Antimutagenic and free radical scavenger effects of leaf extracts from Accacia salicina

<p>Abstract</p> <p>Background</p> <p>Three extracts were prepared from the leaves of <it>Accacia salicina</it>; ethyl acetate (EA), chloroform (Chl) and petroleum ether (PE) extracts and was designed to examine antimutagenic, antioxidant potenty and oxidative DNA damage protecting activity.</p> <p>Methods</p> <p>Antioxidant activity of <it>A. salicina </it>extracts was determined by the ability of each extract to protect against plasmid DNA strand scission induced by hydroxyl radicals. An assay for the ability of these extracts to prevent mutations induced by various oxidants in <it>Salmonella typhimurium </it>TA102 and TA 104 strains was conducted. In addition, nonenzymatic methods were employed to evaluate anti-oxidative effects of tested extracts.</p> <p>Results</p> <p>These extracts from leaf parts of <it>A. salicina </it>showed no mutagenicity either with or without the metabolic enzyme preparation (S9). The highest protections against methylmethanesulfonate induced mutagenicity were observed with all extracts and especially chloroform extract. This extract exhibited the highest inhibitiory level of the Ames response induced by the indirect mutagen 2- aminoanthracene. All extracts exhibited the highest ability to protect plasmid DNA against hydroxyl radicals induced DNA damages. The ethyl acetate (EA) and chloroform (Chl) extracts showed with high TEAC values radical of 0.95 and 0.81 mM respectively, against the ABTS^.+.</p> <p>Conclusion</p> <p>The present study revealed the antimutagenic and antioxidant potenty of plant extract from <it>Accacia salicina </it>leaves.</p

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

<p>Abstract</p> <p>Background</p> <p>In this report the phytochemical profile of <it>Nitraria. Retusa (N. Retusa</it>) leaf extracts were identified and their ability to induce apoptosis in human chronic myelogenous erythroleukaemia (K562) was evaluated.</p> <p>Methods</p> <p>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 <it>N. retusa </it>extracts.</p> <p>Results</p> <p>Our study revealed that the tested extracts from <it>N. Retusa </it>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.</p> <p>Conclusion</p> <p>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.</p

Polar extracts from (Tunisian) Acacia salicina Lindl. Study of the antimicrobial and antigenotoxic activities

<p>Abstract</p> <p>Background</p> <p>Methanolic, aqueous and Total Oligomer Flavonoids (TOF)-enriched extracts obtained from the leaves of <it>Acacia salicina </it>'Lindl.' were investigated for antibacterial, antimutagenic and antioxidant activities.</p> <p>Methods</p> <p>The antimicrobial activity was tested on the Gram positive and Gram negative reference bacterial strains. The Mutagenic and antimutagenic activities against direct acting mutagens, methylmethane sulfonate (MMS) and 4-nitro-o-phenylenediamine (NOPD), and indirect acting mutagens, 2-aminoanthracene (2-AA) and benzo[a]pyrene (B(a)P) were performed with <it>S. typhimurium </it>TA102 and TA98 assay systems. In addition, the enzymatic and nonenzymatic methods were employed to evaluate the anti-oxidative effects of the tested extracts.</p> <p>Results</p> <p>A significant effect against the Gram positive and Gram negative reference bacterial strains was observed with all the extracts. The mutagenic and antimutagenic studies revealed that all the extracts decreased the mutagenicity induced by B(a)P (7.5 μg/plate), 2-AA (5 μg/plate), MMS (1.3 mg/plate) and NOPD (10 μg/plate). Likewise, all the extracts showed an important free radical scavenging activity towards the superoxide anion generated by the xanthine/xanthine oxidase assay system, as well as high Trolox Equivalent Antioxidant Capacity (TEAC), against the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS)⁺• radical. TOF-enriched extract exhibited the highest protective effect against free radicals, direct acting-mutagen and metabolically activated S9-dependent mutagens.</p> <p>Conclusions</p> <p>The present study indicates that the extracts from <it>A. salicina </it>leaves are a significant source of compounds with the antimutagenic and antioxidant activities, and this may be useful for developing potential chemopreventive substances.</p

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

<p>Abstract</p> <p>Background</p> <p>The digallic acid (DGA) purified from <it>Pistacia lentiscus</it>. L fruits was investigated for its antiproliferative and apoptotic activities on human lymphoblastoid TK6 cells.</p> <p>Methods</p> <p>We attempt to characterize the apoptotic pathway activated by DGA. Apoptosis was detected by DNA fragmentation, PARP cleavage and by evaluating caspase activities.</p> <p>Results</p> <p>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.</p> <p>Conclusion</p> <p>In summary, DGA exhibited an apoptosis inductor effect in TK6 cells revealing thus its potential as a cancer-preventive agent.</p

A comparative evaluation of mutagenic, antimutagenic, radical scavenging and antibacterial activities of essential oils of Pituranthos chloranthus (Coss. et Dur.)

International audienc

Antioxidant, genotoxic and antigenotoxic activities of daphne gnidium leaf extracts

<p>Abstract</p> <p>Background</p> <p>Plants play a significant role in maintaining human health and improving the quality of human life. They serve humans well as valuable components of food, as well as in cosmetics, dyes, and medicines. In fact, many plant extracts prepared from plants have been shown to exert biological activity <it>in vitro</it> and <it>in vivo</it>. The present study explored antioxidant and antigenotoxic effects of <it>Daphne gnidium</it> leaf extracts.</p> <p>Methods</p> <p>The genotoxic potential of petroleum ether, chloroform, ethyl acetate, methanol and total oligomer flavonoid (TOF) enriched extracts from leaves of <it>Daphne gnidium</it>, was assessed using <it>Escherichia coli</it> PQ37. Likewise, the antigenotoxicity of the same extracts was tested using the “SOS chromotest test”. Antioxidant activities were studied using non enzymatic and enzymatic method: NBT/Riboflavine and xantine oxidase.</p> <p>Results</p> <p>None of the different extracts produced a genotoxic effect, except TOF extract at the lowest tested dose. Our results showed that <it>D. gnidium</it> leaf extracts possess an antigenotoxic effect against the nitrofurantoin a mutagen of reference. Ethyl acetate and TOF extracts were the most effective in inhibiting xanthine oxidase activity. While, methanol extract was the most potent superoxide scavenger when tested with the NBT/Riboflavine assay.</p> <p>Conclusions</p> <p>The present study has demonstrated that <it>D. gnidium</it> leaf extract possess antioxidant and antigenotoxic effects. These activities could be ascribed to compounds like polyphenols and flavonoid. Further studies are required to isolate the active molecules.</p