Synthesis of Pyrodextrins and Enzymatically Resistant Maltodextrins from Makal (Xanthosoma yucatenensis) Starch.

Research background: Enzymatically resistant maltodextrins (ERM) are a resistant starch type 4, synthesized from native starch. They are obtained by the sequential application of two processes: pyrodextrinization, which produces pyrodextrins, and enzymatic hydrolysis, which produces ERM. In these processes atypical bonds are formed that confer pyrodextrins and ERM similar properties to dietary fiber, such as resistance to digestion. The aim of this work is to determine and evaluate some physicochemical properties of pyrodextrins and ERM obtained from native starch isolated from makal (Xanthosoma yucatanense) tubers. Experimental approach: Pyrodextrinization and complementary hydrolysis were conducted using factorial designs. For pyrodextrinization, factors and their levels were (m(starch):V(HCl))=80:1 and 160:1 (c(HCl)=2.2 M), temperature 90 and 110 °C and reaction time 1 and 3 h, and for CH, α-amylase per pyrodextrin volume fractions 0.5 and 1 µL/mL and reaction time 10 and 30 min. The physicochemical profile included determination of resistant starch content, estimation of color change (ΔE), microscopy and determination of dextrose equivalents (DE). Results and conclusions: According to the factorial design, the best treatment conditions for pyrodextrinization were: (m(starch):V(HCl))=160:1, 90 °C and 3 h, since they resulted in the highest resistant starch content (84.73 %) and the lowest ΔE (3.742). Due to the low DE (13.89 %), increased amount of resistant starch (90.73 %) and low ΔE (4.24) in the resulting ERM, complementary hydrolysis with α-amylase per pyrodextrin volume fraction 0.5 µL/mL and hydrolysis time 10 min was selected as the best treatment. Novelty and scientific contribution: The results show that the pyrodextrins and ERM obtained from makal can be used as ingredients for the development of functional foods, due to their high content of indigestible material and low degree of browning.

Development of Low Glycemic Index Pancakes Formulated with Canary Seed (Phalaris Canariensis) Flour.

Consumers prefer food products that, in addition to nutritional properties, also have effects beneficial to health. Non-conventional food plants such as canary seed (Phalaris canariensis) constitute an alternative in the food industry due to nutritional properties, chemical, and bioactive potential. The aim of this research was to develop pancake formulations with the inclusion of canary seed flour to evaluate their proximate composition, overall score, taste and texture sensory acceptability, and glycemic index. Pancakes based on whole-wheat flour mixed with canary seed flour were developed at four substitution levels (control 0, 10, 30, and 50%). The formulations exhibited attractive nutritional properties, mainly due to the levels of protein (~ 8.7%), minerals (~ 5.1%), and total dietary fiber (4.7-5.9%). The overall score and taste showed a statistical difference (p < 0.05) between the formulations. The flours with 10 and 30% showed high sensory acceptability with scores of 6.22 and 6.67 respect to 7-point hedonic scale, between the categories "I like it" and "I like it a lot". All formulations presented a low glycemic index (34-39%) that was significantly influenced (p < 0.05) as the level of substitution increased. The findings represent a new approach to the use of canary seed in the development of healthy food products.

Films properties of QPM corn starch with Delonix regia seed galactomannan as an edible coating material.

Plant-based polysaccharides are considered a good alternative for obtaining edible films and coatings. In this research the objective was to determine the physicochemical characteristics of corn starch obtained from QPM Sac-Beh (SBCS) and Delonix regia galactomannan (DRG) and use them to produce films. Films were elaborated from 1 %(w/v) film-forming solutions (FFS) with SBCS:DRG 1:0, 1:1, and 0:1 ratio. Some films were prepared with glycerol 0.4 %(w/v) and vanillin 0.1 %(w/v). SBCS and DRG were characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and differential scanning calorimetry. SBCS presented low crystallinity which agrees with a low gelatinization ΔH observed. The SBCS:DRG 1:0 FFS without glycerol did not form films; however, DRG addition allows film formation. It was also found that glycerol addition reduced tensile strength to 10.3 MPa, from 41.3 MPa. The lowest water vapor permeability was found in films with 1:1 SBCS:DRG and 0.1 %(w/v) vanillin. This formulation was used to coat D'Anjou pears. This coating conserved the pears' color for 24 days while the control ones started to get a brown color on day 6. Based on the results obtained, FFS elaborated with 1:1 SBCS:DRG and 0.1 %(w/v) vanillin had potential use as edible film material for coating on climacteric fruits preservation.

[Evaluation of the hypoglycemic effect of a peptide fraction of chia seeds (Salvia hispánica L.) in male Wistar rats induced with alloxan]. / Evaluación del efecto hipoglucemiante de una fracción peptídica de las semillas de chía (Salvia hispanica L.) en ratas macho Wistar inducidas con aloxano.

