Isolation and characterization of piceatannol producing bacteria from soil in Erzurum, Turkey.

Piceatannol, resveratrol's derivative, and a valuable polyphenol has managed to become one of the most remarkable candidate molecules for drug development research, with its high bioactive properties and higher stability. On the other hand, the very low amount of piceatannol in plants which are its natural source increases the cost and limits the commercialization possibilities of the product. To overcome this bottleneck, a limited number of studies have recently shown that it is possible to produce piceatannol from the resveratrol precursor much cheaper by regioselective hydroxylation catalyzed by bacteria isolated from the soil, and the search for new bacteria of similar nature in new ecosystems has gained popularity. The aim of our study, which was prepared within this framework, is the bacterial isolate with regioselective hydroxylation potential obtained as a result of selective isolation steps; determination of resveratrol hydroxylation potentials and piceatannol product yields, investigation of possibilities to increase piceatannol yield with optimization trials and identification of isolates with the highest yield. For this purpose, 200 bacterial isolates capable of resveratrol hydroxylation were obtained from soil samples taken from Erzurum (Turkey) and its surroundings by using selective media. In the continuation of the study; resveratrol hydroxylation trials were carried out with these isolates and 55 active isolates capable of producing piceatannol by regioselective hydroxylation were selected. Then, yield improvement studies of active isolates were carried out by using different carbon sources and optimizing the culture conditions. As a result, a culture collection was created by identifying the 6 most active bacterial isolates with commercialization potential using conventional and molecular methods. These are 4 Gram-positive (Rhodococcus sp., Rhodococcus erythropolis, Paeniglutamicibacter sp., Arthrobacter sp.) and 2 Gram-negative (Shinella sp., Ensifer adhaerens) bacterial isolates. As a result of the optimization studies, three of these isolates used phenol as a biocatalyst, while the other three increased the production yield of piceatannol by using 4-hydroxyphenylacetic acid.

Assessment of antimicrobial activity and In Vitro wound healing potential of ZnO nanoparticles synthesized with Capparis spinosa extract.

Agents that will accelerate wound healing maintain their clinical importance in all aspects. The aim of this study is to determine the antimicrobial activity of zinc oxide nanoparticles (ZnO NPs) ZnO nanoparticles obtained by green synthesis from Capparis spinosa L. extract and their effect on in vitro wound healing. ZnO NPs were synthesized and characterized using Capparis spinosa L. extract. ZnO NPs were tested against nine ATCC-coded pathogen strains to determine antimicrobial activity. The effects of different doses (0.0390625-20 µg/mL) of NPs on cell viability were determined by MTT assay. The effect of ZnO NPs doses (0.0390625 µg/mL, 0.078125 µg/mL, 0.15625 µg/mL, 0.3125 µg/mL, 0.625 µg/mL, 1.25 µg/mL) that increase proliferation and migration on wound healing was investigated in an in vitro wound experiment. Cell culture medium obtained from the in vitro wound assay was used for biochemical analysis, and plate alcohol-fixed cells were used for immunohistochemical staining. It was determined that NPs formed an inhibition zone against the tested Gram-positive bacteria. The ZnO NPs doses determined in the MTT test provided faster wound closure in in-vitro conditions compared to the DMSO group. Biochemical analyses showed that inflammation and oxidative status decreased, while antioxidant levels increased in ZnO NPs groups. Immunohistochemical analyses showed increased expression levels of Bek/FGFR2, IGF, and TGF-ß associated with wound healing. The findings reveal the antimicrobial effect of ZnO nanoparticles obtained using Capparis spinosa L. extract in vitro and their potential applications in wound healing.

In Vitro Genotoxic and Antigenotoxic Effects of Ten Novel Synthesized 4-Thiazolidinone Derivatives.

