Genotoxicity and 28-day repeated dose oral toxicity study of garlic essential oil in mice.

Background and aim: Garlic essential oil (GEO) isolated from Garlic (Allium sativum L.) exerts biological activities in disease prevention, particularly in metabolic and liver diseases, and is used for a dietary therapy for centuries. However, due to the side effects associated with the excessive consumption of GEO, there is a need to evaluate the safety of the GEO. Experimental procedure: Ames test using five Salmonella typhimurium strains (TA98, TA100, TA102, TA1535, and TA1537) and Chinese hamster ovary (CHO-K1) cells with or without metabolic activation (S9 system), and mammalian erythrocyte micronucleus test were used to assess the genotoxicity and clastogenic effects of GEO. A repeated dose of GEO (15, 25, and 50 mg/kg body weight, p.o.) were administrated to ICR mice for 28 days to ascertain the subacute toxicity of GEO. Results and conclusions: The results of the Ames test with or without S9 system indicated that GEO did not induce mutagenicity nor have clastogenic effects in CHO-K1 cells with or without S9 activation. Furthermore, GEO did not affect the ratio of immature to total erythrocytes or the number of micronuclei in immature erythrocytes of ICR mice after 24 and 48 h. In a 28-day oral toxicity assessment, GEO (15, 25, and 50 mg/kg body weight, p.o.)-fed ICR mice exhibited normal behaviors, mortality, body weight, daily intake, hematology, clinical biochemistry, and organ weight. GEO shows no genotoxicity, and the no-observed-adverse-effect level (NOAEL) for GEO is considered to be greater than 50 mg/kg bw/day orally for 28 days in mice.

Genotoxicity and 28-day oral toxicity studies of a functional food mixture containing maltodextrin, white kidney bean extract, mulberry leaf extract, and niacin-bound chromium complex.

Steady-fiber granule (SFG) is a functional food mixture that is composed of four major ingredients, resistant maltodextrin, white kidney bean (Phaseolus vulgaris) extract, mulberry leaf (Morus alba L.) extract, and niacin-bound chromium complex. This study focused on determining the safety of SFG. Genotoxicity and 28-day oral toxicity were evaluated. SFG did not induce mutagenicity in the bacterial reverse mutation assay using five Salmonella typhimurium strains (TA98, TA100, TA102, TA1535, and TA1537) in the presence or absence of metabolic activation (S9 system). SFG also did not induce clastogenic effects in Chinese hamster ovary cells with or without S9 treatment. Similarly, SFG did not induce genotoxicity in a micronucleus test conducted with mice. A dose-dependent 28-day oral toxicity assessment of SFG for rats revealed no significant effects on mortality, body weight, selected organ weights, and behavior. Evaluations of hematology, clinical biochemistry, and histopathology showed no adverse effects in rats treated with SFG. These results suggest that SFG has no significant mutagenic or toxic properties, and the no observed adverse effect level of SFG was defined as at least 5000 mg/kg/day orally for 28 days for male and female rats.

Gastroprotective potential against indomethacin and safety assessment of the homology of medicine and food formula cuttlebone complex.

Cuttlebone complex (CBC), a homology of medicine and food formula, is comprised of five herbal medicines (Endoconcha Sepiae, Radix Paeoniae Rubra, fresh ginger, Fructus Amomi, and Radix Glycyrrhizae) and two food ingredients (Zingiber zerumbet and chitosan). Herein, the gastroprotective potential against indomethacin and a safety assessment of CBC were investigated. In a gastroprotective model, CBC effectively decreased the indomethacin-increased gastric ulcerous lesions, and increased the indomethacin-decreased prostaglandin E2 levels in the gastric mucosa. In genotoxicity tests, CBC treatment did not increase the numbers of revertant colonies in five Salmonella typhimurium strains and chromosome aberrations in Chinese hamster ovary CHO-K1 cells, with or without S9 metabolic activation. The oral supplementation of CBC did not increase micronucleus formation in the peripheral blood of mice. In a subacute toxicity study, the body weight and blood biochemical parameters observed in CBC-treated rats were normal. In conclusion, CBC was considered as a non-toxic formula and could be used to remedy indomethacin-induced gastric damage.

