Evaluation of the chemopreventive effects of Hypericum perforatum L on DMBA-applied rat oral mucosa.

OBJECTIVE: Hypericum perforatum L also known as St. John's wort is known to have many beneficial properties for the organism including its antioxidant and anticancer activities. It is also known to have shown antiproliferative and cytotoxic effects against various cancer cell lines. The purpose of this study was to investigate the effects of Hypericum perforatum L on 7,12-dimethylbenz(a)anthracene-induced rat oral squamous cell carcinoma model. DESIGN: The in vitro antioxidant properties of Hypericum perforatum L was determined and an extract was prepared. Thirty Wistar male rats were divided randomly into 4 groups (Control group, DMBA group, HP + DMBA group, HP group). The antioxidant defense mechanisms in tissue and blood samples were evaluated biochemically and immunohistochemically, the carcinomatous changes in connective tissue were investigated immunohistochemically and epithelial changes in the tissue samples were evaluated histopathologically. RESULTS: The extract revealed inhibitory effects on some antioxidant enzymes (catalase, glutathione peroxidase). Immunohistochemical evaluations revealed no invasive changes in the connective tissue. Hypericum perforatum L demonstrated chemopreventive effects although it did not prevent carcinomatous changes altogether. CONCLUSIONS: Hypericum perforatum L is a promising chemopreventive agent and further studies are needed in order to evaluate the full potential of this plant.

Characterisation of Streptomyces violascens OC125-8 lipase for oily wastewater treatment.

In this study, the lipase-producing bacterium Streptomyces violascens (GenBank number MF621564) was identified, and the extracellular S. violascens OC125-8 lipase produced by this strain was characterised for use in wastewater treatment. The lipase was partially purified by ammonium sulphate precipitation at a final yield of 3.28-fold purification and a recovery of 56%. The S. violascens OC125-8 lipase exhibited optimum catalytic activity at 40 °C and pH 8.0; it was stable at 30-40 °C with more than 86% residual activity after 1 h; it was also stable over a relatively broad pH range of pH 7.0-11.0, retaining 83.3-100% activity. V max and K m values were calculated as 0.61 µmol/min/mg and 0.259 mM, respectively. Enzyme activity significantly increased in the presence of Fe2+ ion but was inhibited by Ca2+, Mn2+, Cu2+ and Mg2+. The addition of a serine protease inhibitor, phenylmethylsulfonyl fluoride (PMSF), strongly inhibited enzyme activity while ethylenediaminetetraacetic acid (EDTA), a metal chelating agent, had no inhibitory effect. The enzyme was fairly stable in the presence of surfactants as well as sodium perborate. Examination of commercial detergent tolerance revealed that the lipase was strongly stable in Tursil (88%), Pril (97%) and Fairy (98.5%), while the lipase was activated in Omo (113.4%) and Ariel (128.3%). Moreover, the lipase showed highest activity towards olive oil (100%), sunflower oil (90%) and burned sunflower oil (55%), while corn oil (44%) and burned olive oil (15%) were less hydrolysed by the enzyme. These properties demonstrate that S. violascens OC125-8 lipase is an ideal choice for oily wastewater management.

The Effects of Hypericum perforatum L. on the Proliferation, Osteogenic Differentiation, and Inflammatory Response of Mesenchymal Stem Cells from Different Niches.

The aim of this study is to demonstrate and compare the differentiation, proliferation, migration and inflammatory behavior of dental pulp- and bone marrow-derived mesenchymal stem cells (DP-MSCs and BM-MSCs) in response to a Hypericum perforatum ethanol extract. Using xCELLigence, a real-time monitoring system, a dose of 10 µg/mL was found to be the most efficient concentration for vitality. The IC50 values and doubling time were calculated. The results showed that H. perforatum L. was able to accelerate osteogenic differentiation in DP-MSCs, but calcium granulation was impaired in BM-MSCs. H. perforatum L.-induced migration increased when compared to the TNF-α-induced migration in a Transwell migration assay, and the IL-6 cytokine levels between cells also differed. It can be suggested that tissue memory is an important factor in MSCs, and that they differ in their response to external factors. In conclusion, H. perforatum L. can be considered an excellent osteoinductive agent for DP-MSCs but should not be used for BM-MSCs. Tissue-specific osteoinductive agents should be discussed in future studies.

Effects of Syzygium aromaticum, Cinnamomum zeylanicum, and Salvia triloba extracts on proliferation and differentiation of dental pulp stem cells.

