Physiological and biochemical aspects of propagation in endemic species Micromeria pulegium (Rochel) Benth. and Micromeria croatica (Pers.) Schoot in vitro

aromatičnih biljaka koje se koriste u tradicionalnoj medicini, hortikulturi, hemijskoj, prehrambenoj i kozmetičkoj industriji. Retke, endemične i/ili ugrožene vrste familije Lamiaceae predstavljaju poseban izazov za proučavanje, prevashodno u cilju očuvanja specijskog diverziteta i njihovih populacija u prirodi, ali i zato što su izvor važnih bioaktivnih molekula raznovrsnog dejstva (antimikrobna, antvirusna, fungicidna, antioksidantna, citotoksična, alelohemijska, insekticidna aktivnost, itd.) i potencijalno široke primene. Usled izrazite heterogenosti, predstavnici roda Micromeria su bili često predmet taksonomskih diskusija. Pripadnike sekcije Pseudomelissa gde spada i М. pulegium, nakon molekularno genetičkih analiza hloroplastne DNK, Brauchler (2005) premešta u rod Clinopodium. Ipak, u ovoj tezi je primenjen tradicionalni taksonomski koncept, predložen od strane Harley-a i sar. (2004), koji podržava homogenost roda Micromeria, pri čemu je sect. Pseudomelissa njegova sastavna jedinica. U skladu sa primenjenim sistemom dve istraživane vrste su klasifikovane u idividualne sekcije roda: Micromeria sect. Micromeria (M. croatica), odnosno Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium predstavlja endemičnu vrstu Južnih Karpata u Rumuniji, sa enklavom u istočnoj Srbiji, a Micromeria croatica balkansku endemičnu vrstu čiji se areal vezuje pre svega za planinski venac Dinarida. Njihove prirodne populacije imaju mali broj jedinki i nastanjuju staništa koja su pod negativnim uticajem antropogenih faktora. Imajući u vidu značaj roda Micromeria, kao i činjenicu da su pomenute vrste retke i ugrožene, javila se potreba da se one gaje zarad očuvanja i istraživanja bez pritiska na prirodne populacije i bez remećenja prirodnog genofonda. Iz pomenutih razloga obe vrste roda Micromeria uvedene su kulturu biljnih tkiva in vitro. U ovoj disertaciji vršeno je ispitivanje efekata regulatora rastenja na morfogenezu i produkciju etarskih ulja endemičnih vrsta M. pulegium i M. croatica in vitro...Plants from Lamiaceae family are prominent representatives of the edible, medicinal or aromatic herbs used in traditional medicine, horticulture, chemical, cosmetic and food industry. The rare, endemic and/or threatened species from family Lamiaceae pose a special challenge for studying, primarily in order to preserve species diversity and their populations in the wild, but also as they are source material for important bioactive molecules with diverse activity (antimicrobial, antiviral, fungicidal, antioxidant, cytotoxic, allelochemical, insecticidal and other types of activity) and potential broad spectrum of use. Due to the pronounced heterogeneity, representatives of genus Micromeria used to be a common topic of taxonomic discussions. After the molecular-genetic analyses of chloroplast DNA, Brauchler (2005) has transferred the representatives of section Pseudomelissa, which includes М. pulegium, into the genus Clinopodium. However, this thesis is using the traditional taxonomic concept suggested by Harley et al. (2004), supporting the homogeneity of genus Micromeria, where sect. Pseudomelissa remains its integral unit. According to this system the two studied species were classified within the individual sections of the genus: Micromeria sect. Micromeria (M. croatica) and Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium represents an endemic species of Southern Carpathians in Romania, with an enclave in Eastern Serbia, while Micromeria croatica is an endemic Balkan species primarily connected with the mountain chain of Dinarides. Their natural populations are characterized by a small number of individuals inhabiting habitats under the negative influence of anthropogenic factors. Due to the importance of genus Micromeria and the fact that these two species are rare and threatened, a need arose to grow them in captivity so they may be preserved and studied without additional pressure on natural populations and without disturbance of the natural gene pool. For these reasons both species of genus Micromeria were introduced in plant tissue culture in vitro..