Heterocyclic compounds are found in a variety of drug molecules, and bioactive natural products. 4-Thiazolidinones (4-TZDs), which represent an important class of heterocyclic compounds, are of great interest today with their diverse bioactivities. In this study, ten novel 4-TZD derivatives (C1-C10) were synthesized, characterized by spectroscopic techniques, and their genotoxic, and antigenotoxic properties were investigated in vitro using the Ames Salmonella/microsome mutagenicity assay in the concentration range of 0.2-1.0 mM/plate. The results revealed that none of the compounds were mutagenic on the three different Salmonella typhimurium strains up to the highest concentration tested. Furthermore, in our study, C1, C4, C6, and C9 showed significant, ranging from moderate to strong, antigenotoxic effects against mutagen-induced DNA damage at relatively higher doses. Among these, C4 had the best potential to inhibit the number of revertant colonies induced by 9-aminoacridine (9-AA), with a maximum inhibition rate of 47.9 % for 1.0 mM/plate. As a result, preliminary knowledge about the safety of the use of ten novel synthesized 4-TZD compounds likely to exhibit many bioactivities was obtained in this study. In addition, the significant in vitro antimutagenic activity of some derivatives increases the importance of studies for the development of new pharmacological agents for cancer prevention.

In vitro genotoxicity assessment of biosynthesized zinc oxide nanoparticles.

There are various studies on the toxicological potentials of conventionally synthesized zinc oxide (ZnO) nanoparticles, which are useful tools for many medical applications. However, knowledge about the biologically synthesized ones is still limited. In this study, the potential of producing ZnO nanoparticles via a green synthesis method, which enables safer, environmentally, economical and controlled production by using the Symphoricarpos albus L. plant, was investigated. For this purpose, aqueous extract was obtained from the fruits of the plant and reacted with zinc nitrate precursor. Characterization of the synthesized product was carried out by SEM and EDAX analyzes. In addition, the biosafety of the product was also investigated by using the Ames/Salmonella, E. coli WP2, Yeast DEL, seed germination, and RAPD test systems. The results obtained from SEM studies showed that spherical nanoparticles with an average diameter of 30 nm were synthesized as a result of the reaction. EDAX findings confirmed that these nanoparticles were composed of Zn and O elements. On the other hand, according to the findings of the biocompatibility tests, the synthesized nanoparticle did not show any toxic and genotoxic effects up to a concentration of 640 µg/ml in any of the test systems. Accordingly, considering the findings of our study, it was concluded that the aqueous extract of S. albus fruits can be used for the green synthesis of ZnO nanoparticles, the products obtained successfully passed the biocompatibility tests in our study, and additionally, more comprehensive biocompatibility tests should be performed before industrial scale production.

Determination of toxicity and radioprotective properties of bacterial and fungal eumelanin pigments.

PURPOSE: Determination of the protective property of melanin, an organic polymer class consisting of phenolic and/or indolic compounds isolated from bacteria and fungi, against fast neutron radiation. To show that these melanin samples, which also have antioxidant and metal chelating properties, can be used as an active ingredient for a drug to be developed against neutrons used in nuclear research and medicine. MATERIALS AND METHODS: Bacterial and fungal media were prepared, and melanin pigments were produced and isolated. For molecular characterization of pigments, bacterial genomic DNA extraction, 16S rDNA gene amplification processes, and fungal genomic DNA extraction, ITS1, and ITS4 Gene Regions amplification were performed. The DEL assay was implemented to determine the genotoxicity properties of bacterial and fungal melanin pigments. Samples were prepared in a pad measuring 10 ml volume (60 × 15 mm) at a concentration of 0.2-1 microgram in 1% agarose gel for radiation-absorbed dose measurements. Absorption measurements were made using 241Am-Be fast neutron source and Canberra brand NP series BF3 gaseous detector to determine the neutron radiation absorption capacity of all samples. The results obtained to determine the absorption degrees of melanin samples were compared with paraffin and normal concrete, which are widely used in neutron radiation shielding studies. RESULTS: Melanin pigments were obtained using different bacteria and fungi strains. Afterwards, the fast neutron radiation absorption capacity of these purified pigments were determined. Compared to reference samples, these pigments were found to have slightly lower radiation absorbing ability. In addition to these experiments, cytotoxicity tests were carried out using the Yeast DEL assay technique to evaluate the potential for use of these organic pigments in fields such as medicine and pharmacology. According to the results obtained from the tests, it was determined that these melanin samples did not have any toxic effects. CONCLUSION: It was determined that these melanin samples have the potential to be used as a radioprotective drug active substance to protect the tissues and cells of people exposed to neutron radiation after a nuclear accident or nuclear war.Giving a drug that will be developed by using these active ingredients before or after people are exposed to a radiation environment can provide great benefits.

