Search

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica 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 Ciência Agronômica is the property of Revista Ciencia Agronomica 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.)

Abstract The present study was designed to evaluate the therapeutic potential of bioactive compounds from chloroform extract of the leaves of Hylocereus undatus in the formation of advanced glycation end products (AGEs) in vitro. Bioactivity-guided fractionation of chloroform extract from Hylocereus undatus afforded two novel 12-ursen-type triterpenes, 3 β , 16 α , 23-trihydroxy-urs-12- en-28-oic acid (1) and 3 β , 6 β , 19 α , 22 α -tetrahydroxy-urs-12-en-28-oic acid (2), as well as four known triterpenes 2 α , 3 β , 23-tetrahydroxy-urs-11-en-28-oic acid (3), 3 β -acetoxy-28-hydroxyolean-12-ene (4), 3 β , 16 α -dihidroxyolean-12-ene (5) and 3 β -acetoxy-olean-12-ene (6). Our results revealed that triterpenes 1 – 3 were able to inhibit the formation of AGEs in all tested assays. The data indicated that the triterpenes had inhibitory activity at the múltiple stages of glycation and that there might be a high potential for decreasing protein oxidation and protein glycation that can enhance glycative stress in diabetic complications. [ABSTRACT FROM AUTHOR]

α-Amylase is a significant enzyme with numerous commercial applications, which is largely used to convert starches into oligosaccharides. So, purification of α-Amylase from by products or cheap sources is of great importance due to its ease of production and industrially widespread applications. In the present study, α-amylase was purified from white pitaya peel in a system composed of two phase based on salt and polyethylene glycol. Furthermore, the impact of four independent variables, including (X 1 ) polyethylene glycol molecular weight (4000–8000 g/mol), (X 2 ) polyethylene glycol concentration (10–18% (w/w)), (X 3 ) sodium citrate concentration (12–20% (w/w)), and (X 4 ) NaCl (2–8% (w/w)), on partition coefficient (Y 1 ), purification factor (Y 2 ) and yield (Y 3 ) of the purified enzyme was investigated using central composite design of response surface methodology. Results showed that optimum conditions for amylase purification were that, 14% (w/w) polyethylene glycol 6000 (g/mol), 16% (w/w) sodium citrate and 5% (w/v) NaCl; the partition coefficient, purification factor and amylase yield under the optimal conditions were 6.62%, 4.43% and 89.12%, respectively. Moreover, the experimental and predicted results were in considerable agreement, which established the reliability and validity of the proposed model. This study indicated that the citrate-based aqueous two-phase system provides a promising tool for effective purification of amylase at a low cost with a large loading capacity. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica 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 Ciência Agronômica is the property of Revista Ciencia Agronomica 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.)

The objectives of the present survey were to study the production and the biochemical characterization of an enzymatic cold-active extract with polygalacturonase activity, to perform a first insight into its possible application in fruit-juice obtention process, and to use this juice for food products preparation. The enzymatic extract was produced by the Antarctic yeast Mrakia sp. LP January 7, 2016 in a bioreactor with citric pectin as substrate. The polygalacturonase activity showed optimum conditions for reaction at 45 °C and pH 5.0. This activity was stable until 40 °C but deactivated at higher temperatures. Inhibition by Hg+2 suggested the presence of a thiol-dependent enzyme. A high-molecular polygalacturonase was detected in an SDS-PAGE and zymography analysis. Reaction-products were observed by thin-layer chromatography and suggested the endo -mode of action. The enzymatic extract had some accessory enzymes, such as pectin methylesterase, β-glucosidase, cellulase and inulinase. As a first insight into the potential use of this enzymatic extract for fruit maceration at mild temperatures, red and white dragon fruits were selected as models. At 23 °C, juice yields of 15%–23% higher than control were obtained after treatments, with a decrease of remanent solid of 25%–35%. The color of red dragon fruit juice increased with enzymatic treatment. Alginate balls that were prepared with the juices demonstrated a hardness of ∼10 N. The compression force of low-calorie sugar gels was 3.8 N. This work provided a complete study of the production, characterization, application and food product production using a new cold-active polygalacturonase extract of Antarctic origin. [ABSTRACT FROM AUTHOR]

The pitaya peel (Hylocereus undatus) was carbonized in the presence of ZnCl 2 to obtain a carbon-based adsorbent to remove the Metanil Yellow dye (MY) from colored waters. The characterization techniques confirmed that the material had morphological changes with the appearance of new irregularities and cavities. Besides, the alternative adsorbent was formed mainly by carbon and functional groups characteristic of lignin and cellulose. Isothermal and kinetic studies were carried out at the natural pH of the solution at a dosage of 0.4 g L−1. The Langmuir model demonstrated the best adjustment of the equilibrium isotherms of the system, reaching the maximum adsorption capacity of 144.07 mg g−1 at 298 K. The thermodynamic behavior indicated that it is a spontaneous and favorable process of an exothermic nature (Δ H 0 =−34.02 kJ mol−1), consistent with a mechanism involving electrostatic interactions. The MY concentration influenced the kinetic. The homogeneous surface diffusion model (HSDM) showed good statistical adjustment to the kinetic values, showing a slight increase in the diffusivity coefficient from 2.4 × 10−9 to 4.5 × 10−9 cm2 s−1 with the increased MY concentration. The material application in a mixture containing several dyes and salts in the circumstances close to the real ones showed removal of 82.5%. The adsorbent could be regenerated and used 12 times. Therefore, it can be concluded that the pitaya fruit residual biomass can be used as a precursor for preparing carbon-based adsorbents. The adsorbent, in turn, is a promising alternative in the treatment of MY dye and mixtures of organic molecules. [Display omitted] • A microporous carbon-based adsorbent was developed from pitaya peels. • The adsorbent was efficient in uptake Metanil Yellow dye from effluents. • Maximum adsorption capacity was 144.07 mg g−1. • Excellent adsorption performance in simulated effluents. • The material can be used 12 times. [ABSTRACT FROM AUTHOR]