Reverse Mutation Test Research Articles

Genotoxicity evaluation of Guibi-Tang extract using an in vitro bacterial reverse mutation assay, chromosome aberration assay, and in vivo micronucleus test.

BackgroundGuibi-Tang is a traditional herbal prescription made from 12 different herbs that is used in the treatment of amnesia and poor memory.MethodsIn the present study, we evaluated the acute oral toxicity and genotoxic potential of Guibi-Tang water extract (GBT) at doses up to 2000 μg/plate an using a bacterial reverse mutation test (Ames test) with Salmonella typhimurium strains TA100, TA1535, TA98, and TA1537, and Escherichia coli strain WP2uvrA. Acute toxicity and genotoxic potential were measured in the presence and absence of an exogenous source of metabolic activation, in an in vitro chromosome aberration assay with Chinese hamster lung (CHL) cells, and in an in vivo micronucleus test using ICR mice bone marrow as recommended by the Korean Food and Drug Administration. An acute oral toxicity test of GBT was performed in Sprague Dawley rats. The Ames test showed that GBT did not induce gene mutations in S. typhimurium or in E. coli in the presence or absence of S9 activation.ResultsGBT did not significantly increase the number of structural aberrations in CHL cells with or without S9 activation. The oral administration of GBT at a dose of up to 2000 mg/kg caused no significant increase in the number of micronucleated polychromatic erythrocytes or in the mean ratio of polychromatic to total erythrocytes.ConclusionsHowever, as we did not identify the components of GBT responsible for these effects, other assays are needed to confirm its genotoxicity.

Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm).

The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions.

Evaluation of Genotoxicity of CSE1034 by Ames and <i>In vitro</i> Chromosomal Aberration Tests

Purpose: To evaluate the genotoxicity of CSE1034, a novel antibiotic adjuvant entity, using bacterial reverse mutation assay (Ames test) and in vitro chromosomal aberration test.Methods: Reverse mutation test was carried out using four strains of Salmonella typhimurium (TA 98, TA100, TA1535 and TA1537) and one strain of E. coli [WP2 (uvrA)], while chromosomal aberration test was done with cultured Chinese hamster lung (CHL) cells. Reverse mutation test was carried out in a dose range of 0.0015 to 0.16 ìg/plate in triplicate with and without S9 activation.Results: No significant increases in the number of revertants were observed at the dose levels where antibacterial effects were not noted. CSE1034 caused no increase in the number of chromosomal aberrants at dose levels of 0.34, 0.69, 1.37, 2.75 and 5.50 mg/ml in the absence and presence ofmetabolic activation.Conclusion: Based on the above observations, it can be concluded that CSE1034 has no mutagenic activity.Keywords: CSE1034, reverse mutation, antibiotic adjuvant entity, Chromosomal aberration, Mutagenic

Safety evaluation of a whey protein fraction containing a concentrated amount of naturally occurring TGF-β2

TM0601p is a whey protein isolate derived from cow milk, containing a concentrated amount of transforming growth factor β2 (TGF-β2), and is intended for nutritional use in infants and adults. In vivo and in vitro studies have been performed to evaluate the safety of this product. In a 13-week toxicity study, treatment of adult Sprague–Dawley rats by gavage at up to 2000mg/kg/day did not result in any significant findings other than minor non-adverse changes in urinary parameters in females. The no-observed-adverse-effect level (NOAEL) was established as 2000mg/kg/day. In a juvenile toxicity study, rat pups received 600mg/kg/day by gavage from postnatal day (PND) 7 to PND 49. Transient lower bodyweight gain in the pre-weaning period was attributed to gastrointestinal effects of the viscous test material; following weaning, bodyweight gain was comparable to the vehicle controls. Reduced eosinophil counts and changes in urinary parameters (females) were recorded in treated pups at PND 49, and higher thymus weights were recorded in males only at the end of the recovery period (Day 77). None of the findings were considered adverse. There were no other significant findings and the NOAEL was established as 600mg/kg/day. No evidence of genotoxicity was seen in the bacterial reverse mutation test or the in vitro micronucleus test. Overall the results obtained present a reassuring safety profile for TM0601p.