Investigation of radiation protective features of azadispiro derivatives and their genotoxic potential with Ames/Salmonella test system.

PURPOSE: Five different types of synthesized azadispiro derivatives have been analyzed for radiation absorption capacity and determined their potential to be exploited as substances for a drug to be developed against radiation has been investigated. MATERIAL AND METHODS: Fast neutron attenuation parameters like the effective mean free path, half-value layer (HVL), removal cross-sections, and neutron transmission number were found with the Monte Carlo simulation Geometry And Tracking (GEANT4) code. Gamma radiation absorption parameters, such as effective atom number (Zeff), mean free path (MFP), mass attenuation coefficient (MAC), and half-value layer (HVL) were theoretically determined with WinXCom software. Besides, the exposure build-up factor (EBF) was calculated by using GP fitting parameters. Neutron absorption dose rate was experimentally calculated with 241Am-Be fast neutron source which has 4.5 MeV of energy, 74 GBq activity, and portative BF3 neutron detector. Ames/Salmonella test systems were used for the genotoxic potentials of the azadispiro derivatives. RESULTS AND CONCLUSIONS: Experimental and theoretical results were checked with paraffin and High-Density Polyethylene. The results showed that Azadispiro derivatives have neutron radiation absorption capability close to paraffin and High-Density Polyethylene. The gamma radiation absorption properties for azadispiro derivatives have been investigated, and it has been observed that these materials can absorb gamma radiation. Ames/Salmonella assay was used to examine whether the derivatives had a genotoxic effect probability or not. The results showed that these derivatives were genotoxic and safe at test doses (up to 5 mM). Consequently, it has been understood that these azadispiro derivatives can be used as active and genotoxic safety ingredients in the production of a protective drug against both neutrons and gamma rays.

In Vitro Evaluation of Immunogenicity of Recombinant OMP25 Protein Obtained from Endemic Brucella abortus Biovar 3 as Vaccine Candidate Molecule Against Animal Brucellosis.

BACKGROUND: Brucellosis is a zoonotic disease that causes serious economic losses due to factors, such as miscarriages and decreased milk yield in animals. Existing live vaccines have some disadvantages, so effective vaccines need to be developed with new technological approaches. OBJECTIVE: The primary objectives of this study were the expression and purification of recombinant Omp25 fusion protein from B. abortus, and the evaluation of the effect of the Omp25 protein on cell viability and inflammatory response. METHODS: The omp25 gene region was amplified by a polymerase chain reaction and cloned into a Pet102/D-TOPO expression vector. The protein expression was carried out using the prokaryotic expression system. The recombinant Omp25 protein was purified with affinity chromatography followed by GPC (Gel Permeation Chromatography). The MTS assay and cytokine-release measurements were carried out to evaluate cell viability and inflammatory response, respectively. RESULTS: It was determined that doses of the recombinant Omp25 protein greater than 0.1 µg/mL are toxic to RAW cells. Doses of 1 µg/mL and lower significantly increased inflammation due to Nitric Oxide (NO) levels. ELISA results showed that IFN-γ was produced in stimulated RAW 264.7 cells at a dose that did not affect the viability (0.05 µg/mL). However, IL-12, which is known to have a dual role in the activation of macrophages, did not show a statistically significant difference at the same dose. CONCLUSION: Studies on cell viability and Th1-related cytokine release suggest Omp25 protein to be a promising candidate molecule for vaccine development.

Investigation of neutron and gamma radiation protective characteristics of synthesized quinoline derivatives.

