Application Of Protein Hydrolysates Research Articles

Unravelling the biostimulant activity of a protein hydrolysate in lettuce plants under optimal and low N availability: a multi-omics approach.

The application of protein hydrolysates (PH) biostimulants is considered a promising approach to promote crop growth and resilience against abiotic stresses. Nevertheless, PHs bioactivity depends on both the raw material used for their preparation and the molecular fraction applied. The present research aimed at investigating the molecular mechanisms triggered by applying a PH and its fractions on plants subjected to nitrogen limitations. To this objective, an integrated transcriptomic-metabolomic approach was used to assess lettuce plants grown under different nitrogen levels and treated with either the commercial PH Vegamin® or its molecular fractions PH1(>10 kDa), PH2 (1-10 kDa) and PH3 (<1 kDa). Regardless of nitrogen provision, biostimulant application enhanced lettuce biomass, likely through a hormone-like activity. This was confirmed by the modulation of genes involved in auxin and cytokinin synthesis, mirrored by an increase in the metabolic levels of these hormones. Consistently, PH and PH3 upregulated genes involved in cell wall growth and plasticity. Furthermore, the accumulation of specific metabolites suggested the activation of a multifaceted antioxidant machinery. Notwithstanding, the modulation of stress-response transcription factors and genes involved in detoxification processes was observed. The coordinated action of these molecular entities might underpin the increased resilience of lettuce plants against nitrogen-limiting conditions. In conclusion, integrating omics techniques allowed the elucidation of mechanistic aspects underlying PH bioactivity in crops. Most importantly, the comparison of PH with its fraction PH3 showed that, except for a few peculiarities, the effects induced were equivalent, suggesting that the highest bioactivity was ascribable to the lightest molecular fraction.

Enhancing the performance of leafy greens under nutrient deficiency and salinity stress through the application of protein hydrolysates

Enhancing the performance of leafy greens under nutrient deficiency and salinity stress through the application of protein hydrolysates

Growth of Tea Nursery Plants as Influenced by Different Rates of Protein Hydrolysate Derived from Chicken Feathers

The conversion of chicken feathers, generated annually worldwide on a large scale as a by-product of the poultry industry into value-added products, has economic and environmental benefits. Protein hydrolysate produced from feathers has attracted significant attention in agriculture as a potential plant growth stimulant. Therefore, a study was established with the aim to produce and characterize chicken feather protein hydrolysate (CFPH) and investigate the effects of this product on the early growth of nursery tea plants. Alkaline hydrolysis was used to produce CFPH with the yield of 165 mg amino acids per gram of feathers. Then, the produced CFPH was applied on nursery tea plants as a soil drench at different doses (0.5, 1, 2, 3, and 4 g L−1) in 2-week intervals until the 10th application. Commercially available fish protein hydrolysate (FPH) was included as a treatment to compare the effects with CFPH. The treatments were arranged in a completely randomized block design with three replications. CFPH and FPH significantly improved the shoot and root growth parameters. Plant height (+98%), leaf number (+61%), shoot dry biomass (+128%), root length (+94%), root surface area (+15%), and root dry biomass (+152%) were significantly increased by the application of CFPH (2 g L−1 dose) compared to control. Although the highest CFPH dosage (4 g L−1) showed a reduction in growth parameters, the values obtained were similar or higher than the untreated control plants. The chlorophyll content (a, b, and total) was enhanced by the CFPH dosage of 1 g L−1, whereas the highest photosynthetic rate was recorded in the CFPH 3 g L−1 treatment. The application of protein hydrolysates (PH) did not positively influence stomatal conductance and intercellular CO2 concentration. Leaf nitrogen, phosphorous, manganese, and copper were positively affected by the CFPH application. The effect of CFPH on growth parameters was more pronounced than FPH. Our findings reveal that CFPH produced by alkaline hydrolysis could be used as a growth booster in raising vigorous tea nursery plants, which are most suitable for field planting and subsequently higher yields.

Foliar application of plant-based biostimulants improve yield and upgrade qualitative characteristics of processing tomato

Tomato (Solanum lycopersicum L.) is a diffused worldwide vegetable. Great amounts of fertilizers are often applied for increasing yield and quality, without considering the negative effect on the environment. A possible perspective for reducing this risk is to raise the nitrogen use efficiency (NUE) through the use of plant biostimulants, which also improve yield and quality concomitantly. The aim of the current study was to verify the potential beneficial effect of three vegetal-based biostimulants on agronomical, qualitative and nitrogen use efficiency of a processing tomato crop. The experiment provided three biostimulants (an extract of brown seaweed [SwE], a legume-derived protein hydrolysate [LDPH] and a tropical plant extract). The following assessments were carried out: marketable and unmarketable yields, mean fruits weight, firmness, pH, total soluble solids (TSS), colour parameters (a/b), hydrophilic antioxidant activity (HAA), lipophilic antioxidant activity (LAA), total ascorbic acid content (AsA), total phenols, nitrate and total nitrogen content, nitrogen use efficiency, N-uptake efficiency, and N-utilization. The foliar application of biostimulants especially protein hydrolysates and seaweed extract significantly affected the marketable yield with an average increase of 18.3% over the control and 41.3% average decrease in unmarketable yield. The N-use and N-uptake efficiency followed a similar trend, with biostimulants boosting it higher than control, +18.4% and +59.3%, respectively; the nitrogen content was also higher in fruits of sprayed plants: +21.3% over control. This finding also reflects on higher dry matter accumulation and firmness in fruits of treated plants (+10.9% and +14.1% over control, respectively). The biostimulants application, in particular SwE and LDPH, also boosted TSS (+12.8%), the a/b colour ratio (+7.5%), HAA and AsA (9.8% and 114.6%, respectively). Therefore, the legume-derived protein hydrolysates and extract of brown seaweed Ecklonia maxima seem a good sustainable approach to improve yield and quality of tomato for canning industries.&#x0D; Highlights - The effects of three plant-based biostimulants on yield and quality of processing tomato was explored. - Application of protein hydrolysates and seaweed extract improve marketable yield. - The biostimulants had different effect on nutritional and functional quality of tomato. - Hydrophilic antioxidant activity and ascorbic acid content increased under protein hydrolysate application.

