Mutagenic,antimutagenic and antioxidant potency of leaf extracts from Nitraria retusa

Four extracts were prepared from the leaves of Nitraria retusa; methanol, ethyl acetate, chloroform and hexane extracts. An assay for the ability of these extracts to prevent mutations induced by various oxidants in Salmonella typhimurium TA102 and TA 104 strains was conducted. These extracts from leaf parts of N. retusa showed no mutagenicity either with or without the metabolic enzyme preparation (microsome fraction). The highest protection against methylmethanesulfonate induced mutagenicity was observed with chloroform and methanol extracts with inhibition percentages of 44.93% (at 50 μg/plate in the presence of TA102 strain) and 38% (at 10 μg/plate in the presence of TA104 strain), respectively. Whereas Hexane and chloroform extracts reduced the mutagenicity induced by 2-aminoanthracene by 83.4% (using the S. typhimurium TA104 assay system) and 65.3% (using the S. typhimurium TA 102 assay system), respectively. Antioxidant activity of N. retusa extracts was determined by the ability of each extract to protect plasmid DNA against strand scission induced by hydroxyl radicals. Chloroform extract exhibited the highest ability to protect plasmid DNA against hydroxyl radical induced DNA damages and exhibited the highest antioxidant capacity, with 0.95 mM trolox equivalent when tested by the ferric reducing/antioxidant method.     

Investigation of extracts from (Tunisian) Cyperus rotundus as antimutagens and radical scavengers

This study evaluates mutagenic and antimutagenic effects of aqueous, total oligomers flavonoïds (TOF), ethyl acetate and methanol extracts from aerial parts of Cyperus rotundus with the Salmonella typhimurium assay system.The different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA98, TA100, TA1535 and TA1538 either with or without the S9 mix. On the other hand, our results showed that all extracts have antimutagenic activity against Aflatoxin B1 (AFB1) in TA100 and TA98 assay system, and against sodium azide in TA100 and TA1535 assay system. TOF, ethyl acetate and methanol extracts exhibited the highest inhibition level of the Ames response induced by the indirect mutagen AFB1. Whereas, ethyl acetate and methanol extracts exhibited the highest level of protection towards the direct mutagen, sodium azide, induced response. In addition to antimutagenic activity, these extracts showed an important free radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. TOF, ethyl acetate and methanol extracts showed IC₅₀ value of 15, 14 and 20 μg/ml, respectively.Taken together, our finding showed that C. rotundus exhibits significant antioxidant and antimutagenic activities.     

Investigation of extracts from (Tunisian) Cyperus rotundus as antimutagens and radical scavengers

This study evaluates mutagenic and antimutagenic effects of aqueous, total oligomers flavonoïds (TOF), ethyl acetate and methanol extracts from aerial parts of Cyperus rotundus with the Salmonella typhimurium assay system.

The different extracts showed no mutagenicity when tested withSalmonella typhimurium strains TA98, TA100, TA1535 and TA1538 either with or without the S9 mix. On the other hand, our results showed that all extracts have antimutagenic activity against Aflatoxin B1 (AFB1) in TA100 and TA98 assay system, and against sodium azide in TA100 and TA1535 assay system. TOF, ethyl acetate and methanol extracts exhibited the highest inhibition level of the Ames response induced by the indirect mutagen AFB1. Whereas, ethyl acetate and methanol extracts exhibited the highest level of protection towards the direct mutagen, sodium azide, induced response. In addition to antimutagenic activity, these extracts showed an important free radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. TOF, ethyl acetate and methanol extracts showed IC₅₀ value of 15, 14 and 20 μg/ml, respectively.

Taken together, our finding showed that C. rotundus exhibits significant antioxidant and antimutagenic activities.     

Antioxidant and antigenotoxic activities in Acacia salicina extracts and its protective role against DNA strand scission induced by hydroxyl radical

The antioxidant potency of Acacia salicina extracts was investigated. Total antioxidant capacity was determined using an ABTS⁺ assay. Superoxide radical scavenging was measured using riboflavin-light-nitro blue tetrazolium (NBT) assay. In addition, the content of phenols, total flavonoids and sterols were measured in the tested extracts. The petroleum ether exhibited a potent scavenging activity toward ABTS radical cations. Whereas, chloroform extract showed the highest activity against superoxides radicals and was also able to protect pKS plasmid DNA against hydroxyl radicals induced DNA damages. The antimutagenicity of these extracts was assayed using the Ames assay against Salmonella typhimurium TA98 and S. typhimurium TA 1535 tester strains at different concentrations. These extracts decreased significantly the mutagenecity induced by sodium azide (SA) and 4-nitro-o-phenylenediamine (NOP). The antioxidant and antimutagenecity activities exhibited by A. salicina depended on the chemical composition of the tested extracts.     

