Adaptation and potential culture of wild Amphipods and Mysids as potential live feed in aquaculture: a review.

Live foods such as phytoplankton and zooplankton are essential food sources in aquaculture. Due to their small size, they are suitable for newly hatched larvae. Artemia and rotifer are commonly used live feeds in aquaculture; each feed has a limited dietary value, which is unsuitable for all cultured species. Whereas, copepod and cladocerans species exhibit favorable characteristics that make them viable candidates as sources of essential nutrients for hatchery operations. Due to their jerking movements, it stimulates the feeding response of fish larvae, and their various sizes make them suitable for any fish and crustacean. Even though Artemia is the best live feed due to its proficient nutritional quality, the cost is very expensive, which is about half of the production cost. A recent study suggests the use of amphipods and mysids as alternative live feeds in aquaculture. High nutritional value is present in amphipods and mysids, especially proteins, lipids, and essential fatty acids that are required by fish larvae during early development. Amphipods and mysids are considered abundant in the aquatic ecosystem and have been used by researchers in water toxicity studies. However, the culture of amphipods and mysids has been poorly studied. There is only a small-scale culture under laboratory conditions for scientific research that has been performed. Thus, further research is required to find a way to improve the mass culture of amphipods and mysids that can benefit the aquaculture industry. This review article is intended to provide the available information on amphipods and mysids, including reproductive biology, culture method, nutritional value, feed enhancement, and the importance of them as potential live feed in aquaculture. This article is useful as a guideline for researchers, hatchery operators, and farmers.

ArHsp90 is important in stress tolerance and embryo development of the brine shrimp, Artemia franciscana.

Females of the extremophile crustacean, Artemia franciscana, either release motile nauplii via the ovoviviparous pathway or encysted embryos (cysts) via the oviparous pathway. Cysts contain an abundant amount of the ATP-independent small heat shock protein that contributes to stress tolerance and embryo development, however, little is known of the role of ATP-dependent molecular chaperone, heat shock protein 90 (Hsp90) in the two processes. In this study, a hsp90 was cloned from A. franciscana. Characteristic domains of ArHsp90 were simulated from the deduced amino acid sequence, and 3D structures of ArHsp90 and Hsp90s of organisms from different groups were aligned. RNA interference was then employed to characterize ArHsp90 in A. franciscana nauplii and cysts. The partial knockdown of ArHsp90 slowed the development of nauplius-destined, but not cyst-destined embryos. ArHsp90 knockdown also reduced the survival and stress tolerance of nauplii newly released from A. franciscana females. Although the reduction of ArHsp90 had no effect on the development of diapause-destined embryos, the resulting cysts displayed reduced tolerance to desiccation and low temperature, two stresses normally encountered by A. franciscana in its natural environment. The results reveal that Hsp90 contributes to the development, growth, and stress tolerance of A. franciscana, an organism of practical importance as a feed source in aquaculture.

Acute and subacute toxicological evaluation of the ethanol leaf extract of Morus mesozygia stapf. (Moraceae) in rodents.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditionally, the Morus mesozygia tree leaf has been used to manage maladies such as peptic ulcer, hyperglycemia, dermatitis, rheumatism, stomach-ache, arthritis, cough, malignancies, and malaria in parts of Africa. AIM OF THE STUDY: The study aimed to evaluate the potential of ethanol leaf extract of Morus mesozygia (EEMm) to induce toxicity by employing both acute and sub-acute oral toxicity experimental models. MATERIAL AND METHODS: The extract's cytotoxicity was studied using brine shrimps (Artemia salina) lethality assay (BSLA), while in the acute toxicity test, male and female mice were administered a single oral dose of EEMm (2000 mg/kg). Male and female Wistar rats received repeated doses of 100 or 500 mg/kg EEMm orally for 28 days in the sub-acute toxicity experiment. The phytochemical analysis of EEMm was done using the HPLC. RESULTS: The BSLA revealed a moderate cytotoxic potential of the extract, with an LC50 of 567.13 ± 0.27 µg/mL. All the animals survived the acute toxicity test, with no significant changes in the relative organ weights, suggesting that LD50 is greater than 2000 mg/kg. The animal weights did not vary significantly in the sub-acute toxicity test neither were the alterations in biochemical and hematological tests pronounced, although the histoarchitectures of the kidney, liver and spleen indicated slight anomalies in the evaluated animals. The HPLC analysis revealed the presence of quercetin, ferulic acid, rutin, caffeic acid, morin and gallic acid. CONCLUSIONS: Ethanol leaf extract of Morus mesozygia demonstrated a safe toxicity profile in rodents, supporting its broad folkloric use in African ethnomedicine.

