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1.
Curr Microbiol ; 79(4): 99, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35150334

RESUMO

Mycotoxins may be present in nuts, coffee, cereals, and grapes, among other products. Increasing concerns about human health and environmental protection have driven the application of biological control techniques that can inhibit fungal contaminants. In this study, the growth inhibition of the ochratoxigenic fungus Aspergillus carbonarius Ac 162 was evaluated using 5 lactic acid bacteria (LAB). The LAB studied were Lactobacillus plantarum MZ801739 (J), Lactobacillus plantarum MZ809351 (31) and Lactobacillus plantarum MZ809350 (34), isolated in the Ivory Coast, and Lactobacillus plantarum MN982928 (3) and Leuconostoc citreum MZ801735 (23), isolated in Mexico. J, 31, 34, 3 and 23 are the internal strain codes from our laboratory. LAB were cultivated in De Man, Rogosa and Sharpe (MRS) broth, and different polyols (glycerol, mannitol, sorbitol, and xylitol) were added to the culture broth to stimulate the production of antifungal compounds. The fungal inhibition studies were performed using the poisoned food technique. The highest inhibition of A. carbonarius growth was obtained by cultivating L. plantarum MZ809351 in the presence of xylitol and glycerol. Under these conditions, 1 L of the L. plantarum MZ809351 cultures were used to identify antifungal compounds. The compounds were concentrated by solid-phase extraction and then characterized by GC-MS. In addition to 9-octadecenoic acid, 3 diketopiperazines or cyclic dipeptides were identified, including cyclo (Leu-Leu), cyclo (Pro-Gly) and cyclo (Val-Phe), which were compounds related to microbial antifungal activities. Xylitol and glycerol induced the production of these antifungal compounds against A. carbonarius Ac 162. On the other hand, adding xylitol and glycerol to the MRS broth reduced the Ochratoxin A (OTA) content to 56.8 and 54.7%, respectively. This study shows the potential for using L. plantarum MZ809351 as a biocontrol agent to prevent the growth of A. carbonarius and reduce the production of OTA in foods.


Assuntos
Lactobacillus plantarum , Micotoxinas , Antifúngicos/farmacologia , Humanos , Polímeros
2.
Nat Prod Res ; 36(13): 3485-3488, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33356582

RESUMO

Amaranth is a protein-rich seed, highly consumed in Mexico and reported as a potential source of bio-peptides with physiological function. Therefore, the objective of this study was to evaluate and identify bioactive peptide sequences from amaranth protein fractions released by pepsin and pancreatin in vitro digestion. Multifunctional bioactivities of peptides were measured through antihypertensive, antithrombotic and antioxidant assays. Peptide sequences were identified by analysis with a Nano-LC-ESI-MS/MS. With these results, it was demonstrated that the in vitro enzymatic digestion mechanism allows the release of multifunctional bioactive peptide fractions from amaranth proteins.


Assuntos
Amaranthus , Digestão , Peptídeos/farmacologia , Proteínas de Plantas , Espectrometria de Massas em Tandem
3.
Appl Biochem Biotechnol ; 193(11): 3553-3569, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34312785

RESUMO

The effects of water activity (aw), pH, and temperature on transglycosylation activity of α-L-fucosidase from Thermotoga maritima in the synthesis of fucosylated oligosaccharides were evaluated using different water-organic cosolvent reaction systems. The optimum conditions of transglycosylation reaction were the pH range between 7 and 10 and temperature 90-95 °C. The addition of organic cosolvent decreased α-L-fucosidase transglycosylation activity in the following order: acetone > dimethyl sulfoxide (DMSO) > acetonitrile (0.51 > 0.42 > 0.18 mM/h). However, the presence of DMSO and acetone enhanced enzyme-catalyzed transglycosylation over hydrolysis as demonstrated by the obtained transglycosylation/hydrolysis rate (rT/H) values of 1.21 and 1.43, respectively. The lowest rT/H was calculated for acetonitrile (0.59), though all cosolvents tested improved the transglycosylation rate in comparison to a control assay (0.39). Overall, the study allowed the production of fucosylated oligosaccharides in water-organic cosolvent reaction media using α-L-fucosidase from T. maritima as biocatalyst.


