Metrics of the Biometrics: The Steady Growth of an Interdisciplinary Field

The word biometry or its derivative, biometrics, depicts the need for close interdisciplinary research among big data systems, mathematics, and statistical sciences. Reports headed with the word biometrics are constantly increasing. Below, the information provided by databases evidences the expansion and evolution from the original main biological topics to new research areas.Centro de Investigación de Proteínas Vegetale

Host-guest molecular interactions in vanillin/Hylon VII inclusion complexes

The interaction of 4-hydroxy-3-methoxybenzaldehyde (vanillin) and Hylon VII due to the formation of an inclusion complex is studied using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and circular dichroism (CD). The results confirm the close interaction among the different functional groups of vanillin and its host. In addition, a second case study was carried out with an amylose 1 from a different source (100% amylose [APT III]). ). As a result, remarkable differences were found in the vanillin complexation capability of this amylose, which is only shown in solution by circular dichroism spectroscopy studies through a clear Cotton effect. This finding confirms the value of using CD studies, which allow finding that, depending of the amylose source, inclusion complexes can be found only in solution, or both in solution and the coexisting precipitates, when this is shown using other techniques, such as X-ray diffraction (XRD) or differential scanning calorimetry (DSC). Moreover, solubility assays and complexation of both starches with iodine and subsequent absorption spectroscopy studies gives more information regarding the possible source of the starch encapsula- tion capability. Thus, Hylon VII shows higher capacity as vanillin encapsulant than APT III, showing the formation of inclusion complexes both in solution and solid phase, whereas APT III complexes are only perceivable in solution.Fil: Rodríguez, Silvio David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de Los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires; ArgentinaFil: Bernik, Delia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de Los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires; Argentin

Image texture analysis and gas sensor array studies applied to vanilla encapsulation by octenyl succinic anhydride starches

Native starch derivatization with octenyl succinic anhydride (OSA) is a chemical modification designed to enhance flavor microencapsulation performance. Hi Cap 100 and Capsul are two OSA starches derived from waxy maize base, which are especially suited for encapsulation processes. This work performs for the first time the encapsulation of vanilla extract with Capsul and Hi Cap 100 using both spray and freeze drying procedures. The encapsulation efficiency was studied correlating the starch texture with the aroma retention. Texture analysis was accomplished by means of grey level co-occurrence matrix feature extraction (GLCM), yielding image parameters that clearly differ in function of the type of starch and the drying method used for the encapsulation of the flavor. In parallel, the data recorded with a gas sensor array (e-nose) and analyzed by unsupervised multivariate methods allowed to follow up the evolution of the aroma through the whole process. The joint analysis of the GLCM and sensor array recorded data indicates that Capsul shows a higher capacity for vanilla encapsulation than Hi Cap 100. In addition, the obtained converging information from GLCM and e-nose data clearly indicates that particle texture and aroma encapsulation are connected.Fil: Rodríguez, Silvio David. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Wilderjans, Tom F.. Faculty of Psychology and Educational Sciences. Methodology of Educational Sciences Research Group; BélgicaFil: Sosa, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Orgánica; ArgentinaFil: Bernik, Delia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Characterization of the fruit proteolytic system of Bromelia serra Griseb. (Bromeliaceae) and its application in bioactive peptides release

A crude extract with proteolytic activity was prepared from edible fruits of Bromelia serra, containing cysteine peptidases with molecular masses between 24.1 and 25.9 kDa. The extract presented an optimal pH range of 6.03‒9.05, retained more than 80% of activity after thermal pre-treatments at 23, 37, and 45°C (120 min), but it was rapidly inactivated after 10 min at 75°C. These proteases were employed to hydrolyze soybean proteins, bovine casein and bovine whey, achieving degrees of hydrolysis of 18.3 ± 0.6, 29.1 ± 0.7, and 12.6 ± 0.9% (55°C, 180 min), respectively. The casein 180 min-hydrolysate (55°C) presented the maximum value of antioxidant activity (2.89 ± 0.12 mg/mL Trolox), and the whey protein 180 min-hydrolysate (55°C) showed the highest percentage of angiotensin-converting enzyme inhibition (91.9 ± 1.2%). This low-cost enzymatic preparation would be promising for the food industry because it requires mild working conditions and yields hydrolysates with biological activities useful as ingredients for functional food. Practical application: Proteolytic enzymes are employed in the food industry in a wide variety of processes since they modify the properties of proteins causing beneficial effects such as improvement digestibility, diminution of allergenicity, and release of bioactive peptides. Fruits from Bromelia serra possess cysteine peptidases that could be used in food biotechnology because they are capable to hydrolyze soybean and milk proteins by mild working conditions and to provoke the release of bioactive peptides. These hydrolysates containing antioxidative and ACE-inhibitor activities would be useful as ingredients for functional foods or as nutraceuticals, which are nowadays two products highly required by consumers.Fil: Salese, Lucía. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación de Proteínas Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Liggieri, Constanza Silvina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación de Proteínas Vegetales; ArgentinaFil: Bernik, Delia Leticia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación de Proteínas Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Bruno, Mariela Anahí. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación de Proteínas Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