INTRODUCTION: Hypersensitivity, local irritative and cytotoxic effects are known for the chemical components of Syzygium aromaticum and Cinnamomum zeylanicum contained in dental materials. However, there is no intimate data in dentistry using the whole extracts of these plants and introducing new ones. Salvia triloba is a well-known anti-inflammatory plant that correspondingly could be used in several dental traumas. OBJECTIVES: We aimed to show and compare the effect of S. aromaticum, C. zeylanicum, and S. triloba extracts on dental pulp stem cells (DPSCs) proliferation, differentiation, and immune responses. MATERIAL AND METHODS: Using xCELLigence, a real time monitoring system, we obtained a growth curve of DPSCs with different concentrations of the Extracts. A dose of 10 µg/mL was the most efficient concentration for vitality. Osteogenic differentiation and anti-inflammatory activities were determined by using an ELISA Kit to detect early and late markers of differentiation. RESULTS: The level of osteonectin (ON, early osteogenic marker) decreased, which indicated that the osteogenic differentiation may be accelerated with addition of extracts. However, the level of osteocalcin (OCN, late osteogenic marker and sign of calcium granulation) differed among the extracts, in which S. aromaticum presented the highest value, followed by S. triloba and C. zeylanicum. Surprisingly, the determined calcium granules were reduced in S. aromaticum and S. triloba. In response to tumor necrosis factor alpha (TNF-α), S. triloba-treated DPSCs showed the most reduced level of IL-6 cytokine level. We suggest C. zeylanicum as a promising osteogenic inducer and S. triloba as a potent anti-inflammatory agent, which could be used safely in biocomposite or scaffold fabrications for dentistry. CONCLUSIONS: Because calcium granule formation and cell viability play a critical role in hard tissue formation, S. aromaticum in dentistry should be strictly controlled, and the mechanism leading to reduced calcium granule formation should be identified.

The mutagenic, antimutagenic and antioxidant properties of Hypericum lydium.

CONTEXT: There is a growing market demand for Hypericum sp., a pharmacologically active plant that has been traditionally used to treat various ailments. However, there have been limited studies on the extract or essential oil of Hypericum lydium Boiss (Hypericaceae). OBJECTIVE: This study investigates for the first time the antioxidant, mutagenic and antimutagenic activity of an ethanol extract of H. lydium. MATERIAL AND METHODS: Ethanol extract from aerial parts of H. lydium harvested from Turkey were tested for this mutagenic and antimutagenic activities (2.0-0.002 mg/plate) using Ames Salmonella/microsome test system. 4-Nitro-o-phenylenediamine (4-NPD) (3 µg/plate) for the Salmonella typhimurium TA98 and sodium azide (NaN3) (8 µg/plate) for the S. typhimurium TA100 were used as positive controls. The antioxidant activity, total antioxidant activity and phenolic constituent of the extract (2.0-0.002 mg/mL) was determined by the inhibition of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ß-carotene-linoleic acid model and by means of Folin-Ciocalteu reagent, respectively. RESULTS: The extract showed no sign of mutagenicity at the tested concentrations (0.002-2.0 mg/mL), and showed concentration-dependent antimutagenic activity against NaN3 and 4-NPD ranging from 26.8 to 81.5%. The extract was found to be an efficient scavenger of DPPH (IC50 0.165 ± 0.23 mg/mL) and to inhibit ß-carotene-linoleic acid bleaching (IC50 0.39 ± 0.11 mg/mL). DISCUSSION AND CONCLUSION: These findings indicate ethanol extract of H. lydium to be a safe and effective agent that may be incorporated into new strategies for the prevention of cancer and mutagenesis.

The antioxidant and antimutagenic activities of Ankaferd blood stopper,a natural hemostatic agent used in dentistry.

BACKGROUND/AIM: This study investigated the antioxidant and antimutagenic properties of Ankaferd blood stopper (ABS), a plant-based topical hemostatic agent used in Turkey to treat external hemorrhages and bleeding during dental surgery. While previous studies have examined the antimicrobial, antiinflammatory, and anticarcinogenic properties of ABS, to our knowledge, this is the first study to report on the antioxidant and antimutagenic activities of this drug. MATERIALS AND METHODS: Antioxidant activity was evaluated using DPPH radical-scavenging and ß-carotene-linoleic acid tests. Antimutagenic activity was assessed using the Ames Salmonella/microsome mutagenicity test with the bacterial mutant strains Salmonella typhimurium TA98 and TA100. RESULTS: Although ABS demonstrated no free-radical-scavenging activity in DPPH assays at the tested concentrations, ß-carotene-linoleic acid testing found ABS to have a total antioxidant activity rate of 47.06 ± 4.41%. Antimutagenic effects were observed on TA100 at plate concentrations of 5%, 0.5%, and 0.05%, and on TA98 only at a plate concentration of 5%. CONCLUSION: ABS was shown to possess antioxidant and antimutagenic properties that could be of potential value in the fields of medicine and dentistry.

