Antifungal and genotoxic effects of Thymus serpyllum as a root canal irrigant.

OBJECTIVES: The aim of this study was the assessment of the efficiency of the ethyl acetate (EthOAc) extract of Thymus serpyllum against Candida albicans and to compare it with sodium hypochlorite (NaOCl) and chlorhexidine (CHX), as well as their genotoxic effect. MATERIAL AND METHODS: The antifungal effectiveness of the EthOAc extract of Thymus serpyllum was determined using the agar disk diffusion method. The inhibition zones induced by the EthOAc extract were compared after 5 min, 60 min, and 24 h to those induced by standard solutions (2% CHX and 2% NaOCl). An in vitro genotoxicity assay was performed in cultured lymphocytes from the blood of human volunteers to observe micronuclei formation. Statistical analysis of the results was performed using the Kruskal-Wallis test and one-way analysis of variance. RESULTS: The inhibition zone of combination of CHX with EthOAc extract of Thymus serpyllum against C. albicans was 29.7 mm after 5 min, 28.3 mm after 60 min, and 29 mm after 24 h. The inhibition zone of NaOCl in combination with EthOAc extract of Thymus serpyllum against C. albicans was 0 mm. The EthOAc extract of Thymus serpyllum did not show a genotoxic effect on lymphocyte cells. CONCLUSIONS: The EthOAc extract of Thymus serpyllum in combination with CHX may be a useful root canal disinfection in endodontic therapy.

Antibacterial Effect of Matricaria chamomilla L. Extract Against Enterococcus faecalis.

Purpose: With the demand for better efficiency during endodontic therapy, the purpose of this in vitro study was to evaluate the efficiency of ethyl acetate (EthOAc) extract of Matricaria chamomilla (L.) against Enterococcus faecalis and compare with standard root canal irrigation solutions. Material and Methods: The antibacterial effect against Enterococcus faecalis of the EthOAc extract of Matricaria chamomilla was assessed without, or with dentine powder, using agar disk diffusion method. The inhibition zones induced by the EthOAc extract were observed after 5 minutes, 60 minutes, and 24 hours and compared with standard irrigation solutions (2% chlorhexidine and 2% sodium hypochlorite) without, or after mixing with dentine powder. Statistical analysis of the results were analysed with the Kruskal-Wallis test and one-way ANOVA. Results: There was no inhibition zone in samples with and without dentine powder after combination of ethyl acetate extract of Matricaria chamomilla with sodium hypochlorite. When the extract was used alone in samples without dentine powder, the inhibition zone was 9.7 mm after 24 h, but this zone was decreased after adding dentine powder (7.7 mm). When the extract was used in combination with CHX, the inhibition zone in samples with dentine powder was 25.3 mm, but it was decreased after adding dentine powder (21.7 mm). Conclusion: The EthOAc extract of Matricaria chamomilla as alternative root canal irrigant may be a useful natural agent with antibacterial activity against Enterococcus faecalis. Also, it showed promising results in endodontic therapy after combination with chlorhexidine in Enterococcus faecalis eradication.

Generation of flavor compounds by biotransformation of genetically modified hairy roots of Hypericum perforatum (L.) with basidiomycetes.

Altogether, 14 basidiomycetes (12BAD, 95PCH, 9WCOC, 5PSA, 96BCI, 331SHIBD, 4MSC, 74HFA, 220MPS, 115PFLA, 111 ICO C, 16LED, 6TSU, and 61LYP) were grown on solid and in liquid media using hairy roots of genetically modified Hypericum perforatum (L.) as the only source of carbon and nitrogen. After the first screening by GC-MS/MS-O, two fungi (115PFLA and 61LYP) which resulted in the most pleasant complex natural flavor by biotransformation were selected for further analysis. Twenty-four new volatile compounds were produced, from which 21 were identified (ethyl hexanoate, ethyl octanoate, benzaldehyde, 2-undecanone, (E,E)-2,4-decadienal, 1-octen-3-one, (E)-2-nonenal, ethyl nonanoate, 2-heptenal, 1-methoxy-4-methylbenzene, 3-octanone, 1-decen-3-one, (E)-2-octenal, 1-octen-3-ol, ß-linalool, ±trans-nerolidol, anisole, methyl benzoate, 2-pentylfuran, 1,3-dichloro-2-methoxybenzene, and 1-dodecanol). Thereof, 15 compounds were perceived at the ODP, from which 13 were identified. Compound identification was performed by comparison of Kovats indices (KI) and mass spectra to those of authentic reference compounds on a polar VF-WAXms column using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS).

Antifungal and Synergistic Effects of the Ethyl Acetate Extract of Tanacetum vulgare (L.) Against Candida albicans.

BACKGROUND With the continued demand for new, effective, and safe endodontic therapies, the aim of this study was assessment of efficiency of the ethyl acetate (EthOAc) extract of Tanacetum vulgare (L.) against Candida albicans. MATERIAL AND METHODS The antifungal effectiveness of the EthOAc extract of T. vulgare was determined using the agar disk diffusion method. The inhibition zones induced by the EthOAc extract were compared after 5 minutes, 60 minutes, and 24 hours to those induced by standard solutions (2% chlorhexidine, saturated calcium hydroxide, and 2% sodium hypochlorite). Statistical analysis of the results was performed using the Kruskal-Wallis test and one-way ANOVA. RESULTS The inhibition zone of chlorhexidine against C. albicans was 30.3-19.3 mm, but in combination with EthOAc extract (100 mg/mL) of T. vulgare, this inhibition was from 32.7-30 mm, indicating that this combination exerted a marked synergistic effect against C. albicans. The inhibition zone of sodium hypochlorite (69.7-65 mm) was higher than the inhibition zone of EthOAc extract and chlorhexidine. The combination of EthOAc extract with sodium hypochlorite resulted in a loss of antifungal activity. Furthermore, the activity of the EthOAc extract against C. albicans was decreased after mixing the extract with dentine at a concentration of 25 mg/50 µL (30.3-20.7 mm). The EthOAc extract did not show a genotoxic effect on lymphocyte cells. CONCLUSIONS The EthOAc extract of T. vulgare may be a useful tool to discover natural bioactive agents that have antifungal activity against C. albicans and could be used as endodontic therapies.

