- Количество слайдов: 14
Tracking the short-term fate of some organic pollutants of the ISS Crew Latent Condensate (methanol, and isopropanol) when included in the nutrient solution for rocket (Eruca sativa Mill. ) hydroponic cultivation Simona Proietti, Walter Stefanoni, Stefano Moscatello, Emanuele Pallozzi, Lucia Grizzaffi, Ilaria Locantore, Carlo Calfapietra, Marco Lauteri, Alberto Battistelli. CNR – IBAF Istituto di Biologia Agroalimentare e Forestale, Porano (TR) - Italy Thales Alenia Space Italia Torino - Italy DAFNE, Università della Tuscia, via San Camillo De Lellis snc, 01100 Viterbo (VT) - Italy International Project: Inflatable greenhouse for space plant food production and life support. Italian Ministry of Foreign Affairs (MAE) th Review Conference on Scientific and Technological Cooperation Agreement between Italy and USA 10 Workshop on Bioregenerative Life Support Turin, 18 -19 May 2015
During long term human space mission, water recovered from various streams should be used as the basic component of nutrient solutions for plant cultivation. For this end the quality of recovery water needs to be carefully evaluated since plants growth and plant food quality can be affected by the quality of water used 5 x 10 -3 % 8 x 10 -4 % 4 x 10 -4 % Water streams from space station can contains various organic contaminants Methanol, Ethanol, and Iso-propanol (MEI) are included in the list of Wastewater Contaminants in Crew Latent Condensate (Wastewater Contaminants in Crew Latent Condensate: Handford, 2004).
Methanol, Ethanol, and Iso-propanol (MEI) are selected to investigate the effects of relevant contaminants found in the ISS on plant growth and on plant physiology. Rocket plant (Eruca sativa Mill. ) ügrown from seeds in a growth chamber üfor 4 weeks üin a floating system Feeding of MEI were imposed on rocket seeds and on rocket plants
With MEI Do the rocket seeds germinate? Methanol and isopropanol do not affect rocket seeds germination also at high concentration (1%) Ethanol affects seeds germination only at high concentration (1% and 0, 5%) When the ethanol concentration was decreased at 0, 2% until the concentration found in the water condensate of ISS the germination rate of rocket seed is not affected. 8 x 10 -4 % = ethanol found in the water condensate of ISS
With MEI Are there a rapid and destructive effects on rocket plants? Gas exchange measurements and fluorescence of chlorophyll a using a Licor XT 6400 after feeding with 15 m. M of MEI Feeding Alcohols did not affected photosynthesis rate nor fluorescence emission. Gas exchanges were unaltered by alcohols also at higher concentration to respect the concentration found in the water streams of ISS.
Are they taken up and accumulated by rocket plants? MEI Are they accumulated? Are they translocated? Leaf extracts from plants fed with MEI 1% were analyzed by Ion Chromatography ICS 5000 (Dionex Thermo. Fisher) Are they absorbed? Methanol and Ethanol, but not isopropanol, were detected in leaves after feeding, but a low concentration. Standard Expected Isopropanol in leaf Methanol and Ethanol (and also Isopropanol, see later) are taken up by the rocket root and translocated to leaves, but do not accumulate to high concentration.
What is the fate of MEI once they are inside the plant ? CO 2 (complete destruction) Metabolism Metabolites Formaldehyde - Formic acid Acetaldehyde - Acetic acid Acetone MEI in plant tissues Accumulation (low) Re-emission in the atmosphere Accumulation
Labeling experiments were carried out to test if MEI enter into the respiratory metabolism using 13 C enriched MEI Feeding was carried out with a solution (15 m. M) of each alcohols containing a small proportion of 13 C labeled molecules. The presence of 13 C was measured (d 13 C) on CO 2 released by leaf respiration, by IRMS. Controllo 20 0 Metanolo 24 h -20 -40 d 13 C 40 60 40 20 0 -20 -40 Rapp. isotopico Isotopic ratio Controllo Etanolo 24 h 60 d 13 C Isotopic ratio Rapp. isotopico 60 Isopropanol 15 m. M Ethanol 15 m. M Methanol 15 m. M 40 20 0 -20 -40 Rapp. isotopico Isotopic ratio Controllo Isopropanolo 24 h enriched MEI caused a remarkably change in d 13 C in the respiratory CO 2 with a decreasing intensity with increasing alcohol molecular mass. This clearly indicates the uptake of alcoholic compounds from plants and a fast turn-over of labeled methanol and ethanol molecules as soon as they enter on the plant metabolism. M and E can be metabolized to enter respiratory metabolism: plants can contribute to degradation of M and E to CO 2. Feeding of 13 C
Are their metabolic products accumulated in plant tissues? MEI oxidation Formaldehyde Methanol Formic acid CO 2 oxidation Ethanol oxidation Acetaldehyde Acetic acid oxidation Isopropanol Acetone Organic acids, as a product of alcohols metabolism in plants were analyzed by Dionex™ ICS-5000 from leaf extracts from plants fed with MEI.
Accumulation of metabolic products of MEI in rocket leaves. No accumulation of metabolic products of methanol were detected by IC Acetic acid in leaves An increment of acetic acid in leaves was detected after Ethanol feeding.
Are they released, in the atmosphere? Are their metabolic producs released? Methanol Ethanol Isopropanol oxidation Formaldehyde Methanol Formic acid oxidation Ethanol oxidation Acetaldehyde Acetic acid oxidation Isopropanol Acetone The emission in the atmosphere of MEI and relevant metabolites were analyzed on line by Real-time trace gas analyzer solutions based on Proton-transfer-reaction mass spectrometry (PTR-MS - Ionicon). ØMethanol and formaldehyde and formic acid from methanol oxidation ØEthanol and acetaldehyde and acetic acid from ethanol oxidation ØIsopropanol and acetaldehyde and acetone from isopropanol oxidation CO 2
Isopropil alcohol Methanol was emitted by leaves formaldehyde and formic acid was not detected. After ethanol feeding acetaldehyde was the most abundant organic compound emitted trough stomata. PTR-MS showed that Isopropyl alcohol was adsorbed by rocket plants, translocated and re-emitted by rocket leaves. Isopropyl alcohol was also metabolized in acetaldehyde and in acetone reemitted in the atmosphere.
Conclusions • An array of measuring techniques should be used to track the fate of each organic compound when it enters in contact with a plant via the nutrient solution delivery system. • Even similar molecules can have a very different fate when in contact with plants. • Plant metabolism can destroy the pollutant or even produce other equally or even more dangerous molecules and even release them in the atmosphere. • There is no general rule to be applied. Specific interaction plant/pollutant should be tested with reference to the growing conditions. Perspectives An accurate definition of organic pollutants that can enter in a plant growing system in Bioregenerative Life Support system is necessary to ensure : Øplant growing and productive performances. Øfood quality and security. Øthe potential treat of release in the system of the same or derived pollutants.