Evaluation of fruit extracts of six Turkish Juniperus species for their antioxidant, anticholinesterase and antimicrobial activities.

BACKGROUND: Juniperus L. (Cupressaceae) species are mostly spread out in the Northern Hemisphere of the world, and some of them are used as folkloric medicines. The fruits of some species are eaten. Since oxidative stress is one of the reasons for neurodegeneration and is associated with the Alzheimer's disease (AD), the extracts prepared from the fruits of six Juniperus species were screened for their antioxidant activity. Therefore, the extracts were also evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), which are chief enzymes in the pathogenesis of AD. In addition, antimicrobial activity was also evaluated. RESULTS: In the ß-carotene-linoleic acid assay, acetone extracts of J. oxycedrus subsp. oxycedrus, J. sabina and J. excelsa, and methanol extracts of J. phoenicea and J. sabina, effectively inhibited oxidation of linoleic acid. The hexane extracts of J. oxycedrus subsp. oxycedrus, J. foetidissima and J. phoenicea showed remarkable inhibitory effect against AChE and BChE. CONCLUSION: Because of their high antioxidant activity, J. excelsa, J. oxycedrus subsp. oxycedrus, J. sabina and J. phoenicia might be used in the food industry as preservative agents or extension of the shelf-life of raw and processed foods. Since the hexane extracts of J. oxycedrus subsp. oxycedrus and J. foetidissima demonstrated significant anticholinesterase activity they should be considered as a potential source for anticholinesterase agents.

Antimicrobial activity and chemical composition of endemic Centaurea cariensis subsp. niveo-tomentosa.

The antimicrobial activity of the n-hexane, chloroform, ethyl acetate and ethyl alcohol extracts of the aerial parts of Centaurea cariensis subsp. niveo-tomentosa was evaluated against microorganisms, including multi-antibiotic resistant bacteria, using the paper disc diffusion method. The chemical composition of the chloroform extract of this plant was determined by gas chromatography and gas chromatography-mass spectrometry. The chloroform extract exhibited significant antibacterial activity for all bacteria tested, which are important pathogens. The major compounds of the chloroform extract were caryophyllene oxide (20.79%), spathulenol (14.73%), beta-eudesmol (9.27%), beta-caryophyllene (6.84%), n-cetylalcohol (6.27%), cubenol (5.23%) and cis-alpha-santalol (4.67%), respectively.

Chemical composition of endemic Scorzonera sandrasica and studies on the antimicrobial activity against multiresistant bacteria.

The present study describes the antimicrobial activity and chemical composition of Scorzonera sandrasica Hartvig et Strid (Family Asteraceae), endemic to Turkey. The antimicrobial activity of the hexane, chloroform, ethyl acetate, and ethanol extracts of the aerial parts of S. sandrasica was evaluated against microorganisms, including multiresistant bacteria, using a paper disc diffusion method. The chemical composition of the chloroform extract of the plant was determined by gas chromatography and gas chromatography-mass spectrometry. The major compounds of the chloroform extract of the plant were caryophyllene oxide (19.7%), manoyl oxide (16.5%), and manool (11.3%), respectively. The extracts had antibacterial activity; however, no antifungal activity was observed against the two fungi. In particular, the ethanol and chloroform extracts exhibited significant activity against multiresistant strains of Stenotrophomonas maltophilia.

Chemical composition of endemic Centaurea austro-anatolica and studies of its antimicrobial activity against multi-resistant bacteria.

Hexane, chloroform, ethyl acetate and ethanolic extracts of the aerial parts of Centaurea austro-anatolica Hub.-Mor. (Asteraceae) were evaluated against microorganisms, including multiresistant bacteria, using a paper disc diffusion method. The chloroform extract exhibited significant antibacterial activity toward all bacteria tested. The chemical composition of the chloroform extract was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major compounds of the extract were caryophyllene oxide (21.32 %), spathulenol (10.86 %), n-tricosanol (9.58 %) and geranyl isovalerate (8.71 %).

