Subacute Toxicity Study Research Articles

Toxicological evaluation of Sargassum Wightii greville derived fucoidan in wistar rats: Haematological, biochemical and histopathological evidences

ObjectiveThe present study aimed to investigate the acute and subacute toxicity profile of fucoidan obtained from Sargassum wightii Greville, a brown marine algae in order to assess its safety. MethodsFucoidan was isolated from Sargassum wightii Greviile and subjected to FTIR analysis to confirm the functional groups. In acute toxicity study, a single dose of fucoidan (2000 mg/kg) was orally administered to three female rats as per OECD guideline 423. OECD guidelines 407 was adopted for subacute toxicity study. Fucoidan was orally administered to male and female rats at doses of 100, 200 and 400 mg/kg. Hematological, biochemical and histopathological analyses were carried out. ResultsFTIR analysis confirmed the presence of major functional groups. The animals did not show any remarkable toxic signs or mortality in acute toxicity study at single oral administration of fucoidan at the dose of 2000 mg/kg bodyweight. In subacute toxicity, no statistically significant difference in body weight, relative weight of vital organs, food and water intake compared to the control group was observed. Serum glucose and cholesterol showed a statistically significant reduction at all the doses when compared to normal control and the reduction was in a dose dependent manner. There were no other changes observed in biochemical or haematological parameters. Histopathological analysis showed no significant toxic signs at organ levels in treated groups when compared to normal control. ConclusionsBased on the results obtained from acute and subacute toxicity study, fucoidan is considered to be safe in the models tested, which encourages its long term administration for medicinal uses. This study supports the application of fucoidan as a traditional medicine.

Deoxynivalenol and Nivalenol (2nd edition) [Assuring the Maximum Level of Deoxynivalenol in Wheat] (Natural Toxins and Mycotoxins).

Food Safety Commission of Japan (FSCJ) was requested by the Ministry of Health, Labour and Welfare (MHLW) to conduct a risk assessment of deoxynivalenol (DON) to assure the maximal level for DON in foods. Previously, FSCJ had conducted a self-tasking risk assessment of DON and nivalenol (NIV) in 2010. In the current 2nd edition, only the assessment of DON has been revised. Grains contaminated with DON may be also contaminated with its derivatives, namely, 3-acetyldeoxynivalenol (3-Ac-DON), 15-acetyldeoxynivalenol (15-Ac-DON) and deoxynivalenol-3-glucoside (DON-3-glucoside). However, these substances orally ingested are rapidly biotransformed into DON. Therefore, FSCJ identified the total DON (sum of DON and its derivatives) to be assessed. The toxicity of DON was assessed based on the data of absorption-distribution-metabolism-excretion (ADME), acute toxicity, sub-acute toxicity, chronic toxicity, carcinogenicity, reproductive/developmental toxicity, genotoxicity, and immunotoxicity. DON was considered to have no significant genotoxic activity in vivo. The no-observed-adverse-effect level (NOAEL), based on the two-year chronic toxicity study in mice, was set at 0.1 mg DON/kg bw/day. By applying an uncertainty factor (UF) of 100, the TDI for DON was determined as 1 µg /kg bw/day. The average estimated exposure levels of total DON were 0.09 µg /kg bw/day and 0.22 µg/kg bw/day in the whole population and the 1-6 years group, respectively, by the Monte-Carlo method. The average exposure level in Japan was thus judged to be below the TDI, although a chance to exceed the TDI remains possible in the 1-6 years group depending on eating habits and DON contamination. For NIV, the genotoxic property was not able to be assessed due to the limited availability of the experimental data. No carcinogenic effect was observed in a two-year chronic toxicity study in mice, and the International Agency for Research on Cancer (IARC) also classifies Fusarium spp toxins including NIV to be in group 3. FSCJ thus judged that TDI can be set for NIV. Based on various toxicity studies, the TDI of NIV was determined at 0.4 µg/kg bw/day by taking into account of LOAEL 0.4 mg NIV/kg bw/day in a subacute toxicity study in rats with 90-day oral administration and UF of 1,000. The exposure level of NIV in Japan was estimated to be below the TDI. FSCJ judged it’s unlikely that NIV intake leads to adverse health effects in general population.

Subacute oral toxicity of ayurvedic anti-diabetic preparation Jambadyarista in Sprague-Dawley rats

BackgroundJambadyarista is an Ayurvedic polyherbal formulation widely prescribed by Ayurvedic practitioners for the management of diabetes and its associated complications. About 39 companies have marketed this formulation in Bangladesh with consent from the Directorate General of Drug Administration (DGDA). AimThis study investigated the sub-acute oral toxicity of Jambadyarista in the Sprague-Dawley rat model. MethodsThe sub-acute toxicity studies were executed in Sprague-Dawley rats. Jambadyarista formulation was given for 28-days through oral gavage at 10 mL/kg and 20 mL/kg dose to two different groups comprising 6 rats of both sex/groups. Across the experimental period mortality, adverse reactions were closely monitored. After 28-day feeding hematological, biochemical, and relative organ weights were quantified. ResultsNo mortality and/or signs of morbidity were observed for 28-day of repeated-dose sub-acute toxicity. Any pernicious change in body weight, biochemical, and hematological parameters along with relative organ weight were not observed for Jambadyarista. Correlation study among parameters of the renal profile, liver profile, lipid profile also metabolic hormones (T3 and TSH), and enzymes showed the non-toxic rather beneficial role (hypolipidemic) of Jambadyarista in Sprague-Dawley rats. ConclusionJambadyarista preparation did not cause any potential toxic effect in repeated dose subacute toxicity study over Sprague-Dawley rats orally. Therefore, low dose administration of Jambadyarista could have a beneficial effect on diabetes and can be considered safe before the chronic study.

Phytochemical screening, acute and sub-acute toxicity of aqueous extract from a mixture of some recipe of Herniaria glabra L., Opuntia ficus-indica, Zea mays L. and Zizyphus lotus L. used traditionally against renal lithiases

Introduction: Antiurolithiatic plants are used since ancient times, in the form of decoction, infusion, or juice, to eliminate kidney stones and to prevent their recurrence. On the basis of the available ethnopharmacological information, more scientific studies are needed to explore natural and safe antiurolithiatic compounds. Materials and Methods: The present work showed phytochemical screening, acute and sub-acute toxicity of aqueous extract of four plant's mixture: Aerial part (branches, flowers and leaves) of Herniaria glabra, flowers of Opuntia ficus-indica, Zea mays styles and fruits of Zizyphus lotus used traditionally against renal lithiases. Phytochemical screening was performed using qualitative methods. To measure acute toxicity, rats were administered orally by single doses of 0.1, 0.2, 0.5 and 2.0 g/kg body weight (b. w.) of extract of plant's mixture. General behavior adverse effects and mortality were determined during 15 days. For sub-acute study, the aqueous extract was administered at 100 mg/kg b. w. for 28 days to Wistar rats. Animals were monitored daily after an oral administration of aqueous extract of the mixture to detect any changes in b. w., behavior, autonomic profiles, or mortality. Calculation of relative organ weight (ROW) and biochemical analysis were carried out. Results: The acute oral toxicity study showed no mortality and no statistically significant decrease in b. w. and ROW of the treated groups of rats when compared to the control group was observed. In biochemical analysis, there was a significant increase in aspartate aminotransferase, creatinine, urea, and uric acid. Conclusion: This study found that aqueous extract of traditional recipe used against renal lithiasis in Fes-Meknes region containing: Flavonoids, tannins, catechic tannins, coumarins and the glycosides. The results of the acute and sub-acute toxicity studies indicated that the recipe extracts induce a slight hepatotoxic effects in rats treated orally with 100 mg/kg (b. w.).

Dichlobentiazox (Pesticides).

FSCJ conducted the risk assessment of a fungicide, dichlobentiazox (CAS No.957144-77-3), having benzoisothiazole and isothiazole rings, based on results from various studies.The data used in the assessment include fate in animals (rats) and in livestock (goats), fate in plants (paddy rice), residues in crops, subacute toxicity (rats, mice and dogs), chronic toxicity (dogs), carcinogenicity (rats and mice) and other relevant study results. This chemical showed none of carcinogenicity, reproductive toxicity, teratogenicity and genotoxicity. The lowest no-observed-adverse-effect level (NOAEL) obtained in all studies was 5.03 mg/kg bw per day in a two-year chronic toxicity/carcinogenicity study in rats. FSCJ specified an acceptable daily intake (ADI) of 0.05 mg/kg bw per day by applying a safety factor of 100 to the NOAEL.

Toxicological study of aqueous-methanol solvent fraction of methanol extract of Dacryodes edulis leaves

Dacryodes edulis (G. Don) H.J. Lam) is the most popular species under the genus Dacryodes. It is well known for its nutritional and ethno-medicinal uses in South-eastern and South-western Nigeria. This study was aimed to evaluate the toxicity of the aqueous-methanol fraction of crude methanol extract of Dacryodes edulis leaves (AMDE). The test rats were randomized to groups of single oral treatment of AMDE (10−5000 mg/kgbw) for the acute toxicity study. They were monitored for obvious signs of behavioural change and mortality. For the subacute toxicity study, the rats were randomized to three daily treatment groups (of 200, 400 and 600 mg/kgbw of AMDE) for 28 days. The fourth group (control) received 2.5 %v/v DMSO. At the end of the experiment, blood samples were collected for hematology and clinical chemistry evaluation. The histopathology of the livers and kidneys were assessed using the excised organs. The cytotoxicity and genotoxicity of AMDE were also evaluated using Allium cepa model. The result showed that acute administration of AMDE, up to a dose of 5000 mg/kgbw did not result in mortality of the test rats. The observed median lethal dose (LD50) was greater than 5000 mg/kgbw. The subacute oral administration of AMDE for 28 days showed no significant (p > 0.05) effect on liver function, kidney function indices, organ - body weight ratio, but significantly (p < 0.05) decreased erythrocytic indices: red blood cells, haematocrit, and haemoglobin at 600 mg/kgbw. The Allium cepa assay revealed a non-significant reduction in mitotic index and low chromosomal aberrations of the treated groups. In conclusion, the aqueous-methanol solvent fraction of methanol extract of Dacryodes edulis leaves, AMDE is relatively safe. However, there are strong indications that it may contain compounds that are cytotoxic and reduces erythrocytic indices including red blood cells at high doses. Thus, adequate care should be taken in dosing and administering the extract to avert anaemic condition.

Acute and Subacute Toxicity Profiles of the Methanol Extract of Lycopersicon esculentum L. Leaves (Tomato), a Botanical with Promising In Vitro Anticancer Potential.

Lycopersicon esculentum (tomato) is a plant widely used in Africa like food and to solve many health problems. The methanol crude extract of tomato recently demonstrated a good antiproliferative effect on many human cancer cell lines. The aim of this research was to evaluate the acute toxicity and subacute oral toxicity of methanolic extract from leaves of this plant. These toxicities were evaluated based on the OECD (Organization for Economic Cooperation and Development) guidelines. The assay of acute toxicity was performed using a total of 3 female rats, which received a single dose of 5000 mg/kg of methanolic extract via oral gavage. For the subacute toxicity study, 32 Wistar rats (males and females) were used. The groups were treated with three different doses of Lycopersicon esculentum methanolic extract (250, 500, and 1000 mg/kg b.w.) for 28 days and the control group received distilled water. The hematological, biochemical, and histopathological studies were performed after the sacrifice. Single dose of tomato extract caused no toxicity up to a dose of 5000 mg/kg body weight; hence, the median lethal dose (DL50) of leaves of this plant was greater than this value. However, lower toxic effects could be manifested in the long-term treatment at the highest dose (1000 mg/kg) because urea level and total serum proteins significantly increased at a dose of 1000 mg/kg with respect to control. The microscopic observation showed no remarkable pathological changes on all organs in the treated groups compared with the control groups of female and male rats. These results demonstrate that single dose of tomato extract leaves is relatively nontoxic at a dose of 5000 mg/kg b.w. and prolonged use of lower doses (250 and 500 mg/kg) of L. esculentum orally should be encouraged, whereas highest dose (1000 mg/kg) should be avoided.

Acute and Subchronic Oral Safety Profiles of the Sudarshana Suspension

Sudarshana powder (SP) is an Ayurvedic preparation, which contains 53 herbal ingredients along with 50% of Andrographis paniculata and is clinically used with bees honey. This study was aimed to determine the safety profile of the SP, and its novel preparation Sudarshana suspension (SS) on male Wistar rats and tolerance studies were conducted for healthy adult volunteers. Acute and subacute toxicity studies of the SS and hot water extract of SP were assessed in Wistar rats by observing the general behavior, analyzing biochemical and haematological parameters, and pathological observation. Healthy consented adult volunteers (n = 35) of either sex were selected, and tolerance studies of SS were tested by measuring the biochemical and haematological parameters. There were no significant (p > 0.05) changes observed in the treated animals with SS and hot water extract of SP compared with control in body weights, food intake, and water consumption as well as the biochemical and haematological parameters. Histopathological studies revealed no significant (p > 0.05) changes in the liver, heart, and kidney tissues. The experimental results suggest that novel formulation SS was potentially safe for chronic administration in rats, and no significant differences (p > 0.05) were observed in tested parameters on day 3 and day 8 when compared to the day 0 (baseline) values in healthy volunteers. Healthy volunteers did not report any adverse effects or any other complications during the treatment period and the follow-up period. Therefore, it can be concluded that the novel preparation Sudarshana suspension does not cause any significant toxic effects on the blood parameters in animal and human models.

Toxicological implications of the fruit of Harungana madagascariensis on wistar rats

BackgroundThe unopened buds of the fruit of Harungana madagascariensis is used in the treatment of anaemia and skin diseases in traditional medicine. Hence, this study aims to scientifically evaluate the effects of oral administration of the fruit extract of Harungana madagascariensis on haematological, biochemical and histological parameters in Wistar rats.MethodsPhytochemical screening of the ethanol fruit extract of H. madagascariensis was carried out. Acute toxicity test was done using Lorke’s method. Sub-acute toxicity studies were done using 24 rats of both sexes which were randomized into four groups of six rats each. Animals in groups A, B, C were administered with the extract at doses of 250, 500 and 1000 mg/kg, respectively while group D animals were given distilled water (5 mg/kg) and served as the control group. All administrations were done through the oral route for 30 consecutive days. Body weights of the animals were taken weekly during the study. The animals were sacrificed under diethyl ether anaesthesia and blood samples collected for evaluation of haematological (red blood cell, haemoglobin, packed cell volume and white blood cell) and biochemical (alanine transferase, alanine aminotransferase, alkaline phosphatase, urea, creatinine, total cholesterol and total protein) parameters. Histological examination was conducted on the liver and kidney of the animals.ResultsPreliminary phytochemical screening of the extract revealed the presence of alkaloids, anthraquinones, steroidal nucleus, saponins, carbohydrates, flavonoids, and tannins. Acute toxicity test showed that the LD50 was greater than 5000 mg/kg. There was no statistically significant (P < 0.05) difference in the RBC, HB, PCV and WBC of the extract treated groups when compared to the control group. There was however, a statistically significant (P < 0.05) difference in the creatinine level of the 500 mg/kg extract –treated group and the control. There was no statistically significant (P < 0.05) difference in other biochemical parameters of the extract treated groups and the control group except for a marginal increase in the total protein in the group treated with 1000 mg/kg of the extract (60 g/L) compared with control (54.80 g/L). Histopathological examination showed alterations in the morphology of the liver and kidney in extract treated groups as compared to the control groups.ConclusionThe findings have revealed that the ethanol fruit extract of H. madagascariensis should be used with caution especially during prolonged usage as the histology showed it has nephrotoxic and hepatotoxic potentials. Further studies will be done to establish the effects of the extract on white blood cells.

HPLC characterization, acute and sub-acute toxicity evaluation of bark extract of Rhizophora mucronata in Swiss Albino mice

AimRhizophora mucronata, commonly called as ‘red mangrove’ grows in the tropical and sub-tropical regions and on the sheltered shores. The bioactive compounds from the plant have been used in the treatment of wide range of diseases. Though the beneficial effects have been reported, the safety and toxicological studies are not carried out. Hence, major bioactives have been identified by HPLC and then acute and sub-acute toxicity studies of (BERM) in Swiss Albino mice have been carried out. Main methodsHPLC fingerprinting was carried out of BERM for the characterization of bioactives. BERM as a single dose was given orally at 800, 1600 mg/kg and 3200 mg/kg by a stainless steel cannula to the mice. Then the mice were observed for 14 days for mortality and behavioural changes. Food, water intake and body weight changes were also observed throughout the study period. On the fifteenth day, the mice were anesthetized with isofluorane and blood was withdrawn for haematological and biochemical analysis. The animals were sacrificed by overdose of isofluorane and organs such as liver, kidney, lungs and spleen were dissected out for histopathological analysis. There was no mortality of the mice even in 3200 mg/kg dose, stating that the oral LD50 of BERM is more than 5000 mg/kg. In terms of Sub-acute toxicity, for a period of 28 days repeated dose of 400 mg/kg and 800 mg/kg as an optimum dose and a control group was kept with only distilled water at 5 ml/kg against the treated groups. On 29th day, the mice from all groups were sacrificed and blood was withdrawn and organs such as liver, kidney, lungs and spleen were dissected out for the assessment of internal tissues, wherein no abnormalities were observed in the treatment groups as compared to the control. The blood parameters, biochemical analysis of the treated groups were well within the range, histopathological confirmed the findings wherein the organs viz, liver, kidneys, lungs and spleen possessed normal architecture. Key findingsBased on HPLC results, prominent 5 major compounds viz: Diadzein, Epicatechin, Hesperidin, Diosmin and Quercitrin respectively were identified. Isolated changes observed in the haematological, biochemical and histopathological studies were not dose related and showed the safety of the bark extract. Similarly, the sub-acute toxicity of BERM has been conducted for 28 days, wherein repeated dose of 400 mg/kg and 800 mg/kg and control group was given orally. There were no abnormalities found both in external and internal parameters. SignificanceBased on the study it is concluded that the bark extract of Rhizophora mucronata (BERM) is safe at 1000 mg/kg or less on repeated dosage can be considered as a safe dose for pharmacological efficacy studies.

Subacute toxicity study of an aqueous extract of dried leaves of Gymnosporia spinosa on albino rats

Background: Leaves of Gymnosporia spinosa have been used by people for treatment of jaundice. Traditional herbal drugs are popular all over the world and it is presumed that herbal medicines have lesser or no side effects. This generalized belief and no information available regarding toxicity study of G. spinosa with search from limited available information prompted us to carry out work on subacute toxicity study of aqueous extract of dried leaves of G. spinosa.Methods: Subacute toxicity study was carried out using aqueous extract of G. spinosa leaves. 30 rats of either sex were randomly divided in to 4 groups. First group received distilled water (control). Second, third and fourth groups received single daily dose of drug orally as 40, 120 and 240 mg/100 g of body weight respectively for 3 weeks. Animals were observed for various parameters. After 21 days blood was collected for blood counts and biochemical parameters. Liver, lungs and kidney were subjected to histo-pathological studies.Results: Throughout study there was no mortality in any group. Degenerative changes in the liver. Other organ does not show any changes. Analysis of biochemical data showed serum glutamic pyruvic transaminase and s. alkaline phosphatase levels were decreased. Serum bilirubine, blood urea and serum creatinine level were increased significantly.Conclusions: The data showed that there was hepato-renal toxicity at higher dose level which is about 100x human therapeutic dose.

Evaluation of Sub-acute and Sub Chronic Toxicity Profile of the Aqueous Leaf Crude Extract of Melanthera Scandens (Schumach &amp; Thonn) in Wistar Rats

Aims: Although Melanthera scandens is a plant widely used in traditional medicine for the management of seizures, stomach ulcers and sores, dysmenorrhea, diabetes and malaria, there was scanty information about its safety. There was, therefore, a need to evaluate the sub-acute and subchronic toxicity studies of this plant which would reflect on its safety.&#x0D; Methodology: This was an experimental laboratory study. The research was conducted at Kampala International University-Western Campus at the Pharmacology laboratory from February to June 2017. The sub-acute toxicity was evaluated after administering daily oral doses of M. scandens crude extract (250, 500 and 1000 mg/kg) for 28 days and 90 days for subchronic study, after which the effect on haematological, biochemical and histopathological parameters were assessed in male and female Wistar rats (five of each sex).&#x0D; Results: Sub-acute toxicity results revealed that there was a significant decrease in the AST between the male Wistar rats that received 250 mg/kg (P= .005) and those that received 500 mg/kg (P= .05) as compared with the control group. Subchronic studies showed a significant increase in ALP (P= .05) at 1000 mg/kg compared with 500 mg/kg. Terminal necropsy did not reveal any treatment-related histopathological findings. There were also no toxicologically significant treatment-related effects on haematological parameters. The sub-acute toxicity results suggest that doses of 250mg/kg and 500mg/kg are safe and could be hepatoprotective due to reduced levels of AST and ALP, while the subchronic toxicity study results suggest that doses greater than 1000 mg/kg could be toxic to the plasma membrane, liver cells or endoplasmic reticulum due to increased ALP levels at this dose.&#x0D; Conclusion: The M. scandens crude extract did not cause significant toxicity on haematological and histopathological indices, after sub-acute and subchronic administration in Wistar rats.

Evaluation of Acute and Sub-acute Toxicity of the Aqueous Extract from the Fruit of Solanum indicum Linn. (Solanaceae) in Rats

Aim: The fruit of Solanum indicum Linn have been reported traditionally to have anti-hypertensive and diuretic properties. This study was undertaken to evaluate the toxicological potential of S. indicum fruits aqueous extract through the acute and sub-acute toxicity tests in rats.&#x0D; Methodology: For acute toxicity evaluation, a single oral dose of 5000 mg/kg of the plant extract was administrated in 60 days old female albino Wistar rats. Then, the animals were observed for 14 days. Sub-acute toxicity studies were conducted with 50 adult rats of both gender that orally received during 28 days, increasing doses of the plant extract. Their body weight and food intake were weekly collected. At the end of the experiment, biochemical and hematological parameters as well as histological analysis of organs (liver, kidneys and spleen) were undertaken.&#x0D; Results: Single oral administration of 5000 mg/kg dose of the fruit plant aqueous extract produced no mortality or signs of toxicity. During sub-acute test, no variations in body weight and food intake of both animals gender were observed. An important decrease in male’s rat liver weight were obtained at the dose 25 mg/kg; serum urea, total cholesterol, TAG, ALP and AST levels were significantly lowered in male especially at the dose 50 mg/kg, but this decrease was noticed only in serum urea, ALP and ALT in female rats. Furthermore, a significant decrease in platelets number, serum PCT, MPV and PDW levels were recorded in all treated male rats except those receiving the highest extract dose. No structural changes in treated animal organs section histology were observed when compared to controls.&#x0D; Conclusion: The fruits aqueous extracts of S. indicum is safe when administered acutely and for 28 days in rats. However, alterations on their hematological and biochemical parameters were not closely related with the dose, implying caution on its use.

Assessment of Acute and 28-Days Repeated Dose Sub-Acute Toxicity Study of Selected Ultra-Diluted Preparations in Wistar Rats

Objective: The aim of this work was to investigate the acute and sub-acute toxicity studies of the homeopathic drugs, causticum, calcerea, medorrhinum, mercurius, formica, proteus, silica, sulphur, thuja in experimental models. Materials and Methods: Animals were divided into groups (n=5). Homeopathic drugs were administered to rats for 14 and 28 days to assess the toxicological profile. Acute and sub-acute studies were carried out according to OECD 425, 407 guidelines. Behavioural parameters and mortality rate were assessed in acute toxicity study. The sub-acute was performed for a study period of 28 days and afterwards animals were sacrificed to carry out biochemical and haematological estimations. The histopathological analysis of all vital organs was done with haematoxylin and eosin staining to assess the anatomical damage involved. Results: Findings of the study revealed that the administration of homeopathic drugs at single bolus dose in acute toxicity study there were no mortality or any signs of toxicity observed after oral administration of drugs up to the dose level that of 2000 μl in rats. So, the LD50 was found to be greater than 2000 ul/100g body weight. Sub-acute toxicity study was conducted for a period of 28 days and we noted that the there were no pathological or biochemical alterations found. Conclusion: Study inferred that homeopathic drugs are safe on acute and sub-acute administration for 14 and 28 days respectively. The safety profile is established in experimental animals and further data can be corroborated in humans.

Evaluation of Acute and Subacute Toxicities of Psidium guajava Methanolic Bark Extract: A Botanical with In Vitro Antiproliferative Potential.

The methanol crude extract of the bark of Psidium guajava (guava) previously displayed interesting cytotoxic effects on a panel of human cancer cell lines. In the present work, we plan to determine the toxicological effects of this guava botanical in Wistar rats. Acute oral toxicity of the extract was carried out by administration of a single dose of 5000 mg/kg body weight to female rats in 14 days. Subacute toxicity was conducted by oral administration of the extract at daily doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg body weight, respectively, while rats in the control group received no extract. After 28 days of treatment, animals were sacrificed for hematological and biochemical studies. In the acute toxicity study, no mortality or signs of toxicity were recorded; hence, the median lethal dose (LD50) of the Psidium guajava bark extract is greater than 5000 mg/kg body weight. For the subacute toxicity study, significant variations in body weight, relative weight of organs, and biochemical parameters were observed in the animals treated at different doses of the plant extract compared to control animals. Histopathological analyses showed minor liver inflammation in females treated at the highest dose (1000 mg/kg). These results suggest that intake of a single high dose of the Psidium guajava bark extract is nontoxic, but repeat administration could exhibit mild organ toxicity.

Toxological evaluation of Cyperus compressus Linn., a traditionally used anthelmintic plant in India

This study reports the toxicological evaluation findings of Cyperus compressus Linn., (Cyperaceae), whose root decoction is used in India to treat the intestinal helminthic infestations. The acute oral toxicity (AOT) of C. compressus root extract (CRE) was conducted in Swiss mice, following OECD guidelines 407. The sub-acute toxicity study of CRE was undertaken in Wistar rats, using three doses viz., 175, 350 and 700 mg/kg, involving haematological, biochemical and transmission electron microscopy (TEM) parameters. AOT study revealed the median lethal dose of CRE to be above 2000 mg/kg. The sub-acute study of CRE revealed elevated levels of serum glutamic oxaloacetic transaminase in male rats, only in high extract-treated group, but the serum glutamic pyruvic transaminase was found to be elevated both in male and female animals. TEM studies of kidney and liver of animals also revealed considerable deformities in the nucleus and mitochondria in the form of damages to nuclear membrane, cristae and to double layered membrane of mitochondria, only in the high-extract treated group of animals. The root decoction of C. compressus show presence of toxicity in the highest dose tested animals. Therefore, the use of this plant extract against intestinal helminthiasis raises concerns about its safety.

Acute and Subacute Toxicity Studies of the Ethyl Acetate Soluble Proanthocyanidins of the Immature Inflorescence of Cocos nucifera L. in Female Wistar Rats.

Ayurvedic and traditional medical practitioners of Sri Lanka use the decoction of the immature inflorescence of Cocos nucifera L. (IC) variety aurantiaca for the treatment of menorrhagia. The progestogenic effect of the ethyl acetate soluble proanthocyanidins (EASPA) of the IC in female rats at a dose of 3.5 mg/kg body weight has been reported. Acute and subacute toxicity studies of EASPA of the IC carried out using female Wistar rats according to Organization for Economic Co-operation and Development (OECD) guidelines 423 and 407, respectively, are reported herein. In the acute toxicity study, a single dose of EASPA (2000 mg/kg body weight) was orally administered to rats, which were monitored for 14 days. In the subacute toxicity study, rats were orally administered with EASPA daily for 28 days at doses of 1.75, 3.5, 7, and 14 mg/kg body weight. No rat in either the acute or subacute toxicity study exhibited mortality or clinical signs of toxicity. Further, these rats did not show any significant change in their mean body weight, food, and water intake, haematological and biochemical parameters as well as in the results of their histopathological examinations compared to those of control group rats. According to results of the acute toxicity, the LD50 of EASPA is estimated to be greater than 2000 mg/kg body weight. Considering the results of the subacute toxicity study, the oral administration of EASPA daily for 28 days was well tolerated up to the dose, 14 mg/kg by rats. These results will be useful in the development of a novel therapeutic agent from EASPA of the IC for the treatment of menorrhagia, which incapacitates a considerable proportion of women worldwide.

Safety Assessment of Methanol Extract of Melastoma malabathricum L. Leaves following the Subacute and Subchronic Oral Consumptions in Rats and Its Cytotoxic Effect against the HT29 Cancer Cell Line.

Methanol extract of Melastoma malabathricum (MEMM) has been traditionally used by the Malay to treat various ailments. In an attempt to develop the plant as an herbal product, MEMM was subjected to the subacute and subchronic toxicity and cytotoxicity studies. On the one hand, the subacute study was performed on three groups of male and three groups of female rats (n = 6), which were orally administered with 8% Tween 80 (vehicle control group) or MEMM (500 and 1000 mg/kg) daily for 28 days, respectively. On the other hand, the subchronic study was performed on four groups of rats (n = 6), which were orally administered with 8% Tween 80 (vehicle control group) or MEMM (50, 250, and 500 mg/kg) daily for 90 days, respectively. In the in vitro study, the cytotoxic effect of MEMM against the HT29 colon cancer cell line was assessed using the MTT assay. MEMM was also subjected to the UHPLC-ESI-HRMS analysis. The results demonstrated that MEMM administration did not cause any mortality, irregularity of behaviour, modification in body weight, as well as food and water intake following the subacute and subchronic oral treatment. There were no significant differences observed in haematological parameters between treatment and control groups in both studies, respectively. The in vitro study demonstrated that MEMM exerts a cytotoxic effect against the HT29 colon cancer cell line when observed under the inverted and phase-contrast microscope and confirmed by the acridine orange/propidium iodide (AOPI) staining. The UHPLC-ESI-HRMS analysis of MEMM demonstrated the occurrence of several compounds including quercetin, p-coumaric acid, procyanidin A, and epigallocatechin. In conclusion, M. malabathricum leaves are safe for oral consumption either at the subacute or subchronic levels and possess cytotoxic action against the HT29 colon cancer cells possibly due to the synergistic action of several flavonoid-based compounds.

English

The side effects prediction is a regulatory requirement prior the effective use of a new product as drug or pesticide constituent is allowed. The handling hazards of Cymbopogon schoenanthus essential oils (CSEO) were determined by investigating their acute and subacute toxicities as well as irritancy potential for eye and skin in compliance with the Organization for Economic Cooperation and Development guidelines. In mice, the essential oils did not induce mortality at the limit single dose of 2000 mg/kg b.w., meaning that the test product estimated LD50 is 5000 mg/kg b.w. In the 28 days sub-acute oral toxicity study in rats, there was no mortality observed for all tested doses in both sex. Furthermore, besides body weight gain that slightly dropped, there was no significant difference observed in food and water consumption, relative organs weight, and blood biochemical profile in test animals, compared to the control. No eye irritant reaction was shown in the rabbits exposed to CSEO. To assess dermal irritation, rabbits were dermally exposed to CSEO for 4 h. The results showed that no adverse reactions such as erythema and edema were observed throughout the test. Based on these findings, CSEO do not cause either oral toxicity up to 28 days in repeated administration, nor dermal and eye irritation, and seems to be safe for animal in the study conditions. These results constitute a new scientific support for the safe use of C. scheonanthus essential oils as alternatives to synthetic pesticides. However, for further clinical relevance of the results and complete toxicological profile elucidation, toxicity studies must be extended to long term toxicity test as subchronic and chronic toxicities, reprotoxicity, carcinogenicity, teratogenicity, and mutagenicity investigations. Key words: Cymbopogon schoenanthus, Wistar rat, essential oils, sub-acute toxicity, blood chemistry, naturel insecticide. &nbsp;

Comprehensive Biosafety Assessment of Additives based on Live Microorganisms

When developing veterinary or feed preparations, a mandatory procedure is the study of their toxicological properties in living bio-objects. The purpose of this research work was to study the toxicological effect of probiotic on the basis of autochthonous microflora of birds by identifying the parameters of acute, subacute and chronic toxicity, as well as irritating characteristics in experimental laboratory animals. In studies of subacute and chronic toxicity, the pharmacodynamics of a probiotic was studied by its effect on individual metabolic parameters, morphobiochemical composition of blood, and also the growth rate of experimental laboratory animals. A complex of toxicological studies of the developed biological product showed that the probiotic does not exhibit toxic and irritating properties, stimulates hematopoiesis, erythropoiesis, there is a slight increase in the mass of laboratory animals in connection with which it can be used for its intended purpose, regardless of the dose.