Assuntos
Proteínas de Bactérias/química , Fucose/química , Oligossacarídeos/síntese química , Thermotoga maritima/enzimologia , alfa-L-Fucosidase/química , Solventes/química , Água/química
4.
Extremophiles ; 25(3): 311-317, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33938983

RESUMO

Fucosylated oligosaccharides present in human milk perform various biological functions that benefit infants' health. These compounds can be also obtained by enzymatic synthesis. In this work, the effect of the immobilization of α-L-fucosidase from Thermotoga maritima on the synthesis of fucosylated oligosaccharides was studied, using lactose and 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) as acceptor and donor substrates, respectively, and Eupergit® CM as an immobilization support. The enzyme was immobilized with 90% efficiency at pH 8 and ionic strength of 1.5 M. Immobilization decreased enzyme affinity for the donor substrate as shown by a 1.5-times higher KM value and a 22-times decrease of the kcat/KM ratio in comparison to the unbound enzyme. In contrast, no effect was observed on the synthesis/hydrolysis ratio (rs/rh) when α-L-fucosidase was immobilized. Also, the effect of initial concentration of substrates was studied. An increase of the acceptor concentration improved the yields of fucosylated oligosaccharides regardless enzyme immobilization. The synthesis yields of 38.9 and 40.6% were obtained using Eupergit® CM-bound or unbound enzyme, respectively, and 3.5 mM pNP-Fuc and 146 mM lactose. In conclusion, α-L-fucosidase from Thermotoga maritima was efficiently immobilized on Eupergit® CM support without affecting the synthesis of fucosylated oligosaccharides.


Assuntos
Thermotoga maritima , alfa-L-Fucosidase , Fucose , Oligossacarídeos , Especificidade por Substrato , Thermotoga , Thermotoga maritima/metabolismo , alfa-L-Fucosidase/metabolismo
5.
J Photochem Photobiol B ; 209: 111957, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32682284

RESUMO

Since the high incidence of aflatoxin M1 (AFM1) in milk and dairy products poses a serious risk to human health, this work aimed to investigate the complex formation between bovine α-lactalbumin (α-La) and AFM1 using different spectroscopic methods coupled with molecular docking studies. Fluorescence spectroscopy measurements demonstrated the AFM1 addition considerably reduced the α-La fluorescence intensity through a static quenching mechanism. The results indicated on the endothermic character of the reaction, and the hydrophobic interaction played a major role in the binding between AFM1 and α-La. The binding site stoichiometric value (n = 1.32) and a binding constant of 2.12 × 103 M-1 were calculated according to the Stern-Volmer equation. The thermodynamic parameters ΔH, ΔS and ΔGb were determined at 93.58 kJ mol-1, 0.378 kJ mol-1 K-1 and -19.17 ±â€¯0.96 kJ mol-1, respectively. In addition, far-UV circular dichroism studies revealed alterations in the α-La secondary structures when the α-La-AFM1 complex was formed. An increased content of the α-helix structures (from 35 to 40%) and the ß-sheets (from 16 to 19%) were observed. Furthermore, protein-ligand docking modelling demonstrated AFM1 could bind to the hydrophobic regions of α-La protein. Overall, the gathered results confirmed the α-La-AFM1 complex formation.


