Determination Of Acute Toxicity Research Articles

Determination of acute toxicity and evaluation of the chronic effect of nitrate on compensatory growth of Litopenaeus vannamei reared in a biofloc technology system

Understanding the effect of acute and chronic nitrate stress on Litopenaeus vannamei grown in intensive biofloc technology systems is essential for production optimization. The present study evaluated L. vannamei exposed to nitrate extremes at a salinity of 25 g.L−1 measuring survival and possible recovery through compensatory growth. An initial clear-water lethal test, revealed an LC50–96 h for nitrate of 2789.11 mg.L−1. The nitrate safe level was determined as 278.91 mg.L−1by the Sprague Factor (0.1 of the LC50–96 h). Consequently, a chronic exposure experiment was carried out in a Biofloc Technology System. A 3 × 2 experimental design was applied, with two nitrate concentrations (278.91 mg.L−1 and 139.45 mg.L−1) and three “stress” exposure times (10, 20 and 30 days) followed by 48, 38 and 28 days “recovery” time, respectively. A control, in which the nitrate was maintained below 25% of the calculated safe level was maintained for 58 days. The experiment was divided into two phases: (1) stress and (2) recovery. Survival did not differ among treatments during the experimental period. Shrimp exposed to concentrations of 278.91 mg.L−1 and 139.45 mg.L−1of nitrate over 20 and 30 days exhibited reduced growth, while growth of shrimp exposed 10 days did not differ from the control. After the end of the recovery phase (day 58), no significant differences were found in shrimp weights among treatments. Results indicate L. vannamei presents higher resistance to nitrate, but prolonged exposures (>20 days) to concentrations above 139.45 mg.L−1may negatively affect growth rates. However, when lower nitrate values are re-established, the animals exhibit compensatory growth nullifying significant differences to cohort members maintained at optimal nitrate throughout.

Evaluation of the disinfectant “Enzidez” according to indicators of acute toxicity and irritant effect

Despite the fairly large number of disinfectants on the market, there is no perfect drug, as microorganisms adapt to new antibacterial substances quite quickly. In this regard, recently, enzymatic preparations for the hydrolysis of protein contaminants and the destruction of the glycopeptide matrix of the microbial biofilm have been introduced into disinfectants. Therefore, disinfectants that have a wide spectrum of antimicrobial action, actively remove organic contaminants and affect the biofilm forms of bacteria are considered relevant and promising for development. The purpose of the work was to conduct a toxicological evaluation of the developed disinfectant “Enzidez” according to indicators of acute toxicity and irritant effect. Determination of acute toxicity and irritant effect of the native disinfectant and its 1 % solution was carried out according to generally accepted methods. Studies on establishing the parameters of subacute (acute) toxicity of Enzidez disinfectant on white mice revealed that the working 1.0 % concentration of Enzidez disinfectant did not cause the death of mice when administered intragastrically in a dose of 5000 to 13000 mg/kg. This indicates that a dose of 13,000 mg/kg body weight will be tolerated (LD0) for animals, while the median lethal (LD50) dose will be higher than this amount. According to the classification regarding the harmfulness of substances, the disinfectant in a working concentration of 1.0 % will be considered low-toxic (toxicity class 4).In the pathological autopsy of laboratory mice after administering lethal and working doses of the drug “Enzidez” to them, it was established that the mice died from pulmonary insufficiency due to hyperemia and pulmonary edema. According to the degree of danger, the product belongs to class 4 (low-toxic substances). When a working 1.0 % solution of the disinfectant was injected into the stomach, no visible pathological-anatomical changes were detected in experimental mice after euthanasia, which indicates its low toxicity. In addition, it was found that the native solution of the disinfectant causes slight irritation to the skin of white rabbits, so rubber gloves should be used when preparing working concentrations of the solution. The working 1 % solution of Enzidez, in turn, did not cause an irritating effect. In addition, it was found that the native solution of the disinfectant caused a harmful effect of 9 points on the mucous membrane of the eyes, and the working – 1 % solution did not cause visible changes in the mucous membrane. Therefore, when working with the native disinfectant “Enzidez”, it is necessary to use eye protection – glasses.

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.