Investigation of biological activity of polar extracts isolated from Phlomis crinita Cav ssp. mauritanica Munby

The lyophilized infusion, the methanol, the ethyl acetate, and the total oligomer flavonoid (TOF)-enriched extracts prepared from the dried leaves of Phlomis crinita Cav. ssp. mauritanica Munby were investigated for the contents of flavonoids, tannins, coumarines and steroids. Antibacterial activity was investigated toward five bacterial strains. An inhibitory effect was observed against Staphyllococcus aureus and Enterococcus feacalis, and the minimal inhibitory concentrations ranged from 2.5 to 5 mg/mL of extract. The tested extracts exhibit an important free radical scavenging activity toward the 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical; with IC₅₀ values of 30.5, 6, 32, and 31.5 μg/mL, respectively, in the presence of lyophilized infusion, the TOF, the methanol, and the ethyl acetate extracts. Genotoxic and antigenotoxic properties of the different extracts were studied by using the SOS chromotest with Escherichia coli PQ37. The lyophilized infusion and TOF extracts obtained from P. crinita ssp. mauritanica showed no genotoxicity, whereas methanol and ethyl acetate extracts are considered as marginally genotoxic. On the other hand, we showed that each extract inhibited the mutagenicity induced by aflatoxin B1 (AFB1) (10 μg/assay) and nifuroxazide (NF) (10 μg/assay). The ethyl acetate extract showed the strongest level of protection toward the genotoxicity induced by both directly and indirectly genotoxic NF and AFB1. These tests proved that the lyophilized infusion possesses an antiradical activity likewise, it showed no genotoxic effect; that is why we choose this extract to assess its antiulcerogenic activity by using an ethanol-induced ulcerogenesis model in the rat. This test demonstrates that 300 mg/kg of a P. crinita ssp. mauritanica lyophilized infusion was more effective than the reference compound, cimetidine.     

Diminution of free radical induced DNA damage by extracts/fractions from bark of Schleichera oleosa (Lour.) Oken

The present study was undertaken to investigate the effect of extracts of Schleichera oleosa (Sapindaceae) for its cytotoxic and hydroxyl radical-scavenging activities. The bark of the tree was used to prepare extracts with different solvents (i.e., hexane, chloroform, ethyl acetate, methanol, and water). The extracts were initially assessed for their in vitro cytotoxicity potential in the sulforhodamine B dye assay against cell lines, such as 502713 (colon), SW-620 (colon), HCT-15 (colon), A-549 (lung), HEP-2 (liver), SK-NS-H (central nervous system), and IMR-32 (neuroblastoma). It was observed that the water extract was effective against all the three colon cancer cell lines, while only methanol and water extracts were effective against A-549 (lung) and HEP-2 (liver), respectively. As DNA damage is one of the hallmarks of cell death, so the extracts were assessed for their ability to scavenge hydroxyl radicals, in the deoxyribose degradation assay (site- and nonsite specific) as well as their protective effect against the hydroxyl radical–induced DNA damage in the plasmid nicking assay, using pBR322. It was observed that all the extracts, except chloroform and hexane, exhibited relatively greater antioxidant activity in the nonsite-specific than in the site-specific assay. Similarly, the extracts were also found to be effective in inhibiting the hydroxyl radical–induced unwinding of supercoiled DNA, which further confirmed the hydroxyl radical–scavenging ability of the extracts in the deoxyribose degradation method.     

Assessment of isorhamnetin 3‐O‐neohesperidoside from Acacia salicina: protective effects toward oxidation damage and genotoxicity induced by aflatoxin B1 and nifuroxazide

Antioxidant activity of isorhamnetin 3‐O‐neohesperidoside, isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit xanthine oxidase activity and to scavenge the free radical 2,2′‐azino‐bis (3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS^.?) diammonium salt. Antigenotoxic activity was assessed using the SOS chromotest assay. This compound has the ability to scavenge the ABTS^.+ radical by a hydrogen donating mechanism. We also envisaged the study of the antioxidant effect of this compound by the enzymatic xanthine/xanthine oxidase (X/XOD) assay. Results indicated that isorhamnetin 3‐O‐neohesperidoside was a potent inhibitor of xanthine oxidase and superoxide anion scavengers. Moreover, this compound induced an inhibitory activity against nifuroxazide and aflatoxine B1 (AFB1) induced genotoxicity. Taken together, these observations provide evidence that isorhamnetin 3‐O‐neohesperidoside isolated from the leaves of A. salicina is able to protect cells against the consequences of oxidative stress. Copyright © 2010 John Wiley & Sons, Ltd.     