CARACTERIZACIÓN DE PROTEASAS DE BROMELIAS AUTÓCTONAS Y SU APLICACIÓN EN LA PRODUCCIÓN DE BIOPÉPTIDOS A PARTIR DE PROTEÍNAS ALIMENTARIAS

Numerosas especies vegetales poseen grandes cantidades de proteasas que podrían ser empleadas en biotecnología alimentaria. Nuestro objetivo es obtener, purificar y caracterizar peptidasas de bromelias autóctonas (Bromeliaceae) y emplearlas en la producción de péptidos bioactivos a partir de proteínas alimentarias, con el fin de ser evaluados como posibles componentes en alimentos funcionales y nutracéuticos. Se obtuvieron diferentes extractos crudos (ECs) a partir de frutos inmaduros y ejes de las infrutescencias de Bromelia hieronymi, a partir de frutos de B. serra en diferente estado de madurez o por el empleo de diferentes partes de las bayas y, a partir de hojas de Deinacanthon urbanianum (=B. urbaniana). Los ECs de fruto de B. hieronymi fueron los más activos. El EC de hoja de D. urbanianum presentó baja actividad caseinolítica (AC), sin embargo, muestra al zimograma una banda muy activa de pI alcalino. Respecto a los ECs de B. serra, se seleccionó un extracto de frutos de maduración intermedia por sus valores de AC, con el objetivo de caracterizar y determinar las condiciones óptimas de trabajo. Se determinó que las proteasas de B. serra son de tipo cisteínico, sus masas moleculares están comprendidas entre 23,3-26,6 kDa, y presentan un rango de pH óptimo de 6,3-9,0. Se observó estabilidad térmica por preincubación a 23, 37 y 45 ºC, e inactivación luego de 10 min de tratamiento a 75 ºC o de 2 min a 100 ºC. La mayor actividad esterásica se obtuvo sobre el sustrato N-α-carbobenzoxi-p-nitrofenil éster de L-Ala. Mediante purificación parcial con acetona y etanol se observó que, con cuatro volúmenes de ambos solventes, se recupera más del 90% de AC respecto del EC. Al menos 4 bandas proteicas fueron observadas al IEF (pIs: 8,4-<3,5), siendo la región alcalina la más activa. Se emplearon extractos de B. serra y B. hieronymi para hidrolizar proteínas de lactosuero, caseína y proteínas de soja, a 45 y 55 ºC. En todos los casos se observó una degradación progresiva de los tres sustratos y se obtuvieron mayores porcentajes de grado de hidrólisis en los hidrolizados de caseína de 55 ºC. Los hidrolizados de lactosuero presentaron los valores más altos de inhibición de la ECA. Por otra parte, se determinó la actividad antioxidante mediante dos variantes del método del ABTS (original y “quencher”), mostrando los mayores valores con el método quencher a 55 ºC para los hidrolizados de caseína. Las actividades biológicas fueron más elevadas en los hidrolizados de B. hieronymi por lo que fueron seleccionados para su posterior fraccionamiento por exclusión molecular. Se diseñó un protocolo para encapsular hidrolizados de lactosuero con actividad inhibitoria de la ECA caracterizado por MALDI-TOF. Empleando almidón de mandioca y mediante un procedimiento a bajas temperaturas se generan estructuras resistentes, con el fin de que los péptidos encapsulados no se degraden en la primera porción del tracto gastrointestinal

Bromide counterion as a spectroscopic sensor at the interface of cetyltrimethylammonium micelles

