12 research outputs found
Greenhouse Gases Production from Some Crops Growing Under Greenhouse Conditions
Greenhouse gases, such as carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4), play an important role in global climate change. For example, CO2 production occurs as a result of the seasonal cycles of the biotic processes of photosynthesis and respiration, as well as through anthropogenic activities and abiotic processes such as the burning of fossil fuels. Many activities, such as Agribusiness (the production of crops and animals for food) create greenhouse gases. Our research group has studied several soil treatments such as wastewater, wastewater sludge, vermicomposting, and urea among others, in order to study the effects of soil treatments on the production of greenhouse gases (CO2, N2O, and CH4) in several cultivars, but mainly in maize, sunflower and the common bean. The principal aim of this chapter is to show how these greenhouse gases are affected by the type of treatment, the properties of the soil, and the cultivar in question. We also look at which processes are involved in the production of CO2, N2O, and CH4 from cultivated soil. We present a review of several experiments carried out under in vitro or greenhouse conditions
Bioactive compounds, antioxidant and antimicrobial activity of propolis extracts during In vitro digestion
The objective of this research was to determine the content of total phenols, total flavonoids, and the antioxidant and antimicrobial activity of the ethanolic extracts of propolis obtained by two methodologies during in vitro digestion. Ethanolic extracts of propolis were obtained by ultrasound and maceration and the yield and content of the bioactive compounds, as well as their antimicrobial and antioxidant activity, were evaluated. Yields higher than those reported in other investigations (71.6%) were obtained. The highest content of phenols and flavonoids in the ethanolic extracts was 34,406.6 mg GAE/100 g in propolis from San Pedro, obtained by maceration (SP M), and 19,523.2 mg QE/100 g in propolis from Teotitlán, obtained by ultrasound (TU), respectively, being higher than what is established in Mexican regulations. The antioxidant and antimicrobial activity of the extracts was not affected by the method of obtaining. At the end of the in vitro digestion there was an 80% loss of the phenolic content and a 90% loss of the flavonoid content. Therefore, antioxidant activity was affected. On the other hand, ultrasound improves the obtaining of bioactive compounds. In vitro digestion decreases the content of bioactive compounds; therefore, their functional properties are affected. Thus, it is important to consider technologies that allow extracts to be protected from in vitro digestion conditions.info:eu-repo/semantics/publishedVersio
Suitability assessment for electricity generation through renewable sources: towards sustainable energy production
Power generation through renewable sources is an effective alternative to mitigate climate change as its environmental impact is lower compared to fossil fuels. However, socio-economic problems are constant in sites where power plants are installed, especially in developing countries. In this paper, an innovative methodology was developed to assess the suitability of electricity generation through solar, wind, and biomass energy. Unlike most studies found in scientific literature, this work considers social, environmental, and economic aspects as key to determine the suitability of energy projects. First, we carried out a comprehensive analysis on social acceptance and resilience towards renewable energy and the conditions for communities to benefit from these projects; then, we analyzed the availability and capacity of renewable energy sources in Mexico, as a case study. Next, a set of indicators related to the three pillars of sustainability was developed to assess the conditions of each place with the best renewable resources in the country. The life cycle and capacity factor of each technology were also considered. Lastly, a mathematical model was developed to determine the most suitable locations and technologies for power generation. The results show a trend towards the states of northern Mexico, especially those bordering the United States, as the most viable for electricity generation. The most appropriate technology is wind energy. Finally, Oaxaca, the state with the best wind resources and current leader in wind power generation in Mexico is, by contrast, the least viable state for wind generation, as has been later confirmed by scientific evidence, as wind facilities are associated with severe socio-cultural and economic damage in host communities in this state.La generación eléctrica mediante fuentes renovables es una alternativa eficaz para mitigar el cambio climático, pues su impacto ambiental es menor en comparación al de los combustibles fósiles. Sin embargo, hay problemas socioeconómicos constantes en los lugares donde se instalan las centrales eléctricas, especialmente en los países en desarrollo. En este trabajo, se desarrolló una metodología innovadora para evaluar la idoneidad de la generación de electricidad a través de energía solar, eólica y biomasa. A diferencia de la mayoría de los estudios encontrados en la literatura científica, este trabajo considera los aspectos sociales, ambientales y económicos como claves para determinar la idoneidad de los proyectos energéticos. Primero, se llevó a cabo un análisis sobre la aceptación social y la resiliencia hacia las energías renovables y las condiciones para que las comunidades se beneficien de estos proyectos, después, analizamos la disponibilidad y capacidad de las fuentes de energía renovable en México, como caso de estudio. A continuación, se desarrolló un conjunto de indicadores relacionados con los tres pilares de la sustentabilidad, para evaluar las condiciones de cada lugar con los mejores recursos renovables del país. También se consideró el ciclo de vida y el factor de capacidad de cada tecnología. Por último, se desarrolló un modelo matemático para conocer los lugares y tecnologías más adecuados para la generación eléctrica. Los resultados muestran una tendencia hacia los estados del norte de México, especialmente los limítrofes con Estados Unidos, a ser los más viables para la generación eléctrica. La tecnología más adecuada es la energía eólica. Finalmente, los hallazgos también indican que Oaxaca, el estado con los mejores recursos eólicos y líder en generación mediante esta tecnología en México, es el estado menos viable para la generación eólica, como fue confirmado con evidencia científica, ya que las instalaciones eólicas están asociadas con daños culturales y económicos en las comunidades receptoras en este estado
Silver and Hematite Nanoparticles Had a Limited Effect on the Bacterial Community Structure in Soil Cultivated with <i>Phaseolus vulgaris</i> L.
