The aim of this study was to extract mucilage from O. cochenillifera (L.) cacti and determine its functional and physicochemical properties. The best mucilage yield (31%) was obtained by nonthermal extraction with hydration. The mucilage has appreciable carbohydrate and protein contents. The phytochemical analysis shown the presence of alkaloids and terpenes/steroids. The Fourier transformed infrared (FT-IR) spectrum of the mucilage exhibits typical bands for carbohydrates as O–H, C–H, and –COO−. The mucilage demonstrated water- and oil-holding capacities of 2.78 g water/g dry mucilage and 1.80 g oil/g dry mucilage, respectively, these properties can have a positive effect on the texture of the products when used as a stabilizer. The mildly acidic pH (4.8–5) contributes to its emulsifying capacity. The presence of electrolytes in the mucilage can be of great value in flocculation processes. The mucilage forms low viscosity solutions in the same manner as gum Arabic. Finally, its potential for use as a textile dye remover was evaluated, achieving a 70% removal rate from aqueous solutions. The prepared mucilage exhibits properties that recommend it as a natural material that can be used as an additive in the chemical, food, pharmaceuticals and cosmetics industries, as well as in decontamination processes.

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Upon mutation of Asn130 to aspartate, the catalytic activity of human arginase I was reduced to ∼ 17% of wild‐type activity, the Km value for arginine was increased ∼ 9‐fold, and the kcat/Km value was reduced ∼ 50‐fold. The kinetic properties were much less affected by replacement of Asn130 with glutamine. In contrast with the wild‐type and N130Q enzymes, the N130D variant was active not only on arginine but also on its decarboxylated derivative, agmatine. Moreover, it exhibited no preferential substrate specificity for arginine over agmatine (kcat/Km values of 2.48 × 103 m−1·s−1 and 2.14 × 103 m−1·s−1, respectively). After dialysis against EDTA and assay in the absence of added Mn2+, the N130D mutant enzyme was inactive, whereas about 50% full activity was expressed by the wild‐type and N130Q variants. Mutations were not accompanied by changes in the tryptophan fluorescence properties, thermal stability or chromatographic behavior of the enzyme. An active site conformational change is proposed as an explanation for the altered substrate specificity and low catalytic efficiency of the N130D variant.

The kraft pulping process was evaluated in this study as a pretreatment of Eucalyptus globulus for bioethanol production. Wood chips were pretreated under different pulping conditions (155°C and 165°C; 15 and 20 % alkali active AA, 15-60 min). A total of 12 pulps were obtained, with pulp yields ranging from 49 to 57%. Glucan remained in pulps were from 77% and 90%, while 50% of the hemicelluloses were solubilized. Lignin removal increased with increased severity of cooking (high active alkali charge, pretreatment time and temperature) reaching delignification over 78%. The enzymatic hydrolysis of kraft pulps with cellulase presented a rapid glucan conversion rate to glucose with values over 90%. Lignin, hemicellulose removal, as well as, cellulose polymerization degree showed an effect on the increment of enzymatic hydrolysis. The degree of crystallinity increased slightly between 1-5%, having no effect on the enzymatic hydrolysis. The simultaneous saccharification and fermentation was performed (SFS) at 10% substrate consistency with a production at 30-38 g ethanol/L. The maximum amount of ethanol that could be produced from E. globulus is 258 g ethanol/kg wood, assuming total glucose conversion into ethanol. The amounts of ethanol obtained from the different pulps varied between 168-202 g ethanol/kg wood. The ethanol yields obtained from kraft pulps varied between 65 and 78% (wood basis). The maximum ethanol yield was 78% at 155°C, 15% AA and 60 min reaction, while the yield was 74% at 165°C, 15% AA and 30 min of reaction time. Results showed that an efficient enzymatic hydrolysis at low enzyme loads could be obtained from kraft pulps employing less severe conditions than those used to produce bleachable -grade pulps.

This article shows the methodology and the main figures of the local and regional economic impact generated by cruise activity. This article is pioneering in combining different issues: estimating the impact of the cruise port activity, presenting these impacts disaggregated at a sectoral level, using a rigorous methodology and carrying out extensive fieldwork. It is demonstrated that all sectors, not just traditional tourism-related sectors, benefit from cruise tourism. In order to test and apply our methodology we focus the analysis in The Port of Barcelona, which has become the leading cruise port in the Mediterranean area.