INTRODUCTION: Introduction: diabetes research with peptides from foods has been conducted in animal experiments to be later applied to humans. Objective: the main purpose of this work was to evaluate in rats the hypoglycemic effect of a peptide fraction of chia seeds derived by enzymatic hydrolysis. Materials and methods: from chia flour a protein-rich fraction was obtained, which was hydrolyzed with pepsin-pancreatin system enzymes to yield a peptide fraction (> 10 kDa) by ultrafiltration. Five rat groups (one normoglycemic and four diabetized with alloxan) were used. A sucrose tolerance curve was performed, providing the disaccharide before measurement. Blood was taken from the tip of the tail at 0 (before sugar), 30, 60, 90, and 120 minutes. Results: the protein content of chia flour was 49.51 %. The peptide fraction (> 10 kDa) had 91 % of protein. A dose of 50 mg/kg showed in rats a tendency to decrease blood glucose within the first hour, but no significance was found between the target and the doses evaluated. There was no decrease in glucose absorption vs. the reference drug. At 120 min postprandial, no differences were found between doses, water, and acarbose, showing a return to the baseline status. The tolerance curve in diabetic rats was opposite to that of acarbose, so there was no relationship between the drug's mechanism of action and this analyzed effect. Conclusion: the peptide fraction of chia of > 10 kDa showed no hypoglycemic effect at the single dose that was administered.

INTRODUCCIÓN: Introducción: se han realizado investigaciones sobre la diabetes con péptidos de diferentes fuentes alimentarias en animales experimentales para aplicarse después en los seres humanos. Objetivo: la finalidad de este trabajo fue evaluar en ratas el efecto hipoglucemiante de una fracción peptídica de chía obtenida por hidrólisis enzimática. Materiales y métodos: de la harina de chía se obtuvo una fracción rica en proteína que fue hidrolizada con pepsina-pancreatina, generándose una fracción peptídica (> 10 kDa) por ultrafiltración. Se utilizaron cinco grupos de ratas (uno de normoglucémicas y cuatro de diabetizadas con aloxano). Se realizó una curva de tolerancia a la sacarosa, proporcionándoles el disacárido antes de la medición. La sangre se tomó de la punta de la cola a los 0, 30, 60, 90 y 120 minutos. Resultados: el contenido proteico de la harina fue del 49,51 %. La fracción peptídica (> 10 kDa) presentó un 91 % de proteína; de esta se suministró una dosis de 50 mg/kg que demostró una tendencia a la disminución de la glucosa sanguínea en la primera hora, aunque no se encontró significancia entre el blanco y las dosis evaluadas. No hubo disminución de la absorción de glucosa frente al fármaco de referencia. A los 120 min del periodo postprandial no se encontraron diferencias entre las dosis, el blanco y la acarbosa, lo que denota un retorno al estado basal. Los valores en las ratas diabetizadas fueron opuestos a los de la acarbosa, por lo que no existió relación entre el mecanismo de acción del fármaco con el efecto analizado. Conclusión: las fracciones peptídicas de chía de > 10 kDa no presentaron efecto hipoglucemiante con la dosis única suministrada.

Actividad antioxidante y quelante de sistemas hidrocoloides mixtos formados por hidrolizados proteicos de Phaseolus vulgaris endurecido y goma modificada de flamboyán (Delonix regia) / Antioxidant and metal-chelating activities of mixed hydrocolloid systems formed by hard-to-cook Phaseolus vulgaris protein hydrolysates and flamboyant (Delonix regia) modified gum

Las proteínas y polisacáridos con frecuencia son utilizados simultáneamente en la industria de alimentos. Las interacciones entre ambos biopolímeros juegan un papel importante en la estructura y estabilidad de muchos alimentos procesados ya que pueden resultar en un sistema con propiedades bioactivas diferentes como ocurre en el caso de las funcionales. Objetivo. Evaluar los cambios en la capacidad antioxidante de un sistema hidrocoloide mixto formado por un hidrolizado enzimático proteico de frijol endurecido (P. vulgaris) y goma modificada de flamboyán (Delonix regia) (SHM). Materiales y métodos. El estudio se hizo entre febrero-octubre, 2014, en Mérida, México. Se modificó enzimáticamente el concentrado proteico de P. vulgaris con Pepsina-Pancreatina® y la goma extraída del flamboyán mediante carboximetilación, preparando dispersiones al 1% de cada uno de los biopolímeros, determinado la fluorescencia intrínseca de Trp (FIT) como indicador de la interacción entre ambos biopolímeros y la actividad antioxidante y quelante del sistema resultante. Resultados. Se obtuvo un hidrolizado proteico extensivo con 28,8% de grado de hidrólisis y una goma de flamboyán con grado de sustitución de 0,91. La mayor interacción entre ambos biopolímeros, se obtuvo empleando una relación 5:1 del SHM a pH 4 de acuerdo con el valor de FIT. Conclusiones. Los sistemas hidrocoloides mixtos preparados con hidrolizado extensivo de las proteínas Phaseolus vulgaris y goma modificada de flamboyán presentaron un incremento en la actividad antioxidante, respecto del hidrolizado dependiendo del mecanismo de oxidación, así como de las condiciones de pH en que se encuentra el sistema y la interacción entre ambos componentes(AU)

