Acute Toxicity Assay Research Articles

Ferrate(VI)/percarbonate for the oxidation of micropollutants: Interactive activation and release of low-concentration hydrogen peroxide for efficient electron utilization

A novel "ferrate/percarbonate (Fe(VI)/SPC) co-oxidation process" was used to treat ciprofloxacin (CIP) and various micropollutants (MPs), which owned better performance than mixture of Fe(VI), Na2CO3 and H2O2. The mechanism investigation found that the low-concentration H2O2 (1–2 µM) released by SPC can promote the high-valent iron intermediates (Fe(IV)/Fe(V)) of Fe(VI) to the MP oxidation, and Fe(VI) products can also activate SPC to produce hydroxyl radical (·OH). The interactive activation of Fe(VI) and SPC was realized, which retained the high selectivity of Fe(VI) to electron-rich pollutants, and also made up the oxidation of electron-deficient pollutants through •OH, improving the degradation effect of various MPs by 20–30%, and the rate constant was increased by 1 to 3 times. Moreover, non-purgeable organic carbon (NPOC) determination confirmed that •OH participation reduced the NPOC value of CIP from 5.43 mg/L to 4.37 mg/L. The transformation pathway of CIP showed that Fe(VI)/SPC resulted in more hydroxylation intermediates of CIP than Fe(VI) alone. Acute toxicity assays found that the photoinhibition rate of CIP treated with Fe(VI) alone was 14.5%, while the sample treated with Fe(VI)/SPC showed no significant photoinhibition effect, which proved that the new process had good detoxification properties for CIP.

Effects of pyroligneous acid on acute, chronic, and cyto-genotoxicity to earthworms (Eisenia fetida)

The pyroligneous acid (PA), or wood vinegar, is a byproduct of wood carbonization during the slow pyrolysis process. PA is recognized globally as a safe compound for agriculture due to its various beneficial properties, such as antioxidant, antibacterial, antifungal, and termiticidal properties. However, the impact of different PA concentrations on beneficial soil organisms, such as earthworms has not been investigated. The present study aims to understand the effects of different PA concentrations on earthworm Eisenia fetida. The earthworms were exposed to nine different concentrations of PA in soils, including their control. The acute toxicity assay was performed after 14 days of exposure, and the chronic toxicity assay was performed up to 8 weeks after exposure. The results from the acute toxicity assay demonstrated no significant effect on earthworm mortality. The chronic toxicity assay showed that lower PA concentrations (0.01–0.2% of weight/weight PA in soil) promoted cocoon and juvenile production in soils, whereas higher PA concentrations (0.5 and 1%) had a negative effect. These findings highlight the potential of PA to enhance soil fertility at lower concentrations, up to 0.2%, by stimulating worm activity and subsequent manure production. The outcomes of this study have significant implications for the careful management of PA concentrations within agricultural operations.

Novel anti-neuroinflammatory pyranone-carbamate derivatives as selective butyrylcholinesterase inhibitors for treating Alzheimer’s disease

Butyrylcholinesterase (BuChE) and neuroinflammation have recently emerged as promising therapeutic directions for Alzheimer’s disease (AD). Herein, we synthesised 19 novel pyranone-carbamate derivatives and evaluated their activities against cholinesterases and neuroinflammation. The optimal compound 7p exhibited balanced BuChE inhibitory activity (eqBuChE IC50 = 4.68 nM; huBuChE IC50 = 9.12 nM) and anti-neuroinflammatory activity (NO inhibition = 28.82% at 10 μM, comparable to hydrocortisone). Enzyme kinetic and docking studies confirmed compound 7p was a mix-type BuChE inhibitor. Additionally, compound 7p displayed favourable drug-likeness properties in silico prediction, and exhibited high BBB permeability in the PAMPA-BBB assay. Compound 7p had good safety in vivo as verified by an acute toxicity assay (LD50 > 1000 mg/kg). Most importantly, compound 7p effectively mitigated cognitive and memory impairments in the scopolamine-induced mouse model, showing comparable effects to Rivastigmine. Therefore, we envisioned that compound 7p could serve as a promising lead compound for treating AD.