Assuntos
Aflatoxina M1/química , Contaminação de Alimentos/análise , Lactalbumina/química , Animais , Sítios de Ligação , Bovinos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Leite/química , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Soroalbumina Bovina/química , Termodinâmica
6.
Rev Argent Microbiol ; 52(4): 305-314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31964562

RESUMO

The health benefits attributed to probiotics generate interest in the search of competent strains adapted to several ecological niches, especially those related to traditional beverages and foods of each country. Pineapple tepache, a traditional Mexican fermented beverage, was used for the isolation of lactic acid bacteria with probiotic potential, one of which withstood the in vitro tests. The isolated strain AB-05, which exhibited the tested probiotic functional properties, was designated as Lactobacillus pentosus ABHEAU-05. The sequence was registered in GenBank under access code MK587617. This study is the first report of a lactic acid bacterium with in vitro digestion resistance isolated from pineapple tepache. The survival of L. pentosus ABHEAU-05 in a symbiotic medium was proven using fermented milk enriched with inulin. The in vitro digestion-resistant probiotic activity of lactobacilli was measured through analysis of pH and proteolysis. Results showed that L. pentosus grew properly in fermented milk; therefore, this microorganism could be used in the manufacture of this kind of products. The concentration of L. pentosus reached up to 8.5logCFU/ml after 40h of fermentation. In addition, the production of peptides and the decrease in pH indicated the vigorous and active metabolic state of the lactic acid bacterium tested. The activity and the concentration of this microorganism were maintained during refrigeration. The results of this research conclude that L. plantarum ABHEAU-05 is an in vitro digestion-resistant microorganism that can be used as a starter culture for the production of functional foods of dairy origin.


Assuntos
Alimentos Fermentados , Lactobacillus pentosus , Probióticos , Bebidas , Digestão , Fermentação , Microbiologia de Alimentos , Ácido Láctico
7.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438557

RESUMO

Amaranthus hypochondriacus spp. is a commonly grown cereal in Latin America, known for its high protein content. The objective of this study was to separate and identify bioactive peptides found in amaranth seeds through enzymatically-assisted hydrolysis using alcalase and flavourzyme. Hydrolysis was carried out for each enzyme separately and compared to two-step continuous process where both enzymes were combined. The biological activity of the resulting three hydrolysates was analyzed, finding, in general, higher bioactive potential of the hydrolysate obtained in a continuous process (combined enzymes). Its fractions were separated by RP-HPLC, and their bioactivity was analyzed. In particular, two fractions showed the highest biological activity as ACE inhibitors with IC50 at 0.158 and 0.134, thrombin inhibitors with IC50 of 167 and 155, and antioxidants in ABTS assay with SC50 at 1.375 and 0.992 mg/L, respectively. Further sequence analysis of the bioactive peptides was carried out using MALDI-TOF, which identified amino acid chains that have not been reported as bioactive so far. Bibliographic survey allowed identification of similarities between peptides reported in amaranth and other proteins. In conclusion, amaranth proteins are a potential source of peptides with multifunctional activity.


Assuntos
Amaranthus/química , Peptídeos/química , Proteínas de Plantas/química , Sementes/química , Endopeptidases/metabolismo , Subtilisinas/metabolismo
8.
Molecules ; 24(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261855

RESUMO

Fucosyl-oligosaccharides are natural prebiotics that promote the growth of probiotics in human gut and stimulate the innate immune system. In this work, the release of α-lfucosidase by Lactobacillus rhamnosus GG, and the use of this enzyme for the synthesis of fucosyl-oligosaccharides were investigated. Since α-lfucosidase is a membrane-bound enzyme, its release from the cells was induced by addition of 4-nitrophenyl-α-l-fucopyranoside (pNP-Fuc). Enzyme activity associated with the cell was recovered at 78% of its total activity. Fucosyl-oligosaccharides where synthesized using α-l-fucosidase extract and pNP-Fuc as donor substrate, and D-lactose or D-lactulose as acceptor substrates, reaching a yield up to 25%. Fucosyllactose was obtained as a reaction product with D-lactose, and its composition was confirmed by mass spectrometry (MALDI-TOF MS). It is possible that the fucosyl-oligosaccharide synthesized in this study has biological functions similar to human milk oligosaccharides.


