Antigenotoxic effect of plant extracts

This report reviews our study of antigenotoxic compounds from medicinal and aromatic plants performed over several years. The studies of this type are aimed at understanding the protective mechanisms which may be relevant for the primary prevention of cancer and other mutation-related diseases. Antigenotoxic potential in this study is estimated with prokaryotic and eukaryotic tests measuring spontaneous and induced mutations, recombination, mutagenic repair, chromosomal aberrations and micronuclei. Our results indicate that monoterpenoids from sage act as modulators of DNA repair pathways, whereas sage antioxidants interfere with metabolic activation enzymes. The potential use of sage extracts in cancer prevention is discussed

Ispitivanje antivirusne aktivnosti ekstrakata žalfije Salvia officinalis L. (Lamiaceae)

In the present study, we examined cytotoxicity and extracellular and intracellular antiviral activity of frac­tionated extracts of wild and cultivated sage Salvia officinalis L. (Lamiaceae) in vitro using the WISH-VSV model system. Extracts were obtained by fractionating depigmented ethanol extracts of sage plants with supercritical CO2 at different pressures. Cytotoxicity was determined by examining cellular morphology in situ with the aid of a colorimetric micromethod and by cell staining with trypan blue. The fraction of distilled cultivated sage obtained at CO2 pressure of 300 bars and temperature of 60°C (149/3) was the most cytotoxic, with CTD10 44 μg/ml. That of non-distilled cultivated sage obtained at CO2 pressure of 500 bars and temperature of 100°C (144/5) was the least toxic (CTD10 199 μg/ml). Moreover, 144/5 had an antiviral effect at the intracellular level: when added 5 hours before VSV infection, it caused 100% reduction of CPE at concentrations of 99.5 and 199.0 μg/ml; when added after virus penetration had occurred, the same concentrations caused 35 and 60% reduction, respectively. The obtained results indicate that antiviral activity of 144/5 involves inhibition of the early steps of the virus infective cycle without a direct virucidal effect. Abbreviations: WISH - human amnion epithelial cells, VSV - vesicular stomatitis virus, HSV - herpes simplex virus, CPE - cytopathic effect, IS - selectivity index, TCID50 - tissue culture infective dose, CTD10 - 10% cytotoxic concentrations.U radu je ispitivana antiviralna aktivnost različito frakcionisanih ekstrakata divlje i gajene žalfije Salvia officinalis L. (Lamiaceae) u in vitro uslovima koristeći WISH-VSV model sistem. Ekstrakti su dobijeni frakcionisanjem depigmentisanog etanolnog biljnog ekstrakta pod različitim pritiskom CO2. Citotoksičnost je određivana praćenjem ćelijske morfologije in situ, i bojenjem ćelija sa tripan plavim. Frakcija gajene žalfije dobijena na CO2 pritisku od 300 bara i temperaturi od 60°C (149/3) je pokazala najveću citotoksičnost (CTD10 44 μg/ml). Frakcija nedestilisane gajene žalfije dobijena na CO2 pritisku od 500 bara i temperaturi od 100°C (144/5) je pokazala najmanju toksičnost (CTD10 199 μg/ml). Takođe, frakcija 144/5 je pokazala i antiviralni efekat na intracelularnom nivou: kada se ćelije tretiraju 5 sati pre VSV infekcije, redukcija CPE je bila 100% na koncentraciji od 99.5 i 199.0 μg/ml; kada se ćelije tretiraju posle ulaska virusa u ćeliju na istim koncentarcijama redukcija CPE iz­nosi 35% odnosno 60%. Dobijeni rezultati ukazuju da frakcija 144/5 ima antiviralnu aktivnost koja se ostvaruje krozinhibiciju ranih stupnjeva viralne infekcije bezdirektnog virucidalnog efekta

