David Betancur Ancona

Angiotensin-I converting enzyme inhibitory and antioxidant activities of peptide fractions extracted by ultrafiltration of cowpea Vigna unguiculata hydrolysates

BACKGROUND Enzymatic proteolysis of food proteins is used to produce peptide fractions with the potential to act as physiological modulators. Fractionation of these proteins by ultrafiltration results in fractions rich in small peptides with the potential to act as functional food ingredients. The present study investigated the angiotensin-I converting enzyme (ACE-I) inhibitory and antioxidant activities for hydrolysates produced by hydrolyzing Vigna unguiculata protein extract as well as ultrafiltered peptide fractions from these hydrolysates. RESULTS Alcalase(®), Flavourzyme(®) and pepsin-pancreatin were used to produce extensively hydrolyzed V. unguiculata protein extract. Degree of hydrolysis (DH) differed between the enzymatic systems and ranged from 35.7% to 58.8%. Fractionation increased in vitro biological activities in the peptide fractions, with IC(50) (hydrolysate concentration in µg protein mL(-1) required to produce 50% ACE inhibition) value ranges of 24.3-123 (Alcalase hydrolysate, AH), 0.04-170.6 (Flavourzyme hydrolysate; FH) and 44.7-112 (pepsin-pancreatin hydrolysate, PPH) µg mL(-1), and TEAC (Trolox equivalent antioxidant coefficient) value ranges of 303.2-1457 (AH), 357.4-10 211 (FH) and 267.1-2830.4 (PPH) mmol L(-1) mg(-1) protein. CONCLUSION The results indicate the possibility of obtaining bioactive peptides from V. unguiculata proteins by means of a controlled protein hydrolysis using Alcalase(®), Flavourzyme(®) and pepsin-pancreatin. The V. unguiculata protein hydrolysates and their corresponding ultrafiltered peptide fractions might be utilized for physiologically functional foods with antihypertensive and antioxidant activities.

Angiotensin I-Converting Enzyme Inhibitory Peptides of Chia (Salvia hispanica) Produced by Enzymatic Hydrolysis

Synthetic angiotensin I-converting enzyme (ACE-I) inhibitors can have undesirable side effects, while natural inhibitors have no side effects and are potential nutraceuticals. A protein-rich fraction from chia (Salvia hispanica L.) seed was hydrolyzed with an Alcalase-Flavourzyme sequential system and the hydrolysate ultrafiltered through four molecular weight cut-off membranes (1 kDa, 3 kDa, 5 kDa, and 10 kDa). ACE-I inhibitory activity was quantified in the hydrolysate and ultrafiltered fractions. The hydrolysate was extensive (DH = 51.64%) and had 58.46% ACE-inhibitory activity. Inhibition ranged from 53.84% to 69.31% in the five ultrafiltered fractions and was highest in the <1 kDa fraction (69.31%). This fractions amino acid composition was identified and then it was purified by gel filtration chromatography and ACE-I inhibition measured in the purified fractions. Amino acid composition suggested that hydrophobic residues contributed substantially to chia peptide ACE-I inhibitory strength, probably by blocking angiotensin II production. Inhibitory activity ranged from 48.41% to 62.58% in the purified fractions, but fraction F1 (1.5–2.5 kDa) exhibited the highest inhibition (IC50 = 3.97 μg/mL; 427–455 mL elution volume). The results point out the possibility of obtaining bioactive peptides from chia proteins by means of a controlled protein hydrolysis using Alcalase-Flavourzyme sequentional system.Synthetic angiotensin I-converting enzyme (ACE-I) inhibitors can have undesirable side effects, while natural inhibitors have no side effects and are potential nutraceuticals. A protein-rich fraction from chia (Salvia hispanica L.) seed was hydrolyzed with an Alcalase-Flavourzyme sequential system and the hydrolysate ultrafiltered through four molecular weight cut-off membranes (1 kDa, 3 kDa, 5 kDa, and 10 kDa). ACE-I inhibitory activity was quantified in the hydrolysate and ultrafiltered fractions. The hydrolysate was extensive (DH = 51.64%) and had 58.46% ACE-inhibitory activity. Inhibition ranged from 53.84% to 69.31% in the five ultrafiltered fractions and was highest in the <1 kDa fraction (69.31%). This fraction’s amino acid composition was identified and then it was purified by gel filtration chromatography and ACE-I inhibition measured in the purified fractions. Amino acid composition suggested that hydrophobic residues contributed substantially to chia peptide ACE-I inhibitory strength, probably by blocking angiotensin II production. Inhibitory activity ranged from 48.41% to 62.58% in the purified fractions, but fraction F1 (1.5–2.5 kDa) exhibited the highest inhibition (IC50 = 3.97 μg/mL; 427–455 mL elution volume). The results point out the possibility of obtaining bioactive peptides from chia proteins by means of a controlled protein hydrolysis using Alcalase-Flavourzyme sequentional system.

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.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.

The hypolipidemic effect and antithrombotic activity of Mucuna pruriens protein hydrolysates

Hydrolysates and peptide fractions (PF) obtained from M. pruriens protein concentrates with commercial and digestive enzymatic systems were studied for their hypolipidemic and antithrombotic activities. Hydrolysates obtained with Pepsin–Pancreatin (PP) and their peptide fractions inhibited cholesterol micellar solubility with a maximum value of 1.83% in PP. Wistar rats were used to evaluate the hypolipidemic effect of hydrolysates and PF. The higher reductions of cholesterol and triglyceride levels were exhibited by PP and both peptide fractions 10 kDa from both hydrolysates showed the maximum antithrombotic activity with values of 33.33% for PF > 10 kDa from AF and 31.72% for PF > 10 kDa from PP. The results suggest that M. pruriens bioactive peptides with the hypolipidemic effect and antithrombotic activity might be utilized as nutraceuticals.

Coccoloba uvifera (L.) (Polygonaceae) Fruit: Phytochemical Screening and Potential Antioxidant Activity

The flora of Latin America attracts gaining interest as it provides a plethora of still unexplored or underutilized fruits that can contribute to human well-being due to their nutritional value and their content of bioactive compounds. Antioxidant compounds are now of considerable interest due to their effect of preventing or delaying aging and their apparent involvement in prevention of numerous human diseases, including cancer, atherosclerosis, Alzheimer’s disease, inflammation, and rheumatoid arthritis. In this work, the fruit of Coccoloba uvifera (L.) was investigated for their in vitro antioxidant capacity using two assays based on reactions with a relatively stable single reagent radical (Trolox equivalent antioxidant capacity, TEAC; and DPPH free radical scavenging assay, DPPH), two assays based on chelating of metallic cations, and one based on the reduction of oxidized species. The TEAC value on ABTS radical, DPPH scavenging activity, ion chelation, and reducing power were found to be 897.6 μM of Trolox/100 g of sample, 22.8% of DPPH free radical scavenging, 11.3% of Cu2

COMPUESTOS BIOACTIVOS DE LA DIETA CON POTENCIAL EN LA PREVENCIÓN DE PATOLOGÍAS RELACIONADAS CON SOBREPESO Y OBESIDAD; PÉPTIDOS BIOLÓGICAMENTE ACTIVOS

Overweight and obesity are risk factors for noncommunicable diseases such as cardiovascular diseases, diabetes and some types of cancer. The risk for these noncommunicable diseases increase with the increase in body mass index. Dietary proteins are known to carry a wide range of nutritional, functional and biological properties. Nutritionally, the proteins are a source of energy and amino acids, which are essential for growth and maintenance. Functionally, the proteins contribute to the physicochemical and sensory properties of various protein-rich foods. Furthermore, many dietary proteins possess specific biological properties which make these components potential ingredients of functional or health-promoting foods. Many of these properties are attributed to physiologically active peptides encrypted in protein molecules. This paper reviews antihypertensive, antithrombotic, hypocholesterolemic, hypoglycemic and hypolipidemic peptides originating from different sources and hydrolysis of proteins.