Eco-friendly green synthesis of AgNPs from Elaeocarpus serratus fruit extract: potential to antibacterial, antioxidant, cytotoxic effects of colon cancerous cells (HT-29) and its toxicity assessments of marine microcrustacean Artemia nauplii.

BACKGROUND: The present work demonstrated the green synthesis and characterization of silver nanoparticles (AgNPs) utilizing Elaeocarpus serratus fruit extract. The study examined the effectiveness of phytocompounds in fruit extract in reducing Ag+ to Ag° ions. METHODS: The water-soluble biobased substance production from silver ions to AgNPs in 45 min at room temperature. Surface plasmon resonance (SPR) peak was seen in the UV-visible absorption spectrum of the biologically altered response mixture. Examination with X-ray diffraction (XRD) showed that AgNPs are strong and have a face-centered cubic shape. Scanning electron microscope (SEM) investigation proved the production of AgNPs in a cuboidal shape. RESULTS: The AgNPs demonstrated remarkable antibacterial activity and a potent capacity to neutralize DPPH (2,2-Diphenyl-1-picrylhydrazyl) radicals. The highest growth inhibition was found for E. serratus against S. dysenteriae (18.5 ± 1.0 mm) and S. aureus (18 ± 1.2 mm). These nanoparticles exhibited robust antiradical efficacy even at low concentrations. The AgNPs additionally exhibited cytotoxic effects on (HT-29) human colon adenocarcinoma cancer cells. The MTT assay (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) indicated an inhibitory concentration (IC50) value of 49.1 ± 2.33 µg/mL for AgNPs, contrasting with the untreated cells of the negative control. The biotoxicity assessment using A. salina displayed mortality rates ranging from 8 to 69.33%, attributable to the E. serratus synthesized AgNPs. CONCLUSIONS: In our results concluded that simply first-hand information on that E. serattus fruit extract synthesized AgNPs were efficiently synthesized without the addition of any hazardous substances, and that they may be a strong antibacterial, antioxidant, and potential cytotoxic effects for the treatment of colon carcinoma cell lines.

Antiproliferative activities of some selected Nigerian medicinal plants against breast, liver, and cervical cancer cells.