PURPOSE: Quinoline is formed by various natural compounds, such as alkaloids from the cinchona plant, which exhibit various biological activities, and is an important building material for the development of new drugs. Quinoline can be used in anti-radiation drug development but radiation interaction properties must be determined. MATERIAL AND METHODS: In this study, six types of synthesized quinoline derivatives were used. Fast neutron removal cross-section, mean free path, half value layer and transmission number were theoretically determined by using GEometry ANd Tracking 4 and FLUktuierende KAskade simulation codes for neutron shielding. Neutron dose absorption rates were determined using the 241Am-Be fast neutron source and the Canberra NP series portable BF3 gas proportional neutron detector. Gamma radiation shielding parameters were determined by using WinXCom and PSY-X/PSD software. Additionally, the genotoxic potentials of the derivatives were assessed by using the Ames/Salmonella bacterial reversion assay. RESULTS AND CONCLUSIONS: Neutron shielding parameters such as removal cross-section, mean free path, half value layer and transmission number were theoretically determined for fast neutrons. To determine neutron absorption capacity of quinoline derivatives, neutron absorption, experiments were conducted. In addition, gamma radiation shielding parameters were calculated such as the mean free path (MFP), mass attenuation coefficient (µt), half value thickness layer (HVL) and effective atomic number (Zeff) in the energy range of 0.015-15 MeV. The results of the all quinoline derivatives have excellent fast neutron shielding power compared to ordinary concrete. In addition, all quinoline derivatives have been found to have the capacity to attenuate gamma radiation. Moreover, they absorb well in both types of radiation, do not cause secondary radiation, and they are genotoxically safe at the tested concentrations. This study has demonstrated that these products can be used as active ingredients for a drug to be developed against radiation.

Integration of molecular tools in microbial phosphate solubilization research in agriculture perspective.

Phosphorus (P) is the second most crucial nutrient for plant growth after nitrogen. However, its highly reactive nature causes formation of insoluble derivatives and limits uptake by the plant roots. The wide spread applications of P based chemical fertilizers cause detrimental effects on soil fertility, agricultural product quality and environment. In this regard, phosphate-solubilizing microorganisms (PSMs) stand out as the most remarkable and promising tools for the development of safer and sustainable technologies. As a result of this, many bacterial and fungal species with significant phosphate-solubilizing activity have been discovered by using the conventional screening methods. However, the growing need for the discovery of new strains of PSMs necessitates the replacement or support to the time-consuming conventional methods with techniques that are more sensitive, reliable, reproducible and less time consuming. In this context, molecular tools and techniques provide novel approaches for microbial phosphate solubilization research. Hence, in this review information on the molecular approaches for the PSMs research is provided and its importance explained. The review also discusses the genes related to phosphate solubilizing mechanisms and molecular tools for screening these genes.

Rapid Detection of Phosphate-Solubilizing Bacteria from Agricultural Areas in Erzurum.

In this study, the newly designed pqq gene-specific primer sets were used for determination of phosphate-solubilizing capabilities of bacterial isolates from the agricultural regions of Erzurum. The specificity of newly designed primer sets (PqqA2F/PqqA2R, Pqq5F/Pqq5R, PqqF2/PqqF2R) were tested against ten isolates, whose phosphate-solubilizing activities were initially proved by the conventional methods. Non-phosphate-solubilizing bacteria were also chosen as negative control. According to the results, five of ten phosphate-solubilizing bacteria with PqqA2F/PqqA2R, two of ten phosphate-solubilizing bacteria with Pqq5F/Pqq5R primer set, and one of ten phosphate solubilizing with PqqF2F/PqqF2R bacteria were successfully amplificated in the PCR assay and none of the non-phosphate-solubilizing bacteria was amplificated. Then, the molecular characterization of the active phosphate-solubilizing strains was done based on the partial 16S ribosomal RNA gene region sequence analysis method. Two isolates of Enterobacter sp., 1 Rhizobium sp., 1 Enterococcus sp., 1 Bacillus cereus, 1 Bacillus atrophaeus, 1 Bacillus aryabhattai, 1 Acinetobacter sp., 1 Pseudomonas japonica, and 1 Enterobacter cloacae were identified as active phosphate-solubilizing strains. Consequently, the results showed that this specific primer sets could be used as an economic, rapid, and useful tool for the detection of phosphate-solubilizing strains in the agricultural researches.