Chemical composition and biological investigation of Pelargonium endlicherianum root extracts

Context: Pelargonium endlicherianum Fenzl. (Geraniaceae) roots and flowers are traditionally used in Turkey as a decoction treatment against intestinal parasites. Neither the chemical composition nor the potential bioactivity of the plant roots has been studied before.

Objectives: The phenolic content and effects of P. endlicherianum root extracts on antioxidant enzyme levels on A549 cells were studied for the first time.

Materials and methods: The chemical composition was analyzed via spectrophotometric and chromatographic (HPLC MS/MS and HPLC) techniques. The antioxidant activity was determined at different concentrations ranging from 0.001 to 2?mg/mL using DPPH^? and ABTS^?+ radical scavenging activity, β-carotene-linoleic acid co-oxidation assay, protection of 2-deoxyribose and bovine brain-derived phospholipids against a hydroxyl radical-mediated degradation assay. Glutathione peroxidase and superoxide dismutase activities were also studied as well as the effects of the extracts on nitric oxide levels on IL-1β stimulated A549 cells.

Results: The key parameters for the most active ethyl acetate extract included the following: DPPH^? IC₅₀: 0.23?mg/mL, TEAC/ABTS: 2.17?mmol/L Trolox, reduction: 0.41?mmol/g AsscE, and protection of lipid peroxidation IC₅₀: 0.05?mg/mL. Furthermore, the ethyl acetate extract increased the SOD level significantly compared to control group (4.48?U/mL) at concentrations of 100 and 200?μg/mL SOD, 5.50 and 5.67?U/mL, respectively. Apocynin was identified as the major component, and the ethyl acetate fraction was found to be rich in phenolic compounds.

Discussion and conclusion: Pelargonium endlicherianum root extracts displayed antioxidant activity and increased the antioxidant enzyme levels in IL-1β stimulated A549 cells, while decreasing the NO levels.     

Leaf extracts from Moricandia arvensis promote antiproliferation of human cancer cells,induce apoptosis,and enhance antioxidant activity

The in vitro antiproliferative, apoptotic, and antioxidant activities from leaf extracts of Moricandia arvensis, which are used in traditional cooking and medicines, were investigated. The MTT assay revealed that only TOF (total oligomer flavonoids), ethyl acetate (EA), chloroform (Chl), and petroleum ether (PE) extracts inhibited the proliferation of K562 cells. Apoptosis plays a very important role in the treatment of cancer by promoting the apoptosis of cancer cells and limiting the concurrent death of normal cells. Thus, the possible effects of M. arvensis extracts on the induction of apoptosis in human leukemic cells (K562 cells) were investigated. The electrophoretic analysis of DNA fragmentation confirms that TOF, Chl, PE, and EA extracts provoke DNA fragmentation. Using the lipid peroxidation inhibitory assay, the antioxidant capacity of M. arvensis extracts was evaluated by the ability of each extract to inhibit malondialdehyde formation. It was revealed that EA and TOF extracts are the most active in scavenging the hydroxyl radicals.     

Mutagenic,Antimutagenic, Cytotoxic,and Apoptotic Activities of Extracts from Pituranthos tortuosus

Mutagenic and antimutagenic activities against direct acting mutagens, nifuroxazide (NF) and sodium azide (SA), and indirect acting mutagen aflatoxin B1 (AFB1) of extracts prepared from aerial parts of Pituranthos tortuosus were investigated in bacterial assay systems (i.e., the Ames test with Salmonella typhimurium TA100, TA98, TA1538, TA1535, and the SOS chromotest with Escherichia coli PQ 37). It was found that all extracts obtained from P. tortuosus decreased the mutagenicity induced by AFB1 (10 μg/assay), SA (1.5 μg/assay), and NF (20 μg/assay). Ethyl acetate, acetone, methanol, and total oligomer flavenoid extracts exhibited the highest inhibition level of mutagenicity induced by the indirect mutagen AFB1. In addition, antiproliferative and apoptotic properties of these extracts have also been reported using two leukemia cell lines, L1210 and K562. The results revealed that all extracts showed a significant cytotoxic effect on these cell lines, and the effect was greater in the presence of human K562 chronic myelogenous leukemia cells, whereas they do not induce apoptosis.     

