Gökçe Şeker Karatoprak

The Effect of Pelargonium endlicherianum Fenzl. root extracts on formation of nanoparticles and their antimicrobial activities

Herein, we report the biosynthesis of Ag NPs, for the first time, using identified antimicrobial molecules (gallic acid+apocynin) and (gallic acid+apocynin+quercetin) from the medicinal plant Pelargonium endlicherianum Fenzl. and dramatically enhanced antimicrobial activity. We also investigate the role of each molecule on formation Ag NPs and explain the increase in the antimicrobial activity of identified molecules mediated Ag NPs. The extraction protocols, 11% ethanol and 70% methanol, resulted in identification of different constituents of gallic acid+apocynin (M1) and gallic acid+apocynin+quercetin (M2) with respective concentrations. The M1-Ag and M2-Ag NPs exhibit excellent inhibitory activities towards Gram negative bacteria; Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Gram positive bacteria; Staphylococcus epidermidis ATCC 3699 bacterial using in vitro microdilution method. The minimum inhibitory concentration (MIC) values of M1-Ag and M2-Ag NPs were determined to be 7.81 and 6.25ppm for S. epidermidis, respectively. Surprisingly, MIC value for both Ag NPs was indicated to be identical as 9. 37ppm for P. aeruginosa and E., coli.

Phenolic Composition, Anti-inflammatory, Antioxidant and Antimicrobial Activities of Alchemilla mollis (Buser) Rothm

The current study was designed to evaluate the antioxidant, anti‐inflammatory and antimicrobial activities of Alchemilla mollis (Buser) Rothm. (Rosaceae) aerial parts extracts. Chemical composition was analyzed by spectrophotometric and chromatographic (HPLC) techniques. The antioxidant properties assessed included DPPH· and ABTS·+ radical scavenging, β‐carotene‐linoleic acid co‐oxidation assay. Antimicrobial activity was evaluated with disc diffusion and micro dilution method. In order to evaluate toxicity of the extracts, with the sulforhodamine B colorimetric assay L929 cell line (mouse fibroblast) was used. The anti‐inflammatory activities of the potent antioxidant extracts (methanol, 70% methanol, and water extracts) were determined by measuring the inhibitory effects on NO production and pro‐inflammatory cytokine TNF‐α levels in lipopolysaccharide stimulated RAW 264.7 cells. 70% methanol and water extracts which were found to be rich in phenolic compounds (184.79 and 172.60 mg GAE/g extract) showed higher antioxidant activity. Luteolin‐7‐O‐glucoside was the main compound in the extracts. Ethyl acetate and 70% methanol extracts showed higher antibacterial activity against Staphylococcus aureus and Salmonella enteritidis with MIC value of 125 μg/ml. 70% methanol extract potentially inhibited the NO and TNF‐α production (18.43 μm and 1556.22 pg/ml, respectively, 6 h).

Extracellular directed ag NPs formation and investigation of their antimicrobial and cytotoxic properties

The use of microbial cell culture a valuable tool for the biosynthesis of nanoparticles is considered a green technology as it is eco-friendly, inexpensive and simple. Here, the synthesis of nanosilver particle (AgNP) from the yeast, Saccharomyces cerevisiae, gram (+), Bacillus subtilis and gram (−), Escherichia coli was shown. In this field we are the first to study their the antimicrobial effects of the microorganisms mentioned above against pathogens and anticancer activity on MCF-7 cell line. Silver nanoparticles in the size range of 126–323 nm were synthesized extracellularly by the microorganisms, which have different cell structures. Optical absorption, scanning electron microscopy, and zetasizer analysis confirmed the silver nanoparticles formation. Antimicrobial activity of AgNPs was evaluated the minimum inhibition concentration and disc diffusion methods. AgNPs inhibited nearly 90% the growth of Gram-positive Listeria monocytogenes, Streptococcus pneumoniae and Gram-negative Haemophilus influenzae, Klebsiella pneumoniae, Neisseria meningitidis bacterial pathogens. Anticancer potentials of AgNPs were investigated by MTT method. The synthesized AgNPs exhibited excellent high toxicity on MCF-7 cells and had a dose-dependent effect on cell viability. Especially AgNP 2 eliminated 67% of the MCF-7 cells at the concentration of 3.125 μg/mL. We found that extracellular synthesis of nanoparticles from microbial culture may be ‘green’ alternative to physical and chemical methods from the point of view of synthesis in large amounts and easy process.

