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Naoyuki Yamamoto - One of the best experts on this subject based on the ideXlab platform.

  • release of short and proline rich antihypertensive peptides from Casein hydrolysate with an aspergillus oryzae protease
    Journal of Dairy Science, 2004
    Co-Authors: S Mizuno, S Nishimura, K Matsuura, T Gotou, Naoyuki Yamamoto
    Abstract:

    Abstract Angiotensin-I converting enzyme inhibitory activities were measured after hydrolysis of Casein by 9 different commercially available proteolytic enzymes. Among these enzymes, a protease isolated from Aspergillus oryzae showed the highest angiotensin-I converting enzyme inhibitory activity per peptide. The A. oryzae peptide also showed the highest antihypertensive effect in spontaneously hypertensive rats when the systolic blood pressure was measured 5h after oral administration of 32 mg/kg of various enzymatic Hydrolysates. Significant antihypertensive effects were observed with dosages of 9.6, 32, and 96mg of the A. oryzae peptide/kg of body weight (BW), and the effects were dependent on these peptide dosages. Analysis of peptide length showed the A. oryzae hydrolysate was the shortest of all tested Casein Hydrolysates; the peptide mixture had an average value of 1.4 amino acids (AA) in the sequence. To further characterize the A. oryzae hydrolysate, we analyzed the AA sequence of the whole peptide mixture. Various AA were detected at the first AA position, however, an increased number of Pro residues were observed at the second and third position of the A. oryzae hydrolysate. No strong signals were detected after the fourth AA position of the A. oryzae hydrolysate. These results suggest that the Casein hydrolysate of A. oryzae , which expressed potent antihypertensive effects in spontaneously hypertensive rats, mainly contain short peptides of X-Pro and X-Pro-Pro sequences.

  • antihypertensive effect of the peptides derived from Casein by an extracellular proteinase from lactobacillus helveticus cp790
    Journal of Dairy Science, 1994
    Co-Authors: Naoyuki Yamamoto, Atsuko Akino, Toshiaki Takano
    Abstract:

    Abstract Peptides derived from α s1 - and β -Caseins by the Lactobacillus helveticus CP790 proteinase were investigated for their inhibitory activities against angiotensin I-converting enzyme. The antihypertensive effect of Casein Hydrolysates in strain SHR spontaneously hypertensive rats was also investigated. Both α s1 and β -Casein Hydrolysates inhibited this enzyme. Some of these peptides showed enzyme inhibitory activity, and one of them from β -Casein inhibited the enzyme greatly; the concentration of an angiotensin I-converting enzyme inhibitor needed to inhibit 50% of the enzyme activity was 4 μM. The hydrolysate of Casein demonstrated antihypertensive activity in spontaneously hypertensive rats at an orally administered dosage of 15 mg/kg of body weight. Milk fermented with L. helveticus CP790, containing about .3% peptides, also showed antihypertensive activity in SHR rats with 5 ml/kg of body weight (15mg of peptide/kg); however, the milk fermented with L. helveticus CP791, a variant defective for proteinase activity, did not show this activity. Results suggested that the peptides liberated from Casein by the proteinase in the culture medium showed antihypertensive effect in SHR rats.

  • antihypertensive effect of the peptides derived from Casein by an extracellular proteinase from lactobacillus helveticus cp790
    Journal of Dairy Science, 1994
    Co-Authors: Naoyuki Yamamoto, Atsuko Akino, Toshiaki Takano
    Abstract:

    Peptides derived from alpha s1- and beta-Caseins by the Lactobacillus helveticus CP790 proteinase were investigated for their inhibitory activities against angiotensin I-converting enzyme. The antihypertensive effect of Casein Hydrolysates in strain SHR spontaneously hypertensive rats was also investigated. Both alpha s1- and beta-Casein Hydrolysates inhibited this enzyme. Some of these peptides showed enzyme inhibitory activity, and one of them from beta-Casein inhibited the enzyme greatly; the concentration of an angiotensin I-converting enzyme inhibitor needed to inhibit 50% of the enzyme activity was 4 microM. The hydrolysate of Casein demonstrated antihypertensive activity in spontaneously hypertensive rats at an orally administered dosage of 15 mg/kg of body weight. MILK fermented with L. helveticus CP790, containing about .3% peptides, also showed antihypertensive activity in SHR rats with 5 ml/kg of body weight (15 mg of peptide/kg); however, the milk fermented with L. helveticus CP791, a variant defective for proteinase activity, did not show this activity. Results suggested that the peptides liberated from Casein by the proteinase in the culture medium showed antihypertensive effect in SHR rats.