ESTUDIOS DE INHIBICIÓN IN VITRO DE LA ENZIMA CONVERTIDORA DE ANGIOTENSINA-I, EFECTOS HIPOTENSOR Y ANTIHIPERTENSIVO DE FRACCIONES PEPTÍDICAS DE V. UNGUICULATA

Inhibition of angiotensin-converting enzyme I (ACE-I) in vitro and in vivo from peptide fractions by enzymatic hydrolysis of the Vigna unguiculata protein concentrate was evaluated. Hydrolysis was done with Pepsin-Pancreatin and Flavourzima in two separate systems. The resulting hidrolysates were ultrafiltrated to obtain fractions with different molecular weight. The fractions with better inhibition Flavourzima were size > 1 kDa (> 1 kDa-F) and < 1 kDa (< 1 kDa-F), with an IC50 of 1222.84 and 1098.6 μg/ml respectively. Pepsin-Pancreatin fraction.

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 patients diet.

Substituição do açúcar com extratos de S. rebaudiana sobre as propriedades físico-químicas e sensoriais de sorvete de morango

Sorvete e um produto cuja formulacao requer quantidades consideraveis de acucar. Alem de proporcionar o sabor, o acucar contribui para as propriedades fisico-quimicas do sorvete, mas o seu consumo em grandes quantidades esta relacionada com as doencas cronicas, como diabetes e obesidade. Por essa razao, a industria alimenticia buscou formular produtos com adocantes para manter as propriedades fisico-quimicas e sensoriais do produto original. Stevia rebaudiana e uma planta que contem naturalmente glicosideos sem calorias com alta capacidade adocante, cujo consumo e considerado seguro. Portanto, o objetivo deste estudo foi avaliar o efeito da substituicao do acucar por diferentes niveis de extratos de S. rebaudiana Morita II e Criolla, sobre as propriedades fisico-quimicas e sensoriais do sorvete de morango. Usando um modelo experimental de fator 2x2, um total de 4 formulacoes foram preparadas com 2 niveis de concentracao de extrato aquoso de Stevia rebaudiana (5 ou 8%) e a variedade de Stevia (Morita II ou Criolla). Os produtos processados foram submetidos a analises proximais e fisico-quimicas, e avaliacao sensorial foi realizada para tres deles. A analise do sorvete de morango teve uma variacao estatisticamente significativa (P 0,05) entre as formulacoes avaliadas e a pontuacao de todos os produtos estava acima do ponto de indiferenca, indicando que todos eles podem ter um potencial comercial.Ice cream is a product whose formulation requires considerable amounts of sugar. In addition to providing flavor, sugar contributes to the physicochemical characteristics of ice cream but its consumption in large quantities is related to chronic diseases such as diabetes and obesity. For this reason, the food industry seeks to formulate products with sweeteners that preserve the physicochemical and sensory characteristics of the original product. Stevia rebaudiana is a plant that naturally contains glycosides with no calories and high sweetening capacity and it is considered safe for consumption. Therefore the aim of this research was to evaluate the effect of replacing sugar with different levels of extracts of S. rebaudiana Morita II and Criolla, on the physicochemical and sensory properties of strawberry ice cream. Using a 2x2 factorial experimental design, a total of 4 formulations were prepared with two levels of concentration of the aqueous extract of Stevia rebaudiana (5 or 8%) and the variety of S. rebaudiana (Morita II or Criolla). Proximate composition, physicochemical properties and sensory evaluation were determined in processed products. The proximate analysis of strawberry ice cream varied significantly (P<0.05) depending of variety and level used on the formulation. The viscosities of all ice cream mixes were decreasing as the shear rate was increased, indicating a pseudoplastic behavior. The sensory analysis showed differences (P<0.05) among the formulations tested, however the score of all products were above the indifference point, suggesting that all of these formulations may have a commercial potential.

Tannins and Saponins in Two Tropical Legumes and Measurement of their Biological Activity

Aims: Raw tropical legumes have abundant amounts of tannins and saponins which are usually eliminated with high temperature once they are cooked. These biomolecules may represent new alternatives, to allopathic medicine, in order to prevent the accumulation of free radicals affecting the cells, or to prevent thrombosis in the blood stream respectively. Therefore the aim of this study was to evaluate the antioxidant and antithrombotic activity attributed to tannins and saponins in whole seeds flour (WSF) and fractions resulting in three types of components: endosperm (flour without hulls ‐Fw/oH-), protein concentrate (PC) and hulls, of two types of tropical legumes Vigna unguiculata (Cowpea) and Mucuna pruriens (Velvet bean). Analysis of nutritional value and also tannins and saponins content was carried out. Finally, antioxidant and antithrombotic activity was also estimated.