In vitro study of antibacterial activity on multi-resistant bacteria and chemical composition of the chloroform extract of endemic Centaurea drabifolia subsp. cappadocica.

The antimicrobial activity of the n-hexane, chloroform, ethyl acetate and ethanol extracts of the aerial parts of C. drabifolia S.M. subsp. cappadocica (DC.) Wagenitz (Asteraceae) was evaluated against microorganisms including multi-antibiotic resistant bacteria using the paper disc diffusion method. The chemical composition of the chloroform extract of this plant was determined by gas chromatography and gas chromatography-mass spectrometry. The chloroform extract exhibited significant antibacterial activity against all the bacteria tested, except Stenotrophomonas maltophilia MU63. The major compounds of the chloroform extract were spathulenol (14.1%), caryophyllene oxide (12.5%), octadecanol (10.2%), ethyl palmitate (7.7%), [Z,Z]-10,12-hexadecadienal (6.0%), 3-hydroxy p-anisaldehyde (5.9%) and pentacosane (5.8%).

The in vitro antimicrobial activities of the essential oils of some Lamiaceae species from Turkey.

In this study, antimicrobial activities of the essential oils obtained by using the hydrodistillation method from some lamiaceous plants--Mentha longifolia (L.) Hudson ssp. longifolia, M. longifolia (L.) Hudson ssp. typhoides (Briq.) Harley var. typhoides, Mentha pulegium L., Salvia fruticosa Miller, Salvia tomentosa Miller, Calamintha nepeta (L.) Savi ssp. glandulosa (Req.) P.W. Ball, Nepeta cadmea Boiss., Lavandula stoechas L. ssp. stoechas, and Ziziphora tenuior L.--were determined by using the disc diffusion method. The plants used in this study were collected from different localities of Mugla Province, Turkey. All the essential oils isolated from the plants were very effective against Gram-positive and Gram-negative bacteria, which included multiple-antibiotic resistant strains, except Pseudomonas aeruginosa ATCC 27853 and Pseudomonas fluorescens MU 87. The essential oils of the plant species, except S. tomentosa and S. fruticosa, were very effective against Candida albicans. The antimicrobial activities varied depending on the species, subspecies, or variety. In fact, essential oils of some plants belonging to the same taxa but collected from different localities showed different levels of antimicrobial activities.

Antimicrobial activity and chemical composition of Senecio sandrasicus on antibiotic resistant staphylococci.

The antimicrobial activity of hexane, chloroform, ethyl acetate and ethanol extracts of the aerial parts of S. sandrasicus P.H.Davis (Asteraceae), endemic to Sandras mountain (Turkey), were determined. The antimicrobial activity of the extracts on microorganisms including multi-resistant staphylococci were evaluated using the disc diffusion method. The strains of multi-resistant staphylococci and the other standart bacteria were inhibited by some extracts. The volatile organic compouds of S. sandrasicus was determined by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). The major compounds of hexane extract were aromadendrene oxide 2 (13.3%), spathulenol (12.5%) and beta-caryophylene (11.8%), respectively.

Chemical composition, antimicrobial and antioxidant activities of Centaurea ensiformis Hub.-Mor. (Asteraceae), a species endemic to Mugla (Turkey).

The n-hexane, chloroform, ethyl acetate and ethyl alcohol extracts of the aerial parts of Centaurea ensiformis, endemic to Turkey, have been assessed for antimicrobial and antioxidant activities. The chemical composition of the hexane extract of this plant was determined. The antimicrobial activities on microorganisms, including multiple antibiotic resistant bacteria, were evaluated using the disc diffusion method. The antioxidant activities were determined by using four complementary in vitro assays: inhibition of 2,2-diphenyl-1-picrylhydrazyl radical, total antioxidant activity, and the total amount of phenolic and flavonoid compounds. The structure of the active extract was elucidated by: thin layer chromatography, column chromatography, gas chromatography or gas chromatography-mass spectrometry. The various extracts of C. ensiformis inhibited the growth of tested bacteria. All the C. ensiformis extracts had no effect on the yeasts. The total antioxidant activity increased with the increasing amount of the extracts (20, 40, 80 and 160 microg), which contained linoleic acid emulsion. The major compounds of the hexane extract of the plant were caryophyllene oxide (28.72%), spathulenol (17.81%), eudesmol (13.03%) and beta-bourbonene (8.51%).

Antimicrobial activities of the essential oils of Origanum onites L., Origanum vulgare L. subspecies hirtum (Link) Ietswaart, Satureja thymbra L., and Thymus cilicicus Boiss. & Bal. growing wild in Turkey.