An appraisal of traditional knowledge of plant poisoning of livestock and its validation through acute toxicity assay in rats.

Background: Kashmir Himalaya hosts the most diverse and rich flora in the world, which serves as grazing land for millions of small ruminants in the area. While most plant species are beneficial, some can be poisonous, causing economic losses and animal health issues for livestock. Consequently, this study is the first comprehensive report on the traditional phyto-toxicological knowledge in District Muzaffarabad and the assessment of its authenticity through experimental studies in rats. Methods: The data regarding traditional knowledge was gathered from 70 key respondents through semi-structured interviews, which was quantitatively analyzed and authenticated through plant extract testing on Wistar female rats and comparison with published resources. Results: A total of 46 poisonous plant species belonging to 23 families and 38 genera were reported to be poisonous in the study area. Results revealed that leaves were the most toxic plant parts (24 species, 52.1%), followed by the whole plant (18 species, 39.1%), stem (17 species, 36.9%), and seeds (10 species, 21.7%). At the organ level, liver as most susceptible affected by 13 species (28.2%), followed by the gastrointestinal tract (15 species, 32.6%), nervous system (13 species, 8.2%), dermis (8 species, 17.3%), renal (7 species, 15.2%), respiratory (4 species, 8.7%), cardiovascular system (3 species, 6.5%), and reproductive system (2 species, 4.3%). The poisonous plant species with high Relative frequency citation (RFC) and fidelity level (FL) were Nerium oleander (RFC, 0.6; FL, 100), Lantana camara (RFC, 0.6; FL, 100), and Ricinus communis (RFC, 0.6; FL, 100). Experimental assessment of acute toxicity assay in rats revealed that Nerium oleander was the most toxic plant with LD50 of (4,000mg/kg), trailed by Ricinus communis (4,200mg/kg), L. camara (4,500mg/kg), and Datura stramonium (4,700mg/kg); however, other plants showed moderate to mild toxicity. The major clinical observations were anorexia, piloerection, dyspnea, salivation, tachypnea, constipation, diarrhea, tremor, itchiness, and dullness. Conclusion: This study showed that numerous poisonous plants pose a significant risk to the livestock industry within Himalayan territory, leading to substantial economic losses. Consequently, it is of utmost importance to conduct further comprehensive studies on the phytotoxicity of plants.

Involvement of TNFα, IL-1β, COX-2 and NO in the anti-inflammatory activity of Tamarix aphylla in Wistar albino rats: an in-vivo and in-vitro study

BackgroundWith the emergence of many side effects from synthetic drugs, there is an urgent need to find a natural alternative to these products. Therefore, our primary aim was to evaluate the anti-inflammatory activity of Tamarix aphylla (TA) and investigate the potential mechanism underlying this action.MethodsInitially, to ensure the safety of the extract and for dose selection, we performed an acute oral toxicity Assay through the oral administration of graded doses up to 4 g\\kg in Wistar rats. then, we used the carrageenan-induced edema model to elucidate the anti-inflammatory activity. Using specific ELISA kits, we measured the levels of TNF-α, IL-1β, COX-2 and NO inside the inflamed paw tissue. Finally, for the in-vitro anti-inflammatory experiment, we used the erythrocyte membrane stability test.ResultsBased on the acute oral toxicity assay, T. aphylla was considered generally safe and three different doses of 100, 200, and 400 mg/kg were chosen for further experiments. Additionally, TA expressed a significant (P < 0.05) anti-inflammatory activity, showing the maximum inhibition percentage at the fifth hour of measurement at 53.47% and 70.06%, at doses of 200 and 400 mg/kg respectively, compared to 63.81% for the standard drug. Similarly, we found that TA effectively reduced the levels of TNF-α and IL-1β at all tested doses (100-200-400 mg/kg) to a greater extent than the standard drug. Moreover, at 400 mg/kg, TA was able to significantly lower the levels of COX-2 and NO inside the inflamed tissue to a level comparable (P < 0.05) with that measured inside the paw tissue of normal rats. Finally, Tamarix aphylla at 100, 200 and 400 mg/kg doses significantly (P < 0.05) inhibited the heat-induced hemolysis of RBCs membrane by 67.78, 74.82 and 82.08%, respectively, compared to 83.89% produced by Aspirin.ConclusionT. aphylla produced a significant (P < 0.05) anti-inflammatory activity compared to the standard drugs either through the reduction of pro-inflammatory mediators or the protection of the lysosomal membrane.