The effect of the commercial fish gelatin protein hydrolysate on rainbow trout (Oncorhynchus mykiss) fillet quality

Abstract Willing to increase the shelf life of the food matrix, studies regarding new preservations methods are developed to preserve fish deterioration. The application of natural additives as preservatives is increasingly common, with a current emphasis on the growing use of protein hydrolysates, in substitution to artificial ones. These compounds have been the subject of recent studies, focusing on determining their functional properties and the best form of applying peptide chains. The present study aimed to evaluate the effects of the protein hydrolysate obtained by the enzymatic hydrolysis of commercial fish gelatin added to rainbow trout fillets (Oncorhynchus mykiss) packed under vacuum and maintained under refrigeration. The fillets were distributed into three sample groups (controls and hydrolysate addition at 1:10 and 1:1 ratios). Microbiological and physico-chemical assessments were carried out. The results were compared and correlations observed regarding fish preservation assessments. A relationship between pH, redox potential and N-TVB was verified when compared to microbial development, especially with regard to psychrotrophic aerobic heterotrophic bacteria count. It was concluded that the application of protein hydrolysate as an additive is promising and can be effective in the control of food quality and maintenance of freshness for a longer period.

Эффективность применения белковых гидролизатов птице

Эффективность применения белковых гидролизатов птице

Application of Protein Hydrolysates from Defatted Walnut Meal in High-Gravity Brewing to Improve Fermentation Performance of Lager Yeast.

Protein hydrolysates were prepared from an industrially defatted walnut meal (DWMPH) by enzymolysis employing Neutrase, Protamex, and Flavorzyme, respectively, with/without ultrasonic treatment. The effects of DWMPH supplementations on fermentation performance of lager yeast in high-gravity brewing were investigated. Results showed that ultrasonic-assisted enzymolysis simultaneous treatment (UAE) and ultrasonic pretreatment followed by enzymolysis (UPE) significantly increased degree of hydrolysis (DH) by 1.43 times and 0.71 times of traditional enzymolysis (TE) at least, respectively, Protamex treatment exhibited higher DH (13.3-32.8%) than Neutrase (9.2-25.3%) or Flavorzyme (11.8-28.7%). Compared with control, DWMPH supplementations prepared by UAE using Protamex (UAE-P), Neutrase (UAE-N), or Flavorzyme (UAE-F) significantly improved fermentation performance of lager yeast, especially for UAE-P with the highest major fractions of Mw < 1kDa, increased wort fermentability and ethanol production by 15% and 17%, respectively, while UAE-F with the highest major fractions of Mw > 3kDa obviously improved the foam stability of final beers. Furthermore, DWMPH supplementations significantly increased yeast growth and cell viability, promoted glycogen and trehalose accumulation, upregulated stress markers HSP12 and SSA3 expression in yeast cells, improved the formation of higher alcohols and esters, and increased the ratio of higher alcohol to ester indicating a better balanced taste of final beers.

Effect of deamidation-induced modification on umami and bitter taste of wheat gluten hydrolysates.

Bitter taste is the main limiting factor for various applications of protein hydrolysates. Frequently used physicochemical methods for debittering protein hydrolysates come with some undesired side effects. Deamidation-induced modification would be a very promising technique to improve the flavor of wheat gluten hydrolysates (WGHs). This study was designed to determine the effect of deamidation with certain enzymes or acid treatment on the chemical composition, bitterness and umami properties of WGHs. The difference between umami peptide and free glutamic acid on the suppression of bitterness is emphatically discussed. The optimal scheme is proposed based on the flavor of WGHs and the yield of peptides. The generation of umami substances suppressed bitter signal transduction. When the content of umami substances was relatively high, the umami-enhancing properties of umami peptides were obviously effective. The intensity of umami taste was high enough to further suppress bitter taste in the course of neurocognitive functioning. When WGHs were treated with Glutaminase for 180 min, the umami taste score increased from 1.62 to 4.27 and the bitter taste score decreased from 1.33 to 0.65. © 2016 Society of Chemical Industry.

Protein Hydrolysates and Biopeptides: Production, Biological Activities, and Applications in Foods and Health Benefits. A Review.

In recent years, a great deal of interest has been expressed regarding the production, characterization, and applications of protein hydrolysates and food-derived biopeptides due to their numerous beneficial health effects. In this regard, research is mainly focused on investigating the therapeutic potential of these natural compounds. Based on their amino acids composition, sequences, hydrophobicity, and length, peptides released from food proteins, beyond their nutritional properties, can exhibit various biological activities including antihypertensive, antioxidative, antithrombotic, hypoglycemic, hypocholesterolemic, and antibacterial activities among others. Protein hydrolysates are essentially produced by enzymatic hydrolysis of whole protein sources by appropriate proteolytic enzymes under controlled conditions, followed by posthydrolysis processing to isolate desired and potent bioactive peptides from a complex mixture of active and inactive peptides. Therefore, because of their human health potential and safety profiles, protein hydrolysates and biopeptides may be used as ingredients in functional foods and pharmaceuticals to improve human health and prevent diseases. In this review, we have focused on the major variables influencing the enzymatic process of protein hydrolysates production. The biological properties of protein hydrolysates will be described as well as their applications in foods and health benefits.

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis.

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances.