.13 kDa) significantly higher than theoretical Mw (46.02 kDa). The activity of PKD-Por16B was remarkably enhanced from 65.31 U/mg to 325.69 U/mg, accompanied by an improvement in enzymatic stability. Meanwhile, the hydrolysis pattern of PKD-Por16B remained unaltered in comparison to that of Por16B_Wf, indicating no significant deviation in its substrate specificity or reaction mechanism. These results suggest the feasibility of a strategy based on domain-induced aggregation to enhance enzyme activity, which is easy and economical.

Environmental Implications of Ionic Liquid and Deep Eutectic Solvent in Geothermal Application: Comparing Traditional and New Approach Methods.

The significant surge of ionic liquids (ILs) research over the past decade has led to the formation of various novel ionic liquid compounds and their diverse applications. Enhanced geothermal systems (EGS) for geothermal power generation are an emerging IL application as a heat extraction fluid. The once widely held belief in the environmentally friendly characteristics of ionic liquids, mainly due to their insignificant vapor pressure, is now being scrutinized. It has become apparent that while ILs do not readily evaporate into the atmosphere, they are not guaranteed to remain entirely isolated from the environment. Recent attention has been directed toward toxicological studies, including ecotoxicity impacts, with the long-accepted assumption of ILs having low toxicity being invalid. This paper aims to shed light on the toxicity of hexylepyradinium bromide (HPyBr) IL and a deep eutectic solvent (DES) comprising choline chloride with magnesium chloride hexahydrate (ChCl:MgCl2·6H2O) to five test species, an algal species (Raphidocelis subcapitata), the water flea (Ceriodaphnia dubia and Daphina magna), the fathead minnow (Pimephales promelas), and the earthworm (Eisenia fetida), to measure acute and chronic toxicity. Additionally, new approach methods (NAMs) are presented using the fathead minnow embryo and the rainbow trout (Oncorhynchus mykiss) gill cell line and the RTgill-W1 assay to compare sensitivity across species. Overall, ChCl:MgCl2·6H2O displayed lower toxicity, while HPyBr demonstrated higher toxicity, highlighting the need for caution in handling it to prevent harm to aquatic ecosystems. Comparative analysis underscored the potential threat of ChCl:MgCl2·6H2O to aquatic life, highlighting the cumulative effects of the environmental components.

Algae Modified Alginate Beads for Improved Cd(II) Removal from Aqueous Solutions

The aim of this research was to synthesize alginate beads. The beads were modified with a mixture of three different species of algae. Both synthesized beads were evaluated for the efficiency of Cd(II) removal from aqueous solutions as one of the currently most sustainable metal removal methods. The focus was on the characterization of synthesized beads and their stability. The characterization was performed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The specific surface area was determined. Cd(II) ion standard solutions were brought into contact with unmodified and modified beads. The experimental results showed that the most influential factors on biosorption are pH value and temperature. The maximum biosorption of Cd(II) ions was achieved at 181.0 mg/g. Kinetic and thermodynamic studies were carried out. The data obtained followed pseudo-second-order kinetics.