Proteins and polysaccharides are frequently used simultaneously in the food industry. The interactions between both biopolymers play an important role in the structure and stability of many processed foods since they can result in a system with different bioactive properties as in the case of functional ones. Objective. Evaluate the changes in the antioxidant capacity of mixed hydrocolloid system formed by a hard to cook bean (P. vulgaris) protein enzymatic hydrolyzate and modified flamboyant gum (Delonix regia) (SHM). Materials and methods. The study was conducted from February to October 2014 in Merida, Mexico. For this, the protein concentrate of P. vulgaris was treated with Pepsin-Pancreatin® and the gum extracted from the flamboyant were modified enzymatically by carboxymethylation, preparing 1% dispersions of each of the biopolymers, determining the intrinsic Trp fluorescence (FIT) as an indicator of the interaction between both biopolymers and the antioxidant and chelating activity of the resulting system. Results. The main results indicated that an extensive protein hydrolyzate with 28.8% degree of hydrolysis and a flamboyant gum with a substitution degree of 0.91 were obtained. The greatest interaction between both biopolymers was obtained using a 5:1 ratio of SHM to pH 4 according to the FIT value. Conclusions. The mixed hydrocolloid systems prepared with extensive hydrolyzate of the hard to cook P. vulgaris and modified flamboyant gum proteins showed an increase in antioxidant activity, compared to the hydrolyzate depending on the oxidation mechanism, as well as the pH conditions used and interaction between both component(AU)

[Anticancer effect of modified banana (Musa cavendish AAA) starch in rats with 1.2-dimethylhydrazine]. / Efecto anticancerígeno del almidón modificado de banano (Musa cavendish AAA) en ratas con 1,2-dimetilhidrazina.

INTRODUCTION: Introduction: resistant starch (RS) is not completely digested in the human intestine but is fermented in the colon; intestinal pH decreases as short-chain fatty acids are produced. This is beneficial for health, and for preventing and treating rectal colon cancer. Pyrodextrinization and enzymatic hydrolysis are modifications to native starch (NS) that may increase the amount of RS. Objective: the objective of this project was to evaluate the effects of M. cavendish AAA native and both chemically and enzymatically modified starches on tumor markers in rats. Methods: modifications (chemical and enzymatic) were made to M. cavendish AAA NS, and were evaluated in rats with 1,2-DMH. Male Sprague Dawley rats (25) were used, divided into five experimental groups: PC, NC, NS, PI, and ERM. During 4 weeks they received the experimental diet assigned to each group. The PC, NS, PI and ERM groups received 2 weekly s.c. (subcutaneous) injections of 1,2-DMH (40 mg/kg) (third and fourth week). In feces, pH, ß-glucuronidase enzyme, and short-chain fatty acids were evaluated, and a histopathological study was performed of the intestine to detect microscopic lesions. Results: the activity of ß-glucuronidase decreased (p < 0.05) for NS, PI and ERM vs. PC. The highest proportion of butyric acid was observed in the NS (p < 0.05) vs. NC group. Sixty percent of enteritides were severe in grade in the PC group, and 40 % in the experimental groups. Conclusions: native starch granules resisted pyrodextrinization, but treatment with α-amylase broke the structure of the pyrodextrin granule. According to the treatments given to the rats, as the amount of RS present in the diet increases (NS), the neoplastic cells do not advance beyond the basement membrane, suggesting a possible cell-protective or anticancer effect.

INTRODUCCIÓN: Introducción: el almidón resistente (AR) no se digiere completamente en el intestino humano sino que se fermenta en colon; disminuye el pH intestinal, ya que se producen ácidos grasos de cadena corta, interviniendo de manera benéfica en el tratamiento preventivo y curativo del cáncer de colon rectal. La pirodextrinización y la hidrólisis enzimática son modificaciones al almidón nativo (AN) que pueden incrementar la cantidad de AR. Objetivo: el objetivo de este proyecto fue evaluar los efectos del almidón nativo de M. cavendish AAA y de los almidones modificados química y enzimáticamente sobre diversos marcadores tumorales en ratas. Métodos: se realizaron modificaciones (química y enzimática) del AN del banano M. cavendish AAA y se evaluaron en ratas tratadas con 1,2-DMH. Se utilizaron 25 ratas Sprague Dawley machos divididas en cinco grupos experimentales: CP, CN, AN, PI y MER. Durante 4 semanas recibieron la dieta experimental asignada a cada grupo. Los grupos CP, AN, PI y MER recibieron 2 inyecciones s.c. (subcutáneas) semanales de 1,2-DMH (40 mg/kg) (semanas 3 y 4). En las heces se evaluaron el pH, la enzima ß-glucuronidasa y los ácidos grasos de cadena corta, y se realizó un estudio histopatológico del ciego y el colon para detectar lesiones microscópicas. Resultados: la actividad de ß-glucuronidasa disminuyó (p < 0,05) para los grupos AN, PI y MER en comparación con el CP. La mayor proporción de ácido butírico se observó en el AN (p < 0,05) frente al CN. El 60 % de las enteritis fueron de grado severo en el CP, mientras que en los grupos experimentales fueron de 40 %. Conclusiones: los gránulos de almidón nativo resistieron la pirodextrinización pero el tratamiento con α-amilasa rompió la estructura del gránulo de pirodextrina. De acuerdo a los tratamientos suministrados a las ratas, conforme mayor es la cantidad de AR presente en la dieta (AN), las células neoplásicas no avanzan más allá de la membrana basal, sugiriendo un posible efecto protector o anticancerígeno celular.

[Wound healing effect of peptide fractions from Phaseolus lunatus proteins by enzymatic hydrolysis]. / Efecto cicatrizante de fracciones peptídicas derivadas de la hidrólisis enzimática de proteínas de Phaseolus lunatus.

INTRODUCTION: Introduction: protein hydrolysates from plant seeds are a source of bioactive peptides. However, no studies on wound healing activity have been published. Objective: to evaluate the healing effect in vivo (in mice) of enzymatic hydrolysates of Phaseolus lunatus using pepsin, pancreatin, the pepsin-pancreatin sequential system and the peptide fractions of each hydrolysate, greater and less than 10 kDa. Methods: the wound healing tests were performed on mice divided in groups of five mice per treatment. The wounds were monitored with a stereomicroscope (Stemi™ DV4), measuring the area with photographs on days 0, 1, 3, 6, 8 and 10. The time elapsed from the formation of each wound to 80% reduction of its area was calculated. Finally, the fraction or hydrolysate amino acid residues that showed greater wound healing activity were identified by HPLC chromatography (Agilent 1100 series). Results: the wounds treated with pancreatin hydrolysate (PanH) and with its fraction greater than 10 kDa (PanF1) showed 80% of healing at 2.86 and 3.03 days, respectively, while this occurred using the control at 5.04 days. These represented the greatest wound healing activity of all the treatments. The analysis of the amino acids determined an important presence of hydrophobic and basic residues that contributed significantly to wound healing. Conclusion: the PanH hydrolysate, obtained from the protein concentrate of Phaseolus lunatus, and its fraction greater than 10 kDa could be used to encourage wound healing.

INTRODUCCIÓN: Introducción: los hidrolizados de proteína de semillas de plantas son una fuente de péptidos bioactivos. Sin embargo, no se han publicado estudios sobre la actividad cicatrizante de heridas. Objetivo: evaluar el efecto cicatrizante in vivo (en ratones) de hidrolizados enzimáticos de Phaseolus lunatus empleando pepsina, pancreatina, el sistema secuencial pepsina-pancreatina y las fracciones peptídicas de cada hidrolizado, mayores y menores de 10 kDa. Métodos: las pruebas de cicatrización se realizaron en ratones divididos en grupos de cinco ratones por tratamiento. Las heridas se observaron en un estereomicroscopio (Stemi™ DV4), midiendo el área con fotografías los días 0, 1, 3, 6, 8 y 10. Se calculó el tiempo transcurrido desde la formación de cada herida hasta el 80% de reducción de su área. Por último, los residuos aminoacídicos de la fracción o hidrolizado que mostró mayor actividad cicatrizante fueron identificados por cromatografía HPLC (Agilent 1100 series). Resultados: las heridas tratadas con hidrolizado de pancreatina (PanH) y su fracción mayor de 10 kDa (PanF1) mostraron un avance del 80% de cicatrización a los 2,86 y 3,03 días, respectivamente, mientras que con el control fueron 5,04 días. Estos representaron la mayor actividad cicatrizante de todos los tratamientos. El análisis de aminoácidos determinó una presencia importante de residuos hidrofóbicos y básicos que contribuyeron de manera notable a la cicatrización de heridas. Conclusión: el hidrolizado PanH, obtenido del concentrado proteico de Phaseolus lunatus, y su fracción mayor de 10 kDa podrían ser usados para favorecer la cicatrización de heridas.

Angiotensin-Converting Enzyme Inhibition In Vitro by Protein Hydrolysates and Peptide Fractions from Mojarra of Nile Tilapia (Oreochromis niloticus) Skeleton.

Mojarra of Nile tilapia (Oreochromis niloticus) skeleton was used as protein source for the preparation of protein hydrolysates and peptide fractions with angiotensin-converting enzyme (ACE) inhibitory activity. The flour presented a content of 34.92% protein and a brightness (luminosity, L*) of 82.29. Protein hydrolysates were obtained from the protein-rich flour with the enzymes Flavourzyme® and Alcalase® reaching degree of hydrolysis (%DH) of 52% and 67% at 100 min of reaction, respectively. Both hydrolysates showed low-molecular-weight (MW) peptides estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The hydrolysates obtained with Flavourzyme at 60 min and at 80 min with Alcalase showed greater ACE inhibitory activity with IC50 values of 0.238 and 0.344 mg/mL, respectively. The peptide fraction A (MW >10 kDa) with Flavourzyme and fraction B (MW = 10-5 kDa) with Alcalase obtained by ultrafiltration of hydrolysates with higher DH presented IC50 of 0.728 and 0.354 mg/mL, respectively, whereas peptide fraction C (MW = 5-3 kDa) with both enzymes hydrolysates with greater ACE inhibitory activity showed IC50 values of 0.470 and 0.634 mg/mL. The components obtained in this study could be used as functional ingredients in the design and development of functional foods.

Effect of extraction method and specie on the content of bioactive compounds and antioxidant activity of pumpkin oil from Yucatan, Mexico.