Biological Activities of Chamaecyparis lawsoniana (A.Murray bis) Parl. and Thuja plicata Donn ex D.Don Essential Oils: Toxicity, Genotoxicity, Antigenotoxicity, and Antimicrobial Activity

Essential oils (EOs) derived from evergreen conifer trees are recognized as complex sources of agents with various biological activities. In this study, the biological activities of the EOs derived from Chamaecyparis lawsoniana (A.Murray bis) Parl. (CLEO) and Thuja plicata Donn ex D.Don (TPEO) were investigated. The third instar larvae of the fruit fly Drosophila melanogaster were used as a model organism to determine the in vivo toxicity, genotoxicity, and antigenotoxicity of five different concentrations of CLEO and TPEO, ranging from 0.19% to 3%. Artemia salina was used for acute toxicity assessment and determination of LC50 after 24 h and 48 h. The antimicrobial activity of the CLEO and TPEO was tested against fourteen bacterial and two fungal strains using the microdilution method. The larvicidal activity and developmental time of D. melanogaster increased as the concentrations of the EOs rose. CLEO and TPEO produced a dose-dependent increase in DNA damage compared with the negative control. Both oils, at concentrations up to 1.5%, demonstrated the ability to reduce the genotoxic effect induced by ethyl methanesulfonate, with a reduction rate exceeding 60%. CLEO and TPEO were highly toxic against Artemia salina nauplii. The results indicate that the tested EOs act as antimicrobial agents against some pathogenic bacteria and fungi. CLEO and TPEO show promising potential as a source of antimicrobial and antigenotoxic agents and as potential biocides against pest insects and arthropods.

Acute Toxicity Determination and Compound Changing with Chemometric Procedures from Komba-Komba Leaf (Chromolaena odorata L.)

The employing of komba-komba leaves (Chromolaena odorata L.), a medicinal plant that can prevent and treat many ailments, is one example of the expanding use of traditional medicine in the health field. To increase their use as traditional medicine, Komba-komba leaves must have complete information about their safety due to the abundance of secondary metabolite substances they contain. The goal of this work was to classify the extract components and fractions of komba-komba leaves using FTIR spectra and a PCA chemometric technique, as well as to estimate the hazardous potential of komba-komba leaves, total flavonoid and phenolic levels from komba-komba leaves. The BSLT (Brine Shrimp Lethality Test) method was used for acute toxicity testing. The toxicity test results revealed that the LC50 values of the komba-komba leaves (Chromolaena odorata L.) n-hexane fraction, ethyl acetate fraction, and insoluble ethyl acetate fraction had LC50 values 1000 ppm, indicating that the extract and n-hexane fractions were poisonous. The total flavonoid concentration was determined to be 243.4 mgEQ/g in the methanol extract, 380.1 in the n-hexane fraction, 512.8 in the ethyl acetate fraction, and 189 mgEQ/g in the ethyl acetate insoluble fraction. The methanol extract's total phenolic content was 146.3 mgEAG/g, whereas that of the n-hexane, ethyl acetate, and insoluble ethyl acetate fractions was 269.6, 360.9, and 109.3 mgEAG/g, respectively. From the results of the score plot, it can be seen that the PCA analysis was successful in demonstrating group differences between extracts and fractions of komba-komba leaves. Extracts and fractions of C.odorata L. leaves have moderate toxicity due to the presence of flavonoid and phenolic content, making them potential candidates for development as natural antioxidants.

Phytochemical Screening, GCMS Profiling, In Vitro Antioxidant, In Vivo Acute Toxicity, and Hepatoprotective Activity of Cleome simplicifolia Bioactive Metabolites against Paracetamol-Intoxicated Wister Albino Rats

