24 research outputs found
EvoluciĂłn del comportamiento de los diferentes tipos polĂnicos en la atmĂłsfera de Málaga (1991-2015): Su relaciĂłn con los parámetros meteorolĂłgicos y cambio climático
Fecha de lectura de Tesis: 27 de julio de 2018.En la presente tesis se ha estudiado una base de datos correspondiente a un periodo de 25 años (1991-2015) de los registros de polen en la atmĂłsfera de Málaga, obtenidos mediante un captador volumĂ©trico de tipo Hirst ubicado en la azotea de la Facultad de Ciencias, siguiendo los protocolos estandarizados por la Red Española de AerobiologĂa. Se han estudiado las concentraciones de polen y evaluado las posibles tendencias observadas en la mayorĂa de los tipos polĂnicos registrados, centrándonose tanto en la dinámica estacional como intradiaria. Se han analizado dichas tendencias en una serie de parámetros como son: Ăndice polĂnico anual (IPA); inicio, final y duraciĂłn del periodo principal de polinaciĂłn (PPP); fecha del dĂa pico y concentraciĂłn media diaria máxima alcanzada en dicho dĂa. Para ello se ha realizado un análisis de las tendencias observadas mediante pruebas paramĂ©tricas de regresiĂłn lineal simple, pero tambiĂ©n se ha utilizado la prueba no paramĂ©trica Mann-Kendall. Además, se han evaluado las correlaciones estadĂsticas entre la concentraciĂłn de polen y los valores de los diferentes parámetros meteorolĂłgicos, utilizando conjuntos de datos diarios a largo plazo para 13 tipos de polen principales (7 árboles y 6 plantas herbáceas). Por otra parte, se han establecido modelos de pronĂłstico para estimar las concentraciones medias diarias de polen mediante análisis de regression lineal mĂşltiple por pasos. Por Ăşltimo, se ha establecido un calendario polĂnico actualizado, utilizando los datos del periodo 1992-2015
The use of cyclohexane as a new adhesive for airborne pollen sampling
Se estudia la adherencia del fluido de silicona, utilizando como disolvente el ciclohexano en lugar del tetracloruro de carbono, como se venĂa haciendo anteriormente. Se comparan los resultados entre ambos disolventes en un captador aerobiolĂłgico de tipo Hirst.Carbon Tetrachloride, used as a solvent for the silicone adhesive in airborne pollen sampling, has been recently interdicted by the Registration Evaluation Authorization of Chemicals (REACH) protocol due to its dangerous effects on environment and human health (Manibusan et al. 2007) and it will no longer be produced. Therefore, the need to find a new solvent for the silicon-coating solution is mandatory in order to continue aerobiological research. In a previous study, Thibaudon et al. (2014) concluded that there were no-significant differences between Diethyl Ether and Carbon Tetrachloride and the first can be used as solvent for capturing airborne pollen. The importance of this topic led us to investigate the efficiency of other solvents to use alternatively for the adhesive coating solution. The aim of this preliminary study is to compare the efficiency of airborne pollen grain capture on silicone fluid by using Cyclohexane solvent as an alternative to Carbon Tetrachloride, the solvent used by the Spanish Aerobiology Network (REA). The study was carried out in Malaga (southern Spain), from 16 February to 26 April, 2015 (10 weeks), with the aid of a 7-day Hirst type volumetric trap, located on the roof of the Faculty of Science, 15 m above ground level. For this, the drum was covered by a Melinex tape, coated with silicone adhesive containing two different solvents: one half of the tape with Carbon Tetrachloride and the other half with Cyclohexane, following the methodology previously described by Thibaudon et al. (2015). The position of the two sampling adhesives was reversed from right to left every week. The counting method consisted of 2 continuous horizontal sweeps per each half of the tape (Galán et al., 2007). The results obtained, expressed as number of pollen grains/m3, will be statistically analyzed in order to detect possible differences, if any. Finally, the results, regarding total pollen as well as the different pollen types, separately, will be presented in order to propose or not Cyclohexane as an alternative solvent to Diethyl Ether and Carbon Tetraclorhidre, more dangerous substances from a toxic point of view (Toxicology Data Network, TOXNET, http://toxnet.nlm.nih.gov/).Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Atmospheric pollen dynamics in Malaga (s. Spain) during 2013-2014. Seasonal trends
In this work we present the atmospheric pollen results obtained in Malaga, a coastal Mediterranean city situated in southern Spain, throughout 2013 and 2014. The main objective is to compare the results obtained these years with those registered during the 21 previous years (1992-2012) and detect possible significant trends.
The samplings were made with the aid of a Hirst-type volumetric pollen trap (Hirst, 1952) situated on the roof of the building of the Faculty of Sciences, Campus de Teatinos. The mounting of the samples and the pollen counting were according to the methodology proposed by the Spanish Aerobiology Network, the REA (Galán et al., 2007).
In this work, the seasonal evolution of the different taxa, annual pollen index and features of the main pollen season (length and start, end and peak days) are studied and the results obtained in 2013 and 2014 are compared to the average values of the previous years in order to detect differences related to climate change. The annual mean temperature have been rising in 2013 and 2014 (19.1 and 19.9ÂşC) comparing to the average of the last 20 years (18.7ÂşC). The annual total rainfall have been declining in 2013 and 2014 (354.7 and 373.1 mm) comparing to the average of the last 20 years (546.2 mm). The relative humidity declined in 2014 (60.6%) compared to last 20 years (66.6%). Among the significant trends that we have observed are: increase in the annual pollen index of Quercus and Olea, decrease in the annual pollen index of Chenopodiaceae, Plantago and Cyperaceae, delay in the end and increase in the length of the main pollen season of Quercus, delay and reduction in the length of the main pollen season of Gramineae pollen.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tec
Tendencias aerobiolĂłgicas en táxones arbĂłreos como consecuencia del cambio climático. Málaga (AndalucĂa) como caso de estudio.
La temperatura media de la Tierra ha aumentado 0,65ÂşC desde 1951, aunque este incremento....Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
First volumetric records of airborne Cladosporium and Alternaria spores in the atmosphere of Al Khor (northern Qatar): a preliminary survey
Daily monitoring of airborne fungal spores was carried out for the first time in Al Khor city, Qatar, using a Hirst type 7-day recording volumetric spore trap, from May 2017 to May 2019. During the sampling period, the annual and monthly fluctuations, as well as intradiurnal variations of airborne fungal spore concentrations, were evaluated. Cladosporium, followed by Alternaria, were the spore types most abundant in the atmosphere of the city, with a strong interannual variability in the atmospheric concentrations being observed. The Annual Spore Integrals (ASIns) were 3334 and 1172 spore * day/m3 (2017–2018), and 6796 and 1538 spore * day/m3 (2018–2019) for Cladosporium and Alternaria, respectively. Total daily spore concentrations showed significantly positive correlations with mean, minimum, and maximum temperatures but significantly negative correlations with relative humidity. However, due to the scarce rainfalls’ days, we did not find a statistically significant correlations between Cladosporium and Alternaria spore concentrations and this parameter. Despite this, the spore peaks were strongly related to precipitations that occurred during the previous month. In general, no significant correlations were found with wind speed but, regarding wind direction, the higher percentage of spores were collected when wind blows from the 4th quadrant (NW). According to the intradiurnal pattern, Cladosporium fungal spores displayed their maximum daily concentration during 8:00–10:00 h in the morning, with a second peak in the afternoon, while for Alternaria, the maximum peaks were observed between 08:00 and 14:00 h. Because no consistent previous aerobiological studies exist from Qatar, the aim of this study is to define the seasonality and intradiurnal behaviour of these two airborne fungal spore and the role that, in such arid scene, the meteorological parameters play on the spore concentrations.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Funding for open access charge: Universidad de Málaga / CBUA. We declare that the research reported in this manuscript received supported grant funding from the Qatar National Research Fund (QNRF)-Qatar (Project NPRP 9–241-3–043)
Isolation of a Chitinolytic Bacillus licheniformis S213 Strain Exerting a Biological Control Against Phoma medicaginis Infection
Among nine chitinase-producing strains isolated from Tunisian soil, one isolate called S213 exhibited a potent chitinolytic activity. S213 strain was identified as Bacillus licheniformis by API 50CH system and sequence analysis of its partial 16S ribosomal DNA. Chitinolytic activity was induced either by colloidal chitin or fungal cell walls, and the highest chitinase activity reached at the late stationary phase exhibiting optimal temperature and pH of 50-60°C and pH6.0, respectively. SDS-PAGE analysis of the secreted colloidal chitin-induced proteins showed a major protein of about 65kDa. This protein was identified as chitinase on the basis of its peptide sequences which displayed high homology with chitinase sequence of B. licheniformis ATCC 14580. Moreover, chitinolytic activity containing supernatant inhibited the growth of several phytopathogenic fungi including Phoma medicaginis. Interestingly, S213 strain reduced efficiently the damping-off disease caused by P. medicaginis in Medicago truncatula and should be envisaged in enzyme-based biopesticides against phytopathogen application
Utilization of Grape Seed Flour for Antimicrobial Lipopeptide Production by Bacillus amyloliquefaciens C5 Strain
International audienceAn endophytic Bacillus amyloliquefaciens strain called C5, able to produce biosurfactant lipopeptides with a broad antibacterial activity spectrum, has been isolated from the roots of olive tree. Optimization of antibacterial activity was undertaken using grape seed flour (GSF) substrate at 0.02, 0.2, and 2% (w/v) in M9 medium. Strain C5 exhibited optimal growth and antimicrobial activity (MIC value of 60 ÎĽg/ml) when incubated in the presence of 0.2% GSF while lipopeptide production culminated at 2% GSF. Thin layer chromatography analysis of lipopeptide extract revealed the presence of at least three active spots at Rf 0.35, 0.59, and 0.72 at 0.2% GSF. Data were similar to those obtained in LB-rich medium. MALDI-TOF/MS analysis of lipopeptide extract obtained from 0.2% GSF substrate revealed the presence of surfactin and bacillomycin D. These results show that GSF could be used as a low-cost culture medium supplement for optimizing the production of biosurfactants by strain C5
Purification and characterization of a novel high molecular weight alkaline protease produced by an endophytic Bacillus halotolerans strain CT2
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Antioxidative and DNA Protective Effects of Bacillomycin D-Like Lipopeptides Produced by B38 Strain
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