432 research outputs found
Recent advances in the production of emulsifying peptides with the aid of proteomics and bioinformatics
Food industry aims to develop novel protein-based emulsifiers from sustainable sources (e.g. plants, seaweed/microalgae, microbial, and insects) to satisfy the clean-label demand by consumers. Enzymatic hydrolysis releases peptides with enhanced surface properties compared with the parent alternative proteins. Traditionally, a trial-and-error top-down approach, which requires extensive costs in screening analyses, has been carried out to produce emulsifying peptides. This review presents the recent advances in a novel and fundamentally orthogonal bottom-up strategy, facilitated by quantitative proteomics and bioinformatic functional prediction, to produce emulsifying peptides by targeted enzymatic hydrolysis based on in silico proteolysis. Moreover, new insights on the relation between interfacial properties of peptides and emulsifying activity, as well as impact on stability of wet and dried emulsions, are discussed.Innovation Fund Denmark (Grant nr: 7045-00021B, PROVIDE project
Antioxidant peptides derived from potato, seaweed, microbial and spinach proteins: Oxidative stability of 5% fish oil-in-water emulsions
This work was part of PROVIDE (Protein valorization through informatics, hydrolysis, and separation) project, which is supported by Innovation Fund Denmark (Grant No.: 7045-00021B) . We acknowledge ISA, Centre for Storage Ring Facilities in Aarhus, Denmark, for granting the beam time (Grant No.: ISA-20-1005) . We thank Lis Berner for her help in the lab with the production and physicochemical characterization of the emulsions. We also acknowledge the companies involved and provided the original samples used as source materials: KMC Kartoffelmelcentralen amba (Brande, Denmark) , AKV Langholt amba (Langholt, Denmark) , CP Kelco (Lille Skensved, Denmark) , Unibio A/S (Odense, Denmark) , and Lihme Protein Solutions (Kgs. Lyngby, Denmark) .In this study, we used a combination of quantitative proteomics and bioinformatic prediction for identifying
novel antioxidant peptides. Thirty-five peptides from potato, seaweed, microbial, and spinach proteins were
investigated. Based on high DPPH radical scavenging activity (IC50 †16 mg/mL), metal chelation activity,
isoelectric point, and high relative abundance in the parent protein sources, 11 peptides were selected. Lipid
oxidation retardation was evaluated in 5% fish oil-in-water emulsions stabilized with Tween 20, where emulsion
physical stability was unaffected by peptide addition. The secondary structure of selected peptides was similar in
the aqueous solution and emulsions, as confirmed by synchrotron radiation circular dichroism spectroscopy. The
emulsions containing the selected peptides had lower levels of hydroperoxides and volatile compounds during
storage compared to the control (without peptide). This study contributes to elucidating the effect of antioxidant
peptides in emulsions and demonstrates the ability of quantitative proteomics and bioinformatics prediction to
identify peptides with strong antioxidant properties.Innovation Fund Denmark 7045-00021BISA, Centre for Storage Ring Facilities in Aarhus, Denmark ISA-20-100
Antioxidant peptides from alternative sources reduce lipid oxidation in 5% fish oil-in-water emulsions (pH 4) and fish oil-enriched mayonnaise
Bioinformatics tools were used to predict radical scavenging and metal chelating activities of peptides derived
from abundant potato, seaweed, microbial, and spinach proteins. The antioxidant activity was evaluated in 5%
oil-in-water emulsions (pH4) and best-performing peptides were tested in mayonnaise and compared with EDTA.
Emulsion physical stability was intact. The peptide DDDNLVLPEVYDQD showed the highest protection against
oxidation in both emulsions by retarding the formation of oxidation products and depletion of tocopherols during
storage, but it was less efficient than EDTA when evaluated in mayonnaise. In low-fat emulsions, formation of
hydroperoxides was reduced 4-folds after 5 days compared to control. The concentration effect of the peptide
was confirmed in mayonnaise at the EDTA equimolar concentration. The second-best performing peptides were
NNKWVPCLEFETEHGFVYREHH in emulsion and AGDWLIGDR in mayonnaise. In general, the peptide efficacy
was higher in low-fat emulsions. Results demonstrated that peptide negative net charge was important for
chelating activity.Innovation Fund Denmark (Grant No.: 7045-00021B)
Physical and oxidative stability of fish oil-in-water emulsions stabilized with emulsifier peptides derived from seaweed, methanotrophic bacteria and potato proteins
This study investigated the emulsifying and antioxidant activity of 10 peptides derived from seaweed, methanotrophic
bacteria, and potatoes, which were identified as emulsifiers using quantitative proteomics and predictive
bioinformatics. The factors (e.g., interfacial properties, secondary structure, net charge) behind the dualfunctionality
of peptides were characterized and related to peptidesâ ability to provide physical and oxidative
stability in 5 % fish oil-in-water emulsions during 10 days of storage. The secondary structure of some of the
peptides changed from highly disordered to more α-helical (GIIPATILEFLEGQLQEVDNNKDAR and GIIPGTILEFLEGQLQK)
or ÎČ-strand (VGFACSGSAQTYLSFEGDNTGRGEEEVAI, ELQVSARVTLEIEL, KVKINETVEIKGKFHV,
RSPQKKESDMMKATKFAVVLMAAGLTVGCA) structures when adsorbed at the oil-water interface in comparisonInnovation Fund Denmark (Grant no.: 7045-00021B
Physical and Oxidative Stability of Emulsions Stabilized with Fractionated Potato Protein Hydrolysates Obtained from Starch Production Side Stream
Supplementary Materials: The following supporting information can be downloaded at:
https://www.mdpi.com/article/10.3390/antiox12081622/s1This work studies the emulsifying and antioxidant properties of potato protein hydrolysates (PPHs) fractions obtained through enzymatic hydrolysis of potato protein using trypsin followed by ultrafiltration. Unfractionated (PPH1) and fractionated (PPH2 as >10 kDa, PPH3 as 10-5 kDa, PPH4 as 5-0.8 kDa, and PPH5 as 10 kDa showed the highest ability to decrease oil-water interfacial tension. All PPH fractions predominantly provided elastic, weak, and easily stretchable interfaces. PPH2 provided a more rigid interfacial layer than the other hydrolysates. Radical scavenging and metal chelating activities of PPHs were also tested and the highest activities were provided by the unfractionated hydrolysate and the fractions with peptides >5 kDa. Furthermore, the ability of PPHs to form physically and oxidatively stable 5% fish oil-in-water emulsions (pH 7) was investigated during 8-day storage at 20 ffi C. Our results generally show that the fractions with peptides >5 kDa provided the highest physicochemical stability, followed by the fraction with peptides between 5 and 0.8 kDa. Lastly, promising sensory results with mostly mild attributes were obtained even at protein concentration levels that are higher than needed to obtain functional properties. The more prominent attributes (e.g., bitterness and astringency) were within an acceptable range for PPH3 and PPH4.Innovation Fund Denmark, 7045-00021B
(PROVIDE Project
The Use of Soy and Egg Phosphatidylcholines Modified with Caffeic Acid Enhances the Oxidative Stability of High-Fat (70%) Fish Oil-in-Water Emulsions
This study investigated the effect of the combined use of sodium caseinate (CAS), commercial
phosphatidylcholine (PC), and modified PCs on the physical and oxidative stability of 70% fish
oil-in-water emulsions. Caffeic acid was covalently attached to both modified PCs (PCs originated
from soy and eggs) in order to increase the antioxidant activity of PCs and investigate the advantage
of bringing the antioxidant activity to the close proximity of the oil-water interface. Results showed
that oxidative stability was improved when part of the PC was substituted with modified soy PC or
egg PC. Emulsions containing a low concentration of modified PCs (10 wt.% of total PC) resulted in
a prooxidative effect on the formation of hydroperoxides compared to emulsions with free caffeic
acid. On the other hand, a decrease in the formation of volatile oxidation products was observed for
emulsions containing higher levels of modified PCs (60 wt.% of total PC) compared to the emulsions
with free caffeic acid added at its equivalent concentration. Increased concentrations of modified
PCs provided better oxidative stability in high-fat emulsions, independent of the modified PC type.
Moreover, when oxidation was initiated by producing singlet oxygen near a single oil droplet using a
focused laser, fluorescence imaging showed that the oxidation did not propagate from one oil droplet
to another oil droplet.Danish Council for Independent Research Technology
and Production Sciences for financing the project Mapping and Characterizing of Lipid Oxidation in
Emulsified Systems (MAPOX)DFFâ4184-0123A
Proteomic characterization of pilot scale hot-water extracts from the industrial carrageenan red seaweed Eucheuma denticulatum
Funding This work was supported by Innovation Fund Denmark (grant number 7045-00021B (PROVIDE) ) .Seaweeds have a long history as a resource for polysaccharides/hydrocolloids extraction for use in the food
industry due to their functionality as stabilizing agents. In addition to the carbohydrate content, seaweeds also
contains a significant amount of protein, which may find application in food and feed. Here, we present a novel
combination of transcriptomics, proteomics, and bioinformatics to determine the protein composition in two
pilot-scale extracts from Eucheuma denticilatum (Spinosum) obtained via hot-water extraction. Although the
quality of extracted protein appeared quite poor based on SDS-PAGE analysis, extracts were characterized by
qualitative and quantitative proteomics using LC-MS/MS and a de-novo transcriptome assembly for construction
of a suitable protein database. A novel concept of length-normalization for relative quantification of sub-optimal
protein extracts with partial, non-specific digestion is introduced and validated against conventional methods for
relative quantification of proteins. Despite a limited number of protein identifications due to poor protein
quality, our data suggest that the majority of quantified protein in the extracts (>75%) is constituted by merely
three previously uncharacterized proteins. Putative subcellular localization for the quantified proteins was
determined by bioinformatic prediction using several predictors, and by correlating with the expected copy
number from the transcriptome analysis, we find that the extracts appear highly enriched in extracellular proteins.
This implies that the extraction method used predominantly extracts extracellular proteins, and thus
appear ineffective for cellular disruption and subsequent release of intracellular proteins. Nevertheless, the
highly abundant proteins may be potential substrates for targeted hydrolysis and release of bioactive peptides.
Ultimately, this study highlight the potential of quantitative proteomics for characterization of alternative
protein sources intended for use in foods and evaluating protein extraction process efficiency through novel
combinations with bioinformatic analysis.Innovation Fund Denmark 7045-00021
Development of fish oil-loaded nano-microcapsules by co-axial electrospraying: physical characterization and oxidative stability
Physical and oxidative stability of fish oil-in-water emulsions stabilized with fish protein hydrolysates
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