In this study, the effect of the extraction method (mechanical pressing, MP and organic solvent, OS) and the specie (Cucurbita argyrosperma Huber, CA; and Cucurbita moschata Duchesne, CM) on the content of bioactive compounds and antioxidant activity of oil from pumpkin of Yucatan, Mexico was investigated. Between the two extraction methods, the oil extracted by MP obtained the highest values for total phenolic compounds (TPC), total carotenoids, squalene, quercetin, ß-carotene, fucosterol, stigmasterol and antioxidant activity (DPPH, ABTS and reducing power). Between the two species, the CM oil extracted with MP or OS exhibited the highest values for carotenoids, sterols and antioxidant activity (DPPH and ABTS). Thus, it can be concluded that the method and specie affect the composition of bioactive compounds and antioxidant activity of the pumpkin oil. This information is useful for the extraction of pumpkin oil with a higher content of compounds, of interest for the industry.

Protein hydrolysates and ultrafiltered < 1 KDa fractions from Phaseolus lunatus, Phaseolus vulgaris and Mucuna pruriens exhibit antihyperglycemic activity, intestinal glucose absorption and α-glucosidase inhibition with no acute toxicity in rodents.

BACKGROUND: Protein hydrolysates from food plants, such as legumes, have emerged as a new alternative to treat hyperglycemia, an important risk factor contributing to the development of type 2 diabetes mellitus (T2DM) and its complications. The aim of this work was to assess the antihyperglycemic activity and inhibition of α-glucosidase, and intestinal glucose absorption, and acute toxicity of total hydrolysates and < 1 kDa fractions from Phaseolus lunatus L., Phaseolus vulgaris L., and Mucuna pruriens (L.) DC., obtained by hydrolysis with Alcalase®-Flavourzyme® or pepsine-pancreatin enzymatic systems. RESULTS: In vivo results showed that three of six total hydrolysates and four of six < 1 kDa fractions suppressed starch-induced postprandial hyperglycemia (ED50 range between 1.4 and 93 mg kg-1 ). In vitro, total hydrolysates and fractions, particularly from M. pruriens, inhibited carbohydrate intestinal absorption (from 19.2 to 40%), and α-glucosidase activity (IC50 from 0.86 to 75 mg mL-1 ). Finally, none of the hydrolysates and fractions tested did not show any signs of toxicity (LD50 > 5000 mg kg-1 ). CONCLUSION: These results suggest that hydrolysates and < 1 kDa fractions from P. lunatus, P. vulgaris and M. pruriens are suitable candidates to treat or prevent T2DM. © 2018 Society of Chemical Industry.

[Inhibitory effect of peptide fractions derivatives from chia (Salvia hispanica) hydrolysis against α-amylase and α-glucosidase enzymes]. / Efecto inhibitorio de fracciones peptídicas derivadas de la hidrólisis de semillas de chía (Salvia hispanica) sobre las enzimas α-amilasa y α-glucosidasa.

INTRODUCTION: biopeptides are amino acid sequences with biological functions about metabolism and carbohydrates absorption. OBJECTIVE: the aim of this study was the evaluation of the inhibitory effect of peptide fractions derivatives of the hydrolysis of Salvia hispanica against α-amylase and α-glucosidase enzymes to know their activity on the carbohydrates metabolism. MATERIAL AND METHODS: the fraction rich in protein was hydrolyzed by two enzymatic systems: Alcalase®-Flavourzyme® and pepsin-pancreatine. The grade of hydrolysis was determined for the samples. The hydrolyzed samples were centrifuged and the soluble portion was ultra-filtered using different cut membranes. The content of protein was determined for each fraction. An in vitro analysis was made, measuring the percentage of inhibition of the Salvia hispanica fractions against α-amylase and α-glucosidase. RESULTS: the enzymatic system showing the highest grade of hydrolysis (63.53%) was pepsin-pancreatine. From the ultrafiltration, five peptide fractions were obtained: 10 kDa, 5-10 kDa, 3-5 kDa, 1-3 kDa and 1 kDa. The highest protein content was for these fractions: 10 kDa and 5-10 kDa, (0.90 and 0.93 mg/ml, respectively) for pepsin-pancreatine. The inhibition percentages obtained were 85.61% and 79.19% for the 10 kDa and 5-10 kDa fractions, respectively, for the α-amylase enzyme. With respect to the α-glucosidase enzyme, the highest inhibition was for the 10 kDa fraction, with 96.91%. CONCLUSION: the peptide fractions obtained from the chia may increase the natural sources for the preparation of functional foods important for the diabetic patient's diet.