The current study aimed to appraise extracts of Cleome simplicifolia (Cambess.) Hook. f. and Thomson leaves for chemical integrant and biological activities. In this study, different extracts of leaves were estimated for qualitative phytochemical screening, identification of functional groups, mineral content, and phyto-compounds and assessed for in vitro antioxidant and in vivo acute toxicity and hepatoprotective activity antagonistic toward paracetamol-intoxicated Wister albino rats. The results of the qualitative phytochemical assessment of the leaf extracts (acetone, methanol, and distilled water) exhibited the occurrence of useful metabolites. A Fourier transform infrared analysis confirmed the occurrence of O-H, N-H, C=C, S=O, C-O, C-N, C-Cl, and C-Br at 3367.14, 2920.79, 2850.32, 1631.04, 1384.59, 1168.64, 1063.78, 824.78, and 615.25 cm−1 wavelengths, whereas energy-dispersive X-ray showed the existence of carbon, oxygen, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, and calcium elements in the leaf, respectively. Thereafter, a gas chromatography–mass spectroscopy analysis unveiled the diverse volatile compounds in the methanolic leaf extracts, namely n-Heptyl acrylate—18.87%, undecane—17.49%, 2-Propenoic acid, 3-(3,4-dimethoxyphenyl)-, (E)—11.40%, Neophytadiene—11.02%, n-Hexadecanoic acid—10.78%, Glafenin—10.09%, Decane—7.45%, Phytol—6.0%, Benzene, (1-methyldodecyl)—3.48%, and 4-Cyclohexyl-1-butanol—3.41%, respectively. An analysis of in vitro antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay of methanolic leaf extract revealed elevated levels of antioxidant ability at 20 (46.18%), 40 (53.83%), 60 (66.64%), 80 (74.03%), and 100 (85.05%) μg/mL. In addition, in vivo acute toxicity determination proved that the methanolic leaf extract was innocuous and caused no mortality at 72 mg, 78 mg, or 82 mg/kg b.wt. doses. The methanolic leaf extracts’ in vivo hepatoprotective activity against paracetamol revealed significant efficacy at 50 and 100 mg/kg b.wt. via reduction of aspartate transaminase, alanine transaminase, alkaline phosphatase, bilirubin, and cholesterol (serum blood biochemical markers) followed by an enhancement in superoxide dismutase, catalase, and glutathione (liver antioxidants) with lipid peroxidation depletion compared with the normal group rats. From the investigated study, it was concluded that the C. simplicifolia leaf are a potential source for the isolation of biologically active phyto-compounds and have the ability to prevent liver damage by paracetamol induction, where the hepatic restoration ability is indexed to its in vivo and in vitro antioxidant ability, which might be the result of its chemical constituents.

Monograph: Acute Toxicity, Phytochemical Analysis and Ethnomedicinal Study of Aqueous (Leaf and Stem Back) Extracts of three Ethnomedicinal plants (Macaranga hurifolia, Mareya micrantha, and Mallotus oppositifolius) from Ivorian Pharmacopoeia on Rats

Macaranga hurifolia (ZG02), Mallotus oppositifolius (ZG04), and Mareya micrantha (ZG08) are ethnomedicinal plants belong to Euphorbiaceae family Which are frequently used in treating various diseases in Ivory Coast. The aim of this study is to determine the phytochemical composition and safety level of these three plants.
 Phytochemical assays were conducted using tubes following standard methods. Acute toxicity was assessed according to OECD 423 guidelinesThe rats were divided into fifteen groups of three rats each, 4 control groups,4ZG02 groups, 4 ZG04 groups, and 3 ZG08 groups).
 Results of phytochemical analysis revealed that ZG02 contains polyphenols, flavonoids, alkaloids, gallotannins, and saponins. ZG04 contains polyphenols, flavonoids, catechin tannins, saponins, as well as sterols and terpenoids.While ZG08 contains polyphenols, flavonoids, gallotannins, catechin tannins, saponins, as well as sterols and terpenoids.
 Regarding acute toxicity, administration of the aqueous extracts for the determination of acute toxicity of ZG02 and ZG04, did not produce any mortality in the rats for dosages of up to 2000 mg/kg. Thus, the LD50 (lethal dose for 50% of the population) of ZG02 and ZG04 is greater than 2000 mg/kg of body weight. However, the treatment of ZG08 at 300 mg/kg of body weight, caused a modification in the behavior of the test animals, while the treatment at 2000 mg/kg of body weight resulted in the death of all 3 tested ras. The LD50 of ZG08 is equal to 500 mg/kg of body weight.
 In conclusion, the presence of rich active phytochemical, justifying the traditional uses of the plant. ZG02 and ZG04 show no oral toxicity, while ZG08 is toxic through this route

Subcellular responses of fish cells to sewage effluents: Cell line-based and whole-animal based approaches

Acute toxicity determination is essential in the ecological risk assessment. Traditionally, acute toxicity testing requires substantial numbers of animals and uses death as an apical end point which requires large number of experimental animals and takes days to obtain the results. Application of fish cell lines can provide a possible alternative to traditional acute toxicity test. However, cell-based assay may show several orders of magnitude less sensitive than the animal-based results. Some changes in cellular organelles could have the sensitivity in responding to pollutants. For this reason, a cell-based fluorescent assay was developed using rabbitfish fin cells as model and fluorescent probes to visualize the subcellular responses. The subcellular responses under sewage effluents exposure were captured by confocal microscopy. These cellular responses were quantified and several subcellular indexes represented the toxicity. The optimized assay was then used to determine the toxicity of sewage effluents displaying toxicity to aquatic animals. Through visualization of cellular responses, we further screened several cellular indexes including lysosomal number and mitochondrial size which had a good linear relationship with sewage effluents content. Besides, these cellular indexes had a good agreement between in vivo and in vitro results, demonstrating the accuracy of cellular parameters in representing the acute toxicity of sewage effluents. The developed cell-based testing assay presented here has the characteristics of a faster and cheaper method, which does not require complex facilities and large amount of testing samples. The developed assay may be further applied in predicting the acute toxicity to sewage effluents.

Haematinic and Hepatoprotective Properties of Telfairia occidentalis Fruit Mesocarp on Phenylhydrazine-Induced Anaemia in Experimental Rats.

The level and potential of iron contained in fluted pumpkin (Telfairia occidentalis) has been exploited as a blood tonic; however, the potentials of some other parts of the plant are unknown. The effect of T. occidentalis fruit mesocarp (aqueous extract) on phenylhydrazine (PHZ)-induced anaemia in experimental rats was investigated in a bid to determine its curative properties and potential in reversing haemolytic anaemia and protection of liver health. The LD50 of the fruit extract was determined using Lorke's method for the determination of acute toxicity. The study involved oral administration of varying doses of the extract to different groups of rats which were monitored for 24 hours. The test sample did not show any signs of toxicity at doses of 5000 mg/kg b.wt, which is the highest possible recommended dose for toxicity testing. For the evaluation of the effects of the fruit extract on haematological indices and biochemical enzyme markers in anaemic rats, 30 matured albino Wistar rats were used. The rats were divided into five groups of six rats each. Group 1 consisted of normal rats (control group), Group 2 consisted of anaemic untreated rats, and Group 3 consisted of anaemic rats treated with the standard drug Astymin, while Groups 4 and 5 were made up of anaemic rats given the extract at doses of 600 mg/kg b.wt and 1000 mg/kg b.wt, respectively. The fruit extract failed to show any significant effect in improving the haemoglobin (Hb), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphate (ALP) levels in anaemic rats but rather may have contributed to a reduction in Hb levels and an unhealthy increase in serum enzyme levels. This is indicative of the apparent inability of the aqueous extract of the T. occidentalis fruit mesocarp to reverse PHZ-induced haemolytic anaemia and may suggest a possible detrimental effect of high doses of the extract over a prolonged period.

CHARACTERIZATION OF FRACTION CONTAINING BETA ASARONE ISOLATED FROM ACORUS CALAMUS LINN. RHI- ZOMES AND STUDYING THE AMELIORATIVE EFFECT OF JUGLANS REGIA KERNEL OIL ON ITS ANTIEPILEPTIC PO- TENTIAL

Sweet flag (Acorus calamus) has a long history of use in the treatment of a range of diseases, including inflammatory response, chest pain, digestive problems, and neurological disorders. The prime objective of the study is to isolate newer moieties from Acorus calamus (AC) rhizomes and to test their anticonvulsant potential with Juglans Regia Kernel Oil (Walnut Oil). Pharmacognostic standardization of AC rhizomes have been performed as per WHO guidelines of standardization. Methanolic extract of AC rhizomes was used for isolation of active moieties using column chromatography. Further, characterization of isolated moieties has been performed using UV, IR, 1H-NMR, C13- NMR and LCMS data. OECD 423 guidelines have been fol- lowed for the determination of oral acute toxicity. Swiss albino mice(n=6) were used for in-vivo studies. An- ticonvulsant study of isolated and characterized fraction of Beta Asarone was performed using scPTZ in- duced convulsion model. Pharmacognostic standardization of rhizomes showed results that fall within the pharmacopoeial limits. Spectral details of the fraction confirmed the identity as Beta Asarone. Juglans Regia Kernel oil and AC isolated fraction has shown a better ameliorative antiepileptic effect with prolonged time for seizure onset. Percentage protection has also been enhanced as compared to standard drug.

Determination of acute toxicity of sodium pyrithione and its exposure effects on antioxidant enzymes activity, immune status, and histopathological changes in common carp

ABSTRACT This study determined the LC50-24 h value of sodium pyrithione (NaPT) on Cyprinus carpio at 102.7643 µg/L. Then, 60 healthy fish were randomly allocated into 6 exposure groups, each receiving varying levels of NaPT for different durations (control goup = 0% µg/L NaPT for 24 and 96 h; NaPT-10 = 10% of the LC50-24 h dose of NaPT for 24 and 96 h; NaPT-20 = 20% of the LC50-24 h dose of NaPT for 24 and 96 h). As a result, the increase in malondialdehyde (MDA) levels and the decrease in catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities in the gill and liver tissue in both duration and dose groups were found to be statistically significant. In addition, NaPT increased serum tumour necrosis factor (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6) levels in both dose groups for both durations. The results revealed that NaPT exposure caused shortening of gill tissue lamellae and vacuolisation (separation) of the secondary lamellar epithelium. Likewise, NaPT exposure was responsible for vacuolisation and hepatocellular degeneration in liver tissue in hepatocytes. In conclusion, the toxicity study, antioxidant enzyme activities, cytokine immune response, and histopathological results indicate that NaPT has a toxic effect on the carp.

Acute Toxicity Testing and Phytochemical Screening of Hydromethanolic Leaf Extract of Maerua angolensis on Albino Wistar Rats

Maerua angolensis leaves have been used traditionally for the treatment of several ailments which include but not limited to anaemia, jaundice, arthritis, insomnia, liver diseases and neurological disorders. Despite its widespread use and several reported beneficial uses, there is a paucity of data on its toxicity potential. This study was therefore designed to evaluate the phytochemical constituents and acute toxicity potential of hydromethanolic leaf extract of Maerua angolensis on albino wistar rats. Phytochemical screening was carried out using a standard procedure for the identification of phytochemicals as described in the literatures. Acute toxicity determination was done in two phases (using Lorke‟s method). In the first phase, the rats were divided into three groups of three rats each and were administered 10mg/kg, 100mg/kg and 1000mg/kg body weight of the hydromethanolic leaf extract of Maerua angolensis respectively. In the second phase, the rats were divided into three groups of one rat each and were administered 1600mg/kg, 2900mg/kg and 5000mg/kg body weight of the hydromethanolic leaf extract of Maerua angolensis respectively. Phytochemical screening revealed that the hydromethanolic leaf extract of Maerua angolensis contains flavonoids, cardiac glycosides, saponins, tannins and terpenoids. The rats did not show any signs or symptoms of toxicity following the administration of the extract during both phases. Therefore, it could be concluded that Maerua angolensis leaves contain essential constituents needed in the treatment and management of various ailments and are also safe for use as the LD50 was >5000mg/kg supporting its folkloric use in disease management.

Toxicological characteristics of raw milk with different contents of 17β-estradiol

Despite the benefits and biological value of dairy products, they can also be a source of dangerous substances of natural and artificial origin. Such substances include the estrogen hormone 17β-estradiol, an excessive amount of which causes oncological diseases and reproductive system dysfunction. A study was conducted to determine the toxicological evaluation of raw milk with different 17β-estradiol content on the culture of the ciliate Tetrachymena pyriformis. The content of 17β-estradiol was determined by enzyme immunoassay using the RIDASCREEN®17β-őstradiol test system (Art-Biopharm/R-Biopharm, Darmstadt, Germany). During the determination of acute toxicity, under the condition of the content of 17ß-estradiol in the raw milk in the amount from 20.0 to 2500 pg/ml, no changes in motor activity, body shape and inhibition of reproduction of ciliates were observed. At the content of 17ß-estradiol in milk in the range of 5000.0−5500.0 pg/ml, a slowdown in the motor activity of ciliates was observed without changing the nature of the movement. Thus, the amount of 17ß-estradiol in milk greater than 5000.0 pg/ml causes a minor effect on the vital activity and motor activity of Tetrachymena pyriformis ciliates. During 96 hours of the existence of ciliates in milk, chronic toxic effects on cells were not observed for the content of 17ß-estradiol from 20.0 to 2500.0 pg/ml. Addition of 17ß-estradiol to raw milk in the amount of 5000.0 to 5500.0 pg/ml caused a chronic toxic effect on ciliates, as a result of which the total score in all determined indicators increased to 2 points. Thus, raw milk with an amount of 17ß-estradiol from 5000.0 to 5500.0 pg/ml may exhibit some chronic toxic effect on the cells of the ciliated infusoria. It was established that the relative biological value of raw milk with a content of 17ß-estradiol up to 2500.0 pg/ml was from 98.6 to 97.7 %, and in samples of raw milk with the maximum amount of the hormone (5000.0−5500.0 pg/ml) decreased by an average of 10 % to 89.22 %. Therefore, if the amount of 17ß-estradiol in milk is more than 5000.0 mg/ml, a chronic toxic effect on Tetrachymena pyriformis cells is possible.

Effect of castalagin against HSV-1 infection in newborn mice

We tested in vivo anti-herpetic effect of castalagin, an ellagitannin compound, extracted from pedunculate oak (Quercus robur). Previous investigations found that castalagin possesses a strong inhibitory effect in vitro against HSV-1/2 equal to acyclovir (ACV). It is also effective against ACV-resistant mutants and shows a synergistic effect with ACV. We study castalagin’s activity towards HSV-1 infection in newborn mice. Acute toxicity determination in mice showed LD50 value of 295 mg/kg. Prolonged toxicity was also constructed. Castalagin manifested a marked activity against HSV-1 (LD90/0.02 ml) administered in 7-day course at 0.02 ml s.c. doses of 7.5 or 10 mg/kg (PI 57-58%). ACV course demonstrated a marked activity at 20 mg/kg. The selectivity ratio LD50/ED50 (295/7.5) could be accepted as ≥ 33.

Evaluation of the Local Anesthetic Activity, Acute Toxicity, and Structure-Toxicity Relationship in Series of Synthesized 1-Aryltetrahydroisoquinoline Alkaloid Derivatives In Vivo and In Silico.

Isoquinoline alkaloids constitute one of the most common classes of alkaloids that have shown a pronounced role in curing various diseases. Finding ways to reduce the toxicity of these molecules and to increase their therapeutic margin is an urgent matter. Here, a one-step method for the synthesis of a series of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines was performed in 85-98% yield by the Pictet-Spengler reaction. This was accomplished using the reaction between 3,4-dimethoxyphenylethylamine and substituted benzaldehydes boiling in trifluoroacetic acid. Furthermore, 1-(3'-amino-, 4'-aminophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines were obtained in 94% and 97% yield by reduction in 1-(3'-nitro-, 4'-nitrophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines with SnCl2 × 2H2O. The structures of the substances obtained were confirmed by infrared (IR) and nuclear magnetic resonance (1H and 13C NMR) spectra. ADMET/TOPKAT in silico study concluded that the synthesized compounds exhibited acceptable pharmacodynamic and pharmacokinetic properties without carcinogenic or mutagenic potential but with variable hepatotoxicity. The acute toxicity and structure-toxicity relationship (STR) in the series of 20 derivatives of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines (3a-r, 4a, b) was studied via determination of acute toxicity and resorptive action in white mice employing intragastric step-by-step administration. The first compound, 1-phenyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline hydrochloride (3a), showed the highest toxicity with LD50 of 280 mg/kg in contrast to 1-(3'-bromo -4'-hydroxyphenyl)-6,7-methylenedioxy-1,2,3,4-tetrahydroisoquinoline hydrochloride (3e) which proved to be the safest of the compounds studied. Its toxicity was 13.75 times lower than that of the parent compound 3a. All compounds investigated showed high local anesthetic activity on rabbit eyes in the concentrations studied. Only 3r, 3n, and 4a caused eye irritation and redness. All investigated derivatives (except 4b) in 1% concentration were more active than lidocaine, providing longer duration of complete anesthesia. Therefore, based on the obtained results of in silico tests, local anesthesia, and acute toxicity, a conclusion can be drawn that the experimental compounds need further extensive future investigations and possible modifications so that they can act as promising drug candidates.

