Biological Activities of the Fruit Essential Oil, Fruit, and Root Extracts of Ferula drudeana Korovin, the Putative Anatolian Ecotype of the Silphion Plant.

In the present study, preliminary phytochemical investigations were performed on the fruit essential oil and antioxidant-rich methanolic extracts of the fruits and roots of Ferula drudeana, the putative Anatolian ecotype of the Silphion plant, to corroborate its medicinal plant potential and identify its unique characteristics amongst other Ferula species. The essential oil from the fruits of the endemic species Ferula drudeana collected from Aksaray was analyzed by GC and GC/MS. The main components of the oil were determined as shyobunone (44.2%) and 6-epishyobunone (12.6%). The essential oil of the fruits and various solvent extracts of the fruits and roots of F. drudeana were evaluated for their antibacterial and anticandidal activity using microbroth dilution methods. The essential oil of the fruits, methanol, and methylene chloride extracts of the fruits and roots showed weak to moderate inhibitory activity against all tested microorganisms with MIC values of 78-2000 µg/mL. However, the petroleum ether extract of the roots showed remarkable inhibitory activity against Candida krusei and Candida utilis with MIC values of 19.5 and 9.75 µg/mL, respectively. Furthermore, all the samples were tested for their antioxidant activities using DPPH• TLC spot testing, online HPLC-ABTS screening, and DPPH/ABTS radical scavenging activity assessment assays. Methanolic extracts of the fruits and roots showed strong antioxidant activity in both systems.

Comparative Studies on Essential Oil and Phenolic Content with In Vitro Antioxidant, Anticholinesterase, Antimicrobial Activities of Achillea biebersteinii Afan. and A. millefolium subsp. millefolium Afan. L. Growing in Eastern Turkey.

The potential applications of Achillea species in various industries have encouraged the examination of their phytochemical components along with their biological potential. In the present study, phenolic contents and essential oil compositions together with the in vitro biological activities of the aerial parts from Achillea biebersteinii Afan. and Achillea millefolium subsp. millefolium Afan. collected from Turkey were evaluated. Different solvent extracts (n-hexane, chloroform, methanol, water) were prepared and their antimicrobial, anticholinesterase, and antioxidant activities were studied. The LC-MS/MS results revealed the presence of 16 different phenolic compounds, including chlorogenic acid, rutin, quercetin, and luteolin glycosides, in methanolic extracts. According to GC-FID and GC/MS results, the primary components of the oils were identified as 1,8-cineole (32.5%), piperitone (14.4%), and camphor (13.7%) in A. biebersteinii and 1,8-cineole (12.3%) and ß-eudesmol (8.9%) in A. millefolium subsp. millefolium. The infusion and methanolic extracts of both species were found to be rich in their total phenolic content as well as their antioxidant and anticholinesterase activity. In contrast, the n-hexane and chloroform extracts of both species showed strong antimicrobial activity with MIC values ranging from 15 to 2000 µg/mL. Our findings suggest that the investigated Achillea species could be evaluated as potent natural agents, and further studies into the promising extracts are needed.

Phytochemical composition and pharmacological activities of Teucrium polium L. collected from eastern Turkey.

Teucrium species that belong to the family Lamiaceae have been traditionally used for their medicinal properties. T. polium is one the most widespread members of the genus for its use in the treatment of several diseases. In this study, the essential oil and phenolic composition of the aerial parts from T. polium were assessed by GC-FID, GC/MS, and LC-MS/MS as well as for its total phenolic content. Several extracts such as n-hexane, chloroform, methanol, and infusion were prepared and their antimicrobial, antioxidant, and also acetylcholinesterase activities were studied. According to GC/MS results, ß -caryophyllene (8.8%), t-cadinol (6.2%), (E)-nerolidol (5%), α -cadinol (5.4%), and α-pinene (4.7%) were identified as main constituents of the essential oil. LC MS/MS analysis of the infusion and the methanol extract showed the presence of 15 phenolic compounds. Moreover, the total phenolic content of each sample was also determined and the infusion had the highest percentage of phenolics. To evaluate the antioxidant properties, the samples were tested by using DPPH" free radical scavenging, FRAP, and CUPRAC activity methods. The infusion showed the strongest radical scavenging activity, whereas n-hexane and chloroform extracts exhibited considerable reducing power effects. The MIC values for all of the examined microorganisms ranged from 15 to 2000 µg/mL with respect to antimicrobial activities.

