جستجوی مقالات مرتبط با کلیدواژه "taxus baccata l" در نشریات گروه "پزشکی"

Diseases caused by various drug-resistant strains in plants are increasing in many countries, so many efforts have been made to find new compounds as a suitable alternative to chemical drugs and pesticides. In this study, the antimicrobial effect of essential oils and ethanolic extracts of 10 medicinal plants were investigated on Rathayibacter tritici and Xanthomonas translucens.

 Alcoholic extracts of medicinal plants were extracted using a rotary apparatus. Two standard bacteria R. tritici and X. translucens were prepared from Persian Type Culture Collection. The minimum inhibitory concentration and the minimum inhibitory concentration of essential oils and ethanolic extracts of plants used at a concentration of 50 mg/ ml were determined by dilution in liquid medium on pathogens.

Based on the results, the lowest inhibitory concentration of thyme essential oil was 6.25 ppm, which was inhibited by R. tritici, and the lowest concentration of Hypericum perforatum essential oil against X. translucens was 6.25 ppm. The lowest concentrations of essential oils of yew and fennel were 6.25 ppm, which were inhibited by both bacteria. Rubia tinctorum leaf essential oil in a concentration of 6.25 only inhibited R. tritici bacteria. The antibacterial properties of the essential oils of the studied plants were higher than the extract.

Essential oils of yew and oleander were the most effective against R. tritici and X. translucens, followed by thyme and rosemary against R. tritici and herring flower against X. translucens.  Although the clinical use of ethanolic extracts and essential oils of the studied plants seems valuable due to side effects, but for the clinical use of essential oils and extracts, more research should be done on the mechanism of action of effective compounds of these plants on microbial agents.

 Continuous and indiscriminate use of chemical drugs causes resistance to microorganisms, which in turn weakens the effect of drugs. This adverse event is associated with an increased number of drugs used by patients and the tendency to use compounds with newer and stronger formulations. Furthermore, the essential oils of several plants contain a significant inhibitory effect on pathogenic microorganisms.

 Hence, the current study intended to evaluate the antimicrobial activity of some medicinal plants on some standard human pathogenic bacteria and Candida albicans fungi isolated from women.

 Leaves of Cichorium intybus L., Hypericum perforatum L., Lavandula angustifolia, Thymus vulgaris L., and Taxus baccata L. were collected and analyzed in the botanical laboratory of the University of Zabol. Then, the ethanolic extract was prepared using 40 g of dried leaves in 400 cc of ethanol. Standard bacteria and fungi were obtained from the center for genetic and biological resources of Iran. To determine the activity of free radical trapping, diphenylpicryl hydrazyl was used, and then the antimicrobial effects were investigated by diffusion method in Müller-Hinton agar medium using 6 mm paper disks according to the Bauer and Kirby instructions. Statistical calculations were administered using Statistx Ver10. Mean comparisons were performed using the LSD at the 1% level, and Excel was also used to draw the shapes.

 The diameter of the inhibitory zone of plant extracts against standard bacteria and clinical fungi of Candida albicans at a dilution of 100 ppm was analyzed, which revealed different effects (P < 0.01). Taxus baccata L., with a 15 mm diameter growth zone, showed the highest effect on inhibiting the growth of Bacillus cereus and Pseudomonas aeruginosa. Hypericum perforatum L. with a diameter of 15 mm was found as the most useful plant in inhibiting Shigella dysentery., with a diameter of 10 mm, was the most useful plant in inhibiting the growth of Escherichia coli. The Taxus baccata L., with a maximum growth inhibition zone diameter (20 mm), has been the most effective plant against Candida albicans.

 Considering the side effects of chemical drugs and antibiotics as well as the significant effect of medicinal plant extracts used in this study, the Taxus baccata L. was the most useful plant on inhibiting Candida albicans, Bacillus cereus, and Pseudomonas aeruginosa. Moreover, Hypericum perforatum L. was found as the most useful plant to control the growth of Escherichia coli.

Taxol (Paclitaxel) has been highly recommended to control and treat a wide range of cancers. Taxus baccata L. is primary and natural origin of Taxol.

Due to severe restriction and prohibition of cutting T. baccata, the alternative way for Taxol production is to apply in vitro culture method which was implemented at the current study. Here, for the first time, the effect of amino acid complex as elicitor along with chitosan in cell suspension culture ofT. baccata for enhancing Taxol production was studied.

Young leaves of T. baccata as explants were cultured in different callus induction treatments. At the next step, the calli from the best callus induction treatment were transferred to cell suspension cultures containing chitosan and amino acid complex alone or in combination with each other. Taxol content in treatments were measured by HPLC.

MS medium supplemented with 2,4-D at 2 mg/L and NAA at 1 mg/L proved to be the best treatment of callus induction (100 %), fresh weight (495 mg) and dry weight (272 mg) of calli. Also, HPLC analysis confirmed the maximum production of Taxol (1.96 mg/g) in MS medium having 2 ml/L amino acids complex with 10 mg/L chitosan.

Applying amino acid complex as elicitor with chitosan is suggested for enhancing Taxol production in cell suspension culture of T. baccata.

In this study, the mycosynthesis of silver nanoparticles was investigated using the endophytic fungi isolated from Taxus baccata L. (Iranian Yew).
Endophytic fungi were isolated from Taxus baccata L. (Iranian Yew) and were subjected to mycosynthesis of silver nanoparticles (AgNPs), extracellularly. The characterization of produced AgNPs was done using UV-V spectroscopy, TEM, and FTIR. Further antimicrobial activity of synthesized AgNPs was tested against Bacillus subtillis, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus sp., and Salmonella typhi, using the agar well diffusion assay method. To identify the fungal isolate, the ITS region was amplified by polymerase chain reaction (PCR), using universal primers ITS1 and ITS4. For obtaining closely related phylogenetic sequences, sequence analysis of ITS- rDNA was run using the BLAST algorithm of the NCBI database.
The endophytic fungus, Nemania sp., was found to be a good producer of AgNPs. The surface plasmon resonance band in UV-Vis spectroscopy was at 460 nm, which confirmed the formation of AgNPs. The size range of the synthesized AgNPs was 5 to 70 nm, according to the TEM analysis. The FTIR study of AgNPs showed major peaks around 1035, 1392, 1514, 1644, 2922, and 3443 cm-1, which were responsible for different functional groups possibly involved in the synthesis and stabilization of AgNPs. Antibacterial activity showed maximum zone of inhibition of 17 mm against B. subtilis.
Nemania sp. can be a fungal system for extracellular mycosynthesis of AgNPs, which is a simple and ecofriendly method for nanoparticle synthesis.