The Effects of Vitamin C on Oxidative DNA Damage and Mutagenesis

U mutagenezi i bolestima uzrokovanim mutacijom, a i pri pojavi raka, dolazi do oštećenja DNA zbog djelovanja reaktivnih kisikovih spojeva. Stoga je istraživanje antigenotoksične sposobnosti antioksidansa uvelike važno za zaštitu ljudskoga zdravlja. Vitamin C je poznat kao jaki antioksidans, a zabilježeno je i njegovo prooksidativno djelovanje. U ovom su radu istražena antigenotoksična svojstva vitamina C analizom nasljednih osobina E. coli K12, E. coli WP2 i S. cerevisiae D7, te komet testom S. cerevisiae. Da bi se izazvala oksidativna mutageneza, upotrijebljen je t-butil hidroperoksid (t-BOOH), a kidanje lanaca DNA u komet testu izazvano je vodikovim peroksidom (H2O2). Vitamin C je smanjio mutagenezu induciranu s t-BOOH u soju S. cerevisiae DT, kao i mutagenezu induciranu s t-BOOH u soju E. coli K12 koji je uspješan u popravku DNA te spontanu mutagenezu u soju E. coli K12 koji ima smanjenju sposobnost popravka krivo sparenih baza. Međutim, u soju E. coli K12, koji je nosio plazmid sa sekvencijama mikrosatelita, obrada vitaminom C izazvala je nestabilnost mikrosatelita. Vitamin C je imao mutageni utjecaj na soj WP2 oxyR, vjerojatno zbog njegovih prooksidativnih svojstava pojačanih u soju bez antioksidativne obrane. Komet testom kvasca dobiveni su proturječni rezultati; dok je mala koncentracija vitamina C (0,05 μM) inhibirala, velike koncentracije od 0,1 do10 μM pojačale su oksidativna oštećenja. Dobiveni rezultati pokazuju da vitamin C može imati antigenotoksični ili genotoksični učinak, ovisno o dozi, genetskim svojstvima i drugim eksperimentalnim uvjetima.DNA damage induced by reactive oxygen species is involved in mutagenesis and generation of mutation-related diseases, including cancer. Therefore, study of antigenotoxic potential of antioxidants is of great importance for protection of human health. Vitamin C is well known as a potent antioxidant, but its prooxidative effects have also been reported. In this work, antigenotoxic properties of vitamin C in E. coli K12, E. coli WP2 and S. cerevisiae D7 reversion assays, as well as in S. cerevisiae comet assay were examined. t-Butyl hydroperoxide (t-BOOH) was used to induce oxidative mutagenesis, and hydrogen peroxide (H2O2) was used to induce DNA strand breaks in the comet assay. Vitamin C reduced t-BOOH-induced and spontaneous mutagenesis in repair proficient and mismatch repair (MMR) deficient strains of E. coli K12 respectively, as well as t-BOOH-induced mutagenesis in S. cerevisiae D7 strain. However, in E. coli K12 strains that carry plasmid with microsatellite sequences, treatment with vitamin C slightly stimulated microsatellite instability. Vitamin C also showed mutagenic effects in WP2 oxyR strain, probably due to its prooxidative potential, amplified in the strain deficient in antioxidative defense. In the yeast comet assay, contradictory results were obtained: while low concentration (0.05 mM) of vitamin C inhibited oxidative damage, higher concentrations (0.1–10 mM) stimulated it. The obtained results indicate that vitamin C can exhibit antigenotoxic or genotoxic effects, depending on the dose, genetic background and other experimental conditions

Antimutagenic effect of essential oil of sage (Salvia officinalis L.) and its fractions against UV-induced mutations in bacterial and yeast cells

The inhibition of spontaneous and UV-induced mutations by essential oil (EO) of sage (Salvia officinalis L.) and its fractions F1-F5 containing different proportions of mono- and sesquiterpenes was studied with the Salmonella/microsome, E. coli K12, and S. cerevisiae D7 reversion assays. The EO, F1, and F2 exhibited antimutagenic potential against UV-induced mutations in all tests. Fractions F3 and F4 produced a toxic, mutagenic, or antimutagenic response, depend­ing on the test organism used. Reduction of spontaneous and UV-induced mutations by F5 was detected only in permeable strains of E. coli. The obtained results demonstrate antimutagenic activity of volatile sage terpenes and recommend them for further antimutagenesis and anticarcinogenesis studies

Comparative study on the antibacterial activity of volatiles from sage (Salvia officinalis L.)

Antibacterial activity of volatiles from sage against Gram-positive and Gram-negative bacteria from the ATCC collection was screened with the disk diffusion test. The essential oil and its fractions showed a significant antibacterial effect against S. aureus and B. subtilis. The minimum inhibitory concentrations were 1.25-2.5 μL/mL for S. aureus and 0.15-2.5 μL/mL for B. subtilis. The effect on S. aureus was bactericidal, while initial bactericidal effect on B. subtilis was impaired by the presence of a resistant fraction of the population, probably endospores. The results obtained with wild type and permeable strains of E. coli and S. typhimurium indicate that transport through the cell wall limits the antibacterial effect of sage volatiles

Antimutagenic Properties of Basil (Ocimum basilicum L.) in Salmonella typhimurium TA100

The use of dietary antimutagens and anticarcinogens has been seen as a promising approach to the protection of human health. Basil (Ocimum basilicum L.) is a well-known medicinal and aromatic plant, with a range of newly discovered biological activities possibly important for chemoprevention. In the preliminary experiments, toxic and mutagenic potential of essential oil (EO) from basil and pure substances: linalool, ß-myrcene and 1,8-cineole were tested using Salmonella typhimurium TA98, TA100 and TA102, with and without S9 mix (microsomal fraction of rat liver). No mutagenic effect of basil derivatives was detected in any tested strain. Antimutagenic effects of essential oil from basil and its pure constituents were further evaluated in the Ames test using S. typhimurium TA100. UVC irradiation and three chemical mutagens, 4-nitroquinoline-N-oxide (4NQO), 2-nitropropane (2-NP) and benzo(a)pyrene (B(a)P) were used to induce mutagenesis. All tested basil derivatives significantly reduced UV-induced mutations. The maximum inhibition was in the range of 64–77 %. Inhibitory potential against direct acting model mutagen/carcinogen 4NQO was similar to UV (52–67 %). In the presence of S9, EO and 1,8-cineole showed moderate inhibition of 2-NP induced mutagenesis, while the remaining two substances had no effect. Linalool exhibited high co-mutagenic effect with B(a)P, 1,8-cineole showed moderate inhibitory effect against B(a)P-induced mutations, while EO and ß-myrcene were ineffective

Antimutagena svojstva bosiljka (Ocimum basilicum L.) u soju bakterije Salmonella typhimurium TA100

The use of dietary antimutagens and anticarcinogens has been seen as a promising approach to the protection of human health. Basil (Ocimum basilicum L.) is a well-known medicinal and aromatic plant, with a range of newly discovered biological activities possibly important for chemoprevention. In the preliminary experiments, toxic and mutagenic potential of essential oil (EO) from basil and pure substances: linalool, ß-myrcene and 1,8-cineole were tested using Salmonella typhimurium TA98, TA100 and TA102, with and without S9 mix (microsomal fraction of rat liver). No mutagenic effect of basil derivatives was detected in any tested strain. Antimutagenic effects of essential oil from basil and its pure constituents were further evaluated in the Ames test using S. typhimurium TA100. UVC irradiation and three chemical mutagens, 4-nitroquinoline-N-oxide (4NQO), 2-nitropropane (2-NP) and benzo(a)pyrene (B(a)P) were used to induce mutagenesis. All tested basil derivatives significantly reduced UV-induced mutations. The maximum inhibition was in the range of 64–77 %. Inhibitory potential against direct acting model mutagen/carcinogen 4NQO was similar to UV (52–67 %). In the presence of S9, EO and 1,8-cineole showed moderate inhibition of 2-NP induced mutagenesis, while the remaining two substances had no effect. Linalool exhibited high co-mutagenic effect with B(a)P, 1,8-cineole showed moderate inhibitory effect against B(a)P-induced mutations, while EO and ß-myrcene were ineffective.Upotreba dijetetskih antimutagena i antikarcinogena ima obećavajuću ulogu u zaštiti ljudskoga zdravlja. Bosiljak (Ocimum basilicum L.) dobro je poznata medicinska i aromatična biljka koja ima širok raspon tek otkrivenih bioloških aktivnosti važnih za prevenciju raka. U početnim pokusima istražen je toksični i mutageni potencijal esencijalnog ulja (essential oil – EO) bosiljka i čistih spojeva: linalola, ß-mircena i 1,8-cineola, koristeći sojeve bakterija Salmonella typhimurium TA98, TA100 i TA102, s dodatkom mješavine S9 mix (mikrosomalne frakcije jetre štakora) ili bez nje. Mutagena aktivnost ekstrakta bosiljka nije dokazana niti u jednom ispitanom soju. Zatim je Amesovim testom istražena antimutagena aktivnost esencijalnog ulja bosiljka i njegovih čistih sastojaka s pomoću S. typhimurium TA100. Za induciranje mutageneze primijenjeni su UV-C zračenje i 3 kemijska mutagena, 4-nitrokinolin-N-oksid (4NQO), 2-nitropropan (2-NP) i benzo(a)piren (B(a)P). Svi ispitani ekstrakti bosiljka pokazali su značajno smanjenje mutageneze inducirane UV zračenjem, pri čemu je maksimum inhibicije iznosio 64-77 %. Potencijal inhibicije mutagenog/karcinogenog djelovanja 4NQO bio je sličan (52-67 %). U prisutnosti S9, esencijalno ulje i 1,8-cineol pokazali su umjerenu inhibiciju mutageneze inducirane pomoću 2-NP, dok preostala dva sastojka nisu utjecala na mutagenezu. Linalol je pokazao znatan učinak u prisutnosti B(a)P, 1,8-cineol je umjereno inhibirao B(a)P induciranu mutagenezu, dok EO i ß-mircen nisu imali utjecaja

Antimutagenic activity of essential oil and crude extract of Phlomis fruticosa

The present study was carried out to investigate the antimutagenic activity of essential oil and crude extract of Phlomis fruticosa. This species belongs to the family Lamiaceae which includes a number of species with medical and pharmaceutical properties. The Escherichia coli K12 reversion assay for identifying antimutagens was used. The number of spontaneous and UV-induced Arg(+) revertants, as well as cell survival was monitored in the presence of non-toxic concentrations of the essential oil. The number of UV-induced revertants was slightly increased in the presence of essential oil. The ethanol extract demonstrated a significant effect on viable cells. Study on pharmacological and phytochemical activities as well as antimutagenetic potential against some chemical mutagens of the essential oils, total extract and their different fractions and constituents of Ph. fruticosa is in progress.nul