Structure-based development of bacterial nitroreductase against nitrobenzodiazepine-induced hypnosis.

Nitrobenzodiazepine (NBDZ) is an addictive drug of the abused substances that causes severe neurological effects and even death. Bacterial type I nitroreductase NfsB (EC 1.5.1.34) has been reported to catalyze NBDZ into inactive metabolite 7-amino-benzodiazepine (7ABDZ) with promising activity, so as to become an attractive candidate for treatment of NBDZ overdose and addiction. Here, we investigate the nitroreduction of an NBDZ, flunitrazepam (FZ), by various mutants of NfsB designed from the solved crystal structure and characterize their in vitro and in vivo potency. Conformational changes occurred in the active site of N71S/F124W in contrast to the wild-type, including the flipping on the aromatic rings of W124 and F70 as well as the extension on the hydrogen bond network between flavin mononucleotide (FMN) and S71, which allow the significant enlargement in the active site pocket. In the complex structure of N71S/F124W and nicotinamide (NIA), stacking sandwich attractions of W124-FMN-NIA were also found, implying the importance of W124 in substrate accessibility. Consequently, N71S/F124W exhibited increased 7AFZ production in vitro with nearly no toxicity and reduced 50% sleeping time (hypnosis) in vivo. Taken together, we demonstrate for the first time that N71S/F124W can serve as an effective antidote for NBDZ-induced hypnosis and provide the molecular basis for designing NfsB and the like in the future.

Evaluation of genotoxicity of Antrodia cinnamomea in the Ames test and the in vitro chromosomal aberration test.

Antrodia cinnamomea is an expensive and highly valued folk medicinal fungus that grows only inside the rotten trunk of Cinnamomum kanehirae, an evergreen broad-leaved tree. This fungus has recently been used commercially in the formulation of nutraceuticals and functional foods in Taiwan. It has been used for centuries as a detoxificant in cases of food poisoning, diarrhea, vomiting, hepatic disease and various kinds of cancers. The present study investigated the effects of Antrodia cinnamomea on mutagenicity using a bacterial reverse mutation assay employing the Salmonella typhimurium strains TA97, TA98, TA100, TA102, and TA1535. The effects of Antrodia cinnamomea on chromosome structure were tested in Chinese hamster ovary (CHO) cells. Antrodia cinnamomea was not mutagenic in all bacterial strains and it was not genotoxic in CHO cells.

Rapid determination of aristolochic acids I and II in herbal products and biological samples by ultra-high-pressure liquid chromatography-tandem mass spectrometry.

Aristolochic acids (AAs) are a mixture of structural-related compounds, in which aristolochic acid I (AA I) and aristolochic acid II (AA II) are reported to be correlated with Aristolochic acid nephropathy (AAN). In this work, a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to determine AA I and AA II in herbal products and biological fluids. By using gradient elution with a mobile phase composed of a mixture of 10mM ammonium formate buffer (pH 3.0) and acetonitrile, AAs could be determined within 10 min. Under optimum UHPLC-MS/MS conditions, the limit of detections was 0.14 and 0.26 ng mL(-1) for AA I and AA II, respectively. Run-to-run repeatability and intermediate precision of peak area for AA I and AA II were less than 5.74% relative standard deviation (RSD). Accuracy was tested by spiking 10, 100 and 1000 ng mL(-1) in rat serum and the recoveries were within 76.5-92.9%. Matrix effects were within 78.8-127.7%. The developed method was successfully applied to determine AA I and AA II in several herbal products and to investigate their pharmacokinetic behavior in female Wister rats. The result shows that the developed UHPLC-MS/MS method is efficient, sensitive, and accurate for the determination of AA I and AA II in herbal products and biological samples.