Toshiaki Takano - One of the best experts on this subject based on the ideXlab platform.

  • antihypertensive effect of the peptides derived from Casein by an extracellular proteinase from lactobacillus helveticus cp790
    Journal of Dairy Science, 1994
    Co-Authors: Naoyuki Yamamoto, Atsuko Akino, Toshiaki Takano
    Abstract:

    Abstract Peptides derived from α s1 - and β -Caseins by the Lactobacillus helveticus CP790 proteinase were investigated for their inhibitory activities against angiotensin I-converting enzyme. The antihypertensive effect of Casein Hydrolysates in strain SHR spontaneously hypertensive rats was also investigated. Both α s1 and β -Casein Hydrolysates inhibited this enzyme. Some of these peptides showed enzyme inhibitory activity, and one of them from β -Casein inhibited the enzyme greatly; the concentration of an angiotensin I-converting enzyme inhibitor needed to inhibit 50% of the enzyme activity was 4 μM. The hydrolysate of Casein demonstrated antihypertensive activity in spontaneously hypertensive rats at an orally administered dosage of 15 mg/kg of body weight. Milk fermented with L. helveticus CP790, containing about .3% peptides, also showed antihypertensive activity in SHR rats with 5 ml/kg of body weight (15mg of peptide/kg); however, the milk fermented with L. helveticus CP791, a variant defective for proteinase activity, did not show this activity. Results suggested that the peptides liberated from Casein by the proteinase in the culture medium showed antihypertensive effect in SHR rats.

  • antihypertensive effect of the peptides derived from Casein by an extracellular proteinase from lactobacillus helveticus cp790
    Journal of Dairy Science, 1994
    Co-Authors: Naoyuki Yamamoto, Atsuko Akino, Toshiaki Takano
    Abstract:

    Peptides derived from alpha s1- and beta-Caseins by the Lactobacillus helveticus CP790 proteinase were investigated for their inhibitory activities against angiotensin I-converting enzyme. The antihypertensive effect of Casein Hydrolysates in strain SHR spontaneously hypertensive rats was also investigated. Both alpha s1- and beta-Casein Hydrolysates inhibited this enzyme. Some of these peptides showed enzyme inhibitory activity, and one of them from beta-Casein inhibited the enzyme greatly; the concentration of an angiotensin I-converting enzyme inhibitor needed to inhibit 50% of the enzyme activity was 4 microM. The hydrolysate of Casein demonstrated antihypertensive activity in spontaneously hypertensive rats at an orally administered dosage of 15 mg/kg of body weight. MILK fermented with L. helveticus CP790, containing about .3% peptides, also showed antihypertensive activity in SHR rats with 5 ml/kg of body weight (15 mg of peptide/kg); however, the milk fermented with L. helveticus CP791, a variant defective for proteinase activity, did not show this activity. Results suggested that the peptides liberated from Casein by the proteinase in the culture medium showed antihypertensive effect in SHR rats.

Elvira Maria Hebert - One of the best experts on this subject based on the ideXlab platform.

  • β Casein hydrolysate generated by the cell envelope associated proteinase of lactobacillus delbrueckii ssp lactis crl 581 protects against trinitrobenzene sulfonic acid induced colitis in mice
    Journal of Dairy Science, 2012
    Co-Authors: M Espeche B Turbay, A De Moreno De Leblanc, Gabriela Perdigon, Savoy G De Giori, Elvira Maria Hebert
    Abstract:

    Lactobacillus delbrueckii ssp. lactis CRL 581, a thermophilic lactic acid bacterium used as a starter culture for the manufacture of several fermented dairy products, possesses an efficient proteolytic system that is able to release a series of potentially bioactive peptides (i.e., antihypertensive and phosphopeptides) from α- and β-Caseins. Considering the potential beneficial health effects of the peptides released by L. delbrueckii ssp. lactis CRL 581 from milk proteins, the aim of this work was to analyze the anti-mutagenic and anti-inflammatory properties of the Casein Hydrolysates generated by the cell envelope-associated proteinase of this bacterium. The ability of α- and β-Casein Hydrolysates to suppress the mutagenesis of a direct-acting mutagen 4-nitroquinoline-N-oxide on Salmonella typhimurium TA 98 and TA 100 increased concomitantly with the time of Casein hydrolysis. The anti-inflammatory effect of the β-Casein hydrolysate was evaluated using a trinitrobenzene sulfonic acid (TNBS)-induced Crohn's disease murine model. The hydrolysate was administered to mice 10 d before the intrarectal inoculation of TNBS. The mice that received β-Casein hydrolysate previously to TNBS showed decreased mortality rates, faster recovery of initial body weight loss, less microbial translocation to the liver, decreased β-glucuronidase and myeloperoxidase activities in the gut, and decreased colonic macroscopic and microscopic damage compared with the animals that did not receive this hydrolysate. In addition, β-Casein hydrolysate exerted a beneficial effect on acute intestinal inflammation by increased interleukin 10 and decreased IFN-γ production in the gut. Our findings are consistent with the health-promoting attributes of the milk products fermented by L. delbrueckii ssp. lactis CRL 581 and open up new opportunities for developing novel functional foods.

  • characterization of the pattern of αs1 and β Casein breakdown and release of a bioactive peptide by a cell envelope proteinase from lactobacillus delbrueckii subsp lactis crl 581
    Applied and Environmental Microbiology, 2008
    Co-Authors: Elvira Maria Hebert, Gianfranco Mamone, Gianluca Picariello, Raul R Raya, Graciela Savoy, Pasquale Ferranti, Francesco Addeo
    Abstract:

    The cell envelope-associated proteinases (CEPs) of the lactobacilli have key roles in bacterial nutrition and contribute to the development of the organoleptic properties of fermented milk products as well, as they can release bioactive health-beneficial peptides from milk proteins. The influence of the peptide supply, carbohydrate source, and osmolites on the CEP activity of the cheese starter Lactobacillus delbrueckii subsp. lactis CRL 581 was investigated. The CEP activity levels were controlled by the peptide content of the growth medium. The maximum activity was observed in a basal minimal defined medium, whereas in the presence of Casitone, Casamino Acids, or yeast extract, the synthesis of CEP was inhibited 99-, 70-, and 68-fold, respectively. The addition of specific di- or tripeptides containing branched-chain amino acids, such as leucylleucine, prolylleucine, leucylglycylglycine, or leucylproline, to the growth medium negatively affected CEP activity, whereas dipeptides without branched-chain amino acids had no effect on the enzyme9s production. The carbon source and osmolites did not affect CEP activity. The CEP of L. delbrueckii subsp. lactis CRL 581 exhibited a mixed-type CEPI/III variant Caseinolytic specificity. Mass-spectrometric screening of the main peptide peaks isolated by reverse-phase high-pressure liquid chromatography allowed the identification of 33 and 32 peptides in the αs1- and β-Casein Hydrolysates, respectively. By characterizing the peptide sequence in these Hydrolysates, a pattern of αs1- and β-Casein breakdown was defined and is reported herein, this being the first report for a CEP of L. delbrueckii subsp. lactis. In this pattern, a series of potentially bioactive peptides (antihypertensive and phosphopeptides) which are encrypted within the precursor protein could be visualized.

Shangwu Chen - One of the best experts on this subject based on the ideXlab platform.

  • isolation and identification of dipeptidyl peptidase iv inhibitory peptides from trypsin chymotrypsin treated goat milk Casein Hydrolysates by 2d tlc and lc ms ms
    Journal of Agricultural and Food Chemistry, 2015
    Co-Authors: Ying Zhang, Ran Chen, Shangwu Chen
    Abstract:

    New dipeptidyl peptidase IV (DPP-IV)-inhibitory peptides from trypsin/chymotrypsin-treated goat milk Casein Hydrolysates were isolated and identified by two-dimensional silica thin-layer chromatography (2D-TLC) combined to nano LC-MS/MS. 2D-TLC with chloroform/methanol/25% ammonia (2:2:1) and n-butanol/acetic acid/water (4:1:1) as the first- and second-dimension eluents, respectively, in analytical and semipreparative scales, was set up and verified by reversed-phase high-performance liquid chromatography (RP-HPLC) to be feasible and efficient to separate the Hydrolysates. Five new DPP-IV-inhibitory peptides, four relatively large oligopeptides (MHQPPQPL, SPTVMFPPQSVL, VMFPPQSVL, and INNQFLPYPY), and AWPQYL were identified, and INNQFLPYPY showed a notable IC50 value of 40.08 μM as an uncompetitive inhibitor. Interactive effects on DPP-IV inhibition were also observed among separated fractions and pure synthetic peptide mixtures with concentration-dependent activity. The study gives new insights into goat Casein Hydrolysates with identified DPP-IV-inhibitory peptides efficiently isolated by 2D-TLC, which provides a simple and cost-efficient separation process and is compatible with liquid chromatography-tandem mass spectrometry (LC-MS/MS) identification.

  • Isolation and Identification of Dipeptidyl Peptidase IV-Inhibitory Peptides from Trypsin/Chymotrypsin-Treated Goat Milk Casein Hydrolysates by 2D-TLC and LC–MS/MS
    2015
    Co-Authors: Ying Zhang, Ran Chen, Shangwu Chen
    Abstract:

    New dipeptidyl peptidase IV (DPP-IV)-inhibitory peptides from trypsin/chymotrypsin-treated goat milk Casein Hydrolysates were isolated and identified by two-dimensional silica thin-layer chromatography (2D-TLC) combined to nano LC–MS/MS. 2D-TLC with chloroform/methanol/25% ammonia (2:2:1) and n-butanol/acetic acid/water (4:1:1) as the first- and second-dimension eluents, respectively, in analytical and semipreparative scales, was set up and verified by reversed-phase high-performance liquid chromatography (RP–HPLC) to be feasible and efficient to separate the Hydrolysates. Five new DPP-IV-inhibitory peptides, four relatively large oligopeptides (MHQPPQPL, SPTVMFPPQSVL, VMFPPQSVL, and INNQFLPYPY), and AWPQYL were identified, and INNQFLPYPY showed a notable IC50 value of 40.08 μM as an uncompetitive inhibitor. Interactive effects on DPP-IV inhibition were also observed among separated fractions and pure synthetic peptide mixtures with concentration-dependent activity. The study gives new insights into goat Casein Hydrolysates with identified DPP-IV-inhibitory peptides efficiently isolated by 2D-TLC, which provides a simple and cost-efficient separation process and is compatible with liquid chromatography–tandem mass spectrometry (LC–MS/MS) identification

Xinhuai Zhao - One of the best experts on this subject based on the ideXlab platform.

  • coupled neutrase catalyzed plastein reaction mediated the ace inhibitory activity in vitro of Casein Hydrolysates prepared by alcalase
    International Journal of Food Properties, 2013
    Co-Authors: Xu Wei, Xinhuai Zhao
    Abstract:

    Casein Hydrolysates with a degree of hydrolysis of 13.5% were prepared by hydrolyzing Casein with an alkaline protease Alcalase, and showed ACE-inhibition in vitro with an IC50 value of 45.2 μg/mL. The Hydrolysates were modified by plastein reaction catalyzed by a neutral protease Neutrase to reveal the impact of the coupled Neutrase-catalyzed plastein reaction on the ACE-inhibition of the Casein Hydrolysates. The effects of addition level of Neutrase, substrate concentration, reaction temperature, and time on the plastein reaction of the Casein Hydrolysates were studied with the varying amount of free amino groups of the modified Hydrolysates as index. The results illustrated that the amount of free amino groups of the modified Hydrolysates increased in all occasions, and the addition level of Neutrase, substrate concentration, and reaction time had a clear impact on the plastein reaction. Six modified Hydrolysates were prepared at a substrate concentration of 40% (by weight), Neutrase addition level of ...

  • angiotensin i converting enzyme inhibition and enzymatic resistance in vitro of Casein hydrolysate treated by plastein reaction and fractionated with ethanol water or methanol water
    International Dairy Journal, 2012
    Co-Authors: Hui Sun, Xinhuai Zhao
    Abstract:

    Abstract A Casein hydrolysate was modified by the plastein reaction, fractionated with ethanol/water or methanol/water solvents and further hydrolyzed by four proteases to show the potential impact of these treatments on Angiotensin I converting enzyme (ACE) inhibition in vitro. The treated hydrolysate exhibited a higher ACE-inhibitory activity than did the original hydrolysate: the IC50 value decreased from 52.6 μg mL−1 (original) to 14.9 μg mL−1 (treated). Fractionation of the treated hydrolysate with the lowest polarity solvent led to soluble fractions with a higher activity and precipitate fractions with a lower activity. Hydrolysis of the treated or the fractionated hydrolysate by one of four selected proteases for 10 or 30 min reduced the activity; papain, pepsin or trypsin (but not alcalase) digests had residual activities of about 32–50% at 25 μg mL−1, higher than the original hydrolysate (27.8%). It was concluded that the plastein reaction, but not solvent fractionation, produced Casein Hydrolysates with protease resistance.

  • preparation of alcalase catalyzed Casein plasteins in the presence of proline addition and the ace inhibitory activity of the plasteins in vitro
    European Food Research and Technology, 2010
    Co-Authors: Xinhuai Zhao
    Abstract:

    Casein Hydrolysates were prepared by hydrolysis of Casein with alkaline protease Alcalase for 6 h and showed the highest ACE-inhibitory activity in vitro with an IC50 value of 47.1 μg mL−1. Casein Hydrolysates prepared were subjected to Alcalase-catalyzed plastein reaction in the presence or absence of proline addition to prepare Casein plasteins. Some optimal reaction conditions of plastein reaction in the presence of proline addition were studied using response surface methodology with the decrease in free amino groups in the Casein plasteins as response. When the concentration of Casein Hydrolysates was fixed at 35% (w w−1) and reaction time at 6 h, the optimal conditions were reaction temperature 48 °C, addition level of proline 0.54 mol/mol free amino groups of Casein Hydrolysates and addition level of Alcalase 9.5 kU g−1 proteins. With these conditions, the maximal decrease in free amino groups in Casein plasteins was 195.7 μmol g−1 proteins. The ACE-inhibitory activities of twelve Casein plasteins in vitro, prepared in the presence or absence of proline addition with different reaction extents, were evaluated and compared. The results showed that the ACE-inhibitory activity of the Casein plasteins prepared in the presence of proline addition changed irregularly, different to that of the Casein plasteins prepared in the absence of proline addition, and might relate to the different linking of proline to the peptides in Casein Hydrolysates during plastein reaction. When the Casein plasteins prepared in the presence of proline addition had a decrease in free amino groups 195.7 μmol g−1 proteins, the IC50 value of the Casein plasteins was lowered to 0.2 μg mL−1.

  • an approach to improve ace inhibitory activity of Casein Hydrolysates with plastein reaction catalyzed by alcalase
    European Food Research and Technology, 2009
    Co-Authors: Xinhuai Zhao
    Abstract:

    The preparation method of Casein Hydrolysates with high ACE-inhibitory activity was studied by Alcalase-catalyzed hydrolysis coupled with plastein reaction. Casein Hydrolysates with an IC50 value of about 47 μg mL−1 were first prepared by hydrolysis of Casein with Alcalase and then modified with plastein reaction catalyzed by the same enzyme. The impacts of four reaction conditions on plastein reaction of Casein Hydrolysates were studied, and then optimal conditions were determined using response surface methodology with the decrease of free amino groups in the reaction mixture as response. When the concentration of Casein Hydrolysates was fixed at 35% by weight, the maximum decrease of free amino groups in the reaction mixture of 181.8 μmol g−1 proteins was obtained. The optimum conditions for the above decrease were found to be an E/S ratio of 7.7 kU g−1 proteins, reaction temperature of 42.7 °C and reaction time of 6 h. Analysis results showed that ACE-inhibitory activity of Casein Hydrolysates prepared could be improved significantly by plastein reaction. When Casein Hydrolysates were modified by plastein reaction, with a decrease of free amino groups in the mixture of about 154.7 μmol g−1 proteins and 181.8 μmol g−1 proteins, their IC50 values could be decreased to 0.6 and 0.5 μg mL−1.