Bioactivity of Peptides Released During Lactic Fermentation of Amaranth Proteins with Potential Cardiovascular Protective Effect: An In Vitro Study.

Fermentation has shown to be an effective technique in bioactive peptides release. That is why in this study antihypertensive, antithrombotic, and antioxidant activity was evaluated during amaranth proteins fermentation with Lactobacillus casei Shirota and Streptococcus thermophilus 54102 in mono and combined culture. During fermentation an increase of free amine groups was observed, and no statistical differences among monocultures were shown, getting higher concentration in combined culture. This was related to antihypertensive and antioxidant activities, where the highest values were also found in the combined process (45% of angiotensin-converting enzyme inhibition, and 168 µmol Trolox equivalents per liter [TE/L] for 2,2-diphenyl-1-picrylhydrazyl, 268 µmol TE/L for 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid, and 381 µmol Fe2E/L for ferric reducing ability of plasma). On the contrary, antithrombotic activity was not related to free amine groups during fermentation, having the highest bioactivity in different moments in each experiment. L. casei Shirota and S. thermophilus 54102 are strains that are able to release bioactive peptides from amaranth protein, although amaranth is not a common matrix for the development of lactic acid bacteria. In addition, in this study it was observed for the first time that lactic acid strains are able to release bioactive peptides from amaranth protein. In addition, this methodology could be part for the development of fermented beverages, different from fermented milk, to diversify matrix to obtain a novel functional food.

[The antihypertensive effect of fermented milks]. / El efecto antihipertensivo de las leches fermentadas.

There is a great variety of fermented milks containing lactic acid bacteria that present health-promoting properties. Milk proteins are hydrolyzed by the proteolytic system of these microorganisms producing peptides which may also perform other functions in vivo. These peptides are encrypted within the primary structure of proteins and can be released through food processing, either by milk fermentation or enzymatic hydrolysis during gastrointestinal transit. They perform different activities, since they act in the cardiovascular, digestive, endocrine, immune and nervous systems. Bioactive peptides that have an antihypertensive, antithrombotic, antioxidant and hypocholesterolemic effect on the cardiovascular system can reduce the risk factors for chronic disease manifestation and help improve human health. Most studied bioactive peptides are those which exert an antihypertensive effect by inhibiting the angiotensin-converting enzyme (ACE). Recently, the study of these peptides has focused on the implementation of tests to prove that they have an effect on health. This paper focuses on the production of ACEinhibitory antihypertensive peptides from fermented milks, its history, production and in vivo tests on rats and humans, on which its hypotensive effect has been shown.

El efecto antihipertensivo de las leches fermentadas / The antihypertensive effect of fermented milks

Existe una gran variedad de leches fermentadas con bacterias lácticas, con propiedades que promueven la salud. Recientemente se ha comunicado que las proteínas de los alimentos pueden, además, ejercer otras funciones in vivo, por medio de sus péptidos con actividad biológica. Estos péptidos se encuentran encriptados dentro de la estructura primaria de las proteínas y pueden ser liberados por fermentación de la leche, hidrólisis enzimática, o bien durante el tránsito gastrointestinal. Las funciones que presentan son diversas, ya que pueden actuar en diferentes sistemas del cuerpo humano: el cardiovascular, el digestivo, el endocrino, el inmune y el nervioso. Los péptidos bioactivos que presentan un efecto en el sistema cardiovascular (antihipertensivo, antitrombótico, antioxidante o hipocolesterolémico) pueden reducir los factores de riesgo para la manifestación de enfermedades crónicas y ayudar a mejorar la salud humana. Los péptidos bioactivos más estudiados son aquellos que ejercen un efecto antihipertensivo a través de la inhibición de la enzima convertidora de angiotensina (ACE). Este documento se enfoca en la producción de péptidos antihipertensivos inhibidores de la ACE en leches fermentadas, en su historia, y en las pruebas in vivo realizadas en ratas y en humanos, donde se ha demostrado su efecto hipotensor.

There is a great variety of fermented milks containing lactic acid bacteria that present health-promoting properties. Milk proteins are hydrolyzed by the proteolytic system of these microorganisms producing peptides which may also perform other functions in vivo. These peptides are encrypted within the primary structure of proteins and can be released through food processing, either by milk fermentation or enzymatic hydrolysis during gastrointestinal transit. They perform different activities, since they act in the cardiovascular, digestive, endocrine, immune and nervous systems. Bioactive peptides that have an antihypertensive, antithrombotic, antioxidant and hypocholesterolemic effect on the cardiovascular system can reduce the risk factors for chronic disease manifestation and help improve human health. Most studied bioactive peptides are those which exert an antihypertensive effect by inhibiting the angiotensin-converting enzyme (ACE). Recently, the study of these peptides has focused on the implementation of tests to prove that they have an effect on health. This paper focuses on the production of ACEinhibitory antihypertensive peptides from fermented milks, its history, production and in vivo tests on rats and humans, on which its hypotensive effect has been shown.