Assuntos
Lacticaseibacillus rhamnosus/enzimologia , Oligossacarídeos/biossíntese , alfa-L-Fucosidase/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Parede Celular/enzimologia , Cromatografia Líquida de Alta Pressão , Glicosídeos/química , Humanos , Espectrometria de Massas , Oligossacarídeos/química , Prebióticos , Especificidade por Substrato , alfa-L-Fucosidase/metabolismo
9.
J Med Food ; 22(10): 976-981, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31211650

RESUMO

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.


Assuntos
Amaranthus/química , Fermentação , Lactobacillales/metabolismo , Peptídeos/farmacologia , Proteínas de Plantas/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Antioxidantes/farmacologia , Antitrombinas/farmacologia , Ácido Láctico/metabolismo , Lacticaseibacillus casei , Sementes/química , Streptococcus thermophilus
10.
Appl Biochem Biotechnol ; 188(2): 369-380, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30467689

RESUMO

Glycosylhydrolases of various origins were used to produce fucose-containing disaccharides with prebiotic potential using different donor substrates and L-fucose as the acceptor substrate. Eight different disaccharides were synthesized as follows: three ß-D-galactosyl-L-fucosides with glycosidase CloneZyme Gly-001-02 using D-lactose as a donor substrate, two with a structure similar to prebiotics; one ß-D-galactosyl-L-fucose with ß-D-galactosidase from Aspergillus oryzae using D-lactose as a substrate donor; and four α-D-glucosyl-L-fucosides with α-D-glucosidase from Saccharomyces cerevisiae using D-maltose as a donor substrate. All disaccharides were purified and hydrolyzed. In all cases, an L-fucose moiety was present, and it was confirmed for ß-D-galactosyl-L-fucose by mass spectrometry. High concentrations of L-fucose as the acceptor substrate enhanced the synthesis of the oligosaccharides in all cases. The three enzymes were able to synthesize fucose-containing disaccharides when L-fucose was used as the acceptor substrate, and the highest yield was 20% using ß-D-galactosidase from Aspergillus oryzae.


Assuntos
Dissacarídeos/biossíntese , Fucose/metabolismo , Glicosídeo Hidrolases/metabolismo , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Aspergillus oryzae/enzimologia , Biotecnologia , Dissacarídeos/química , Fucose/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/isolamento & purificação , Glicosilação , Lactose/metabolismo , Prebióticos , Saccharomyces cerevisiae/enzimologia , Especificidade por Substrato , alfa-Glucosidases/isolamento & purificação , alfa-Glucosidases/metabolismo , beta-Galactosidase/isolamento & purificação , beta-Galactosidase/metabolismo
11.
Biotechnol Appl Biochem ; 66(2): 172-191, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30508310

RESUMO

Fucosylated oligosaccharides play important physiological roles in humans, including in the immune response, transduction of signals, early embryogenesis and development, growth regulation, apoptosis, pathogen adhesion, and so on. Efforts have been made to synthesize fucosylated oligosaccharides, as it is difficult to purify them from their natural sources, such as human milk, epithelial tissue, blood, and so on. Within the strategies for its in vitro synthesis, it is remarkable the employment of fucosidases, enzymes that normally cleave the fucosyl residue from the non-reducing end of fucosylated compounds, as these enzymes are also capable of synthesizing them by means of a transfucosylation reaction. This review summarizes the progress in the use of fucosidases for the synthesis of compounds that have potential for industrial and commercial applications.