The amount of nanoparticles that enters the environment has increased substantially in the last years. How they might affect plant characteristics and the bacterial community structure when they enter the soil, however, is still debated, as there is a continuous interaction between them. In this study, we determined the effect of silver (Ag-NPs) and hematite (α-Fe2O3-NPs) nanoparticles (0.15 g kg−1) on the characteristics of common bean (Phaseolus vulgaris L.) and the rhizosphere, non-rhizosphere and uncultivated soil bacterial community. The application of Ag-NPs or α-Fe2O3-NPs did not affect plant growth, but changed the amount of some heavy metals in the roots and aerial parts. The application of nanoparticles had a limited effect on the diversity, structure and functional profile of the soil and rhizosphere bacterial communities, but they were altered by cultivation of the bean plants and changed over time. It was found that application of Ag-NPs or α-Fe2O3-NPs had no effect on bean plant growth and only a small effect on the bacterial community structure and its putative metabolic functions. These findings show that in a complex system, such as a soil, different factors might affect the bacterial community structure and alter the possible effect of nanoparticles on it
Bioactive Compounds of Opuntia spp. Acid Fruits: Micro and Nano-Emulsified Extracts and Applications in Nutraceutical Foods
The acid fruit of the "xoconostle" cactus belongs to the genus Opuntia family of cacti. It is used as a functional food for its bioactive compounds. Several studies reported that xoconostle fruits have a high amount of ascorbic acid, betalains, phenols, tannins, and flavonoids. These compounds confer antioxidant, antibacterial, anti-inflammatory, and hepatoprotective gastroprotective activity. Xoconostle fruit extracts were tested by in vitro assays where the digestion conditions were simulated to measure their stability. At the same time, the extracts were protected by encapsulation (microencapsulation, multiple emulsions, and nanoemulsions). Applications of encapsulated extracts were probed in various food matrices (edible films, meat products, dairy, and fruit coatings). The xoconostle is a natural source of nutraceutical compounds, and the use of this fruit in the new food could help improve consumers’ health
Inhibition of Urease, Elastase, and β-Glucuronidase Enzymatic Activity by Applying Aqueous Extracts of Opuntia oligacantha C.F. Först Acid Fruits: In Vitro Essay under Simulated Digestive Conditions
Non-communicable diseases such as gastric inflammatory diseases and the hepatic pathologies are mainly related to bad lifestyle habits such as recurrent consumption of non-steroidal anti-inflammatory drugs (NSAIDs), excessive intake of alcohol, tobacco, steroids (high doses), alkaline agents, strong acid foods, and high-fat food, and Helicobacter pylori infections, among others. The fruit of Opuntia oligacantha C.F. Först var. Ulapa (xoconostle) is currently being studied due its nutritional and functional properties. The objective of the present study was to evaluate gastroprotective, anti-inflammatory, and hepatoprotective activities of different parts of xoconostle fruit by establishing in vitro simulated gastrointestinal conditions. Four treatments were established to test aqueous extracts (pericarp (P), mesocarp (M), endocarp (E) and whole fruit (W)). The quantified bioactive compounds were the total phenols, flavonoids, tannins, and betalains. The enzymatic assays were: urease, elastase, and β-glucuronidase. Significant differences (p < 0.05) of bioactive compounds content were measured in xoconostle extracts, the highest concentration was found in W (phenols 313 mg GAE/100 g, flavonoids 189 mg QE/100 g, tannins 71 mg CATE/100 g). The betalains content was higher in E; 17 mg/100 g significant differences were observed (p < 0.05) in the enzymatic inhibitions test (urease, elastase and β-glucuronidase), where W presented the highest inhibition activity (86%, 79%, and 84%), respectively. Bioactive compounds after in vitro gastrointestinal tests were maintained above 60% enzymatic inhibition activity
Production of Kojic Acid by <i>Aspergillus niger</i> M4 with Different Concentrations of Yeast Extract as a Nitrogen Source
In agro-industrial processes, microorganisms that are not pathogenic and that generate molecules are generally recognized as safe (GRAS). The Aspergillus niger fungus has different industrial applications, being used to produce citric acid and 166 other secondary metabolites. The objective of this research was to optimize a culture medium to induce the production of kojic acid (KA) by the Aspergillus niger M4 strain in a liquid fermentation process. Four fermentative kinetics were developed in flasks, using different levels of yeast extract in (1) 0.05 g/L, (2) 0.10 g/L, (3) 2.5 g/L, and (4) 2.5 g/L + Zinc sulfate. The culture medium conditions influenced the formation and speed of biomass and the synthesis and yield of KA. The optimum production points were from 72 h and 96 h with 0.552 g/L and 0.510 g/L of KA using 2.5 g/L of yeast extract and with a pH of 5.5. The Aspergillus niger M4 strain had the ability to produce kojic acid, which was induced by the concentration of the nitrogen source
Nutritional Parameters, Biomass Production, and Antioxidant Activity of <i>Festuca arundinacea Schreb.</i> Conditioned with Selenium Nanoparticles
Festuca arundinacea Schreb. is a widely used type of forage due to its great ecological breadth and adaptability. An agricultural intervention that improves the selenium content in cultivated plants has been defined as bio-fortification, a complementary strategy to improve human and non-human animals’ nutrition. The advancement of science has led to an increased number of studies based on nanotechnologies, such as the development of nanoparticles (NPs) and their application in crop plants. Studies show that NPs have different physicochemical properties compared to bulk materials. The objectives of this study were (1) to determine the behavior of F. arundinacea Schreb. plants cultivated with Se nanoparticles, (2) to identify the specific behavior of the agronomic and productive variables of the F. arundinacea Schreb. plants, and (3) to quantify the production and quality of the forage produced from the plant (the bioactive compounds’ concentrations, antioxidant activity, and the concentration of selenium). Three different treatments of SeNPs were established (0, 1.5, 3.0, and 4.5 mg/mL). The effects of a foliar fertilization with SeNPs on the morphological parameters such as the root size, plant height, and biomass production were recorded, as well as the effects on the physicochemical parameters such as the crude protein (CP), lipids (L), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), carbohydrates (CH), the content of total phenols, total flavonoids, tannins, quantification of selenium and antioxidant activity 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH). Significant differences (p F. arundinacea Schreb. plants fertilized with 4.5 mg/L had selenium contents of 0.3215, 0.3191, and 0.3218 mg/Kg MS; total phenols of 249.56, 280.02, and 274 mg EAG/100 g DM; and total flavonoids of 63.56, 64.96, and 61.16 mg QE/100 g DM. The foliar biofortified treatment with a concentration of 4.5 mg/mL Se NPs had the highest antioxidant capacities (284.26, 278.35, and 289.96 mg/AAE/100 g)
Influence of Bioactive Compounds Incorporated in a Nanoemulsion as Coating on Avocado Fruits (Persea americana) during Postharvest Storage: Antioxidant Activity, Physicochemical Changes and Structural Evaluation
The objective of the present study was to determine the effect of the application of a nanoemulsion made of orange essential oil and Opuntia oligacantha extract on avocado quality during postharvest. The nanoemulsion was applied as a coating in whole fruits, and the following treatments were assessed: concentrated nanoemulsion (CN), 50% nanoemulsion (N50), 25% nanoemulsion (N25) and control (C). Weight loss, firmness, polyphenol oxidase (PPO) activity, total soluble solids, pH, external and internal colour, total phenols, total flavonoids, antioxidant activity by 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), while the structural evaluation of the epicarp was assessed through histological cuts. Significant differences were found (p < 0.05) among the treatments in all the response variables. The best results were with the N50 and N25 treatments for firmness and weight loss, finding that the activity of the PPO was diminished, and a delay in the darkening was observed in the coated fruits. Furthermore, the nanoemulsion treatments maintained the total phenol and total flavonoid contents and potentiated antioxidant activity at 60 days. This histological study showed that the nanoemulsion has a delaying effect on the maturation of the epicarp. The results indicate that using this nanoemulsion as a coating is an effective alternative to improve the postharvest life of avocado
TiO2 nanoparticles affect the bacterial community structure and Eisenia fetida (Savigny, 1826) in an arable soil
The amount of nanoparticles (NP), such as TiO2, has increased substantially in the environment. It is still largely unknown, however, how NP might interact with earthworms and organic material and how this might affect the bacterial community structure and their functionality. Therefore, an arable soil was amended with TiO2 NP at 0, 150 or 300 mg kg−1 and subjected to different treatments. Treatments were soil amended with ten earthworms (Eisenia fetida (Savigny, 1826)) with fully developed clitellum and an average fresh mass of 0.5 to 500 g dry soil, 1.75 g tyndallized Quaker® oat seeds Avena sativa (L.) kg−1, or earthworms plus oat seeds, or left unamended. The bacterial community structure was monitored throughout the incubation period. The bacterial community in the unamended soil changed over time and application of oats, earthworm and a combination of both even further, with the largest change found in the latter. Application of NP to the unamended soil and the earthworm-amended soil altered the bacterial community, but combining it by adding oats negated that effect. It was found that the application of organic material, that is, oats, reduced the effect of the NP applied to soil. However, as the organic material applied was mineralized by the soil microorganisms, the effect of NP increased again over time