Antibacterial, anticandidal and antioxidant properties of Tanacetum argenteum (Lam.) Willd. subsp. flabellifolium (Boiss. & Heldr.) Grierson.

In the present study hydrodistilled essential oil and total methanol extracts of Tanacetum argenteum subsp. flabellifolium have been evaluated for their antimicrobial and antioxidant effects. The chemical composition of the oil and the crude extract were determined by GC/FID, GC/MS and LC/DAD/ESI-MS systems respectively. ß-thujone (47.1%), α-pinene (19.1%) and α-thujone (10.5%) were the main compounds of the essential oil while the 5-Ocaffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, 4,5-O-dicaffeoylquinic acid were identified as flavonoid content of the crude extract. The oil and the methanol extract were demonstrated moderate antimicrobial effects (MIC range; 0,062-2,0 mg/mL) against 21 different pathogenic micro organism. Total phenolic content was determined as 63 mg GAE in g extract and the DPPH radical scavenging effect was determined as 0.16 mg/mL (IC50) and TEAC was determined as 0.21mMol.

Antibacterial profiling of abietane-type diterpenoids.

Abietic and dehydroabietic acid are interesting diterpenes with a highly diverse repertoire of associated bioactivities. They have, among others, shown antibacterial and antifungal activity, potentially valuable in the struggle against the increasing antimicrobial resistance and imminent antibiotic shortage. In this paper, we describe the synthesis of a set of 9 abietic and dehydroabietic acid derivatives containing amino acid side chains and their in vitro antimicrobial profiling against a panel of human pathogenic microbial strains. Furthermore, their in vitro cytotoxicity against mammalian cells was evaluated. The experimental results showed that the most promising compound was 10 [methyl N-(abiet-8,11,13-trien-18-yl)-d-serinate], with an MIC90 of 60µg/mL against Staphylococcus aureus ATCC 25923, and 8µg/mL against methicillin-resistant S. aureus, Staphylococcus epidermidis and Streptococcus mitis. The IC50 value for compound 10 against Balb/c 3T3 cells was 45µg/mL.

Chemical Composition and Biological Activity of Centaurea baseri: New Species from Turkey.

The genus Centaurea L. is one of the largest and important genera of Asteraceae family. Centaurea species have been widely used as herbal remedies in folk medicine for their antidandruff, antidiarrheic, antirheumatic, anti-inflammatory, choleretic, diuretic, digestive, stomachic, astringent, antipyretic, cytotoxic, and antibacterial properties. Centaurea baseri Kose & Alan is a recently described local endemic species in Turkey and this is the first study on the chemical composition and bioactivity of its hydrodistilled essential oil and the crude extract. According to chromatospectral analysis, hexadecanoic acid (42.3%), nonacosane (8.2%), and heptacosane (8.0%) were the main compounds of the essential oil, while 16 compounds were determined in the MeOH extract using LC/MS. Furthermore, antimicrobial, antioxidant, and cytotoxic effects of the essential oil and the extract were evaluated in comparison with the standard agents. The extract showed strong antifungal effect against Candida utilis at the concentration of 60 µg/ml (MIC) where the EO showed growth inhibition at the concentration of 47.00 µg/ml (MIC) against pathogen Bacillus cereus. Both the essential oil and the extract did not show any selective antioxidant properties. The extract showed remarkably selective cytotoxic properties against MCF-7, PANC-1, A549, and C6 glioma cells.

Anticandidal Effects of Thymoquinone: Mode of Action Determined by Transmission Electron Microscopy (TEM).