BACKGROUND: Phytochemicals have become a growing source of alternative medicine in developing countries due to the poor prognosis, high cost of conventional pharmaceuticals, and undesirable effects associated with mainstream cancer treatment. OBJECTIVE: This study was aimed at investigating the anticancer effect of some selected Nigerian medicinal plants used in cancer treatment. These include ethanol extracts of Dialium guineense root (DGR), Dialium guineense leaves (DGL), Jateorhiza macrantha leaves (JML), Musanga cecropioides leaves (MCL), Musanga cecropioides stembark (MCSB), Piptadeniastrum africanum stembark (PASB), Piptadeniastrum africanum root (PAR), Pupalia lappacea flower tops (PLF), Raphiostylis beninensis root (RBR), Raphiostylis beninensis leaves (RBL), Ritchiea capparoides leaves (RCL), Ritchiea capparoides stembark (RCSB), and Triplochiton scleroxylon stembark (TSB). METHODS: The cytotoxic activity of the extracts was examined using a brine shrimp lethality assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against three cancer cell lines, including MCF-7, HUH-7, and HeLa. The selectivity of all extracts towards cancer cells was investigated using normal lung fibroblasts (MRC-5). Cell migration and colony-forming assays of active extracts against MCF-7 cells were also performed. Additionally, the total polyphenolic contents of the active extracts were estimated using standard methods. RESULTS: The extract of PASB had the highest cytotoxicity (LC50 = 1.58 µg/mL) on the brine shrimps compared to vincristine sulphate (LC50 = 2.24 µg/mL). In the cell viability assay, all the extracts produced significant (p < 0.05) growth inhibitory effects against all cell lines tested in a dose-dependent manner. All extracts were selective to cancer cells at varying degrees. Worth mentioning are the extracts of MCL, DGR, RBR, and PASB, which exhibited 14-, 7-, 6- and 2-fold selectivity toward MCF-7 cancer cells relative to normal lung fibroblast (MRC-5), respectively. These four extracts also significantly inhibited cell migration and colony formation in MCF-7-treated cells in dose-dependent manners. Considerable amounts of phenolics, flavonoids, and proanthocyanidins were detected in all extracts evaluated. CONCLUSION: These findings advocate the continued development of MCL, DGR, RBR, and PASB as potential chemotherapeutic agents.

A combined toxicological impact on Artemia salina caused by the presence of dust particles, microplastics from cosmetics, and paracetamol.

Environmental pollution poses a significant and pressing threat to the overall well-being of aquatic ecosystems in modern society. This study showed that pollutants like dusts from AC filter, fan wings and Traffic dust PM 2.5 were exposed to Artemia salina in pristine form and in combination. The findings indicated that exposure to multi-pollutants had a detrimental effect on the hatching rates of A. salina cysts. Compared to untreated A. salina, the morphology of adult (7th day old) A. salina changed noticeably after each incubation period (24-120 h). Oxidative stress increased considerably as the exposure duration increased from 24 to 120 h compared to the control group. There was a time-dependent decline in antioxidant enzyme activity and total protein concentration. When all particles were used all together, the total protein content in A. salina decreased significantly. All particles showed a considerable decline in survival rate. Those exposed to traffic dust particles showed significantly higher levels of oxidative stress and antioxidant activity than those exposed to other particles.

Preliminary assessment of environmental safety (ecosafety) of dextrin-based nanosponges for environmental applications.

The ability to employ waste products, such as vegetable scraps, as raw materials for the synthesis of new promising adsorbing materials is at the base of the circular economy and end of waste concepts. Dextrin-based nanosponges (D_NS), both cyclodextrin (CD) and maltodextrin (MD), have shown remarkable adsorption abilities in the removal of toxic compounds from water and wastewater, thus representing a bio-based low-cost solution which is establishing itself in the market. Nevertheless, their environmental safety for either aquatic or terrestrial organisms has been overlooked, raising concern in terms of potential hazards to natural ecosystems. Here, the environmental safety (ecosafety) of six newly synthesized batches of D_NS was determined along with their full characterization by means of dynamic light scattering (DLS), thermogravimetric analysis (TGA), Fourier transformed infrared spectroscopy with attenuated total reflection (FTIR-ATR) and transmission electron microscopy (SEM). Ecotoxicity evaluation was performed using a battery of model organisms and ecotoxicity assays, such as the microalgae growth inhibition test using the freshwater Raphidocelis subcapitata and the marine diatom Dunaliella tertiolecta, regeneration assay using the freshwater cnidarian Hydra vulgaris and immobilization assay with the marine brine shrimp Artemia franciscana. Impact on seedling germination of a terrestrial plant of commercial interest, Cucurbita pepo was also investigated. Ecotoxicity data showed mild to low toxicity of the six batches, up to 1 mg/mL, in the following order: R. subcapitata > H. vulgaris > D. tertiolecta > A. franciscana > C. pepo. The only exception was represented by one batch (NS-Q+_BDE_(GLU2) which resulted highly toxic for both freshwater species, R. subcapitata and H. vulgaris. Those criticalities were solved with the synthesis of a fresh new batch and were hence attributed to the single synthesis and not to the specific D_NS formulation. No effect on germination of pumpkin but rather more a stimulative effect was observed. To our knowledge this is the first evaluation of the environmental safety of D_ NS. As such we emphasize that current formulations and exposure levels in the range of mg/mL do not harm aquatic and terrestrial species thus representing an ecosafe solution also for environmental applications.

