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Copyright of Revista Mexicana de Ingeniería Biomédica is the property of Sociedad Mexicana de Ingenieria Biomedica, A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Química is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thermoplastic starch (TPS) has emerged as an essential alternative to produce environmentally friendly packaging; however, retrogradation is a disadvantage that affects its shelf life. This study analyzed the co-plasticizing effect of isosorbide on the mechanical, thermal, physicochemical, and microstructural properties and the retrogradation of films obtained by blown film extrusion from thermoplasticized starch with mixtures of glycerol and isosorbide in different ratios (3:0, 2:1, 1:2, and 0:3, respectively). The results showed that the higher concentration of isosorbide significantly increased the tensile strength; however, it reduced the elongation. Retrogradation modeled using the Avrami equation showed that the presence of isosorbide reduced the retrogradation rate (k) and modified the recrystallization mechanism (n). The relative crystallinity in the plasticized TPS films was reduced to 89%, and the adsorption significantly decreased. Isosorbide was very important in reducing the retrogradation of TPS. The best performance was obtained with the 2:1 ratio of glycerol/isosorbide due to the synergistic effect between the plasticizers. The results would allow tuning the properties of TPS films by combining glycerol/isosorbide in different ratios, which enables the design of materials tailored to potential application requirements. [ABSTRACT FROM AUTHOR]

Coffee pulp is rich in bioactive compounds. Currently, the use of "green methodologies" is being sought that promote cleaner, safer extraction protocols with lower energy consumption. The present study proposes the extraction of polyphenolic compounds from the coffee pulp through the use of methodologies such as ultrasound and microwave. Different extraction conditions were evaluated, varying the mass:volume ratio and the water:ethanol ratio. The mineral content, the amount of total and condensed polyphenols was determined as well as the characterization of the coffee pulp polyphenolic extracts by FT‐IR, and HPLC‐MS. The main mineral in the coffee pulp was potassium. The total content of polyphenols using ultrasound‐microwave extraction was 165.2‐328.9 mg GAE/g, where the best ratio was 1:16 m/v and the water/ethanol ratio showed no difference in the levels of polyphenol extraction. Likewise, for condensed polyphenols, values between 10.06‐20.52 mg CE/g were obtained. The main polyphenols were 3‐p‐coumaroylquinic acid, 3‐feruloylquinic acid, quercetin 3′,7‐dimethyl ether, (+)‐gallocatechin, 2,3‐dihydroxybenzoic acid, (–)‐epicatechin‐(2a‐7)(4a‐8)‐epicatechin 3‐O‐galactoside, and 1,3‐dicaffeoylquinic acid. Therefore, the coffee pulp can be used to obtain bioactive compounds through green methodologies such as ultrasound and microwave. [ABSTRACT FROM AUTHOR]

Exopolysaccharides (EPS) are biopolymers produced by many microorganisms, including some species of the genus Acetobacter, Bacillus, Fructobacillus, Leuconostoc, Lactobacillus, Lactiplantibacillus, Pediococcus, Pichia, Rhodotorula, Saccharomycodes, Schizosaccharomyces, and Sphingomonas, which have been reported in the microbiota of traditional fermented beverages. Dextran, levan, glucan, gellan, and cellulose, among others, are EPS produced by these genera. Extracellular biopolymers are responsible for contributing to specific characteristics to fermented products, such as modifying their organoleptic properties or contributing to biological activities. However, EPS can be easily found in the dairy industry, where they affect rheological properties in products such as yogurt or cheese, among others. Over the years, LAB has been recognized as good starter strains in spontaneous fermentation, as they can contribute beneficial properties to the final product in conjunction with yeasts. To the best our knowledge, several articles have reported that the EPS produced by LAB and yeasts possess many both biological and technological properties that can be influenced by many factors in which fermentation occurs. Therefore, this review presents traditional Mexican fermented beverages (tavern, tuba, sotol, and aguamiel) and relates them to the microbial EPS, which affect biological and techno-functional activities. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the insecticidal activity of the polyphenolic compounds found in neem on S. frugiperda larvae. Three neem extracts (1:12 (m/v) with 70% ethanol, 1:12 (m/v) with 0% ethanol (only water), and 1:4 (m/v) with 0% ethanol) were employed. Subsequently, the extraction of phytochemical compounds of each extract was performed using ultrasound and microwave technologies simultaneously. The compound characterization was performed by HPLC-mass. In addition, the insecticidal evaluation of the neem extract was performed against S. frugiperda of the second-stage larvae. The extracts were applied by spraying the larvae according to each bioassay. Results showed that the extract obtained with a 1:12 (m/v) relationship and 70% ethanol was effective for the control of S. frugiperda larvae. In this extract, the predominant organic compound families were: methoxyflavones, flavonols, hydroxycoumarins, anthocyanins, methoxycinnamic acid, and alkylflavones. Phytochemical compounds obtained from neem seeds with environmentally friendly solvents and alternative technologies (ultrasound and microwave) have potent insecticidal activity against S. frugiperda larvae. [ABSTRACT FROM AUTHOR]

Mannich bases are formed in a noncatalytic multicomponent reaction, which is promoted by ultrasound irradiation. The procedure avoids the use of toxic solvents, catalyst, and purification, generating the desired compounds in excellent yields and short reaction times. [ABSTRACT FROM PUBLISHER]

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Vitae (01214004) is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Films formulated with edible natural waxes extracted from Euphorbia antisyphilitica, and additives Aloe vera (4%), ellagic acid (0.01%) and gallic acid (0.01%) were applied to evaluate their effects on the quality of fresh-cut fruits stored at 5C and at room temperature (21C) for 6 days. The evaluated characteristics were changes in appearance, weight loss, firmness, color, solid content, pH and water activity (A w). The additives, combined with the natural wax, demonstrated not to cause apparent damage to the fruits. Generally speaking, the films showed better results in comparison with the control. The treatment with A. vera showed the lowest values in weight loss, water migration, A w, change in pH and firmness. The ellagic acid coating reduced the color change in a greater proportion. The application of these new edible films to fruits extends their shelf life and increases their antioxidant potential, as well as their nutritional quality. PRACTICAL APPLICATIONS Edible films elaborated with a natural wax extracted from Euphorbia antisyphilitica complemented with a potent antioxidant ellagic and gallic acids, and Aloe vera extend the shelf life quality and increase the antioxidant potential, as well as the nutritional quality of fresh-cut fruits and vegetables, giving way to the possibility of producing nutraceutical products in the form of edible biofilms. Potential applications of these films are very attractive because the components are natural and nontoxic, and they are recommended by their low cost, availability and ease of handling. The possibility of using these films on other food products, not necessarily vegetal in origin, could be assayed. [ABSTRACT FROM AUTHOR]

In the present work, multiple-wall carbon nanotubes (MWCNTs) were surface modified in an environmentally friendly way, using low-frequency ultrasonic energy. This type of modification was carried-out using two different types of organic acids, citric acid (CA) and oxalic acid (OA). The modification of the MWCNTs was confirmed by Fourier-transform infrared spectroscopy (FTIR), where functional groups such as OH, C=O, O–C=O and COOH were detected. By means of Raman spectroscopy, an increase in carbon surface defects was found. On the other hand, using X-ray photoelectron spectroscopy (XPS), oxidation was evidenced on the surface of the modified MWCNT. In both Raman spectroscopy and XPS, the results indicate a greater modification when CA is used, possibly due to the fact that CA has a larger number of functional groups. MWCNT-CA showed good dispersion in methanol, while MWCNT-OA showed good stability in methanol and ethanol. Finally, a 20% removal of creatinine efficiency improvement was found with respect to the unmodified MWCNTs, while no improvement was found in the case of urea and uric acid. [ABSTRACT FROM AUTHOR]