Peronia peronii as a bio-indicator to assess the toxicity of waterpipe tobacco leachates in aquatic and sediment media.

This study was aimed to survey toxicity of waterpipe wastes leachates on Peronia peronii in aquatic and sediment environments as two exposure media. For this, leachates of four tobacco types including burnt traditional tobacco (BTT), fresh traditional tobacco (FTT), burnt fruit-flavored tobacco (BFT) and fresh fruit-flavored tobacco (FFT)) were prepared and used to assess their toxic effects on P. peronei in two aquatic and sediment media. The in-vivo toxic effects of five different concentrations of waterpipe tobacco waste leachates on P. peronii were evaluated. The LC50 values of BTTs leachates to P. peronii were 17.50, 16.05, 11.31 and 9.38 g/L at exposure times of 24, 48, 72 and 96 h, respectively in aquatic media. These values for BFTs leachates were 14.86, 12.38, 9.53 and 7.46 g/L at exposure times of 24, 48, 72 and 96 h, respectively. In the case of sediment media, the LC50 values of BTTs leachates were 15.33, 13.70, 9.09 and 6.70 g/L at exposure times of 24, 48, 72 and 96 h, respectively while these values for BFTs leachates were 12.00, 10.32, 8.20 and 5.65 g/L. Fruit-flavored tobacco leachates had significantly higher toxicity than traditional tobacco leachates for P. peronii. The findings also showed significant differences between the LC50 values of different leachates in different media of water and sediment. The results demonstrated that even small amount of tobacco waste (~ 5 to 6 g/L) can lead to P. peronii mortality and may also pose a hazard to other aquatic and benthic organisms. The results obtained from the present study can be used as a baseline data to assess local effects causing from unsafe disposal of post-consumption tobacco waste in beach areas. In addition, these findings can lead to encouraging decision-makers to focus more on the types of tobacco waste in the municipal solid waste management system and to implement a source separation process for these wastes.

Expression of Recombinant Stonustoxin Alpha Subunit and Preparation of polyclonal antiserum for Stonustoxin Neutralization Studies.

Stonustoxin (SNTX) is a lethal protein found in stonefish venom, responsible for many of the symptoms associated with stonefish envenomation. To counter stonefish venom challenges, antivenom is a well-established and effective solution. In this study, we aimed to produce the recombinant alpha subunit protein of Stonustoxin from Synanceia horrida and prepare antibodies against it The SNTXα gene sequence was optimized for E. coli BL21 (DE3) expression and cloned into the pET17b vector. Following purification, the recombinant protein was subcutaneously injected into rabbits, and antibodies were extracted from rabbit´s serum using a G protein column As a result of codon optimization, the codon adaptation index for the SNTXα cassette increased to 0.94. SDS-PAGE analysis validated the expression of SNTXα, with a band observed at 73.5 kDa with a yield of 60 mg/l. ELISA results demonstrated rabbits antibody titers were detectable up to a 1:256,000 dilution. The isolated antibody from rabbit´s serum exhibited a concentration of 1.5 mg/ml, and its sensitivity allowed the detection of a minimum protein concentration of 9.7 ng. In the neutralization assay the purified antibody against SNTXα protected mice challenged with 2 LD50. In conclusion, our study successfully expressed the alpha subunit of Stonustoxin in a prokaryotic host, enabling the production of antibodies for potential use in developing stonefish antivenom.

Antioxidant and anticholinesterase properties of Echinometra mathaei and Ophiocoma erinaceus venoms from the Persian Gulf.

Introduction: The Persian Gulf is home to a diverse range of marine life, including various species of fish, crustaceans, mollusks, and echinoderms. This study investigates the potential therapeutic properties of venoms from echinoderms in the Persian Gulf, specifically their ability to inhibit cholinesterases (Acetylcholinesterase and butyrylcholinesterase) and act as antioxidants. Methods: Four venoms from two echinoderm species, including the spine, gonad, and coelomic fluids of sea urchins, as well as brittle star venoms, were analyzed using various methods, including LD50 determination, protein analysis, antioxidant assays, GC-MS for secondary metabolite identification, and molecular docking simulations. Results and discussion: The study's results revealed the LD50 of the samples as follows: 2.231 ± 0.09, 1.03 ± 0.05, 1.12 ± 0.13, and 6.04 ± 0.13 mg/mL, respectively. Additionally, the protein levels were 44.037 ± 0.002, 74.223 ± 0.025, 469.97 ± 0.02, and 104.407 ± 0.025 µg/mL, respectively. SDS-PAGE and total protein studies indicated that at least part of the venom was proteinaceous. Furthermore, the study found that the brittle star samples exhibited significantly higher antioxidant activity compared to other samples, including the standard ascorbic acid, at all tested concentrations. GC-MS analysis identified 12, 23, 21, and 25 compounds in the samples, respectively. These compounds had distinct chemical and bioactive structures, including alkaloids, terpenes, and steroids. Conclusion: These venoms displayed strong cholinesterase inhibitory and antioxidant activities, likely attributed to their protein content and the presence of alkaloids, terpenes, and steroids. Notably, the alkaloid compound C 7 was identified as a promising candidate for further research in Alzheimer's disease therapy. In conclusion, echinoderms in the Persian Gulf may hold significant potential for discovering novel therapeutic agents.

Acetylcholinesterase inhibitory activity of a neurosteroidal alkaloid from the upside-down jellyfish Cassiopea andromeda venom

Abstract Natural compounds from marine organisms have been rarely studied for their acetylcholinesterase inhibitory activities. The aim of this study was to isolate novel compounds with antiAChE activity from the venom of upside-down jellyfish Cassiopea andromeda Forskål, 1775. The compounds of the fractionated venom on gel filtration chromatography were identified by analyzing gas chromatography-mass spectroscopy data. The structure of the isolated compound that showed the most potent antiAChE activity in a docking study was elucidated by different spectral data, including 1H NMR and 13C NMR. Three compounds, including a neurosteroidal alkaloid androtoxin B, were identified from two venom fractions. This neurosteroidal alkaloid showed strong acetylcholinesterase inhibitory activity (IC50 2.24 ± 0.1 µM) compared with the reference standard, galantamine. The results obtained by a docking study demonstrated that Androtoxin B had close contact with two of the three amino acid residues of the catalytic triad of acetylcholinesterase gorge and was accommodated within a peripheral hydrophobic pocket composed of numerous aromatic site chains. In conclusion, the isolated neurosteroidal alkaloid from Cassiopea andromeda was a potent antiAChE agent with strong binding to both the catalytic and peripheral sites of acetylcholinesterase that correlated well with the experimental data. Further studies are required to determine whether androtoxin B could be a potential treatment for Alzheimer's disease.