RESUMEN
Most of the current commercial production of glacial acetic acid (GAA) is by petrochemical routes, primarily methanol carbonylation. GAA is an intermediate in the production of plastics, textiles, dyes, and paints. GAA production from biomass might be an economically viable and sustainable alternative to petroleum-derived routes. Separation of acetic acid from water is a major expense and requires considerable energy. This study evaluates and compares the technical and economic feasibility of GAA production via bioconversion using either ethyl acetate or alamine in diisobutylkerosene (DIBK) as organic solvents for purification. Models of a GAA biorefinery with a production of 120,650 tons/year were simulated in Aspen software. This biorefinery follows the path of pretreatment, enzymatic hydrolysis, acetogen fermentation, and acid purification. Estimated capital costs for different scenarios ranged from USD 186 to 245 million. Recovery of GGA using alamine/DIBK was a more economical process and consumed 64% less energy, due to lower steam demand in the recovery distillation columns. The estimated average minimum selling prices of GGA were USD 756 and 877/ton for alamine/DIBK and ethyl acetate scenarios, respectively. This work establishes a feasible and sustainable approach to produce GGA from poplar biomass via fermentation.
Asunto(s)
Ácido Acético/metabolismo , Biomasa , Costos y Análisis de Costo , Populus/metabolismo , Ácido Acético/aislamiento & purificación , BiotransformaciónRESUMEN
KEY MESSAGE: The early flowering system HSP::AtFT allowed a fast evaluation of a gene containment system based on the construct PsEND1::barnase-barstar for poplar. Transgenic lines showed disturbed pollen development and sterility. Vertical gene transfer through pollen flow from transgenic or non-native plant species into their crossable natural relatives is a major concern. Gene containment approaches have been proposed to reduce or even avoid gene flow among tree species. However, evaluation of genetic containment strategies for trees is very difficult due to the long-generation times. Early flowering induction would allow faster evaluation of genetic containment in this case. Although no reliable methods were available for the induction of fertile flowers in poplar, recently, a new early flowering approach was developed. In this study, early flowering poplar lines containing the gene construct PsEND1::barnase-barstar were obtained. The PsEND1 promoter was chosen due to its early expression pattern, its versality and efficiency for generation of male-sterile plants fused to the barnase gene. RT-PCRs confirmed barnase gene activity in flowers, and pollen development was disturbed, leading to sterile flowers. The system developed in this study represents a valuable tool for gene containment studies in forest tree species.
Asunto(s)
Proteínas Bacterianas/genética , Flores/crecimiento & desarrollo , Edición Génica/métodos , Infertilidad Vegetal/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Polen/crecimiento & desarrollo , Populus/crecimiento & desarrollo , Ribonucleasas/genética , Proteínas de Arabidopsis/genética , Proteínas Bacterianas/metabolismo , Flores/genética , Flores/metabolismo , Flores/efectos de la radiación , Regulación de la Expresión Génica de las Plantas , Flujo Génico , Vectores Genéticos , Respuesta al Choque Térmico , Plantas Modificadas Genéticamente/metabolismo , Plantas Modificadas Genéticamente/efectos de la radiación , Polen/genética , Populus/genética , Populus/metabolismo , Populus/efectos de la radiación , Regiones Promotoras Genéticas , Ribonucleasas/metabolismo , Temperatura , Transformación GenéticaRESUMEN
The adaptation of crops to acid soils is needed for the maintenance of food security in a sustainable way, as decreasing fertilizers use and mechanical interventions in the soil would favor the reduction of agricultural practices' environmental impact. Phosphate deficiency and the presence of reactive aluminum affect vital processes to the plant in this soil, mostly water and nutrient absorption. From this, the understanding of the molecular response to these stresses can foster strategies for genetic improvement, so the aim was to broadly analyze the transcriptional variations in Poupulus spp. in response to these abiotic stresses, as a plant model for woody crops. A co-expression network was constructed among 3,180 genes differentially expressed in aluminum-stressed plants with 34,988 connections. Of this total, 344 genes presented two-fold transcriptional variation and the group of genes associated with those regulated after 246 hours of stress had higher number of connections per gene, with some already characterized genes related to this stress as main hubs. Another co-expression network was made up of 8,380 connections between 550 genes regulated by aluminum stress and phosphate deficiency, in which 380 genes had similar profile in both stresses and only eight with transcriptional variation higher than 20%. All the transcriptomic data are presented here with functional enrichment and homology comparisons with already characterized genes in another species that are related to the explored stresses, in order to provide a broad analysis of the co-opted responses for both the stresses as well as some specificity. This approach improves our understanding regarding the plants adaptation to acid soils and may contribute to strategies of crop genetic improvement for this condition that is widely present in regions of high agricultural activity.
Asunto(s)
Aluminio/toxicidad , Fosfatos/metabolismo , Populus/genética , Estrés Fisiológico/genética , Adaptación Fisiológica/genética , Productos Agrícolas , Fertilizantes/toxicidad , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Humanos , Populus/efectos de los fármacos , Populus/metabolismo , Suelo/química , Inanición/genética , Transcriptoma/efectos de los fármacos , Transcriptoma/genéticaRESUMEN
Rust is one of the most important biotic stress factors that affect poplars. The aims of this work were: (i) to analyze the changes in growth and nitrogen (N) accumulation in Populus deltoides W. Bartram ex Marshall plants infected with rust (Melampsora medusae Thümen.) and to determine how internal N stores are affected by the disease, in plants growing under two N availabilities in the soil; and (ii) to evaluate the impact of rust in the early sprout in the following growing season and the cumulative effect of the disease after repeated infections. Two clones with different susceptibility to rust were analyzed. At leaf level, rust reduced gas exchange capacity, water conductance in liquid phase and photosynthetic rate in both clones. At plant level, rust reduced plant growth, accelerated leaf senescence and abscission occurred with a higher concentration of leaf N. Even though N concentration in stems and roots were not significantly reduced by rust, total N accumulation in perennial tissues was reduced in infected plants. The vigor of the early sprout of plants infected by rust in the previous season was lower than that of non-infected plants. Therefore, rust affects plant growth by reducing the photosynthetic capacity and leaf area duration, and by decreasing internal nutrient recycling. As nutrient reserves in perennial tissues are lower, rust infection reduces not only the growth of the current season, but also has a cumulative effect on the following years. The reduction of growth was similar in both clones. High availability of N in the soil had no effect on leaf physiology but increased plant growth, delayed leaf senescence and abscission, and increased total N accumulation. If fertilization increases plant growth (stem and root dry mass) it can mitigate the negative effect of the pathogen in the reduction of nutrient storages and future growth.
Asunto(s)
Basidiomycota , Nitrógeno/metabolismo , Enfermedades de las Plantas , Populus/metabolismo , Árboles/metabolismo , Enfermedades de las Plantas/microbiología , Populus/crecimiento & desarrollo , Populus/microbiología , Estaciones del Año , Suelo/química , Árboles/crecimiento & desarrollo , Árboles/microbiologíaRESUMEN
Solid-state fermentation (SSF) with the medicinal higher Basidiomycete Ganoderma lucidum was studied as a strategy to use pine (Pinus radiata D. Don) and poplar (Populus nigra L.) wood chips and sawdust. Fruiting bodies were produced and the value of the biotransformed substrate was assessed. The highest mushroom yield (63 g dry weight per kilogram of dry substrate) was obtained with poplar sawdust and wood chips. Immersion of the bioreactors was a simple watering method that obtained suitable yields. Two morphological types were induced using 2 different incandescent light intensities. High light irradiation induced the highest valued mushroom morphology (as a whole product). Time course study of substrate biodegradation and mycelial growth dynamics indicated that the trophophase lasted 20 days and presented laccase activity of 0.01-0.03 units · g-1. The activity at idiophase was 10 times higher. Aqueous and alkali extracts, as well as carbohydrase enzyme profile activity, revealed differences in the properties of the residual substrate; some related to the substrate source are considered to be of concern for further use of this pretreated biomass. In view of the results obtained, we propose use of SSF of pine and poplar with G. lucidum to profitably recycle softwood by-products from the timber industry.
Asunto(s)
Cuerpos Fructíferos de los Hongos/metabolismo , Reishi/química , Reishi/metabolismo , Madera/metabolismo , Argentina , Biomasa , Reactores Biológicos/microbiología , Fermentación , Lacasa/análisis , Luz , Lignina/metabolismo , Morfogénesis , Micelio/crecimiento & desarrollo , Micelio/metabolismo , Pinus/metabolismo , Populus/metabolismo , Reishi/efectos de la radiaciónRESUMEN
The survival of all vascular plants depends on phloem and xylem, which comprise a hydraulically coupled tissue system that transports photosynthates, water, and a variety of other molecules and ions. Although xylem hydraulics has been extensively studied, until recently, comparatively little is known quantitatively about the phloem hydraulic network and how it is functionally coupled to the xylem network, particularly in photosynthetic leaves. Here, we summarize recent advances in quantifying phloem hydraulics in fully expanded mature leaves with different vascular architectures and show that (1) the size of phloem conducting cells across phylogenetically different taxa scales isometrically with respect to xylem conducting cell size, (2) cell transport areas and lengths increase along phloem transport pathways in a manner that can be used to model Münch's pressure-flow hypothesis, and (3) report observations that invalidate da Vinci's and Murray's hydraulic models as plausible constructs for understanding photosynthate transport in the leaf lamina.
Asunto(s)
Floema/metabolismo , Plantas/anatomía & histología , Transporte Biológico , Ginkgo biloba/anatomía & histología , Ginkgo biloba/metabolismo , Floema/anatomía & histología , Fotosíntesis , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Tallos de la Planta/anatomía & histología , Tallos de la Planta/metabolismo , Plantas/metabolismo , Populus/anatomía & histología , Populus/metabolismo , Xilema/anatomía & histología , Xilema/metabolismoAsunto(s)
Interacciones Huésped-Patógeno , Populus/microbiología , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Glutatión/metabolismo , Calor , Oxidación-Reducción , Fotofosforilación , Hojas de la Planta/metabolismo , Populus/genética , Populus/metabolismo , Pseudomonas syringae/fisiología , Ácido Salicílico/metabolismo , Transducción de Señal/fisiologíaRESUMEN
A pollution gradient was observed in tree foliage sampled in the vicinity of a large aluminium production facility in Patagonia (Argentina). Leaves of Eucalyptus rostrata, and Populus hybridus and different needle ages of Pinus spec. were collected and concentrations of aluminium (Al) and sulphur (S) as well as physiological parameters (chlorophyll and lipid oxidation products) were analyzed. Al and S concentrations indicate a steep pollution gradient in the study showing a relationship with the physiological parameters in particular membrane lipid oxidation products. The present study confirms that aluminium smelting results in high Al and sulphur deposition in the study area, and therefore further studies should be carried out taking into account potentially adverse effects of these compounds on human and ecosystem health.