Introducción: los biopéptidos son secuencias aminoacídicas que pueden ejercer funciones biológicas sobre el metabolismo y la absorción de carbohidratos.Objetivo: la finalidad de este estudio fue evaluar el efecto inhibitorio de fracciones peptídicas derivadas de la hidrólisis de Salvia hispanica sobre las enzimas α-amilasa y α-glucosidasa, para comprobar su actividad en el metabolismo glucídico. Material y métodos: se obtuvo una fracción rica en proteína, la cual fue hidrolizada mediante dos sistemas enzimáticos: Alcalasa®-Flavourzima® y pepsina-pancreatina. A las muestras obtenidas se les determinó el grado de hidrólisis. El hidrolizado fue centrifugado y la porción soluble fue ultrafiltrada, utilizando diferentes membranas de corte. A cada fracción se le determinó el contenido de proteína. Se realizó un análisis in vitro midiendo el porcentaje de inhibición de las fracciones de Salvia hispanica sobre α-amilasa y α-glucosidasa.Resultados: el sistema enzimático que presentó el mayor grado de hidrólisis (63,53%) fue la pepsina-pancreatina. De la ultrafiltración se obtuvieron cinco fracciones peptídicas: > 10 kDa, 5-10 kDa, 3-5 kDa, 1-3 kDa y < 1 kDa. El mayor contenido de proteína lo presentaron las fracciones de > 10 kDa y 5-10 kDa (0,90 y 0,93 mg/ml, respectivamente) para pepsina-pancreatina. Los porcentajes de inhibición obtenidos fueron de 85,61% y 79,19% para las fracciones de > 10 kDa y 5-10 kDa, respectivamente para la enzima α-amilasa. Para la enzima α-glucosidasa, el mayor porcentaje de inhibición fue para la fracción de > 10 kDa, con 96,91%.Conclusión: los péptidos obtenidos de la chía podrían incrementar las fuentes naturales para la elaboración de alimentos funcionales importantes para la dieta de pacientes diabéticos.

Effects of modified banana (Musa cavendish)starch on glycemic control and blood pressure in rats with high sucrose diet.

INTRODUCTION: insulin resistance (IR) is the preliminary stage of diseases such as diabetes and hypertension. These diseases can be controlled through medication, yet the consumption of functional foods (FF) may be one complementary treatment option. Ingredients for these FF could be the pyrodextrin and enzymatically resistant maltodextrin (ERM) obtained from the native starch (NS) of M. cavendishin this study. OBJECTIVE: to evaluate the effects of modified banana starch on glycemic control and blood pressure in rats with high sucrose diet (HSD). METHODS: we utilized 25 male Wistar rats 20 of which received a HSD and five were fed a normal diet and purified water (PW) for 12 weeks. At the end of week 8, the rats fed a HSD were divided into four groups: positive control (PC), native starch (NS), pyrodextrin (PI), and enzymatically resistant maltodextrin (ERM). The negative control (NC) comprised the five rats fed PW. We evaluated the glucose tolerance test, blood pressure (BP), insulin levels, total cholesterol (TC), high-density lipoproteins (HDL), and triglycerides. RESULTS: differential scanning calorimetry and scanning electron microscopy of the modified starches demonstrated that the pyroconversion treatment did not visibly affect the NS granules, while ERM was modified by the action of α-amylase. Starch treatments reduced glucose, insulin, HOMA-IR, and BP in comparison with PC (p < 0.05). Glucose AUC (0-120 min) was also decreased after starch treatments with respect to PC (p < 0.05). CONCLUSION: NS and its modified products exerted beneficial effects on glycemic control, lipid metabolism, and BP in obese rats fed a HSD. Although the modified starches presented lower resistance to digestion than NS, their expected properties were maintained.

In vitro renin-angiotensin system inhibition and in vivo antihypertensive activity of peptide fractions from lima bean (Phaseolus lunatus L.).

BACKGROUND: The renin-angiotensin system is key in the physiopathology of arterial hypertension because it converts angiotensin I, via angiotensin I-converting enzyme (ACE), into angiotensin II. In vitro analyses were done of the ACE-inhibitory and renin-inhibitory activities of peptide fractions isolated by enzymatic hydrolysis of lima bean (Phaseolus lunatus) protein. Antihypertensive activity was confirmed in vivo using a rat model. RESULTS: Lima bean protein was hydrolyzed with one of two sequential enzymatic systems (pepsin-pancreatin or Alcalase®-Flavourzyme®). Ultrafiltration of the hydrolysates produced fractions of different molecular weights. The >3 kDa fraction of the pepsin-pancreatin hydrolysate had the highest ACE-inhibitory activity (60.15%, IC50: 172.62 µg mL-1 ), while the >3 KDa fraction of the Alcalase®-Flavourzyme® hydrolysate had the highest in vitro renin-inhibitory activity. A weak correlation (r = 0.44) was found between ACE-inhibitory and renin-inhibitory activities. When tested in vivo, the latter fraction lowered systolic blood pressure by 64% and diastolic blood pressure by 51%. CONCLUSION: Peptide fractions from lima bean Phaseolus lunatus protein hydrolysates exhibit both in vitro and in vivo antihypertensive activity. Bioactive peptides from lima bean have potential applications as ingredients in functional foods. © 2017 Society of Chemical Industry.

Biofunctional properties of bioactive peptide fractions from protein isolates of moringa seed (Moringa oleifera).

Moringa oleifera (Moringaceae) is a specie of significant importance because of its multiple nutraceutical properties, that has led to increase in its consumption. The seeds contain a high percentage of protein (37.48%). However, little is known about the bioactive properties of these proteins and peptides, especially those generated by enzymatic hydrolysis. The objective of this study was to evaluate the biofunctional properties of total hydrolysates (TH) and peptide fractions from protein isolates of moringa seeds. Isoelectric protein isolates were prepared and TH were obtained by digestion with trypsin, chymotrypsin and pepsin-trypsin for 2.5 and 5 h. TH were fractioned by ultrafiltration (UF) with a 10 kDa membrane to generate the peptide fractions. In all treatments, the antioxidant capacity was significantly higher in peptide fractions > 10 kDa with 5 h of hydrolysis. The results showed that the fraction > 10 kDa of pepsin-trypsin digested for 5 h presented a better Angiotensin Converting Enzyme inhibition (ACE-I) activity with an IC50 of 0.224 µg/µl. Also, antidiabetic activity was enhanced in pepsin-trypsin treatment with 5 h of hydrolysis showing an IC50 of 0.123 µg/µl. Finally, this study showed that hydrolysates of moringa seed proteins had excellent in vitro nutraceutical potential.

Some Nutritional Characteristics of Enzymatically Resistant Maltodextrin from Cassava (Manihot esculenta Crantz) Starch.

Cassava (Manihot esculenta Crantz) native starch was treated with pyroconversion and enzymatic hydrolysis to produce a pyrodextrin and an enzyme-resistant maltodextrin. Some nutritional characteristics were quantified for both compounds. Pyroconversion was done using a 160:1 (p/v) starch:HCl ratio, 90 °C temperature and 3 h reaction time. The resulting pyrodextrin contained 46.21% indigestible starch and 78.86% dietary fiber. Thermostable α-amylase (0.01%) was used to hydrolyze the pyrodextrin at 95 °C for 5 min. The resulting resistant maltodextrin contained 24.45% dextrose equivalents, 56.06% indigestible starch and 86.62% dietary fiber. Compared to the cassava native starch, the pyrodextrin exhibited 56% solubility at room temperature and the resistant maltodextrin 100%. The glycemic index value for the resistant maltodextrin was 59% in healthy persons. Its high indigestible starch and dietary fiber contents, as well as its complete solubility, make the resistant maltodextrin a promising ingredient for raising dietary fiber content in a wide range of foods, especially in drinks, dairy products, creams and soups.

Evaluation of Hypotensive and Antihypertensive Effects of Velvet Bean (Mucuna pruriens L.) Hydrolysates.

Hypertension could cause significant worldwide health problems that affect 15-20% of all adults; according to National Health and Nutrition Examination Survey, about 29% of the adult population in the United States are hypertensive. Recent research has shown that peptides derived from the hydrolysis of food proteins can decrease blood pressure. This study was carried out to evaluate the hypotensive and antihypertensive potential of Mucuna pruriens protein hydrolysates in in vitro and in vivo models. M. pruriens protein concentrate was prepared by wet fractionation and enzymatically hydrolyzed using Alcalase®, Flavourzyme®, and the sequential system Alcalase-Flavourzyme at different times (5-120 min). The biological potential was measured in vitro based on the IC50 value as well as in vivo effect, measuring the systolic (SBP) and diastolic (DBP) blood pressure in normotensive and antihypertensive Wistar-Kyoto rats by the tail-cuff method. Hydrolysis of M. pruriens protein concentrates with commercial enzymes generated extensive hydrolysates with angiotensin-converting enzyme (ACE-I) inhibitory activity (IC50: 0.589-0.993 mg/mL) and hypotensive (SBP: 0.6-47.43%, DBP: 1.94-43.47%) and antihypertensive (SBP: 8.84-27.29% DBP: 16.1-29.37%) effect. These results indicate that Mucuna pruriens protein hydrolysate (MPPH) could be used as a functional ingredient to prevent blood pressure increase.

Effects of plant intraspecific diversity across three trophic levels: Underlying mechanisms and plant traits.

PREMISE OF STUDY: Although there is increasing recognition of the effects of plant intraspecific diversity on consumers, the mechanisms by which such effects cascade-up to higher trophic levels remain elusive. METHODS: We evaluated the effects of plant (lima bean, Phaseolus lunatus) intraspecific diversity on a suite of insect herbivores (leaf-chewers, aphids, and seed-eating beetles) and their third trophic-level associates (parasitoids and aphid-tending ants). We established plots of three plants, classified as monocultures of one population source or polycultures with mixtures of three of the four population sources (N = 16 plots per level of diversity). Within each plot, plants were individually placed in pots and canopy contact was prevented, therefore eliminating diversity effects on consumers arising from changes in plant traits due to plant physical interactions. KEY RESULTS: Plant diversity reduced damage by leaf-chewers as well as aphid abundance, and the latter effect in turn reduced ant abundance. In contrast, plant diversity increased the abundance of seed-eating beetles, but did not influence their associated parasitoids. There were no effects of diversity on seed traits potentially associated with seed predation, suggesting that differences in early season herbivory between monocultures and polycultures (a likely mechanism of diversity effects on plants since plant interactions were prevented) did not drive concomitant changes in plant traits. CONCLUSIONS: This study emphasizes that effects of plant intraspecific diversity on consumers are contingent upon differences in associate responses within and among higher trophic levels and suggests possible mechanisms by which such effects propagate up this food web.