Synthesis and Characterization of Mesoporous Silica Nanoparticles Loaded with P-Cymene against Rice Bacterial Blight

Mesoporous silica nanoparticles (MSNs) can be used as carrier materials for the controlled release of pesticides while reducing their negative environmental impact. In this study, we screened an active ingredient, p-cymene (PC), with an excellent inhibitory effect on rice bacterial blight. Subsequently, the PC was successfully loaded onto MSNs via physisorption (PC@MSNs). PC@MSNs, characterized by a regular spherical shape, smooth surface, and an MSN average size of 262.9 nm, achieved an 8.6% drug loading capacity. The release kinetics of the PC from the PC@MSNs demonstrated a sustained release (288 h) pattern influenced by drug diffusion. The efficacy of the PC@MSNs against Xanthomonas oryzae pv. Oryzae paralleled those of PC. Acute toxicity assays revealed that the PC@MSNs were less toxic to aquatic life (LC50 = 257.867 mg/L) and that the formulation showed no adverse effects on rice seedling growth. In summary, these results suggest that PC@MSNs can broaden PC’s scope of application in managing rice diseases.

Spider venom neurotoxin based bioinsecticides: A novel bioactive for the control of the Asian citrus psyllid Diaphorina citri (Hemiptera)

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/κ-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC50) derived from dose-response artificial diet assays of 27, 20 and 52 μM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies.

In Vivo antidiarrheal effect and phytochemical characterization of Plectranthus barbatus Andrews

Diarrheal infections remain a public health problem. The mainstays of pharmacological therapy for infectious diarrhea include probiotics, antibacterial, and intestinal adsorbents. Nevertheless, these clinical treatments are not devoid of shortcomings including prohibitive costs and adverse effects. Medicinal plants including Plectranthus barbatus(P. barbatus) have folkloric remedies against diarrhea. However, there is paucity of knowledge to scientifically validate the efficacy of P. barbatus on diarrheal infections. This study was undertaken to ascertain antidiarrheal efficacy, bioactive composition, and toxicity profiles of P. barbatus extracts. Antidiarrheal activity and acute toxicity were carried out on Swiss albino mice. Quantitative phytocompound analysis was evaluated using liquid chromatography-mass spectrometry(LCMS). Results indicated that P. barbatus extract has antidiarrheal activity whereby it prolonged the start of diarrhea, causing a decline in the occurrence of wet feces and intestinal transit significantly. Additionally, the extract reduced the accumulation of intraluminal fluid resulting in the decrease in distension, intestinal overload, and water content in the fecal drops. Acute toxicity assay on mice showed that P. barbatus extract was non-toxic at the dosage level of 2000mg/kgbw(milligram/kilogram body weight). LCMS analysis detected presence of phytocompounds associated with antidiarrheal effects including forskolin, gallic, kaempferol, and quercetin. Findings from the current study offer a scientific validation for the folkloric utilization of P. barbatus in the management of diarrhea.

Effect of Nickel-Aluminum Trioxide/Titanium Dioxide Nanocomposites on Photo-oxidation of Olive Mill Wastewater

In this study, the magnetic nickel (Ni) doped aluminium trioxide (aluminium oxide or alumina, Al2 O3 ) based titanium dioxide (TiO2 ) [Ni-Al2 O3 /TiO2 ] nanocomposites (NCs) was used for the photocatalytic oxidation (photo-oxidation) of pollutant parameters {chemical oxygen demand (COD) components [CODtotal, CODdis, CODinert]}, toxic polyphenols [catechol, 3-hydroxybenzoic acid, tyrosol, 4-hydroxybenzoic acid, 4-hydroxyphenylacetic acid, 3-hydroxyphenylpropionic acid, 4-hydroxyphenylpropionic acid, 3,4-dihydroxyphenylethanol, 3,4-dihydroxyphenylacetic acid], and toxic polyaromatics [aniline, 4–nitroaniline, o–toluidine, o-anisidine, benzene, nitrobenzene, ethylbenzene, 3,6-bis(dimethylamino)durene, benzidine, dimethylaniline, 3,3–dichlorobenzidine]} from the olive mill effluent wastewaters (OMW), at different mass ratios of Al2 O3 , TiO2 and Ni (1%/5%/10%; 10%/1%/5% and 1%/10%/5%), at increasing photooxidation times (10, 30, 60, 100 and 120 min), at different Ni/Al2 O3 /TiO2 photocatalyst concentrations (50, 250, 500 and 1000 mg/l), pH values (4.0-7.0-9.0 and 10.0) and temperatures (15°C, 25°C, 50°C and 80°C), under 500 W ultraviolet visible (UV-vis) and 50 W sun lights irradiations, respectively. The acute toxicity assays were operated with Microtox (Aliivibrio fischeri also called Vibrio fischeri) and Daphnia magna acute toxicity tests. The significance of the correlations between data of all experimental samples were determined using the Analysis of Variance (ANOVA) test statistics. Under the optimized conditions, the maximum CODdis, total phenol and total aromatic amines (TAAs) photooxidation yields were 98%, 88%, 94%, respectively, at pH=9.0, at 500 mg/l Ni/Al2 O3 / TiO2 NCs, under 500 W UV-vis light, after 100 min photooxidation time, at 50°C, respectively. The photooxidation yields in OMW under sun light was lower than the photooxidation yields in the OMW under UV-vis light. 94.44% maximum Microtox acute toxicity yield was found in Ni/Al2 O3 /TiO2 NCs=500 mg/l after 150 min photooxidation time, at 60°C. 90% maximum Daphnia magna acute toxicity removal was obtained in Ni/Al2 O3 /TiO2 NCs=500 mg/l after 150 min photooxidation time, at 60o C. Microtox acute toxicity test was more sensitive than Daphnia magna acute toxicity assay

Blood cell alterations in Colossoma macropomum juveniles caused by silver nanoparticles.

This study evaluated the median lethal concentration of silver nanoparticles and their effects in fish tambaqui Colossoma macropomum. Therefore, an acute toxicity assay was carried out in completely randomized design evaluating six different concentrations of silver nanoparticles on blood parameters of tambaqui. The silver nanoparticles were produced by chemical reduction with polyvinyl alcohol (AgNP-PVA). The lethal concentration 50% (LC50) was estimated using probit regression. The blood was collected, analyzed and the data were submitted to T-test (dying x surviving fish) and Tukey test (surviving fish). An increase in glucose, hematocrit, total plasma protein, hemoglobin, erythrocytes, leukocytes, monocytes, and neutrophils as well as reduced MCV (mean corpuscular volume) in dying fish compared to surviving fish were observed. Survived fish exposed to 187.5 µg/L showed an increase in hematocrit, MCV, and MCH and a reduction in erythrocytes, total numbers of leukocyte, thrombocyte, lymphocyte, and neutrophil. The fish exposed to concentrations below 125 µg/L, had returned the blood parameter to baselines compared to control. The estimated LC50 was 165.09 µg/L and was classified as highly toxic for the fish tambaqui. In higher concentrations, it causes an acute respiratory toxicity, but in concentrations below 125 µg/L, the fish can adapt to the stressing agent.

