Medine Gulluce

Antimicrobial activity of aqueous and methanol extracts of Juniperus oxycedrus L.

Aqueous and methanol extracts of the leaves of Juniperus oxycedrus were investigated for their in vitro antimicrobial properties. The plant was collected from Pelitli Village of Gebze, Kocaeli, in the Marmara region of Turkey. Juniperus oxycedrus is widely used as traditional folk medicine in Turkey for treatment of different infectious diseases. The antimicrobial activity of the extracts against 143 laboratory strains belonging to 56 bacterial species, and 31 isolates of 5 fungi species were evaluated based on the inhibition zone using the disc-diffusion assay, minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values. The aqueous extract of J. oxycedrus had no antimicrobial effect against the test microorganisms whereas the methanol extract had inhibitory effects on the growth of 57 strains of 24 bacterial species in the genera of Acinetobacter, Bacillus, Brevundimonas, Brucella, Enterobacter, Escherichia, Micrococcus, Pseudomonas, Staphylococcus, and Xanthomonas. In addition 11 Candida albicans isolates at a concentration of 31.25-250 micro g/ml were also inhibited.

Evaluation of antimicrobial activities of Satureja hortensis L.

The present study was designated to evaluate the antimicrobial activities of methonol and hexane extracts of Satureja hortensis L. which is an annual herb used as traditional folk medicine in Eastern Anatolia region of Turkey for the treatment of different infectious diseases and disorders. The antimicrobial activities of the extracts against 147 laboratory strains belong to 55 bacterial species, and 31 isolates of 1 yeast and 4 fungi species were tested by using disc diffusion assay. The results showed that hexane extract of Satureja hortensis had no antifungal, but antibacterial activity against four strains of three Bacillus species whereas methanol extract of Satureja hortensis had both anticandidal and antibacterial effects. It inhibited the growth of 23 strains of 11 bacterial species and 6 isolates of Candida albicans, at the concentration of 300microg/ml. Satureja hortensis did not show antimicrobial activity against the remaining microorganisms (83%) tested including most and all of the clinic and plant pathogenic microorganisms, respectively. Methanol extract showed stronger and broader spectrum of antimicrobial activity as compared to hexane extract.

Identification and characterization of thermophilic bacteria isolated from hot springs in Turkey

The present study was conducted to identify and characterize the thermophilic bacteria isolated from various hot springs in Turkey by using phenotypic and genotypic methods including fatty acid methyl ester and rep-PCR profilings, and 16S rRNA sequencing. The data of fatty acid analysis showed the presence of 17 different fatty acids in 15 bacterial strains examined in this study. Six fatty acids, 15:0 iso, 15:0 anteiso, 16:0, 16:0 iso, 17:0 iso, and 17:0 anteiso, were present in all strains. The bacterial strains were classified into three phenotypic groups based on fatty acid profiles which were confirmed by genotypic methods such as 16S rRNA sequence analysis and rep-PCR genomic fingerprint profiles. After evaluating several primer sets targeting the repetitive DNA elements of REP, ERIC, BOX and (GTG)(5), the (GTG)(5) and BOXA1R primers were found to be the most reliable technique for identification and taxonomic characterization of thermophilic bacteria in the genera of Geobacillus, Anoxybacillus and Bacillus spp. Therefore, rep-PCR fingerprinting using the (GTG)(5) and BOXA1R primers can be considered as a promising genotypic tool for the identification and characterization of thermophilic bacteria from species to strain level.

Characterization of Thermophilic Bacteria Using Surface-Enhanced Raman Scattering

Surface-enhanced Raman scattering (SERS) can provide molecular-level information about the molecules and molecular structures in the vicinity of nanostructured noble metal surfaces such as gold and silver. The three thermophilic bacteria Bacillus licheniformis, Geobacillus stearothermophilus, and Geobacillus pallidus, a Gram-negative bacterium E. coli, and a Gram-positive bacterium B. megaterium are comparatively characterized using SERS. The SERS spectra of thermophilic bacteria are similar, while they show significant differences compared to E. coli and B. megaterium. The findings indicate that a higher number of thiol residues and possible S–S bridges are present in the cell wall structure of thermophilic bacteria, providing their stability at elevated temperatures. Incubating the thermophilic bacteria with colloidal silver suspension at longer times improved the bacteria–silver nanoparticle interaction kinetics, while increased temperature does not have a pronounced effect on spectral features. A tentative assignment of the SERS bands was attempted for thermophilic bacteria. The results indicate that SERS can be a useful tool to study bacterial cell wall molecular differences.