Assuntos
Fucose/química , Oligossacarídeos/síntese química , alfa-L-Fucosidase/química , Oligossacarídeos/química
12.
Extremophiles ; 22(6): 889-894, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30088105

RESUMO

The influence of CaCl2 and NaCl in the hydrolytic activity and the influence of CaCl2 in the synthesis of fucosylated oligosaccharides using α-L-fucosidase from Thermotoga maritima were evaluated. The hydrolytic activity of α-L-fucosidase from Thermotoga maritima displayed a maximum increase of 67% in the presence of 0.8 M NaCl with water activity (aw) of 0.9672 and of 138% in the presence of 1.1 M CaCl2 (aw 0.9581). In addition, the hydrolytic activity was higher when using CaCl2 compared to NaCl at aw of 0.8956, 0.9581 and 0.9672. On the other hand, the effect of CaCl2 in the synthesis of fucosylated oligosaccharides using 4-nitrophenyl-fucose as donor substrate and lactose as acceptor was studied. In these reactions, the presence of 1.1 M CaCl2 favored the rate of transfucosylation, and improved the yield of synthesis duplicating and triplicating it with lactose concentrations of 58 and 146 mM, respectively. CaCl2 did not significatively affect hydrolysis rate in these reactions. The combination of the activating effect of CaCl2, the decrement in aw and lactose concentration had a synergistic effect favoring the synthesis of fucosylated oligosaccharides.


Assuntos
Proteínas de Bactérias/metabolismo , Oligossacarídeos/biossíntese , Thermotoga maritima/enzimologia , alfa-L-Fucosidase/metabolismo , Cálcio/metabolismo , Fucose/análogos & derivados , Sódio/metabolismo
13.
Ultrason Sonochem ; 48: 396-403, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080565

RESUMO

The aim of this research was to determine the physicochemical properties, microbial counts and aflatoxin M1 (AFM1) levels of thermoultrasonicated, pasteurized and untreated milk (control) at days 1, 7 and 14 of storage. Thermoultrasound treatment was performed at a rate of 20 kHz for 10 or 15 min and 95% amplitude on homogenized and non-homogenized milk samples. Results showed that most physicochemical parameters were within the Mexican norms established for milk. Ultrasound treatment for 15 min reduced solids precipitation (p < 0.05) in unhomogenized milk during storage as compared to the pasteurized milk. All samples complied with aerobic mesophilic counts limits set by the Mexican norm except the control and the homogenized milk sample which was thermoultrasonicated for 10 min. Enterobacteriaceae counts of pasteurized and 15 min-thermoultrasound homogenized milks complied with the norm. The lowest levels of AFM1 were found in the 10 min-thermoultrasound unhomogenized milk (0.15 ±â€¯0.05 pg AFM⁠1E/mL) one day after storage. Thermoultrasound did not affect the color of samples but homogenized milk treated for 10 min exhibited less total color difference. A high phenolic content was found in thermoultrasound and pasteurized milks on day 1. Thermoultrasound could be an alternative to milk pasteurization that preserves the physicochemical and microbiological quality of milk while reducing AFM1 levels.


Assuntos
Aflatoxina M1/análise , Enterobacteriaceae/isolamento & purificação , Microbiologia de Alimentos , Armazenamento de Alimentos , Leite/química , Leite/microbiologia , Pasteurização/métodos , Sonicação/métodos , Animais , Antioxidantes/farmacologia , Bovinos , Contagem de Colônia Microbiana , Cor , Sequestradores de Radicais Livres/farmacologia , México , Fenóis/análise
14.
Appl Biochem Biotechnol ; 186(3): 681-691, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29717409

RESUMO

Fucosylated oligosaccharides, such as 2'-fucosyllactose in human milk, have important biological functions such as prebiotics and preventing infection. In this work, the effect of an acceptor substrate (lactose) and the donor substrate 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) on the synthesis of a fucosylated trisaccharide was studied in a transglycosylation reaction using α-L-fucosidase from Thermotoga maritima. Conducting a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), it was demonstrated that synthesized oligosaccharide corresponded to a fucosylated trisaccharide, and high-performance liquid chromatography (HPLC) of the hydrolyzed compound confirmed it was fucosyllactose. As the concentration of the acceptor substrate increased, the concentration and synthesis rate of the fucosylated trisaccharide also increased, and the highest concentration obtained was 0.883 mM (25.2% yield) when using the higher initial lactose concentration (584 mM). Furthermore, the lower donor/acceptor ratio had the highest synthesis, so at the molar ratio of 0.001, a concentration of 0.286 mM was obtained (32.5% yield).


Assuntos
Fucose/biossíntese , Thermotoga maritima/enzimologia , Trissacarídeos/metabolismo , alfa-L-Fucosidase/metabolismo , Cromatografia Líquida de Alta Pressão , Fucose/metabolismo , Glicosilação , Lactose/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato
15.
Rev Argent Microbiol ; 46(1): 58-65, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-24721277

RESUMO

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.


Assuntos
Produtos Fermentados do Leite , Hipertensão/dietoterapia , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Animais , Bifidobacterium/enzimologia , Bovinos , Produtos Fermentados do Leite/enzimologia , Produtos Fermentados do Leite/microbiologia , Humanos , Lactobacillus/enzimologia , Lactococcus/enzimologia , Proteínas do Leite/metabolismo , Peptídeos/farmacocinética , Peptídeos/farmacologia , Ratos , Streptococcus/enzimologia
16.
Rev. argent. microbiol ; 46(1): 58-65, mar. 2014. tab
Artigo em Espanhol | LILACS | ID: lil-708697

RESUMO

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.


Assuntos
Animais , Bovinos , Humanos , Ratos , Produtos Fermentados do Leite , Hipertensão/dietoterapia , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Bifidobacterium/enzimologia , Produtos Fermentados do Leite/enzimologia , Produtos Fermentados do Leite/microbiologia , Lactobacillus/enzimologia , Lactococcus/enzimologia , Proteínas do Leite/metabolismo , Peptídeos/farmacocinética , Peptídeos/farmacologia , Streptococcus/enzimologia
17.
J Sci Food Agric ; 94(11): 2246-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24374769

RESUMO

BACKGROUND: Probiotics and prebiotics are among the most important functional food ingredients worldwide. The proven benefits of such ingredients to human health have encouraged the development of functional foods containing both probiotics and prebiotics. In this work, the production of antimicrobial compounds coupled to the uptake of commercial prebiotics by probiotic bacteria was investigated. RESULTS: The probiotic bacteria studied were able to take up commercial prebiotic carbohydrates to the same or higher extent than that observed for lactose (control carbohydrate). The growth of probiotic bacteria was coupled to the production of antimicrobials such as short-chain fatty acids (SCFA), H2 O2 and bacteriocins. A higher production of antimicrobial compounds was recorded with Oligomate 55® compared with Regulact® and Frutafit® (3-5 and 10-115 times higher SCFA and H2 O2 production, respectively). The probiotic bacteria grown with Oligomate 55® also produced bacteriocins and other non-identified antimicrobial compounds. The antimicrobials produced by the probiotic bacteria inhibited up to 50% the growth of model pathogens such as Escherichia coli, Listeria innocua and Micrococcus luteus compared with control cultures. CONCLUSIONS: The results here obtained are useful for the adequate selection of probiotic/prebiotics pairs and therefore in the development of efficient functional foods.


Assuntos
Anti-Infecciosos/farmacologia , Bacteriocinas/biossíntese , Ácidos Graxos Voláteis/biossíntese , Peróxido de Hidrogênio/metabolismo , Lactobacillus/metabolismo , Prebióticos , Probióticos/metabolismo , Antibiose , Bacteriocinas/farmacologia , Comércio , Carboidratos da Dieta/metabolismo , Escherichia coli/efeitos dos fármacos , Ácidos Graxos Voláteis/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Listeria/efeitos dos fármacos , Micrococcus/efeitos dos fármacos , Simbióticos
18.
Biotechnol Prog ; 29(2): 337-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23341203

