In vitro gastrointestinal digestion of purified bovine kappa-casein variants A, B, and E: Effects on antioxidant and angiotensin 1-converting enzyme inhibitory capacity

Petrat-Melin, Bjørn; Kristiansen, Gitte; Le, Thao T.; Poulsen, Nina Aagaard; Larsen, Lotte Bach; Young, Jette F.

doi:10.1016/j.idairyj.2016.02.036

Cited by 16 publications

(7 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The protein contents of the κ-CN isolates were high, and ≥90% wt/wt for all variants, as assessed by protein assay and weighing of the desalted, freeze-dried isolates. As mentioned, the κ-CN was purified under reducing conditions during the ion exchange, as earlier employed, and then considered to reform into the oligomer forms after desalting and concomitant removal of the reducing agent (Groves et al, 1998;Farrell et al, 2003;Petrat-Melin et al, 2016). This was confirmed by our SDS-PAGE analyses.…”

Section: Discussionsupporting

confidence: 69%

“…The obtained precipitates were washed twice with Milli-Q water (Sheng et al, 2021) and then dissolved into 50 mL of Milli-Q water with pH adjusted to 7.0 to 7.5 with 5 M NaOH, followed by dialysis against buffer A [20 mM bis-tris propane, 3.3 M urea, 1 mM 1,4-dithioerythritol (DTE), pH 7.0 by HCl] until the dissolved CN preparations had same conductivities as buffer A. The DTE was included in buffer A to allow for monomer formation of κ-CN during purification (Petrat-Melin et al, 2016), as this was considered to be simpler than isolating the κ-CN in various multimer forms. The purification principle aiming for all κ-CN isoforms was based on fast protein liquid chromatography using ÄKTA fast protein liquid chromatography preparative ion exchange chromatography equipped with UNICORN operating system (GE Healthcare/ Cytiva) basically as described earlier (Petrat-Melin et al, 2016) with the following modifications.…”

Section: Purification Of κ-Cn Variants From Homozygous Milkmentioning

confidence: 99%

“…The DTE was included in buffer A to allow for monomer formation of κ-CN during purification (Petrat-Melin et al, 2016), as this was considered to be simpler than isolating the κ-CN in various multimer forms. The purification principle aiming for all κ-CN isoforms was based on fast protein liquid chromatography using ÄKTA fast protein liquid chromatography preparative ion exchange chromatography equipped with UNICORN operating system (GE Healthcare/ Cytiva) basically as described earlier (Petrat-Melin et al, 2016) with the following modifications. The fast protein liquid chromatograph was equipped with an XK 26/40 column manually packed with Q Sepharose Fast Flow anion exchange resin (Cytiva) with a column volume of 150 mL.…”

Section: Purification Of κ-Cn Variants From Homozygous Milkmentioning

confidence: 99%

“…The κ-CN solution of each genetic variant was prepared by dissolution of purified, freeze-dried κ-CN material into Milli-Q water (Millipore) at 10 mg/mL. The protein concentrations were further measured by bicinchoninic acid assay (Thermo Scientific) as previously described (Petrat-Melin et al, 2016), revealing protein concentrations in purified materials of approximately 80%.…”

Section: Desialylation Of Purified κ-Cn Variants a B And Ementioning

confidence: 99%

See 3 more Smart Citations

Effects of genetic variants and sialylation on in vitro digestibility of purified κ-casein

Sheng

Nielsen

Glantz

et al. 2022

Journal of Dairy Science

Self Cite

View full text Add to dashboard Cite

Milk with different κ-casein (CN) phenotypes has previously been found to influence its gastric digestion rate. Therefore, the aim of the present study is to disentangle contributions of genetic variation and its related sialylation on the in vitro digestion process of κ-CN. Accordingly, κ-CN was purified from milk representing homozygous cows with κ-CN phenotypes AA, BB, or EE and used as substrate molecules in model studies using the INFOGEST 2.0 in vitro static digestion model. Furthermore, the effect of removal of the terminal sialic acids present on the O-linked oligosaccharides of the purified κ-CN A, B, and E protein variants were studied by desialylation enzymatic assays. The κ-CN proteins were purified by reducing anion exchange chromatography with purities of variants A, B, and E of 93.0, 97.1, and 90.0%, respectively. Protein degradations of native and desialylated κ-CN isolates in gastric and intestinal phases were investigated by sodium dodecylsulphate-PAGE, degree of hydrolysis (DH), and liquid chromatography electrospray ionization mass spectrometry. It was shown that after purification, the κ-CN molecules reassembled into multimer states, which then constituted the basis for the digestion studies. As assessed by DH, purified variants A and E were found to exhibit faster in vitro digestion rates in both gastric and intestinal phases compared with variant B. Desialylation increased both gastric and intestinal digestion rates for all variants, as measured by DH. In the gastric phase, desialylation promoted digestion of variant B at a rate comparable with native variants A and E, whereas in the intestinal phase, desialylation of variant B promoted better digestion than native A or E. Taken together, the results confirm that low glycosylation degree of purified κ-CN promotes faster in vitro digestion rates, and that desialylation of the O-linked oligosaccharides further promotes digestion. This finding could be applied to produce dairy products with enhanced digestibility.

