Microwave heating as a novel route for obtaining carbon precursors from anthracene oil

This work describes a novel route for the preparation of pitches by oxidative polymerization of an industrial anthracene oil (AO) in a microwave semi-pilot equipment consisting in a multimode applicator having a 2.45 GHz magnetron with variable microwave power. The experimental five variables of microwave heating of AO air-blowing range between 320-380 ˚C (temperature), 0.2 - 3.9 ˚C min-1 (heating rate), 1.5 - 5 h (soaking time), 16 – 20.5 % (air/AO ratio ) and 200 – 1500 g (initial weight). Their effect on the overall microwave air-blowing process is evaluated by means of a statistical analysis. A detailed characterization of the pitches has been carried out in terms of ultimate analysis, softening point, solubility parameters (toluene insolubles (TI) and quinoline insolubles (QI)) and thermogravimetric analysis. The experiments were also carried out by using conventional heating for comparative purposes. The detailed study of the electric energy consumption of the overall microwave treatment allows estimating a significant electric energy saving of about 20 % when compared to conventional heating thus representing an excellent result in the production of carbon precursors

Survival of lichens and bacteria exposed to outer space conditions - Results of the Lithopanspermia experiments

n the space experiments Lithopanspermia, experimental support was provided to the likelihood of the lithopanspermia concept that considers a viable transport of microorganisms between the terrestrial planets by means of meteorites. The rock colonising lichens Rhizocarpon geographicum and Xanthoria elegans, the vagrant lichen Aspicilia fruticulosa, and endolithic and endoevaporitic communities of cyanobacteria and bacteria with their natural rock substrate were exposed to space for 10 days onboard the Biopan facility of the European Space Agency (ESA). Biopan was closed during launch and re-entry. In addition, in the Stone facility, one sample of R. geographicum on its natural granitic substrate was attached at the outer surface of the re-entry capsule close to the stagnation point, only protected by a thin cover of glass textolite. Post-flight analysis, which included determination of the photosynthetic activity, LIVE/DEAD staining, and germination capacity of the ascospores, demonstrated that all three lichen were quite resistant to outer space conditions, which include the full spectrum of solar extraterrestrial electromagnetic radiation or selected wavelength ranges. This high resistance of the lichens to space appears to be due to their symbiotic nature and protection by their upper pigmented layer, the cortex. In contrast, the rock- or halite-inhabiting bacteria were severely damaged by the same exposure. After atmospheric re-entry, the granite of the Stone sample was transformed into a glassy, nearly homogenous material, with several friction striae. None of the lichen cells survived this re-entry process. The data suggest that lichens are suitable candidates for testing the concept of lithopanspermia, because they are extremely resistant to the harsh environment of outer space. The more critical event is the atmospheric re-entry after being captured by a planet. Experiments simulating the re-entry process of a microbe-carrying meteoroid did not show any survivors

Differential Expression of Fungal Genes Determines the Lifestyle of Plectosphaerella Strains During Arabidopsis thaliana Colonization

16 Päg.The fungal genus Plectosphaerella comprises species and strains with different lifestyles on plants, such as P. cucumerina, which has served as model for the characterization of Arabidopsis thaliana basal and nonhost resistance to necrotrophic fungi. We have sequenced, annotated, and compared the genomes and transcriptomes of three Plectosphaerella strains with different lifestyles on A. thaliana, namely, PcBMM, a natural pathogen of wild-type plants (Col-0), Pc2127, a nonpathogenic strain on Col-0 but pathogenic on the immunocompromised cyp79B2 cyp79B3 mutant, and P0831, which was isolated from a natural population of A. thaliana and is shown here to be nonpathogenic and to grow epiphytically on Col-0 and cyp79B2 cyp79B3 plants. The genomes of these Plectosphaerella strains are very similar and do not differ in the number of genes with pathogenesis-related functions, with the exception of secreted carbohydrate-active enzymes (CAZymes), which are up to five times more abundant in the pathogenic strain PcBMM. Analysis of the fungal transcriptomes in inoculated Col-0 and cyp79B2 cyp79B3 plants at initial colonization stages confirm the key role of secreted CAZymes in the necrotrophic interaction, since PcBMM expresses more genes encoding secreted CAZymes than Pc2127 and P0831. We also show that P0831 epiphytic growth on A. thaliana involves the transcription of specific repertoires of fungal genes, which might be necessary for epiphytic growth adaptation. Overall, these results suggest that in-planta expression of specific sets of fungal genes at early stages of colonization determine the diverse lifestyles and pathogenicity of Plectosphaerella strains.This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) grant BIO2015-64077-R and the Spanish Research Agency (AEI) grant RTI2018-096975-B-I00 to A. Molina and by the “Severo Ochoa Programme for Centers of Excellence in R&D” grant SEV-2016-0672 (2017-2021) to the CBGP (UPM-INIA). In the frame of SEV-2016-0672 program, H. Mélida was supported with a postdoctoral contract. A. Muñoz-Barrios was financially supported by the Universidad Politécnica de Madrid (UPM) Ph.D. students PIF program, I. del Hierro was a FPU fellow (Spanish Ministry of Education, Culture and Sports grant FPU16/07118), V. Fernández-Calleja was supported by the Consejería de Educacíon e Investigacíon of Comunidad de Madrid YEI program for postdoctoral researchers (PEJD-2016/BIO-3327), and the work was further supported through a Comunidad de Madrid YEI program for laboratory technicians grant (PEJ16/BIO/TL-1570).Peer reviewe

Correlation of sequential floral development and male gametophyte development and preliminary results on anther culture in Opuntia ficus-indica.

Before approaching anther culture as a tool to trigger an androgenic response in a new species, it is advisable to characterize and correlate flower and male gametophyte development to enable reproducible identification of the appropriate starting material. Buds and flowers of Opuntia ficus-indica cv. Gialla were classified in eight stages according to their total length at the earlier stages and the length of the corolla in flowers with emerging sepals. Due to the low condensation of chromatin in the microspore nucleus as well as in the vegetative nucleus of the bi- and tricellular pollen along with the high autofluorescence of the intricate exine, DAPI staining turned out not to be feasible in this species. Therefore an approach based on light-microscopy observation of semithin sections was used. These sections were stained with toluidine blue for general structure recognition and I2KI to study starch deposition. Correlations were made between the sequential floral and male gametophyte development. Using this approach we determined the timing of pollen formation and observed that pollen development is impaired in plants producing seedless fruits. Furthermore, anther culture was carried out with anthers collected from flower buds at stages 2 and 3. Most of the anthers produced callus, however no regeneration was obtained