Evaluation of the Nutritional Value and Acute Toxicity of the Seeds of the Fruit of <i>Annona muricata</i> L. (Sursop) Consumed in Kinshasa

In this paper, the author aimed to determine the nutritional value of soursop (Annona muricata L. fruit) consumed in Kinshasa as well as the study of the acute toxicity of its seeds. The fruit of Annona muricata L. was sampled according to the ISO 7002 standard for agricultural and food products. The selected fruits were ripe, without physical damage. The usual analytical methods allowed the determination of the nutritional value of the fruit pulp of Annona muricata L. The water content was measured by the method of loss of mass on drying. The total amount of ash was determined by incineration in the oven at 550°C. The mineral elements were determined by inductively coupled plasma spectrometry (ICP0). The determination of acute toxicity was carried out on 25 female mice of the NMRI SUISSE species according to OECD 425 guidelines. For 100 grams of fresh material from the fruit pulp, we noted a very high water content of 84% ± 6%. We also note a particularly high amount of carbohydrates with a rate of 12.2% ± 2%. Protein and lipid content were relatively low at 1% ± 0.01% and 0.7% ± 0.3% respectively. The dietary fiber content was 0.8% ± 0.2%. An energy value of 49.3 Kcal per 100 grams of pulp was determined. The LD 50 obtained was 3320 mg/kg, indicating slight toxicity of soursop seeds. The results of this study show that the white pulp of the fruit of Annona muricata L. consumed in Kinshasa is rich in carbohydrates when we compare it to others biomolecules. It also contains dietary fiber and mineral salts making soursop an excellent constituent of a weight loss diet with a low energy intake.

The diverse ways to determine experimental dose in animals 

Acute toxicity is manifested in terms of effects which occur after a single administration or a relatively brief exposure to a substance or mixture. The evidence for acute toxicity is usually obtained from animal testing so acute toxicity is usually characterised in terms of lethality and exposure times used in experimental protocols. Mainly two hazardous classes for acute toxicity are reported that are known as “Acute toxicity” and “STOT-SE (Specific Target Organ Toxicity-Single Exposure)”. This classification is based upon the evident lethality which is commonly reported as LD50/LC50 value. STOT-SE should be considered where there is clear evidence of toxicity to a specific organ, especially when it is observed in the absence of lethality. Once the LD50/LC50 value is determined, then acute toxicity estimate (ATE) could be decided therefore accurate measurement of LD50 is cardinal to understand the dose responses in animal experimentations. Current review entails a diverse method for determination of acute toxicity along with their merits and demerits. Also, it unfolds why three alternative methods i.e., fixed dose procedure (FDP), acute toxicity class (ATC) method and up and down method revealed a wide acceptance from scientific community even though the classical methods were present.

In Silico Conformation of the Drug Colchicine into Tubulin Models and Acute Phytotoxic Activity on Cucumis sativus Radicles