Alcaloides y polifenoles del cacao, mecanismos que regulan su biosíntesis y sus implicaciones en el sabor y aroma / Cacao alkaloids and polyphenols: Mechanisms that regulate their biosynthesis and its implications on the taste and aroma

El sabor y aroma de los granos de cacao (Theobroma cacao L.) fueron las principales razones que promovieron su domesticación y uso alimentario por los pueblos precolombinos de Mesoamérica. Incluso hoy día, la calidad sensorial determina la clasificación entre cacaos finos y a granel. Muchos compuestos químicos de las almendras son responsables de la calidad sensorial, pero sobresalen los polifenoles y los alcaloides, compuestos que de manera directa inciden en el sabor y palatabilidad de las almendras y de manera indirecta sobre los precursores de aroma. Los alcaloides están asociados con el amargor. Su concentración está relacionada con la variedad y se modifica con el procesamiento. Los polifenoles son responsables, junto con otras moléculas de la astringencia (poco deseable en chocolates), pero también de propiedades antioxidantes deseables por los consumidores. En esta revisión se abordan aspectos de la biosíntesis de estas importantes moléculas en las almendras de cacao, de las implicaciones en el sabor y aroma, así como los cambios que ocurren durante el procesamiento de las mismas(AU)

The flavor and aroma of cacao (Theobroma cacao) beans were the main reasons that promoted its domestication and food-use by pre-Columbian peoples of Mesoamerica. Polyphenols and alkaloids are compounds that directly affect the flavor of the cocoa beans and indirectly on the flavor precursors. The alkaloids are associated with bitterness; its concentration is related to the cultivar and its modifying through the processing. Polyphenols molecules are responsible together with other molecules of the astringency (not desirable in chocolate), but also are responsible for antioxidant properties, very desirable by consumers. This review focuses on aspects of the biosynthesis of these important molecules in cocoa beans as well as implications in taste and flavor. The changes of these molecules that occur during processing are also approached(AU)

Evaluation of the Antihyperglycemic Effect of Minor Steviol Glycosides in Normoglycemic and Induced-Diabetic Wistar Rats.

Steviol glycosides are a family of compounds found in Stevia rebaudiana Bertoni that are responsible for sweetness capacity. The antihyperglycemic effect of the two major steviol glycosides, Rebaudioside A and Stevioside, has been studied and it has been found that despite having the same common structure, only Stevioside exerts an antihyperglycemic effect. Although other steviol derivatives are found in smaller amounts (minor steviol glycosides) in S. rebaudiana, whether or not they possess antihyperglycemic activity has not been evaluated. The aim of this study was to evaluate the antihyperglycemic effect of minor steviol glycosides in normoglycemic and diabetic (streptozotocin/nicotinamide) Wistar rats. Rats were subjected to an intraperitoneal glucose tolerance test (IPGTT) both before and after chronic treatment (28 days). After 6 h of fasting, IPGTT was conducted in pentobarbital-anesthetized rats using 1 g/kg of glucose plus 20 mg/kg of the minor glycoside (Dulcoside A, Rebaudioside B, C, D, or Steviolbioside) or control treatment (distilled water, glibenclamide, or metformin); the blood of the tip of the tail was collected at time 0, 15, 30, 60, and 120 min.; and blood glucose was measured, and its net area under the curve (AUCnet) was calculated. After 28-day chronic oral administration, IPGTT was again performed. Differences were considered significant at P < .05 by one-way ANOVA. Acute intraperitoneal or chronic oral administration of 20 mg/kg of minor steviol glycosides had no antihyperglycemic effect in normoglycemic or induced-diabetic Wistar rats. Considering the dose tested, it is unlikely that these glycosides have an effect on glucose in diabetic or normoglycemic humans.

Bioactive Properties of Phaseolus lunatus (Lima Bean) and Vigna unguiculata (Cowpea) Hydrolyzates Incorporated into Pasta. Residual Activity after Pasta Cooking.

The aims of the study were to study the inclusion of P. lunatus (PLH) and V. unguiculata (VUH) protein hydrolyzates with bioactive properties into a pasta-extruded product and determine residual activity after extrusion or pasta cooking. Both protein hydrolyzates showed angiotensin-converting enzyme inhibition (ACEI) and antioxidant activity (TEAC). PLH showed higher ACEI but lower TEAC than VUH (97.19 ± 0.23 vs. 91.95 ± 0.29 % and 244.7 ± 3.4 vs. 293.7 ± 3.3 µmol Trolox/g, respectively). They were included at 5 or 10 % into wheat pasta. Control pasta had the lowest ACEI activity or TEAC (22.01 ± 0.76 % or 14.14 ± 1.28 µmol Trolox/g, respectively). Higher activity remained in pasta with PLH than VUH after extrusion, and higher the level of addition, higher the ACEI was. Pasta had practically the same ACEI activity after cooking, thus active compounds were not lost by temperature or lixiviation. Regarding TEAC, higher activity remained in pasta with 10 % VUH (31.84 ± 0.17 µmol Trolox/g). Other samples with hydrolyzates had the same activity. After cooking, pasta with hydrolyzates had higher TEAC values than control, but these were not modified by the level of incorporation. Moreover, the profile changed because pasta with PLH had the highest TEAC values (21.39 ± 0.01 and 20.34 ± 0.15 for 5 or 10 % hydrolyzates, respectively). Cooking decreased this activity (~ 20 %), for all samples. Although a certain loss of antioxidant activity was observed, pasta could be a good vehicle for bioactive compounds becoming a functional food.