Chemical Composition, Antioxidant, Genotoxique and Antigenotoxic Potentials of Phlomis Bovei De Noé Aerial Parts.

In the present work, chemical investigation of the aerial parts of Phlomis bovei de Noé an endemic species from Algeria, led to the isolation and identification of seven known compounds including five flavones glycosides: Chrysoeriol 7-O-(3''-(E et Z)-p-coumaroyl)-ß-glucoside (1), terniflorin (apigenin-7-O-(6''-E-p-coumaroyl)glucoside) (3), apigenin-7-O-(6''-(5'''-methoxy-coumaryl) glucoside (4), apigenin 7-O-(3″-p-coumaryl)glucoside (5), hispidulin-7-O-glucuronide (6) and two cinnamic acid derivatives: p-coumaric acid methyl ester (E et Z) (2), chlorogenic acid (7). Compound 4 is described for the first time in the species bovei de Noé, the genus Phlomis and the Lamiaceae family. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. Some pure compounds and extracts have been evaluated for their antioxidant activities through different methods: DPPH and ABTS assays as well as CUPRAC assay. Genotoxic and antigenotoxic activities of pure compounds were also evaluated in-vitro on Escherichia coli PQ37 cells by the SOS Chromotest.

Antioxidant, Antimutagenic, Tanning and Calpain Induction Activities of Methanolic Extract of Tunisian Plant (Moricandia Arvensis).

In this study, we investigate the potential of Moricandia arvensis methanol leaf extract (MeOHL) on calpain activity, melanin biosynthesis and DNA mutagenicity. Cytotoxic effect and measurement of reactive oxygen species (ROS) induced by lucigenin in colorectal cells (BE) were also determined. In addition, the chemical analysis of the extract was also studied and the chemical profile illustrates its content in para-hydroxybenzoic acid (p-HBA), a glycosylated kampferol (GK), a glycosylated kampferol with Rhamnose (GKR) and 19 amino acids (AAs). Our results showed that MeOHL extract enhanced a significant cytotoxic (max of IP = 89.23%) and antioxidant (max of IP=100%) activities. Furthermore, the tested extract stimulated calpain activity and significantly increased the production of intra (46 µg/mL cells) and extracellular melanin content (12.5µg/mL). Using Ames assay, the extract exhibits a significant inhibition of mutagenicity induced by methy-methane-sulfonate (MMS) (76.32%) as well as 2-aminoanthracene (2-AA) (91%) in the Salmonella thyphimurium TA104 assay system.

An aqueous extract of Limoniastrum guyonianum gall induces anti-tumor effects in melanoma-injected mice via modulation of the immune response.

The objectives of this study were to evaluate the in vitro and in vivo anti-tumor potential of the aqueous gall extract (G extract) from Limoniastrum guyonianum and to elucidate its immunological mechanisms, in part, by assessing its effects on the growth of transplanted tumors and the immune response in these tumor-bearing mice. Here, mice were inoculated with B16F10 mouse tumor cells and then treated intraperitoneally with G extract at 25 or 50 mg extract/kg BW for 7, 14, or 21 days. At each timepoint, effects of the extract on the tumor growth, splenocytes proliferation, NK cell activity, and CTL activity among splenocytes isolated from the mice were measured. G extract-induced tumor growth inhibition was associated with characteristic apoptotic changes in the tumor cells, like nuclear condensation. In addition, the extract inhibited melanin synthesis and tyrosinase activity among melanoma cells in a concentration-related manner. G extract did not only significantly inhibit the growth of the transplantable tumor, but also remarkably increased splenocytes proliferation and both NK and CTL activities in tumor-bearing mice. The extract was also seen to have promoted lysosomal activity of host macrophages and gave rise to enhanced cellular anti-oxidant activity in several cell types in mice.

Antioxidant, mutagenic and antimutagenic activities of an aqueous extract of Limoniastrum guyonianum gall.

An aqueous extract of Limoniastrum guyonianum gall (G extract) was tested on Salmonella typhimurium to assess its mutagenic and antimutagenic effects. This extract showed no mutagenicity when tested with S. typhimurium strain TA104 either with or without exogenous metabolic activation mixture (S9), whereas our findings revealed that the aqueous gall extract induced a mutagenic effect in S. typhimurium TA1538 when tested in the presence, as well as in the absence, of S9 activation mixture at the concentration of 500 µg/mL. Thus, the same concentration produced a mutagenic effect, when incubated with S. typhimurium TA100 in the presence of metabolic activation mixture. In contrast, our results showed a weak antimutagenic potential of the same extract against sodium azide in the presence of S. typhimurium TA100 and S. typhimurium TA1538 without metabolic activation (S9), whereas, in the presence of S. typhimurium TA104, we obtained a significant inhibition percentage (76.39%) toward 3.25 µg/plate of methylmethanesulfonate. Antimutagenicity against aflatoxin B1, 4-nitro-o-phenylene-diamine and 2-aminoanthracène was significant, with an inhibition percentage of, respectively, 70.63, 99.3 and 63.37% in the presence of, respectively, S. typhimurium TA100, S. typhimurium TA1538 and S. typhimurium TA104 strains at a concentration of 250 µg/plate after metabolic activation (S9). Antioxidant capacity of the tested extract was evaluated using the enzymatic (xanthine/xanthine oxidase assay) and the nonenzymatic (2,2-diphenyl-1-picrylhydrazyl) system. G extract exhibited high antioxidant activity.

Flavonoids products from Nitraria retusa leaves promote lymphoblastoid cells apoptosis.

In this report, the ethyl acetate extract and its major constituent, isorhamnetin 3-o-robinobioside (I3-O-Rob), from Nitraria retusa (N. Retusa) leaf extracts were evaluated for their ability to induce apoptosis in human lymphoblastoid cells (TK6). Apoptosis of TK6 cell line was carried out using DNA fragmentation, poly ADP-ribose polymerase (PARP) cleavage with reference to caspase-3 activity. These tested products, from N. Retusa, enhanced the apoptosis effects in the tested cancer cell line. This result was confirmed by DNA fragmentation and PARP cleavage indicating a release of caspase-3 level. Our results indicate that the original ethyl acetate extract and the I3-O-Rob have a great antiproliferative effect on human lymphoblastoid cells (TK6), which may be due to their involvement in the apoptotic pathway.

Isorhamnetin 3-O-robinobioside from Nitraria retusa leaves enhance antioxidant and antigenotoxic activity in human chronic myelogenous leukemia cell line K562.

BACKGROUND: In this report, the isorhamnetin 3-o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, were evaluated for their ability to induce antioxidant and antigenotoxic effects in human chronic myelogenous leukemia cell line. METHODS: Nitraria retusa products properties were carried out by firstly evaluating their effects against lipid peroxidation induced by H2O2, using the thiobarbituric acid reactive substances species (TBARS) assay, and proceeding to the assay of cellular antioxidant activity, then doing the comet assay. RESULTS: The isorhamnetin 3-o-robinobioside showed a protective effect against lipid peroxidation induced by H2O2. The same natural compound and ethyl acetate extract inhibited oxidation induced by 2,2'-azobis (2-amidinopropane) dihydrochloride in human chronic myelogenous leukemia cells with respectively 50% inhibitory concentration values of 0.225 mg/ml and 0.31 mg/ml, reflecting a significant antioxidant potential. The same two products inhibited the genotoxicity induced by hydroxyl radicals in the same human cell line (by 77.77% at a concentration of 800 µg/ml and by 80.55% at a concentration of 1000 µg/ml respectively). CONCLUSIONS: The isorhamnetin 3- o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, have a great antioxidant and antigenotoxic potential on human chronic myelogenous leukemia cell line K562.

Investigation of the apoptotic way induced by digallic acid in human lymphoblastoid TK6 cells.

BACKGROUND: The digallic acid (DGA) purified from Pistacia lentiscus. L fruits was investigated for its antiproliferative and apoptotic activities on human lymphoblastoid TK6 cells. METHODS: We attempt to characterize the apoptotic pathway activated by DGA. Apoptosis was detected by DNA fragmentation, PARP cleavage and by evaluating caspase activities. RESULTS: The inhibition of lymphoblastoid cell proliferation was noted from 8.5 µg/ml of DGA. The induction of apoptosis was confirmed by DNA fragmentation and PARP cleavage. We have demonstrated that DGA induces apoptosis by activating the caspase-8 extrinsic pathway. Caspase-3 was also activated in a dose dependent manner. CONCLUSION: In summary, DGA exhibited an apoptosis inductor effect in TK6 cells revealing thus its potential as a cancer-preventive agent.

Digallic acid from Pistascia lentiscus fruits induces apoptosis and enhances antioxidant activities.

