El interés nacional y mundial en el cannabis se ha incrementado en los últimos años, en razón a sus propiedades medicinales y aplicaciones industriales. Por ello, se han desarrollado múltiples ...técnicas de extracción y producción de derivados; pero es necesario desarrollar nuevas metodologías verdes y más eficientes para la obtención de fitocannabinoides y producción de preparados de cannabis. Los disolventes eutécticos profundos son disolventes verdes, seguros y versátiles para conseguir metabolitos del cannabis. En esta investigación se prepararon diecinueve disolventes eutécticos profundos de baja viscosidad basados en mentol, β-sitosterol y ácidos grasos, que fueron más eficientes para extraer fitocannabinoides por extracción asistida por ultrasonido en comparación con el etanol. El disolvente Mentol:Ácido octanoico 3:1 presentó el mayor rendimiento de extracción (32.42 %), mediante el ultrasonido empleando un diseño factorial 23 con el que se encontraron las siguientes condiciones óptimas: tiempo de 60 minutos, % DES de 100 % y una relación Cannabis: DES 1:20. Este estudio presenta una extracción verde y eficiente de fitocannabinoides de interés industrial, medicinal o cosmético y se convierte en una alternativa a las técnicas convencionales para la preparación de derivados del cannabis; el proceso es novedoso, optimizable y tiene gran potencial para establecer procesos a escala industrial.
Fique is a plant widely produced in Colombia; its fibers are mainly used in the production of packaging, the fique industry produces large amounts of a residue called fiber dust, this residue ...preserves the properties of the fiber, and however it is discarded without any type of use. In this study, a surface modification consisting of the esterification of fique dust was carried out. Alkalinization was performed to eliminate the hemicellulose present in fique dust in order to facilitate the identification of new carbonyl groups in the FTIR. The esterification of the fique dust was carried out using oxalic acid as a couple agent in a green solvent. The modified fique dust was characterized by the use of spectroscopic (FTIR-ATR) and thermal (TGA, TGD) techniques. The results of the spectroscopic analysis revealed the presence of new carbonyl groups at 1731 cm
−1
, indicating that the esterification reaction was successful. The thermal analysis shows the elimination of hemicellulose from the fique dust after the alkaline treatment, in addition, revealed a decrease in the thermal stability of the fique dust with alkaline treatment and an increase in the thermal stability of the esterified fiber. The esterified fique dust shows an improvement in its solubility in DMSO.
Paracetamol (PCT), also known as acetaminophen, is a drug used to treat fever and mild to moderate pain. After consumption by animals and humans, it is excreted through the urine to the sewer ...systems, wastewater treatment plants, and other aquatic/natural environments. It has been detected in trace amounts in effluents of wastewater plant treatments, sewage sludge, hospital wastewaters, surface waters, and drinking water. PCT can cause genetic code damage, oxidative degradation of lipids, and denaturation of protein in cells, and its toxicity has been well-proven in bacteria, algae, macrophytes, protozoan, and fishes. To avoid its harmful health problems over living beings, powerful Fenton and Fenton-based treatments as pre-eminent advanced oxidation processes (AOPs) have been developed because of the inefficient treatment by conventional treatments. This paper presents a comprehensive and critical review over the application of such Fenton technologies to remove PCT from natural waters, synthetic wastewaters, and real wastewaters. The characteristics and main results obtained using Fenton, photo-Fenton, electro-Fenton, and photoelectro-Fenton are described, making special emphasis in the oxidative action of the generated reactive oxygen species. Hybrid processes based on the coupling with ultrasounds, gamma radiation, photocatalysis, photoelectrocatalysis, zero-valent iron-activated persulfate, adsorption, and microbial fuel cells, are analyzed. Sequential treatments involving the initiation with plasma gliding arc discharge and post-biological process are detailed. Comparative results with other available AOPs are also described and discussed. Finally, 13 aromatic by-products and 9 short-linear aliphatic carboxylic acid detected during the PCT removal by Fenton and Fenton-based processes are reported, with the proposal of three parallel pathways for its initial degradation.
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•Paracetamol removal by Fenton, photo-Fenton (PF), and (photo)electro-Fenton up to 2021.•High degradation by homo- and hetero-Fenton, larger mineralization by homo- and hetero-PF.•Good degradation and mineralization by electro-Fenton, improved by photoelectro-Fenton.•Hybrid processes with photocatalysis, photoelectrocatalysis, ultrasounds, and gamma radiation.•3 initial degradation pathways for paracetamol proposed from 13 detected aromatic by-products.
Artisanal mining is the main source of mercury emissions in South America, which generates a serious environmental impact due to this toxic metal, recent research is directed to minimize the impact, ...therefore this study focuses on the green synthesis of nanoparticles for the absorption of mercury in water. For the synthesis of iron nanoparticles, an extract of Eucalyptus grandis was used with iron chloride salts using water as solvent. The synthesized nanoparticles showed a specific surface area of 131.90 m2/g, determined by Brunauer-Emmett-Teller isotherm (BET). Nanoparticles were characterized by Fourier transformed infrared spectroscopy (FTIR) and transmission electron microscopy (MET). The behavior of nanoparticles synthesized during Hg (II) retention was evaluated measuring pH, temperature, nanoparticle dosing, presence of other ions and comparing with other adsorbents. All analyses measured by atomic absorption spectroscopy by the cold vapor technique (CVAAS), presenting a retention percentage for Hg (II) between 75.05 and 79.59% with pH between 4 and 7. The adsorption isothermal was adjusted to the Freundlich model and the percentage of retention of Hg by the synthesized nanoparticle was 79.26%. This work shows a method for obtaining an environmentally friendly mercury adsorbent from iron and E. grandis with a mercury retention capacity comparable to commercial adsorbents.