In vitro evaluation of methanol extracts of edible fungi Pleurotus ostreatus and Lentinula edodes against Rhyssomatus nigerrimus Fahraeus.

The study aimed to evaluate the insecticidal activity of extracts of edible mushrooms Pleurotus ostreatus and Lentinula edodes against Rhyssomatus nigerrimus. Methanol:water extracts (70:30) of P. ostreatus and L. edodes were made and evaluated in two in vitro tests (exposure and immersion toxic effect) against R. nigerrimus. Subsequently, the toxicity test of the extracts against Artemia salina was evaluated. These extracts were subjected to colorimetric tests and gas chromatography-mass spectrometry. The results showed a mortality effect against R. nigerrimus of 50% for the P. ostreatus 2 extracts at a concentration of 20% in the immersion test. Likewise, in the toxic effect test, 90% mortality was observed after five days of exposure to a concentration of 10%. On the other hand, for the toxicity test, the extract that showed the values with the highest mortality against A. salina was P. ostreatus, starting with 80% mortality at 100µg/mL. The functional groups present in the extracts were saponins, coumarins, and alkaloids. Furthermore, the presence of more than 7 compounds in the mushroom extracts evaluated is reported. This study demonstrates the insecticidal activity of P. ostreatus and L. edodes fungal extracts and indicates the importance of using different in vitro tests to elucidate the mechanism of action for future studies.

Research on the Artemia nauplii microorganism compositions based on metagenomics next-generation sequencing.

Vibrio species represent the predominant and significant pathogen in global marine fish and shellfish aquaculture. Vibrio species are ubiquitously presented in Artemia cyst hatcheries, and their notable colonization in live prey, particularly Artemia nauplii, leads to the transmission of these pathogens into the digestive system of larval organisms, causing serious problems in Vibriosis in marine aquaculture. To eliminate the Vibriospecies in Artemia nauplii, trichloroisocyanuric acid (TCCA) was used for sterilization of the nauplii. In this study, 3 different concentrations, including 0.5 ppm (FA group), 1.0 ppm (FB group) and 1.5 ppm (FC group) of TCCA were used to treat nauplii for 25 min, and then genomic DNA of the different groups were extracted followed by metagenomic next-generation sequencing (NGS). Bioinformatics analysis was applied and the results indicated that Proteobacter constituted the predominant component within each group at the phylum level, albeit accounting for only 58.68% in the FB group, which was significantly lower than in other groups (>86%). The relative abundance of Vibrio species at genus level showed that when compared with the control group, the FB group (15.8%) was reduced by 25.5%. Beta diversity showed differences between the FB group and the other groups, suggesting that treatment with 1.0ppm TCCA for 25 min would obviously reduce the Vibrio in Artemia nauplii. In conclusion, the Vibrio species were significantly reduced after treatment with TCCA, indicating that TCCA might be an alternative to antibiotics used for live food sterilization in marine aquaculture.

Ceratocarpus arenarius: Botanical Characteristics, Proximate, Mineral Composition, and Cytotoxic Activity.

Ceratocarpus arenarius (Chenopodiaceae) is an under-investigated annual plant that occurs in dry areas stretching from eastern and south-eastern Europe to East Asia. This article presents the botanical characterization and examination of proximate parameters, minerals and cytotoxic activity of C. arenarius that grows wild in Kazakhstan. The results of morphological analysis using a light microscope, based on cross-sections of stems, roots and leaves, provide the necessary data to develop a regulatory document for this herbal substance as a raw material for use in the pharmaceutical, cosmetic and food industries. The investigated proximate characteristics included moisture content (6.8 ± 0.28%), ash (5.9 ± 0.40%), fat (12.5 ± 21.28%) and protein (392.85 ± 25.50). The plant is also rich in minerals (mg/100 g dry weight); Na (20.48 ± 0.29), K (302.73 ± 1.15), Zn (4.45 ± 0.35), Fe (1.18 ± 0.03), Cu (0.11 ± 0.02), Mn (0.76 ± 0.01), Ca (131.23 ± 0.09) and Mg (60.69 ± 0.72). The ethanolic extract of C. arenarius showed no acute toxicity against the brine shrimp nauplii.

A response surface model to examine the reactive red 239 sorption behaviors on Rhizoclonium hieroglyphicum: isotherms, kinetics, thermodynamics and toxicity analyses.

The present study is an attempt to investigate the potentiality of Rhizoclonium hieroglyphicum in the removal of reactive red 239 (RR239) from aqueous solution and to assess the toxicity of the treated dye solution. Optimisation of the process variables namely dye and biosorbent concentrations, pH, temperature and incubation time for RR239 removal was performed using Response Surface Methodology (RSM) assisted Box Behnken Design (BBD) model. The recycling and regeneration efficiency of the dye adsorbed alga was evaluated using different eluents under optimized conditions. Further to understand the adsorption mechanism, isotherms, kinetics and thermodynamic studies were performed. UV-vis and FT-IR spectroscopy was employed to confirm the interaction between the adsorbate and biosorbent. The nature of the treated dye solution was assessed using phyto, microbial and brine shrimp toxicity studies. On the basis of quadratic polynomial equation and response surfaces given by RSM, 90% decolorization of RR239 was recorded at room temperature under specified optimal conditions (300 mg/L of dye, 500 mg/L of biosorbent, pH 8 and 72 h of contact time). Desorption experiments demonstrated 88% of RR239 recovery using 0.1 N acetic acid as an eluent and 81% of dye removal in regeneration studies. The data closely aligned with Freundlich isotherm (R2 - 0.98) and pseudo-second-order kinetic model (R2 - 0.9671). Thermodynamic analysis revealed that the process of adsorption was endothermic, spontaneous, and favorable. UV-Vis and FT-IR analyses provided evidence for adsorbate-biosorbent interaction, substantiating the process of decolorization. In addition, the results of phyto, microbial and brine shrimp toxicity assays consistently confirmed the non-toxic nature of the treated dye. Thus, the study demonstrated that R. hieroglyphicum can act as a potent bioremediation agent in alleviating the environmental repercussions of textile dyeing processes.

Naturally weathered polypropylene microplastic from environment and its toxic behaviour in Artemia salina.

The increasing use of polypropylene (PP) in consumer products leads to the microplastic (PP MPs) contamination of the aquatic ecosystems. Comprehensive toxicological studies of weathered/aged and new PP MPs with Artemia salina are a need of the hour. Our study explores the toxicological differences between naturally weathered (aged) and prepared new PP MPs on Artemia salina. Both the weathered and new PP MPs were prepared using controlled grinding and sieving at ≤ 125 µm. Artemia salina was treated with different concentrations (0.25, 0.5, and 1 mg/mL) of PP MP particles for up to 48 h. The uptake of weathered PP MP particles by Artemia salina was higher than the new PP MPs. The accumulation of PP MP particles was found in the intestine. There was increased oxidative stress recorded in the animal treated with the weathered PP MPs than the new PP MPs. Artemia salina treated with weathered PP MPs showed higher ROS generation and increased, activity of oxidative enzymes like LPO, SOD, and CAT. Collectively, our findings underscore the detrimental effects of weathered and prepared new PP MPs on Artemia salina, which is an ecologically significant species of zooplankton. There is an urgent need and effective measures required to address plastic disposal strategies in an environmentally safe manner.