Toxicological evaluation of 6:2 fluorotelomer alcohol

6:2 fluorotelomer alcohol (6:2 FTOH; CF3[CF2]5[CH2]2OH, CAS# 647-42-7) was evaluated for acute, genetic, and subchronic toxicity using in vitro and in vivo methods. In rats, 6:2 FTOH was considered to be slightly toxic by the oral (LD50=1750mg/kg), and dermal (LD50>5000mg/kg) routes. In rabbits, 6:2 FTOH was not a primary skin or eye irritant, and it did not produce a dermal sensitization response in mice. In a 90-day subchronic study, 6:2 FTOH was administered to rats by oral gavage (0, 5, 25, 125, 250mg/kg/day). Mortality was observed at 125 and 250mg/kg/day; deaths occurred after approximately three weeks of dosing and continued sporadically. The NOAEL in the subchronic study was 5mg/kg/day based on hematology and liver effects. 6:2 FTOH was not mutagenic in the bacterial reverse mutation test or in the mouse lymphoma assay and was not clastogenic in a chromosome aberration assay in human lymphocytes. The hazard classification for human health endpoints of 6:2 FTOH according to the United Nations Globally Harmonized System of Classification and Labeling of Chemicals (GHS) is Category 4 for acute oral toxicity based on an LD50 of 1750mg/kg. Other acute health endpoints including eye and skin irritation, skin sensitization, as well as genotoxicity, did not meet the criteria for hazard classification. Benchmark Dose Analysis was performed on the most sensitive endpoints from the 90-day oral gavage study and these levels were all above the study NOAEL of 5mg/kg/day. For risk assessment purposes, the recommended point of departure is the more conservative study NOAEL of 5mg/kg/day.

Genotoxicity profile of erinacine A-enriched Hericium erinaceus mycelium

Hericium erinaceus (H. erinaceus) has a long history of usage in traditional Chinese medicine for the treatment of gastric disorders. Recently, it has become a well-established candidate in causing positive brain and nerve health-related activities by inducing nerve growth factor (NGF) from its bioactive ingredient, erinacine A. This active compound, which exists only in fermented mycelium but not in its fruiting body, increases NGF levels in astroglial cells in vitro as well as catecholamine and NGF levels in vivo. With increasing recognition of erinacine A in H. erinaceus (EAHE) mycelium improving neurodegenerative diseases, numerous products are being marketed based on these functional claims. To our knowledge, there have been no reports on the mutagenicity of EAHE prior to this paper. Hence, the present study was undertaken to determine the mutagenicity and genotoxicity effects of EAHE mycelium conducted in three standard battery of tests (reverse mutation, chromosomal aberration, and micronuclei tests) according to the latest guidelines in order to meet all international regulatory requirements and provide information on the safety of this new and promising natural remedy. Our results have indicated that EAHE mycelium did not significantly increase the number of revertant colonies in the bacterial reverse mutation test nor induce higher frequency of aberrations in the chromosome aberration test. Moreover, no statistically significant EAHE mycelium-related increase was observed in the incidence of reticulocytes per 1000 red blood cells and micronucleated reticulocytes per 1000 reticulocytes. In conclusion, the three standard battery of tests suggested that EAHE mycelium was devoid of mutagenicity and genotoxicity in the tested doses and experimental conditions.

Genotoxicity and subacute toxicity studies of a new astaxanthin-containing <i>Phaffia rhodozyma</i> extract

Experimental and clinical studies demonstrate that astaxanthin (AXN), a xanthophyll carotenoid, has protective effects against oxidative damage. Because most of these studies assessed AXN derived fromHaematococcus pluvialisthat were cultivated at industrial scales, few studies have examined the toxicity of AXN derived fromPhaffia rhodozyma. To evaluate the safety of astaxanthin-containingP. rhodozymaextract (AXN-PRE), genotoxicity was assessed in bacterial reverse mutation test and mouse bone marrow micronucleus test, and general toxicity was assessed in 4-week repeated oral toxicity study in rats. AXN-PRE did not induce reverse mutations in theSalmonella typhimuriumstrains TA98 or TA100 at concentrations of 5,000 µg/plate with or without S9 mix, and no chromosome damage was observed at a dose of 2,000 mg/kg in mouse micronucleus test. In the subacute toxicity study, male and female Sprague-Dawley rats were given AXN-PRE at doses of 0, 500, and 1,000 mg/kg by gavage for 4 weeks. Body weights, urinalysis, hematology, serum biochemistry, organ weights, or histopathological lesions indicated no distinct toxicity. In conclusion, AXN-PRE had no effect in bacterial reverse mutation test and mouse bone marrow micronucleus test. The no-observed-adverse-effect level for AXN-PRE in 4-week repeated oral toxicity study in rats was determined to be greater than 1,000 mg/kg (corresponding to dose of 50 mg/kg AXN) regardless of gender.