Nanoparticles; Iron; Adsorption; Mercury; Mining, Water.
Copolymerization of xylitol usually yields cross-linked materials. In this work, microwave-assisted polyesterification of xylitol and succinic acid produced materials with diverse molecular weights ...and different branching degrees, and more importantly, no cross-linking was observed, as supported by the solubility behavior and spectroscopic data. Reactions were carried out for short times, less than 20 min, which is not common for production of industrial polyesters. Control over the branching degree was achieved by tuning the reaction conditions, such as temperature, time of exposure, and monomer ratio, during microwave irradiation. No solvent or catalyst was employed during the step-growth polymerization.
Recent studies have indicated that starch from legumes can potentially be used as an alternative to commercial flour with applications in food and biomaterials; however, some modifications may be ...required first to improve their functionality, as they show relatively lower solubility and functional properties compared to commonly marketed flours (e.g. good water retention capacity). This work used multiple enzymes in flour extracts of pigeon pea (Cajanus cajan), a legume, to optimize the enzyme hydrolysis process of such extracts by the Response Surface Method (RSM), to increase the digestibility and obtain desirable functional attributes at the nutritional level. The pH, temperature, time and enzyme/substrate (E/S) ratio were evaluated, and the degree of hydrolysis (DH) was calculated as well as the reducing sugar content (%RS), used as response variable. According to the experimental design, the best pH, temperature, time and E/S ratio were 6.8, 43 °C, 1.84% m/m and 270 min, respectively. The %RS for the samples under optimal conditions was 3.49 ± 0.02%, and the in vitro digestibility yielded values of 39.2 ± 0.4, 58.6 ± 0.3 and 2.2 ± 0.2 for slowly digestible starch (SDS), rapidly digestible starch (RDS) and resistant starch (RS), respectively. Total digestibility (TD) was 97.8 ± 0.5. The statistical analysis revealed a strong positive relationship for E/S ratio followed by pH: (E/S) ratio, temperature and pH. Enzymatic hydrolysis carried out on pigeon pea showed an increase in TD. Viscosity, water retention capacity (WRC) and solubility were evaluated showing good response for future applications at the industrial level.
Enzymatic hydrolysis; Starch; Pigeon pea; Total digestibility
A medida que como sociedad vamos dando más importancia a lograr una economía circular, se hace importante encontrar fuentes renovables aptas para la producción de biocombustibles y bioquímicos. En ...los últimos años, diversas fuentes de biomasa lignocelulósica han sido estudiadas para estos propósitos. Dentro de estas fuentes de biomasa se encuentra el cáñamo (Cannabis sativa L.), siendo parte de una industria que ha crecido a pasos agigantados en las últimas décadas, en Colombia, desde su legalización. Específicamente, la industria del cannabis medicinal es responsable de generar una enorme cantidad de residuos en forma de los tallos de la planta, considerados un subproducto de bajo valor. En esta revisión se compila la información de diferentes estudios sobre el aprovechamiento de la fracción de polisacáridos de biomasa cáñamo, mediante transformaciones químicas y bioquímicas, para la obtención de productos de valor agregado. Se encontró que la mayoría de estudios están enfocados en la obtención de bioetanol o biogás; se encontraron también reportes de otras moléculas como ácido succínico, ácido láctico, furfural, polihidroxialcanoatos y bisaboleno. La viabilidad a nivel industrial de todos estos procesos permanece siendo una incógnita, pues los pasos de pretratamiento, hidrólisis y de conversión final utilizados suelen ser costosos. Es necesario que los estudios que realicen en el futuro se enfoquen en optimizar las condiciones de estos procesos y hacerlos verdes y así asegurar que puedan ser escalados. Palabras clave: Cannabis sativa, lignocelulosa, biorefinería, hidrólisis enzimática, bioproductos.
El presente trabajo busca abordar el sistema de inserción estratégica de los países del golfo Pérsico en el cuerno de África, mediante un enfoque multidimensional que permita entender cómo dichas ...estrategias son flexibles y pragmáticas, en tanto dependen, en gran medida, de la cooperación o resistencia de los actores que se encuentran involucrados. Los países africanos son actores activos en el proceso de inserción estratégica de Estados extra-regionales con intereses en la zona, por lo que pueden definir los alcances de las políticas aplicadas, adquiriendo un mayor margen de negociación, en la medida que varias políticas de inserción se focalizan en temas o puntos geográficos específicos. Analizar cómo se transforman las relaciones entre estos actores, permite reflexionar y visibilizar el rol que tienen los Estados africanos para condicionar las políticas de influencia de actores extra-regionales.
Pig bone residue is considered a potential source of hydrolysates from its protein with added value uses in the food industry. This work deals with the enzyme hydrolysis of pig bone protein. The ...conditions for extracting the protein hydrolysate were optimized and the equation obtained allowed samples with different degrees of hydrolysis (DH) to be extracted to study how the biological properties of in-vitro hydrolized protein affected digestibility, determination of the inhibitory activity of the angiotensin-converting enzyme and the antioxidant activity and its functional properties. It was found that the emulsifying capacity and emulsion stability increased at intermediate DH values, after which these properties decreased with the increase in DH. The in-vitro digestibility and angiotensin-converting enzyme (ACE) of the hydrolysates are also clearly affected by the DH. The amino acid composition of the hydrolized protein is also determined.
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