Protein By-products Research Articles

Nutrient composition, digestible and metabolizable energy content, and prediction of energy for animal protein byproducts in finishing pig diets

Nutrient composition, digestible and metabolizable energy content, and prediction of energy for animal protein byproducts in finishing pig diets

Near-Infrared Spectroscopy and Geostatistical Analysis for Modeling Spatial Distribution of Analytical Constituents in Bulk Animal By-Product Protein Meals.

Control and inspection operations within the context of safety and quality assessment of bulk foods and feeds are not only of particular importance, they are also demanding challenges, given the complexity of food/feed production systems and the variability of product properties. Existing methodologies have a variety of limitations, such as high costs of implementation per sample or shortcomings in early detection of potential threats for human/animal health or quality deviations. Therefore, new proposals are required for the analysis of raw materials in situ in a more efficient and cost-effective manner. For this purpose, a pilot laboratory study was performed on a set of bulk lots of animal by-product protein meals to introduce and test an approach based on near-infrared (NIR) spectroscopy and geostatistical analysis. Spectral data, provided by a fiber optic probe connected to a Fourier transform (FT) NIR spectrometer, were used to predict moisture and crude protein content at each sampling point. Variographic analysis was carried out for spatial structure characterization, while ordinary Kriging achieved continuous maps for those parameters. The results indicated that the methodology could be a first approximation to an approach that, properly complemented with the Theory of Sampling and supported by experimental validation in real-life conditions, would enhance efficiency and the decision-making process regarding safety and adulteration issues.

Properties of Edible Films Made From Anchovy By-Product Proteins and Determination of Optimum Protein and Glycerol Concentration by the TOPSIS Method

ABSTRACTIn the present study, the physicochemical and mechanical properties of films made from anchovy (Engraulis encrasicholus) by-product proteins (ABPs) were characterized as a function of protein (3, 4, and 5%) and glycerol (30, 40, 50, and 60%) concentration. In particular, the thickness, color, transparency, water vapor permeability (WVP), solubility, oxygen permeability (OP), and mechanical properties of the films were measured, and generally, these properties were affected by both protein and glycerol concentration. The thickness, redness, WVP and solubility values of films increased, while their lightness and yellowness values decreased as protein concentration increased. Furthermore, lightness, yellowness, and elongation at break (EAB) values were found to increase at higher glycerol concentrations within ABP films, whereas tensile strength (TS) and elastic modulus (EM) values decreased. ABP films became more transparent with increase of glycerol concentration and decrease of protein concentration. The OP values of all films decreased depending on protein and glycerol concentration. The techniques for order performance by similarity to ideal solution (TOPSIS) method was used to determine optimum protein and glycerol concentrations. According to this method, an edible film containing 4% protein and 40% glycerol was the best film with a C value of 0.6665.

Nanomolar Hg2+ Detection Using β-Lactoglobulin-Stabilized Fluorescent Gold Nanoclusters in Beverage and Biological Media.

Owing to diverse functionalities and metal binding abilities, proteins have been proven to be promising ligands in the synthesis of gold nanoclusters (Au NCs). In this work, we explored β-lactoglobulin (β-Lg), a protein byproduct generated during cheese processing, as a biotemplate for fabrication of Au NCs by a facile and green method for the first time. The as-prepared Au NCs are water soluble and highly fluorescent and exhibit high sensitivity and selectivity for Hg2+ detection in aqueous solution. Interestingly, we found that the fluorescence of these Au NCs is stable either in a variety of complex matrixes or over a broad pH range (5.0-13.0) and therefore can be explored as a cell and animal imaging agent. More importantly, we demonstrated that the β-lactoglobulin-stabilized Au NCs (β-Lg-Au NCs) could serve as a sensor for the detection and quantification of Hg2+ in beverages, urine, and serum with high sensitivity.

