Abstract:In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals' scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.

Mutagenic and antimutagenic activities of freeze dried fruit juices (FDFJ) ofTesting the mutagenic activity, onions were suspended in solution of different concentrations of FDFJ alone in tap water for 48 h. Thereafter, root tips were prepared and observed for dividing cells and chromosomal aberrations using a light microscope. Antimutagenicity screening was similar to the mutagenic evaluation, except that the solution of FDFJ was combined with 0.1% cylophosphamide-CP. Free radicals (2,2-diphenyl-1-picrylhyrazyl) scavenging activity of the FDFJ was tested using butylated hydroxylanisole (BHA) and butylated hydroxytoluene (BHT) as the standards and their phenolic contents were evaluated by comparing with gallic acid equivalents (GAE). The free radicals scavenging power of M. fragrans at 1 mg/ml was almost similar to that of BHA and BHT and its phenolic content was 21 ± 6.0 mg GAE/g, the highest among the tested juices. A. cepa cell division was inhibited in a dose-dependent manner by the FDFJ of M. fragrans, while the induced chromosomal aberrations were non dose dependent. The cytotoxicity and chromosomal aberrations of CP were suppressed throughout the tested concentrations of M. fragrans, unlike the effects of other four juices. These results suggest that the observed activities of FDFJ of M. fragrans may be due to the quantity and quality of phenolic compounds with antioxidant activity, suggesting its use in preventing the DNAdamaging effects of mutagens.

The role of diets in causing cancers necessitates the ongoing search for natural antimutagens of promising anticancer therapeutics. This study determined the potential anticancer efficacy of the leaf extract of Myristica fragrans (Houtt.). Methanol leaf extract of M. fragrans (Houtt.) alone was screened for mutagenicity in the bacterial reverse mutation (Ames) test, using the Salmonella typhimurium TA100 strain, the Allium cepa, and the mouse in vivo bone marrow micronucleus tests. The antimutagenicity of this extract against benzo[a]pyrene- and cyclophosphamide-induced mutations was evaluated. An antioxidant test on the extract was performed with 2,2-diphenyl-1-picrylhydrazyl, using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as the standards, whereas its phytochemicals were elucidated by following the gas chromatography/mass spectrometry protocol. In S. typhimurium (TA100), the mutagenicity ratio at 200,500 and 1,000 µg/well was >2. Cell division in the A. cepa root tips and mouse bone marrow was significantly (P ≤ 0.05) inhibited at 2,000 and 4,000 mg/kg, whereas the observed chromosomal aberrations and micronucleated polychromatic erythrocytes were non-dose-related and were insignificantly (P ≥ 0.05) different from the negative control. Inhibition of benzo[a]pyrene- and cyclophosphamide-induced mutagenicity by this extract was above 40%. Half-maximal inhibitory concentration of the extract in the antioxidant test was lower than that of BHA and BHT. Phytochemical compounds, possessing antioxidant activity, may be responsible for the observed effects, suggesting a strong antimutagenic activity of the MeOH leaf extract of M. fragrans, a necessary characteristic of a promising anticancer agent.

In the present study, the Allium cepa chromosome assay was employed as a preliminary test to investigate the mutagenic and antimutagenic potential of three plants, namely Clinacanthus nutans, Adhatoda vasica, and Carica papaya, used by traditional practitioners in Malaysia against a direct acting mutagen-Methyl Methanesulphonate (MMS). Onions were planted in various treatment groups: plant extract alone, treatment 1 (pre-treatment with MMS and transfer into plant extracts), and treatment 2 (mixture of MMS and plant extracts). The bulbs planted in the extract alone for cytotoxicity and mutagenicity assessment revealed that none of the extracts of the three plants except the 50 mg/kg of methanol extract of A. vasicawere cytotoxic to A. cepa cells, but a moderate level of mutagenicity was observed at 200 and 400 mg/kg of methanol extract of C. papaya and at 400 mg/kg of aqueous extract of C. nutans. Antimutagenic screening on the other hand revealed that all the extracts tested were able to reduce the percentage chromosomal aberration induced by MMS, both in treatment 1 and 2. Besides that, MMS-induced cell death was also observed to be reduced in onion root cells treated with the plant extracts. Therefore, taking all the results obtained into consideration, the order of the plant extracts with increasing suppressiveness against MMS was C. papaya < A. vasica < C. nutans.DOI: http://dx.doi.org/10.3329/icpj.v2i8.15588 International Current Pharmaceutical Journal, July 2013, 2(8): 131-140

Natural plant extracts offer a promising hope in the prevention/treatment of cancer arising from genetic mutations. This study evaluated in vitro and in vivo mutagenic and antimutagenic effects of aqueous fraction of Myristica fragrans (AFMF) leaves on TA100 strain of Salmonella typhimurium and Mus musculus (Male Swiss albino mice), respectively. The antioxidant activity of AFMF against 2,2-diphenyl-1-picrylhydrazyl (DPPH), total phenolic and flavonoid contents were determined, followed by its phytochemical elucidation using the Ultra Performance Liquid Chromatography technique (UPLC). The mutagenicity of AFMF at 4, 20, 50, 100, 200, 500, and 1000 µg/well was