Vincristine combination with Ca+2 channel blocker increase antitumor effects.

In this study, it was aimed to determine the effects of Amlodipine, a calcium channel blocker and vincristine (VCR) an antineoplastic, on human neuroblastomas using different doses. The cytotoxicity assays of the study were performed using the MTT method depending on time and concentration. After obtaining the mixture (up to 85% for SH-SY5Y) and sufficient branches (cortex neurons), the cells were treated with amlodipine (10 µM) and vincristine (0.5, 1 and 2 µg) at different concentrations for 24 h. MTT assay was performed by the commercially available kit (Sigma Aldrich, USA). Cells were harvested, washed and stained with PI and Annexin V, respectively, according to the manufacturer's protocol (Biovision, USA). Than analyzes were carried out. The results were quite impressive. When amlodipine (10 µM) was administered alone there was little change compared to the control. However, all doses of amlodipine (10 µM) and vincristine (0.5, 1 and 2 µg) were greater than the deaths in the doses alone (0.5, 1 and 2 µg) of vincristine alone. (P < 0.05). As a result, the combination of vincristine and amlodipine is more effective than vincristine alone in reducing the viability of cancer cells.

Anti-mutagenic and Anti-oxidant Potencies of Cetraria Aculeata (Schreb.) Fr., Cladonia Chlorophaea (Flörke ex Sommerf.) Spreng. and Cetrelia olivetorum (Nyl.) W.L. Culb. & C.F. Culb.).

In this study, the mutagenic and anti-mutagenic effects of methanol extract of three lichen species (Cetraria aculeata, Cladonia chlorophaea and Cetrelia olivetorum) were investigated by using E. coli-WP2, Ames-Salmonella (TA1535 and TA1537) and sister chromatid exchange (SCE) test systems. The results obtained from bacterial test systems demonstrated that methanol extracts of three lichen species have strong anti-mutagenic potencies on TA1535, TA1537 strains and to a lesser extent on E. coli-WP2 strain. The anti-oxidant level of human lymphocytes cells was determined in order to clarify the mechanism underlying the anti-mutagenic effects of these lichen species. Co-treatments of 5, 10 and 20 µg/mL concentrations of these three lichen species with AFB decreased the frequencies of SCE and the level of MDA and increased the amount of SOD, GSH and GPx which decreased by aflatoxin. The findings of this work have clearly demonstrated that Cetraria aculeata, Cladonia chlorophaea and Cetrelia olivetorum have significant anti-mutagenic effects which are thought to be partly due to the anti-oxidant activities and the interaction capability of lichen extracts with mutagen agents (Sodium azide, acridin, N-methyl-N'-nitro-N-nitrosoguanidine and aflatoxin B1).

Genotoxic evaluation of newly synthesized iminothiazolidinones.

The current study was designed to assess the potential toxicological effects of newly synthesized iminothiazolidinones by employing Ames Salmonella, Escherichia coli WP2, Zea mays seed germination, and random amplified polymorphic DNA (RAPD) assay systems. The bacterial tester strains S. typhimurium TA1535, TA1537, TA1538, TA98, TA100, and E. coli WP2 uvrA were chosen to test the direct gene mutation inducing capabilities of the test materials in prokaryotic systems and Z. mays seeds for determination of potential toxicological effects in eukaryotic systems. OPA-3 and OPA-6 primers were used in the RAPD analysis to determine genotoxic activities on the eukaryotic genomes. According to the results, none of the test materials showed significant mutagenic activity on the bacterial tester strains at the chosen concentrations. Additionally, none of the tested compounds showed inhibition of the germination of Z. mays seeds. In contrast, the RAPD analysis results were inconsistent with the bacterial reversion assays and the seed germination assay results. All test materials significantly changed the RAPD profiles for OPA-3; however, only compound 5 showed a significant change for OPA-6 when compared with the control groups. In conclusion, the newly synthesized iminothiazolidinone derivatives (C1-C5) were determined as potentially genotoxic compounds and they should be checked with multiple toxicology test systems before further studies to determine their actual use.

The antioxidant and antigenotoxic potential of methanol extract of Cladonia foliacea (Huds.) Willd.