Hydroxyl scavenging activity accounts for differential antioxidant protection of Plantago major against oxidative toxicity in isolated rat liver mitochondria

Objectives The aim of this work was to study the effects of P. major against the oxidative damage of isolated rat liver mitochondria. Methods The extracts were obtained using methanol (MeOH), ethyl acetate (EAc), dichloromethane (DCM), and hexane (Hex) as solvents. Key findings Hex, DCM, and EAc totally, and MeOH partially, inhibited ROS generation and lipid peroxidation of membranes induced by Fe²⁺ or t‐BOOH. However, only MeOH was able to prevent the t‐BOOH‐induced glutathione and NAD(P)H oxidation. All extracts chelated Fe²⁺ and reduced DPP Hradicals. EPR analysis revealed that P. major exhibited potent scavenger activity for hydroxyl radicals. Conclusions The potent antioxidant activity exhibited by P. major was able to prevent oxidative mitochondrial damage, contributing to the understanding of its hepatoprotective action against ROS‐mediated toxicity.     

Mutagenic activity promoted by amentoflavone and methanolic extract of Byrsonima crassa Niedenzu

Byrsonima crassa is a plant pertaining to the Brazilian central savannah-like belt of vegetation and popularly used for the treatment of gastric dysfunctions and diarrhoea. The methanol extract contains catechin, tannins, terpenes and flavonoids; both mutagenic potential and antioxidant properties have been ascribed to flavonoids. The mutagenicity of some flavonoids is believed to be associated with the formation of reactive oxygen species and seems to depend on the number and position of hydroxyl groups. In the present study the mutagenic activity of the methanol, chloroform and 80% aqueous methanol extracts, as well as acetate and aqueous sub-fractions, of this medicinal plant were evaluated by Salmonella typhimurium assay, using strains TA100, TA98, TA102 and TA97a, and in mouse reticulocytes. The results showed mutagenic activity of the methanolic extract in the TA98 strain without S9, but no mutagenicity to mouse cells in any of the extracts. The acetate fraction showed strong signs of mutagenicity without S9, suggesting that in this enriched fraction were concentrated the compounds that induced mutagenic activity. The aqueous fraction showed no mutagenic activity. The TLC and HSCCC analyses of the acetate fraction with some standard compounds permitted the isolation of the quercetin-3-O-beta-D-galactopyranoside, quercetin-3-O-alpha-L-arabinopyranoside, amentoflavone, methyl gallate and (+)-catechin, of which only the amentoflavone exhibited positive mutagenicity to TA98 (+S9, -S9).     

Free radical scavenging activity and antiproliferative potential of <Emphasis Type="Italic">Polygonum cuspidatum</Emphasis> root extracts

Polygonum cuspidatum is widely used as a medicinal herb in Asia. In this study, ethanol and ethyl acetate extracts of P. cuspidatum root were assayed for their 1,1-diphenyl-2-hydrazyl (DPPH) and hydroxyl free radical scavenging activities, total phenolics content, protective effect against DNA damage, and antiproliferative activity on human lung cancer cells. The ethanol and ethyl acetate (lipophilic phase) extracts of P. cuspidatum had significant scavenging effects on DPPH and hydroxyl radicals. Total phenolics content of ethanol and ethyl acetate (lipophilic phase) extracts of P. cuspidatum were 276.78 ± 39.31 and 231.73 ± 5.04 mg/ml, respectively; both extracts protected against hydroxyl radical-induced DNA strand scission. Furthermore, the extracts of P. cuspidatum induced apoptosis and inhibited cell growth in A549 and H1650 cell lines, suggesting that P. cuspidatum root extracts exhibit an antiproliferative effect on human lung cancer cells.     

Antioxidant and antimutagenic potential of Psidium guajava leaf extracts

Fruits, vegetables and medicinal herbs rich in phenolics antioxidants contribute toward reduced risk of age-related diseases and cancer. In this study, Psidium guajava leaf extract was fractionated in various organic solvents viz. petroleum ether, benzene, ethyl acetate, ethanl and methanol and tested for their antioxidant and antimutagenic properties. Methanolic fraction showed maximum antioxidant activity comparable to ascorbic acid and butylated hydroxyl toluene (BHT) as tested by DPPH free radical scavenging, phosphomolybdenum, FRAP (Fe3?+?reducing power) and CUPRAC (cupric ions (Cu²⁺) reducing ability) assays. The fraction was analyzed for antimutagenic activities against sodium azide (NaN₃), methylmethane sulfonate (MMS), 2-aminofluorene (2AF) and benzo(a)pyrene (BP) in Ames Salmonella tester strains. The methanol extracted fraction at 80?μg/ml concentration inhibited above 70% mutagenicity. Further, phytochemical analysis of methanol fraction that was found to be most active revealed the presence of nine major compounds by gas chromatography–mass spectrometry (GC–MS). This data suggests that guava contains high amount of phenolics responsible for broad-spectrum antimutagenic and antioxidant properties in vitro and could be potential candidates to be explored as modern phytomedicine.     