Factors influencing axillary bud induction on nodal segments of Micromeria pulegium (Rochel) Benth.

Micromeria pulegium (Rochel) Benth.is an endemic species from family Lamiaceae. Plants from this family are characterized by presence of secondary metabolites and antioxidant components. M. pulegium contains pulegone which is a potential bio-insecticide and a bio-pesticide. Natural populations of this species are so small that there is a need for an alternative way of propagate and proliferation of individuals. Method of micropropagation was used with the goal of mass production of plants with the chemical composition of essential oils as similar as possible to that in wild-harvested plants. This paper presents the study on influence of concentration of mineral salts, carbon sources (sucrose and maltose) and nitrogen source (casein hydrolysate) on process of in vitro regeneration of plants through induction of axillary buds on the nodal segments of Micromeria pulegium. The greatest number of axillary buds was formed in explants grown on MS culture medium with 3 % sucrose and 500 mg/L casein hydrolysate

Comprehensive review of the structural behaviour and numerical modelling of recycled aggregate concrete-filled steel tubes

This paper summarises current research findings related to the behaviour and simulation of a relatively new type of structural component: recycled aggregate concrete-filled steel tube columns (RACFST). The first part of the paper presents a review of the latest experimental campaigns on RACFST columns subjected to a variety of loading conditions. For each of loading condition, highlight observations about the behaviour of RACFST columns are presented. The second part of the paper provides a summary of numerical modelling approaches developed for simulating the structural behaviour of RACFST columns. Special attention is paid to the selection and calibration of material models for recycled aggregate concrete. Finally, directions for future investigations in this area are outlined and discussed. The review will benefit researchers and professionals seeking to gain an indepth understanding of the behaviour of RACFST columns, and fills a gap in existing literature regarding a number of practical issues related to the numerical modelling of these components

Comparative Analysis of Different Methods for Graphene Nanoribbon Synthesis

Graphene nanoribbons (GNRs) are thin strips of graphene that have captured the interest of scientists due to their unique structure and promising applications in electronics. This paper presents the results of a comparative analysis of morphological properties of graphene nanoribbons synthesized by different methods. Various methods have been reported for graphene nanoribons synthesis. Lithography methods usually include electron-beam (e-beam) lithography, atomic force microscopy (AFM) lithography, and scanning tunnelling microscopy (STM) lithography. Sonochemical and chemical methods exist as well, namely chemical vapour deposition (CVD) and anisotropic etching. Graphene nanoribbons can also be fabricated from unzipping carbon nanotubes (CNTs). We propose a new highly efficient method for graphene nanoribbons production by gamma irradiation of graphene dispersed in cyclopentanone (CPO). Surface morphology of graphene nanoribbons was visualized with atomic force and transmission electron microscopy. It was determined that dimensions of graphene nanoribbons are inversely proportional to applied gamma irradiation dose. It was established that the narrowest nanoribbons were 10-20 nm wide and 1 nm high with regular and smooth edges. In comparison to other synthesis methods, dimensions of graphene nanoribbons synthesized by gamma irradiation are slightly larger, but the yield of nanoribbons is much higher. Fourier transform infrared spectroscopy was used for structural analysis of graphene nanoribbons. Results of photoluminescence spectroscopy revealed for the first time that synthesized nanoribbons showed photoluminescence in the blue region of visible light in contrast to graphene nanoribbons synthesized by other methods. Based on disclosed facts, we believe that our synthesis method has good prospects for potential future mass production of graphene nanoribbons with uniform size, as well as for future investigations of carbon nanomaterials for applications in optoelectronics and biological labeling

Essential oils as potential biocontrol products against plant pathogens and weeds: in vitro culture approach

Secondary metabolism in plant plays a major role in the survival of the plant in its ecosystem, mediating the interaction of the plant with its environment. Plant bioactive compounds are biosynthesized as a defensive strategy of plants in response to natural perturbations. A number of biological effects have been associated with the main monoterpenoids detected in investigated Micromeria spp. and Clinopodium spp. essential oils. One alternative for the production of these prospective biocontrol products is in vitro plant tissue culture. Our data suggest that the metabolic potential of in vitro shoot cultures of selected species can be manipulated by varying in vitro culture conditions.“XXVII Savetovanje o biotehnologiji sa međunarodnim učešćem"”, Čačak, 25 - 26. mart 2022. godineSaopštenje je štampano u celosti