Chromosome-Level Assembly of Artemia franciscana Sheds Light on Sex Chromosome Differentiation.

Since the commercialization of brine shrimp (genus Artemia) in the 1950s, this lineage, and in particular the model species Artemia franciscana, has been the subject of extensive research. However, our understanding of the genetic mechanisms underlying various aspects of their reproductive biology, including sex determination, is still lacking. This is partly due to the scarcity of genomic resources for Artemia species and crustaceans in general. Here, we present a chromosome-level genome assembly of A. franciscana (Kellogg 1906), from the Great Salt Lake, United States. The genome is 1 GB, and the majority of the genome (81%) is scaffolded into 21 linkage groups using a previously published high-density linkage map. We performed coverage and FST analyses using male and female genomic and transcriptomic reads to quantify the extent of differentiation between the Z and W chromosomes. Additionally, we quantified the expression levels in male and female heads and gonads and found further evidence for dosage compensation in this species.

Enhanced sequestration of Pb2+ and Cu2+ by Artemia cyst shell supported nano-Mg composite and the potential photocatalytic performance of carbonized exhausted-adsorbent.

This study reported a new strategy for enhanced Pb2+ and Cu2+ sequestration by Artemia cyst shell (shell) supported nano-Mg from aqueous solutions and the carbonated exhausted-adsorbents sequenced potential application in photo-catalyst, which obtained two expected results. One is that the immobilization of nano-Mg onto Artemia cyst shell (shell-Mg) can greatly strengthen the adsorption effect of the neat cyst shell on Pb2+ and Cu2+. The adsorption capacities of shell-Mg for both metal ions reached to 622.01 and 313.91 mg/g, which was 10-15 and 30-50 times that of the neat shell respectively. And shell-Mg has strong selectivity, which was approximately 2-4 times that of shell. The shell-Mg can be used to retrieve Pb2+ and Cu2+ from aqueous solutions efficiently. Another is that the carbonated exhausted-adsorbents (C-shell-Mg-Pb and C-shell-Mg-Cu) showed their potential photocatalytic degradation effects on congo red under pH = 4 condition, the decolorization rate reached to 61.19% and 80.39% respectively. Reuse of exhausted adsorbents can avoid the secondary pollution caused by the regeneration, extend the utilization value of exhausted adsorbents, and provide a new viewpoint for the reuse of spent bio-nanomaterial adsorbents.

Temporal genetic variation mediated by climate change-induced salinity decline, a study on Artemia (Crustacea: Anostraca) from Kyêbxang Co, a high altitude salt lake on the Qinghai-Tibet Plateau.

The Qinghai-Tibet Plateau is one of the areas the richest in salt lakes and Artemia sites. As a result of climate warming and wetting, the areas of salt lakes on the plateau have been increasing, and the salinities have decreased considerably since 1990s. However, the impact of salinity change on the genetic diversity of Artemia is still unknown. Kyêbxang Co is the highest (4620 m above sea level) salt lake currently with commercial harvesting of Artemia resting eggs in the world, and harbors the largest Artemia population on the plateau. Its salinity had dropped from âˆ¼67 ppt in 1998 to âˆ¼39 ppt in 2019. Using 13 microsatellite markers and the mitochondrial cytochrome oxidase submit I (COI) gene, we analyzed the temporal changes of genetic diversity, effective population size and genetic structure of this Artemia population based on samples collected in 1998, 2007 and 2019. Our results revealed a steady decline of genetic diversity and significant genetic differentiation among the sampling years, which may be a consequence of genetic drift and the selection of decreased salinity. A decline of effective population size was also detected, which may be relative to the fluctuation in census population size, skewed sex ratio, and selection of the declined salinity. In 2007 and 2019, the Artemia population showed an excess of heterozygosity and significant deviation from Hardy-Weinberg Equilibrium (p < 0.001), which may be associated with the heterozygote advantage under low salinity. To comprehensively understand the impact of climate warming and wetting on Artemia populations on the plateau, further investigation with broad and intensive sampling are needed.

