The Protein Composition of the Digestive Fluid from the Venus Flytrap Sheds Light on Prey Digestion Mechanisms*

Science.gov (United States)

Schulze, Waltraud X.; Sanggaard, Kristian W.; Kreuzer, Ines; Knudsen, Anders D.; Bemm, Felix; Thøgersen, Ida B.; Bräutigam, Andrea; Thomsen, Line R.; Schliesky, Simon; Dyrlund, Thomas F.; Escalante-Perez, Maria; Becker, Dirk; Schultz, Jörg; Karring, Henrik; Weber, Andreas; Højrup, Peter; Hedrich, Rainer; Enghild, Jan J.

2012-01-01

The Venus flytrap (Dionaea muscipula) is one of the most well-known carnivorous plants because of its unique ability to capture small animals, usually insects or spiders, through a unique snap-trapping mechanism. The animals are subsequently killed and digested so that the plants can assimilate nutrients, as they grow in mineral-deficient soils. We deep sequenced the cDNA from Dionaea traps to obtain transcript libraries, which were used in the mass spectrometry-based identification of the proteins secreted during digestion. The identified proteins consisted of peroxidases, nucleases, phosphatases, phospholipases, a glucanase, chitinases, and proteolytic enzymes, including four cysteine proteases, two aspartic proteases, and a serine carboxypeptidase. The majority of the most abundant proteins were categorized as pathogenesis-related proteins, suggesting that the plant's digestive system evolved from defense-related processes. This in-depth characterization of a highly specialized secreted fluid from a carnivorous plant provides new information about the plant's prey digestion mechanism and the evolutionary processes driving its defense pathways and nutrient acquisition. PMID:22891002

In Vitro Digestibility of Rapeseed and Bovine Whey Protein Mixtures.

Science.gov (United States)

Joehnke, Marcel Skejovic; Rehder, Alina; Sørensen, Susanne; Bjergegaard, Charlotte; Sørensen, Jens Christian; Markedal, Keld Ejdrup

2018-01-24

Partial replacement of animal protein sources with plant proteins is highly relevant for the food industry, but potential effects on protein digestibility need to be established. In this study, the in vitro protein digestibility (IVPD) of four protein sources and their mixtures (50:50 w/w ratio) was investigated using a transient pepsin hydrolysis (1 h) followed by pancreatin (1 h). The protein sources consisted of napin-rich rapeseed (Brassica napus L.) protein concentrates (RPCs; RP1, RP2) prepared in pilot scale and major bovine whey proteins (WPs; α-LA, alpha-lactalbumin; β-LG, beta-lactoglobulin). IVPD of individual protein sources was higher for WPs compared to RPCs. The RP2/β-LG mixture resulted in an unexpected high IVPD equivalent to β-LG protein alone. Protein mixtures containing RP1 showed a new IVPD response type due to the negative influence of a high trypsin inhibitor activity (TIA) level. Improved IVPD of RP1 alone and in protein mixtures was obtained by lowering the TIA level using dithiothreitol (DTT). These results showed that napin-rich protein products prepared by appropriate processing can be combined with specific WPs in mixtures to improve the IVPD.

Measurement of protein digestibility in humans by a dual-tracer method.

Science.gov (United States)

Devi, Sarita; Varkey, Aneesia; Sheshshayee, M S; Preston, Thomas; Kurpad, Anura V

2018-06-01

Recent evaluations of the risk of dietary protein deficiency have indicated that protein digestibility may be a key limiting factor in the provision of indispensable amino acids (IAAs), particularly for vulnerable populations living in challenging environments where intestinal dysfunction may exist. Since the digestion of protein occurs only in the small intestine, and the metabolic activity of colonic bacteria confounds measurements at the fecal level, there is a need to develop noninvasive protein digestibility measurements at the ileal level. We used a dual-tracer method with stable isotopes to characterize the digestibility of uniformly labeled [13C]-spirulina protein as a standard protein, in comparison to a mixture of 2H-labeled crystalline amino acids, and then demonstrated the use of this standard protein to measure the digestibility of selected legumes (chick pea and mung bean) through the use of proteins that were intrinsically labeled with 2H. The digestibility of uniformly labeled [13C]-spirulina was first measured in 6 healthy volunteers (3 males and 3 females) by feeding it along with a standard mixture of 2H-labeled amino acids, in a dual-tracer, plateau-fed test meal approach. Next, intrinsically labeled legume protein digestibility was studied with a similar dual-tracer approach, with uniformly labeled [13C]-spirulina as the standard, when processed differently before consumption. The average digestibility of IAA in spirulina protein was 85.2%. The average IAA digestibility of intrinsically 2H-labeled chick pea and mung bean protein was 56.6% and 57.7%, respectively. Dehulling of mung bean before ingestion increased the average IAA digestibility by 9.9% in comparison to whole mung bean digestibility. An innovative, minimally invasive "dual-stable-isotope" method was developed to measure protein digestibility, in which the ingestion of an intrinsically 2H-labeled test protein along with a 13C-labeled standard protein of known digestibility allows

Immunohistochemical localization of translationally controlled tumor protein in the mouse digestive system.

Science.gov (United States)

Sheverdin, Vadim; Jung, Jiwon; Lee, Kyunglim

2013-09-01

Translationally controlled tumor protein (TCTP) is a housekeeping protein, highly conserved among various species. It plays a major role in cell differentiation, growth, proliferation, apoptosis and carcinogenesis. Studies reported so far on TCTP expression in different digestive organs have not led to any understanding of the role of TCTP in digestion, so we localized TCTP in organs of the mouse digestive system employing immunohistochemical techniques. Translationally controlled tumor protein was found expressed in all organs studied: tongue, salivary glands, esophagus, stomach, small and large intestines, liver and pancreas. The expression of TCTP was found to be predominant in epithelia and neurons of myenteric nerve ganglia; high in serous glands (parotid, submandibular, gastric, intestinal crypts, pancreatic acini) and in neurons of myenteric nerve ganglia, and moderate to low in epithelia. In epithelia, expression of TCTP varied depending on its type and location. In enteric neurons, TCTP was predominantly expressed in the processes. Translationally controlled tumor protein expression in the liver followed porto-central gradient with higher expression in pericentral hepatocytes. In the pancreas, TCTP was expressed in both acini and islet cells. Our finding of nearly universal localization and expression of TCTP in mouse digestive organs points to the hitherto unrecognized functional importance of TCTP in the digestive system and suggests the need for further studies of the possible role of TCTP in the proliferation, secretion, absorption and neural regulation of the digestive process and its importance in the physiology and pathology of digestive process. © 2013 Anatomical Society.

Relationship between Molecular Structure Characteristics of Feed Proteins and Protein Digestibility and Solubility

Directory of Open Access Journals (Sweden)

Mingmei Bai

2016-08-01

Full Text Available The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller’s dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as α-helices and β-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area of feed proteins were correlated with their the in vitro digestibility and solubility (p≤0.003; moreover, the relatively quantitative amounts of α-helices, random coils, and α-helix to β-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility (p≤0.004. On the other hand, the percentage of β-sheet structures was negatively correlated with protein in vitro digestibility (p<0.001 and solubility (p = 0.002. These results demonstrate that the molecular structure characteristics of feed proteins are closely related to their in vitro digestibility at 28 h and solubility. Furthermore, the α-helix-to-β-sheet ratio can be used to predict the nutritional value of feed proteins.

Protein digestion in ruminants

African Journals Online (AJOL)

a balance between synthesis and hydrolysis. Aside from .... be used to follow the synthesis of this protein fraction. (Clarke, 1977a) .... form of digestive enzymes, urea and ammonia (Egan, ..... decreasing urine-nitrogen excretion (Thornton, Bird,.

Roles of F-box proteins in human digestive system tumors (Review).

Science.gov (United States)

Gong, Jian; Lv, Liang; Huo, Jirong

2014-12-01

F-box proteins (FBPs), the substrate-recognition subunit of E3 ubiquitin (Ub) ligase, are the important components of Ub proteasome system (UPS). FBPs are involved in multiple cellular processes through ubiquitylation and subsequent degradation of their target proteins. Many studies have described the roles of FBPs in human cancers. Digestive system tumors account for a large proportion of all the tumors, and their mortality is very high. This review summarizes for the first time the roles of FBPs in digestive system tumorige-nesis and tumor progression, aiming at finding new routes for the rational design of targeted anticancer therapies in digestive system tumors.

Mass spectrometry compatible surfactant for optimized in-gel protein digestion.

Science.gov (United States)

Saveliev, Sergei V; Woodroofe, Carolyn C; Sabat, Grzegorz; Adams, Christopher M; Klaubert, Dieter; Wood, Keith; Urh, Marjeta

2013-01-15

Identification of proteins resolved by SDS-PAGE depends on robust in-gel protein digestion and efficient peptide extraction, requirements that are often difficult to achieve. A lengthy and laborious procedure is an additional challenge of protein identification in gel. We show here that with the use of the mass spectrometry compatible surfactant sodium 3-((1-(furan-2-yl)undecyloxy)carbonylamino)propane-1-sulfonate, the challenges of in-gel protein digestion are effectively addressed. Peptide quantitation based on stable isotope labeling showed that the surfactant induced 1.5-2 fold increase in peptide recovery. Consequently, protein sequence coverage was increased by 20-30%, on average, and the number of identified proteins saw a substantial boost. The surfactant also accelerated the digestion process. Maximal in-gel digestion was achieved in as little as one hour, depending on incubation temperature, and peptides were readily recovered from gel eliminating the need for postdigestion extraction. This study shows that the surfactant provides an efficient means of improving protein identification in gel and streamlining the in-gel digestion procedure requiring no extra handling steps or special equipment.

Variation in In Vitro Digestibility of Barley Protein

DEFF Research Database (Denmark)

Buchmann, N. B.

1979-01-01

impaired digestibilities; these findings were partially verified in a repeated field trial, but were not confirmed in vivo. In vitro digestibilities of barleys grown in pots at various N-levels were positively correlated with protein or hordein content. In vitro digestibility was negatively correlated...

Soluble arabinoxylan alters digesta flow and protein digestion of red meat-containing diets in pigs.

Science.gov (United States)

Zhang, Dagong; Williams, Barbara A; Mikkelsen, Deirdre; Li, Xiuhua; Keates, Helen L; Lisle, Allan T; Collins, Helen M; Fincher, Geoffrey B; Bird, Anthony R; Topping, David L; Gidley, Michael J; Bryden, Wayne L

2015-09-01

The aim of this study was to investigate how a moderate increase in dietary meat content combined (or not) with soluble fibre would influence protein digestion as well as digesta characteristics and flow. Four groups of pigs were fed Western-style diets (high-protein/high-fat) containing two types of barbecued red meat, one with and one without a wheat arabinoxylan-rich fraction. After 4 wk, digesta samples were collected from small and large intestinal sites and analyzed for protein, amino acids, dry matter, and acid-insoluble ash. Tissue samples were also collected from each site. Arabinoxylan consumption led to somewhat lower apparent protein digestibility within the small and large intestines as well as shorter mean retention times. This suggests that the lowered protein digestibility is due, at least partly, to shorter access time to digestive proteases and absorptive surfaces. Additionally, digesta mass was higher in pigs fed arabinoxylan while dry matter (%) was lower, indicating an increased digesta water-holding capacity due to the presence of a soluble dietary fiber. Data showed that solubilized wheat arabinoxylan provides potential health benefits through decreased protein digestibility, increased digesta mass, and reduced mean retention time, even for diets with a moderately higher protein content. These factors are associated with efficiency of digestion and satiety, both of which have implications for prevention of obesity and other health disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Isotopic Changes During Digestion: Protein

Science.gov (United States)

Tuross, N.

2013-12-01

Nutrient and hydrological inputs traverse a complicated route of pH, enzymatic and cellular processes in digestion in higher animals. The end products of digestion are the starting products for biosynthesis that are often used to interpret past life-ways. Using an artificial gut system, the isotopic changes (dD, d18O, d13C and d15N) of protein are documented. Three separate protein sources are subjected to the conditions, chemical and enzymatic, found in the stomach and upper small intestine with only a small shift in the oxygen isotopic composition of the proteins observed. Middle to lower small intestine parameters produced both greater isotopic effects and significantly lower molecular weight products. The role of the gastric enterocyte and the likely involvement of the internal milieu of this cell in the isotopic composition of amino acids that are transported to the liver are reported.

In vitro versus in vivo protein digestibility techniques for calculating PDCAAS (protein digestibility-corrected amino acid score) applied to chickpea fractions.

Science.gov (United States)

Tavano, Olga Luisa; Neves, Valdir Augusto; da Silva Júnior, Sinézio Inácio

2016-11-01

Seven different in vitro methods to determine the protein digestibility for chickpea proteins were considered and also the application of these methodologies for calculating PDCAAS (protein digestibility-corrected amino acid score), seeking their correlations with the in vivo methodology. In vitro digestibility of raw and heated samples were determined using pepsin-pancreatin hydrolysis, considering soluble nitrogen via Kjeldahl (ppKJ) and hydrolysed peptide linkages using trinitrobenzenesulfonic acid and o-phthaldialdehyde. In vitro digestibility was also determined using trypsin, chymotrypsin and peptidase (3-Enz) or trypsin, chymotrypsin, peptidase and pronase solution (4-Enz). None of the correlations between in vitro and in vivo digestibilities were significant (at p<0.0500), but, strong correlations were observed between PDCAAS calculated by in vitro and in vivo results. PDCAAS-ppKJ, PDCAAS-3-Enz and PDCAAS-4-Enz presented the highest correlations with in vivo method, r=0.9316, 0.9442 and 0.9649 (p<0.0500), respectively. The use of in vitro methods for calculating PDCAAS may be promising and deserves more discussions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Trypsin immobilization in ordered porous polymer membranes for effective protein digestion

International Nuclear Information System (INIS)

Qiao, Juan; Kim, Jin Yong; Wang, Yuan Yuan; Qi, Li; Wang, Fu Yi; Moon, Myeong Hee

2016-01-01

Fast and effective protein digestion is a vital process for mass spectrometry (MS) based protein analysis. This study introduces a porous polymer membrane enzyme reactor (PPMER) coupled to nanoflow liquid chromatography-tandem MS (nLC-ESI-MS/MS) for on-line digestion and analysis of proteins. Poly (styrene-co-maleic anhydride) (PS-co-MAn) was fabricated by the breath figure method to make a porous polymer membrane in which the MAn group was covalently bound to enzyme. Based on this strategy, microscale PPMER (μPPMER) was constructed for on-line connection with the nLC-ESI-MS/MS system. Its capability for enzymatic digestion with bovine serum albumin (BSA) was evaluated with varied digestion periods. The on-line proteolysis of BSA and subsequent analysis with μPPMER-nLC-ESI-MS/MS revealed that peptide sequence coverage increased from 10.3% (digestion time 10 min) to 89.1% (digestion time 30 min). μPPMER can efficiently digest proteins due to the microscopic confinement effect, showing its potential application in fast protein identification and protease immobilization. Applications of on-line digestion using μPPMER with human plasma and urinary proteome samples showed that the developed on-line method yielded equivalent or better performance in protein coverage and identified more membrane proteins than the in-solution method. This may be due to easy accommodation of hydrophobic membrane proteins within membrane pores. - Highlights: • A porous polymer membrane enzyme reactor was developed. • Breath figure method was used for the fabrication of porous polymer membrane. • The enzyme reactor was coupled to nLC-ESI-MS/MS for proteins on-line digestion.

Trypsin immobilization in ordered porous polymer membranes for effective protein digestion

Energy Technology Data Exchange (ETDEWEB)

Qiao, Juan [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190 (China); Kim, Jin Yong [Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seoul 120-749 (Korea, Republic of); Wang, Yuan Yuan [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190 (China); Qi, Li, E-mail: qili@iccas.ac.cn [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190 (China); Wang, Fu Yi [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190 (China); Moon, Myeong Hee, E-mail: mhmoon@yonsei.ac.kr [Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seoul 120-749 (Korea, Republic of)

2016-02-04

Fast and effective protein digestion is a vital process for mass spectrometry (MS) based protein analysis. This study introduces a porous polymer membrane enzyme reactor (PPMER) coupled to nanoflow liquid chromatography-tandem MS (nLC-ESI-MS/MS) for on-line digestion and analysis of proteins. Poly (styrene-co-maleic anhydride) (PS-co-MAn) was fabricated by the breath figure method to make a porous polymer membrane in which the MAn group was covalently bound to enzyme. Based on this strategy, microscale PPMER (μPPMER) was constructed for on-line connection with the nLC-ESI-MS/MS system. Its capability for enzymatic digestion with bovine serum albumin (BSA) was evaluated with varied digestion periods. The on-line proteolysis of BSA and subsequent analysis with μPPMER-nLC-ESI-MS/MS revealed that peptide sequence coverage increased from 10.3% (digestion time 10 min) to 89.1% (digestion time 30 min). μPPMER can efficiently digest proteins due to the microscopic confinement effect, showing its potential application in fast protein identification and protease immobilization. Applications of on-line digestion using μPPMER with human plasma and urinary proteome samples showed that the developed on-line method yielded equivalent or better performance in protein coverage and identified more membrane proteins than the in-solution method. This may be due to easy accommodation of hydrophobic membrane proteins within membrane pores. - Highlights: • A porous polymer membrane enzyme reactor was developed. • Breath figure method was used for the fabrication of porous polymer membrane. • The enzyme reactor was coupled to nLC-ESI-MS/MS for proteins on-line digestion.

Quantitative proteomics reveals the kinetics of trypsin-catalyzed protein digestion.

Science.gov (United States)

Pan, Yanbo; Cheng, Kai; Mao, Jiawei; Liu, Fangjie; Liu, Jing; Ye, Mingliang; Zou, Hanfa

2014-10-01

Trypsin is the popular protease to digest proteins into peptides in shotgun proteomics, but few studies have attempted to systematically investigate the kinetics of trypsin-catalyzed protein digestion in proteome samples. In this study, we applied quantitative proteomics via triplex stable isotope dimethyl labeling to investigate the kinetics of trypsin-catalyzed cleavage. It was found that trypsin cleaves the C-terminal to lysine (K) and arginine (R) residues with higher rates for R. And the cleavage sites surrounded by neutral residues could be quickly cut, while those with neighboring charged residues (D/E/K/R) or proline residue (P) could be slowly cut. In a proteome sample, a huge number of proteins with different physical chemical properties coexists. If any type of protein could be preferably digested, then limited digestion could be applied to reduce the sample complexity. However, we found that protein abundance and other physicochemical properties, such as molecular weight (Mw), grand average of hydropathicity (GRAVY), aliphatic index, and isoelectric point (pI) have no notable correlation with digestion priority of proteins.

Pepsin immobilized in dextran-modified fused-silica capillaries for on-line protein digestion and peptide mapping

Energy Technology Data Exchange (ETDEWEB)

Stigter, E.C.A. [Division of Biomedical Analysis, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands)], E-mail: e.c.a.stigter@uu.nl; Jong, G.J. de; Bennekom, W.P. van [Division of Biomedical Analysis, Department of Pharmaceutical Sciences, Faculty of Science, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands)

2008-07-07

On-line digestion of proteins under acidic conditions was studied using micro-reactors consisting of dextran-modified fused-silica capillaries with covalently immobilized pepsin. The proteins used in this study differed in molecular weight, isoelectric point and sample composition. The injected protein samples were completely digested in 3 min and the digest was analyzed with micro-high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The different proteins present in the samples could be identified with a Mascot database search on the basis of auto-MS/MS data. It proved also to be possible to digest and analyze protein mixtures with a sequence coverage of 55% and 97% for the haemoglobin {beta}- and {alpha}-chain, respectively, and 35-55% for the various casein variants. Protease auto-digestion, sample carry-over and loss of signal due to adsorption of the injected proteins were not observed. The backpressure of the reactor is low which makes coupling to systems such as Surface Plasmon Resonance biosensors, which do not tolerate too high pressure, possible. The reactor was stable for at least 40 days when used continuously.

Pepsin immobilized in dextran-modified fused-silica capillaries for on-line protein digestion and peptide mapping.

Science.gov (United States)

Stigter, E C A; de Jong, G J; van Bennekom, W P

2008-07-07

On-line digestion of proteins under acidic conditions was studied using micro-reactors consisting of dextran-modified fused-silica capillaries with covalently immobilized pepsin. The proteins used in this study differed in molecular weight, isoelectric point and sample composition. The injected protein samples were completely digested in 3 min and the digest was analyzed with micro-high performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). The different proteins present in the samples could be identified with a Mascot database search on the basis of auto-MS/MS data. It proved also to be possible to digest and analyze protein mixtures with a sequence coverage of 55% and 97% for the haemoglobin beta- and alpha-chain, respectively, and 35-55% for the various casein variants. Protease auto-digestion, sample carry-over and loss of signal due to adsorption of the injected proteins were not observed. The backpressure of the reactor is low which makes coupling to systems such as Surface Plasmon Resonance biosensors, which do not tolerate too high pressure, possible. The reactor was stable for at least 40 days when used continuously.

Thesis Abstract Bean (Phaseolus vulgaris L.) lines: chemical composition and protein digestibility.

Science.gov (United States)

Mesquita, F R; Silva, M I A; Corrêa, A D

2016-05-09

The bean represents the main source of proteins for the low income populations, although the digestibility of those proteins is relatively low. Consequently, the programs of plant genetic breeding have been working on the search for new lines with higher protein levels. Thus, with the purpose of supplying information to the researchers, in this study, 21 bean (Phaseolus vulgaris L.) lines were analyzed for the centesimal and mineral composition, protein digestibility, phenolic compounds, and trypsin inhibitor. The entirely randomized experimental design was used with 21 treatments (lines) and three repetitions. All values were within the following ranges: 22.34 to 36.28 g crude protein/100 g dry matter (DM); 7.56 to 20.91 g neutral detergent fiber/100 g DM; 0.53 to 2.55 g fat/100 g DM and 2.97 to 4.87 g ashes/100 g DM. The levels of phosphorus, potassium, calcium, magnesium, and sulfur, in g/100 g DM, varied from 0.45 to 0.72; 1.51 to 2.48; 0.03 to 0.28; 0.18 to 0.34 and 0.28 to 0.45, respectively. Regarding copper, manganese, zinc and iron, the levels, in mg/kg DM, varied from 11.37 to 17.73; 14.93 to 28.90; 36.67 to 69.90 and 71.37 to 126.90, respectively. The in vitro protein digestibility varied from 18.03 to 48.32%. The levels of phenolic compounds varied from 0.28 to 1.08 mg acid tanic/100 g DM and the one of trypsin inhibitor from 59.93 to 151.07 trypsin inhibited units/mg DM. Among the lines with higher protein contents, "ESAL 569" (beige with brown stripe) presented the largest protein digestibility and considerable levels of minerals. "P-180" (beige with brown stripe) was one of the lines with higher crude protein contents and digestibilities, and also presented high levels for most of the minerals. No relation between protein digestibility and the contents of phenolic compounds or trypsin inhibitor was observed.

Malting process optimization for protein digestibility enhancement in finger millet grain.

Science.gov (United States)

Hejazi, Sara Najdi; Orsat, Valérie

2016-04-01

Finger millet (Eleusine coracana) is a nutritious, gluten-free, and drought resistant cereal containing high amounts of protein, carbohydrate, and minerals. However, bio-availability of these nutrients is restricted due to the presence of an excessive level of anti-nutrient components, mainly phytic acid, tannin, and oxalate. It has been shown that a well-designed malting/germination process can significantly reduce these anti-nutrients and consequently enhance the nutrient availability. In the present study, the effects of two important germination factors, duration and temperature, on the enhancement of in-vitro protein digestibility of finger millet were thoroughly investigated and optimized. Based on a central composite design, the grains were germinated for 24, 36, and 48 h at 22, 26, and 30 °C. For all factor combinations, protein, peptide, phytic acid, tannin, and oxalate contents were evaluated and digestibility was assessed. It was shown that during the malting/germinating process, both temperature and duration factors significantly influenced the investigated quantities. Germination of finger millet for 48 h at 30 °C increased protein digestibility from 74 % (for native grain) up to 91 %. Besides, it notably decreased phytic acid, tannin, and oxalate contents by 45 %, 46 %, and 29 %, respectively. Linear correlations between protein digestibility and these anti-nutrients were observed.

Effect of extrusion conditions on the physico-chemical properties and in vitro protein digestibility of canola meal.

Science.gov (United States)

Zhang, Bo; Liu, Guo; Ying, Danyang; Sanguansri, Luz; Augustin, Mary Ann

2017-10-01

Canola meal has potential as a high protein food ingredient. The extrusion-induced changes in color, pH, extractable protein and in vitro protein digestibility of canola meal under different extrusion conditions was assessed. The extrusion barrel moisture (24%, 30% or 36%) and screw kneading block length (0, 30 or 60mm) were used as independent process parameters. Extrusion at high barrel moisture (36%) favored protein aggregation resulting in lower extractable protein compared to extrusion at the lowest barrel moisture (24%). At lower barrel moisture contents (24% and 30%), a longer kneading block length increased extractable protein but this was not the case at 36% barrel moisture. Canola protein digestibility was improved upon extrusion at 30% barrel moisture but there was no significant change at lower (24%) or higher (36%) barrel moisture. The kneading block length of the screw had no significant effect on the canola protein digestibility within the same barrel moisture level. The relationship between the physico-chemical parameters and in vitro digestibility was examined. This study highlighted the complex interplay of extrusion processing variables that affect protein degradation and the interaction of components, with consequent effects on protein digestibility. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tracking the fate of pasta (T. Durum semolina) immunogenic proteins by in vitro simulated digestion.

Science.gov (United States)

Mamone, Gianfranco; Nitride, Chiara; Picariello, Gianluca; Addeo, Francesco; Ferranti, Pasquale; Mackie, Alan

2015-03-18

The aim of the present study was to identify and characterize the celiacogenic/immunogenic proteins and peptides released during digestion of pasta (Triticum durum semolina). Cooked pasta was digested using a harmonized in vitro static model of oral-gastro-duodenal digestion. The course of pasta protein digestion was monitored by SDS-PAGE, and gluten proteins were specifically analyzed by Western blot using sera of celiac patients. Among the allergens, nonspecific lipid-transfer protein was highly resistant to gastro-duodenal hydrolysis, while other digestion-stable allergens such as α-amylase/trypsin inhibitors were not detected being totally released in the pasta cooking water. To simulate the final stage of intestinal degradation, the gastro-duodenal digesta were incubated with porcine jejunal brush-border membrane hydrolases. Sixty-one peptides surviving the brush-border membrane peptidases were identified by liquid chromatography-mass spectrometry, including several gluten-derived sequences encrypting different motifs responsible for the induction of celiac disease. These results provide new insights into the persistence of wheat-derived peptides during digestion of cooked pasta samples.

Effect of endogenous proteins and lipids on starch digestibility in rice flour.

Science.gov (United States)

Ye, Jiangping; Hu, Xiuting; Luo, Shunjing; McClements, David Julian; Liang, Lu; Liu, Chengmei

2018-04-01

The composition and structure of the food matrix can have a major impact on the digestion. The aim of this work was to investigate the effects of endogenous proteins and lipids on starch digestibility in rice flour, with an emphasis on establishing the underlying physicochemical mechanisms involved. Native long-grain indica rice flour and rice flour with the lipids and/or proteins removed were subjected to a simulated digestion in vitro. A significant increase in starch digestibility was observed after removal of proteins, lipids, or both. The starch digestibility of the rice flour without lipids was slightly lower than that without proteins, even though the proteins content was about 10-fold higher than the lipids content. Microstructural analysis suggested that the proteins and lipids were normally attached to the surfaces of the starch granules in the native rice flour, thus inhibiting their contact with digestive enzymes. Moreover, the proteins and lipids restricted the swelling of the starch granules, which may have decreased their digestion by reducing their surface areas. In addition, amylose-lipid complex was detected in the rice flour, which is also known to slow down starch digestion. These results have important implications for the design of foods with improved nutritional profiles. Copyright © 2018 Elsevier Ltd. All rights reserved.

EFFECT OF MALTING ON PROTEIN DIGESTIBILITY OF SOME ...

African Journals Online (AJOL)

Protein digestibility of sorghum is generally low. Malting is one of the processing methods which can be applied to improve this digestibility. It is a method whose technology is well known by local communities in Kenya. The objective of this study was to investigate the effect of malting on the digestibility of some varieties of ...

Kinetic Stability of Proteins in Beans and Peas: Implications for Protein Digestibility, Seed Germination, and Plant Adaptation.

Science.gov (United States)

Xia, Ke; Pittelli, Sandy; Church, Jennifer; Colón, Wilfredo

2016-10-12

Kinetically stable proteins (KSPs) are resistant to the denaturing detergent sodium dodecyl sulfate (SDS). Such resilience makes KSPs resistant to proteolytic degradation and may have arisen in nature as a mechanism for organismal adaptation and survival against harsh conditions. Legumes are well-known for possessing degradation-resistant proteins that often diminish their nutritional value. Here we applied diagonal two-dimensional (D2D) SDS-polyacrylamide gel electrophoresis (PAGE), a method that allows for the proteomics-level identification of KSPs, to a group of 12 legumes (mostly beans and peas) of agricultural and nutritional importance. Our proteomics results show beans that are more difficult to digest, such as soybean, lima beans, and various common beans, have high contents of KSPs. In contrast, mung bean, red lentil, and various peas that are highly digestible contain low amounts of KSPs. Identified proteins with high kinetic stability are associated with warm-season beans, which germinate at higher temperatures. In contrast, peas and red lentil, which are cool-season legumes, contain low levels of KSPs. Thus, our results show protein kinetic stability is an important factor in the digestibility of legume proteins and may relate to nutrition efficiency, timing of seed germination, and legume resistance to biotic stressors. Furthermore, we show D2D SDS-PAGE is a powerful method that could be applied for determining the abundance and identity of KSPs in engineered and wild legumes and for advancing basic research and associated applications.

Relationship between Molecular Structure Characteristics of Feed Proteins and Protein In vitro Digestibility and Solubility.

Science.gov (United States)

Bai, Mingmei; Qin, Guixin; Sun, Zewei; Long, Guohui

2016-08-01

The nutritional value of feed proteins and their utilization by livestock are related not only to the chemical composition but also to the structure of feed proteins, but few studies thus far have investigated the relationship between the structure of feed proteins and their solubility as well as digestibility in monogastric animals. To address this question we analyzed soybean meal, fish meal, corn distiller's dried grains with solubles, corn gluten meal, and feather meal by Fourier transform infrared (FTIR) spectroscopy to determine the protein molecular spectral band characteristics for amides I and II as well as α-helices and β-sheets and their ratios. Protein solubility and in vitro digestibility were measured with the Kjeldahl method using 0.2% KOH solution and the pepsin-pancreatin two-step enzymatic method, respectively. We found that all measured spectral band intensities (height and area) of feed proteins were correlated with their the in vitro digestibility and solubility (p≤0.003); moreover, the relatively quantitative amounts of α-helices, random coils, and α-helix to β-sheet ratio in protein secondary structures were positively correlated with protein in vitro digestibility and solubility (p≤0.004). On the other hand, the percentage of β-sheet structures was negatively correlated with protein in vitro digestibility (pdigestibility at 28 h and solubility. Furthermore, the α-helix-to-β-sheet ratio can be used to predict the nutritional value of feed proteins.

Rapid microscale in-gel processing and digestion of proteins using surface acoustic waves.

Science.gov (United States)

Kulkarni, Ketav P; Ramarathinam, Sri H; Friend, James; Yeo, Leslie; Purcell, Anthony W; Perlmutter, Patrick

2010-06-21

A new method for in-gel sample processing and tryptic digestion of proteins is described. Sample preparation, rehydration, in situ digestion and peptide extraction from gel slices are dramatically accelerated by treating the gel slice with surface acoustic waves (SAWs). Only 30 minutes total workflow time is required for this new method to produce base peak chromatograms (BPCs) of similar coverage and intensity to those observed for traditional processing and overnight digestion. Simple set up, good reproducibility, excellent peptide recoveries, rapid turnover of samples and high confidence protein identifications put this technology at the fore-front of the next generation of proteomics sample processing tools.

Digestion of crude protein and organic matter of leaves by rumen microbes in vitro

Energy Technology Data Exchange (ETDEWEB)

Ciszuk, A.; Murphy, M.

1982-01-01

22 leaf specimens, of which 6 were from an energy-woods project, were studied by incubation in vitro with rumen microbes or pepsin-hydrochloric acid. Several were also examined in situ using the nylon-bag technique. Many leaves, despite their low fiber and high crude protein content, gave low values for organic matter digestibility. The crude protein degradation by rumen microbes or pepsin-hydrochloric acid was low, on average, compared with hay. There was a wide variation among leaf specimens. Variation was also found as regards ammonia production in short-term (4 hours) incubation. No close correlation was found between crude protein content and crude protein degradation, or between the estimates of ruminal degradation and of pepsin-hydrochloric acid digestibility. This suggest that there are leaves that gives ruminants substantial amounts of digestible protein yet escape ruminal fermentation. (Refs. 12).

Processed Meat Protein and Heat-Stable Peptide Marker Identification Using Microwave-Assisted Tryptic Digestion

Directory of Open Access Journals (Sweden)

Magdalena Montowska

2016-01-01

Full Text Available New approaches to rapid examination of proteins and peptides in complex food matrices are of great interest to the community of food scientists. The aim of the study is to examine the influence of microwave irradiation on the acceleration of enzymatic cleavage and enzymatic digestion of denatured proteins in cooked meat of five species (cattle, horse, pig, chicken and turkey and processed meat products (coarsely minced, smoked, cooked and semi-dried sausages. Severe protein aggregation occurred not only in heated meat under harsh treatment at 190 °C but also in processed meat products. All the protein aggregates were thoroughly hydrolyzed aft er 1 h of trypsin treatment with short exposure times of 40 and 20 s to microwave irradiation at 138 and 303 W. There were much more missed cleavage sites observed in all microwave-assisted digestions. Despite the incompleteness of microwave-assisted digestion, six unique peptide markers were detected, which allowed unambiguous identification of processed meat derived from the examined species. Although the microwave-assisted tryptic digestion can serve as a tool for rapid and high-throughput protein identification, great caution and pre-evaluation of individual samples is recommended in protein quantitation.

[Evaluation of the adjusted amino acid score by digestibility for estimating the protein quality and protein available in food and diets].

Science.gov (United States)

Pak, N; Vera, G; Araya, H

1985-03-01

The purpose of the present study was to evaluate the amino acid score adjusted by digestibility to estimate protein quality and utilizable protein in foods and diets, considering net protein utilization (NPU) as a biological reference method. Ten foods of vegetable origin and ten of animal origin, as well as eight mixtures of foods of vegetable and animal origin were studied. When all the foods were considered, a positive (r = 0.83) and highly significant correlation (p less than 0.001) between NPU and the amino acid score adjusted by digestibility was found. When the foods were separated according to their origin, this correlation was positive only for the foods of vegetable origin (r = 0.93) and statistically significant (p less than 0.001). Also, only in those foods were similar values found between NPU and amino acid score adjusted by digestibility, as well as in utilizable protein estimated considering both methods. Caution is required to interpret protein quality and utilizable protein values of foods of animal origin and mixtures of foods of vegetable and animal origin when the amino acid score method adjusted by digestibility, or NPU, are utilized.

Rapid and Efficient Protein Digestion using Trypsin Coated Magnetic Nanoparticles under Pressure Cycles

Energy Technology Data Exchange (ETDEWEB)

Lee, Byoungsoo; Lopez-Ferrer, Daniel; Kim, Byoung Chan; Na, Hyon Bin; Park, Yong Il; Weitz, Karl K.; Warner, Marvin G.; Hyeon, Taeghwan; Lee, Sang-Won; Smith, Richard D.; Kim, Jungbae

2011-01-01

Trypsin-coated magnetic nanoparticles (EC-TR/NPs), prepared via a simple crosslinking of the enzyme to magnetic nanoparticles, were highly stable and could be easily captured using a magnet after the digestion was complete. EC-TR/NPs showed a negligible loss of trypsin activity after multiple uses and continuous shaking, while a control sample of covalently-attached trypsin on NPs resulted in a rapid inactivation under the same conditions due to the denaturation and autolysis of trypsin. Digestions were carried out on a single model protein, a five protein mixture, and a whole mouse brain proteome, and also compared for digestion at atmospheric pressure and 37 ºC for 12 h, and in combination with pressure cycling technology (PCT) at room temperature for 1 min. In all cases, the EC-TR/NPs performed equally as well or better than free trypsin in terms of the number of peptide/protein identifications and reproducibility across technical replicates. However, the concomitant use of EC-TR/NPs and PCT resulted in very fast (~1 min) and more reproducible digestions.

High throughput techniques to reveal the molecular physiology and evolution of digestion in spiders.

Science.gov (United States)

Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Verhaert, Peter D E M; Lopes, Adriana R

2016-09-07

Spiders are known for their predatory efficiency and for their high capacity of digesting relatively large prey. They do this by combining both extracorporeal and intracellular digestion. Whereas many high throughput ("-omics") techniques focus on biomolecules in spider venom, so far this approach has not yet been applied to investigate the protein composition of spider midgut diverticula (MD) and digestive fluid (DF). We here report on our investigations of both MD and DF of the spider Nephilingis (Nephilengys) cruentata through the use of next generation sequencing and shotgun proteomics. This shows that the DF is composed of a variety of hydrolases including peptidases, carbohydrases, lipases and nuclease, as well as of toxins and regulatory proteins. We detect 25 astacins in the DF. Phylogenetic analysis of the corresponding transcript(s) in Arachnida suggests that astacins have acquired an unprecedented role for extracorporeal digestion in Araneae, with different orthologs used by each family. The results of a comparative study of spiders in distinct physiological conditions allow us to propose some digestion mechanisms in this interesting animal taxon. All the high throughput data allowed the demonstration that DF is a secretion originating from the MD. We identified enzymes involved in the extracellular and intracellular phases of digestion. Besides that, data analyses show a large gene duplication event in Araneae digestive process evolution, mainly of astacin genes. We were also able to identify proteins expressed and translated in the digestive system, which until now had been exclusively associated to venom glands.

Influence of heat and shear induced protein aggregation on the in vitro digestion rate of whey proteins.

Science.gov (United States)

Singh, Tanoj K; Øiseth, Sofia K; Lundin, Leif; Day, Li

2014-11-01

Protein intake is essential for growth and repair of body cells, the normal functioning of muscles, and health related immune functions. Most food proteins are consumed after undergoing various degrees of processing. Changes in protein structure and assembly as a result of processing impact the digestibility of proteins. Research in understanding to what extent the protein structure impacts the rate of proteolysis under human physiological conditions has gained considerable interest. In this work, four whey protein gels were prepared using heat processing at two different pH values, 6.8 and 4.6, with and without applied shear. The gels showed different protein network microstructures due to heat induced unfolding (at pH 6.8) or lack of unfolding, thus resulting in fine stranded protein networks. When shear was applied during heating, particulate protein networks were formed. The differences in the gel microstructures resulted in considerable differences in their rheological properties. An in vitro gastric and intestinal model was used to investigate the resulting effects of these different gel structures on whey protein digestion. In addition, the rate of digestion was monitored by taking samples at various time points throughout the in vitro digestion process. The peptides in the digesta were profiled using SDS-polyacrylamide gel electrophoresis, reversed-phase-HPLC and LC-MS. Under simulated gastric conditions, whey proteins in structured gels were hydrolysed faster than native proteins in solution. The rate of peptides released during in vitro digestion differed depending on the structure of the gels and extent of protein aggregation. The outcomes of this work highlighted that changes in the network structure of the protein can influence the rate and pattern of its proteolysis under gastrointestinal conditions. Such knowledge could assist the food industry in designing novel food formulations to control the digestion kinetics and the release of biologically

Digestion proteomics: tracking lactoferrin truncation and peptide release during simulated gastric digestion.

Science.gov (United States)

Grosvenor, Anita J; Haigh, Brendan J; Dyer, Jolon M

2014-11-01

The extent to which nutritional and functional benefit is derived from proteins in food is related to its breakdown and digestion in the body after consumption. Further, detailed information about food protein truncation during digestion is critical to understanding and optimising the availability of bioactives, in controlling and limiting allergen release, and in minimising or monitoring the effects of processing and food preparation. However, tracking the complex array of products formed during the digestion of proteins is not easily accomplished using classical proteomics. We here present and develop a novel proteomic approach using isobaric labelling to mapping and tracking protein truncation and peptide release during simulated gastric digestion, using bovine lactoferrin as a model food protein. The relative abundance of related peptides was tracked throughout a digestion time course, and the effect of pasteurisation on peptide release assessed. The new approach to food digestion proteomics developed here therefore appears to be highly suitable not only for tracking the truncation and relative abundance of released peptides during gastric digestion, but also for determining the effects of protein modification on digestibility and potential bioavailability.

Convergent evolution of plant and animal embryo defences by hyperstable non-digestible storage proteins.

Science.gov (United States)

Pasquevich, María Yanina; Dreon, Marcos Sebastián; Qiu, Jian-Wen; Mu, Huawei; Heras, Horacio

2017-11-20

Plants have evolved sophisticated embryo defences by kinetically-stable non-digestible storage proteins that lower the nutritional value of seeds, a strategy that have not been reported in animals. To further understand antinutritive defences in animals, we analysed PmPV1, massively accumulated in the eggs of the gastropod Pomacea maculata, focusing on how its structure and structural stability features affected its capacity to withstand passage through predator guts. The native protein withstands >50 min boiling and resists the denaturing detergent sodium dodecyl sulphate (SDS), indicating an unusually high structural stability (i.e., kinetic stability). PmPV1 is highly resistant to in vitro proteinase digestion and displays structural stability between pH 2.0-12.0 and 25-85 °C. Furthermore, PmPV1 withstands in vitro and mice digestion and is recovered unchanged in faeces, supporting an antinutritive defensive function. Subunit sequence similarities suggest a common origin and tolerance to mutations. This is the first known animal genus that, like plant seeds, lowers the nutritional value of eggs by kinetically-stable non-digestible storage proteins that survive the gut of predators unaffected. The selective pressure of the harsh gastrointestinal environment would have favoured their appearance, extending by convergent evolution the presence of plant-like hyperstable antinutritive proteins to unattended reproductive stages in animals.

Cooking temperature is a key determinant of in vitro meat protein digestion rate: investigation of underlying mechanisms.

Science.gov (United States)

Bax, Marie-Laure; Aubry, Laurent; Ferreira, Claude; Daudin, Jean-Dominique; Gatellier, Philippe; Rémond, Didier; Santé-Lhoutellier, Véronique

2012-03-14

The present study aimed to evaluate the digestion rate and nutritional quality of pig muscle proteins in relation to different meat processes (aging, mincing, and cooking). Under our experimental conditions, aging and mincing had little impact on protein digestion. Heat treatments had different temperature-dependent effects on the meat protein digestion rate and degradation potential. At 70 °C, the proteins underwent denaturation that enhanced the speed of pepsin digestion by increasing enzyme accessibility to protein cleavage sites. Above 100 °C, oxidation-related protein aggregation slowed pepsin digestion but improved meat protein overall digestibility. The digestion parameters defined here open new insights on the dynamics governing the in vitro digestion of meat protein. However, the effect of cooking temperature on protein digestion observed in vitro needs to be confirmed in vivo.

Effects of sources of protein and enzyme supplementation on protein digestibility and chyme characteristics in broilers.

Science.gov (United States)

Yu, B; Lee, T T T; Chiou, P W S

2002-07-01

1. The purpose of this study was to evaluate the effects of protein source and enzyme supplementation on protein digestibility and chyme characteristics in broilers. 2. One hundred and twenty growing (13 d old) and 60 finishing (34 d old) Arbor Acre strain commercial male broilers were selected and placed into individual metabolic cages. 3. The experiment was a 5 x 2 factorial arrangement with 5 different sources of protein: casein, fish meal, soybean meal (SBM), soy protein concentrate (SPC), maize gluten meal (MGM) and two levels of protease (bromelain), 0 and 65 CDU/kg diets. 4. The diets were iso-nitrogenous and semi-purified, with Cr2O3 as an indicator for determination of ileal digestibility and chyme characteristics. 5. Apparent ileal protein digestibility (AIPD) in both growing and finishing chickens was highest on the casein diet, followed by fish meal, SBM, SPC and MGM. 6. Enzyme inclusion did not improve protein digestibility, but significantly decreased the digesta pH value in the gizzard and increased pH in the ileum in the 3-week-old broilers. 7. The digesta pH values in the gizzard and duodenum were significantly lower in the SBM and fish meal groups compared with the other protein groups. The molecular weight distribution pattern of the soluble protein in the chyme of the gastrointestinal (GI) segments showed a similar trend, regardless of the enzyme inclusion or the stage of growth. 8. The molecular weight profile of soluble protein changed dynamically in the casein fed broilers from the gizzard to ileum and the low molecular weight proteins, < 7 kDa, reached maximum levels at the ileum. The molecular weight profile of the soluble protein in the SBM and SPC changed between the jejunum and the ileum and in the intermediate molecular soluble protein weight (7 to 10 kDa) was significantly decreased. This indicated that the hydrolysis process began from the middle to the posterior end of the small intestine. 9. Similar profiles were also shown with

Values for digestible indispensable amino acid scores (DIAAS) for some dairy and plant proteins may better describe protein quality than values calculated using the concept for protein digestibility-corrected amino acid scores (PDCAAS).

Science.gov (United States)

Mathai, John K; Liu, Yanhong; Stein, Hans H

2017-02-01

An experiment was conducted to compare values for digestible indispensable amino acid scores (DIAAS) for four animal proteins and four plant proteins with values calculated as recommended for protein digestibility-corrected amino acid scores (PDCAAS), but determined in pigs instead of in rats. Values for standardised total tract digestibility (STTD) of crude protein (CP) and standardised ileal digestibility (SID) of amino acids (AA) were calculated for whey protein isolate (WPI), whey protein concentrate (WPC), milk protein concentrate (MPC), skimmed milk powder (SMP), pea protein concentrate (PPC), soya protein isolate (SPI), soya flour and whole-grain wheat. The PDCAAS-like values were calculated using the STTD of CP to estimate AA digestibility and values for DIAAS were calculated from values for SID of AA. Results indicated that values for SID of most indispensable AA in WPI, WPC and MPC were greater (P<0·05) than for SMP, PPC, SPI, soya flour and wheat. With the exception of arginine and tryptophan, the SID of all indispensable AA in SPI was greater (P<0·05) than in soya flour, and with the exception of threonine, the SID of all indispensable AA in wheat was less (P<0·05) than in all other ingredients. If the same scoring pattern for children between 6 and 36 months was used to calculate PDCAAS-like values and DIAAS, PDCAAS-like values were greater (P<0·05) than DIAAS values for SMP, PPC, SPI, soya flour and wheat indicating that PDCAAS-like values estimated in pigs may overestimate the quality of these proteins.

Improvement of Protein Digestibility in Jatropha curcas Seed Cakes by Gamma Irradiation

International Nuclear Information System (INIS)

Sudprasert, Wanwisa; Pakkong, Pannee; Thiengtham, Jamroen; Chandang, Pipatpong

2011-06-01

Full text: The effect of gamma radiation on protein digestibility of Jatropha curcas press cake was investigated using in vitro digestibility technique. Six varieties of Jatropha curcas seeds were subjected to cobalt-60 gamma radiation at doses of 10-100 kGy. All treated seeds were defatted by screw press. In vitro protein digest abilities in defatted seeds were assayed using trinitrobenzene sulphonic acid (TNBS) method, by which the contents of alpha amino induced from the function of enzymes were determined using L-alanine as a reference standard. It was found that irradiation treatment at 60 kGy significantly increased the protein digestibility by 15-92%. Also, the results showed that moisture, crude protein, fat and ash contents were unchanged by irradiation, whereas fiber was significantly decreased (p < 0.05). Therefore, irradiation could serve as a possible processing method for protein utilization improvement in defatted Jatropha curcas seeds before using as a protein supplement in animal feed

Protein identification and in vitro digestion of fractions from Tenebrio molitor

NARCIS (Netherlands)

Yi, Liya; Boekel, van M.A.J.S.; Boeren, Sjef; Lakemond, Catriona M.M.

2016-01-01

The nutritional value of insect protein is evaluated not only in amino acid composition, but also in protein digestibility. The general amino acid composition of Tenebrio molitor has been reported before, but limited knowledge is available on its digestibility. The objective of this study was to

Stability of milk fat globule membrane proteins toward human enzymatic gastrointestinal digestion.

Science.gov (United States)

Le, T T; Van de Wiele, T; Do, T N H; Debyser, G; Struijs, K; Devreese, B; Dewettinck, K; Van Camp, J

2012-05-01

The milk fat globule membrane (MFGM) fraction refers to the thin film of polar lipids and membrane proteins that surrounds fat globules in milk. It is its unique biochemical composition that renders MFGM with some beneficial biological activities, such as anti-adhesive effects toward pathogens. However, a prerequisite for the putative bioactivity of MFGM is its stability during gastrointestinal digestion. We, therefore, subjected MFGM material, isolated from raw milk, to an in vitro enzymatic gastrointestinal digestion. Sodium dodecyl sulfate PAGE, in combination with 2 staining methods, Coomassie Blue and periodic acid Schiff staining, was used to evaluate polypeptide patterns of the digest, whereas mass spectrometry was used to confirm the presence of specific MFGM proteins. Generally, it was observed that glycoproteins showed higher resistance to endogenous proteases compared with non-glycosylated proteins. Mucin 1 displayed the highest resistance to digestion and a considerable part of this protein was still detected at its original molecular weight after gastric and small intestine digestion. Cluster of differentiation 36 was also quite resistant to pepsin. A significant part of periodic acid Schiff 6/7 survived the gastric digestion, provided that the lipid moiety was not removed from the MFGM material. Overall, MFGM glycoproteins are generally more resistant to gastrointestinal digestion than serum milk proteins and the presence of lipids, besides glycosylation, may protect MFGM glycoproteins from gastrointestinal digestion. This gastrointestinal stability makes MFGM glycoproteins amenable to further studies in which their putative health-promoting effects can be explored. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Ruminal degradation and intestinal digestibility of protein and amino acids in high-protein feedstuffs commonly used in dairy diets.

Science.gov (United States)

Paz, H A; Klopfenstein, T J; Hostetler, D; Fernando, S C; Castillo-Lopez, E; Kononoff, P J

2014-10-01

A study was conducted to determine the rumen degradation and intestinal digestibility of crude protein (CP) and AA, and AA composition of the rumen-undegradable protein (RUP) from 3 sources of blood meal (BM1, BM2, and BM3), canola meal (CM), low-fat distillers dried grains with solubles (LFDG), soybean meal (SBM), and expeller soybean meal (ESBM). Two Holstein cows fitted with ruminal and proximal duodenal cannulas were used for in situ incubation of 16h and for the mobile bag technique. To correct for bacterial contamination of the RUP, 2 methods were used: purines and DNA as bacterial markers. Ruminal degradations of CP were 85.3, 29.8, 40.7, 75.7, 76.9, 68.8, and 37.0 ± 3.93% for BM1, BM2, BM3, CM, LFDG, SBM, and ESBM, respectively. Ruminal degradation of both total essential AA and nonessential AA followed a similar pattern to that of CP across feedstuffs. Based on the ratio of AA concentration in the RUP to AA concentration in the original feedstuff, ruminal incubation decreased (ratio 1) the concentrations of Ile and Met across feedstuffs. Compared with purines, the use of DNA as bacterial marker resulted in a higher estimate of bacterial CP contamination for CM and lower estimates for LFDG and ESBM. Intestinal digestibility of RUP could not be estimated for BM1, BM3, and SBM due to insufficient recovery of residue. For the remaining feedstuffs, intestinal digestibility of RUP was highest for ESBM, followed by BM2 and LFDG, and lowest for CM: 98.8, 87.9, 89.7, and 72.4 ± 1.40%, respectively. Intestinal absorbable dietary protein was higher for BM2 compared with CM and LFDG, at 61.7, 17.9, and 20.7 ± 2.73% CP, respectively. As prices fluctuate, intestinal absorbable protein or AA may be used as a tool to aid in the selection among feedstuffs with different protein quality. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Functional properties and in vitro trypsin digestibility of red kidney bean (Phaseolus vulgaris L.) protein isolate: Effect of high-pressure treatment.

Science.gov (United States)

Yin, Shou-Wei; Tang, Chuan-He; Wen, Qi-Biao; Yang, Xiao-Quan; Li, Lin

2008-10-15

The effects of high-pressure (HP) treatment at 200-600MPa, prior to freeze-drying, on some functional properties and in vitro trypsin digestibility of vicilin-rich red kidney bean (Phaseolus vulgaris L.) protein isolate (KPI) were investigated. Surface hydrophobicity and free sulfhydryl (SH) and disulfide bond (SS) contents were also evaluated. HP treatment resulted in gradual unfolding of protein structure, as evidenced by gradual increases in fluorescence strength and SS formation from SH groups, and decrease in denaturation enthalpy change. The protein solubility of KPI was significantly improved at pressures of 400MPa or higher, possibly due to formation of soluble aggregate from insoluble precipitate. HP treatment at 200 and 400MPa significantly increased emulsifying activity index (EAI) and emulsion stability index (ESI); however, EAI was significantly decreased at 600MPa (relative to untreated KPI). The thermal stability of the vicilin component was not affected by HP treatment. Additionally, in vitro trypsin digestibility of KPI was decreased only at a pressure above 200MPa and for long incubation time (e.g., 120min). The data suggest that some physiochemical and functional properties of vicilin-rich kidney proteins can be improved by means of high-pressure treatment. Copyright © 2008 Elsevier Ltd. All rights reserved.

INVITRO DIGESTIBILITY OF PROTEIN FROM BARLEY AND OTHER CEREALS

DEFF Research Database (Denmark)

Buchmann, N. B.

1979-01-01

An in vitro method for measuring barley protein digestibility is presented. Samples were first incubated with pepsin in HCl; pancreatin was then added concomitantly with a bacteriostatic borate buffer. After TCA-precipitation, soluble nitrogen was measured. The digestion was unaffected...... by accumulated free amino acids. There were no free amino acids following pepsin treatment, but the essential ones were well liberated by pancreatin. Results for barley grown in the field or in pots, and for decortified barley fractions agreed with true digestibility values determined with rats. Of these samples...... digestibility depended on the type of enzyme and on the enzyme-to-substrate ratio....

White clover fractions as protein source for monogastrics - Dry matter digestibility and Protein Digestibility-Corrected Amino Acid Scores

DEFF Research Database (Denmark)

Stødkilde, Lene; Damborg, Vinni K; Jørgensen, Henry

2018-01-01

BACKGROUND: The aim was to evaluate white clover as an alternative protein source for monogastrics. White clover plant and leaves were processed using a screw-press resulting in a solid pulp and a juice from which protein was acid-precipitated. The chemical composition of all fractions...... was determined and digestibility of dry matter (DM) and protein was assessed in an experiment with growing rats. RESULTS: Protein concentrates were produced with crude protein (CP) content of 451 g/kg DM and 530 g/kg DM for white clover plant and leaves, respectively and a pulp with CP content of 313 and 374 g...

Digestion of cooked meat proteins is slightly affected by age as assessed using the dynamic gastrointestinal TIM model and mass spectrometry.

Science.gov (United States)

Denis, S; Sayd, T; Georges, A; Chambon, C; Chalancon, S; Santé-Lhoutellier, V; Blanquet-Diot, S

2016-06-15

In humans, meat ensures the supply of proteins with high nutritional value and indispensable amino acids. The main goal of the present study was to compare the degradation of meat proteins in adult and elderly digestive conditions. Cooked meat was subjected to in vitro digestion in the dynamic multi-compartmental TIM (TNO gastroIntestinal Model) system. Digestibility and bioaccessibility were determined using nitrogen balance and digestion products were identified using mass spectrometry. The TIM model was adapted according to in vivo data to mimic the specific digestive conditions of elderly people. Meat protein digestibility and bioaccessibility were around 96 and 60% respectively and were not influenced by age (P > 0.05). As much as 800 peptides were identified in the duodenal and jejunal compartments issued from 50 meat proteins with a percentage of coverage varying from 13 to 69%. Six proteins, mainly from the cytosol, were differentially hydrolyzed under the adult and elderly digestive conditions. Pyruvate kinase was the only protein clearly showing a delay in its degradation under elderly digestive conditions. This study provides significant insights into the understanding of meat protein dynamic digestion. Such data will be helpful to design in vivo studies aiming to evaluate dietary strategies that can attenuate muscle mass loss and more generally maintain a better quality of life in the elderly population.

Effect of Bacillus subtilis and Bacillus licheniformis supplementation in diets with low- and high-protein content on ileal crude protein and amino acid digestibility and intestinal microbiota composition of growing pigs.

Science.gov (United States)

Kaewtapee, Chanwit; Burbach, Katharina; Tomforde, Georgina; Hartinger, Thomas; Camarinha-Silva, Amélia; Heinritz, Sonja; Seifert, Jana; Wiltafsky, Markus; Mosenthin, Rainer; Rosenfelder-Kuon, Pia

2017-01-01

Bacillus spp. seem to be an alternative to antimicrobial growth promoters for improving animals' health and performance. However, there is little information on the effect of Bacillus spp. in combination with different dietary crude protein (CP) levels on the ileal digestibility and microbiota composition. Therefore, the objective of this study was to determine the effect of Bacillus spp. supplementation to low- (LP) and high-protein diets (HP) on ileal CP and amino acid (AA) digestibility and intestinal microbiota composition. Eight ileally cannulated pigs with an initial body weight of 28.5 kg were randomly allocated to a row-column design with 8 pigs and 3 periods of 16 d each. The assay diets were based on wheat-barley-soybean meal with two protein levels: LP (14% CP, as-fed) and HP diet (18% CP, as-fed). The LP and HP diets were supplemented with or without Bacillus spp. at a level of 0.04% (as-fed). The apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP and AA was determined. Bacterial community composition from ileal digesta was analyzed by Illumina amplicon sequencing and quantitative real-time PCR. Data were analyzed as a 2 × 2 factorial design using the GLIMMIX procedures of SAS. The supplementation with Bacillus spp. did not affect both AID and SID of CP and AA in growing pigs. Moreover, there was no difference in AID of CP and AA between HP and LP diets, but SID of cystine, glutamic acid, glycine, and proline was lower ( P  digestibility, whereas LP diet may reduce the flow of undigested protein to the large intestine of pigs.

Growth of Nile tilapia post-larvae from broodstock fed diet with different levels of digestible protein and digestible energy

Directory of Open Access Journals (Sweden)

Silia Maria de Negreiros Sousa

2013-08-01

Full Text Available This study was carried out to evaluate the influence of different levels of digestible energy and digestible protein in diets of Nile tilapia (Oreochromis niloticus broodstock on offspring growth during sex reversal stage. A total of 2,700 post-larvae (8.2±0.001 mg derived from breeders fed nine diets with distinct levels of digestible protein (28, 34 and 40% DP and digestible energy (2,800; 3,400; and 4,000 kcal DE.kg-1 were stored in twenty-seven 70 L tanks. After 30 days of growth, their average final weight (AFW, g, average weight gain (AWG, g, final standard length (SL, cm, condition factor (CF, specific growth rate (SGR, %/day, stock uniformity (UNI, %, survival (SUR, % and sex reversal rate (SRR, % were measured. Although female nutrition is thought to influence the performance or quality of progeny during early life stages, no influence of diets supplied to broodstock was detected on any parameter. Nonetheless, the offspring presented commercially satisfactory growth rates. Thus, diets containing 28% of digestible protein and 2,800 kcal of digestible energy.kg of diet-1 can be used to feed Nile tilapia broodstock without jeopardizing offspring performance during the sex reversal phase.

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

Science.gov (United States)

Vilcacundo, R; Barrio, D; Carpio, C; García-Ruiz, A; Rúales, J; Hernández-Ledesma, B; Carrillo, W

2017-09-01

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%).

Effect of Different Heat Treatments on In Vitro Digestion of Egg White Proteins and Identification of Bioactive Peptides in Digested Products.

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Wang, Xuefen; Qiu, Ning; Liu, Yaping

2018-04-01

Chicken eggs are ingested by people after a series of processes, but to date, only a few studies have explored the nutrient variations caused by different heat treatments. In this work, the impacts of different heat treatments (4, 56, 65, and 100 °C on the in vitro digestibility of egg white proteins were investigated by hydrolysis with pepsin or pepsin + pancreatin to simulate human gastrointestinal digestion, and the digested products were identified using Nano-LC-ESI-MS/MS. Egg white proteins treated at 65 °C had the highest in vitro pepsin digestibility value whereas the pepsin + pancreatin digestibility increased significantly (P cooking temperature was raised. The molecular weight distribution of the digested products indicated that, when compared to pepsin-treated samples, pepsin + pancreatin-treated samples contained more low-molecular-weight peptides (m/z egg white digested products, especially in samples treated at 4 and 100 °C. These findings may facilitate a better understanding of nutritive values of egg white proteins and their digested products under different cooking temperatures, such as antibacterial and antioxidant peptides identified in the digestion samples treated, respectively at 4 and 100 °C. This study also provided information for improving the applications of eggs in the food industry as well as a theoretical basis for egg consumption. © 2018 Institute of Food Technologists®.

Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

Energy Technology Data Exchange (ETDEWEB)

Fischnaller, Martin; Köck, Rainer; Bakry, Rania, E-mail: rania.bakry@uibk.ac.at; Bonn, Günther K.

2014-05-01

Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling.

Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

International Nuclear Information System (INIS)

Fischnaller, Martin; Köck, Rainer; Bakry, Rania; Bonn, Günther K.

2014-01-01

Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling

Gross and true ileal digestible amino acid contents of several animal body proteins and their hydrolysates.

Science.gov (United States)

Cui, J; Chong, B; Rutherfurd, S M; Wilkinson, B; Singh, H; Moughan, P J

2013-07-01

Amino acid compositions of ovine muscle, ovine myofibrillar protein, ovine spleen, ovine liver, bovine blood plasma, bovine blood globulins and bovine serum albumin and the amino acid compositions and in vivo (laboratory rat) true ileal amino acid digestibilities of hydrolysates (sequential hydrolysis with Neutrase, Alcalase and Flavourzyme) of these protein sources were determined. True ileal amino acid digestibility differed (Pprotein hydrolysates. The ovine myofibrillar protein and liver hydrolysates were the most digestible, with a mean true ileal digestibility across all amino acids of 99%. The least digestible protein hydrolysate was bovine serum albumin with a comparable mean true ileal digestibility of 93%. When the digestible amino acid contents were expressed as proportions relative to lysine, considerable differences, across the diverse protein sources, were found in the pattern of predicted absorbed amino acids. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of mercury on lysosomal protein digestion in the kidney proximal tubule

International Nuclear Information System (INIS)

Madsen, K.M.; Christensen, E.I.

1978-01-01

The effect of mercury on renal lysosomal protein digestion was studied after administration of mercury in vitro and in vivo. Mercuric chloride or methylmercury chloride was added in vitro to lysosomal enzymes isolated from normal rats, and subsequently, digestion experiments were carried out using 125 I-labeled lysozyme or cytochrome c as substrate proteins. Both mercury compounds produced a concentration-dependent inhibition of the degradation of the proteins, mercuric chloride being the strongest inhibitor. Mercuric chloride was also administered to rats in vivo for 5 to 8 months. Renal lysosomal enzymes from these animals also had a decreased ability to digest the two substrate proteins. Furthermore, the digestion of lysozyme intravenously injected into mercury-intoxicated rats was decreased in renal cortical slices incubated in vitro. Electron microscope autoradiography showed that intravenously injected labeled lysozyme was located primarily over lysosomes in proximal tubule cells 1 hour after injection in both control animals and mercury-intoxicated rats. These results suggest a decreased catabolism of low molecular weight proteins in the kidney during chronic mercury intoxication

Direct digestion of proteins in living cells into peptides for proteomic analysis.

Science.gov (United States)

Chen, Qi; Yan, Guoquan; Gao, Mingxia; Zhang, Xiangmin

2015-01-01

To analyze the proteome of an extremely low number of cells or even a single cell, we established a new method of digesting whole cells into mass-spectrometry-identifiable peptides in a single step within 2 h. Our sampling method greatly simplified the processes of cell lysis, protein extraction, protein purification, and overnight digestion, without compromising efficiency. We used our method to digest hundred-scale cells. As far as we know, there is no report of proteome analysis starting directly with as few as 100 cells. We identified an average of 109 proteins from 100 cells, and with three replicates, the number of proteins rose to 204. Good reproducibility was achieved, showing stability and reliability of the method. Gene Ontology analysis revealed that proteins in different cellular compartments were well represented.

Robust Trypsin Coating on Electrospun Polymer Nanofibers in Rigorous Conditions and Its Uses for Protein Digestion

Energy Technology Data Exchange (ETDEWEB)

Ahn, Hye-Kyung; Kim, Byoung Chan; Jun, Seung-Hyun; Chang, Mun Seock; Lopez-Ferrer, Daniel; Smith, Richard D.; Gu, Man Bock; Lee, Sang-Won; Kim, Beom S.; Kim, Jungbae

2010-12-15

An efficient protein digestion in proteomic analysis requires the stabilization of proteases such as trypsin. In the present work, trypsin was stabilized in the form of enzyme coating on electrospun polymer nanofibers (EC-TR), which crosslinks additional trypsin molecules onto covalently-attached trypsin (CA-TR). EC-TR showed better stability than CA-TR in rigorous conditions, such as at high temperatures of 40 °C and 50 °C, in the presence of organic co-solvents, and at various pH's. For example, the half-lives of CA-TR and EC-TR were 0.24 and 163.20 hours at 40 ºC, respectively. The improved stability of EC-TR can be explained by covalent-linkages on the surface of trypsin molecules, which effectively inhibits the denaturation, autolysis, and leaching of trypsin. The protein digestion was performed at 40 °C by using both CA-TR and EC-TR in digesting a model protein, enolase. EC-TR showed better performance and stability than CA-TR by maintaining good performance of enolase digestion under recycled uses for a period of one week. In the same condition, CA-TR showed poor performance from the beginning, and could not be used for digestion at all after a few usages. The enzyme coating approach is anticipated to be successfully employed not only for protein digestion in proteomic analysis, but also for various other fields where the poor enzyme stability presently hampers the practical applications of enzymes.

Effect of pre-treatment on in vitro gastric digestion of quinoa protein (Chenopodium quinoa Willd.) obtained by wet and dry fractionation.

Science.gov (United States)

Opazo-Navarrete, M; Schutyser, M A I; Boom, R M; Janssen, A E M

2018-02-01

Quinoa protein was isolated from quinoa seeds using wet fractionation that resulted in a protein isolate (QPI) with a high protein purity of 87.1% (w/dw) and a protein yield of around 54%, and a dry fractionation method delivered a quinoa protein concentrate (QPC) with a purity of 27.8% (w/dw) and yield of around 47%. The dry fractionation process only involves milling and sieving and keeps the protein in its natural, native state. The aim was to study the in vitro gastric digestibility of both protein. Attention was paid to thermal pre-treatment of QPI and QPC. QPC showed significantly higher (p < .05) digestibility than QPI samples. The results were interpreted with a simple double exponential model. The fraction of easily digested protein in QPC is higher than for QPI. The better digestibility of the QPC was explained by the prevention of the formation of large aggregates during pre-heating of the protein.

Effect of the presence of protein on lipolysis and lipid oxidation occurring during in vitro digestion of highly unsaturated oils.

Science.gov (United States)

Nieva-Echevarría, Bárbara; Goicoechea, Encarnación; Guillén, María D

2017-11-15

The effect of the presence of ovalbumin and soy protein isolate on lipolysis and oxidation taking place during in vitro gastrointestinal digestion of slightly oxidized sunflower and flaxseed oils was addressed. The extent of lipolysis, the molar proportions of acyl groups/fatty acids after digestion, and the oxidation products formed were studied by Proton Nuclear Magnetic Resonance. The presence of proteins provoked a higher hydrolysis in triglycerides, a lower decrease of polyunsaturated chains, and a lower generation of oxidation compounds (conjugated dienes in chains having also hydroperoxy/hydroxy groups, epoxides and aldehydes); the formation of hydroxides was clearly favoured over that of hydroperoxides. Study of headspace composition by Solid Phase Microextraction-Gas Chromatography/Mass Spectrometry confirmed that oxidation advanced to a lesser extent in the presence of protein. Thus, amino acids/peptides released during digestion may show antioxidant properties, affecting not only the extent of lipid oxidation, but also reactions pathways. Copyright © 2017 Elsevier Ltd. All rights reserved.

Levels of digestible protein to surubim (Pseudoplatystoma sp. reared in net cages

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Claucia Aparecida Honorato

2014-10-01

Full Text Available The Pseudoplatystoma sp. is species of carnivorous fish that require special attention in the diet offered. This work had the objective to determine the digestible protein requirement of juvenile the Pseudoplatystoma sp. reared in net cages. The test consisted of four isoenergetic diets (2606.69 ± 39.16 kcal kg-1 of digestible energy containing increasing levels of digestible protein (23, 24, 26 and 28%PD provided to juveniles of surubim (157.35±11.23g for five months. The parameters of growth, fillet composition, metabolic liver enzymes and morphometry of the intestine and liver were analyzed in completely randomized design with four treatments and four replicates. An increase of protein in the diet provided better weight gain. The metabolic liver enzymes increased in fish fed 24PD. The histopathological changes were not observed in the liver of the fish. The bowel histology showed adaptation to increased protein in the diet until the 26 level PD. juveniles of Pseudoplatystoma sp. Were demanding in digestible protein, showing the best results of production performance and nutrient use efficiency with the diet containing 28%PD.

Gut luminal endogenous protein: implications for the determination of ileal amino acid digestibility in humans.

Science.gov (United States)

Moughan, Paul J; Rutherfurd, Shane M

2012-08-01

The true ileal digestibility assay provides the most informative measure of digestibility to assess bioavailability of amino acids in foods for humans. To determine 'true' estimates of ileal amino acid digestibility, requires that endogenous amino acids present in digesta at the terminal ileum be quantified. The amounts of endogenous amino acids in ileal digesta can be determined after feeding an animal or human a protein-free diet (traditional approach) or by various methods after giving a protein-containing diet. When the protein-free method has been applied with adult human subjects an overall mean value (three separate studies) for endogenous ileal nitrogen flow of 800 mg N/d has been reported. This value is considerably lower than a comparable value obtained after feeding protein of 1852 mg N/d (mean of four separate studies), and thus endogenous ileal N and amino acids should be measured under conditions of protein alimentation. There is some confusion concerning the terminology used to define digestibility, with the term "true" digestibility having different adopted meanings. Here, true amino acid digestibility is defined as apparent amino acid digestibility corrected for the basal amino acid losses determined after giving either a protein-free or a protein-containing diet. Basal losses should be determined at a defined dry-matter and protein intake. The protein-free diet approach to determining endogenous amino acids is considered unphysiological and basal losses refer to ileal endogenous amino acid flows associated with digesta dry-matter flow, and not including "specific" effects of dietary factors such as non starch polysaccharides and anti nutritional factors. Arguments are advanced that the enzyme hydrolysed protein/ultra filtration method may be suitable for routine application with a cannulated pig model, to obtain physiologically-valid basal estimates of ileal endogenous amino acids to allow calculation of true ileal amino acid digestibility in the

Pepsin Digested Oat Bran Proteins: Separation, Antioxidant Activity, and Identification of New Peptides

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Ariane Vanvi

2016-01-01

Full Text Available The aim of this study was to determine pepsin hydrolysis conditions to produce digested oat bran proteins with higher radical scavenging activities and separate and identify peptides. Isolated proteins were then digested with different concentrations of pepsin and incubation times. Hydrolysates produced with 1 : 30 enzyme substrate (E/S ratio and 2 h possessed the highest peroxyl radical scavenging activity, 608 ± 17 µM TE/g (compared to 456–474 µM TE/g for other digests, and was therefore subsequently fractionated into eight fractions (F1–F8 by high performance liquid chromatography (HPLC. F1 and F2 had little activity because of their low protein contents. Activities of F3–F8 were 447–874 µM TE/g, 20–36%, and 10–14% in the peroxyl, superoxide anion, and hydroxyl radical tests, respectively. Liquid chromatography-tandem mass spectrometry (LC-MS/MS was used to identify a total of fifty peptides that may have contributed to the activity of F3, a fraction that better scavenged radicals.

Efficient Anaerobic Digestion of Microalgae Biomass: Proteins as a Key Macromolecule.

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Magdalena, Jose Antonio; Ballesteros, Mercedes; González-Fernandez, Cristina

2018-05-06

Biogas generation is the least complex technology to transform microalgae biomass into bioenergy. Since hydrolysis has been pointed out as the rate limiting stage of anaerobic digestion, the main challenge for an efficient biogas production is the optimization of cell wall disruption/hydrolysis. Among all tested pretreatments, enzymatic treatments were demonstrated not only very effective in disruption/hydrolysis but they also revealed the impact of microalgae macromolecular composition in the anaerobic process. Although carbohydrates have been traditionally recognized as the polymers responsible for the low microalgae digestibility, protease addition resulted in the highest organic matter solubilization and the highest methane production. However, protein solubilization during the pretreatment can result in anaerobic digestion inhibition due to the release of large amounts of ammonium nitrogen. The possible solutions to overcome these negative effects include the reduction of protein biomass levels by culturing the microalgae in low nitrogen media and the use of ammonia tolerant anaerobic inocula. Overall, this review is intended to evidence the relevance of microalgae proteins in different stages of anaerobic digestion, namely hydrolysis and methanogenesis.

Digestibility of animal and vegetable protein ingredients by pirarucu juveniles, Arapaima gigas

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Filipe dos Santos Cipriano

Full Text Available ABSTRACT The objective of this study was to determine the apparent digestibility coefficients of energy, protein, and amino acids in protein ingredients by pirarucu juveniles. A test was conducted with six protein ingredients: meat and bone meal, fish meal, hydrolyzed feather meal, poultry by-product meal, soybean meal, and corn gluten meal. Three repetitions were used for each tested ingredient. A reference feed was used with 430 g kg−1 crude protein and 19.63 kJ g−1 gross energy. The test feeds consisted of the replacement of 30% of the reference feeds with the test ingredients. Chromium oxide was added to the feeds at 1 g kg−1 as an external marker. Eighteen juveniles with an average weight of 235±36 g were used. The best apparent digestibility coefficients of protein were found for fish meal, followed by the poultry by-product meal and meat and bone meal. However, except for gluten, all the tested ingredients presented protein digestibilities above 0.70. The crude energy apparent digestibility coefficient was higher for animal ingredients, above 0.75, than for vegetable ingredients, which presented values below 0.60. Pirarucu efficiently uses the protein from the tested ingredients, regardless of origin. However, it has a preferential ability to use the energy from animal ingredients.

Lipo-Protein Emulsion Structure in the Diet Affects Protein Digestion Kinetics, Intestinal Mucosa Parameters and Microbiota Composition.

Science.gov (United States)

Oberli, Marion; Douard, Véronique; Beaumont, Martin; Jaoui, Daphné; Devime, Fabienne; Laurent, Sandy; Chaumontet, Catherine; Mat, Damien; Le Feunteun, Steven; Michon, Camille; Davila, Anne-Marie; Fromentin, Gilles; Tomé, Daniel; Souchon, Isabelle; Leclerc, Marion; Gaudichon, Claire; Blachier, François

2018-01-01

Food structure is a key factor controlling digestion and nutrient absorption. We test the hypothesis that protein emulsion structure in the diet may affect digestive and absorptive processes. Rats (n = 40) are fed for 3 weeks with two diets chemically identical but based on lipid-protein liquid-fine (LFE) or gelled-coarse (GCE) emulsions that differ at the macro- and microstructure levels. After an overnight fasting, they ingest a 15 N-labeled LFE or GCE test meal and are euthanized 0, 15 min, 1 h, and 5 h later. 15 N enrichment in intestinal contents and blood are measured. Gastric emptying, protein digestion kinetics, 15 N absorption, and incorporation in blood protein and urea are faster with LFE than GCE. At 15 min time point, LFE group shows higher increase in GIP portal levels than GCE. Three weeks of dietary adaptation leads to higher expression of cationic amino acid transporters in ileum of LFE compared to GCE. LFE diet raises cecal butyrate and isovalerate proportion relative to GCE, suggesting increased protein fermentation. LFE diet increases fecal Parabacteroides relative abundance but decreases Bifidobacterium, Sutterella, Parasutterella genera, and Clostridium cluster XIV abundance. Protein emulsion structure regulates digestion kinetics and gastrointestinal physiology, and could be targeted to improve food health value. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Decreasing the amount of trypsin in in-gel digestion leads to diminished chemical noise and improved protein identifications.

Science.gov (United States)

Hu, Mo; Liu, Yanhua; Yu, Kaiwen; Liu, Xiaoyun

2014-09-23

Pre-fractionation by gel electrophoresis is often combined with liquid chromatography-mass spectrometry (LC-MS) for large-scale profiling of complex protein samples. An essential component of this widely applied proteomic platform is in-gel protein digestion. In nearly two decades of practicing this approach, an extremely high level of trypsin has been utilized due to the consideration of slow enzyme diffusion into the gel matrix. Here we report that trypsin autolysis products contribute to the bulk of chemical noise in in-gel digestion and remarkably we found evidence that the amount of trypsin can be slashed by an order of magnitude with comparable digestion performance. By revising perhaps the most critical element of this decade-old digestion protocol, the proteomics community relying on gel separation prior to LC-MS analysis will benefit instantly from much lowered cost due to enzyme expenditure. More importantly, substantially reduced chemical noise (i.e., trypsin self-cleavage products) as a result of less enzyme usage translates into more protein identifications when limited amounts of samples are the interest of interrogation. In-gel digestion is one of the most widely used methods in proteomics. An exceedingly high level of trypsin has been utilized due to the consideration of slow enzyme diffusion into the gel matrix. This requirement has been faithfully kept in nearly two decades of practicing this approach. Here we report that trypsin concentration can be slashed by at least an order of magnitude while still providing comparable digestion performance. Thus the proteomics community relying on gel separation prior to LC-MS analysis will benefit instantly from much lowered enzyme cost. More importantly, substantially reduced chemical noise (i.e., trypsin autolysis products) due to less enzyme usage translates into ~30% more protein identifications when limited amounts of protein samples are analyzed. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of intestinal brush border peptidases in the simulated digestion of milk proteins.

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Picariello, Gianluca; Miralles, Beatriz; Mamone, Gianfranco; Sánchez-Rivera, Laura; Recio, Isidra; Addeo, Francesco; Ferranti, Pasquale

2015-05-01

This study aimed to assess the impact of the "often neglected" intestinal brush border membranes (BBMs) hydrolases on dietary peptides, exploring the possibility that the disintegration of proteins progressed in the small intestine up to a "core" of intrinsically stable oligopeptides, persisting independently on the up-stream breakdown. Samples of sodium caseinate, skim milk powder, and whey protein isolate were submitted to in vitro simulated gastropancreatic digestion using two different procedures: (i) a simplified model involving the main compartmental specific proteases; (ii) a static digestion method based on a frameset of parameters inferred from in vivo. The gastroduodenal digesta were further hydrolyzed with peptidases from porcine jejunal BBM. The peptidomes arising from the two digestion models, characterized by combined HPLC and MS techniques, differed to some extent. However, only specific protein domains survived digestion, among which are potential bioactive or immunogenic (food allergy) peptides. The degree of hydrolysis (DH) after BBM digestion (70-77%) practically did not differ between the digestion models and significantly increased the DH after duodenal steps. Any in vitro digestion model should be supplemented with a jejunal phase to realistically determine the bioaccessibility and bioavailability of dietary peptides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New stable isotope method to measure protein digestibility and response to pancreatic enzyme intake in cystic fibrosis.

Science.gov (United States)

Engelen, M P K J; Com, G; Anderson, P J; Deutz, N E P

2014-12-01

Adequate protein intake and digestion are necessary to prevent muscle wasting in cystic fibrosis (CF). Accurate and easy-to-use methodology to quantify protein maldigestion is lacking in CF. To measure protein digestibility and the response to pancreatic enzyme intake in CF by using a new stable isotope methodology. In 19 CF and 8 healthy subjects, protein digestibility was quantified during continuous (sip) feeding for 6 h by adding (15)N-labeled spirulina protein and L-[ring-(2)H5]phenylalanine (PHE) to the nutrition and measuring plasma ratio [(15)N]PHE to [(2)H5]PHE. Pancreatic enzymes were ingested after 2 h in CF and the response in protein digestibility was assessed. To exclude difference in mucosal function, postabsorptive whole-body citrulline (CIT) production rate was measured by L-[5-(13)C-5,5-(2)H2]-CIT pulse and blood samples were taken to analyze tracer-tracee ratios. Protein digestibility was severely reduced in the CF group (47% of healthy subjects; P digestibility in CF until 90% of values obtained by healthy subjects. Maximal digestibility was reached at 100 min and maintained for 80 min. Stratification into CF children (n = 10) and adults showed comparable values for protein digestibility and similar kinetic responses to pancreatic enzyme intake. Whole-body citrulline production was elevated in CF indicating preserved mucosal function. Protein digestibility is severely compromised in patients with CF as measured by this novel and easy-to-use stable isotope approach. Pancreatic enzymes are able to normalize protein digestibility in CF, albeit with a severe delay. Registration ClinicalTrials.gov = NCT01494909. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Digestion and microbial protein synthesis in sheep as affected by ...

African Journals Online (AJOL)

Useni , Alain

enzyme (EFE) on the in vitro gas production (GP) and ANKOM digestion systems on the mixture of milled ... determine the EFE effect on the DM, CP and NDF digestion of a mixture of lucerne hay and wheat straw .... and the microbial protein synthesis (MPS) measured as purine derivates (RNA equivalent in µg/DM g) on.

In vitro digestibility of individual amino acids in rumen-undegraded protein: the modified three-step procedure and the immobilized digestive enzyme assay.

Science.gov (United States)

Boucher, S E; Calsamiglia, S; Parsons, C M; Stern, M D; Moreno, M Ruiz; Vázquez-Añón, M; Schwab, C G

2009-08-01

Three soybean meal, 3 SoyPlus (West Central Cooperative, Ralston, IA), 5 distillers dried grains with solubles, and 5 fish meal samples were used to evaluate the modified 3-step in vitro procedure (TSP) and the in vitro immobilized digestive enzyme assay (IDEA; Novus International Inc., St. Louis, MO) for estimating digestibility of AA in rumen-undegraded protein (RUP-AA). In a previous experiment, each sample was ruminally incubated in situ for 16 h, and in vivo digestibility of AA in the intact samples and in the rumen-undegraded residues (RUR) was obtained for all samples using the precision-fed cecectomized rooster assay. For the modified TSP, 5 g of RUR was weighed into polyester bags, which were then heat-sealed and placed into Daisy(II) incubator bottles. Samples were incubated in a pepsin/HCl solution followed by incubation in a pancreatin solution. After this incubation, residues remaining in the bags were analyzed for AA, and digestibility of RUP-AA was calculated based on disappearance from the bags. In vitro RUP-AA digestibility estimates obtained with this procedure were highly correlated to in vivo estimates. Corresponding intact feeds were also analyzed via the pepsin/pancreatin steps of the modified TSP. In vitro estimates of AA digestibility of the feeds were highly correlated to in vivo RUP-AA digestibility, which suggests that the feeds may not need to be ruminally incubated before determining RUP-AA digestibility in vitro. The RUR were also analyzed via the IDEA kits. The IDEA values of the RUR were good predictors of RUP-AA digestibility in soybean meal, SoyPlus, and distillers dried grains with solubles, but the IDEA values were not as good predictors of RUP-AA digestibility in fish meal. However, the IDEA values of intact feed samples were also determined and were highly correlated to in vivo RUP-AA digestibility for all feed types, suggesting that the IDEA value of intact feeds may be a better predictor of RUP-AA digestibility than the IDEA

Proteolytic Digestion and TiO2 Phosphopeptide Enrichment Microreactor for Fast MS Identification of Proteins

Science.gov (United States)

Deng, Jingren; Lazar, Iulia M.

2016-04-01

The characterization of phosphorylation state(s) of a protein is best accomplished by using isolated or enriched phosphoprotein samples or their corresponding phosphopeptides. The process is typically time-consuming as, often, a combination of analytical approaches must be used. To facilitate throughput in the study of phosphoproteins, a microreactor that enables a novel strategy for performing fast proteolytic digestion and selective phosphopeptide enrichment was developed. The microreactor was fabricated using 100 μm i.d. fused-silica capillaries packed with 1-2 mm beds of C18 and/or TiO2 particles. Proteolytic digestion-only, phosphopeptide enrichment-only, and sequential proteolytic digestion/phosphopeptide enrichment microreactors were developed and tested with standard protein mixtures. The protein samples were adsorbed on the C18 particles, quickly digested with a proteolytic enzyme infused over the adsorbed proteins, and further eluted onto the TiO2 microreactor for enrichment in phosphopeptides. A number of parameters were optimized to speed up the digestion and enrichments processes, including microreactor dimensions, sample concentrations, digestion time, flow rates, buffer compositions, and pH. The effective time for the steps of proteolytic digestion and enrichment was less than 5 min. For simple samples, such as standard protein mixtures, this approach provided equivalent or better results than conventional bench-top methods, in terms of both enzymatic digestion and selectivity. Analysis times and reagent costs were reduced ~10- to 15-fold. Preliminary analysis of cell extracts and recombinant proteins indicated the feasibility of integration of these microreactors in more advanced workflows amenable for handling real-world biological samples.

Dry anaerobic digestion of lignocellulosic and protein residues

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Maryam M Kabir

2015-12-01

Full Text Available Utilisation of wheat straw and wool textile waste in dry anaerobic digestion (AD process was investigated. Dry-AD of the individual substrates as well as co-digestion of those were evaluated using different total solid (TS contents ranging between 6 to 30%. Additionally, the effects of the addition of nutrients and cellulose- or protein-degrading enzymes on the performance of the AD process were also investigated. Dry-AD of the wheat straw resulted in methane yields of 0.081 – 0.200 Nm3CH4/kgVS with the lowest and highest values obtained at 30 and 21% TS, respectively. The addition of the cellulolytic enzymes could significantly increase the yield in the reactor containing 13% TS (0.231 Nm3CH4/kg VS. Likewise, degradation of wool textile waste was enhanced significantly at TS of 13% with the addition of the protein-degrading enzyme (0.131 Nm3CH4/kg VS. Furthermore, the co-digestion of these two substrates showed higher methane yields compared with the methane potentials calculated for the individual fractions at all the investigated TS contents due to synergetic effects and better nutritional balance.

Cooking Chicken Breast Reduces Dialyzable Iron Resulting from Digestion of Muscle Proteins

Directory of Open Access Journals (Sweden)

Aditya S. Gokhale

2014-01-01

Full Text Available The purpose of this research was to study the effect of cooking chicken breast on the production of dialyzable iron (an in vitro indicator of bioavailable iron from added ferric iron. Chicken breast muscle was cooked by boiling, baking, sautéing, or deep-frying. Cooked samples were mixed with ferric iron and either extracted with acid or digested with pepsin and pancreatin. Total and ferrous dialyzable iron was measured after extraction or digestion and compared to raw chicken samples. For uncooked samples, dialyzable iron was significantly enhanced after both extraction and digestion. All cooking methods led to markedly reduced levels of dialyzable iron both by extraction and digestion. In most cooked, digested samples dialyzable iron was no greater than the iron-only (no sample control. Cooked samples showed lower levels of histidine and sulfhydryls but protein digestibility was not reduced, except for the sautéed sample. The results showed that, after cooking, little if any dialyzable iron results from digestion of muscle proteins. Our research indicates that, in cooked chicken, residual acid-extractable components are the most important source of dialyzable iron.

Cooking Chicken Breast Reduces Dialyzable Iron Resulting from Digestion of Muscle Proteins.

Science.gov (United States)

Gokhale, Aditya S; Mahoney, Raymond R

2014-01-01

The purpose of this research was to study the effect of cooking chicken breast on the production of dialyzable iron (an in vitro indicator of bioavailable iron) from added ferric iron. Chicken breast muscle was cooked by boiling, baking, sautéing, or deep-frying. Cooked samples were mixed with ferric iron and either extracted with acid or digested with pepsin and pancreatin. Total and ferrous dialyzable iron was measured after extraction or digestion and compared to raw chicken samples. For uncooked samples, dialyzable iron was significantly enhanced after both extraction and digestion. All cooking methods led to markedly reduced levels of dialyzable iron both by extraction and digestion. In most cooked, digested samples dialyzable iron was no greater than the iron-only (no sample) control. Cooked samples showed lower levels of histidine and sulfhydryls but protein digestibility was not reduced, except for the sautéed sample. The results showed that, after cooking, little if any dialyzable iron results from digestion of muscle proteins. Our research indicates that, in cooked chicken, residual acid-extractable components are the most important source of dialyzable iron.

Anti-nutritional factors and digestibility of protein in Cayocar brasiliense seeds

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Virgínia Campos SILVESTRINI

2017-10-01

Full Text Available Abstract The Brazilian Cerrado presents a wide variety of natural products, including the Pequi (Caryocar brasiliense. The important factor that determines the dietary and nutritional ideality of protein is degestitibility. This work aims to evaluate the protein digestibility of Pequi seeds and the presence of anti-nutritional factors. The protein Pequi almonds were extracted, toasted and untoasted. Evaluation digestibility was structurally characterized by SDS-PAGE 15%, which can be used to analyze simulated gastric fluid (SFG and digestion in intestinal fluid (SFI in the presence of pepsin and trypsin/chymotrypsin. The extract from Pequi almonds showed inhibitory activity and was not detected hemagglutination. The intensity of the bands according to 2S albumins, after heat treatment, did not decrease in comparison to the condition native, significantly. In the crisp crude extract, which was incubated under SGF and SIF, the intensity of the corresponding bands at 8 and 3 kDa was resistant to SGF and indigestible after 4 hours under SIF. The characterization of Pequi almonds demonstrated that the product of the crude extract has anti-nutritional factors, which were confirmed by evaluating digestibility.

Fecal collection methods for the determination of protein digestibility in bullfrogs

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Marta Verardino De Stéfani

2015-08-01

Full Text Available Adequate methods for the determination of protein digestibility in bullfrogs are important for the understanding of nutrient utilization. Therefore, this study evaluated two methods of feces collection: intestinal dissection and fecal decantation, using cylindric-conical tanks. Frogs were fed with a commercial diet (45% crude protein which was ground and supplemented with 0.5% chromium oxide III. The frogs were fasted 48h before force-feeding (5% of the animal's live weight. For the decantation method, the animals were sacrificed 36 h after force-feeding and feces were collected directly from the large intestine. For the sedimentation method, feces were collected when they appeared in the tubes attached to the front end of the cylindric tanks. No significant difference (P>0.05 in the apparent digestibility coefficients of crude protein for dietary was observed between the methods tested (74.0% and 76.4% for the dissection and decantation methods, respectively. In conclusion, both methods can be used for the determination of protein digestibility of bullfrog feeds

Thermostable trypsin conjugates immobilized to biogenic magnetite show a high operational stability and remarkable reusability for protein digestion

Science.gov (United States)

Pečová, M.; Šebela, M.; Marková, Z.; Poláková, K.; Čuda, J.; Šafářová, K.; Zbořil, R.

2013-03-01

In this work, magnetosomes produced by microorganisms were chosen as a suitable magnetic carrier for covalent immobilization of thermostable trypsin conjugates with an expected applicability for efficient and rapid digestion of proteins at elevated temperatures. First, a biogenic magnetite was isolated from Magnetospirillum gryphiswaldense and its free surface was coated with the natural polysaccharide chitosan containing free amino and hydroxy groups. Prior to covalent immobilization, bovine trypsin was modified by conjugating with α-, β- and γ-cyclodextrin. Modified trypsin was bound to the magnetic carriers via amino groups using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide as coupling reagents. The magnetic biomaterial was characterized by magnetometric analysis and electron microscopy. With regard to their biochemical properties, the immobilized trypsin conjugates showed an increased resistance to elevated temperatures, eliminated autolysis, had an unchanged pH optimum and a significant storage stability and reusability. Considering these parameters, the presented enzymatic system exhibits properties that are superior to those of trypsin forms obtained by other frequently used approaches. The proteolytic performance was demonstrated during in-solution digestion of model proteins (horseradish peroxidase, bovine serum albumin and hen egg white lysozyme) followed by mass spectrometry. It is shown that both magnetic immobilization and chemical modification enhance the characteristics of trypsin making it a promising tool for protein digestion.

Analysis of Protein Amino Acids in Tobacco Using Microwave Digestion of Plant Material

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Moldoveanu SC

2014-12-01

Full Text Available This paper describes a technique using microwave digestion and gas chromatography-mass spectrometry (GC-MS, which makes possible the analysis of protein amino acids in tobacco. The technique involves first the measurement of free amino acids, a hydrolysis using microwave digestion, and a measurement of total resulting amino acids. The content of protein amino acids is determined from the difference of total and free amino acids. The digestion is performed with aqueous 6 N HCl (with 1% phenol for two hours in a microwave at 120°C in sealed vials. The GC-MS analysis is performed after the amino acids are derivatized with N-methyl-N-(t-butyldimethylsilyltrifluoroacetamide (MTBSTFA. The technique provides reliable results with less than 10% relative standard deviation (RSD for most amino acids. Only the determination of very low level amino acids is affected by larger errors. The method provides results for free amino acids that are in very good agreement with those obtained by high performance liquid chromatography (HPLC, and also results for protein levels in tobacco in agreement with data previously reported in the literature. Results are given for several single grade tobaccos and for tobacco blends from four Kentucky reference cigarettes.

An attempt to predict protein digestibility of feedstuffs in pigs by using the values for poultry

NARCIS (Netherlands)

Roosenstein, A.M.; Cone, J.W.; Beynen, A.C.

2000-01-01

The protein value of feedstuffs for pigs depends on the ileal digestibility of amino acids. The measurement of ileal digestibility requires cannulated pigs, which is time consuming and causes discomfort in the animals. We have tested the hypothesis that faecal digestibility of crude protein and

Accelerated protein digestion and amino acid absorption after Roux-en-Y gastric bypass

DEFF Research Database (Denmark)

Bojsen-Møller, Anna Kirstine; Jacobsen, Siv H; Dirksen, Carsten

2015-01-01

BACKGROUND: Roux-en-Y gastric bypass (RYGB) involves exclusion of major parts of the stomach and changes in admixture of gastro-pancreatic enzymes, which could have a major impact on protein digestion and amino acid absorption. OBJECTIVE: We investigated the effect of RYGB on amino acid appearance......: RYGB accelerates caseinate digestion and amino acid absorption, resulting in faster and higher but more transient postprandial elevation of plasma amino acids. Changes are likely mediated by accelerated intestinal nutrient entry and clearly demonstrate that protein digestion is not impaired after RYGB...

The impact of tannins on protein, dry matter, and energy digestion in moose (Alces alces)

Science.gov (United States)

Donald E. Spalinger; W.B. Collins; Thomas A. Hanley; N.E. Cassara; A.M. Carnahan

2010-01-01

Recent work suggests that moose (Alces alces [L., 1758]) in the boreal ecoregion may be nutritionally limited by the availability of protein as a consequence of both low nitrogen (N) concentrations and high tannin levels in their principal foods. However, the ability of moose to digest protein in the presence of tannins is unknown. We undertook a...

Lipo-protein emulsion structure in the diet affects protein digestion kinetics, intestinal mucosa parameters and microbiota composition

OpenAIRE

Oberli, Marion; Douard, Véronique; Beaumont, Martin; Jaoui, Daphné; Devime, Fabienne; Laurent, Sandy; Chaumontet, Catherine; Mat, Damien; Le Feunteun, Steven; Michon, Camille; Davila, Anne-Marie; Fromentin, Gilles; Tomé, Daniel; Souchon, Isabelle; Leclerc, Marion

2017-01-01

SCOPE: Food structure is a key factor controlling digestion and nutrient absorption. We tested the hypothesis that protein emulsion structure in the diet may affect digestive and absorptive processes. METHODS & RESULTS: Rats (n = 40) were fed for 3 weeks two diets chemically identical but based on lipid-protein liquid-fine (LFE) or gelled-coarse (GCE) emulsions that differ at the macro- and micro-structure levels. After an overnight fasting, they ingested a 15 N-labeled LFE or GCE te...

Effects of N,N-dimethylglycine sodium salt on apparent digestibility, vitamin E absorption, and serum proteins in broiler chickens fed a high- or low-fat diet.

Science.gov (United States)

Prola, L; Nery, J; Lauwaerts, A; Bianchi, C; Sterpone, L; De Marco, M; Pozzo, L; Schiavone, A

2013-05-01

The objective of this study was to assess the effect of supplementation with sodium salt of N,N-dimethylglycine (DMG-Na) on apparent digestibility (AD) in broiler chickens fed low- and high-fat diets. Twenty-eight 1-d-old broiler chickens were fed one of the dietary treatments: a low-fat diet (LF) or a high-fat diet (HF) supplemented with or without 1,000 mg/kg of DMG-Na. Body weight and feed consumption were recorded at 14 and 35 d of age. Average daily growth, daily feed intake, and feed conversion ratio were calculated. The AD of DM, organic matter (OM), CP, total fat (TF), and α-tocopheryl-acetate were assessed by 2 digestibility trials (at 18-21 and 32-35 d, respectively). Serum protein and plasma α-tocopherol concentrations were assessed at 35 d of age. Final BW, feed intake, carcass, breast, and spleen weight were higher in groups fed LF than HF diets (P = 0.048, P = 0.002, P = 0.039, P DMG-Na-unsupplemented groups (P = 0.011) for both fat levels. During the first digestibility trial (18-21 d), the AD of DM (P = 0.023), OM (P = 0.033), CP (P = 0.030), and α-tocopheryl-acetate (P = 0.036) was higher in the DMG-Na-supplemented group than control. Digestibility of total fat was increased by DMG-Na supplementation in the LF groups (P = 0.038). A trend for improvement of digestibility was observed during the second digestibility trial (32-35 d) for DM (P = 0.089), OM (P = 0.051), and CP (P = 0.063) in DMG-Na groups. Total serum proteins (and relative fractions) were positively influenced by DMG-Na supplementation both in LF and HF diets (P = 0.029). Plasma α-tocopherol concentration was higher in groups fed LF than HF diets (P < 0.001).

Proteins of Bacuri almonds: nutritional value and in vivo digestibility

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Magalli Costa Barbosa Lima e Silva

2014-03-01

Full Text Available Bacuri (Scheelea phalerata Mart. is a type of palm fruit tree widely distributed in the Brazilian Cerrado. The objective of this paper was to study the almonds of bacuri, in their form in natura and processed, focusing on their nutritional value through the profile of amino acids, anti-nutritional factors and in vivo digestibility. Raw and toasted samples of the almond presented a high level of proteins and fiber. Proteins of raw bacuri almond showed no limiting amino acid when compared to the ones recommended by FAO/WHO, and histidine was the most limiting essential amino acid in the toasted almonds. The almond of bacuri does not present anti- nutritional factors. In an assay with rats fed with control (casein, tests (bacuri almond flours and aproteic diets, we verified the quantity of ration ingested and body weight gain, determining the urinary and metabolic nitrogen. Rats treated with the test diets presented inferior values of True Digestibility (DV, (82.9 and 72.3%, respectively for the raw and toasted almonds when compared to the control group (92.3%. The raw bacuri almond presented a superior nutritional value to the one found in the toasted almond.

Determination of denaturated proteins and biotoxins by on-line size-exclusion chromatography-digestion-liquid chromatography-electrospray mass spectrometry

NARCIS (Netherlands)

Carol, J.; Gorseling, M.C.J.K.; Jong, C.F. de; Lingeman, H.; Kientz, C.E.; Baar, B.L.M. van; Irth, H.

2005-01-01

A multidimensional analytical method for the rapid determination and identification of proteins has been developed. The method is based on the size-exclusion fractionation of protein-containing samples, subsequent on-line trypsin digestion and desalination, and reversed-phase high-performance liquid

Protein and starch digestibilities and mineral availability of products developed from potato, soy and corn flour.

Science.gov (United States)

Gahlawat, P; Sehgal, S

1998-01-01

A technique for development of potato flour was standardized. Five products viz. cake, biscuit, weaning food, panjiri and ladoo were prepared incorporating potato flour, defatted soy flour and corn flour. Baking and roasting were the major processing techniques employed for the development of these products. Protein, ash and fat contents of potato flour were almost similar to those of raw potatoes. Significant differences in protein, ash and fat contents of all the products were observed. Protein and starch digestibility of potato flour was significantly higher than that of raw potatoes. Protein digestibility increased by 12 to 17 percent on baking or roasting of products. Processed products had significantly higher starch digestibility and mineral availability compared to raw products. Thus, it can be concluded that roasting and baking are effective means of improving starch and protein digestibility and mineral availability of products.

Intestinal digestibility of enriched-protein fodders measured by ...

African Journals Online (AJOL)

Ruminal, intestinal and total tract digestibility of dry matter (DM) and crude protein (CP) of leucaena (Leucaena leucocephala), Madras thorn (Pithecellobium dulce) and moringa (Moringa oleifera) fodders were measured in this study, using nylon bag and mobile bag techniques. Three cattle were fitted with permanent ...

Effect of Electron Beam Irradiation on Degradability Coefficients and Ruminalpostruminal Digestibility of Dry Matter and Crude Protein of some Plant Protein Sources

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gasem tahan

2016-06-01

Full Text Available Effect of electron beam irradiation on degradability coefficients and ruminal- postruminal digestibility of dry matter and crude protein of soybean meal, canola meal and Lathyrus sativus seed, irradiated at doses of 50, 100 and 150 kGy was investigated. Ruminal degradability of dry matter and crude protein was determined by in situ method using two cannulated Holstein heifers. Ruminal- postruminal digestibility of dry matter and crude protein was determined by in situ (nylon bag-in vitro (daisy digestor techniques. Data analyzed using SAS software as randomized completely design and the treatment means were compared using Tukey test. The results indicated that irradiation had no effect on dry matter, ether extract and ash content of feeds. In soybean meal, washout fraction and potentially degradable fraction of dry matter and crude protein was higher and lower at dose of 150 kGy irradiation than other treatments, respectively, and degradation rate constant and ruminal effective degradability of dry matter and crude protein was lower at all doses of irradiation than untreated soybean meal. In canola meal, irradiation at doses of 50 and 100 kGy decreased washout fraction and increased potentially degradable fraction of crude protein compared with untreated canola meal. In Lathyrus sativus seed, only potentially degradable fraction of dry matter and crude protein was lower at dose of 150 kGy irradiation than untreated Lathyrus sativus seed. Ruminal digestibility of crude protein decreased in soybean meal at doses of 100 and 150 kGy irradiation and for canola meal at all doses of irradiation than untreated samples. Total tract digestibility of crude protein decreased in soybean meal at dose of 150 kGy irradiation and for canola meal at all doses of irradiation than untreated samples. In Lathyrus sativus seed, ruminal-postruminal digestibility and total tract digestibility of dry matter increased at doses of 100 and 150 kGy irradiation than untreated

Stability and in vitro digestibility of emulsions containing lecithin and whey proteins.

Science.gov (United States)

Mantovani, Raphaela Araujo; Cavallieri, Ângelo Luiz Fazani; Netto, Flavia Maria; Cunha, Rosiane Lopes

2013-09-01

The effect of pH and high-pressure homogenization on the properties of oil-in-water (O/W) emulsions stabilized by lecithin and/or whey proteins (WPI) was evaluated. For this purpose, emulsions were characterized by visual analysis, droplet size distribution, zeta potential, electrophoresis, rheological measurements and their response to in vitro digestion. Lecithin emulsions were stable even after 7 days of storage and WPI emulsions were unstable only at pH values close to the isoelectric point (pI) of proteins. Systems containing the mixture of lecithin and WPI showed high kinetic instability at pH 3, which was attributed to the electrostatic interaction between the emulsifiers oppositely charged at this pH value. At pH 5.5 and 7, the mixture led to reduction of the droplet size with enhanced emulsion stability compared to the systems with WPI or lecithin. The stability of WPI emulsions after the addition of lecithin, especially at pH 5.5, was associated with the increase of droplet surface charge density. The in vitro digestion evaluation showed that WPI emulsion was more stable against gastrointestinal conditions.