Thymoquin6ne (TQ) is one of the bioactive constituents of black cumin seed (Nigella sativa L.) oil. It is well known that this natural volatile quinone has remarkable antimicrobial effects, especially against Candida species. Consequently, in this present study TQ was evaluated for its anticandidal effects against. 14 differet.pathogenic Candida strains by using the in vitro, partly modified, microdilution CLSI M27-A2 method. After TQ treatment at the minimum inhibitory concentration (MIC), ultra-thin sections of C. albicans cells were thoroughly evaluated by transmission electron microscopy (TEM). The mode of action of TQ on different Candida cells was elaborated, where their disintegration and disorganization with amorphous nucleus were observed microscopically.

Synthesis, anticandidal activity and cytotoxicity of some tetrazole derivatives.

In this study, 14 different 2-[(1-methyl-1H-tetrazole-5-yl)thio]-1-(phenyl)ethanone derivatives (1-14) were synthesized. The structures of the obtained compounds were elucidated using IR, (1)H-NMR, (13)C-NMR and FAB(+)-MS spectral data and elemental analyses results. The compounds were screened for their anticandidal activity using the microbroth dilution method and for their cytotoxic effects using the MTT assay against NIH/3T3 cells. Some of the compounds were found to be potent anticandidal agents with weak cytotoxicities.

Synthesis and biological evaluation of some hydrazone derivatives as new anticandidal and anticancer agents.

New hydrazone derivatives were synthesized via the nucleophilic addition-elimination reaction of 2-[(1-methyl-1H-tetrazol-5-yl)thio)]acetohydrazide with aromatic aldehydes/ketones. The compounds were tested in vitro against various Candida species and compared with ketoconazole. Genotoxicity of the most effective anticandidal compounds was evaluated by umuC and Ames assays. All compounds were also investigated for their cytotoxic effects on NIH3T3 and A549 cell lines. Compound 8 was the most effective antifungal derivative against C. albicans (ATCC-90028) with a MIC value of 0.05 mg/mL. Compound 5 can be identified as the most promising anticancer agent against A549 cancer cell lines due to its inhibitory effect on A549 cell lines and low toxicity to NIH3T3 cells.

Antimicrobial and antioxidant activities of Stachys lavandulifolia subsp. lavandulifolia essential oil and its infusion.

Stachys lavandulifolia Vahl. subsp. lavandulifolia (Lamiaceae) is widely used in south Anatolia as a herbal tea. It is used for the treatment of gastrointestinal and respiratory disorders. Constituents of the essential oil obtained by hydrodistillation were analyzed both by GC-FID and GC/MS, simultaneously. Thirty-seven compounds representing 98.3% of the oil were characterized. Beta-Phellandrene (27%), alpha-pinene (18.5%) and germacrene-D (13%) were found as major components of the oil. Anticandidal, antibacterial and antioxidant properties of the oil and the prepared infusion were evaluated using several methods. The oil exhibited good inhibitory activity on Candida tropicalis (MIC 0.094 mg/mL). Staphylococcus aureus and Salmonella typhimurium growths were also inhibited by the oil at a concentration of 0.375 mg/mL. The prepared infusion of the flowering aerial parts showed weak antimicrobial effects against all the tested microorganisms, but demonstrated a remarkably radical scavenging activity (IC50: 3.9 microg/mL).

Biotransformation of (-)-(R)-α-phellandrene: antimicrobial activity of its major metabolite.

Terpene derivatives converted by microbial biotransformation constitute an important resource for natural pharmaceutical, fragrance, and aroma substances. In the present study, the monoterpene α-phellandrene was biotransformed by 16 different strains of microorganisms (bacteria, fungi, and yeasts). The transformation metabolites were initially screened by TLC and GC/MS, and then further characterized by NMR spectroscopic techniques. Among the six metabolites characterized, 6-hydroxypiperitone, α-phellandrene epoxide, cis-p-menth-2-en-1-ol, and carvotanacetone, which originated from (-)-(R)-α-phellandrene, are reported for the first time in this study. Additionally, the substrate and the metabolite 5-p-menthene-1,2-diol were subjected to in vitro antibacterial and anticandidal tests. The metabolite showed moderate-to-good inhibitory activities (MICs=0.125 to >4 mg/ml) against various bacteria and especially against Candida species in comparison with its substrate (-)-(R)-α-phellandrene and standard antimicrobial agents.