Toxicological Studies and Antibacterial Efficacy of Sorghum bicolor Fermented Liquor Extracts of Bambusa tuldoides cv. ventricosa Leaf against Salmonella typhi

Abstract Background: Bamboo leaf extracted with steep liquor from fermented cereal grains has been used as an ethnomedicine for the treatment of severe typhoid fever in Africa without the proper documentation of its efficacy and side effects. Aim: This study embarks on the evaluation of the toxicity and pharmacological safety profile of fermented Sorghum bicolor liquor extract of Bambusa tuldoides cv. ventricosa leaf as an ethnomedicine against Salmonella typhi infection. Settings and Design: Reconstituted concentrates of various fermented extracts were used for the minimum inhibitory concentration (MIC) assay. Acute toxicity assay comprised two phases. The bioassay constitutes a total of 25 albino mice randomly distributed into 5 test groups. Materials and Methods: Steep liquor from fermented S. bicolor seeds served as the extracting solvent for the leaf of B. tuldoides using Soxhlet apparatus. The determination of both the sensitivity test and MIC assay used different levels. Extracts were orally administered for acute toxicity and dosage determination studies. Extracts were administered at concentrations 25, 50, and 100 mg/mL per day for the bioassays. Application of one-way analysis of variance was used for the determination of the statistical significance of the variations at 0.05 and 0.01 levels. Results and Conclusions: The average zones of inhibition were between 15.00 ± 2.34 and 20.00 ± 4.64 mm, and MIC was 12.5 mg/mL for the growth of S. typhi. The extract administered was found to be safe up to 5000 mg/kg body weight dosage. The agglutination result showed a concentration-dependent effectiveness of fermented liquor extract against S. typhi. Therefore, the bamboo leaf extract is efficient for the treatment of S. typhi infection.

Acute Toxicity Assays with Adult Coral Fragments: A Method for Standardization.

Coral reefs are globally declining due to various anthropogenic stressors. Amongst those, chemical pollutants, such as pesticides from agricultural runoff, sewage or an overabundance of personal care products in coastal waters due to intense tourism, may be considered as a local stressor for reef-building corals. The extent to which such chemicals exhibit toxic effects towards corals at environmentally relevant concentrations is currently controversially discussed and existing studies are often based on varying and sometimes deficient test methods. To address this uncertainty, we adapted available methods into a reliable and comprehensive acute coral toxicity test method for the reef-building coral Montipora digitata. The toxicities of the four substances benzophenone-3 (BP-3), Diuron (DCMU), copper (Cu2+ as CuCl2, positive control) and dimethylformamide (DMF, solvent) were assessed in a 96 h semi-static test design. Endpoints such as maximum quantum yield, bleaching, tissue loss and mortality were evaluated with respect to their suitability for regulatory purposes. Overall, the endpoints bleaching and mortality yielded sensitive and robust results for the four tested substances. As the test method follows the principles of internationally standardized testing methods (ISO, OECD), it can be considered suitable for further validation and standardization. Once validated, a standardized test method will help to obtain reproducible toxicity results useful for marine hazard and risk assessment and regulatory decision making.

Toxicity Evaluation and Controlled-Release of Curcumin-Loaded Amphiphilic Poly-N-vinylpyrrolidone Nanoparticles: In Vitro and In Vivo Models.

Curcumin attracts huge attention because of its biological properties: it is antiproliferative, antioxidant, anti-inflammatory, immunomodulatory and so on. However, its usage has been limited by poor water solubility and low bioavailability. Herein, to solve these problems, we developed curcumin-loaded nanoparticles based on end-capped amphiphilic poly(N-vinylpyrrolidone). Nanoparticles were obtained using the solvent evaporation method and were characterized by dynamic and electrophoretic light scattering, transmission electron (TEM) and atomic force (AFM) microscopy. The average particle size was 200 nm, and the ζ-potential was -4 mV. Curcumin-release studies showed that nanoparticles are stable in aqueous solutions. An in vitro release study showed prolonged action in gastric, intestinal and colonic fluids, consistently, and in PBS. In vitro studies on epidermoid carcinoma and human embryonic kidney cells showed that the cells absorbed more curcumin in nanoparticles compared to free curcumin. Nanoparticles are safe for healthy cells and show high cytotoxicity for glioblastoma cells in cytotoxicity studies in vitro. The median lethal dose was determined in an acute toxicity assay on zebrafish and was 23 μM. Overall, the curcumin-loaded nanoparticles seem promising for cancer treatment.

