Evaluation of porcine albumin as a partial replacement for egg white in chocolate cakes

Se analizó el efecto de la sustitución de clara de huevo por albúmina sérica porcina (ASP) en panqués de chocolate. La ASP se obtuvo mediante un método escalado de aislamiento por cromatografía de interacción hidrofóbica. En la formulación del panqué se reemplazó el 50 y 100% de la clara de huevo con ASP. Todos los panqués presentaron valores similares (P >0.05) de los parámetros de color en la miga: L (25,7-26,2), a* (9,8-10,1) y b* (14,5-15,0) y en la costra: L (25,7-26,2), a* (9,8-10,1) y b* (14,5-15,0). La textura (2,9 N) y el volumen (148,9 ± 1,8 cm 3) de los panqués con 50% de ASP fueron similares (P> 0,05) a los de los controles. El análisis sensorial indicó que los panqués en los que se reemplazó 50% de la clara por ASP, gustaron tanto como los controles. Los panqués con un reemplazo del 100%, gustaron menos. La excelente calidad microbiológica de los panqués muestra las óptimas condiciones sanitarias durante la obtención de la ASP y su elaboració[email protected] effect of porcine serum albumin (PSA) as a substitute for egg white (EW) in chocolate cakes was examined. PSA was obtained by a lab-scaled method of Hydrophobic Interaction Chromatography. 50 and 100% of the evel of EW was replaced with PSA in cake formulation. All cakes had similar (P > 0.05) crumb L (25.7-26.2), a* (9.8-10.1) y b* (14.5-15.0) and crust: L (25.7-26.2), a* (9.8-10.1) y b* (14.5-15.0) color values. Texture (2.9 N) and volume (148.9 1.8 cm 3) of cakes with 50% PSA replacing EW were similar (P > 0.05) to those of the controls. Sensory analysis indicated that cakes replaced with 50% EW for ASP were as well liked as control cakes. The excellent microbiological quality of formulated cakes points out the optimal sanitary conditions in the PSA isolation and in the cake elaboration process

Chemical composition and antioxidant-prooxidant potential of a polyphenolic extract and a proanthocyanidin-rich fraction of apple skin

The apple is a food rich in diverse classes of polyphenols (PP), among which the proanthocyanidins (PCs), which are primarily concentrated in the skin, are one of the most abundant. These compounds are of considerable interest for their possible positive health effects because of their antioxidant properties. However, depending on the classes of PP present (chemical composition) and their relative concentrations in the apple skin, their antioxidant effects vary and some of their components can even generate prooxidant effects. This work determined the chemical composition and antioxidant-prooxidant potential of a polyphenolic extract (PPE) and a proanthocyanidin-rich fraction (PRF) of apple skin, along with the contribution of their most abundant individual compounds, based on their copper chelating ability, ease in reducing peroxidase-generated free radicals and TEAC (Trolox-Equivalent Antioxidant Capacity) assay. For this purpose, chromatographic and colorimetric methods were used. The majority compounds identified in PPE were flavan-3-ols (44.58%), flavonols (42.89%) and dihydrochalcones (11.60%). In PRF, we detected monomers and oligomers from dimers to heptamers, which were composed of 97% (−)-epicatechin and 3% (+)-catechin. The antioxidant potential was notably higher in PRF than in PPE. The (−)-epicatechin monomer and the procyanidin B2 dimer showed more ease in reducing peroxidase-generated free radicals compared to other compounds of the apple skin, whereas phloridzin dihydrochalcone produced prooxidant effects

Novel Synthesis of Core-Shell Silica Nanoparticles for the Capture of Low Molecular Weight Proteins and Peptides

Silica nanoparticles were functionalized with immobilized molecular bait, Cibacron Blue, and a porous polymeric bis-acrylamide shell. These nanoparticles represent a new alternative to capture low molecular weight (LMW) proteins/peptides, that might be potential biomarkers. Functionalized core-shell silica nanoparticles (FCSNP) presented a size distribution of 243.9 ± 11.6 nm and an estimated surface charge of −38.1 ± 0.9 mV. The successful attachment of compounds at every stage of synthesis was evidenced by ATR-FTIR. The capture of model peptides was determined by mass spectrometry, indicating that only the peptide with a long sequence of hydrophobic amino acids (alpha zein 34-mer) interacted with the molecular bait. FCSNP excluded the high molecular weight protein (HMW), BSA, and captured LMW proteins (myoglobin and aprotinin), as evidenced by SDS-PAGE. Functionalization of nanoparticles with Cibacron Blue was crucial to capture these molecules. FCSNP were stable after twelve months of storage and maintained a capacity of 3.1–3.4 µg/mg

Características de la germinación de Lippiapalmeri (Wats) proveniente de regiones silvestres del desierto de Altar, Sonora, México

There are several species of native and introduced Lippia, which are of great potential in arid areas of Northwest Mexico; these species have low germination percentage due to the hardness and / or seed dormancy. The aim of this study was to elucidate the effect of gibberellic acid on germination of seeds of wild Lippia palmeri. To do this, the seed was collected in two native sites (Puerto del Orégano and Santa Ana, Sonora). Three concentrations with gibberellic acid (GA3) (100, 200 and 300ppm), subjected to three times of soaking the seed (30, 60 and 120 min.) were tested and as a control distilled water. For each treatment 100 seeds were used by Petri dish in triplicate with a total of 72 Petri plates placed in an ambient of 27 °C and 80% relative humidity. For the concentration of 100 ppm in the three treatments soaking seed port oregano, showed a high percentage of germination (90, 100 and 100%); for treatments of 200 and 300 ppm the percentage of germinated seed was lower (80%). The seed of Santa Ana showed the highest percentage of germination (80%) obtained 300 ppm and 120 minute soak; the other treatments did not exceed 70% germination. It is concluded that Lippia palmeri require stimulated by giberalina to promote the enzymatic action inducing breakdown of reserve substances seed.Existen varias especies del género de Lippia nativas e introducidas, que son de gran potencial en zonas áridas del noroeste de México; estas especies presentan bajo porcentaje de germinación debido a la dureza y/o dormancia de la semilla. El objetivo del presente estudio consistió en dilucidar el efecto del ácido giberélico sobre la germinación de la semillas silvestre de Lippia palmeri. Para ello se recolectó la semilla en dos regiones nativas (Puerto del Orégano y Santa Ana, Sonora). Se probaron tres concentraciones con ácido giberélico (GA3) (100, 200 y 300 ppm, sometidas a tres tiempos de remojo de la semilla (30, 60 y 120 min.) y como control agua destilada. Para cada tratamiento se utilizaron 100 semillas por caja Petri por triplicado siendo un total de 72 cajas Petri colocadas a una temperatura ambiente de 27 °C y 80% de humedad relativa. Para la concentración de 100 ppm en los tres tratamientos de remojo la semilla de Puerto del Orégano, mostró un alto porcentaje de germinación (90, 100 y 100%), para los tratamientos de 200 y 300 ppm el porcentaje de semilla germinada fue menor (80%). La semilla de Santa Ana mostró el porcentaje más alto de germinación con (80%) obtenido a 300 ppm y 120 minutos en remojo, el resto de los tratamientos no superó el 70% de germinación. Se concluye que Lippia palmeri requieren ser estimuladas por la giberelina a fin de promover la acción enzimática que induce la ruptura de las sustancias de reserva de la semilla

Identification of Allergenic Proteins in Velvet Mesquite (Prosopis velutina) Pollen: An Immunoproteomics Approach

Velvet mesquite (Prosopis velutina) is a native legume of the southwestern United States and northwestern Mexico, contributing significantly to the desert ecosystem and playing key ecological roles. It is also an important cause of allergic respiratory disease widely distributed in the Sonoran, Chihuahuan, and Mojave Deserts. However, no allergens from velvet mesquite pollen have been identified to date. Pollen proteins were extracted and analyzed by one- and two-dimensional electrophoresis and immunoblotting using a pool of 11 sera from mesquite-sensitive patients as the primary antibody. IgE-recognized protein spots were identified by mass spectrometry and bioinformatics analysis. Twenty-four unique proteins, including proteins well known as pollen, food, airway, or contact allergens and four proteins not previously reported as pollen allergens, were identified. This is the first report on allergenic proteins in velvet mesquite pollen. These findings will contribute to the development of specific diagnosis and treatment of mesquite pollen allergy

Nanoproteomic Approach for Isolation and Identification of Potential Biomarkers in Human Urine from Adults with Normal Weight, Overweight and Obesity

In this work, previously synthesized and characterized core-shell silica nanoparticles (FCSNP) functionalized with immobilized molecular bait, Cibacron blue, and a porous polymeric bis-acrylamide shell were incubated with pooled urine samples from adult women or men with normal weight, overweight or obesity for the isolation of potential biomarkers. A total of 30 individuals (15 woman and 15 men) were included. FCSNP allowed the capture of a variety of low molecular weight (LMW) proteins as evidenced by mass spectrometry (MS) and the exclusion of high molecular weight (HMW) proteins (>34 kDa) as demonstrated by SDS-PAGE and 2D SDS-PAGE. A total of 36 proteins were successfully identified by MS and homology database searching against the Homo sapiens subset of the Swiss-Prot database. Identified proteins were grouped into different clusters according to their abundance patterns. Four proteins were found only in women and five only in men, whereas 27 proteins were in urine from both genders with different abundance patterns. Based on these results, this new approach represents an alternative tool for isolation and identification of urinary biomarkers