Assessment on multilayer ultrafiltration membrane for fractionation of tilapia by-product protein hydrolysate with angiotensin I-converting enzyme (ACE) inhibitory activity

Abstract Ultrafiltration membrane is a convenient system to fractionate fish protein hydrolysate and recovery of peptide fraction with high ACE inhibitory activity. However, the limitation of applying membrane system in protein fractionation is its poor selectivity. This study aiming to assess the application of multilayer ultrafiltration in order to improve the selectivity of the tilapia by-product protein hydrolysate (TBH) separation by achieving higher amount of small peptides. Flat sheet regenerated cellulose (RC) membrane with molecular weight cut-off (MWCO) of 10 and 5 kDa were used for the separation of peptide mixtures. The membrane were arranged in the orientation of 10/5 kDa and 5/5 kDa, in which these two membrane were stacked together in one device. The performance of multilayer membrane were evaluated based on the permeate flux and peptide transmission, and compare with the single membrane system (5 and 10 kDa). The performance ultrafiltration membrane for fractionating TBH was studied under two different conditions (rotation speed and pH). The highest permeate flux and peptide transmission were obtained at membrane with pore size of 10 kDa (single), followed by 10/5 (multilayer), 5 (single) and 5/5 kDa (multilayer). Based on selectivity analysis, most permeate produced were composed of peptides lower than 1500 Da. When the smaller membrane’s pore size is used (5 kDa membrane and 5/5 multilayer membranes), the amount of small-sized peptide (

Effects of replacing marine fishmeal with graded levels of Tra Catfish by-product protein hydrolysate on the performance and meat quality of pigs

A feeding trial was carried out to evaluate the effects of replacing fish meal (FM) with Tra Catfish (Pangasius hypophthalmus) by-product protein hydrolysate (TPH) on performance and carcass quality in pigs. Forty crossbred castrated (Yorkshire x Landrace) male pigs with an initial average bodyweight of 22.8 ± 1.5 kg were allocated to 40 individual pens in a randomized complete block design with eight replications. The pigs were fed a control diet (TPH0) with FM as sole protein supplement. In the experimental diets, 100% (TPH100), 75% (TPH75), 50% (TPH50) and 25% (TPH25) of the crude protein (CP) from FM was replaced by the CP from TPH. The results showed no significant differences in average daily feed intake (ADFI) in all treatments during the growing and finishing phases. However, daily weight gain (ADG) was higher in TPH75 (655 g/day) and TPH100 (663 g/day) than in TPH0 (639 g/day). Feed conversion ratio (FCR) was improved with higher inclusion of TPH in the diets. Carcass yield and dressing percentage were not affected by treatments, but abdominal fat and backfat thickness were higher and in the loin-eye area lower in TPH100 compared with TPH0. Polyunsaturated fatty acids (PUFA), ether extract (EE) contents and meat colour values a* (redness) in the longissimus dorsi muscle increased with TPH replacement level. Feed costs were 10% lower in TPH100 compared with TPH0. In conclusion, replacing FM with TPH improved the performance, but resulted in an increase in backfat thickness and fat content of meat. However, because of reduced feed costs, complete replacement of FM would still be profitable for pig producers in Vietnam.Keywords: Backfat thickness, longissimus dorsi muscle, fatty acid, Pangasius hypophthalmus

Antioxidant Effect of Egg Yolk Peptides against Tert-butyl Hydroperoxide Induced Oxidative Stress in Caco-2 Colon Cancer Cells

Oxidative stress can damage lipids, proteins and DNA. The effect of hydrolysed, purified defatted egg yolk protein by-product (fraction EYGF-23) on oxidative stress in Caco-2 colon cancer epithelial cells was investigated for the first time. Caco-2 cells exposed to toxic 3 mM tert-butyl hydroperoxide (t-BHP) for 2 hours were protected when pretreated with 1.0 mg/ml EYGF-23 for 24 hours. The peptides inhibited intracellular reactive oxygen species (ROS) (60.0%) and malondialdehyde (MDA) (24.2 µg/ml) production, compared to cells treated with only t-BHP (75.3% and 32.2 µg/ml respectively). EYGF-23 inhibited caspase 3/7 activity in stressed cells, thereby protecting cells from induced caspase-dependent apoptosis. Further, total glutathione level and superoxide dismutase activity were significantly elevated to 0.29 µM and 55.10% respectively, in cells pretreated with EYGF-23, compared to t-BHP treatment alone (0.10 µM and 44.22 % respectively). Peptides WYGPD, TMFPSA and WIHNENQGF and hydrophobic amino acids tyrosine (Y) and tryptophan (W) contributed to cellular antioxidant activity against oxidative stress in colon epithelial cells and may have nutraceutical applications.

Effect of replacing marine fish meal with catfish (Pangasius hypophthalmus) by-product protein hydrolyzate on the growth performance and diarrhoea incidence in weaned piglets.

The present study consists of two experiments. In experiment 1, a total of 120 weaned piglets (Yorkshire × Landrace) (7.3 ± 1.9kg) were allocated to five treatments, and four replications (pens) with six piglets/pen. In experiment 2, 40 male pigs (23.0 ± 2.2kg) were allocated to five treatments and eight replications (individual pens). In both experiments, the control diet contained fish meal (FM) as the sole protein supplement (CPH0), while the experimental diets consisted of four different diets in which crude protein (CP) from FM in CPH0 was replaced by the CP from catfish (Pangasius hypophthalmus) by-product protein hydrolyzate (CPH) at four different levels: 100% (CPH100), 75% (CPH75), 50% (CPH50) and 25% (CPH25). The results in experiment 1 showed that the highest average daily gain (ADG) over the 5-week period after weaning was recorded for piglets on CPH100 (307g/day), and the lowest for piglets fed CPH0 (287g/day) (P < 0.01). Feed conversion ratio (FCR) was lower in CPH100 (1.43kg feed/kg gain) than in CPH0 (1.51kg feed/kg gain) (P < 0.01). The piglets fed CPH100 were less affected by diarrhoea (6.55%) than piglets fed the control diet CPH0 (17.3%) after weaning, and faecal scores were also lower. In experiment 2, ADG was lowest in CPH0, and the cost/gain in pigs fed CPH100 was lowest in both weaning and growing pigs. In conclusion, it is possible to replace up to 100% of the FM by CPH in diets for weaning and growing pigs, resulting in improved ADG and FCR, lower feed cost/gain as well as reduced diarrhoea incidence and improved faecal score.

Purification and identification of an angiotensin I-converting enzyme inhibitory peptide from cauliflower by-products protein hydrolysate

Cauliflower by-products (stems and leaves) are rich in leaf protein. Making full use of cauliflower by-products can not only alleviate the shortage of protein resources but also be beneficial to the environmental protection. This study sought to prepare and purify an angiotensin I-converting enzyme (ACE) inhibitory peptide from cauliflower by-products protein hydrolysate. Our result showed that the highest ACE inhibitory activity was observed in the Alcalase 2.4L hydrolysate among tested hydrolysates (pepsin, pancreatin, and Alcalase 2.4L). After purification, a dipeptide (Val-Trp) was identified, with a molecular weight of 304.1665Da. This peptide had a potent ACE inhibitory activity with IC50 of 31.30μM. Based on this purification process, approximately 42mg of this dipeptide was obtained from 1kg of fresh cauliflower by-products. Overall, the results suggest that cauliflower by-products protein can be used as an economical source of functional food material against hypertension.

The anti-inflammatory effect of a glycosylation product derived from the high hydrostatic pressure enzymatic hydrolysate of a flatfish byproduct.

In this study, flatfish byproducts were hydrolyzed by Protamex at high hydrostatic pressure and glycosylated with ribose to utilize the protein of flatfish byproducts as a nutraceutical. We investigated the anti-inflammatory effects of glycosylated fish byproduct protein hydrolysate (GFPH) and its anti-inflammatory mechanisms were elucidated in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophage. The results showed that GFPH suppresses LPS-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2) and expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) dose-dependently. The enzyme-linked immunosorbent assay (ELISA) kit clearly demonstrated that GFPH significantly reduced the production of pro-inflammatory cytokines such as, interleukin (IL)-6, interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1. Moreover, GFPH reduced nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) activation. These results indicate that the inhibitory effects of GFPH on LPS-induced NO and PGE2 production might be due to the suppression of the NF-κB and MAPKs signaling pathways. Therefore, these results suggest that flatfish byproducts are latent bioactive resources and GFPH may have potential as a therapeutic agent in the treatment of various inflammatory diseases.

Ảnh hưởng của beta-glucan và bột đạm thuỷ phân từ phụ phẩm cá tra (Pangasius hypophthalmus) trong khẩu phần đến tăng trưởng của heo con sau cai sữa

An experiment was conducted to evaluate the effects of combination of Catfish (Pangasius hypophthalmus) by-product protein hydrolysate (BTP) and Beta-glucan in diets on the performance of weaned piglets. The study was conducted according to a randomized complete design with 3 treatments and 4 replications (pen) as the experimental unit (3 piglets/pen). A total of 36 castrated male weaned piglets (Landrace x Yorkshire) at 26-28 days of age were allocated in the experiment. The control diet contained marine fish meal (BC) as the sole protein supplement diet (ĐC) and the others were two experimental diets in which crude protein (CP) from BC in ĐC was replaced by the CP from BTP and with (BTPB) or without (BTP) Beta-glucan supplementation. Results showed that, the highest and the lowest average daily gain (ADG) over the 5 week period after weaning were recorded for piglets on BTPB (393.3 g/day) and ĐC (315.7 g/day) diets. Average daily feed intake (ADFI) were of non significant differences (p >0.05) in all treatments. Therefore, feed conversion ratio (FCR) was lowest in BTPB (1.76 kg feed/kg gain) and highest in ĐC (2.18 kg feed/kg gain) (p

Biological activity of egg-yolk protein by-product hydrolysates obtained with the use of non-commercial plant protease

Enzymatic hydrolysis leads to improved functional and biological properties of protein by-products, which can be further used as nutraceuticals and protein ingredients for food applications. the present study evaluated AcE-inhibitory, antioxidant and immunostimulating activities in hydrolysates of egg-yolk protein by-product (YP), generated during industrial process of delipidation of yolk. the protein substrate was hydrolyzed using non-commercial protease from Asian pumpkin (Cucurbita ficifolia). the reaction was conducted in 0.1 M t ris-Hcl buffer (pH 8.0) at temperature of 37°c for 4 hours using different enzyme doses (100-1000 U/mg of substrate). the protein degradation was monitored by the determination of the degree of hydrolysis (DH), release of free amino groups (FAG) and by rP-HPLc. In the obtained hydrolysates we also evaluated biological activities. It was shown that the highest DH of substrate (46.6%) was obtained after 4h of reaction at the highest amount of enzyme. this hydrolysate exhibited antioxidant activity, including ferric ion reducing (FrAP) (56.41 μg Fe 2+ /mg), ferric ion chelating (695.76 μg Fe 2+ /mg) and DPPH free radical scavenging (0.89 μmol trolox eq /mg) as well as AcE-inhibitory (Ic 50 =837.75 μg/mL) activities. the research showed improved biological properties of enzymatically modified YP by-product.

Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins.

Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

Compositional features of cotton plant biomass fractions characterized by attenuated total reflection Fourier transform infrared spectroscopy

Cotton is one of the most important and widely grown crops in the world. In addition to natural textile fiber production as a primary purpose, it yields a high grade vegetable oil for human consumption and also carbohydrate fiber and protein byproducts for animal feed. In this work, attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy was applied to characterize the cotton plant biomass fractions. Furthermore, principal component analysis (PCA) of these ATR-FTIR spectra were performed to evaluate the similarity or dissimilarity of these biomass fractions from different parts of cotton plants, and the same plant parts collected between mid-season and pre-defoliation stages. These data revealed the more rapid accumulation of major carbohydrate components in main stems, roots, and branches than in petioles and leaf blades, increased our understanding of the cotton growth mechanism. PCA revealed that the ATR-FTIR spectra of cotton biomass fractions fell into two distinct clusters representing two types of cotton plant parts: Stem cluster (main stems, roots, branches, and petioles) and Leaf cluster (leaf blades, bracts, bur, and/or reproductive parts). Such clustering information could be helpful in selecting the FT-IR measurement parameters for assessing cotton plant growth, nutrition management, and biomass production.

Solid-state fermentation of Acanthogobius hastaprocessing by-products for the production of antioxidant protein hydrolysates with Aspergillus oryzae

Functional properties and antioxidative activity of a protein hydrolysate prepared from Acanthogobius hasta processing by-product protein during solid-state fermentation with Aspergillus oryzae were investigated. Overall, protease activity increased with the degree of hydrolysis (DH) decreased during solid-state fermentation. All the protein hydrolysate had excellent solubility, possessed interfacial properties, and varying degrees of antioxidant activity which were governed by their concentrations and DH, molecular weight distribution and amino acid composition. After 5 days fermentation, the DH of the protein hydrolysate was 31.23%. The protein hydrolysate had the highest total hydrophobic amino acid content, the highest DPPH scavenging activity, reducing power, and the chelating activity. The radical-scavenging activity of the hydrolysates at 6 mg/mL was 78.6%. The reducing power of protein hydrolysate at the range of 0-6 mg/mL was lower than that of BHA at the range of 0-60 µg/mL, while the chelating activity of APs was similar to that of BHA at the range of 0-60 µg/mL. Moreover, the protein hydrolysate showed good emulsifying and foaming properties over a wide pH range from 2 to 12. Therefore, solid state fermentation provided a suitable and low-cost method for converting Acanthogobius hasta processing by-product protein into antioxidant protein hydrolysates.

Vasopressin: the missing link for preeclampsia?

Preeclampsia is a devastating cardiovascular disorder of late pregnancy, affecting 5-7% of all pregnancies and claiming the lives of 76,000 mothers and 500,000 children each year. Various lines of evidence support a "tissue rejection" type reaction toward the placenta as the primary initiating event in the development of preeclampsia, followed by a complex interplay among immune, vascular, renal, and angiogenic mechanisms that have been implicated in the pathogenesis of preeclampsia beginning around the end of the first trimester. Critically, it remains unclear what mechanism links the initiating event and these pathogenic mechanisms. We and others have now demonstrated an early and sustained increase in maternal plasma concentrations of copeptin, a protein by-product of arginine vasopressin (AVP) synthesis and release, during preeclampsia. Furthermore, chronic infusion of AVP during pregnancy is sufficient to phenocopy essentially all maternal and fetal symptoms of preeclampsia in mice. As various groups have demonstrated interactions between AVP and immune, renal, and vascular systems in the nonpregnant state, elevations of this hormone are therefore positioned both in time (early pregnancy) and function to contribute to preeclampsia. We therefore posit that AVP represents a missing mechanistic link between initiating events and established midpregnancy dysfunctions that cause preeclampsia.

The Maillard reaction of a shrimp by-product protein hydrolysate: chemical changes and inhibiting effects of reactive oxygen species in human HepG2 cells.

Recently, much attention has been given to improving the antioxidant activity of protein hydrolysates via the Maillard reaction, but little is known about the cellular antioxidant activity of Maillard reaction products (MRPs) from protein hydrolysates. We first investigated chemical characterization and the cellular antioxidant activity of MRPs in a shrimp (Litopenaeus vannamei) by-product protein hydrolysate (SBH)-glucose system at 110 °C for up to 10 h of heating. Solutions of SBH and glucose were also heated alone as controls. The Maillard reaction greatly resulted in the increase of hydroxymethylfurfural (HMF) and browning intensity, high molecular weight fraction, and reduction of the total amino acid in SBH with the heating time, which correlated well with the free radical scavenging activity of MRPs. MRPs had stronger inhibiting effects on oxidative stress of human HepG2 cells than the original SBH, and its cellular antioxidant activity strongly correlated with free radical scavenging activity, but less affected by the browning intensity and HMF level. The caramelization of glucose partially affected the HMF level and free radical scavenging activity of MRPs, but it was not related to the cellular antioxidant activity. The cellular antioxidant activity of MRPs for 5 h of heating time appeared to reach a maximum level, which was mainly due to carbonyl ammonia condensation reaction. In conclusion, the Maillard reaction is a potential method to increase the cellular antioxidant activity of a shrimp by-product protein hydrolysate, but the higher HMF levels and the lower amino acid content in MRPs should also be considered.

Multifunctional peptides derived from an egg yolk protein hydrolysate: isolation and characterization.

An egg yolk protein by-product following ethanol extraction of phospholipids (YP) was hydrolyzed with pepsin to produce and identify novel peptides that revealed antioxidant, ACE inhibitory and antidiabetic (α-glucosidase and DPP-IV inhibitory) activities. The peptic hydrolysate of YP was fractionated by ion-exchange chromatography and reversed-phase high-pressure liquid chromatography. Isolated peptides were identified using mass spectrometry (MALDI-ToF) and the Mascot Search Results database. Four peptides of MW ranging from 1,210.62 to 1,677.88 Da corresponded to the fragments of Apolipoprotein B (YINQMPQKSRE; YINQMPQKSREA), Vitellogenin-2 (VTGRFAGHPAAQ) and Apovitellenin-1 (YIEAVNKVSPRAGQF). These peptides were chemically synthesized and showed antioxidant, ACE inhibitory or/and antidiabetic activities. Peptide YIEAVNKVSPRAGQF exerted the strongest ACE inhibitory activity, with IC50 = 9.4 µg/mL. The peptide YINQMPQKSRE showed the strongest DPPH free radical scavenging and DPP-IV inhibitory activities and its ACE inhibitory activity (IC50) reached 10.1 µg/mL. The peptide VTGRFAGHPAAQ revealed the highest α-glucosidase inhibitory activity (IC50 = 365.4 µg/mL). A novel nutraceutical effect for peptides from an egg yolk hydrolysate was shown.

Incorporation of Groundnut Meal in Selected Products after Removal of Aflatoxin

KEYWORDS Aflatoxin. Groundnut Meal. Malnutrition. Novel Protein Source. Value Addition ABSTRACT Groundnut meal is the high protein by-product remaining after commercial extraction of peanut oil. Groundnut meal applications are limited because of typical high concentrations of aflatoxin. In the present study technology was developed to prepare protein rich powder from an oil extracted groundnut. To make the meal free from aflatoxin four treatments were employed viz. ether treatment, heat treatment, acid-alkali treatment and homestead acid-alkali treatment. After each treatment, the powder was subjected to analysis of protein and aflatoxin and acceptability for sensory characteristics. A reduction ranged from 17.86 to 100 percent of aflatoxin and 29.17 to 70.47 percent of protein. A comparative evaluation of four powders indicated that homestead acid alkali treatment is free from aflatoxin and containing 10.09gm of protein. This powder was incorporated in three products, that is, batti, besan laddu, and sweet biscuits at 35 and 50 percent level. Acceptability was assessed on 9 point hedonic rating scale. The mean overall acceptability of reference, 35 percent and 50 percent incorporated batti were 8.1, 7.2 and 6.3, besan laddu 8.0, 7.3 and 6.8 sweet biscuits 7.6, 7.4 and 6.5 respectively, revealing that the developed powder is acceptable at moderate level in various products. No significant difference (P>0.05) was found between reference and 35 percent incorporated product and between 35 and 50 percent incorporated products. However, the 50 percent incorporated product scored significantly lower than the reference, specifically for colour and appearance. The study concluded that aflatoxin can be removed from groundnut meal and further, can be used in different recipes as protein source.

Egg-yolk protein by-product as a source of ACE-inhibitory peptides obtained with using unconventional proteinase from Asian pumpkin (Cucurbita ficifolia).

Peptides with specific biological activity can be used in pharmaceutical, cosmetic or food industries. Because of their potential role as physiological modulators, as well as theirhigh safety profile, they can be used as natural pharmacological compounds or functional food ingredients. The development of biotechnological solutions to obtain peptides with desired biological activity is already in progress. Studies in this area are focused on using unconventional highly specific enzymes and more efficient methods developed to conduct food process technologies. Natural peptides have many advantages. They are mainly toxicologically safe, have wide spectra of therapeutic actions, exhibit less side effects compared to synthetic drugs and are more efficiently absorbed in the intestinal tract. The complexity of operation of large scale technologies and high cost of purification techniques are limiting factors to the commercialization of food-derived bioactive peptides. Research on the isolation of bioactive peptides in order to reduce the processing time and costs is continuously developing. Bioactive peptides can also be released from protein by-products of the food industry, which reduce the substrate expense and production cost as well as provide the added advantage of an efficient waste disposal. Moreover, proteins as precursors of food-derived peptides are well-tolerated by the human body and therefore their application in drug development may reduce costs and duration of toxicological studies during research, development and clinical trials.