Anticandidal activity of the essential oil of Nepeta transcaucasica Grossh.

Hydrodistallation of the aerial parts of Nepeta transcaucasica Grossh. (Lamiaceae), collected in Agri, Dogubayazit Province, afforded an essential oil that was characterized by GC and GC/MS analyses. Twenty-seven compounds, representing 97.69% of the total oil composition, were identified, and 4aα,7α,7aß-nepetalactone (1; 39%), 4aα,7α,7aα-nepetalactone (2; 28%), and germacrene D (3; 15%) constituted the major components. The anticandidal effects of the oil were evaluated against seven Candida strains by using the broth microdilution method. The oil showed good inhibitory effects against C. glabrata and C. tropicalis at minimal inhibitory concentrations (MICs) of 0.09 and 0.375 mg/ml, respectively.

Synthesis and anticandidal activity of new triazolothiadiazine derivatives.

New triazolothiadiazine derivatives were synthesized via the ring closure reaction of 4-amino-5-substituted-2,4-dihydro-3H-1,2,4-triazol-3-thiones with phenacyl bromides. The compounds were tested in vitro against various Candida species and compared with ketoconazole. Among these compounds, the compound bearing cyclohexyl moiety and p-chlorophenyl substituent on triazolothiadiazine ring (2i) was found to be the most potent derivative against Candida albicans (ATCC 90028). It is clear that there is a positive correlation between anticandidal activity and two functional moieties, namely cycloaliphatic group and p-chlorophenyl substituent on triazolothiadiazine ring. The compounds were also investigated for their cytotoxic effects using MTT assay. Compound 2a exhibited the highest cytotoxic activity, whereas compound 2f possessed the lowest cytotoxic activity against NIH/3T3 cells.

Preparation of some pyrazoline derivatives and evaluation of their antifungal activities.

The synthesis of a new series of 1-[(benzazole-2-yl)thioacetyl]-3,5-diaryl-2-pyrazoline derivatives was obtained by reacting 1-(chloroacetyl)-3,5-diaryl-pyrazolines with 2-mercaptobenzimidazole/benzoxazole/benzothiazole. The chemical structures of the compounds were elucidated by (1)H-NMR, (13)C-NMR, and FAB(+)-MS spectral data. Their antifungal activities against Candida albicans, Candida glabrata, Candida utilis, Candida tropicalis, Candida krusei, and Candida parapsilosis were investigated. A significant level of activity was observed.

Synthesis and the selective antifungal activity of 5,6,7,8-tetrahydroimidazo[1,2-a]pyridine derivatives.

Even though there are new classes of compounds now frequently used in treatment of fungal infections, the density of deeply invasive candidiasis has increased at least 10-fold during the past decade. Furthermore, many infections due to Candida species are actually refractory to antifungal therapy. In this present study, it was aimed to synthesize, new hydrazide derivatives of tetrahydroimidazo[1,2-a]pyridine and evaluate their anticandidal activity and cytotoxicity in vitro. The reaction of tetrahydroimidazo[1,2-a]pyridine-2-carboxylic acid hydrazides with various benzaldehydes gave tetrahydroimidazo[1,2-a]pyridine-2-carboxylic acid benzylidene hydrazide derivatives. The chemical structures of the compounds were elucidated and confirmed by IR, 1H NMR, MS-FAB+ spectroscopy and elemental analyses. Eight new tetrahydroimidazo[1,2-a]pyridine derivatives were synthesized and screened for their antifungal effects against a panel of ten human pathogenic Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, Candida tropicalis, Candida utilis, and Candida zeylanoides using agar diffusion and broth microdilution assays, respectively. Furthermore, their cytotoxicity was tested against six mammalian cell lines. Among the analogues, the compound 5,6,7,8-tetrahydroimidazo[1,2-a]pyridine-2-carboxylic acid-(4-cyanobenzylidene) showed very strong inhibitory activity (up to MIC 0.016 mg/mL) against the screened Candida species. The same compound showed no in vitro toxicity up to 25 microg/mL concentration suggesting that its antifungal activity (MICs 0.016-1 mg/mL) is selective.

Studies on hydrazone derivatives as antifungal agents.

The increasing clinical importance of drug-resistant fungal pathogens has urged additional need to fungal research and new antifungal compound development. For this purpose, some N-(1-benzyl-2-phenylethylidene)-N'-[4-(aryl)thiazol-2-yl]hydrazone (1a-e) and N-(1-phenylbutylidene)-N'-[4-(aryl)thiazol-2-yl]hydrazone (2a-e) derivatives were synthesised and evaluated for antifungal activity. Their antifungal activities against standard and clinical strands of Candida albicans, Candida glabrata, Candida utilis, Candida tropicalis, Candida krusei, Candida zeylanoides, and Candida parapsilosis were investigated. A significant level of activity was observed.

The essential oil constituents and antimicrobial activity of Anthemis aciphylla BOISS. var. discoidea BOISS.

The essential oil of aerial parts, leaves and flowers of the endemic Anthemis aciphylla BOISS. var. discoidea BOISS. (Asteraceae) were obtained by hydrodistillation. The oils were analyzed both by GC and GC-MS on a polar column. The monoterpenes alpha-pinene (9-49%) and terpinen-4-ol (22-32%) were characterized as the main constituents. An unknown component isolated from the essential oil was characterized by means of MS, HR-MS, FT-IR, 1D- and 2D-NMR techniques as isofaurinone (1). Furthermore, the biological activity of the essential oils was evaluated in various human pathogenic microorganisms using the broth microdilution method. Weak to moderate inhibitions (0.06-1.0 mg/ml) was observed.

Biological activity and composition of the essential oils of Achillea schischkinii Sosn. and Achillea aleppica DC. subsp. aleppica.

The essential oils obtained by water distillation from aerial parts of Achillea schischkinii Sosn. and Achillea aleppica DC. subsp. aleppica were analyzed by gas chromatography and gas chromatography/mass spectrometry. 1,8-Cineole (32.5 and 26.1%, respectively) was the main component in both oils. The oil of A. aleppica subsp. aleppica was also found to be rich in bisabolol and its derivates. When tested for their antimicrobial, antiinflammatory, and antinociceptive activities, the oil of A. aleppica subsp. aleppica showed significant antiinflammatory, antinociceptive, and moderate antimicrobial activities.

The bioactive essential oil of Heracleum sphondylium L. subsp. ternatum (Velen.) Brummitt.

The essential oil of Heracleum sphondylium L subsp. ternatun (Velen.) Brummit (Umbelliferae) was isolated from crushed seeds by means of hydrodistillation and analyzed by GC and GC/MS. Major components were identified as 1-octanol (50.3%), octyl butyrate (24.6%), and octyl acetate (7.3%). Furthermore, antimicrobial activity of the oil was evaluated using microdilution broth and agar diffusion methods. The bioactive constituent of the essential oil was determined as 1-octanol by using a bioautography assay.

Antimicrobial screening of Mentha piperita essential oils.

Essential oils of peppermint Mentha piperita L. (Lamiaceae), which are used in flavors, fragrances, and pharmaceuticals, were investigated for their antimicrobial properties against 21 human and plant pathogenic microorganisms. The bioactivity of the oils menthol and menthone was compared using the combination of in vitro techniques such as microdilution, agar diffusion, and bioautography. It was shown that all of the peppermint oils screened strongly inhibited plant pathogenic microorganisms, whereas human pathogens were only moderately inhibited. Chemical compositions of the oils were analyzed by GC and GC/MS. Using the bioautography assay, menthol was found to be responsible for the antimicrobial activity of these oils.