In the present study, four separate samples of Origanum onites L., three separate samples of Satureja thymbra L., Origanum vulgare L. ssp. hirtum (Link) Ietswaart, and Thymus cilicicus Boiss. & Bal. were collected from various regions of Mugla, Turkey. The essential oils of these plants were obtained by the hydrodistillation method. Antimicrobial activities of the essential oils against microorganisms, including multiple antibiotic-resistant bacteria, were investigated using the disc diffusion method. Different antibiotic discs were used for comparison to the inhibition zones. All the essential oils used in this study were very effective against Gram-positive and Gram-negative bacteria, which included multiple resistant strains, except Pseudomonas aeruginosa ATCC 27853 and Pseudomonas fluorescens MU 87. The essential oils of the O. onites, O. vulgare ssp. hirtum, and S. thymbra were especially very effective against the resistant strains such as Stenotrophomonas maltophilia MU 64, S. maltophilia MU 99, and Chryseomonas luteola MU 65. The maximum antimicrobial activity was observed with the essential oils of O. onites. The antimicrobial activities of the essential oils varied depending on the species, subspecies, or variety. In fact, the essential oils of some plants belonging to the same species that were collected from different locations showed different levels of antimicrobial activities.

Inhibition of quorum sensing-regulated behaviors by Scorzonera sandrasica.

Many Gram-negative bacteria use N-acyl homoserine lactone signal molecules to monitor their own population density and coordinate gene regulation in a process called quorum sensing (QS). Increasing evidence implies that certain eukaryotes produce QS-inhibitory compounds. In this work, we tested 46 terrestrial plants materials for their ability to inhibit QS-regulated behaviors in different bacterial species. Plant materials were dried and extracted using different solvents. The chloroform-soluble compounds extracted from Scorzonera sandrasica were found to inhibit violacein production, a QS-regulated behavior in Chromobacterium violaceum. In addition, the chloroform extract was also able to inhibit QS-regulated carbapenem antibiotic production in Erwinia carotovora. Because the regulation of many bacterial processes is controlled by QS systems, the finding of natural compounds acting as QS inhibitors suggests an attractive tool to control and handle detrimental infections caused by human, animal, and plant pathogens.

The constituents of essential oil and in vitro antimicrobial activity of Micromeria cilicica from Turkey.

The chemical composition of the essential oil of Micromeria cilicica (Labiatae) that has been used in folk medicine were analysed by GC, GC-MS, 1H NMR and 13C NMR. The totals of 34 components in hydrodistillation, 30 components in steam distillation were detected. The major component characterized in the essential oils was pulegone (66.55, 64.10%) and other main components were determined as cis-p-menthone (21.71, 25.31%), trans-p-menthone (9.59, 5.59%), nerol (0.35, 2.49%) and 3-octonol (0.81, 0.25%), respectively. Essential oils obtained by hydro and steam distillation and organic solvent extracts of the aerial parts of the plant were investigated for antimicrobial activities on several microorganisms including bacteria and yeast. Moreover, the main constituent of the oil has been tested against the same microorganisms. The extracts and pulegone exhibited a significant antibacterial and antifungal activity. The activities were increased depend on the amount of extracts and pulegone. Pulegone also showed antimicrobial activity, particularly against Candida albicans and Salmonella typhimurium. Furthermore Candida albicans is the most susceptible to pulegone giving two times the effect of nystatin.

An in vitro study on antimicrobial activity of propolis from Mugla province of Turkey.

Antibacterial and antifungal activities of acetone and dimethyl sulfoxide (DMSO) extracts of 45 different propolis samples from the Mugla province of Turkey were investigated. Antimicrobial activity of propolis varied depending on propolis sample, dosage of propolis, and the extraction solvents for all test microorganisms. Antimicrobial activity of all propolis samples increased with increasing dosage without reaching a plateau at the highest dosage tested. Except for Brucella melitensis, the DMSO extracts of all propolis samples were more active than the acetone extracts of the same samples. For B. melitensis, the acetone extracts of all propolis samples showed greater activity. The most sensitive microorganism to propolis was Shigella sonnei in the gram-negative group and Streptococcus mutans in the gram-positive group. The least sensitive microorganism was Candida albicans. A control test run with standard antibiotics revealed that propolis samples from the Mugla province of Turkey has a similar or greater inhibitory effect on S. mutans, Salmonella typhi, Pseudomonas aeruginosa, S. sonnei, and C. albicans growth.