Ultrastructural diversity in the shell of Artemia resting eggs.

The shell of Artemia resting egg, which is a delicate multilayered envelope surrounding the inside diapause embryo, plays an important role in the survival strategy of Artemia. To date, the ultrastructure of resting eggshell has been studied for only handful populations, and knowledge about the diversity of shell structure is still limited. In this paper, resting eggs from 13 Artemia populations were studied by transmission electron microscopy. Results show that the basic configuration of resting eggshell is quite conservative, but variations are not uncommon in the fine ultrastructure of each main layer of the shell (e.g., the shape and distribution of the radially oriented pores in the cortical layer; the size, number and arrangement of chambers in the alveolar layer; and the development state of outer cuticular membrane [OCM]). The ultrastructural variation of eggshell seems not to be linked with species and reproductive mode of Artemia. Resting eggs from very high habitats (4300+ m above sea level [a.s.l.]) on Qinghai-Tibet Plateau and certain tropical salterns have a hypoplastic OCM, which may be related to the adaptation to habitat conditions such as low oxygen concentration. RESEARCH HIGHLIGHTS: Comparative study on resting eggs from 13 Artemia populations reveals high diversity in the fine structure of eggshell. Resting eggs from very high (4300+ m a.s.l.) habitats commonly have a hypoplastic OCM.

Chemical, ecotoxicological, cytotoxic, and mutagenic evaluation of gelling agents used in the production of 70% alcohol gel.

With COVID-19, there has been an increase in the use of gelling agents for hand sanitizer production, and as a result, the release of this product into wastewater could induce impacts and adverse reactions in living organisms. Thus, ecotoxicological and cytotoxicological assessments of gelling agents with test organisms from different trophic levels are necessary to assess their environmental safety. For this, seven cellulose-based gelling agents and a polyacrylic acid derivative (C940) were selected for tests with Artemia salina. The most toxic agent was tested on Allium cepa to assess cytotoxicity. The volatile compounds of the gelling agents were analyzed. Cellulose-based gelling agents were not considered toxic according to their LC50, but C940 presented moderate toxicity to A. salina and cytotoxicity to Allium cepa, but without mutagenicity. In addition, C940 contained cyclohexane as a volatile compound. Thus, cellulose-based gelling agents are better environmental options than carbomer for 70% alcohol gel sanitizer.

Diversity and connectedness of brine shrimp viruses in global hypersaline ecosystems.

Brine shrimp (Artemia) has existed on Earth for 400 million years and has major ecological importance in hypersaline ecosystems. As a crucial live food in aquaculture, brine shrimp cysts have become one of the most important aquatic products traded worldwide. However, our understanding of the biodiversity, prevalence and global connectedness of viruses in brine shrimp is still very limited. A total of 143 batches of brine shrimp (belonging to seven species) cysts were collected from six continents including 21 countries and more than 100 geographic locations worldwide during 1977-2019. In total, 55 novel RNA viruses were identified, which could be assigned to 18 different viral families and related clades. Eleven viruses were dsRNA viruses, 16 were +ssRNA viruses, and 28 were-ssRNA viruses. Phylogenetic analyses of the RNA-directed RNA polymerase (RdRp) showed that brine shrimp viruses were often grouped with viruses isolated from other invertebrates and fungi. Remarkably, most brine shrimp viruses were related to those from different hosts that might feed on brine shrimp or share the same ecological niche. A notable case was the novel brine shrimp noda-like virus 3, which shared 79.25% (RdRp) and 63.88% (capsid proteins) amino acid identity with covert mortality nodavirus (CMNV) that may cause losses in aquaculture. In addition, both virome composition and phylogenetic analyses revealed global connectedness in certain brine shrimp viruses, particularly among Asia and Northern America. This highlights the incredible species diversity of viruses in these ancient species and provides essential data for the prevalence of RNA viruses in the global aquaculture industry. More broadly, these findings provide novel insights into the previously unrecognized RNA virosphere in hypersaline ecosystems worldwide and demonstrate that human activity might have driven the global connectedness of brine shrimp viruses.

Population genetics of Artemia urmiana species complex (Crustacea, Anostraca): A group with asymmetrical dispersal and gene flow mediated by migratory waterfowl.

Bird-mediated dispersal of resting eggs is the main mechanism for Artemia dispersal among catchments. The bisexual populations of Artemia urmiana species complex, which is here considered to be a collection of Artemia genetically close to the so-called "Western Asian Lineage", are mostly distributed in central and western Asia (i.e., in regions falling into the Central Asian Flyway of migratory birds) and live in diversified habitats. Little is known about the genetic relationships among these populations. Aiming to understand the population genetic characteristics and the roles of migratory birds on the dispersal and gene flow of this Artemia group, we evaluated the genetic diversity, genetic differentiation, and gene flow among 14 populations, with their altitudes ranging from 540 to 4870 m above sea level, using 13 microsatellite markers. Almost all populations exhibited high genetic diversity and heterozygote excess, which may be a consequence of combined effects of dispersal and hybridization. The global genetic differentiation (FST) value was 0.092, the pairwise FST values were 0.003-0.246. Discriminant analysis of principal components identified three genetic clusters, consisting of Urmia Lake (Iran), Zhundong (Xinjiang, China), and 12 Qinghai-Tibet Plateau populations, respectively. The among-population genetic differentiation seems to be a consequence of isolation by distance and adaptation to diversified habitats induced by altitudinal gradient. Historical gene flows are asymmetrical, and show an evolutionary source-sink dynamics, with Jingyu Lake (Xinjiang, China) population being the major source. These results support our hypothesis that in Qinghai-Tibet Plateau and surrounding areas the bird-mediated dispersal of Artemia may be biased towards from north to south and/or from higher altitude to lower altitude.

Acute toxicity of nanoscale zeolitic imidazolate framework 8 (ZIF-8) to saltwater planktonic species Artemia salina and Nannochloropsis oculata.

Zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs) are metal-organic frameworks (MOFs) that have gained significant attention in various fields due to their unique properties. They have potential applications in drug delivery, gas storage, and catalysis. However, their increasing use raises concerns about their potential environmental impact. Our study evaluates the effects of ≈90 nm ZIF-8 NPs in two planktonic species, the green microalga Nannochloropsis oculata and the brine shrimp Artemia salina. After synthesis and characterization (SEM, EDS, BET, and DLS) of nanoporous ZIF-8 NPs, a growth inhibition test on microalgae (72 h) and acute immobilization test on instar I and II of Artemia nauplii (48 h) were conducted following, OECD 201 and ISO/TS 20787, respectively. The toxicity of ZIF-8 NPs to both species was time- and concentration-dependent. The 72-h median inhibitory concentration (IC50) of ZIF-8 NPs for N. oculata based on average specific growth rate and yield were calculated as 79.71 ± 8.55 mg L-1 and 51.73 ± 5.16 mg L-1, respectively. Also, the 48-h median effective concentration (EC50) of ZIF-8 NPs on immobilization rate of instar I and II were calculated as 175.09 ± 4.14 mg L-1 and 4.69 ± 0.34 mg L-1, respectively. Moreover, the swimming type of non-immobilized animals was affected by ZIF-8 NPs. These findings provide a good insight into the toxicity of nanoparticulate ZIF-8 to saltwater planktons and also confirm that instar II Artemia is more sensitive than instar I. This study demonstrated that ZIF-8 NPs, despite all their advantages, could have toxic effects on aquatic organisms. More studies are required to assess their potential environmental impact and develop strategies to mitigate their toxicity.