Rapid development of increased neonicotinoid tolerance in non-target freshwater amphipods

The comprehensive assessment of the long-term impacts of constant exposure to pollutants on wildlife populations remains a relatively unexplored area of ecological risk assessment. Empirical evidence to suggest that multigenerational exposure affects the susceptibility of organisms is scarce, and the underlying mechanisms in the natural environment have yet to be fully understood. In this study, we first examined the arthropod candidate species, Gammarus roeselii that – unlike closely related species – commonly occurs in many contaminated river systems of Central Europe. This makes it a suitable study organism to investigate the development of tolerances and phenotypic adaptations along pollution gradients. In a 96-h acute toxicity assay with the neonicotinoid thiacloprid, we indeed observed a successive increase in tolerance in populations coming from contaminated regions. This was accompanied by a certain phenotypic change, with increased investment into reproduction. To address the question of whether these changes are plastic or emerged from longer lasting evolutionary processes, we conducted a multigeneration experiment in the second part of our study. Here, we used closely-related Hyalella azteca and pre-exposed them for multiple generations to sublethal concentrations of thiacloprid in a semi-static design (one week renewal of media containing 0.1 or 1.0 µg/L thiacloprid). The pre-exposed individuals were then used in acute toxicity assays to see how quickly such adaptive responses can develop. Over only two generations, the tolerance to the neonicotinoid almost doubled, suggesting developmental plasticity as a plausible mechanism for the rapid adaptive response to strong selection factors such as neonicotinoid insecticides. It remains to be discovered whether the plasticity of rapidly developed tolerance is species-specific and explains why closely related species – which may not have comparable adaptive response capabilities – disappear in polluted habitats. Overall, our findings highlight the neglected role of developmental plasticity during short- and long-term exposure of natural populations to pollution. Moreover, our results show that even pollutant levels seven times lower than concentrations found in the study region have a clear impact on the developmental trajectories of non-target species.

In vitro and in vivo antimicrobial effects of domiphen combined with itraconazole against Aspergillus fumigatus

Aspergillus fumigatus, a prevalent saprophytic fungus in the atmosphere, is known to rapidly induce severe invasive aspergillosis (IA) upon inhalation of its conidia by humans or animals. The mortality rate associated with IA exceeds 50%. The misuse of antifungal agents has contributed to the emergence of numerous highly pathogenic drug-resistant strains of A. fumigatus. Our study found that the combination of domiphen and itraconazole had sound synergistic antimicrobial effects against wild-type and itraconazole-resistant A. fumigatus in vivo and in vitro through MIC, FIC, plate inoculation, growth curve experiments, and Galleria mellonella infection model. Drug cytotoxicity and pharmacological tests for acute toxicity assays demonstrated that both itraconazole and domiphen showed minimal cytotoxicity and good biocompatibility. The transcriptome sequencing experiment demonstrated that domiphen exerted a suppressive effect on the expression of various genes, including those involved in drug efflux, redox regulation, and cellular membrane and cell wall remodeling. The present investigation explores the synergistic antimicrobial mechanisms of domiphen and itraconazole, encompassing three key aspects: (i) domiphen inhibited the efflux of itraconazole by reducing the expression of drug efflux-related genes, (ii) the combination has good ability to disrupt the cell membrane and cell wall, (iii) the combination also can remove biofilm more effectively. In summary, the utilization of domiphen as a synergist of itraconazole exhibited disruptive effects on the biofilm, cell wall, and cell membrane of A. fumigatus. This subsequently led to a modified distribution of itraconazole within the fungal organism, ultimately resulting in enhanced antifungal efficacy. The results of this study may provide a new therapeutic strategy for the treatment of IA caused by drug-resistant A. fumigatus.