The antioxidant and apoptotic activities of digallic acid, isolated from the fruits of Pistascia lentiscus, were investigated. The study demonstrated that digallic acid possessed pro-apoptotic effects, as shown by provoking DNA fragmentation of K562 cells. It also revealed a significant antioxidant potential and effective scavenging activity against 2,2-diphenyl-1-picrylhdrazyl (DPPH·) and O2·â» radicals, and reduced cupric ions. We conclude that this integrated approach to apoptotic and antioxidant assessment may be useful to maximize the beneficial effects associated with using P. lentiscus derivatives as medicinal and dietary compounds.

Leaf extracts from Nitraria retusa promote cell population growth of human cancer cells by inducing apoptosis.

BACKGROUND: In this report the phytochemical profile of Nitraria. Retusa (N. Retusa) leaf extracts were identified and their ability to induce apoptosis in human chronic myelogenous erythroleukaemia (K562) was evaluated. METHODS: Apoptosis of the human chronic myelogenous erythroleukaemia (K562) was evidenced by investigating DNA fragmentation, PARP cleavage and caspases 3 and 8 inducing activities, in the presence of N. retusa extracts. RESULTS: Our study revealed that the tested extracts from N. Retusa contain many useful bioactive compounds. They induced in a time-dependent manner the apoptosis the tested cancerous our cell line. This result was confirmed by ladder DNA fragmentation profile and PARP cleavage, as well as a release in caspase-3 and caspase-8 level. CONCLUSION: Our results indicate that the tested compounds have a significant antiproliferative effect which may be due to their involvement in the induction of the extrinsic apoptosic pathway.

Flavonoids and sesquiterpenes from Tecurium ramosissimum promote antiproliferation of human cancer cells and enhance antioxidant activity: a structure-activity relationship study.

Fractionation of the chloroformic extracts from Teucrium ramosissimum leaves resulted in the isolation of three flavonoids: genkwanin (1), cirsimaritin (2) and 4',7-dimethoxy apigenin (4) and one sesquiterpene: ß-eudesmol (3). The structures were determined using data obtained from (1)H and (13)C NMR spectra, as well as by various correlation experiments (COSY, HMQC and HMBC). The antioxidant activities of the isolated flavonoids from T. ramosissimum leaves were evaluated by measuring their ability to scavenge the radical ABTS(+) and through chemical assays: cupric reducing antioxidant capacity (CUPRAC), reducing power (RP) and ferric reducing antioxidant power (FRAP). Furthermore, the effects of T. ramosissimum isolated molecules, on inhibition of cell proliferation and induction of apoptosis in human leukemia cells, were also examined. Cirsimaritin showed the best activity in the ABTS assay with TEAC value 2.04µM, whereas apigenin and 4',7-dimethoxy apigenin exhibited the highest antioxidant activity using the CUPRAC, RP and FRAP assays with TEAC values 10.5, 1.39 and 0.71µM respectively. The cytotoxic activity revealed that the ß-eudesmol inhibited significantly the proliferation of K562 cells (IC(50)=20µg/ml).

Antioxidant and antigenotoxic properties of compounds isolated from Marrubium deserti de Noé.

In our continual course toward the valorization of traditionally used endemic flora through the analysis of its chemobiodiversity, the phytochemical analysis of aerial parts of Marrubium deserti de Noé was undertaken. Dichloromethane and methanol extracts led to the isolation of terpenoid derivatives among which two were new labdane diterpenes named marrulibacetal A and desertine, respectively. Six of them were known compounds (a mixture of the isomers cyllenin A and 15-epi-cyllenin A, marrubiin, marrulactone, marrulibacetal and ß-stigmasterol) and seven known phenolic compounds were also isolated: apigenin and several 7-O-substituted derivatives (apigenin-7-O-ß-neohesperidoside, apigenin-7-O-glucoside, terniflorin and apigenin-7-O-glucuronide) together with two phenylethanoid glucosides (acteoside and forsythoside B). The structures and relative configurations of the new compounds were elucidated by MS and a series of 1D and 2D NMR analyses. Some pure compounds have been evaluated for their antioxidant activities through different methods: DPPH and ABTS assays as well as CUPRAC assay. Genotoxic and antigenotoxic activities of extracts and pure compounds were also evaluated in vitro on Escherichia coli PQ37 cells by the SOS Chromotest. Some of the isolated compounds like phenylethanoid derivatives showed stronger antioxidant capacity than trolox and were also able to significantly inhibit ß-galactosidase induction caused by the mutagen agent nitrofurantoin.

Anti-lipid peroxidation and induction of apoptosis in the erythroleukaemic cell line K562 by extracts from (Tunisian) Rhamnus alaternus L. (Rhamnaceae).

Total oligomer flavonoids (TOF) enriched and ethyl acetate (EA) extracts from Rhamnus alaternus induce apoptotic death in human chronic myelogenous leukaemia K562 cell line, as demonstrated by gel electrophoresis, which demonstrates the characteristic ladder patterns of DNA fragmentation and the proteolytic cleavage of poly(ADP ribose) polymerase (PARP). The effect of R. alaternus extract in reducing oxidative stress was evaluated by anti-lipid peroxidation which was monitored by measuring malondialdehyde level in K562 cultured cells. The TOF and EA extracts were found to be effective to protect against lipid peroxidation. Their IC50 values were 196 and 273 µg mL⁻¹, respectively. These findings suggest that R. alaternus extracts exhibit potential antioxidant and proapoptotic properties.

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.

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.

Antimutagenic and antioxidant potentials of Teucrium ramosissimum essential oil.

The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4-nitro-o-phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro-blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical-scavenging activity was observed towards DPPH(.) and O2(.-). In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay.

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 microg/plate in the presence of TA102 strain) and 38% (at 10 microg/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 0.95mM trolox equivalent when tested by the ferric reducing/antioxidant method.

Phlomis mauritanica extracts reduce the xanthine oxidase activity, scavenge the superoxide anions, and inhibit the aflatoxin B1-, sodium azide-, and 4-nitrophenyldiamine-induced mutagenicity in bacteria.

Four extracts were prepared from the leaves of Phlomis mauritanica: lyophilized infusion, total oligomer flavonoids, methanol, and ethyl acetate extracts. The antimutagenic properties of these extracts were investigated by assessing the inhibition of the mutagenic effects of direct-acting mutagens such as sodium azide and 4-nitrophenylenediamine and indirect-acting mutagens like aflatoxin B1 (AFB1) using the Ames assay. The four extracts prepared from P. mauritanica strongly inhibit the mutagenicity induced by AFB1 in both Salmonella typhimurium TA 100 and TA 98 assay systems. Lyophilized infusion and methanol extracts at the dose of 250 microg per plate reduced AFB1 mutagenicity by 93% and 91%, respectively, in S. typhymurium strain TA 100. We examined also the antioxidant effect of these extracts by the enzymatic xanthine/xanthine oxidase assay. Result indicated that total oligomer flavonoids and ethyl acetate and methanol extracts were potent inhibitors of xanthine oxidase activity. In contrast, lyophilized infusion, total oligomer flavonoids, and methanol extracts exhibited a high degree of superoxide anion scavenging. Our findings emphasize the potential of P. mauritanica extracts to prevent mutations and oxidant effects. Furthermore, the results presented here could be an additional argument to support the use of this species as a medicinal and dietary plant.

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.

Study of genotoxic, antigenotoxic and antioxidant activities of the digallic acid isolated from Pistacia lentiscus fruits.

The digallic acid obtained from the fruit Pistacia lentiscus exhibits an inhibitory activity against nitrofurantoine and B[a]P induced genotoxicity when tested by the SOS chromotest bacterial assay system in the presence of Escherichia coli PQ37 strain. The antioxidant activity of the tested compound was determined by its ability to scavenge the free radical ABTS(+), to inhibit the xanthine oxidase, involved in the generation of free radicals, and to inhibit the lipid peroxidation induced by H(2)O(2) in the K562 cell line. Our results revealed that digallic acid shows an important free radical scavenging activity towards the ABTS(+) radical (99%) and protection against lipid peroxidation (68%).

Leaf and root extracts of Moricandia arvensis protect against DNA damage in human lymphoblast cell K562 and enhance antioxidant activity.

Four extracts were prepared from the roots and leaves of Moricandia arvensis: root chloroform extract (ChlR), leaf chloroform extract (ChlL), root ethyl acetate extract (EAR) and leaf ethyl acetate extract (EAL). The genotoxic and antigenotoxic properties of these extracts were investigated by assessing the induction and inhibition of the genotoxicity induced by the direct-acting mutagen, hydrogen peroxide (H(2)O(2)), using the "Comet assay." It appears that none of the different extracts produces a genotoxic effect, except the highest tested concentrations of the leaf extracts which were capable to eliciting DNA damage. Human lymphoblast cells K562 were pretreated with different concentrations of each extracts and then treated by H(2)O(2), for the antigenotoxic study. The results showed that all extracts inhibited the genotoxicity induced by H(2)O(2) and particularly ChlR (42.5µg/ml) and ChlL (65µg/ml) extracts. In addition, antioxidant potential study of root and leaf extracts using different antioxidant tests indicated that root extracts possess a potent antioxidant activity through namely their capacity to transfer electrons.