In this article, the genotoxic and antigenotoxic effects of methanol extract of of Cladonia foliacea (Huds.) Willd. (CME) were studied using WP2, Ames (TA1535 and TA1537), and sister chromatid exchange (SCE) test systems. The results of our studies showed that 5 µM concentration of aflatoxin B1(AFB1) changed the frequencies of SCE and malondialdehyde (MDA) levels, superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPx) activities. When 5 and 10 µg/mL concentrations of CME was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH, and GPx levels were increased. The extract CME did not show any mutagenicity on Ames (Salmonella typhimurium TA1535, TA1537) and WP2 (Escherichia coli) test systems. On the other hand, CME has antimutagenicity on the mentioned test systems. The results of this experiment have clearly shown that CME has a significant antioxidative and antigenotoxic effect, which is thought to be due to the antigenotoxic activities of antioxidant enzymes.

Chemical Composition and Antibacterial Activity of Essential Oils of Two Species of Lamiaceae against Phytopathogenic Bacteria.

In this study, we aimed to determine chemical composition and antibacterial activities of Satureja hortensis and Calamintha nepeta against to 20 phytopathogenic bacteria causing serious crop loss. The essential oils of S. hortensis and C. nepeta were isolated by the hydrodistillation method and the chemical composition of the essential oils were analyzed by GC-MS. The antibacterial properties of the essential oils were evaluated against 20 phytopathogenic bacteria through Disc diffusion assay and micro dilution assay. The results revealed that the essential oils of S. hortensis and C. nepeta have significant antibacterial activity. Furthermore, the findings of the study are valuable for future investigations focusing on the alternative natural compounds to control plant diseases.

Two antigenotoxic chalcone glycosides from Mentha longifolia subsp. longifolia.

CONTEXT: Mentha L. (Labiatae) species (mint) with their flavoring properties have been used in food industries for centuries. Besides they have a great importance in drug development and medicinal applications due to various bioactive compounds of several members of the genus. OBJECTIVE: The aim of this study was to isolate bioactive compounds with antimutagenic potential by bio-guided fractionation and determine their structures by spectroscopic methods. MATERIALS AND METHODS: The structural elucidation of the isolated compounds was done based on spectroscopic methods, including MALDI-MS, UV, IR, and 2D NMR experiments, and the bio-guided fractionation process was done by using the Ames/Salmonella test system. Henceforth, solely genotoxic and antigenotoxic potential of the new compounds were also confirmed up to 2 µM/plate by using the same test system. RESULTS: Two new chalcone glycosides: (ßR)-ß,3,2',6'-tetrahydroxy-4-methoxy-4'-O-rutinosyldihydrochalcone and (ßR)-ß,4,2',6'-tetrahydroxy-4'-O-rutinosyldihydrochalcone, were isolated from Mentha longifolia (L.) Hudson subsp. longifolia, together with known six flavonoid glycosides and one phenolic acid: apigenin-7-O-glucoside, luteolin-7-O-glucoside, apigenin-7-O-rutinoside, luteolin-7-O-rutinoside, apigenin-7-O-glucuronide, luteolin-7-O-glucuronide, rosmarinic acid. According to the antimutagenicity results, both new test compounds significantly inhibited the mutagenic activity of 9-aminoacridine in a dose-dependent manner at the tested concentrations from 0.8 to 2 µM/plate. (ßR)-ß,4,2',6'-Tetrahydroxy-4'-O-rutinosyldihydrochalcone showed the maximum inhibition rate as 75.94% at 2 µM/plate concentration. CONCLUSIONS: This is the first report that two new chalcone glycosides were isolated from Mentha longifolia subsp. longifolia and their antimutagenic potentials by using mutant bacterial tester strains. In conclusion, the two new chalcone glycosides showed a significant antigenotoxic effect on 9-aminoacridine-induced mutagenesis at tested concentrations.

Antigenotoxic potencies of a lichen species, Evernia prunastri.