Aroma characterization of a wild plant (Sanguisorba albanica) from Kosovo using multiple headspace solid phase microextraction combined with gas chromatography-mass spectrometry-olfactometry.

A wild plant (Sanguisorba albanica) from Kosovo exhibits an appealing aroma, which was perceived as intensely fresh, green, and slightly sweetish with hints of cucumber, melon, and green tea. The characteristic aroma of S. albanica was analyzed for the first time by employing advanced molecular sensory techniques coupled with multiple headspace solid phase microextraction (MHS-SPME). Thirty-six different odor impressions were perceived, and 34 corresponding compounds were identified by a gas chromatography system equipped with a mass spectrometric detector and an olfactory detection port. By aroma dilution analysis, sixteen key odorants with flavor dilution factors higher than 16 were identified. Their respective concentrations were quantified by means of MHS-SPME according to the determined ß values (0.43-0.83), and odor activity values (OAVs) were calculated. (E,Z)-2,6-Nonadienal (green, melon-like, and sweetish odor; OAV 20,046), followed by linalool (floral and citrus-like odor; OAV 10,563), (Z)-6-nonenal (cucumber-like, green, and melon-like odor; OAV 4200), ethyl isobutyrate (floral and fruity odor; OAV 1315), and (E)-2-nonenal (green and fatty odor; OAV 1062) were representative odorants contributing to the overall aroma of S. albanica. Differences between stems, leaves, and flowers of S. albanica with regard to the key odorants were also presented. Intensely green and floral aromas of the leaves and flowers were greatly attributed to (E,Z)-2,6-nonadienal and linalool, respectively. Apart from these compounds, (Z)-6-nonenal contributed to the overall aroma of the stems as well.

Aflatoxin M1 contamination of raw cow's milk in five regions of Kosovo during 2016.

During February and August 2016 (winter and summer season), 192 samples of raw bulk tank milk have been collected from small dairy farms in five different regions of Kosova (Prishtina, Prizren, Peja, Mitrovica, and Gjilan). These samples were analyzed for aflatoxin M1 (AFM1) contamination level by ultra-high performance liquid chromatography coupled with electrospray ionization triple quadrupole tandem mass spectrometry (UHPLC-ESI-MS/MS). The limit of quantification for AFM1 was 0.02 µg/L and recovery at 0.1-0.5 µg/L was 90-95% (coefficient of variation 15-25%). A total of 74 milk samples (38%) were found to be contaminated with AFM1 and 11 samples (5.7%) slightly exceeded the European Union maximum level of 0.05 µg/L. The maximum AFM1 level was at 0.082 µg/L. There was no relevant difference between summer and winter with regard to AFM1 frequency and levels. Although the frequency of AFM1-positive samples varied between regions, from 7% (Prishtina) to 53% (Prizren), only minor regional differences were observed with regard to average and maximum toxin levels. The high percentage of milk samples which were non-compliant with AFM1 maximum levels indicates that efforts to reduce the contamination levels of aflatoxin B1 in cows feed in Kosovo are necessary.

Molecular docking studies of fused coumarin derivatives as inhibitors of GlcN-6.

The biological activity of heterocyclic compounds depends on their structure, the type of hetero atoms in the ring and on the type of substituents present. In this paper, some heterocyclic compounds with coumarin moieties S1-S5 and novobiocin known as coumarin antibiotic were subjected to the molecular docking studies as important tools for drug discovery. Glucosamine-6-phosphate synthase is selected as a suitable target in this study. In silico studies reveal that all synthesized compounds S1-S5 are good inhibitors of GlcN-6 and the docking results are in agreement with in vitro antibacterial evaluation of compounds S1-S5.

Synthesis and pairing properties of oligodeoxynucleotides containing bicyclo-RNA and bicyclo-ANA modifications.

The synthesis of the ribo(bc-rT)- and arabino(bc-araT)-version of bicyclothymidine (bc-dT) has been achieved. A conformational analysis by X-ray and/or (1)H NMR spectroscopy on the corresponding 3',5'-benzyl-protected nucleosides featured a rigid C(2')-endo conformation for the furanose ring, irrespective of the configuration of the OH group at C(2'). The conformation of the carbocyclic ring in these nucleosides was found to be less defined and thus more flexible. Both nucleosides were converted into the corresponding phosphoramidites and incorporated into oligodeoxynucleotides by standard DNA chemistry. T(m)-data of duplexes with cDNA and RNA revealed that a bc-rT unit strongly destabilized duplexes with cDNA and RNA by 6-8 °C/mod, while bc-araT was almost T(m) neutral. A rationale based on a previous structure of a bc-DNA mini duplex suggests that the strong destabilization caused by a bc-rT unit arises from unfavorable steric interactions of the equatorial 2'-OH group with the sugar residue of the 3'-neighboring nucleotide unit.