Synthesis and Thermal Characterization of Polyurethanes Obtained from Cottonseed and Corn Oil-Based Polyols

The use of vegetable oils to replace fossil feedstock has become an area of opportunity and a priority for study in the field of polymer science. Vegetable oils are considered as renewable resources with high potential, low cost and full availability. The aim of this study is the synthesis of biobased polyols from cottonseed oil (Gossypium barbadanse) and corn oil (Zea mays) as feedstock. Their synthesis was successfully performed, as can be concluded from the determination of their hydroxyl index as well as the structural and thermal characterization carried out in this work. Polyurethanes from biobased polyols were synthesized with two different isocyanates (HDI and MDI) and variable polyol/isocyanate ratio and they were further characterized by infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy, concluding that cottonseed and corn oils could be considered as valid alternatives for the synthesis of biobased polymeric materials.The authors thank the Spanish Ministry of Economy and Competitiveness (MAT2014-59242-C2-2-R) and CONACYT-Mexico (No.CB06825 and doctoral scholarship No.234299/212279) for their financial support

Importancia de las levaduras no-Saccharomyces durante la fermentacion de bebidas alcoholicas

Durante la fermentación de bebidas alcohólicas intervienen principalmente levaduras del genero Saccharomyces. Sin embargo, existen otros géneros de levaduras que también participan en los procesos fermentativos, y rara vez son tomados en cuenta, estas son las levaduras denominadas no-Saccharomyces, entre las que destacan: Kloeckera apiculata, Hanseniaspora uvarum, Rhodotorula glutinis, Rhodotorula mucilaginosa, entre otras; las cuales mediante la producción de congenéricos, enzimas y proteínas pueden enriquecer organoléptica y nutricionalmente las bebidas alcohólicas, lo que ayudaría a satisfacer el paladar de los consumidores más exigentes. (Résumé d'auteur

Characterization of three novel pigment-producing Penicillium strains isolated from the Mexican semi-desert

Fungal pigments are used in diverse industries such as food, pharmaceuticals, textile, among others. The need of new organic pigments involves the search for new microbial sources. In this study, three fungal strains isolated from Quercus sp and Larrea tridentata were morphological, physiological and molecularly characterized. Different temperatures (8, 16, 20, 24 and 32°C) and pH (4, 6, 7, 8 and 10) levels were tested to determine the best conditions to produce a fungal pigment under submerged and solid state fermentation. The three strains were genotyped by using polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP), random amplified polymorphic DNA (RAPD), inter-transcript spaces (ITS) and intergenic spaces (IGS) with the object to eliminate duplications. The strains were identified according to their morphology as Penicillium purpurogenum (GH2) and Penicillium pinophilum (EH2 and EH3). It was found that at submerged state fermentation to 24°C and pH 10, the three strains produced pigments, but P. purpurogenum GH2 strain produced the highest amount of pigments (1.25 U). According to the molecular analysis, it was found that all strains were different. This is to our knowledge the first report on characterization of fungal strains isolated from the Mexican semi-desert which have potential for pigment production.Keywords: Penicillium purpurogenum, Penicillium pinophilum, intergenic spaces (IGS), inter-transcript spaces (ITS), pigments, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), submerged and solid state fermentationAfrican Journal of Biotechnology Vol. 12(22), pp. 3405-341

Edible film based on candelilla wax to improve the shelf life and quality of avocado

In this study the effect of addition of ellagic acid (at three different concentrations) into candelilla wax matrix on shelf life and quality of whole avocados was studied. Control treatments were avocados coated with candelilla wax without ellagic acid and avocados without coating. The fruits were chosen for their maturity, size, free from infection and physical defects. All those samples were inoculated with a concentrated suspension of spores of Colletotrichum gloeosporioides, the main phytopathogenic fungus for avocados. Experiments were carried out completely divided into randomized groups. Changes in appearance, solids content, pH, aw, lightness (L* value) and weight loss were monitored during 6 weeks every 8 days. A sensory evaluation of avocados coated with the best edible film was also performed. Edibel films were able to reduce significantly the damage caused by C. gloeosporioides, reducing also significantly the change in appearance and weight loss in the fruits. Use of ellagic acid as part of the edible film has an important effect to improve the quality and shelf life of avocado. With this work we found that using this new protection system the negative effects of C. gloeosporioides can be successfully reduced

Polyphenolic content, in vitro antioxidant activity and chemical composition of extract from Nephelium lappaceum L. (Mexican rambutan) husk

