Phenolic Content and Bioactivity as Geographical Classifiers of Propolis from Stingless Bees in Southeastern Mexico.

Propolis collected by stingless bees is a valuable biocultural resource and a source of bioactive compounds. Methodologies to establish both the geographic origin and the potential pharmacological activity of propolis of stingless bees are required to regulate their sustainable use. The aim of this study was to classify Melipona beecheii propolis according to its phenolic compound content and potential pharmacological activity, using in vitro assays and statistical methodologies of multivariate analysis, hierarchical cluster analysis, and principal component analysis. Propolis samples were collected from seven states in southeastern Mexico. Total phenolic content and flavonoids were determined spectrophotometrically, and antioxidant, anti-inflammatory, and antimicrobial activities were evaluated. Both total phenolic content and flavonoids, and in vitro bioactivity potential of propolis extracts showed significant variations. Multivariate analysis, hierarchical cluster analysis, and principal component analysis enabled us to distinguish and classify propolis produced by M. beecheii according to similarity in terms of total phenolic content, in vitro bioactivity potential, and geographical origin. This strategy could be used to establish regulations for sustainable use, marketing, and industrial applications.

Antioxidant and antihypertensive activity of Gouda cheese at different stages of ripening.

In Mexico, local ripened cheeses such as Chihuahua, Ranchero, and Cotija are produced, being consumed in great quantities together with imported cheeses. Proteolysis that takes place during ripening generates bioactive peptides; in this way the cheese acquires potential as a functional food. The ripening process of Gouda cheese was studied based on its bromatological and sensorial properties, bioactivity, and peptide profile. Ripened cheese met bromatological standard parameters and showed higher overall acceptability. After 90 days, bioactivity reached maximum values for radical scavenging (6.6%), ferric reducing power (11.2%), metal chelating effect (49%), and angiotensin I-converting enzyme inhibitory activity (66.2%). Eight peptides were identified, four from αS1-casein, f(1-9, 1-13, 1-14, and 25-36), and four from ß-casein, f(11-28, 60-63, 193-209, and 197-205). Ripening of Gouda cheese results in a product with functional potential due to the presence of peptides with biological activity. Additionally, the methodology proposed in this work could be used by the dairy industry to monitor the manufacturing process and ripening of other types of cheeses.

A Survey of the Mosquito Species in Maxcanu, Yucatan, Mexico.

A survey was carried out to identify the mosquitoes inhabiting human premises in the rural locality of Maxcanú, Yucatán, Mexico. Using the Centers for Disease Control and Prevention backpack aspirators, simple random sampling was carried out inside of 101 homes during the November 2013 rainy season. A total of 1,492 specimens were collected. Three subfamilies (Anophelinae, Culicinae, and Toxorhynchitinae) and 5 species were identified: Anopheles albimanus, Aedes aegypti, Culex interrogator, Limatus durhamii, and Toxorhynchites theobaldi. The most abundant species was Cx. interrogator (74%) followed by Ae. aegypti (25%). The Chao 1 and Bootstrap species richness estimator indicated that it was possible to collect 90% of the expected species. This is the 1st time that the presence of An. albimanus, Cx. interrogator, Li. durhamii, and Tx. theobaldi has been recorded in Maxcanú.

Encapsulation of vegetable oils as source of omega-3 fatty acids for enriched functional foods.

Polyunsaturated omega-3 fatty acids (PUFAs), a functional component present in vegetable oils, are generally recognized as being beneficial to health. Omega-3 PUFAs are rich in double bonds and unsaturated in nature; this attribute makes them highly susceptible to lipid oxidation and unfit for incorporation into long shelf life foods. The microencapsulation of oils in a polymeric matrix (mainly polysaccharides) offers the possibility of controlled release of the lipophilic functional ingredient and can be useful for the supplementation of foods with PUFAs. The present paper provides a literature review of different vegetable sources of omega-3 fatty acids, the functional effects of omega-3 fatty acids, different microencapsulation methods that can possibly be used for the encapsulation of oils, the properties of vegetable oil microcapsules, the effect of encapsulation on oxidation stability and fatty acid composition of vegetable oils, and the incorporation of long-chain omega-3 polyunsaturated fatty acids in foods.

Potential Therapeutic Applications of Mucuna pruriens Peptide Fractions Purified by High-Performance Liquid Chromatography as Angiotensin-Converting Enzyme Inhibitors, Antioxidants, Antithrombotic and Hypocholesterolemic Agents.

A Mucuna pruriens protein concentrate was hydrolyzed with a digestive (pepsin-pancreatin) enzymatic system. The soluble portion of the hydrolysate was fractionated by ultrafiltration and the ultrafiltered peptide fraction (PF) with lower molecular weight was purified by reversed-phase high-performance liquid chromatography. The PF obtained were evaluated by testing the biological activity in vitro. Fractions showed that the ability to inhibit the angiotensin-converting enzyme had IC50 values that ranged from 2.7 to 6.2 µg/mL. Trolox equivalent antioxidant capacity values ranged from 132.20 to 507.43 mM/mg. The inhibition of human platelet aggregation ranged from 1.59% to 11.11%, and the inhibition of cholesterol micellar solubility ranged from 0.24% to 0.47%. Hydrophobicity, size, and amino acid sequence could be factors in determining the biological activity of peptides contained in fractions. This is the first report that M. pruriens peptides act as antihypertensives, antioxidants, and inhibitors for human platelet aggregation and cholesterol micellar solubility in vitro.

Electrophoresis characterisation of protein as a method to establish the entomological origin of stingless bee honeys.

Increasing production of stingless-bee honey and the prospect of broader marker for natural and organic products indicate the need to establish parameters to determinate the entomological origin and authenticity of honey. In this research, honeys of Apis mellifera, Melipona beecheii and Trigona spp. were collected in Yucatan, Mexico. Stingless-bee honeys contained more water and less total sugars and reducing sugars. SDS-PAGE patterns show distinctive bands for each kind of honey. The SDS-PAGE pattern of A. mellifera proteins honey showed three bands with molecular weights between 10.2 and 74.8kDa, there were five proteins bands in M. beecheii honey with molecular weights between 6.1 and 97.0kDa and nine for Trigona spp. proteins between 9.3 and 86.7kDa. Conventional physicochemical parameters along with electrophoresis profiles of stingless-bee honeys proteins could be an alternative for determination of entomological origin.

Antioxidant capacity of leaf extracts from two Stevia rebaudiana Bertoni varieties adapted to cultivation in Mexico.

The recent introduction of the cultivation of Stevia rebaudiana Bertoni in Mexico has gained interest for its potential use as a non-caloric sweetener, but some other properties of this plant require studies. Extracts from two varieties of S. rebaudiana Bertoni adapted to cultivation in Mexico were screened for their content of some phytochemicals and antioxidant properties. Total pigments, total phenolic and flavonoids contents of the extracts ranged between 17.7-24.3 mg/g, 28.7-28.4 mg/g, and 39.3-36.7 mg/g, respectively. The variety "Criolla" exhibited higher contents of pigments and flavonoids. Trolox equivalent antioxidant capacity ranged between 618.5-623.7 mM/mg and DPPH decolorization assay ranged between 86.4-84.3%, no significant differences were observed between varieties. Inhibition of ß-carotene bleaching ranged between 62.3-77.9%, with higher activity in the variety "Criolla". Reducing power ranged between 85.2-86% and the chelating activity ranged between 57.3-59.4% for Cu²âº and between 52.2-54.4% for Fe²âº, no significant differences were observed between varieties. In conclusion, the results of this study showed that polar compounds obtained during the extraction like chlorophylls, carotenoids, phenolic compounds and flavonoids contribute to the antioxidative activity measured. The leaves of S. rebaudiana Bertoni could be used not only as a source of non-caloric sweeteners but also naturally occurring antioxidants.

La reciente introducción del cultivo de Stevia rebaudiana Bertoni en México ha ganado interés debido a su potencial uso como fuente de edulcorantes no calóricos, pero otras propiedades de esta planta aun requieren de estudios. Extractos de hojas de dos variedades de S. rebaudiana Bertoni adaptadas al cultivo en México fueron evaluados en cuanto a su contenido de algunos fitoquímicos y sus propiedades antioxidantes. El contenido de pigmentos, fenoles totales y flavonoides en los extractos, osciló entre 17.7-24.3 mg/g, 28.7-28.4 mg/g, y 39.3-36.7 mg/g, respectivamente. La variedad "Criolla" exhibió los mayores contenidos de pigmentos y flavonoides. La capacidad antioxidante equivalente de Trolox osciló entre 618.5-623.7 mM/mg y el ensayo de decoloración del radical DPPH osciló entre 86.4-84.3%, no observándose diferencias significativas entre ambas variedades. La inhibición de la decoloración del -caroteno osciló entre 62.3-77.9%, siendo mayor en la variedad "Criolla". El poder reductor osciló entre 85.2-86%, las capacidades quelantes de cobre y hierro oscilaron entre 57.3-59.4% y 52.2-54.4%, respectivamente, no observándose diferencias significativas entre ambas variedades. En conclusión, los resultados de este estudio demuestran que los compuestos de naturaleza polar obtenidos durante la extracción, tales como pigmentos clorofílicos, carotenoides, compuestos fenólicos y flavonoides contribuyen a la actividad antioxidante. Las hojas de S. rebaudiana Bertoni podrían ser empleadas no solo como fuente de edulcorantes no calóricos, sino también como fuente de antioxidantes de origen natural.

Encapsulation of Phaseolus lunatus Protein Hydrolysate with Angiotensin-Converting Enzyme Inhibitory Activity.

The objective of recent research has been to seek alternative therapeutic treatments; for this reason, the use of protein hydrolysates from diverse sources has been studied. A way to guarantee that these treatments reach the site of action is through protection with covers, such as microcapsules. Therefore, proteins from the legume Phaseolus lunatus were hydrolyzed and encapsulated with a blend of Delonix regia carboxymethylated gum/sodium alginate (50 : 50 w/w). Hydrolysis release conditions in a simulated gastrointestinal system were obtained using CaCl2 concentrations as the main factor, indicating that lower CaCl2 concentrations lead to an increased hydrolysis release. Beads obtained with 1.0 mM of CaCl2 exhibited a better hydrolysate release rate under intestinal simulated conditions and the proteins maintained an IC50 of 2.9 mg/mL. Capsules obtained with the blend of Delonix regia carboxymethylated gum/sodium alginate would be used for the controlled delivery of hydrolysates with potential use as nutraceutical or therapeutic agents.

Amputación interescapulo-toráxica para sarcoma de la extremidad superior del humerus / Interescapulo-thoracic amputation for sarcoma of the upper extremity of humerus

El 6 de agosto de 1909 ocupó la cama numero 32 en mi servicio de Clínica Quirúrgica Jorge Tuyo, natural de Funza, de 50años de edad, de profesión agricultor y sin antecedentes patológicos de importancia. El principio de su enfermedad actual la hace remontar á siete meses antes, en que comenzó a sentir dolores en el hombro derecho, dolores que al principio poco marcados, fueron aumentando de intensidad, y se hacían intolerables después del fuerte trabajo que estaba obligado á ejecutar durante el día. Al poco tiempo de la aparición de los dolores notó la tumefacción en el hombro y la dificultad de los movimientos en el miembro correspondiente. Desde hace algunas semanas los dolores han sido continuos, la impotencia funcional del brazo absoluta, el enflaquecimiento considerable, y últimamente el edema ha invadido el antebrazo y la mano. El examen del enfermo el día de su entrada al Hospital hace ver un hombre profundamente enflaquecido y su aspecto revela grandes sufrimientos. Al descubrirlo, á primera vista se aprecia el contraste que forma la enorme tumefacción del hombro derecho con el aspecto enflaquecido y anguloso del izquierdo. El tumor, del tamaño de una cabeza de adulto, ocupa todo el muñón del hombro, pero mientras que hacia atrás es un poco aplastado, hacia delante forma un relieve esférico, y el examen más detenido hace ver que la tumefacción ha invadido hacia arriba parte del hueco supraclavicular, hacia delante gran parte de la región pectoral y hacia abajo la axila.