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Globe artichoke’s [Cynara cardunculus var. scolymus (L.) Fiori] leaves are rich in polyphenols and due to health-promoting properties artichoke growing has been gaining interest. Optimization and development of valuable bioactive components, which are not in the standard amount in raw material can be achieved and increased with the assistance of in vitro techniques such as callus and subsequently cell suspension cultures. Therefore, in the present study in vitro callogenesis optimization of three globe artichoke cultivars was studied by using 29 different media combinations, based on basic Gamborg B5 medium supplemented with various concentrations of 1-Naphthaleneacetic acid (NAA), 6-Benzylaminopurine (BAP), 2,4-Dichlorophenoxyacetic acid (2,4-D), and Kinetin. Comparisons were made on the basis of using in vivo and in vitro leaves as explant material. In the experiment several parameters such as leaf explants development (%), callus formation (%), and callus weight (g) were assessed for each related cultivar. Results revealed that having auxin: cytokinin concentrations together at enough and well-balanced, having equal amounts or 10:1 concentrations of auxin: cytokinin, concentrations in media combinations are indispensable for stimulating the callogenesis in globe artichoke. The findings of the present study clearly revealed that, there were differences among cultivars regarding callus induction by using in vivo and in vitro leaf explants while in vivo leaf explants came into prominence regarding callus formation and weights. It is assumed that the findings of the present study may play a complementary and auxiliary role in several areas such as pharmaceutical engineering of globe artichoke.

Multidrug-resistant bacteria particularly MRSA is well known as a worldwide problem. Since the rate of development of novel antimicrobial agents has been slowed down during the last years, there have been a need for the exploration of alternative solutions for the treatment of resistant bacterial infections. Treatment of infections by bacteriophages (phages) that specifically kill the infecting pathogen, i.e. by the process known as phage therapy, is considered as a possible approach to treat multidrug resistant bacteria. Phage treatment has also been considered to treat Staphylococcus aureus infections. This study was aimed to evaluate the antibacterial and cytotoxic activities of a new lytic phage obtained from clinical MRSA strains. This lytic phage named as f LizAnk was obtained during the phage infectivity studies performed with 13 lysogenic phages against MRSA strains. The antibacterial activity of the f LizAnk phage was determined in vitro in BHI (Brain Heart Infusion) and LB (Leuria Bertani) broths and the in vivo antibacterial activity against MRSA strains and possible cytotoxic effect against mammalian cells were tested on fibroblastic cell cultures (3T3). This study was conducted using 20 MRSA strains isolated from hospitalized patients. Identification of the isolates was performed by conventional methods and methicillin resistance was detected with oxacillin disk diffusion test and mecA gene detection by PCR. The method described by Kaneko et al. [Biosci Biotechnol Biochem 1997; 61(11): 1960-2] was used with some modifications, for induction and isolation of the phages. In vitro studies indicated that this phage killed the six different MRSA strains (in 107 cfu/ml concentrations) in 8 hours, and this powerful lytic effect was similar in both of the liquid media. In vivo studies were performed by using cell cultures prepared in microplates, and the wells have been inoculated with only phage, phage + MRSA mixture, and only MRSA. The cells were then evaluated microscopically as well as by MTT assay which detected alive cells colorimetrically, at 2nd and 24th hours. In our study, the f LizAnk phage did not cause any toxic effect on fibroblast cell cultures, in addition it was observed that the antibacterial effect of the phage against MRSA has proceeded in the cell culture. In conclusion, since the fLizAnk phage described in this study exhibited strong antibacterial activity against MRSA strains and no cytotoxic effect was detected against mammalian cells, it might be safely used alone or in a phage cocktail to treat skin infection caused by MRSA.

Studies on potato (Solanum tuberosum L.) plants have been carried out to plant tissue culture laboratories because of the disease and virulent free seed tubers in field conditions. Since generative production in commercial potato production is not economically massive, production is made more economically with tubers. Jasmonic acid (JA) and its related compounds are newly recognized plant growth regulators and they are known to have effects on many physiological processes. In this study, it was aimed to determine the effects of methyl jasmonate and sucrose on micro tuber formation in potato micropropagation. To serve the purpose the relationships between twelve media combinations (including control medium), varying concentrations of sucrose (3, 6 and 9 %) either alone or in combination with 1.0 ppm or 2.0 ppm methyl jasmonate were investigated. Three different plant parts such as node, shoot eye and primordial tissue wereused as explant sources. Nitsch&Nitsch was used as the basic nutrient medium and plant growth regulators that used in media were constant at 2.5 mg/L BAP + 0.5 mg/L NAA except for control medium. Obtained micro tubers, plantlets and callus formations were recorded and analyzed. Results revealed that, when methyl jasmonate used at 1.0 ppm concentration in media, it had a positive effect on micro tuber formation and can be recommended to use commercially in mass production.