Objective: To determinate the recovery of total polyphenolic compounds content, in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from Nephelium lappaceum L. (Mexican rambutan). Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI methods. In vitro antioxidant activity was performed using ABTS and ferric reducing antioxidant power methods. Results: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTS and ferric reducing antioxidant power analysis. The HPLC/ESI/MS assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample; the mineral composition was also evaluated. Conclusions: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potentialapplications as bioactive antioxidant agents for the treatment of diseases

Efecto del medio ambiente sobre la composición química y propiedades físicas del grano de maíz poliembriónico

La poliembrionía, ha sido reportada en el maíz (Zea mays L.) desde el siglo XX. Este rasgo se define como la aparición de dos o más plántulas de una semilla germinada, y se ha asociado con mejoras en el contenido nutricional del grano. Las características del grano de maíz son afectadas por diferentes factores, entre ellos la localidad de cultivo. Por lo tanto, es importante determinar el efecto del ambiente (localidad) en las características de los granos poliembriónicos. El propósito de este estudio fue determinar los efectos ambientales sobre las propiedades físicas y químicas de los granos de maíz poliembriónicos. Se sembraron 32 genotipos de maíz con diferentes niveles de poliembrionía (alta, baja y sin poliembrionía) en dos localidades diferentes (Buenavista, Coahuila y Río Bravo, Tamaulipas, México). Los resultados mostraron que, en la ubicación de Buenavista, las líneas de maíz tenían un peso mayor de mil granos (272 - 367 g) las líneas no poliembriónicas mostraron el mayor peso. En las líneas de maíz de baja poliembrionía el tamaño del grano fue mayor con embriones más grandes que ocupaban un espacio entre 11.37-11.59%. En Río Bravo, en comparación con Buenavista, las líneas de maíz poliembriónico tuvieron el mayor contenido de proteína (4.56%), grasa (5%) y fibra cruda con (1.2%) más alta en el maíz no poliembriónico. En Buenavista, el contenido de almidón fue de (59.2%) mayor en el maíz no poliembriónico, con (1.4%) de cenizas y la humedad de (13.7%) que fueron mayores en el maíz poliembriónico. Al cultivar genotipos de maíz poliembriónico en diferentes ambientes, se observó que el perfil bromatológico se ve afectado por las condiciones ambientales. En este estudio, se observó un mejor contenido nutricional en los genotipos de maíz cultivados en Río Bravo, en comparación con los genotipos de maíz cultivados en Buenavista. Por lo tanto, este estudio sugiere que es posible producir genotipos de maíz poliembriónico en diferentes ambientes y aunque tuvieron un perfil bromatológico diferente pueden emplearse para usos industriales específicos.Polyembryony has been reported in maize (Zea mays L.) since the 20th century. This trait is defined as the appearance of two or more seedlings from a germinated seed and has been associated with improvements in the nutritional content of the grain. Maize kernel traits are affected by different factors among them the growing location. Thus, it is important to determine the environmental (location) effect on polyembryonic kernel traits. The purpose of this study was to determine the environmental effects on the physical and chemical properties of polyembryonic maize kernels. Thirty-two maize genotypes with different levels of polyembryony (high, low and non-polyembryonic) were planted in two different locations with distinct climate (Buenavista, Coahuila and Río Bravo, Tamaulipas, Mexico). Results showed that at the Buenavista location, maize lines had a greater weight of one thousand grains (272 - 367 g), the non-polyembryonic lines showed the highest weight. Besides, the low polyembryonic maize lines promoted the largest grain dimensions. The polyembryonic maize had the biggest embryos, which occupied 11.37 -11.59% of the grain. At the Río Bravo, in comparison to Buenavista, the polyembryonic maize lines had the highest protein (4.56%) and fat (5%) contents, while the raw fiber (1.2%) was highest in non-polyembryonic maize, meanwhile at, the Buenavista location, the starch content (59.2%) was higher in non-polyembryonic maize, while ashes (1.4%) and moisture (13.7%) were higher in polyembryonic maize. Growing polyembryonic maize genotypes in different environments, it was observed that the bromatological profile is affected by environmental conditions. In this study, a better nutritional content was observed in maize genotypes grown at Río Bravo in comparison to those maize genotypes grown at Buenavista. So, this study suggests that it is possible to produce polyembryonic maize genotypes in different environments which will have a different bromatological profile and can be employed for specific industrial uses

Propiedades antioxidantes de infusiones de neem (Azadirachta indica) encapsuladas con proteína de soya