Chemical composition and biological investigation of Pelargonium endlicherianum root extracts

Abstract Context: Pelargonium endlicherianum Fenzl. (Geraniaceae) roots and flowers are traditionally used in Turkey as a decoction treatment against intestinal parasites. Neither the chemical composition nor the potential bioactivity of the plant roots has been studied before. Objectives: The phenolic content and effects of P. endlicherianum root extracts on antioxidant enzyme levels on A549 cells were studied for the first time. Materials and methods: The chemical composition was analyzed via spectrophotometric and chromatographic (HPLC MS/MS and HPLC) techniques. The antioxidant activity was determined at different concentrations ranging from 0.001 to 2 mg/mL using DPPH• and ABTS•+ radical scavenging activity, β-carotene-linoleic acid co-oxidation assay, protection of 2-deoxyribose and bovine brain-derived phospholipids against a hydroxyl radical-mediated degradation assay. Glutathione peroxidase and superoxide dismutase activities were also studied as well as the effects of the extracts on nitric oxide levels on IL-1β stimulated A549 cells. Results: The key parameters for the most active ethyl acetate extract included the following: DPPH• IC50: 0.23 mg/mL, TEAC/ABTS: 2.17 mmol/L Trolox, reduction: 0.41 mmol/g AsscE, and protection of lipid peroxidation IC50: 0.05 mg/mL. Furthermore, the ethyl acetate extract increased the SOD level significantly compared to control group (4.48 U/mL) at concentrations of 100 and 200 μg/mL SOD, 5.50 and 5.67 U/mL, respectively. Apocynin was identified as the major component, and the ethyl acetate fraction was found to be rich in phenolic compounds. Discussion and conclusion: Pelargonium endlicherianum root extracts displayed antioxidant activity and increased the antioxidant enzyme levels in IL-1β stimulated A549 cells, while decreasing the NO levels.

Phytochemical Profile and Biological Activities of Helianthemum canum l. baumg. from Turkey

In the current study, antioxidant, antibacterial activities, and the phenolic compositions of extracts from Helianthemum canum L. Baumg. (Apiaceae) aerial parts were investigated for the first time. The H. canum was extracted with 70% methanol (HCMeOH) and water (HCW). Both extracts were determined by total phenolic contents (3 mg/ml), flavonoids (1.5 mg/ml), flavonols (1.5 mg/ml), qualitative–quantitative compositions, iron (II) chelation activities (0.1 – 5 mg/ml), free radical scavenging activities (DPPH•: 0.01 – 0.6 mg/ml and ABTS+•: 0.125 – 0.5 mg/ml) and the effect upon inhibition of β‐carotene/linoleic acid co‐oxidation (1 mg/ml). The peroxidation level was also determined using the thiobarbituric acid method (0.01 – 1.5 mg/ml). The results of the activity tests given as IC50 values were estimated from non‐linear algorithm and compared with standards. Antibacterial activities of extracts and standards were evaluated against Gram‐negative and ‐positive ten standard strains using disc diffusion and broth microdilution methods. The MIC results (312.5 – 2500 μg/ml) against tested microorganisms varied from 625 to 2500 μg/ml. In HPLC analysis, 3,5‐dihydroxybenzoic acid was found as the main substance in both extracts. These results showed that HCMeOH was richer in phenolic compounds (284.13 ± 0.30 mg GAE/g extract) from HCW (244.55 ± 0.35 mg GAE/g extract). In conclusion, H. canum extracts showed in vitro antibacterial and antioxidant activities.