A Comparison of MGMT Testing by MSP and qMSP in Paired Snap-Frozen and Formalin-Fixed Paraffin-Embedded Gliomas

Comparative analysis of the conventional methylation-specific PCR (MSP) vs. the quantitative MSP (qMSP) assessment of the O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in 34 snap-frozen (SF) glioma samples was performed. The accuracy of the semi-quantitative MSP was compared with the corresponding qMSP semi-quantitative values using two semi-quantitative cut-off values (0—unmethylated and 1—weakly methylated) to discriminate methylated from unmethylated samples. In the case of the cut-off value 0, MSP test showed 80.0% sensitivity and 78.9% specificity compared to the reference qMSP analysis. However, when using the cut-off value 1, the diagnostic accuracy of the MSP test was significantly higher (85.7% sensitivity, 85.2% specificity). Fleiss’ Kappa statistical analyses indicated moderate agreement (Fleiss’ Kappa Coefficient = 0.509; 70.59% agreement) between MSP and qMSP semi-quantitative measurements of MGMT promoter methylation in glioma patients, justifying the conventional MSP use in diagnostics and confirming its high reliability. Further, we aimed to compare the validity of SF and formalin-fixed paraffin-embedded (FFPE) glioma samples for MGMT testing. Statistical analyses indicated moderate overall agreement of FFPE glioma samples and SF MSP semi-quantitative measurements (Fleiss’ Kappa Coefficient = 0.516/0.509; 70.0% agreement) and emphasized their low reliability in the assessment of highly methylated MGMT promoter samples

Antioxidant, Antimicrobial and Antiproliferative Activities of Five Lichen Species

The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA)/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru)/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+) bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells

Physiological and biochemical aspects of propagation in endemic species Micromeria pulegium (Rochel) Benth. and Micromeria croatica (Pers.) Schoot in vitro

aromatičnih biljaka koje se koriste u tradicionalnoj medicini, hortikulturi, hemijskoj, prehrambenoj i kozmetičkoj industriji. Retke, endemične i/ili ugrožene vrste familije Lamiaceae predstavljaju poseban izazov za proučavanje, prevashodno u cilju očuvanja specijskog diverziteta i njihovih populacija u prirodi, ali i zato što su izvor važnih bioaktivnih molekula raznovrsnog dejstva (antimikrobna, antvirusna, fungicidna, antioksidantna, citotoksična, alelohemijska, insekticidna aktivnost, itd.) i potencijalno široke primene. Usled izrazite heterogenosti, predstavnici roda Micromeria su bili često predmet taksonomskih diskusija. Pripadnike sekcije Pseudomelissa gde spada i М. pulegium, nakon molekularno genetičkih analiza hloroplastne DNK, Brauchler (2005) premešta u rod Clinopodium. Ipak, u ovoj tezi je primenjen tradicionalni taksonomski koncept, predložen od strane Harley-a i sar. (2004), koji podržava homogenost roda Micromeria, pri čemu je sect. Pseudomelissa njegova sastavna jedinica. U skladu sa primenjenim sistemom dve istraživane vrste su klasifikovane u idividualne sekcije roda: Micromeria sect. Micromeria (M. croatica), odnosno Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium predstavlja endemičnu vrstu Južnih Karpata u Rumuniji, sa enklavom u istočnoj Srbiji, a Micromeria croatica balkansku endemičnu vrstu čiji se areal vezuje pre svega za planinski venac Dinarida. Njihove prirodne populacije imaju mali broj jedinki i nastanjuju staništa koja su pod negativnim uticajem antropogenih faktora. Imajući u vidu značaj roda Micromeria, kao i činjenicu da su pomenute vrste retke i ugrožene, javila se potreba da se one gaje zarad očuvanja i istraživanja bez pritiska na prirodne populacije i bez remećenja prirodnog genofonda. Iz pomenutih razloga obe vrste roda Micromeria uvedene su kulturu biljnih tkiva in vitro. U ovoj disertaciji vršeno je ispitivanje efekata regulatora rastenja na morfogenezu i produkciju etarskih ulja endemičnih vrsta M. pulegium i M. croatica in vitro...Plants from Lamiaceae family are prominent representatives of the edible, medicinal or aromatic herbs used in traditional medicine, horticulture, chemical, cosmetic and food industry. The rare, endemic and/or threatened species from family Lamiaceae pose a special challenge for studying, primarily in order to preserve species diversity and their populations in the wild, but also as they are source material for important bioactive molecules with diverse activity (antimicrobial, antiviral, fungicidal, antioxidant, cytotoxic, allelochemical, insecticidal and other types of activity) and potential broad spectrum of use. Due to the pronounced heterogeneity, representatives of genus Micromeria used to be a common topic of taxonomic discussions. After the molecular-genetic analyses of chloroplast DNA, Brauchler (2005) has transferred the representatives of section Pseudomelissa, which includes М. pulegium, into the genus Clinopodium. However, this thesis is using the traditional taxonomic concept suggested by Harley et al. (2004), supporting the homogeneity of genus Micromeria, where sect. Pseudomelissa remains its integral unit. According to this system the two studied species were classified within the individual sections of the genus: Micromeria sect. Micromeria (M. croatica) and Micromeria sect. Pseudomelissa (M. pulegium). Micromeria pulegium represents an endemic species of Southern Carpathians in Romania, with an enclave in Eastern Serbia, while Micromeria croatica is an endemic Balkan species primarily connected with the mountain chain of Dinarides. Their natural populations are characterized by a small number of individuals inhabiting habitats under the negative influence of anthropogenic factors. Due to the importance of genus Micromeria and the fact that these two species are rare and threatened, a need arose to grow them in captivity so they may be preserved and studied without additional pressure on natural populations and without disturbance of the natural gene pool. For these reasons both species of genus Micromeria were introduced in plant tissue culture in vitro..