Abstract Introduction: Plants contain phytochemicals with healing properties, although not scientifically proven. Neem (Azadirachta indica) is a plant, which has been reported to have antioxidant activity leaves. The aim of this study was to evaluate the polyphenol content and antioxidant activity of neem extracts and determine the optimal infusion time to preserve the antioxidant activity of the active compounds in infusions of fresh and dry wall material using neem for encapsulation. Method: Fresh and dried neem leaves were used to prepare infusions at 0, 3 , 5, 8 , 10, 12 and 15 minutes, which are determined ° Bx , pH , color intensity, content of polyphenols by method of Folin-Ciocalteu and antioxidant activity by the rate of uptake of the stable 1,1-diphenyl-1-picryl-hydrazyl (DPPH) radical. In the infusions higher content of antioxidant compounds were added 1.0, 1.5, 2.0, 2.5 and 3.0 % soy protein as wall material and stored for 16 days. Every third day they evaluated the polyphenol content, antioxidant activity and percentage inhibition. Results: The increased release of active compounds from neem dry leaves was obtained after 8 minutes of infusion. When using fresh leaves for the infusions, the optimal time was 12 minutes, their inhibition percentage was 41.09%, and with infusions of dry leaves, at time 0 and 3 were 60.59% and 64.73% inhibition respectively, and at 15 minutes 86.81%. The content of phenolic compounds, antioxidant activity and percent inhibition were lower in infusions with wall material compared to infusions in which no wall material was added. Discussion or Conclusion: Infusions from dried neem leaves are a good natural source of phenolic compounds. Likewise, the use of wall materials such as soy protein is presented as an alternative to preserve the phenolic compounds present in neem.Resumen Introducción: Las plantas contienen fitoquímicos con propiedades curativas, aunque no todas han sido comprobadas científicamente. El neem (Azadirachta indica) es una planta, de la cual se ha reportado que sus hojas tienen actividad antioxidante. El objetivo de este trabajo fue evaluar el contenido de polifenoles y la actividad antioxidante de infusiones de neem, así como determinar el tiempo óptimo de la infusión para conservar la actividad antioxidante de los compuestos activos en infusiones de neem fresco y seco usando material de pared para su encapsulación. Método: Para preparar infusiones de 0, 3, 5, 8, 10, 12 y 15 minutos se usaron hojas frescas y secas de neem. A las infusiones se les determinaron sólidos totales, pH, intensidad de color, contenido de polifenoles por el método de Folin-Ciocalteau y actividad antioxidante mediante el porcentaje de captación del radical estable 1,1 difenil-1-picril hidrazilo (DPPH). A las infusiones con mayor contenido de compuestos antioxidantes, se les añadieron 1.0, 1.5, 2.0, 2.5 y 3.0% de proteína de soya como material de pared y se almacenaron por 16 días. Cada tercer día se les evaluó el contenido de polifenoles, actividad antioxidante y porcentaje de inhibición. Resultados: La mayor liberación de compuestos activos a partir de las hojas secas de neem se obtuvo a los 8 minutos de infusión. Al usar hojas frescas para las infusiones el tiempo óptimo de éstas fue de 12 minutos, su porcentaje de inhibición fue de 41.09 %, y con las infusiones de hojas secas, al tiempo 0 y 3 se tuvieron 60.59% y 64.73% de inhibición respectivamente, y a los 15 minutos un 86.81 %. El contenido de compuestos fenólicos, actividad antioxidante y porcentaje de inhibición, fueron menores en las infusiones con material de pared en comparación con las infusiones en las que no se agregó material de pared. Discusión o Conclusión: Las infusiones de neem a base de hojas secas son una buena fuente de compuestos fenólicos. Así mismo, el empleo de materiales de pared como la proteína de soya se presenta como una alternativa para conservar los compuestos fenólicos presentes en el neem

Production, Stabilization, And Uses Of Enzymes From Fruit and Vegetable Byproducts

Publisher Copyright: © 2016 Elsevier Inc. All rights reserved.Microbial enzymes are preferred due to their economic feasibility, high yields, consistency, ease of product modification and optimization, regular supply due to absence of seasonal fluctuations, rapid growth of microbes on inexpensive media, stability, and greater catalytic activity. Enzymes with desired activity under industrial conditions have been obtained. These enzymes have been achieved in several ways, isolating new microorganisms, often thermotolerant, by searching in metagenomic libraries for new gene sequences, or by mutagenesis, screening for optimizing process conditions, and by protein engineering. The use of enzymes frequently results in many benefits that cannot be obtained with traditional chemical treatment. These often include higher product quality and lower manufacturing cost, less waste, and reduced energy consumption. Key factors driving the market growth include new enzyme technologies endeavoring to enhance cost efficiencies and productivity, and growing interest among consumers in substituting petrochemical products with other organic compounds such as enzymes.Peer reviewe