Ethoxyquin

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of ethoxyquin (CAS No. 91-53-2), an antioxidant and a plant growth regulator. The data from all the in vitro reverse mutation tests were negative, while positive results were obtained in chromosomal aberration tests using Chinese hamster ovary cells and human peripheral blood lymphocytes and also in the mouse lymphoma TK test. As for in vivo studies, ethoxyquin gave a weak positive response in the liver micronucleus test in juvenile rats, but negative responses in the mouse bone marrow micronucleus test and the unscheduled DNA synthesis test using rat liver. Although ethoxyquin and/or its metabolite(s) induce chromosomal aberration, the influence on the chromosomal aberration is likely to be associated with ethoxyquin’s action on the functional protein component rather than the direct DNA damage in the body. Results from the 30-month combined chronic toxicity/carcinogenicity study suggest that ethoxyquin has a carcinogenic potential in the urinary bladder in female rats. Therefore, it is unlikely that ethoxyquin in normal uses exerts the carcinogenicity through a genotoxic mechanism. Based on various data, FSCJ designated ethoxyquin and its dimer to the residue definition in agricultural products. Residual ethoxyquin dimer has been found as an ethoxyquin metabolite at a substantial level in cultured fishes such as salmons. Toxicity of the dimer has been studied only in one 90-day subacute toxicity test where the toxicity was not observed at the dose of 12.5 mg/kg body weight/day. Ethoxiquin used for the most of toxicity studies seems to contain ethoxiquin dimer as an impurity. Taking the results from such toxicity studies into consideration, it is unlikely that toxicity of the dimer is stronger than that of the parent compound. Among the no-observed-adverse-effect levels (NOAELs) obtained in various studies, the lowest NOAEL was 2 mg/kg body weight/day obtained in the 90-day subacute toxicity study in dogs. FSCJ, however, judged that it was more appropriate to adopt the lowest-observed-adverse-effect level (LOAEL) of 2.5 mg/kg body weight/day obtained in the two-generation reproduction toxicity study in dogs which was performed more recently and administered for a longer period of time, as a basis for acceptable daily intake (ADI). Accordingly, FSCJ specified the ADI for ethoxyquin as 0.0083 mg/kg body weight/day, based on this LOAEL and applying a safety factor of 300.

고삼추출물의 in vitro 항돌연변이원성과 유전독성 연구

Sophorae radix extract (SRE) has been registered as an environment-friendly organic material that is widely used in the cultivation of crops in Korea. Matrine, the active ingredient in SRE, was reported as a toxic substance in the nervous system in mice. However, no information is available on its toxic effects in other organisms. Therefore, antimutagenicity and two kinds of genotoxicity tests (bacterial reverse mutation and chromosome aberration test) of two samples of SRE were investigated in this study. Antimutagenicity test was experimented by using bacterial reverse mutation test. In the reverse mutation test, Salmonella Typhimurim TA98, TA1535 and TA1537 were used to evaluate the mutagenic potential of SRE. Bacterial reverse mutation test was also performed on positive and negative control groups in the presence of the metabolic activation system (with S-9 mix) and metabolic non-activation system (without S-9 mix). In the chromosome aberration test, Chinese hamster lung cells were exposed to SRE for 6 or 24 hours without S-9 mix, or for 6 hours with S-9 mix. Negative and positive control groups were experimented for chromosome aberration test. As a result, the number of mutated colonies induced by 4-NQO were reduced by SRE treatment in all strains, indicating that SRE may have antimutagenic effects. Reverse mutation was not shown at all concentrations of SRE, regardless of application of the metabolic activation system. In the chromosomal aberration test, one of the SRE sample gave a suspicious positive result at 250 µg/ml in the presence of S-9 mix. For the more adequate evaluation of the genotoxic potential of SRE samples, other in vivo genotoxicity study is needed.

Genotoxicity Assessment of Erythritol by Using Short-term Assay

Erythritol is a sugar alcohol that is widely used as a natural sugar substitute. Thus, the safety of its usage is very important. In the present study, short-term genotoxicity assays were conducted to evaluate the potential genotoxic effects of erythritol. According to the OECD test guidelines, the maximum test dose was 5,000 μg/plate in bacterial reverse mutation tests, 5,000 μg/ml in cell-based assays, and 5,000 mg/kg for in vivo testing. An Ames test did not reveal any positive results. No clastogenicity was observed in a chromosomal aberration test with CHL cells or an in vitro micronucleus test with L5178Y tk+/− cells. Erythritol induced a marginal increase of DNA damage at two high doses by 24 hr of exposure in a comet assay using L5178Y tk+/− cells. Additionally, in vivo micronucleus tests clearly demonstrated that oral administration of erythritol did not induce micronuclei formation of the bone marrow cells of male ICR mice. Taken together, our results indicate that erythritol is not mutagenic to bacterial cells and does not cause chromosomal damage in mammalian cells either in vitro or in vivo.