Many tests are used to determine the toxic activity of miscellaneous substances, and those that are simple, fast, and inexpensive are useful for screening compounds with applications in different fields. The Cucumis sativus root growth inhibition test is an example of acute toxicity determinations. On the other hand, colchicine has been used as a herbicide to generate polyploids in plant species finally reaching the environment; for this reason, colchicine could become a point of attention in ecotoxicology. This work established that Cucumis sativus, at the colchicine binding site (CBS) in tubulin, shares 100% similarity with humans. Colchicine was docked on seven Cucumis sativus computational models of the αβ-tubulin heterodimer, allowing us to understand a possible conformation in tubulin to trigger its antimitotic effect. Furthermore, an in vitro phytotoxicity assay of colchicine-treated cucumber radicles indicated a hormetic-type concentration-dependent response with macroscopic changes in radicles and hypocotyl. These results support the highly preserved grade of tubulins in several species, and using microtubule inhibitors could require attention in ecotoxicological issues. The Cucumis sativus root growth test could help evaluate small molecules (colchicine analogs), chiefly by CBS interactions, a known druggable site, still a target in the search for antimitotic compounds.

Developed meloxicam loaded microparticles for colon targeted delivery: Statistical optimization, physicochemical characterization, and in-vivo toxicity study.

The study aimed to fabricate and evaluate Meloxicam (MLX) loaded Hydroxypropyl Methylcellulose (HPMC) microparticles for colon targeting because MLX is a potent analgesic used in the treatment of pain and inflammation associated with colorectal cancer (CRC). Nevertheless, its efficiency is limited by poor solubility and gastrointestinal tracts (GIT) associated side effects. Seventeen formulations of MLX loaded HPMC microparticles were fabricated by the oil-in-oil (O/O)/ emulsion solvent evaporation (ESE) technique. A 3-factor, 3-level Box Behnken (BBD) statistical design was used to estimate the combined effects of the independent variables on the dependent variables (responses), such as the percent yield (R1), the entrapment efficiency (EE) (R2), mean particle size (R3) and in vitro percentage of cumulative drug release (R4). For physicochemical characterization FTIR, XRD, DSC, and SEM analyses were performed. Biocompatibility and non-toxicity were confirmed by in-vivo acute oral toxicity determination. The percentage yield and EE were 65.75-90.71%, and 70.62-88.37%, respectively. However, the mean particle size was 62.89-284.55 μm, and the in vitro cumulative drug release percentage was 74.25-92.64% for 24 hours. FTIR analysis showed that the composition of the particles was completely compatible, while XRD analysis confirmed the crystalline nature of the pure drug and its transition into an amorphous state after formulation. DSC analysis revealed the thermal stability of the formulations. The SEM analysis showed dense spherical particles. The toxicity study in albino rabbits showed no toxicity and was found biocompatible. The histopathological evaluation showed no signs of altered patterns. Results of this study highlighted a standard colonic drug delivery system with the ability to improve patient adherence and reduce GIT drug-associated side effects in CRC treatment.

Acute Venom Toxicity Determinations for Five Iranian Vipers and a Scorpion

Background: Poisoning due to the bites and stings of venomous snakes and scorpions is a neglected public health problem, particularly in rural areas. Poor health facilities and inadequate knowledge of health care personnel are the major factors that result in envenomated human victims not receiving adequate care and medical attention. There is a great need for up-to-date and effective healthcare knowledge and awareness of the potency and lethality of venomous creatures in Iran. Assessment of the potency, acute toxicity, and lethal effects of venomous creatures come from a variety of specific tests, such as the 50% median lethal dose (LD50) and ample animal experimentations. Methods: In the present study, using modified Reed-Muench method, the LD0, LD50, and LD100 values of the venoms from five Iranian vipers and one scorpion were determined. The studied venomous creatures were: Macrovipera lebetina, Vipera albicornuta, Vipera raddei, Caucasicus intemedius agkistrodon, Montivipera latifii, and one scorpion Hemiscorpius lepturus. The venoms were injected in Albino mice (n=204) intraperitoneally, and their toxicities determined. Results: The results revealed that the LD50 values of the above-mentioned creatures were 3.87, 2.05, 1.63, 1.45, 0.84, and 6.33 mg/kg, respectively. Among the vipers, M. latifii had the most potent venom while M. lebetina’s venom had the lowest toxicity. Conclusion: Theoretically, the determined LD50 values provide for objective comparisons of the toxicity among of the venoms. However, comparison becomes complicated due to variations in the venoms’ LD50. Further, based on the venoms’ toxicity levels, H. lepturus’ venom caused the lowest toxicity in the Albino mice.