Epidemiološka proučavanja crvenila kukuruza

Redness as a harmful disease on maize has been present in Banat, as well as in some other regions of Serbia, since 1957. Some years the redness of maize was epiphytotic causing considerable reduction of yield of corn, sometimes over 50%. Redness of maize is a peculiar disease. It appears usually at the beginning of July when maize plants approach tasseling. First symptom can be seen as redness of main vein in the leaves near the ear. Later on redness spreads all over leaf blade, than on upper and lower leaves, as well as on stalk and ear of infected plants. The kernels of disesed maize plants, starting from the top of the ear remain empty (not properly filled) and shrivelled. Infected maize plants wilt and dry up early. From maize plants diseased by redness the fastidious bacteria have been extracted. Those bacteria we found in leaf, kernel and adventive roots. Fastidious bacteria were also extracted from Johnson grass (Sorghum halepense) leaf and rhizome, as well as from leaves of Setaria viridis and Taraxacum officinale plants showing symptoms of redness. Maize plants grown under plastic tunnel (controlled space) from the beginning of June until the end of August were not infected and did not show the symptoms of redness. On the other hand, the most infections of maize plants by the cause of redness took place when maize plants were uncovered during the second half of July. In both years of investigations (2004. and 2005.) the redness was present in the surrounding crops of maize. In 2004 32.0% and in 2005 21.5% maieze plants in neighbousing crops showed symptoms of redness.Crvenilo kukuruza javlja se u nekim rejonima Srbije. U određenim periodima to oboljenje ima epifitotičan karakter izazivajući značajne štete u proizvodnji kukuruza. Etiologija i epidemiologija crvenila kukuruza nisu razjašnjene. Tokom ovih istraživanja potvrđena je infektivna priroda crvenila kukuruza, kao i prisustvo fastidioznih bakterija u tkivima obolelih biljaka. Kukuruz gajen u zaštićenom prostoru od početka juna do kraja avgusta ne oboleva od crvenila. Najčešće zaraze su u drugoj polovini jula. Fastidiozne bakterija su ekstrahovane iz lista, zrna i pandži biljaka kukuruza obolelih od crvenila, zatim iz lista i rizoma Sorghum halepense, kao i iz lista Setaria viridis i Taraxacum officinaale sa simptomima crvenila