Optimal descriptor as a translator of eclectic data into endpoint prediction: Mutagenicity of fullerene as a mathematical function of conditions

The experimental data on the bacterial reverse mutation test on C60 nanoparticles (TA100) is examined as an endpoint. By means of the optimal descriptors calculated with the Monte Carlo method a mathematical model of the endpoint has been built up. The model is the mathematical function of (i) dose (g/plate); (ii) metabolic activation (i.e. with S9 mix or without S9 mix); and (iii) illumination (i.e. dark or irradiation). The statistical quality of the model is the following: n=10, r2=0.7549, q2=0.5709, s=7.67, F=25 (Training set); n=5, r2=0.8987, s=18.4 (Calibration set); and n=5, r2=0.6968, s=10.9 (Validation set).

Evaluation of in vitro mutagenic and antimutagenic activity of vitae elixxir by Ames salmonella microsome assay..

The Ames Salmonella / microsome mutagenicity assay (Ames test) is a short-term bacterial reverse mutation test specifically designed to detect a wide range of chemical substances that can produce genetic damage leading to gene mutations. Vitae Elixxir is a mixture of nine herbal extracts with Chlorophyllin and Allicin. All herbs from Vitae Elixxir are medicinally very important with variety of roles in the different disorders or diseases, when studied individually by researchers. In spite of clinical use of Vitae Elixxir, no information is available on its toxicity, mutagenicity, antimutagenicity or anticarcinogenic potential. In present study, mutagenic and antimutagenic potential of Vitae Elixxir, was evaluated using plate incorporation assay, preincubation assay and modulation assay. The positive controls such as 4-NQNO, 2-AF, Danthron and MMS were used with and without S9. Ames Salmonella histidine reversion assay was studied using standard strains of Salmonella typhimurium TA97a, TA98, TA100 and TA102 with and without S9. In plate incorporation assay, Vitae Elixxir was not mutagenic at and up to 500 mg/plate. It exhibits the anti-mutagenic potential at 500 to 1000mg/plate in preincubation test. Vitae Elixxir is an extremely potent inhibitor of the mutagenicity at 1000mg and 500mg/plate and significantly dose dependent anti-mutagenic activity in TA98 and TA100 with and without metabolic activation. Vitae Elixxir would be beneficial for prevention of malignancy.

한국산 겨우살이 추출물의 안전성 평가

Abstract Mistlero C was shown to be non-genotoxic in a series of genotoxicity tests, including a bacterial reverse mutation test and a combined in vivo mammalian erythrocyte micronucleus test. In a bacterial reverse mutation assay, no significant increases in the number of revertant colonies, compared to the negative control, was detected in 5,000 ㎍/plate of Mistlero C. In addition, with Mistlero C, no changes were shown in the number of micronucleated polychromatic erythrocytes (MNPCE) among 2,000 polychromatic erythrocytes compared to the negative control. Mistlero C was administered orally in rats to investigate acute toxicity. The LD 50 values in rats were above 2,000 ㎎/㎏. In a repeated dose, 13-week, oral toxicity study conducted in rats, no compound-related adverse effects were shown at doses of Mistlero C of up to 1,000 ㎎/㎏ body weight/day. The results of these studies support the safe use of Mistlero C in food for human consumption.Key words: mistletoe, genetic toxicity, micronucleus test, bacterial reverse mutation assay, toxicity

Mutagenic Assessment of Olmesartan Cilexetil by Bacterial Mutation Assay

Hypertension is a serious health problem due to high frequency and concomitant other diseases including cardiovascular and renal dysfunction. Olmesartan cilexetil is a new antihypertensive drug associated with angiotensin II receptor antagonist. This study was conducted to evaluate the mutagenicity of olmesartan cilexetil by bacterial reverse mutation test using Salmonella typhimurium (TA100, TA1535, TA98, and TA1537) and Escherichia coli (WP2 uvrA). At the concentrations of 0, 62, 185, 556, 1667, and 5000 μg/ plate, olmesartan cilexetil was negative in both Salmonella typhimurium and Escherichia coli regardless of presence or absence of metabolic activation system (S9 mix). These results demonstrate that olmesartan cilexetil does not induce bacterial reverse mutation.