RESUMO

The highest enzymatic extraction of covalent linked chlorogenic (36.1%) and caffeic (CA) (33%) acids from coffee pulp (CP) was achieved by solid-state fermentation with a mixture of three enzymatic extracts produced by Aspergillus tamarii, Rhizomucor pusillus, and Trametes sp. Enzyme extracts were produced in a practical inexpensive way. Synergistic effects on the extraction yield were observed when more than one enzyme extract was used. In addition, biotransformation of chlorogenic acid (ChA) by Aspergillus niger C23308 was studied. Equimolar transformation of ChA into CA and quinic acids (QA) was observed during the first 36 h in submerged culture. Subsequently, after 36 h, equimolar transformation of CA into protocatechuic acid was observed; this pathway is being reported for the first time for A. niger. QA was used as a carbon source by A. niger C23308. This study presents the potential of using CP to produce enzymes and compounds such as ChA with biological activities.


Assuntos
Aspergillus/enzimologia , Ácido Clorogênico/metabolismo , Coffea/metabolismo , Proteínas Fúngicas/metabolismo , Microbiologia Industrial/métodos , Rhizomucor/enzimologia , Trametes/enzimologia , Aspergillus/metabolismo , Biotransformação , Ácidos Cafeicos/metabolismo , Ácido Clorogênico/isolamento & purificação , Coffea/química , Fermentação , Proteínas Fúngicas/química , Resíduos Industriais/análise , Rhizomucor/metabolismo , Trametes/metabolismo
19.
Anaerobe ; 17(6): 267-72, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21497665

RESUMO

Coffee contamination by ochratoxigenic fungi affects both coffee quality as well as coffee price with harmful consequences on the economy of the coffee exporting countries for whom which is their main source of income. Fungal strains were isolated from coffee beans and identified as black Aspergilli. Ochratoxigenic moulds like Aspergillus carbonarius were screened and selected for detailed studies. Also lactic acid bacteria (LAB) were isolated from silage coffee pulp and their antifungal activity was tested on dual-culture agar plate. Ten of the isolated LAB demonstrated antifungal effect against A. carbonarius. API 50 CH and APIZYM were used to perform phenotypic identification. 16S rDNA sequencing was made to confirm the results.


Assuntos
Aspergillus/crescimento & desenvolvimento , Coffea/microbiologia , Lactobacillus plantarum/fisiologia , Interações Microbianas , Aspergillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Metabolismo dos Carboidratos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Enzimas/metabolismo , Lactobacillus plantarum/classificação , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , RNA Ribossômico 16S/genética , Sementes/microbiologia , Análise de Sequência de DNA
20.
Bioresour Technol ; 101(12): 4721-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20153180

RESUMO

Ferulic acid biotransformation has a number of interesting industrial uses. Ferulic acid biotransformation by the wild strain Aspergillus niger C28B25 and a diploid strain DAR2, obtained by parasexual recombination, was studied. The wild strain of A.niger C28B25 biotransforms ferulic acid to vanillic acid (VA); while the diploid strain DAR2 preferentially decarboxylates ferulic acid to 4-vinylguaiacol (4VG). The latter was identified by mass spectroscopy, (1)H and (13)C nuclear magnetic resonance spectroscopy, and quantified by HPLC. The diploid strain A.niger DAR2 and the wild strain showed a ferulic acid conversion of 64% and 36%, respectively. Molar yields show that the formation of 4VG was preferred, being as much as 4.4 times higher than the formation of VA in diploid strain cultures. Differential regulation of enzymes involved in the biotransformation of ferulic acid may explain the accumulation of 4VG by diploid DAR2. This strain produced both 4VG and VA.


Assuntos
Aspergillus niger/metabolismo , Ácidos Cumáricos/metabolismo , Guaiacol/análogos & derivados , Biotransformação , Ácidos Cumáricos/química , Guaiacol/química , Guaiacol/metabolismo , Ácido Vanílico/metabolismo
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