In this article, the genotoxic and antigenotoxic effects of methanol extract of Evernia prunastri (Huds.) Willd. (MEP) were studied using WP2, Ames (TA1535 and TA1537) and sister chromatid exchange (SCE) test systems. The results obtained from bacterial test systems demonstrated that MEP has strong antimutagenic potencies on TA1537 and WP2 strains. The highest inhibition rates for MEP on TA1537 and WP2 strains were 37.70% and 69.70%, respectively. According to the SCE test system, MEP reduced the genotoxic effects of aflatoxin. In order to clarify the mechanism underlying the antigenotoxic effects of MEP, the antioxidants were determined. Cotreatments of 5, 10 and 20 µg/mL concentrations of MEP with aflatoxin B1 decreased the frequencies of SCE and the malondialdehyde level and increased amount of superoxide dismutase, glutathione and glutathione peroxidase which were decreased by aflatoxin. The data obtained from this work have clearly shown that MEP has significant antigenotoxic effects which are thought to be partly due to the antioxidant activities and antioxidant inducing capability of MEP. This is the first report indicating the antigenotoxic activities of MEP against several mutagen agents such as N-methyl-N'-nitro-N-nitrosoguanidine, acridin and aflatoxin.

Isolation of a flavonoid, apigenin 7-O-glucoside, from Mentha longifolia (L.) Hudson subspecies longifolia and its genotoxic potency.

Mentha is a medicinal and aromatic plant belonging to the Lamiaceae family, which is widely used in food, flavor, cosmetic and pharmaceutical industries. Recently, it has been found that the use of Mentha as a pharmaceutical source is based on its phytochemical constituents that have far been identified as tannins, saponins, phenolic acids and flavonoids. This study was designed to evaluate the mutagenic and antimutagenic activities of apigenin 7-O-glucoside (A7G), a flavonoid isolated from Mentha longifolia (L.) Hudson subspecies longifolia (ML). The possible antimutagenic potential of A7G was examined against mutagens ethyl methanesulfonate and acridine in an eukaryotic cell system Saccharomyces cerevisiae and sodium azide in Salmonella typhimurium TA1535 and 9-aminoacridine in S. typhimurium TA1537. According to our findings, any concentrations of the A7G used did not show mutagenic activity but exerted strong antimutagenic activities at tested concentrations. The inhibition rates for the Ames test ranged from 27.2% (S. typhimurium TA1535: 0.4 µM/plate) to 91.1% (S. typhimurium TA1537: 0.2 µM/plate) and for the yeast deletion assay from 4% to 57.7%. This genotoxicological study suggests that a flavonoid from ML owing to antimutagenic properties is of great pharmacological importance and might be beneficial to industries producing food additives, cosmetics and pharmaceuticals products.

Genotoxic, antigenotoxic and antioxidant properties of methanol extracts obtained from Peltigera horizontalis and Peltigera praetextata.

Now-a-days, there is a big need to reduce genotoxic effects of mutagenic and carcinogenic agents in environment, which are increased by the technological development. Lichens produce a wide variety of unique metabolites due to being in various extreme areas and being symbiotic organisms of fungi and algae. Therefore, this study was planned to search new sources having antimutagenic activity by researching two different lichen species and to determine whether their usage is safe. With this respect, the mutagenic and antimutagenic properties of methanol extracts of the lichens were determined by the bacterial reverse mutation and sister chromatid exchange assays. Furthermore, the malondialdehyde level, superoxide dismutase, glutathione and glutathione peroxidase activities against aflatoxin B1 were determined for understanding the ways in which the lichens showed their genotoxic properties.

Ultrasonic synthesis, characterization of ß-aminoketones by bismuth(III) triflate and determination of antigenotoxic properties.

Direct-type catalytic Mannich reaction for the synthesis of ß-aminoketones from cyclohexanone, substituted aromatic amines and aromatic or hetero-aromatic aldehydes has been applied in water with bismuth triflate under ultrasound. Good yields of the expected ß-aminoketones were obtained from available substrates, at room temperature in 1-2 hours. This study was designed to evaluate the mutagenic and antimutagenic potential of synthesized ß-aminoketones compounds using Ames/Salmonella and Escherichia coli WP2 bacterial reverse mutation assay systems.