Quality assessment and evaluation of the aphrodisiac property and toxicity profile of a Ghanaian herbal male vitality booster

BackgroundMist Campa-T (MCT) is a mono-herbal formulation has gained popularity in Ghana for its acclaimed effectiveness in improving sexual function in men. Its main active ingredient is Thoningia sanguinea, a plant known for its aphrodisiac property in folk medicine. This research focused on investigating the aphrodisiac effect of (MCT) and its toxicological profile. MethodsThe effect of MCT on sexual function was investigated by the mounting and mating frequency assays followed by serum testosterone and sperm analysis. The toxicological assessment was performed by the acute and sub-acute toxicity assays. Microbial load and elemental/heavy metal content analysis of the product was ascertained. ResultsMCT (250, 500, 1000 mg/kg/day) exhibited significant (P ≤ 0.0001) increase in mounting and mating frequencies, in male rats. There was a significant (P ≤ 0.0001) rise in testosterone level for the MCT-treated rats. The LD50 of Mist Campa-T was found to be above 2000 mg/kg bodyweight. There was no significant variation (P > 0.05) in haematological indices as well as renal or hepatic enzymes in the treated groups compared to the untreated group after 28 days of treatment with MCT. There was a notable increase (P < 0.01) in haemoglobin level of rats treated with MCT. Elemental and heavy metal content as well as microbial load were all within the range of permissible limits. Phytochemical screening of MCT revealed the presence of saponins, alkaloids, triterpenoids, sterols, reducing sugars and tannins. ConclusionsThe overall results of this study have proven that Mist Campa-T is fairly safe and possesses aphrodisiac effect possibly due to its ability to increase serum testosterone level.

Antibiofouling activity of 1-hexadecyl-3-methylimidazolium chloride against Amphora sp. BARC 104, a fouling diatom isolated from back waters of Kalpakkam

1-Hexadecyl-3-methylimidazolium chloride (C16MimCl), an alkylimidazolium ionic liquid (IL) with a long alkyl side chain (-hexadecyl group) is attractive for antimicrobial applications. However, there are limited studies on the antifouling efficacy of ILs using biofouling organisms especially diatoms. In this study, the antifouling activity of C16MimCl was determined against Amphora sp. BARC 104, a dominant fouling diatom isolated from Kalpakkam coastal waters. Growth of the diatom was inhibited in the presence of IL at varied concentrations starting from 0.15 μM C16MimCl. A complete inhibition in the growth was observed in the presence of 2.5 μM C16MimCl. Adhesion and biofilm formation by Amphora sp. was strongly inhibited at sub-micromolar concentrations of IL. Exposure of diatom cells to IL in acute toxicity assays induced oxidative stress (increased reactive oxygen species generation) and reduced metabolic activity (decreased esterase activity) as revealed by 2,7 -Dichlorodihydrofluorescein diacetate (DCH2FDA) and fluorescein diacetate (FDA) staining, respectively. SYTOX® Green staining and extracellular chlorophyll a measurement revealed a severe membrane damage and leakage of chlorophyll a, respectively, in IL treated diatom cells. These measurements during recovery experiments indicated a permanent damage to cell and thylakoid membranes in the diatom cells. Damage to multiple cellular targets coupled with strong antibiofilm activity suggest potential application of C16MimCl in preparation of antifouling formulations and coatings.

Antinociceptive effect of Nephelium lappaceum L. fruit peel and the participation of nitric oxide, opioid receptors, and ATP-sensitive potassium channels.