show abstract

Section: Discussionsupporting

confidence: 69%

Section: Purification Of κ-Cn Variants From Homozygous Milkmentioning

confidence: 99%

Section: Purification Of κ-Cn Variants From Homozygous Milkmentioning

confidence: 99%

Section: Desialylation Of Purified κ-Cn Variants a B And Ementioning

confidence: 99%

See 2 more Smart Citations

Effects of genetic variants and sialylation on in vitro digestibility of purified κ-casein

Sheng

Nielsen

Glantz

et al. 2022

Journal of Dairy Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…Likewise, the bovine casein hydrolysate from C. scolymus extract showed antioxidant activity against ABTS •+ (1.09 µmol Trolox•mg −1 peptide). This value was higher than that exhibited by a κ-casein hydrolysate from gastrointestinal digestion in vitro (0.53 µmol•mg −1 ) [36].…”

Section: Discussioncontrasting

confidence: 54%

Characterization of Proteolytic Activity of Artichoke (Cynara scolymus L.) Flower Extracts on Bovine Casein to Obtain Bioactive Peptides

Bueno-Gavilá

Abellán

Bermejo

et al. 2020

Animals

View full text Add to dashboard Cite

The aim of this work is to establish the most suitable proteolysis conditions to obtain bovine casein hydrolysates containing peptides with antioxidant and antihypertensive capacity. To this end, the proteolytic activity of Cynara scolymus L. flower extracts was characterized on whole bovine casein, evaluating the effect of several factors (pH, temperature, substrate concentration, enzyme concentration, and hydrolysis time). The optimal conditions to carry out the hydrolysis with the C. scolymus L. extract were as follows: pH 6.2, 50 °C, and 0.023 mg·mL−1 of extract-protein concentration. A Michaelis constant (Km) value of 5.66 mg·mL−1 and a maximum rate of reaction (Vmax) of 8.47 mUAbs∙min−1 were observed. The optimal hydrolysis time was 17 h. The casein hydrolysates obtained with these conditions contained peptides with antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity: 30.89%; Trolox equivalent antioxidant capacity (TEAC) against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free radical (ABTS●+): 4.43 mM Trolox equivalent·mg−1 peptide) and antihypertensive activity, showing 55.05% angiotensin-converting enzyme-I inhibition in vitro.

show abstract

Digestibility of Quinoa (Chenopodium quinoa Willd.) Protein Concentrate and Its Potential to Inhibit Lipid Peroxidation in the Zebrafish Larvae Model

Vilcacundo

Barrio

Carpio

et al. 2017

Plant Foods Hum Nutr

View full text Add to dashboard Cite

Quinoa protein concentrate (QPC) was extracted and digested under in vitro gastrointestinal conditions. The protein content of QPC was in the range between 52.40 and 65.01% depending on the assay used. Quinoa proteins were almost completely hydrolyzed by pepsin at pH of 1.2, 2.0, and 3.2. At high pH, only partial hydrolysis was observed. During the duodenal phase, no intact proteins were visible, indicating their susceptibility to the in vitro simulated digestive conditions. Zebrafish larvae model was used to evaluate the in vivo ability of gastrointestinal digests to inhibit lipid peroxidation. Gastric digestion at pH 1.2 showed the highest lipid peroxidation inhibition percentage (75.15%). The lipid peroxidation activity increased after the duodenal phase. The digest obtained at the end of the digestive process showed an inhibition percentage of 82.10%, comparable to that showed when using BHT as positive control (87.13%).

show abstract

In vitro gastrointestinal digestion of purified bovine kappa-casein variants A, B, and E: Effects on antioxidant and angiotensin 1-converting enzyme inhibitory capacity

Cited by 16 publications

References 43 publications

Effects of genetic variants and sialylation on in vitro digestibility of purified κ-casein

Effects of genetic variants and sialylation on in vitro digestibility of purified κ-casein

Characterization of Proteolytic Activity of Artichoke (Cynara scolymus L.) Flower Extracts on Bovine Casein to Obtain Bioactive Peptides

Digestibility of Quinoa (Chenopodium quinoa Willd.) Protein Concentrate and Its Potential to Inhibit Lipid Peroxidation in the Zebrafish Larvae Model

Contact Info

Product

Resources

About