Safety Evaluation of Chrysanthemum indicum L. Flower Oil by Assessing Acute Oral Toxicity, Micronucleus Abnormalities, and Mutagenicity

Chrysanthemum indicum is widely used to treat immune-related and infectious disorders in East Asia. C. indicum flower oil contains 1,8-cineole, germacrene D, camphor, α-cadinol, camphene, pinocarvone, β-caryophyllene, 3-cyclohexen-1-ol, and γ-curcumene. We evaluated the safety of C. indicum flower oil by conducting acute oral toxicity, bone marrow micronucleus, and bacterial reverse mutation tests. Mortality, clinical signs and gross findings of mice were measured for 15 days after the oral single gavage administration of C. indicum flower oil. There were no mortality and clinical signs of toxicity at 2,000 mg/kg body weight/day of C. indicum flower oil throughout the 15 day period. Micronucleated erythrocyte cell counts for all treated groups were not significantly different between test and control groups. Levels of 15.63~500 μg C. indicum flower oil/plate did not induce mutagenicity in S. Typhimurium and E. coli, with or without the introduction of a metabolic activation system. These results indicate that ingesting C. indicum flower oil produces no acute oral toxicity, bone marrow micronucleus, and bacterial reverse mutation.

Evaluation of Genotoxicity of CVA1020 through Ames and <em>in Vitro</em> Chromosomal Aberration Tests

The aim of the present study was to assess the mutagenic potential of CVA1020 using the bacterial reverse mutation assay (Ames test) with bacteria and <em>in Vitro</em> chromosomal aberration test with mammalian cells. In the reverse mutation test, <em>Salmonella typhimurium</em> TA 98, TA100, TA1535 and TA1537 and <em>Escherichia coli</em> [WP2 (uvrA)] were used with the dose range from 0.0015 to 0.16 μg/plate in triplicates with and without S9 activation. In the chromosomal aberration test with mammalian cells, a Chinese hamster lung fibroblast cell line (CHL/IU) in culture was used at dose levels 0.34, 0.69, 1.37, 2.75 and 5.50 mg/mL in the absence and presence of the metabolic activation. CVA1020 induced no significant increases in the number of revertants in any of the strains at the dose levels where antibacterial effects were not noted with and without metabolic activation. CVA1020 did not induce increase in the incidence of cells with chromosomal aberration or those with genome mutation (polyploidy) in any of the strains irrespective of the absence or presence of metabolic activation. Thus, based on these results it is concluded that CVA1020 does not have mutagenic potential.

Safety and toxicological evaluation of a novel, water-soluble undenatured type II collagen

This study was conducted to determine the broad-spectrum safety of a novel, water-soluble undenatured type II collagen (NEXT-II) derived from chicken sternum cartilage. The presence of epitope in NEXT-II was confirmed by using a commercial kit. The acute oral LD50 of NEXT-II was found to be greater than 5000 mg/kg bw in rats, while the single-dose acute dermal LD50 was greater than 2000 mg/kg bw. The primary dermal irritation index (PDII) of NEXT-II was found to be 1.8 and classified as slightly irritating to the skin. In primary eye irritation studies, the maximum mean total score (MMTS) of NEXT-II was observed to be 7.3 and classified as minimally irritating to the eye. Long-term safety studies were conducted in dogs over a period of 150 d, and no significant changes were observed in body weight, heart rate, respiration rate and blood chemistry. NEXT-II does not induce mutagenicity in the bacterial reverse mutation test in five Salmonella typhimurium strains either with or without metabolic activation. Furthermore, two experiments were conducted to assess the potential of NEXT-II to induce mutations with and without metabolic activation at the mouse lymphoma thymidine kinase locus using the cell line L5178Y. No biologically relevant increase of mutants was observed. Also, no dose-dependent toxicity was observed. Furthermore, colony sizing showed no clastogenic effects induced by NEXT-II under the experimental conditions. These studies demonstrated the broad spectrum of safety of NEXT-II.

In Vitro and In Vivo Studies of the Antiparasitic Activity of Sterol 14α-Demethylase (CYP51) Inhibitor VNI against Drug-Resistant Strains of Trypanosoma cruzi

Chagas disease affects more than 10 million people worldwide, and yet, as it has historically been known as a disease of the poor, it remains highly neglected. Two currently available drugs exhibit severe toxicity and low effectiveness, especially in the chronic phase, while new drug discovery has been halted for years as a result of a lack of interest from pharmaceutical companies. Although attempts to repurpose the antifungal drugs posaconazole and ravuconazole (inhibitors of fungal sterol 14α-demethylase [CYP51]) are finally in progress, development of cheaper and more efficient, preferably Trypanosoma cruzi-specific, chemotherapies would be highly advantageous. We have recently reported that the experimental T. cruzi CYP51 inhibitor VNI cures with 100% survival and 100% parasitological clearance both acute and chronic murine infections with the Tulahuen strain of T. cruzi. In this work, we further explored the potential of VNI by assaying nitro-derivative-resistant T. cruzi strains, Y and Colombiana, in highly stringent protocols of acute infection. The data show high antiparasitic efficacy of VNI and its derivative (VNI/VNF) against both forms of T. cruzi that are relevant for mammalian host infection (bloodstream and amastigotes), with the in vivo potency, at 25 mg/kg twice a day (b.i.d.), similar to that of benznidazole (100 mg/kg/day). Transmission electron microscopy and reverse mutation tests were performed to explore cellular ultrastructural and mutagenic aspects of VNI, respectively. No mutagenic potential could be seen by the Ames test at up to 3.5 μM, and the main ultrastructural damage induced by VNI in T. cruzi was related to Golgi apparatus and endoplasmic reticulum organization, with membrane blebs presenting an autophagic phenotype. Thus, these preliminary studies confirm VNI as a very promising trypanocidal drug candidate for Chagas disease therapy.

Acute oral toxicity and genotoxicity of Dryopteris crassirhizoma

Ethnopharmacological relevanceDryopteris crassirhizoma has been traditionally used for the treatment of tapeworm infestation, the common cold and cancer in Korea, China and Japan. Despite various pharmacological properties of Dryopteris crassirhizoma, there is no available information about the safety of Dryopteris crassirhizoma. Aim of this studyTo ensure more information about the safety of Dryopteris crassirhizoma, we performed the acute oral toxicity and genotoxicity tests of Dryopteris crassirhizoma. Materials and methodsThe acute oral toxicity test of Dryopteris crassirhizoma was performed in rats. Genotoxicity of Dryopteris crassirhizoma was evaluated by bacterial reverse mutation, chromosomal aberration and bone marrow micronucleus tests. ResultsIn acute toxicity test, Dryopteris crassirhizoma exhibited no mortality, body weight and behavioral changes and adverse effects in male and female rats. Dryopteris crassirhizoma did not significantly increase the number of the bacterial revertant and chromosomal aberration in both in vitro assays. Moreover, the Dryopteris crassirhizoma-related increases of micronucleated polychromatic erythrocytes (MNPCE) in mouse bone marrow were not observed. ConclusionTherefore, Dryopteris crassirhizoma is non-genotoxic in a three standard battery of tests and the oral LD50 of Dryopteris crassirhizoma is >2000mg/kg.

In vitro and in vivo safety evaluation of Acer tegmentosum

Ethnopharmacological relevanceAcer tegmentosum, which contains salidroside and tyrosol, has been used for the treatment of hepatic disorders in eastern Asia. However, little is known about its safety. Aim of the studyTo determine the safety of Acer tegmentosum, we evaluated its acute oral toxicity and genotoxicity profiles. Materials and methodsSalidroside and tyrosol present in Acer tegmentosum were quantified using high-performance liquid chromatography. Acute oral toxicity testing of Acer tegmentosum was performed in rats. Genotoxicity of Acer tegmentosum was assessed by bacterial reverse mutation, chromosomal aberration, and bone marrow micronucleus tests. All the tests were conducted in accordance with the good laboratory practices. ResultsThe amounts of salidroside and tyrosol in Acer tegmentosum were found to be 85.01±1.21mg/g and 3.12±0.04mg/g, respectively. In the bacterial reverse mutation test, Acer tegmentosum increased the number of revertant Salmonella typhimurium TA98 colonies, regardless of metabolic activation by S9 mixture. In contrast, Acer tegmentosum application did not significantly increase the number of chromosomal aberrations in Chinese hamster ovary (CHO)-K1 cells and micronucleated polychromatic erythrocytes in mice. In the acute oral toxicity test, the median lethal dose (LD50) of Acer tegmentosum was found to be >2000mg/kg in rats. ConclusionTake together, Acer tegmentosum exhibits mutagenicity, which was evident from the bacterial reverse mutation test. Further studies are needed to identify the components responsible for such an effect and the underlying mechanisms.