Introduction: Nephelium lappaceum L. (Sapindaceae) is a plant known as rambutan. It is used for various purposes in traditional medicine. Objective: We aimed to evaluate the antinociceptive effects of the ethanol extract of the fruit peel of N. lappaceum (EENL), the mechanisms involved in these effects, and the acute toxicity in zebrafish. Methods: We performed chromatography coupled to mass spectrometry, acute toxicity assay in zebrafish, and evaluation in mice submitted to models of nociception and locomotor activity. Results: We identified (epi)-catechin, procyanidin B, and ellagic acid and its derivatives in EENL. We did not find any toxicity in zebrafish embryos incubated with EENL. The locomotor activity of mice submitted to oral pretreatment with EENL was not changed, but it reduced the abdominal constrictions induced by acetic acid, the licking/biting time in both the first and second phase of formalin testing and capsaicin testing, and carrageenan-induced paw mechanical allodynia. Oral pretreatment with EENL increased latency time in the hot plate test. This antinociceptive effect was significantly reversed by naloxone, L-arginine, and glibenclamide respectively showing the participation of opioid receptors, nitric oxide, and KATP channels as mediators of EENL-induced antinociception. Conclusion: EENL causes antinociception with the participation of opioid receptors, nitric oxide, and KATP channels, and is not toxic to zebrafish.

Anthelmintic efficacy of febantel against a monogenean parasite, Gyrodactylus kobayashii

Monogenean parasites pose a significant challenge to aquaculture, leading to adverse effects on fish health and yields. Current anthelmintic treatments for monogeneans have demonstrated limited efficacy and are further complicated by potential issues, which emphasize the necessity for effective and safe therapeutic strategies to manage monogeneans in aquaculture. In this study, in vivo and in vitro anthelmintic activity of febantel against Gyrodactylus kobayashii on goldfish (Carassius auratus), as well as its toxicity to goldfish were evaluated. In vivo assays indicated that febantel exhibited potent anthelmintic activity against G. kobayashii with an EC50 value of 0.03 mg/L and 100 % anthelmintic efficacy at 0.1 mg/L after 48 h of exposure. Moreover, in vivo trials also revealed a notable post-treatment effect of febantel, where infected goldfish transferred to drug-free water after short 6-h exposure could still result in full eradication of the worms, indicating febantel might induce persistent perturbations in parasite physiology. In vitro assays showed a negative correlation between febantel concentrations and the survival of G. kobayashii. However, increasing the febantel concentration to 2.0 mg/L did not result in the complete death of all worms. Oral administration of febantel demonstrated limited anthelmintic activity, with only 49 % efficacy at a dosage of 200 mg/kg body weight daily over five days. Acute toxicity assays revealed the 48-h LC50 value of febantel was 5.47 mg/L, which was 182.23 times higher than the 48-h EC50 value, indicating that febantel has a favorable safety profile. However, febantel exposure potentially interfered with hepatic metabolism and oxidative status, as indicated by variations in SOD, GST, and P450 gene expression. In conclusion, treatment with 0.1 mg/L febantel for 24 h completely eradicated G. kobayashii infection on goldfish, demonstrating febantel’s potent anthelmintic activity. Coupled with its safety profile and extended post-treatment effectiveness, febantel is a promising candidate for controlling Gyrodactylus infections in aquaculture.

A dinoflagellate bloom caused by multiple species of Kareniaceae in the coastal waters of Fujian in June 2022 and its adverse impacts on Brachionus plicatilis and Artemia salina

Recently, dinoflagellate blooms have frequently occurred in the coastal waters of Fujian, East China Sea. In June 2022, a fish-killing bloom of Kareniaceae species occurred in this region. In this study, four species of Kareniaceae, namely, Karenia longicanalis, K. papilionacea, Karlodinium veneficum, and Karl. digitatum were identified from this bloom event based on the results of single-cell PCR and clone libraries, and intraspecies genetic diversity was found in the Karl. veneficum population. The results of acute toxicity assays of the bloom water to two zooplankton species (Brachionus plicatilis and Artemia salina) demonstrated this bloom event strongly inhibited their swimming capacities and survival. The results of this study suggested that the bloom events caused by multiple species of Kareniaceae in the Fujian coastal waters had adverse impacts on the local fishery resources and zooplankton community.