The strong UV absorption of the bromide in aqueous solution undergoes a remarkable red shift of more than 10 nm induced by the addition of the salts that constitute a saline buffer. The maximum absorption wavelength of the bromide is displaced from approximately 194 nm in ultrapure water to wavelengths above 200 nm, depending on the composition of the solution. The bromide spectrum as counterion of the cetyltrimethylammonium in the surfactant CTAB also shows sensitivity to the aggregation behavior of the tensioactive, being able to detect intermolecular interactions even at concentrations lower than the critical micelle concentration. And, when the micelles are assembled, the bromide absorption detects the interfacial rearrangements caused by the incorporation of ions. To know more about those interfacial features, the pyrene molecular probe was used, taking advantage of the extensive knowledge of its spectroscopy. Pyrene verifies the existence of changes in the interfacial organization which confirm that the sensitivity of the bromide spectrum is based on the ability of the ion to detect its microenvironment, and therefore reaffirms that its absorption spectrumcan be used as a local sensor. The presentwork encourages the use of bromide as a sensor ion in the UV region between 190 and 210 nm, which would avoid the introduction of external molecular probes that could disturb the system.Centro de Investigación de Proteínas Vegetale

Interaction of an acid protease with positively charged phosphatidylcholine bilayers

Positively charged bilayers composed of phosphatidylcholine (PC) and stearylamine (SA) in a 4:1 ratio reduce the effectiveness of a protease from Mucor miehei to produce milk clotting. This is related to the adsorption of the protein, which at pH 7 is negatively charged, by electrostatic forces. However, an increase in SA, which increases the membrane packing parallel to the increase in the surface charge density, counteracts the protein membrane association. This is in agreement with the fact that the protease can also adsorb on pure phosphadylcholine bilayers in the fluid state but not in the gel state. In addition, the presence of phosphatidylethanolamine also inhibits protease adsorption. It is concluded that the protein affects the membrane interface of fluid PC membranes because the electrostatic charges pull the protein to the bilayer interface causing changes in hydration and area per molecule. The adsorption is only at the level of the polar head groups since no effects were observed in the hydrocarbon core region.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Change in the micellar aggregation number or in the size distribution?: a dynamic fluorescence quenching study of aqueous cetyltrimethylammonium chloride

Aqueous solutions of cetyltrimethylammonium chloride were studied by means of dynamic fluorescence quenching measurements to get information on the micellar aggregation number and size polydispersity as a function of surfactant concentration. The global analysis of multiple decay curves provided estimates with improved accuracy and precision and indicated a reduced polydispersity upon increasing surfactant concentration. As the quenching rate slows with increasing surfactant concentration it is concluded that there is a micellar growth, but that this growth preferably increases the aggregation number for the smaller aggregates in the initially polydisperse solutions.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Silicon based materials for drug delivery devices and implants

This patent review focuses on silicon based materials for drug delivery systems and implant devices devoted to medical applications. The article describes some representative examples of the most depictive silicon based compounds associated with drug release formulations and tissue engineering biomaterials. Ranging from inorganic to organic and hybrid inorganic-organic silicon compounds, the paper referrers to patents describing inventions which make use of the best properties of silicon dioxide, silica aerogel and xerogel, silicon bioactive materials, silicones and ormosils, pointing out the usefulness of each kind of compound within the invention embodiment.Fil: Bernik, Delia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Tracking the sex pheromone of codling moth against a background of host volatiles with an electronic nose

Mating disruption is now widely used in apple growing regions where control of codling moth is difficult due to insecticide resistance. This strategy comprises the slow release of pheromone from controlled delivery dispensers placed on the crop field with the aim to attract and/or confuse males impeding mating. The success of the technique strongly depends on maintaining an adequate pheromone concentration in the air within the crop. At present, monitoring of the sexual confusion efficiency is done by hand using lures and traps and carrying out a weekly evaluation of the trapped insects, which involves human resources and consumes considerable time and effort. This article describes the use of an electronic nose capable of detecting and discriminating low amounts of codling moth pheromone (codlemone) immersed in a background odour of plants and fruit volatiles. Laboratory results obtained indicate the feasibility of using a trained electronic nose for tracking in real-time aerial concentration levels of codlemone against a background of common apple host volatiles. Continuous field monitoring can potentially be achieved by combining the electronic nose with automated robotic navigation and remote transference of data.Fil: Negri, Ricardo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; ArgentinaFil: Bernik, Delia Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentin