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3.
Molecules ; 28(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37110787

RESUMEN

Gas chromatography (GC) techniques for analyzing and determining the cannabinoid profile in cannabis (Cannabis sativa L.) are widely used in standard laboratories; however, these methods may mislabel the profile when used under rapid conditions. Our study aimed to highlight this problem and optimize GC column conditions and mass spectrometry (MS) parameters to accurately identify cannabinoids in both standards and forensic samples. The method was validated for linearity, selectivity, and precision. It was observed that when tetrahydrocannabinol (Δ9-THC) and cannabidiolic acid (CBD-A) were examined using rapid GC conditions, the resulting derivatives generated identical retention times. Wider chromatographic conditions were applied. The linear range for each compound ranged from 0.02 µg/mL to 37.50 µg/mL. The R2 values ranged from 0.996 to 0.999. The LOQ values ranged from 0.33 µg/mL to 5.83 µg/mL, and the LOD values ranged from 0.11 µg/mL to 1.92 µg/mL. The precision values ranged from 0.20% to 8.10% RSD. In addition, forensic samples were analyzed using liquid chromatography (HPLC-DAD) in an interlaboratory comparison test, with higher CBD and THC content than GC-MS determination (p < 0.05) in samples. Overall, this study highlights the importance of optimizing GC techniques to avoid mislabeling cannabinoids in cannabis samples.


Asunto(s)
Cannabinoides , Cannabis , Alucinógenos , Cannabis/química , Cannabinoides/química , Alucinógenos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Agonistas de Receptores de Cannabinoides , Dronabinol/química
6.
J Sci Food Agric ; 98(12): 4625-4633, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29516500

RESUMEN

BACKGROUND: Glass frits with a P2 O5 /K2 O ratio equal to 0.65 and different concentrations of SiO2 (6.5-56.0 wt%), CaO (0-5.1 wt%) and Al2 O3 (0-14.6 wt%) have been prepared and analysed as potential glass fertilizers (GF). RESULTS: P2 O5 and K2 O were leached primarily within the first 5 days but the total amount was dependent on the SiO2 /Al2 O3 ratio of the glass frit. Sustained P2 O5 and K2 O leaching for more than 40 days could be obtained if the glass frit contained more than 7% Al2 O3 . A final glass frit composition (29% SiO2 , 5% CaO, 7% Al2 O3 , 30% P2 O5 , 25% K2 O) was selected and used in an experimental tomato crop of 1 ha area, where one half was fertilized with an NPK conventional fertilizer and the other half with the GF fertilizer. CONCLUSION: After harvesting the tomato crops, the GF fertilizer was found to result in a higher yield than the NPK conventional fertilizer: 59980 kg and 74 360 kg for NKP and GF, respectively. The general characteristics of the harvested tomato fruits and leaves were similar in the two cases and the differences fell within statistical error. No differences in any of the soil characteristics were detected as a result of the use of GF. © 2018 Society of Chemical Industry.


Asunto(s)
Fertilizantes/análisis , Solanum lycopersicum/crecimiento & desarrollo , Agricultura , Productos Agrícolas/química , Productos Agrícolas/crecimiento & desarrollo , Frutas/química , Frutas/crecimiento & desarrollo , Solanum lycopersicum/química , Dióxido de Silicio/análisis , Suelo/química
7.
Astrobiology ; 17(2): 145-153, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28206822

RESUMEN

The lichen Circinaria gyrosa is an astrobiological model defined by its high capacity of resistance to space conditions and to a simulated martian environment. Therefore, it became part of the currently operated BIOMEX experiment on board the International Space Station and the recent STARLIFE campaign to study the effects of four types of space-relevant ionizing radiation. The samples were irradiated with helium and iron ions at doses up to 2 kGy, with X-rays at doses up to 5 kGy and with γ rays at doses from 6 to 113 kGy. Results on C. gyrosa's resistance to simulated space ionizing radiation and its post-irradiation viability were obtained by (i) chlorophyll a fluorescence of photosystem II (PSII), (ii) epifluorescence microscopy, (iii) confocal laser scanning microscopy (CLSM), and (iv) field emission scanning electron microscopy (FESEM). Results of photosynthetic activity and epifluorescence show no significant changes up to a dose of 1 kGy (helium ions), 2 kGy (iron ions), 5 kGy (X-rays)-the maximum doses applied for those radiation qualities-as well as a dose of 6 kGy of γ irradiation, which was the lowest dose applied for this low linear energy transfer (LET) radiation. Significant damage in a dose-related manner was observed only at much higher doses of γ irradiation (up to 113 kGy). These data corroborate the findings of the parallel STARLIFE studies on the effects of ionizing radiation on the lichen Circinaria gyrosa, its isolated photobiont, and the lichen Xanthoria elegans. Key Words: Simulated space ionizing radiation-Gamma rays-Extremotolerance-Lichens-Circinaria gyrosa-Photosynthetic activity. Astrobiology 17, 145-153.


Asunto(s)
Exobiología , Líquenes/efectos de la radiación , Modelos Biológicos , Radiación Ionizante , Clorofila/análisis , Clorofila A , Relación Dosis-Respuesta en la Radiación , Líquenes/metabolismo , Líquenes/ultraestructura , Microscopía Fluorescente , Fotosíntesis/efectos de la radiación , Complejo de Proteína del Fotosistema II/metabolismo , Espectrometría por Rayos X
8.
Astrobiology ; 17(2): 154-162, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28206823

RESUMEN

Lichen symbioses between fungi and algae represent successful life strategies to colonize the most extreme terrestrial habitats. Consequently, space exposure and simulation experiments have demonstrated lichens' high capacity for survival, and thus, they have become models in astrobiological research with which to discern the limits and limitations of terrestrial life. In a series of ground-based irradiation experiments, the STARLIFE campaign investigated the resistance of astrobiological model organisms to galactic cosmic radiation, which is one of the lethal stressors of extraterrestrial environments. Since previous studies have identified that the alga is the more sensitive lichen symbiont, we chose the isolated photobiont Trebouxia sp. of the astrobiological model Circinaria gyrosa as a subject in the campaign. Therein, γ radiation was used to exemplify the deleterious effects of low linear energy transfer (LET) ionizing radiation at extremely high doses up to 113 kGy in the context of astrobiology. The effects were analyzed by chlorophyll a fluorescence of photosystem II (PSII), cultivation assays, live/dead staining and confocal laser scanning microscopy (CLSM), and Raman laser spectroscopy (RLS). The results demonstrate dose-dependent impairment of photosynthesis, the cessation of cell proliferation, cellular damage, a decrease in metabolic activity, and degradation of photosynthetic pigments. While previous investigations on other extraterrestrial stressors have demonstrated a high potential of resistance, results of this study reveal the limits of photobiont resistance to ionizing radiation and characterize γ radiation-induced damages. This study also supports parallel STARLIFE studies on the lichens Circinaria gyrosa and Xanthoria elegans, both of which harbor a Trebouxia sp. photobiont. Key Words: Astrobiology-Gamma rays-Extremotolerance-Ionizing radiation-Lichens-Photobiont. Astrobiology 17, 154-162.


Asunto(s)
Exobiología , Líquenes/efectos de la radiación , Modelos Biológicos , Radiación Ionizante , Clorofila/análisis , Clorofila A , Relación Dosis-Respuesta en la Radiación , Fluorescencia , Rayos Láser , Líquenes/crecimiento & desarrollo , Líquenes/metabolismo , Fotosíntesis/efectos de la radiación , Espectrometría Raman
9.
Orig Life Evol Biosph ; 47(2): 187-202, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27033201

RESUMEN

The search for traces of extinct or extant life in extraterrestrial environments is one of the main goals for astrobiologists; due to their ability to withstand stress producing conditions, extremophiles are perfect candidates for astrobiological studies. The BIOMEX project aims to test the ability of biomolecules and cell components to preserve their stability under space and Mars-like conditions, while at the same time investigating the survival capability of microorganisms. The experiment has been launched into space and is being exposed on the EXPOSE-R2 payload, outside of the International Space Station (ISS) over a time-span of 1.5 years. Along with a number of other extremophilic microorganisms, the Antarctic cryptoendolithic black fungus Cryomyces antarcticus CCFEE 515 has been included in the experiment. Before launch, dried colonies grown on Lunar and Martian regolith analogues were exposed to vacuum, irradiation and temperature cycles in ground based experiments (EVT1 and EVT2). Cultural and molecular tests revealed that the fungus survived on rock analogues under space and simulated Martian conditions, showing only slight ultra-structural and molecular damage.


Asunto(s)
Ascomicetos , Regiones Antárticas , Exobiología , Medio Ambiente Extraterrestre , Rayos Ultravioleta
10.
Am J Perinatol ; 33(12): 1115-20, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27367281

RESUMEN

Objective Our study aims were to establish whether subjects enrolled in current obstetric clinical trials proportionately reflects the contemporary representation of Hispanic ethnicities and their birth rates in the United States. Methods Using comprehensive source data over a defined interval (January 2011-September 2015) on birth rates by ethnicity from the Centers for Disease Control and Prevention (CDC), we evaluated the proportional rate by ethnicity, then analyzed the observed to expected relative ratio of enrolled subjects. Results Hispanic women comprise a significant contribution to births in the United States (23% of all births). Systematic analysis of 90 published obstetric clinical trials showed a correlation between inclusion of Hispanic gravidae and the corresponding state's birth rates (r = 0.501, p < 0.001). While the mean was strongly correlated, individual clinical trials may have relatively over-enrolled (n = 31, or 34%) or under-enrolled (n = 33, or 37%) relative to their regional population. In 48% of obstetric clinical trials the Hispanic proportion of the study population was not reported. Conclusion Hispanic gravidae represent a significant number of contemporary U.S. births, and are generally adequately represented as obstetric subjects in clinical trials. However, this is trial-dependent, with significant trial-specific under- and over-enrollment of Hispanic subjects relative to the regional birth population.


Asunto(s)
Tasa de Natalidad/etnología , Ensayos Clínicos como Asunto/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos , Obstetricia , Selección de Paciente , Femenino , Número de Embarazos , Humanos , Población , Embarazo , Estados Unidos
11.
Astrobiology ; 15(12): 1052-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26684504

RESUMEN

UNLABELLED: Dehydrated Antarctic cryptoendolithic communities and colonies of the rock inhabitant black fungi Cryomyces antarcticus (CCFEE 515) and Cryomyces minteri (CCFEE 5187) were exposed as part of the Lichens and Fungi Experiment (LIFE) for 18 months in the European Space Agency's EXPOSE-E facility to simulated martian conditions aboard the International Space Station (ISS). Upon sample retrieval, survival was proved by testing colony-forming ability, and viability of cells (as integrity of cell membrane) was determined by the propidium monoazide (PMA) assay coupled with quantitative PCR tests. Although less than 10% of the samples exposed to simulated martian conditions were able to proliferate and form colonies, the PMA assay indicated that more than 60% of the cells and rock communities had remained intact after the "Mars exposure." Furthermore, a high stability of the DNA in the cells was demonstrated. The results contribute to assessing the stability of resistant microorganisms and biosignatures on the surface of Mars, data that are valuable information for further search-for-life experiments on Mars. KEY WORDS: Endoliths-Eukaryotes-Extremophilic microorganisms-Mars-Radiation resistance.


Asunto(s)
Ascomicetos , ADN de Hongos/análisis , Medio Ambiente Extraterrestre , Marte , Viabilidad Microbiana , Regiones Antárticas , Ascomicetos/genética , Atmósfera , Recuento de Colonia Microbiana , Vuelo Espacial , Simulación del Espacio , Nave Espacial
12.
Astrobiology ; 12(5): 508-16, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22680696

RESUMEN

Cryptoendolithic microbial communities and epilithic lichens have been considered as appropriate candidates for the scenario of lithopanspermia, which proposes a natural interplanetary exchange of organisms by means of rocks that have been impact ejected from their planet of origin. So far, the hardiness of these terrestrial organisms in the severe and hostile conditions of space has not been tested over extended periods of time. A first long-term (1.5 years) exposure experiment in space was performed with a variety of rock-colonizing eukaryotic organisms at the International Space Station on board the European EXPOSE-E facility. Organisms were selected that are especially adapted to cope with the environmental extremes of their natural habitats. It was found that some-but not all-of those most robust microbial communities from extremely hostile regions on Earth are also partially resistant to the even more hostile environment of outer space, including high vacuum, temperature fluctuation, the full spectrum of extraterrestrial solar electromagnetic radiation, and cosmic ionizing radiation. Although the reported experimental period of 1.5 years in space is not comparable with the time spans of thousands or millions of years believed to be required for lithopanspermia, our data provide first evidence of the differential hardiness of cryptoendolithic communities in space.


Asunto(s)
Radiación Electromagnética , Medio Ambiente Extraterrestre , Vuelo Espacial , Exobiología/métodos , Líquenes/fisiología , Viabilidad Microbiana/efectos de la radiación , Temperatura
13.
Appl Environ Microbiol ; 76(7): 2115-21, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20154120

RESUMEN

Many cyanobacteria are known to tolerate environmental extremes. Motivated by an interest in selecting cyanobacteria for applications in space, we launched rocks from a limestone cliff in Beer, Devon, United Kingdom, containing an epilithic and endolithic rock-dwelling community of cyanobacteria into low Earth orbit (LEO) at a height of approximately 300 kilometers. The community was exposed for 10 days to isolate cyanobacteria that can survive exposure to the extreme radiation and desiccating conditions associated with space. Culture-independent (16S rRNA) and culture-dependent methods showed that the cyanobacterial community was composed of Pleurocapsales, Oscillatoriales, and Chroococcales. A single cyanobacterium, a previously uncharacterized extremophile, was isolated after exposure to LEO. We were able to isolate the cyanobacterium from the limestone cliff after exposing the rock-dwelling community to desiccation and vacuum (0.7 x 10(-3) kPa) in the laboratory. The ability of the organism to survive the conditions in space may be linked to the formation of dense colonies. These experiments show how extreme environmental conditions, including space, can be used to select for novel microorganisms. Furthermore, it improves our knowledge of environmental tolerances of extremophilic rock-dwelling cyanobacteria.


Asunto(s)
Carbonato de Calcio , Cianobacterias/aislamiento & purificación , Cianobacterias/efectos de la radiación , Desecación , Análisis por Conglomerados , Cianobacterias/clasificación , Cianobacterias/genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Medio Ambiente Extraterrestre , Metagenoma , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Reino Unido
14.
Orig Life Evol Biosph ; 39(6): 565-79, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19387863

RESUMEN

Cyanobacteria are photosynthetic organisms that have been considered for space applications, such as oxygen production in bioregenerative life support systems, and can be used as a model organism for understanding microbial survival in space. Akinetes are resting-state cells of cyanobacteria that are produced by certain genera of heterocystous cyanobacteria to survive extreme environmental conditions. Although they are similar in nature to endospores, there have been no investigations into the survival of akinetes in extraterrestrial environments. The aim of this work was to examine the survival of akinetes from Anabaena cylindrica in simulated extraterrestrial conditions and in Low Earth Orbit (LEO). Akinetes were dried onto limestone rocks and sent into LEO for 10 days on the ESA Biopan VI. In ground-based experiments, the rocks were exposed to periods of desiccation, vacuum (0.7×10(-3) kPa), temperature extremes (-80 to 80°C), Mars conditions (-27°C, 0.8 kPa, CO(2)) and UV radiation (325-400 nm). A proportion of the akinete population was able to survive a period of 10 days in LEO and 28 days in Mars simulated conditions, when the rocks were not subjected to UV radiation. Furthermore, the akinetes were able to survive 28 days of exposure to desiccation and low temperature with high viability remaining. Yet long periods of vacuum and high temperature were lethal to the akinetes. This work shows that akinetes are extreme-tolerating states of cyanobacteria that have a practical use in space applications and yield new insight into the survival of microbial resting-state cells in space conditions.


Asunto(s)
Viabilidad Microbiana , Esporas Bacterianas/fisiología , Anabaena cylindrica/fisiología , Frío , Desecación , Medio Ambiente Extraterrestre , Calor , Nave Espacial , Rayos Ultravioleta , Vacio
15.
Astrobiology ; 7(3): 443-54, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17630840

RESUMEN

This experiment was aimed at establishing, for the first time, the survival capability of lichens exposed to space conditions. In particular, the damaging effect of various wavelengths of extraterrestrial solar UV radiation was studied. The lichens used were the bipolar species Rhizocarpon geographicum and Xanthoria elegans, which were collected above 2000 m in the mountains of central Spain and as endolithic communities inhabiting granites in the Antarctic Dry Valleys. Lichens were exposed to space in the BIOPAN-5 facility of the European Space Agency; BIOPAN-5 is located on the outer shell of the Earth-orbiting FOTON-M2 Russian satellite. The lichen samples were launched from Baikonur by a Soyuz rocket on May 31, 2005, and were returned to Earth after 16 days in space, at which time they were tested for survival. Chlorophyll fluorescence was used for the measurement of photosynthetic parameters. Scanning electron microscopy in back-scattered mode, low temperature scanning electron microscopy, and transmission electron microscopy were used to study the organization and composition of both symbionts. Confocal laser scanning microscopy, in combination with the use of specific fluorescent probes, allowed for the assessment of the physiological state of the cells. All exposed lichens, regardless of the optical filters used, showed nearly the same photosynthetic activity after the flight as measured before the flight. Likewise, the multimicroscopy approach revealed no detectable ultrastructural changes in most of the algal and fungal cells of the lichen thalli, though a greater proportion of cells in the flight samples had compromised membranes, as revealed by the LIVE/DEAD BacLight Bacterial Viability Kit. These findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms. The lichen upper cortex seems to provide adequate protection against solar radiation. Moreover, after extreme dehydration induced by high vacuum, the lichens proved to be able to recover, in full, their metabolic activity within 24 hours.


Asunto(s)
Medio Ambiente Extraterrestre , Líquenes , Exobiología , Líquenes/metabolismo , Líquenes/efectos de la radiación , Líquenes/ultraestructura , Microscopía Confocal , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Complejo de Proteína del Fotosistema II/metabolismo , Vuelo Espacial , Rayos Ultravioleta/efectos adversos
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