Mutagenic and antimutagenic effects of hexane extract of some Astragalus species grown in the eastern Anatolia region of Turkey

Medical plants and their various extracts have been occasionally used in the treatment of many diseases. Astragalus is one of those medical plants and it has several biological activities. In the present study, the hexane extracts of six Astragalus species, which are grown in the eastern Anatolia region of Turkey, were isolated, and their mutagenic and antimutagenic properties were investigated by using Salmonella typhimurium TA1535, TA1537 and Escherichia coli WP2uvrA tester strains at 0.05, 0.5 and 5 μg/plate concentrations. Known mutagens sodium azide (NaN3), 9‐Aminoacridine (9‐AA) and N‐Methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG) were used to determine antimutagenic properties of hexane extracts. The results showed that all hexane extracts, investigated in the present study, can be considered genotoxically safe because they do not have mutagenic activity at the tested concentrations. But, a great many of them have antimutagenic activity against 9‐Aminoacridine known as a model intercalator agent. The inhibition rates obtained from the antimutagenicity assays ranged from 27.51% (A. macrocephalus – 0.05 μg/plate) to 54.39% (A. galegiformis – 5 μg/plate). These activities are valuable toward an extension of the employ of these drugs as new phytotherapeutic or preservative ingredients. Copyright

Antioxidant and Antimicrobial Properties of the Lichens Cladonia foliacea., Dermatocarpon miniatum., Everinia divaricata., Evernia prunastri., and Neofuscella pulla.

Abstract The aim of this study was to investigate in vitro. antimicrobial and antioxidant activities of the methanol extracts of Cladonia foliacea. Willd. Hudson, Dermatocarpon miniatum.(L.) Mann., Everinia divaricata. (L.) Ach., Evernia prunastri. (L.) Ach., and Neofuscella pulla. (Ach.) Essl. Antioxidant activity was evaluated by two separate methods: scavenging of free radical DPPH and the inhibition of linoleic acid oxidation. Extracts of C. foliacea., E. divaricata., E. prunastri., and N. pulla. did not exert any activity in both assays, whereas those of D. miniatum. provided 50% inhibition at 396.1 µg/ml concentration in the former and gave 49% inhibition in the latter. Total phenolic constituents of extracts from lichen species tested (C. foliacea., D. miniatum., E. divaricata., E. prunastri., and N. pulla.) were 1.7% (w/w), 2.9% (w/w), 3.0% (w/w), 2.6% (w/w), and 1.5% (w/w), respectively (as gallic acid equivalent), implying that the observed activity could be related to the amount of polar phenolics. Extracts were also found to possess antimicrobial activity against some of the bacteria and fungi tested, but no activity was observed against the yeasts.

Isolation of some luteolin derivatives from Mentha longifolia (L.) Hudson subsp. longifolia and determination of their genotoxic potencies

This study was designed to evaluate the mutagenic and antimutagenic activities of luteolin derivatives (luteolin 7-O-glucoside, luteolin 7-O-rutinoside and luteolin 7-O-glucuronide) isolated from Mentha longifolia (L.) Huds. subsp. longifolia by using Ames Salmonella test (TA 1535 and TA1537 strains). In the antimutagenicity assays, luteolin 7-O-glucoside, luteolin 7-O-rutinoside and luteolin 7-O-glucuronide showed antimutagenic effects on TA1537 and TA1535 strains. The highest inhibition rates for luteolin 7-O-glucoside, luteolin 7-O-rutinoside and luteolin 7-O-glucuronide on TA1537 strain were 84.03%, 87.63% and 67.77%, respectively. Similarly, in the antimutagenicity assays performed with the TA1535 strain, the inhibition rates for luteolin 7-O-glucoside and luteolin 7-O-rutinoside were 23.86% and 23.76% respectively. Our findings showed that the antimutagenic properties of luteolin derivatives on TA1537 and TA1535 strains have been found to be structure dependent. The clarification of differences in antimutagenic potency of these luteolin derivatives based on their structures has been demonstrated in this study.