Studies on cytotoxic, hydroxyl radical scavenging and topoisomerase inhibitory activities of extracts of Tabernaemontana divaricata (L.) R.Br. ex Roem. and Schult

In the present investigation, the cytotoxic, hydroxyl radical scavenging and topoisomerase inhibition activities of Tabernaemontana divaricata (Apocynaceae) were evaluated. The extracts from leaves of the plant were prepared with different solvents viz. chloroform, methanol, ethyl acetate and hexane. In, in vitro cytotoxicity assay, with cell lines viz HCT-15 (Colon), HT-29 (Colon), 502713 (Colon), MCF-7 (Breast), PC- 3 (Prostrate), it was observed that the ethyl acetate extract was effective against only one colon cell line (502713) at the lowest dose i.e. 10 micro g/ml, whereas the chloroform extract was effective against all the three colon cancer cell lines, at 30 microg/ ml. In order to evaluate the mechanism of cytotoxicity of these extracts, they were assessed for their ability to scavenge hydroxyl radicals in plasmid nicking assay with pBR322. It was observed that all the extracts effectively inhibited the unwinding of supercoiled DNA except hexane extract, which showed the least effect. Since the expression of topo enzymes is linked with cell proliferation so the extracts were also checked for topo I and topo II inhibitory activities. It was noticed that ethyl acetate extract selectively showed inhibition of topo II in topoisomerase II relaxation assay.     

Mutagenicity of Hypericum lysimachioides extracts

Hypericum (Hypericaceae) species are extensively used in several fields such as traditional medicine, food and crop protection. Despite its usage in many fields, the identification of the genotoxic potential of this herb is still incomplete. In this study, we evaluated genotoxic effects of the petroleum ether, hexane, ethyl acetate, and methanol extract of Hypericum lysimachioides Boiss. var. lysimachioides by Ames Salmonella/microsome test and SOS chromotest. The mutagenic activity of Hypericum lysimachioides var. lysimachioides extracts was investigated by using Salmonella typhimurium strains TA98 and TA100 and also the SOS chromotest with Escherichia coli PQ37 strain, with or without S9 metabolic activation. In this initial report we demonstrated that all extracts of H. lysimachioides var. lysimachioides showed significant mutagenic activity on both strains of Salmonella either with or without S9 mixture. No mutagenicity was found in the SOS chromotest either with or without S9 mixture. These results indicate a significant mutagenicity of the petroleum ether, hexane, ethyl acetate and methanol extracts of Hypericum lysimachioides var. lysimachioides in vitro. It can be suggested that quercetin and flavonol or their synergistic effects may be main mutagenic agents in the photopharmaceuticals Hypericum lysimachioides var. lysimachioides extract.     

Antigenotoxic and Free Radical Scavenging Activities of Extracts from Moricandia arvensis

This study evaluates genotoxic and antigenotoxic effects of extracts from leaves of Moricandia arvensis, which are used in traditional cooking and medicines. Extracts showed no genotoxicity when tested with the SOS Chromotest using E. coli PQ37 and PQ35 strains, except for the total oligomers flavonoids enriched extract. Petroleum ether and methanol extracts are the most active in reducing nitrofurantoin genotoxicity, whereas methanol and total oligomers flavonoids enriched extracts showed the most important inhibitory effect of H₂O₂ genotoxicity. In addition, these two extracts showed important free radical scavenging activity toward the DPPH^· radical, whereas the chloroform extract exhibited the highest value of TEAC against ABTS^+· radical.     

Antioxidant and antigenotoxic effects of rosemary (Rosmarinus officinalis L.) extracts in Salmonella typhimurium TA98 and HepG2 cells

In the present study the chemopreventive effects of water soluble AquaROX^® 15 and oil soluble VivOX^® 40 rosemary extracts against 4-nitroquinoline-N-oxide (NQNO) and 2-amino-3-methyl-3H-imidazo[4,5-F]quinoline (IQ) induced mutagenicity in the reverse mutation assays with Salmonella typhimurium TA98 and against t-butyl hydroperoxide (t-BOOH), benzo(a)pyrene (BaP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) induced DNA damage in HepG2 cells were studied, applying the comet assay. The results showed comparable protective effect of AquaROX and VivOX against oxidative DNA damage, whereas protection against indirect active genotoxic carcinogens was more efficient by VivOX.