Globe artichoke [Cynara cardunculus var. scolymus (L.) Fiori] growing has gained commercial importance in recent years due to its consumption as food. It has also started to attract attention in pharmaceutics. Due to globe artichoke’s stated importance, growers need large amount of pathogen-free, healthy starting materials for production. Stated material will maximize the yield while minimizing the costs. Hybrid cultivars have uniform in height and maturity and could be harvested concurrently; on the other hand, an open-pollinated cultivar would have useful potential that could be smoothly produced locally at a lower cost. In vitro micropropagation enabling these goals as it serves large scale, fast, reliable and realistic alternative method to classic propagation via offshoots. The aim of the present study was to comparatively evaluate the micropropagation efficiency of two important local open-pollinated (OP) cultivars (‘Bayrampaşa’, ‘Sakız’) and five F1 hybrid cultivars (‘Olympus’, ‘Madrigal’, ‘Sambo’, ‘Green Globe’, ‘Imparator’), on the basis of total subcultures they were subjected to. Various plant growth regulators at various combinations were assessed for in vitro micropropagation and subsequent in vitro rooting. 3/4 basic MS medium supplemented with 0.05 mg  L-1 BA + 0.005 mg L-1 IBA was determined as the best media combination for in vitro micropropagation, while 10.0 mg L-1 IAA + 1.0 g L-1 activated charcoal adding to 1/2 basic MS medium had positive effects on in vitro rooting. According to results, the micropropagation efficiency varied based on cultivar differences and number of subcultures regardless of being OP or F1 hybrid. The present study demonstrated that in vitro propagation of globe artichoke could be a valuable process for assessing mass propagation regardless of using F1 or OP cultivars. Considering the OP cultivars are cheap in terms of price in a comparison to F1 hybrid cultivars, OP cultivars could be also recommended to be used for in vitro mass propagation.

From the four known isoforms of the staphylococcal exfoliative toxins (ETs), only ETA and ETB are the major causative agents. General knowledge is that the gene for ETA is located on the chromosome, whereas that for ETB is located on a large plasmid. Yoshizawa and co-workers (2000, Microbiol. Immunol. 44(3): 189-191) isolated, for the first time, a temperate phage (φETA) that carried the structural gene for ETA from an ETA-producing strain of Staphylococcus aureus. In this study, we presented eta gene encoding temperate phages isolated from methicillin-resistant S.aureus (MRSA) isolates obtained from patients in a Turkish hospital. Molecular analysis of the phage genome revealed that the eta gene is located upstream to amidase and holin genes, the same as in the φETA genome. However, partial sequence analysis of amidase and holin genes revealed polymorphic variation. In addition to polymorphic variation, restriction fragment length polymorphism (RFLP) analysis of all of the phage genomes showed that the ETA-containing phage is different from the rest of the phage genomes. The phylogenetic dendrogram of pulsed field gel electrophoresis (PFGE) analysis showed that the ETA-carrying MRSA is quite different from the rest of the MRSA strains. This is the first report showing that a MRSA strain carries an ETA-encoding phage.

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Artichoke, belongs to the family Asteraceae (Compositae), is cultivated in a very wide area in the world and regarded as a functional food due to the bioactive components. The propagation of artichoke via tissue culture offers considerable advantages. However one of the most important problem is in vitro rooting. Therefore, the main purpose of the present study was to develop an effective protocol on in vitro rooting of 'Bayrampaşa' cultivar which is one of the important local artichoke cultivar. To serve the purpose, after a successful micropropagation process, involving 3 subculture stages, well-developed plantlets were selected and rooted in different media compositions as ten different media including control group were used in present study. The differences between the media were provided by adding different growth regulators such as 10.0 mg l-1 indole-3-acetic acid (IAA), 6.0 mg l-1 indole butyric acid (IBA), 5.0 mg l-1 gibberellic acid (GA3), 0.5 mg l-1 naphthaleneacetic acid (NAA) and activated charcoal (0, 1.0 and 2.0 g l-1). Developments of plantlets were observed and recorded at 15 days intervals. According to the results obtained during the study, the medium containing IAA (10.0 mg l-1) and 1.0 g l-1 of activated charcoal gave the best results in terms of rooting after micropropagation.