Effects of Plant-Growth-Promoting Rhizobacteria on Yield, Growth, and Some Physiological Characteristics of Wheat and Barley Plants

In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) treatments, applied either alone or in combination, on yield, plant growth, leaf total chlorophyll content, stomatal conductance, membrane leakage, and leaf relative water content of wheat (Triticum aestivum L. cv. Bezostiya) and barley (Hordeum vulgare L. cv. Tokak) plants. Results showed that alone or combined B (0, 1, 3, 6, 9 kg ha−1) and PGPR (Bacillus megaterium M3, Bacillus subtilis OSU142, Azospirillum brasilense Sp245, and Raoultella terrigena) treatments positively affected dry weight and physiological parameters searched in both species. Statistically significant differences were observed between bacterial inoculation and B fertilizer on root and shoot dry weight under non-cold-stress (NCS) and cold-stress (CS) conditions. Leaf total chlorophyll content (LTCC), stomatal conductance (SC), leaf relative water content (LRWC), and membrane leakage (ML) were negatively affected by CS conditions and decreased with reduced temperatures of media, but B and PGPR application alleviate the low-temperature deleterious effect in both species. The greatest SC and LRWC, and the lowest ML, were obtained by 6 kg B ha−1 combined with R. terrigena treatment. The greatest LTCC in both NCS and CS conditions was observed with B. megaterium M3 application alone.

Isolation of 3 Flavonoids from Mentha longifolia (L.) Hudson subsp. longifolia and Determination of Their Genotoxic Potentials by Using the E. coli WP2 Test System

UNLABELLED Flavonoids, abundant in most of plant species, are widely used in medicine and development studies on phytotherapeutic drugs due to their various biological activities. In the present study, 3 flavonoids, apigenin-7-O-glucoside, apigenin-7-O-rutinoside, and apigenin-7-O-glucuronide, were isolated from Mentha longifolia (L.) Hudson subsp. longifolia by using E. coli WP2 genotoxicity assay guided fractionation procedures. Later, the mutagenic and antimutagenic properties of each flavonoid were evaluated by using the same genotoxicity assay. The results showed that all the test compounds have significant antimutagenic activity at tested concentrations with or without S9 activation. The inhibition rates were between 25.3% (apigenin-7-O-glucoside with S9-2.0 μM/plate) and 59.0% (apigenin-7-O-rutinoside without S9-2.0 μM/plate). In conclusion, the results revealed that the 3 flavonoids from Mentha longifolia (L.) Hudson subsp. longifolia have significant antimutagenic activity, and the findings of the present study are valuable for further investigations, focus on the phytotherapeutic drug discovery. PRACTICAL APPLICATION Apigenin derivatives can be thought as genetically safe at tested concentrations because they did not show mutagenic activity. Furthermore, they have also significant antimutagenic activity. These are valuable for further research focus on phytotherapeutic drug discovery and development.

The synthesis, characterization, antimicrobial and antimutagenic activities of hydroxyphenylimino ligands and their metal complexes of usnic acid isolated from Usnea longissima

Novel multifunctional hydroxyphenylimino ligands (L1, L2 and L3) were synthesized by the condensation of 2-aminophenol, 3-aminophenol and 4-aminophenol with usnic acid, a lichen metabolite. The synthesized ligands and their Cu(II), Co(II), Ni(II) and Mn(II) complexes were characterized using FT-IR, UV-Vis, (1)H-NMR, (13)C-NMR, 1D- and 2D NMR (DEPT, COSY, HMQC and HMBC), LC-MS and TGA. In addition, the metal complexes of the novel ligands were prepared with high yields using Cu(II), Co(II), Ni(II) and Mn(II) salts and were characterized using the FT-MIR/FAR, UV-Vis, elemental analysis, ICP-OES and TG/DTA techniques. The ligands and their complexes were tested against ten important pathogen microorganisms using the disc diffusion method and the metal complexes of the ligands were more active against all of the microorganisms tested with a broad spectrum than the ligands exhibiting 11–32 mm inhibition zones. On the other hand, a broad spectrum of the strongest antimicrobial activity was determined for the Mn(II) and Cu(II) complexes of the hydroxyphenylimino ligand with usnic acid (L3). In addition, the antimutagenic activities of all of the ligands and their metal complexes were determined using the Ames-Salmonella and E. coli WP2 microbial assay systems and they showed varied and strong antimutagenic effects. In general, it has been found that the Co and Mn complexes of the ligands possess potent antimutagenic activity. In view of these results, it can be concluded that some metal complexes can be used as antimicrobial and anticancer agents.