The foodomics approach for the evaluation of protein bioaccessibility in processed meat upon in vitro digestion.

Science.gov (United States)

Bordoni, Alessandra; Laghi, Luca; Babini, Elena; Di Nunzio, Mattia; Picone, Gianfranco; Ciampa, Alessandra; Valli, Veronica; Danesi, Francesca; Capozzi, Francesco

2014-06-01

The present work describes a foodomics protocol coupling an in vitro static simulation of digestion to a combination of omics techniques, to grant an overview of the protein digestibility of a meat-based food, namely Bresaola. The proteolytic activity mediated by the digestive enzymes is evaluated through Bradford and SDS-PAGE assays, combined to NMR relaxometry and spectroscopy, to obtain information ranging from the microscopic to the molecular level, respectively. The simple proteomics tool adopted here points out that a clear increase of bioaccessible proteins occurs in the gastric phase, rapidly disappearing during the following duodenal digestion. However, SDS-PAGE and the Bradford assay cannot follow the fate of the digested proteins when the products are sized meat matrix. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Influence of feeding varying crude protein and digestible energy ...

African Journals Online (AJOL)

Influence of feeding varying crude protein and digestible energy levels on the development of individual muscles, rate of lean and fat deposition in pigs reared from 9 to 60kg liveweight in a humid tropical environment.

Change of the structure and the digestibility of myofibrillar proteins in Nanjing dry-cured duck during processing.

Science.gov (United States)

Du, Xiaojing; Sun, Yangying; Pan, Daodong; Wang, Ying; Ou, Changrong; Cao, Jinxuan

2018-06-01

To investigate the change of bioavailability and structure of myofibrillar proteins during Nanjing dry-cured duck processing, carbonyl content, sulfhydryl (SH) group, disulfide (SS) group, sodium dodecyl sulfate polyacrylamide gel electrophoresis, surface hydrophobicity, secondary structures and in vitro digestibility were determined. During processing, carbonyl content and surface hydrophobicity increased; SH turned into SS group; α-helix turned into β-sheet and random coil fractions. Protein degradation occurred during dry-curing and drying-ripening stages. The in vitro digestibility of pepsin and pancreatic proteases increased during the salt curing stage and decreased during the drying-ripening stage. The increase of digestibility could be attributed to the mild oxidation, degradation and unfolding of proteins while the decrease of digestibility was related to the intensive oxidation and aggregation of proteins. Protein degradation was not a main factor of digestibility during the drying-ripening stage. Results demonstrated that the bioavailability loss of myofibrillar proteins in Nanjing dry-cured duck occurred during the stage of drying-ripening instead of curing. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Label-Free Quantitative Analysis of Mitochondrial Proteomes Using the Multienzyme Digestion-Filter Aided Sample Preparation (MED-FASP) and "Total Protein Approach".

Science.gov (United States)

Wiśniewski, Jacek R

2017-01-01

Determination of proteome composition and measuring of changes in protein titers provide important information with a substantial value for studying mitochondria.This chapter describes a workflow for the quantitative analysis of mitochondrial proteome with a focus on sample preparation and quantitative analysis of the data. The workflow involves the multienzyme digestion-filter aided sample preparation (MED-FASP) protocol enabling efficient extraction of proteins and high rate of protein-to-peptide conversion. Consecutive protein digestion with Lys C and trypsin enables generation of peptide fractions with minimal overlap, largely increases the number of identified proteins, and extends their sequence coverage. Abundances of proteins identified by multiple peptides can be assessed by the "Total Protein Approach."

A capillary monolithic trypsin reactor for efficient protein digestion in online and offline coupling to ESI and MALDI mass spectrometry.

Science.gov (United States)

Spross, Jens; Sinz, Andrea

2010-02-15

We describe the preparation of a capillary trypsin immobilized monolithic enzyme reactor (IMER) for a rapid and efficient digestion of proteins down to the femtomole level. Trypsin was immobilized on a poly(glycidyl methacrylate-co-acrylamide-co-ethylene glycol dimethycrylate) monolith using the glutaraldehyde technique. Digestion efficiencies of the IMER were evaluated using model proteins and protein mixtures as well as chemically cross-linked lysozyme regarding the addition of denaturants and increasing digestion temperature. The trypsin IMER described herein is applicable for the digestion of protein mixtures. Even at a 1000-fold molar excess of one protein, low-abundance proteins are readily identified, in combination with MS/MS analysis. An online setup of the IMER with reversed phase nano-HPLC separation and nano-ESI-MS/MS analysis was established. The great potential of the trypsin IMER for proteomics applications comprise short digestion times in the range of seconds to minutes, in addition to improved digestion efficiencies, compared to in-solution digestion.

In vivo assessment of the ability of condensed tannins to interfere with the digestibility of plant protein in sheep

Energy Technology Data Exchange (ETDEWEB)

Andrabi, S.M.; Ritchie, M.M.; Stimson, C.; Horadagoda, A.; Hyde, M.; McNeill, D.M. [MC Franklin Laboratory, Faculty of Veterinary Science, University of Sydney, Camden, NSW (Australia)]. E-mail: karalue@bigpond.net.au

2005-08-19

To assess the effect of condensed tannin (CT) astringency on the digestibility of protein post-ruminally, CT were purified from four types (accessions) of Mulga (Acacia aneura), and a Leucaena pallida and dosed into sheep as complexes with {sup 15}N-plant protein (tannin-protein complexes, TPC), together with an indigestible marker, chromium-EDTA (Cr-EDTA). Each CT treatment dose comprised 12 mg CT, 10 mg {sup 15}N-protein, and 2.77 mg of Cr. A protein-only control (same as the other TPC solutions but without any CT) treatment was also included to make a total of six treatments. Treatments were applied in two 6 x 6 Latin Square designs with 72 h between each infusion for each sheep. In the first, the solutions were infused post-ruminally via an abomasal cannula. In the second they were dosed directly into the mouth following an intra-nasal dose of an analogue of vasopressin in an attempt to stimulate the oesophageal groove reflex to direct the solutions more efficiently toward the small intestine. Results showed no detectable effect of CT type on the in vivo digestibility of the {sup 15}N-protein. Protein digestibilities were uniformly high, indicative of complete dissociation of the TPC. There was no correlation between protein digestibility, mouth to faeces, and protein digestibility, abomasum to faeces (P > 0.05). In vivo digestibility was also uncorrelated with CT astringencies defined in vitro (P > 0.05). Astringency in vitro was defined as the mg of CT required to achieve half-maximal precipitation of 0.5 mg of protein (bovine serum albumin). In vitro, the most astringent CT (A. aneura 883558), had at least 1.6 times the astringency of the weakest CT (A. aneura 842394). The A. aneura with the weakest CT also contained less than 1/3 the total amount of CT/g leaf dry matter than that with the strongest, highlighting the scope for selection of more nutritionally useful types of A. aneura. Limitations of the in vivo protocol used are discussed and it is concluded

Effects of dietary protein level on nutrients digestibility and reproductive performance of female mink (Neovison vison during gestation

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Qingkui Jiang

2015-06-01

Full Text Available The objective of this study was to determine whether nutrient digestibility and reproductive performance of pregnant mink (Neovison vison were affected by different dietary protein levels. One hundred and twenty female mink were randomly assigned to four groups, receiving diets of fresh material with different protein levels. The dietary protein levels, expressed as percentage of dry matter (DM, were 32, 36, 40 and 44% respectively. These values corresponded to average 320, 360, 400 and 440 g protein/kg DM, respectively. Results were as follows. All of crude protein digestibility, nitrogen (N intake, N retention increased along with dietary protein level increasing. Low protein level (32% significantly reduced the above indicators (P < 0.05. DM digestibility and ether extract digestibility were not affected by dietary protein level. Results of mated females, barren females, kids per litter, live born kids per mated female, birth survival rate, and birth weight showed that mink achieved optimal reproductive performance when dietary protein level was 36%. In conclusion, dietary protein was anticipated to significantly influence some nutrients' utilization. Adopting the appropriate dietary protein level allow better reproduction performance. The most preferable reproductive performance was achieved when diet contained 275.5 g digestible protein per kg DM for female mink in gestation.

Impact of Protein Gel Porosity on the Digestion of Lipid Emulsions.

Science.gov (United States)

Sarkar, Anwesha; Juan, Jean-Marc; Kolodziejczyk, Eric; Acquistapace, Simone; Donato-Capel, Laurence; Wooster, Tim J

2015-10-14

The present study sought to understand how the microstructure of protein gels impacts lipolysis of gelled emulsions. The selected system consisted of an oil-in-water (o/w) emulsion embedded within gelatin gels. The gelatin-gelled emulsions consisted of a discontinuous network of aggregated emulsion droplets (mesoscale), dispersed within a continuous network of gelatin (microscale). The viscoelastic properties of the gelled emulsions were dominated by the rheological behavior of the gelatin, suggesting a gelatin continuous microstructure rather than a bicontinuous gel. A direct relationship between the speed of fat digestion and gel average mesh size was found, indicating that the digestion of fat within gelatin-gelled emulsions is controlled by the ability of the gel's microstructure to slow lipase diffusion to the interface of fat droplets. Digestion of fat was facilitated by gradual breakdown of the gelatin network, which mainly occurred via surface erosion catalyzed by proteases. Overall, this work has demonstrated that the lipolysis kinetics of gelled emulsions is driven by the microstructure of protein gels; this knowledge is key for the future development of microstructures to control fat digestion and/or the delivery of nutrients to different parts of the gastrointestinal tract.

Simplified sample preparation method for protein identification by matrix-assisted laser desorption/ionization mass spectrometry: in-gel digestion on the probe surface

DEFF Research Database (Denmark)

Stensballe, A; Jensen, Ole Nørregaard

2001-01-01

/ionization-time of flight mass spectrometry (MALDI-TOF-MS) is used as the first protein screening method in many laboratories because of its inherent simplicity, mass accuracy, sensitivity and relatively high sample throughput. We present a simplified sample preparation method for MALDI-MS that enables in-gel digestion...... for protein identification similar to that obtained by the traditional protocols for in-gel digestion and MALDI peptide mass mapping of human proteins, i.e. approximately 60%. The overall performance of the novel on-probe digestion method is comparable with that of the standard in-gel sample preparation...... protocol while being less labour intensive and more cost-effective due to minimal consumption of reagents, enzymes and consumables. Preliminary data obtained on a MALDI quadrupole-TOF tandem mass spectrometer demonstrated the utility of the on-probe digestion protocol for peptide mass mapping and peptide...

Effect of meat cooking on physicochemical state and in vitro digestibility of myofibrillar proteins.

Science.gov (United States)

Santé-Lhoutellier, Veronique; Astruc, Thierry; Marinova, Penka; Greve, Eleonore; Gatellier, Philippe

2008-02-27

The effect of meat cooking was measured on myofibrillar proteins from bovine M. Rectus abdominis. The heating treatment involved two temperatures (100 degrees C during 5, 15, 30, and 45 min and 270 degrees C during 1 min). Protein oxidation induced by cooking was evaluated by the level of carbonyl and free thiol groups. Structural modifications of proteins were assessed by the measurement of their surface hydrophobicity and by their aggregation state. With the aim of evaluating the impact of heat treatment on the digestive process, myofibrillar proteins were then exposed to proteases of the digestive tract (pepsin, trypsin, and alpha-chymotrypsin) in conditions of pH and temperature that simulate stomach and duodenal digestion. Meat cooking affected myofibrillar protein susceptibility to proteases, with increased or decreased rates, depending on the nature of the protease and the time/temperature parameters. Results showed a direct and quantitative relationship between protein carbonylation (p<0.01) and aggregation (p<0.05) induced by cooking and proteolytic susceptibility to pepsin. However, no such correlations have been observed with trypsin and alpha-chymotrypsin.

The Effects of Fortification of Legumes and Extrusion on the Protein Digestibility of Wheat Based Snack.

Science.gov (United States)

Patil, Swapnil S; Brennan, Margaret A; Mason, Susan L; Brennan, Charles S

2016-04-06

Cereal food products are an important part of the human diet with wheat being the most commonly consumed cereal in many parts of the world. Extruded snack products are increasing in consumer interest due to their texture and ease of use. However, wheat based foods are rich in starch and are associated with high glycaemic impact products. Although legume materials are generally rich in fibre and protein and may be of high nutritive value, there is a paucity of research regarding their use in extruded snack food products. The aim of this study was to prepare wheat-based extrudates using four different legume flours: lentil, chickpea, green pea, and yellow pea flour. The effects of adding legumes to wheat-based snacks at different levels (0%, 5%, 10%, and 15%) during extrusion were investigated in terms of protein digestibility. It was observed that fortification of snacks with legumes caused a slight increase in the protein content by 1%-1.5% w/w, and the extrusion technique increased the protein digestibility by 37%-62% w/v. The product developed by extrusion was found to be low in fat and moisture content.

The Effects of Fortification of Legumes and Extrusion on the Protein Digestibility of Wheat Based Snack

Directory of Open Access Journals (Sweden)

Swapnil S. Patil

2016-04-01

Full Text Available Cereal food products are an important part of the human diet with wheat being the most commonly consumed cereal in many parts of the world. Extruded snack products are increasing in consumer interest due to their texture and ease of use. However, wheat based foods are rich in starch and are associated with high glycaemic impact products. Although legume materials are generally rich in fibre and protein and may be of high nutritive value, there is a paucity of research regarding their use in extruded snack food products. The aim of this study was to prepare wheat-based extrudates using four different legume flours: lentil, chickpea, green pea, and yellow pea flour. The effects of adding legumes to wheat-based snacks at different levels (0%, 5%, 10%, and 15% during extrusion were investigated in terms of protein digestibility. It was observed that fortification of snacks with legumes caused a slight increase in the protein content by 1%–1.5% w/w, and the extrusion technique increased the protein digestibility by 37%–62% w/v. The product developed by extrusion was found to be low in fat and moisture content.

Microbial and nutritional regulation of high-solids anaerobic mono-digestion of fruit and vegetable wastes.

Science.gov (United States)

Mu, Hui; Li, Yan; Zhao, Yuxiao; Zhang, Xiaodong; Hua, Dongliang; Xu, Haipeng; Jin, Fuqiang

2018-02-01

The anaerobic digestion of single fruit and vegetable wastes (FVW) can be easily interrupted by rapid acidogenesis and inhibition of methanogen, and the digestion system tends to be particularly unstable at high solid content. In this study, the anaerobic digestion of FVW in batch experiments under mesophilic condition at a high solid concentration of 10% was successfully conducted to overcome the acidogenesis problem through several modifications. Firstly, compared with the conventional anaerobic sludge (CAS), the acclimated anaerobic granular sludge (AGS) was found to be a better inoculum due to its higher Archaea abundance. Secondly, waste activated sludge (WAS) was chosen to co-digest with FVW, because WAS had abundant proteins that could generate intermediate ammonium. The ammonium could neutralize the accumulated volatile fatty acids (VFAs) and prevent the pH value of the digestion system from rapidly decreasing. Co-digestion of FVW and WAS with TS ratio of 60:40 gave the highest biogas yield of 562 mL/g-VS and the highest methane yield of 362 mL/g-VS. Key parameters in the digestion process, including VFAs concentration, pH, enzyme activity, and microbial activity, were also examined.

Energy efficiency of digestible protein, fat and carbohydrate utilisation for growth in rainbow trout and Nile tilapia.

Science.gov (United States)

Schrama, Johan W; Haidar, Mahmoud N; Geurden, Inge; Heinsbroek, Leon T N; Kaushik, Sachi J

2018-04-01

Currently, energy evaluation of fish feeds is performed on a digestible energy basis. In contrast to net energy (NE) evaluation systems, digestible energy evaluation systems do not differentiate between the different types of digested nutrients regarding their potential for growth. The aim was to develop an NE evaluation for fish by estimating the energy efficiency of digestible nutrients (protein, fat and carbohydrates) and to assess whether these efficiencies differed between Nile tilapia and rainbow trout. Two data sets were constructed. The tilapia and rainbow data set contained, respectively, eight and nine experiments in which the digestibility of protein, fat and energy and the complete energy balances for twenty-three and forty-five diets was measured. The digestible protein (dCP), digestible fat (dFat) and digestible carbohydrate intakes (dCarb) were calculated. By multiple regression analysis, retained energy (RE) was related to dCP, dFat and dCarb. In tilapia, all digestible nutrients were linearly related to RE (Pefficiency of dCP, dFat and dCarb was 49, 91 and 66 %, respectively, showing large similarity with pigs. Tilapia and trout had similar energy efficiencies of dCP (49 v. 57 %) and dFat (91 v. 84 %), but differed regarding dCarb.

Crude protein, fibre and phytic acid in vitro digestibility of selected legume and buckwheat samples

Directory of Open Access Journals (Sweden)

Petra Vojtíšková

2013-01-01

Full Text Available The aim of this study was to determine crude protein, fibre and phytic acid in vitro digestibility of selected legumes and buckwheat products. All analyses except the phytic acid contents were performed in the line with the Commission Regulation (EC No. 152/2009. A modified version of Holt’s Method was used for phytic acid (phytate determination. None of all samples contained more than 11% of moisture. Soybeans are rich in crude protein; they contain nearly 40% of this compound. The content of crude protein in buckwheat flours was about 14%. The highest amount of phytate was found in common beans and soybeans-about 2 g/100 g of dry matter. On the other hand, the lowest phytate content was observed in buckwheat pasta (F. esculentum groats was 1.9 g per 100 g of dry matter. In vitro digestibility was determined using an incubator Daisy and pepsin enzymes and the combination of pepsin and pancreatin. The highest coefficient of crude protein digestibility was discovered to be in peels and wholemeal flour. The greatest fibre digestibility coefficients were obtained for peels, which contain about 65% of fibre in their dry matter. When pepsin was used, a higher phytic acid digestibility coefficient for G. max, Ph. vulgaris, peels, flour, groats and broken groats was observed; while when the combination of pepsin and pancreatin was used, higher phytic acid digestibility coefficients for peas, lentil and wholemeal flour were observed.

Protein digestion: An overview of the available techniques and recent developments

NARCIS (Netherlands)

Switzar, L.; Giera, M.; Niessen, W.M.A.

2013-01-01

Several proteomics approaches are available that are defined by the level (protein or peptide) at which analysis takes place. The most widely applied method still is bottom-up proteomics where the protein is digested into peptides that can be efficiently analyzed with a wide range of LC-MS or

Nutrient Intake and Digestibility of Cynomolgus Monkey (Macaca fascicularis Fed with High Soluble Carbohydrate Diet: A Preliminary Study

Directory of Open Access Journals (Sweden)

DEWI APRI ASTUTI

2009-12-01

Full Text Available High carbohydrate as obese diet is not yet available commercially for monkeys. Therefore, this preliminary study was to carry out nutrient intake and digestibility of cynomolgus monkeys (Macaca fascicularis fed with high soluble carbohydrate diet compared to monkey chow. Five adult female macaques (average body weight 2.67 kg were made to consume freshly diet. Commercial monkey chows (contains 3500 cal/g energy and 35% starch were fed to three adult females (average body weight 3.62 kg. Nutrient intakes and digestibility parameters were measured using modified metabolic cages. Result showed that average of protein, fat, starch, and energy intakes in treatment diet were higher than control diet (T-test. Fat intake in the treatment diet was three times higher, while starch and energy intakes were almost two times higher than monkey chow. Digestibility percentage of all nutrients were the same in both diets except for the protein. The study concludes that the freshly prepared high sugar diet was palatable and digestible for the cynomolgus monkeys. Further studies are in progress to develop obese diet high in energy content based on fat and source of starch treatments.

The Effect of Gel Microstructure on Simulated Gastric Digestion of Protein Gels

NARCIS (Netherlands)

Opazo-Navarrete, Mauricio; Altenburg, Marte D.; Boom, Remko M.; Janssen, Anja E.M.

2018-01-01

The objective of this study was to analyse the impact of the gel structure obtained by different heat-induced temperatures on the in vitro gastric digestibility at pH 2. To achieve this, gels were prepared from soy protein, pea protein, albumin from chicken egg white and whey protein isolate at

The effect of replacing lactose by starch on protein and fat digestion in milk-fed veal calves.

Science.gov (United States)

Pluschke, A M; Gilbert, M S; Williams, B A; van den Borne, J J G C; Schols, H A; Gerrits, W J J

2016-08-01

Replacing dairy components from milk replacer (MR) with vegetable products has been previously associated with decreased protein and fat digestibility in milk-fed calves resulting in lower live weight gain. In this experiment, the major carbohydrate source in MR, lactose, was partly replaced with gelatinized corn starch (GCS) to determine the effect on protein and fat digestibility in milk-fed calves. In total, 16 male Holstein-Friesian calves received either MR with lactose as the carbohydrate source (control) or 18% GCS at the expense of lactose. In the adaptation period, calves were exposed to an increasing dose of GCS for 14 weeks. The indigestible marker cobalt ethylenediaminetetraacetic acid was incorporated into the MR for calculating apparent nutrient digestibility, whereas a pulse dose of chromium (Cr) chloride was fed with the last MR meal 4 h before slaughter as an indicator of passage rates. The calves were anesthetized and exsanguinated at 30 weeks of age. The small intestine was divided in three; small intestine 1 and 2 (SI1 and SI2, respectively) and the terminal ileum (last ~100 cm of small intestine) and samples of digesta were collected. Small intestinal digesta was analysed for α-amylase, lipase and trypsin activity. Digestibility of protein was determined for SI1, SI2, ileum and total tract, whereas digestibility of fat was determined for SI1, SI2 and total tract. Apparent protein digestibility in the small intestine did not differ between treatments but was higher in control calves at total tract level. Apparent crude fat digestibility tended to be increased in SI1 and SI2 for GCS calves, but no difference was found at total tract level. Activity of α-amylase in SI2 and lipase in both SI1 and SI2 was higher in GCS calves. Activity of trypsin tended to be higher in control calves and was higher in SI1 compared with SI2. A lower recovery of Cr in SI2 and a higher recovery of Cr in the large intestine suggest an increased rate of passage for GCS

Nutritive utilization of protein and digestive utilization of fat in two commercial diets designed for clinical enteral nutrition.

Science.gov (United States)

Alférez, M J; Campos, M S; Barrionuevo, M; López-Aliaga, I

1990-01-01

The digestive and metabolic utilization of protein (50% lactoalbumin + 50% casein) and fat (43.0% butter, 29.5% olive oil, 14.7% soy oil, 9.8% MCT and 3.0% lecithin) provided by two commercial diets used in clinical enteral nutrition (normoproteic, 16.1% protein and 20.8% fat, and hyperproteic, 23.1% protein and 14.9% fat), was studied in adult rats (mean body weight 180 g). The diet containing the greater amount of protein improved the digestive utilization of nitrogen, and although nitrogen retention was optimal, it failed to rise further when the dietary protein supply was increased. The digestive utilization of fat in both diets was excellent.

Feeding Value of Silybum marianum for Sheep and its Effect on Fiber and Protein Digestion

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Ali Mojadam

2016-04-01

Full Text Available Introduction Due to scarcity of forage and water resources and high feed prices in Iran, it seems that the utilization of native and cheap forage resources for ruminants is important. The Milk thistle (Silybum marianum is distributed in different regions of Iran included: Gonbad Kavoos, Gorgan, Nodeh Kalardasht, Dareh Hezareh, Dasht Mugan, Poshtkoh, Mollassani, Shush, Hamidieh, Ramhormuz, Izeh and Kazeroon. The Silybum marianum seed extract and whole plant contain many compounds including Silybin A and B, Silychristin, Apigenin, deoxy silydianin (flavonolignans. Seeds of this plant has about 20 to 25 percent oil, which oleic acids (31.85 %, linoleic acid (45.36 % percent and palmitic acid (8.25 % are the major fatty acids of Silybum marianum seed. Also, the Silybum marianum contains flavonoids and anti-nutritional compounds such as tannins and nitrates. Tannins, unsaturated oils and other anti-nutritional compounds may have negative effects on the digestion of fiber and protein fractions. Tannins can make complexes with large number of nutrients, such as carbohydrates, proteins, bacterial cell membrane protein and carbohydrates, and even digestive enzymes. The Silybum marianum plants are native to northern areas of Ahvaz and abundantly growth as self-propelled. The farm animals in these area (sheep, goats, camels, water buffalo and native cows, etc. graze this plant as well as the manual feeding, but there is little known about its effects on the health, performance and digestibility of nutrients (in particular on the fiber and protein, due to existing the tannin and unsaturated oils in it in those animals, and no research work has been done about Silybum marianum. Therefore, this experiment was conducted to determine the feeding value of Silybum marianum and to measure its effects on rumen fermentation and digestion of fiber (straw and protein constituents (soybean meal feedstuff in Arabi sheep. Materials and Methods Twelve male Arabi sheep

Changes in protein and starch digestibility in sorghum flour during heat-moisture treatments.

Science.gov (United States)

Vu, Thanh-Hien; Bean, Scott; Hsieh, Chao-Feng; Shi, Yong-Cheng

2017-11-01

Heat-moisture treatment (HMT) has been used to modify properties of sorghum starches. However, information is limited on the effects of HMT on the digestibility of starch and the concurrent changes in protein in sorghum flour. The objectives of this research were to identify heat-moisture conditions to increase the resistant starch (RS) content of sorghum flour and investigate changes in sorghum proteins and starch structure. Sorghum flours with different moisture contents (0, 125, 200, and 300 g kg -1 w.b.) were heated at three temperatures (100, 120 and 140 °C) and times (1, 2 and 4 h). HMT of sorghum flour increased its RS level. The flour treated at 200 g kg -1 moisture and 100 °C for 4 h had a high RS content (221 g kg -1 vs. 56 g kg -1 for the untreated flour). Starch was not gelatinized when sorghum flours heated at moisture content of 200 g kg -1 or below. Sorghum protein digestibility and solubility decreased during HMT. The increase in RS of sorghum flour upon HMT was attributed to enhanced amylose-lipid complexes and heat induced structural changes in its protein fraction. HMT can be used to increase RS content in sorghum flour without gelatinizing its starch, thereby providing sorghum flour with unique food applications. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Using guanidine-hydrochloride for fast and efficient protein digestion and single-step affinity-purification mass spectrometry

DEFF Research Database (Denmark)

Poulsen, Jon Wriedt; Madsen, Christian Toft; Young, Clifford

2013-01-01

be optimally completed within 30 min with endoprotease Lys-C. No chemical artifacts were introduced when samples were incubated in Gnd-HCl at 95 °C, making Gnd-HCl an appropriate digestion buffer for shotgun proteomics. Current methodologies for investigating protein-protein interactions (PPIs) often require......Protein digestion is an integral part of the "shotgun" proteomics approach and commonly requires overnight incubation prior to mass spectrometry analysis. Quadruplicate "shotgun" proteomic analysis of whole yeast lysate demonstrated that Guanidine-Hydrochloride (Gnd-HCl) protein digestion can....... To validate the Gnd-HCl approach, label-free PPI analysis of several GFP-tagged yeast deubiquitinating enzymes was performed. The identification of known interaction partners demonstrates the utility of the optimized Gnd-HCl protocol that is also scalable to the 96 well-plate format....

The effect of gamma irradiation on the chemical composition and digestible crude protein of poultry excreta

International Nuclear Information System (INIS)

Al-Masri, M.R.

1994-06-01

The changes in the chemical composition, digestible crude protein and cell-wall constituents for two types of excreta of laying hens were studied. In type I, excreta were dried at 170-180 C for 10 minutes whereas in type II dried at 55-60 C for several days. Each type was divided into two parts, the first stored for 3 months with the control. The second part was irradiated by gamma irradiation at 100 KGy and stored for 3 months with the control. The results indicated that here was significant decrease in the crude fibre (CF), NDF and ADF between the samples and the control, for the types I and II where CF, NDF and ADF values, before and after storage, decreased by 12%, 5% and 6%, respectively, ADL values decreased by 8% (I) and 3%(II). Hemicellulose and soluble carbohydrate (NFE) values increased by 5% and 7% for types I and II respectively as a result of irradiation in comparison to the control before and after storage. Gamma irradiation had no effect on crude protein, crude fat, crude ash and digested crude protein for types I and II before and after storage. Drying type I at high temperature in comparison to type II, before and after storage, decreased the crude protein values by 16%. Digested crude protein and CF, decreased 12% and NDF by 7%. Storage of excreta after drying had no effect on the chemical changes due to irradiation for types I and II. (author). 23 refs., 6 figs., 7 tabs

DIGESTIBLE VALINE REQUIREMENTS IN LOW-PROTEIN DIETS FOR BROILERS CHICKS

Directory of Open Access Journals (Sweden)

GR Nascimento

Full Text Available ABSTRACT Three experiments were carried out to evaluate the levels of digestible valine in diets with reduced crude protein on the performance, carcass yield and muscle fiber diameter of male broilers during the pre-starter (1 to 8 d of age, starter (9 to 21 d of age and grower phases (21 to 42 d of age. A total of 1,080 chickens in the pre-starter phase, 900 in the starter phase and 864 in the grower phase were distributed in a completely randomized design with six treatments, consisting of a control positive diet (C+ and diets with 2 percentage points (p.p. reduction of crude protein level and five graded levels of digestible valine (Val, with six replicates of 30, 25 and 24 birds per experimental unit, respectively. The recommended level of TID Val in the low-protein diets for broilers in the pre-starter, starter and grower stages were 1.028; 0.905 and 0.789%, respectively. The reduction of 2 percentage points of the crude protein level in diets based on corn and soybean meal impaired (p ≤0.05 the feed conversion ratio in the starter and grower stages. Likewise, the reduced-protein diets decreased (p ≤0.05 muscle fiber diameter, but did not affect (p> 0.05 carcass and parts yields, or abdominal fat percentage at 42 days.

Nutrient digestibility response to sugarcane bagasse addition and corn particle size in normal and high Na diets for broilers.

Science.gov (United States)

Kheravii, S K; Swick, R A; Choct, M; Wu, S-B

2018-04-01

Improving diet digestibility is important to the broiler industry. Therefore, this study focused on optimizing the physical structure of feed ingredients and addition of dietary fiber as strategies to improve nutrient digestibility in low and high sodium diets. A total of 672 day-old Ross 308 male broilers was allocated to 48 pens using a 2 × 2 × 2 factorial arrangement of treatments with 2 particle sizes of corn (coarse 3,576 μm or fine 1,113 μm geometric mean diameter), 2 levels of sugarcane bagasse (SB) (0 or 2%), and 2 levels of Na (0.16 or 0.4%). Protein digestibility coefficient was measured using pooled distal ileal digesta of 3 birds per pen on d 24. Meanwhile, starch and gross energy digestibility coefficients were measured using pooled duodenal, distal jejunal, and distal ileal digesta of 3 birds per pen on d 24. Coarsely ground corn (CC) resulted in improved ileal protein digestibility (P digestibility in the duodenum (P digestibility in distal ileum (P digestibility (P digestibility only in birds fed the diet with finely ground corn (FC) and 0.16% Na. These findings demonstrate that SB and CC are able to improve nutrient digestibility. It can be recommended for the poultry industry to use SB and coarsely ground corn in feed to improve the utilization of nutrients.

Digested disorder

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a series of reader’s digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28516028

Protein Digestion and Quality of Goat and Cow Milk Infant Formula and Human Milk Under Simulated Infant Conditions.

Science.gov (United States)

Maathuis, Annet; Havenaar, Robert; He, Tao; Bellmann, Susann

2017-12-01

The aim of this study was to determine the kinetics of true ileal protein digestion and digestible indispensable amino acid score (DIAAS) of a goat milk-based infant formula (GIF), a cow milk-based infant formula (CIF), and human milk (HM). The GIF, CIF, and HM were investigated in an in vitro gastrointestinal model simulating infant conditions. Digested compounds were dialyzed from the intestinal compartment as bioaccessible fraction. Dialysate was collected in 15 to 60-minute periods for 4 hours. True ileal protein digestibility and DIAAS were determined as bioaccessible nitrogen (N) and amino acids. N bioaccessibility from the GIF showed similar kinetics to that of HM. The CIF showed a delay in N bioaccessibility versus the GIF and HM. In the 1st hour of digestion, N bioaccessibility was 19.9% ± 3.5% and 23.3% ± 1.3% for the GIF and HM, respectively, and 11.2% ± 0.6% for CIF (P < 0.05 vs HM). In the 3rd hour of digestion, the N bioaccessibility was higher (P < 0.05) for the CIF (28.9% ± 1.2%) than for the GIF (22.5% ± 1.6%) and HM (20.6% ± 1.0%). After 4 hours, the true ileal protein digestibility of the GIF, CIF, and HM was 78.3% ± 3.7%, 73.4% ± 2.7%, and 77.9% ± 4.1%, respectively. The DIAAS for the GIF, CIF, and HM for 0- to 6-month-old infants was 83%, 75%, and 77% for aromatic AA. The protein quality is not different between the GIF, CIF, and HM, but the kinetics of protein digestion of the GIF is more comparable to that of HM than that of the CIF.

Anaerobic digestion of agricultural wastes

Energy Technology Data Exchange (ETDEWEB)

Hobson, P N

1984-01-01

Farm digesters can operate satisfactorily and have a useful role on the farm. Gas production from the farm digester treating animal slurries could be boosted by adding silage liquid, old potatoes, waste cabbages and other crop wastes to the slurry, although the energy economics of maceration have not been calculated. Pollution control and types of digester are discussed. Uses of digested slurry other than for fertilizers are being tested - as protein supplement to farm animal feeds, silage making, hydroponics, fish farming and growing of worms on algae. Overall, digestion could be a contributor to power requirements especially in countries with high all year round crop production.

Digested disorder: Quarterly intrinsic disorder digest (January/February/March, 2013).

Science.gov (United States)

Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is blooming. A simple PubMed search for "intrinsically disordered protein OR natively unfolded protein" returns about 1,800 hits (as of June 17, 2013), with many papers published quite recently. To keep interested readers up to speed with this literature, we are starting a "Digested Disorder" project, which will encompass a series of reader's digest type of publications aiming at the objective representation of the research papers and reviews on intrinsically disordered proteins. The only two criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest covers papers published during the period of January, February and March of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Nutrient digestibility and evaluation of protein and carbohydrate fractionation of citrus by-products

DEFF Research Database (Denmark)

Lashkari, Saman; Taghizadeh, Akbar

2013-01-01

The protein and carbohydrate fractionation and nutrient digestibility of citrus by‐products were determined. Ruminal, intestinal and total tract CP disappearance values were measured by a modified three‐step (MTSP) method and in vitro CP disappearance method (IVCP). Test feeds were orange pulp (OP...... to the results, it could be concluded that citrus by‐products have high nutritive value and also, the in vitro techniques can be easily used to determine of the nutritive value of citrus by‐products....

In vitro chemopreventive properties of peptides released from quinoa (Chenopodium quinoa Willd.) protein under simulated gastrointestinal digestion.

Science.gov (United States)

Vilcacundo, Rubén; Miralles, Beatriz; Carrillo, Wilman; Hernández-Ledesma, Blanca

2018-03-01

Because of the continuous and direct interaction between the digestive tract and foods, dietary compounds represent an interesting source of chemopreventive agents for gastrointestinal health. In this study, the influence of a standardized static in vitro gastrointestinal digestion model on the release of peptides with chemopreventive potential from quinoa protein was investigated. Gastroduodenal digests and fractions collected by ultrafiltration were evaluated for their in plate oxygen radical absorbance capacity and in vitro colon cancer cell viability inhibitory activity. Highest effects were observed in the digests obtained during the intestinal phase, with fraction containing peptides 5kDa showing the greatest anti-cancer effects. Seventeen potential bioactive peptides derived from quinoa proteins have been identified. These proteins might be utilized as new ingredients in the development of functional foods or nutraceuticals with the aim of reducing oxidative stress-associated diseases, including cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Local e extensão da digestão em terneiros desmamados alimentados "Ad Libitum" com dietas ricas em concentrado contendo diferentes fontes de proteína suplementar Site and extent of digestion by weaned calves fed "Ad Libitum" on high concentrate-rich diets with different supplemental protein sources

Directory of Open Access Journals (Sweden)

Gilberto Vilmar Kozloski

1999-06-01

Full Text Available Foram utilizados nove terneiros da raça Holandesa (139 ± 2,4kg, fistulados no duodeno, em um delineamento experimental completamente casualizado para estudar o efeito da suplementação com diferentes fontes protéicas (2% de uréia ou 10% de farinha de carne na dieta total de dietas ricas em concentrado (milho e farelo de soja sobre o local e extensão da digestão do alimento, em condições de consumo ad libitum. A relação volumoso:concentrado das dietas foi de 30:70. A digestibilidade ruminal e total da matéria seca, matéria orgânica e nitrogênio, assim como o fluxo duodenal de nitrogênio microbiano e residual do alimento, e a eficiência da síntese protéica microbiana foram semelhantes nos dois tratamentos (P>0,10. A digestibilidade ruminal do amido também foi semelhante, mas a digestibilidade total foi menor no tratamento com uréia (PNine weaned Holstein calves (139 ± 2.4kg fitted with duodenal cannulas were used in a completly ramdomized design to study the effects of supplemental protein sources (2% of urea or 10% of meat meal of high concentrate diets (corn and soybean meal on site and extent of digestion of feed, in ad libitum feeding conditions. The forage:concentrate ratio was 30:70. The ruminal and total digestibility of dry matter, organic matter and nitrogen, as well as microbial and feed residual nitrogen duodenal flow, and the microbial protein synthesis efficiency were similar for both treatments (P>0.10. The ruminal digestibility of starch was also similar, but total digestibility was lower for urea treatment (P<0.10. However, this is probably due more to the limited capacity of ruminants to digest starch in the intestines than to an effect of the protein supplement. The use of urea or meat meal, as supplemental protein sources for corn and soybean meal based diets, formulated to supply the growth requirements of calves fed ad libitum, did not affect the digestion process.Thus, the choise of the protein

Metabolizable energy, nitrogen balance, and ileal digestibility of amino acids in quality protein maize for pigs

Science.gov (United States)

2014-01-01

Background To compare the nutritional value and digestibility of five quality protein maize (QPM) hybrids to that of white and yellow maize, two experiments were carried out in growing pigs. In experiment 1, the energy metabolizability and the nitrogen balance of growing pigs fed one of five QPM hybrid diets were compared against those of pigs fed white or yellow maize. In experiment 2, the apparent and standardized ileal digestibility (AID and SID, respectively) of proteins and amino acids from the five QPM hybrids were compared against those obtained from pigs fed white and yellow maize. In both experiments, the comparisons were conducted using contrasts. Results The dry matter and nitrogen intakes were higher in the pigs fed the QPM hybrids (P digestibility (P digestible lysine than normal maize. PMID:25045520

Digested disorder

Science.gov (United States)

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a new issue of reader’s digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28232877

Rapid and efficient protein enzymatic digestion: An experimental comparison

Czech Academy of Sciences Publication Activity Database

Dyčka, Filip; Bobáľ, P.; Mazanec, Karel; Bobálová, Janette

2012-01-01

Roč. 33, č. 2 (2012), s. 288-295 ISSN 0173-0835 R&D Projects: GA MŠk 1M0570; GA MŠk 1M06030; GA AV ČR IAA600040701 Institutional research plan: CEZ:AV0Z40310501 Keywords : in-gel digestion * MALDI - TOF MS * protein Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.261, year: 2012

Fiber digestion kinetics and protein degradability characteristics of stockpiled Tifton 85 bermudagrass.

Science.gov (United States)

Sechler, S R; Mullenix, M K; Holland, C M; Muntifering, R B

2017-09-01

A 2-yr study was conducted to determine effects of N fertilization level on fiber digestion kinetics and protein degradability characteristics of stockpiled Tifton 85 bermudagrass (T85). Six 0.76-ha pastures of stockpiled T85 were cut to a 10-cm stubble height on August 1 of each yr and fertilized with 56 (56N), 112 (112N), or 168 (168N) kg N/ha (2 pastures/treatment). Fiber digestion kinetics included the 72-hr potential extent of NDF digestion (PED), rate of NDF digestion, and lag time. In yr 1 and 2, PED decreased over the stockpile season. Rates of NDF digestion did not differ ( > 0.05) among N fertilization treatments in either yr. In yr 1, rate of NDF digestion was greatest ( digestion decreased ( digestion rates were similar for November and January 21 sampling dates. Lag time was greater ( digestion ( = -0.60 and -0.25 in yr 1 and 2, respectively) was observed. There was a trend ( = 0.06) for lignin concentration to be positively correlated with lag time ( = 0.39) in yr 1, and a strong relationship was observed in yr 2 ( = 0.91; digestion in stockpiled T85 were influenced more by temporal changes over the stockpile season than by N fertilization level. Supplement formulations based on kinetic parameters of fiber digestion may require periodic adjustment to insure that energy-yielding components of NDF are sufficient to meet animal requirements throughout the stockpile season. The CP fraction in stockpiled T85 contains sufficient RDP to support fibrolytic activity and growth of ruminal microorganisms throughout the stockpile season. Toward the latter end of the season, supplementation with sources of digestible fiber and RDP could be expected to increase MP supply to the host animal.

Digested disorder: Quarterly intrinsic disorder digest (April-May-June, 2013).

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a series of reader's digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Down scaled Kjeldahl digestion and flow injection conductometric system for determination of protein content in some traditional northern Thai foods.

Science.gov (United States)

Yanu, Pattama; Jakmunee, Jaroon

2017-09-01

A flow injection conductometric (FIC) system for determination of total Kjeldahl nitrogen (TKN) was developed for estimating total protein content in food. A small scale Kjeldahl digestion was performed with a short digestion time of only 20min. The digested solution was injected into the FIC system, and TKN was converted to ammonia gas in an alkaline donor stream of the system. The gas diffused through a membrane and dissolved into an acceptor stream causing an increase in conductivity as detected by a detector and recorded as a peak. Under the optimum condition, a linear calibration graph in the range of 4.00-100.00mgL -1 was obtained with LOD of 0.05mgL -1 . A good precision (0.04% RSD, n=11, 30.00mgNL -1 ) and high sample throughput of 72h -1 was achieved. The method was applied for determination of protein in some traditional northern Thai foods, revealing that they are good sources of proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

Amino acids digestibility of pelleted microparticle protein of fish meal and soybean meal in broiler chickens

Directory of Open Access Journals (Sweden)

N. Suthama

2018-05-01

Full Text Available Commom protein sources for poultry, fish meal and soybean meal, were ground to obtain reduced particle size. The particle was then dissolved in distilled water (1 : 4 w/v, and added with 2 mL virgin coconut oil for every 500 mL solution prior to ultrasound transducer (ultrasonic bath treatment to obtain protein microparticle. Reducing particle size is one possible way to increase protein utilization.180 birds were used for forced feeding and 10 other birds were plotted for endogenous correction, when they were one month and a half old. Microparticle protein of both ingredients were tested separately in either mash or pelleted forms and compared to intact protein. Completely randomized design with 3 treatments (intact, mash, and pellet and 6 replications (10 bidrs each was arranged for the respective ingredient. Protein and essential amino acid digestibilities, and calcium retention were the parameters measured. Analysis of variance continued to Duncan test were applied to statistically evaluate the data. Pelleted microparticle protein of fish meal and soybean meal, respectively, resulted in significantly (P<0.05 highest protein and amino acids digestibilities, and Ca retention although lower disgestibility of fewer amino acids was found in mash form. In conclusion, pelleted form of microparticle protein of either fish meal or soybean meal improve protein and mostly amino acids digestibilities, and calcium retention in broiler.

Thermoresponsive Arrays Patterned via Photoclick Chemistry: Smart MALDI Plate for Protein Digest Enrichment, Desalting, and Direct MS Analysis.

Science.gov (United States)

Meng, Xiao; Hu, Junjie; Chao, Zhicong; Liu, Ying; Ju, Huangxian; Cheng, Quan

2018-01-10

Sample desalting and concentration are crucial steps before matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) analysis. Current sample pretreatment approaches require tedious fabrication and operation procedures, which are unamenable to high-throughput analysis and also result in sample loss. Here, we report the development of a smart MALDI substrate for on-plate desalting, enrichment, and direct MS analysis of protein digests based on thermoresponsive, hydrophilic/hydrophobic transition of surface-grafted poly(N-isopropylacrylamide) (PNIPAM) microarrays. Superhydrophilic 1-thioglycerol microwells are first constructed on alkyne-silane-functionalized rough indium tin oxide substrates based on two sequential thiol-yne photoclick reactions, whereas the surrounding regions are modified with hydrophobic 1H,1H,2H,2H-perfluorodecanethiol. Surface-initiated atom-transfer radical polymerization is then triggered in microwells to form PNIPAM arrays, which facilitate sample loading and enrichment of protein digests by concentrating large-volume samples into small dots and achieving on-plate desalting through PNIPAM configuration change at elevated temperature. The smart MALDI plate shows high performance for mass spectrometric analysis of cytochrome c and neurotensin in the presence of 1 M urea and 100 mM NaHCO 3 , as well as improved detection sensitivity and high sequence coverage for α-casein and cytochrome c digests in femtomole range. The work presents a versatile sample pretreatment platform with great potential for proteomic research.

Digested disorder: Quarterly intrinsic disorder digest (July-August-September, 2013).

Science.gov (United States)

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a new issue of reader's digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Relationship between proportion and composition of albumins, and in vitro protein digestibility of raw and cooked pea seeds (Pisum sativum L.).

Science.gov (United States)

Park, Sei Joon; Kim, Tae Wan; Baik, Byung-Kee

2010-08-15

Peas provide an excellent plant protein resource for human diets, but their proteins are less readily digestible than animal proteins. To identify the relationship between composition and in vitro digestibility of pea protein, eight pea varieties with a wide range of protein content (157.3-272.7 g kg(-1)) were determined for the proportion of albumins and globulins, their compositions using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and in vitro protein digestibility (IVPD) before and after heat treatment using a multi-enzyme (trypsin, chymotrypsin and peptidase) method. The proportion of albumins based on total seed protein content decreased from 229 to 147 g kg(-1) as seed protein content increased from 157.3 to 272.7 g kg(-1), while the proportion of globulins increased from 483 to 590 g kg(-1). The IVPDs of eight raw pea seeds were 79.9-83.5%, with significant varietal variations, and those were improved to 85.9-86.8% by cooking. Albumins, including (pea albumins 2) PA2, trypsin inhibitor, lectin and lipoxygenase, were identified as proteolytic resistant proteins. Globulins were mostly digested by protease treatment after heating. The quantitative ratio of albumins and globulins, and the quantitative variations of albumin protein components, including lipoxygenase, PA2, lectins and trypsin inhibitors, appear to influence the protein digestibility of both raw and cooked pea seeds. Copyright (c) 2010 Society of Chemical Industry.

Digestion of isolated legume cells in a stomach-duodenum model: three mechanisms limit starch and protein hydrolysis.

Science.gov (United States)

Bhattarai, Rewati R; Dhital, Sushil; Wu, Peng; Chen, Xiao Dong; Gidley, Michael J

2017-07-19

Retention of intact plant cells to the end of the small intestine leads to transport of entrapped macronutrients such as starch and protein for colonic microbial fermentation, and is a promising mechanism to increase the content of resistant starch in diets. However, the effect of gastro-intestinal bio-mechanical processing on the intactness of plant cells and the subsequent resistance to enzymatic digestion of intracellular starch and protein are not well understood. In this study, intact cells isolated from legume cotyledons are digested in a laboratory model which mimics the mechanical and biochemical conditions of the rat stomach and duodenum. The resulting digesta are characterised in terms of cell (wall) integrity as well as intracellular starch and protein hydrolysis. The cells remained essentially intact in the model with negligible (ca. 2-3%) starch or protein digestion; however when the cells were mechanically broken and digested in the model, the hydrolysis was increased to 45-50% suggesting that intact cellular structures could survive the mixing regimes in the model stomach and duodenum sufficiently to prevent digestive enzyme access. Apart from intact cell walls providing effective barrier properties, they also limit digestibility by restricting starch gelatinisation during cooking, and significant non-specific binding of α-amylase is observed to both intact and broken cell wall components, providing a third mechanism hindering starch hydrolysis. The study suggests that the preservation of intactness of plant cells, such as from legumes, could be a viable approach to achieve the targeted delivery of resistant starch to the colon.

Prediction of crude protein digestibility of animal by-product meals for dogs by the protein solubility in pepsin method.

Science.gov (United States)

Kawauchi, Iris M; Sakomura, Nilva K; Pontieri, Cristiana F F; Rebelato, Aline; Putarov, Thaila C; Malheiros, Euclides B; Gomes, Márcia de O S; Castrillo, Carlos; Carciofi, Aulus C

2014-01-01

Animal by-product meals have large variability in crude protein (CP) content and digestibility. In vivo digestibility procedures are precise but laborious, and in vitro methods could be an alternative to evaluate and classify these ingredients. The present study reports prediction equations to estimate the CP digestibility of meat and bone meal (MBM) and poultry by-product meal (PM) using the protein solubility in pepsin method (PSP). Total tract CP digestibility of eight MBM and eight PM samples was determined in dogs by the substitution method. A basal diet was formulated for dog maintenance, and sixteen diets were produced by mixing 70 % of the basal diet and 30 % of each tested meal. Six dogs per diet were used to determine ingredient digestibility. In addition, PSP of the MBM and PM samples was determined using three pepsin concentrations: 0·02, 0·002 and 0·0002 %. The CP content of MBM and PM ranged from 39 to 46 % and 57 to 69 %, respectively, and their mean CP digestibility by dogs was 76 (2·4) and 85 (2·6) %, respectively. The pepsin concentration with higher Pearson correlation coefficients with the in vivo results were 0·0002 % for MBM (r 0·380; P = 0·008) and 0·02 % for PM (r 0·482; P = 0·005). The relationship between the in vivo and in vitro results was better explained by the following equations: CP digestibility of MBM = 61·7 + 0·2644 × PSP at 0·0002 % (P = 0·008; R (2) 0·126); and CP digestibility of PM = 54·1 + 0·3833 × PSP at 0·02 % (P = 0·005; R (2) 0·216). Although significant, the coefficients of determination were low, indicating that the models were weak and need to be used with caution.

A multi-laboratory evaluation of a common in vitro pepsin digestion assay protocol used in assessing the safety of novel proteins

NARCIS (Netherlands)

Thomas, K.; Aalbers, M.; Bannon, G. A.; Bartels, M.; Dearman, R. J.; Esdaile, D. J.; Fu, T. J.; Glatt, C. M.; Hadfield, N.; Hatzos, C.; Hefle, S. L.; Heylings, J. R.; Goodman, R. E.; Henry, B.; Herouet, C.; Holsapple, M.; Ladics, G. S.; Landry, T. D.; MacIntosh, S. C.; Rice, E. A.; Privalle, L. S.; Steiner, H. Y.; Teshima, R.; van Ree, R.; Woolhiser, M.; Zawodny, J.

2004-01-01

Rationale. Evaluation of the potential allergenicity of proteins derived from genetically modified foods has involved a weight of evidence approach that incorporates an evaluation of protein digestibility in pepsin. Currently, there is no standardized protocol to assess the digestibility of proteins

Quantitative assessment of in-solution digestion efficiency identifies optimal protocols for unbiased protein analysis

DEFF Research Database (Denmark)

Leon, Ileana R; Schwämmle, Veit; Jensen, Ole N

2013-01-01

a combination of qualitative and quantitative LC-MS/MS methods and statistical data analysis. In contrast to previous studies we employed both standard qualitative as well as data-independent quantitative workflows to systematically assess trypsin digestion efficiency and bias using mitochondrial protein...... conditions (buffer, RapiGest, deoxycholate, urea), and two methods for removal of detergents prior to analysis of peptides (acid precipitation or phase separation with ethyl acetate). Our data-independent quantitative LC-MS/MS workflow quantified over 3700 distinct peptides with 96% completeness between all...... protocols and replicates, with an average 40% protein sequence coverage and an average of 11 peptides identified per protein. Systematic quantitative and statistical analysis of physicochemical parameters demonstrated that deoxycholate-assisted in-solution digestion combined with phase transfer allows...

Discrimination of in vitro and in vivo digestion products of meat proteins from pork, beef, chicken, and fish.

Science.gov (United States)

Wen, Siying; Zhou, Guanghong; Song, Shangxin; Xu, Xinglian; Voglmeir, Josef; Liu, Li; Zhao, Fan; Li, Mengjie; Li, Li; Yu, Xiaobo; Bai, Yun; Li, Chunbao

2015-11-01

In vitro digestion products of proteins were compared among beef, pork, chicken, and fish. Gastric and jejunal contents from the rats fed these meat proteins were also compared. Cooked pork, beef, chicken, and fish were homogenized and incubated with pepsin alone or followed by trypsin. The digestion products with molecular weights of less than 3000 Da were identified with MALDI-TOF-MS and nano-LC-MS/MS. Gastric and jejunal contents obtained from the rats fed the four meat proteins for 7 days were also analyzed. After pepsin digestion, pork, and beef samples had a greater number of fragments in similarity than chicken and fish samples, but the in vitro digestibility was the greatest (p 0.05). A total of 822 and 659 peptides were identified from the in vitro and in vivo digestion products, respectively. Our results could interpret for the differences in physiological functions after the ingestion of different species of meat. © 2015 The Authors. PROTEOMICS Published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Psychrophilic anaerobic digestion of guinea pig manure in low-cost tubular digesters at high altitude.

Science.gov (United States)

Garfí, Marianna; Ferrer-Martí, Laia; Villegas, Vidal; Ferrer, Ivet

2011-05-01

Guinea pig is one of the most common livestock in rural communities of the Andes. The aim of this research was to study the anaerobic digestion of guinea pig manure in low-cost unheated tubular digesters at high altitude. To this end, the performance of two pilot digesters was monitored during 7 months; and two greenhouse designs were compared. In the dome roof digester the temperature and biogas production were significantly higher than in the shed roof digester. However, the biogas production rate was low (0.04 m(biogas)(3)m(digester)(-3) d(-1)), which is attributed to the low organic loading rate (0.6 kg(VS)m(digester)(-3)d(-1)) and temperature (23°C) of the system, among other factors. In a preliminary fertilization study, the potato yield per hectare was increased by 100% using the effluent as biofertilizer. Improving manure management techniques, increasing the organic loading rate and co digesting other substrates may be considered to enhance the process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Quantification of peptides released during in vitro digestion of cooked meat.

Science.gov (United States)

Sayd, T; Chambon, C; Santé-Lhoutellier, V

2016-04-15

We aimed to identify and quantify the peptides generated during in vitro digestion of cooked meat by liquid chromatography coupled with high resolution mass spectrometer. A total of 940 non-redundant peptides in the gastric compartment and 989 non-redundant peptides in the intestinal compartment were quantified and identified. Among the 71 different proteins identified, 43 meat proteins were found in the two digestive compartments, 20 proteins were specific to the gastric compartment and 8 proteins to the intestinal compartment. In terms of estimation, the proteins involved in muscle contraction and structure were preferentially enzymatically hydrolyzed in the small intestine. The effect of cooking provided different but less clear patterns of digestion. To the best of our knowledge, this constitutes the highest number of peptides identified in beef meat digests and provides a comprehensive database for meat protein digestion associated with cooking conditions. Such quantitative and qualitative differences may have important nutritional consequences. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of chemical composition and baking on in vitro digestibility of proteins in breads made from selected gluten-containing and gluten-free flours.

Science.gov (United States)

Wu, Tong; Taylor, Cheryl; Nebl, Thomas; Ng, Ken; Bennett, Louise E

2017-10-15

Breads prepared from cereal grains are a dietary staple, providing a significant proportion of daily energy, but not necessarily of dietary protein. However, good digestibility of proteins in bread is important to avoid potential immunogenic effects of undigested peptides, including for those gluten-intolerant. Four gluten-containing (white wheat, wholemeal wheat, spelt and rye) and four gluten-free (chick pea, lupin, buckwheat, amaranth) flours were used to make yeast-leavened breads standardized for protein. In vitro gastro-intestinal digestion of pre-mixes, doughs and breads baked for 20 and 35min was conducted followed by correlation analysis between fitted parameters of digestion profiles, chemical composition (protein, non-fibre carbohydrates, fibre, ash and total polyphenolics) and amino acid profiles. The results indicated that digestibility generally increased during proofing and decreased during baking. Relatively higher protein digestibility was correlated with ratio of non-fibre carbohydrate to protein and lower digestibility with increasing contents of fibre and total polyphenolics in pre-mixes. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Antioxidant properties of salmon (Salmo salar L.) protein fraction hydrolysates revealed following their ex vivo digestion and in vitro hydrolysis.

Science.gov (United States)

Borawska, Justyna; Darewicz, Małgorzata; Pliszka, Monika; Vegarud, Gerd E

2016-06-01

Salmon (Salmo salar L.) myofibryllar protein (MP) and sarcoplasmic protein (SP) were digested with human gastric and duodenal juices and hydrolysed in vitro with commercial pepsin and Corolase PP. The digestion after duodenal juice/Corolase PP caused almost complete breakdown of peptide bonds in MP and SP. The DPPH(•) scavenging activity of proteins decreased during both ex vivo digestion and in vitro hydrolysis. The highest value of DPPH(•) scavenging activity was shown for the gastric digest of SP (8.88 ± 0.87%). The ABTS(+•) scavenging activity of MP and SP increased during digestion/hydrolysis. The duodenal digest of SP was characterised by the highest value of ABTS(+•) scavenging activity (72.7 ± 1.2%). In turn, the highest value of ferric-reducing power was determined for the gastric digest of SP (84.8 ± 0.2%). Salmon antioxidant peptides Phe-Ile-Lys-Lys, His-Leu, Ile-Tyr, Pro-His-Leu, Pro-Trp, Val-Pro-Trp were identified in both ex vivo digested and in vitro hydrolysed MP and SP. An antioxidant peptide, Val-Tyr, was additionally detected in the in vitro hydrolysate of SP. The results indicate the salmon myofibrillar and sarcoplasmic protein fractions as potential sources of antioxidant peptides that could be released in the gastrointestinal tract but their amino acid sequence and quantification vary. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Chemical composition, true nutrient digestibility, and true metabolizable energy of novel pet food protein sources using the precision-fed cecectomized rooster assay.

Science.gov (United States)

Deng, P; Utterback, P L; Parsons, C M; Hancock, L; Swanson, K S

2016-08-01

A wide variety of animal protein-based ingredients is commonly used in the pet food products. The raw ingredients and processing procedures used may greatly affect protein quality. Testing the quality of alternative protein sources is necessary and contributes to the sustainability of pet foods. The objective of this study was to test the chemical composition of 8 protein sources intended for use in dog and cat foods (calamari meal, pork peptone, alligator meal, lamb meal, venison meal, chicken meal, and 2 duck meals), and evaluate their true nutrient digestibility and nitrogen-corrected true ME (TMEn) using the precision-fed cecectomized rooster assay. Calamari meal and pork peptone had lower ash (4.4 and 3.6% of DM, respectively) but greater CP (88.1 and 80.5% of DM, respectively) and either greater or similar GE (5.6 and 5.3 kcal/g of DM, respectively) compared with alligator, lamb, venison, chicken, and duck meals (11.8 to 24.5% ash, 58.7 to 65.9% CP, and 4.6 to 5.3 kcal GE/g). Acid-hydrolyzed fat (AHF) was lower in calamari meal (8.7% of DM) compared with the other proteins tested (15.5-22.1% of DM). True nutrient digestibility was variable among the protein sources (52 to 79% of DM, 60 to 83% of OM, 78 to 92% of AHF, and 70 to 89% of GE) with pork peptone having the highest DM, AHF, and GE digestibility and calamari meal having the highest OM digestibility. True indispensable AA digestibility was highest for calamari meal, with all AA having a digestibility greater than 90%. Except for histidine, all indispensable AA had a digestibility over 85% for pork peptone. In contrast, true indispensable AA digestibility was lowest for lamb meal, with histidine having digestibility less than 70% and the other entire indispensable AA having digestibility between 72 and 88%. The TMEn of calamari meal (4.82 kcal/g DM and 86.9% of GE) was greater ( digestibility among protein sources intended for use in dog and cat foods and justifies further in vivo testing of novel

Effect of Heating Method on Alteration of Protein Molecular Structure in Flaxseed: Relationship with Changes in Protein Subfraction Profile and Digestion in Dairy Cows.

Science.gov (United States)

Ahmad Khan, Nazir; Booker, Helen; Yu, Peiqiang

2015-02-04

This study evaluated the effect of heating methods on alteration of protein molecular structure in flaxseed (Linum usitatissimum L.) in relation to changes in protein subfraction profile and digestion in dairy cows. Seeds from two flaxseed varieties, sampled from two replicate plots at two locations, were evaluated. The seeds were either maintained in their raw state or heated in an air-draft oven (dry heating) or autoclave (moist heating) for 60 min at 120 °C or by microwave irradiation (MIR) for 5 min. Compared to raw seeds, moist heating decreased (P RUP) content (36.0 ± 5.19 to 46.9 ± 2.72% CP) and intestinal digestibility of RUP (61.0 ± 2.28 to 63.8 ± 2.67% RUP). Dry heating did not alter (P > 0.05) the protein subfraction profile and rumen degradation kinetics, whereas MIR increased (P RUP content from 36.0 ± 5.19 to 40.4 ± 4.67% CP. The MIR and dry heating did not alter (P > 0.05) the amide I to amide II ratio, but moist heating decreased (P RUP (R 2 = 0.71), and intestinal digestibility of RUP (R 2 = 0.72). Overall, heat-induced changes in protein nutritive value and digestion were strongly associated with heat-induced alteration in protein molecular structures.

Comparative ileal amino acid digestibility of distillers' grains for growing pigs.

Science.gov (United States)

Adeola, Olayiwola; Ragland, Darryl

2016-12-01

The objective of the experiment reported here was to investigate and compare the amino acid (AA) digestibility of distillers' dried grains (DDG), distillers' dried grains with solubles (DDGS), high protein distillers' dried grains (HP-DDG), and high protein distillers' dried grains with solubles (HP-DDGS) in growing pigs. Five semi-purified diets consisting of DDG, DDGS, HP-DDG, HP-DDGS, and nitrogen-free diet (NFD) were fed to pigs fitted with simple T-cannula for 5 observations per diet. Endogenous losses of AA at the terminal ileum of pigs that received the NFD were used to calculate standardized ileal digestibility (SID) of AA from apparent ileal digestibility (AID) of AA. The AID of Lys in DDGS was lower ( P  digestibility, there was no difference between DDG and DDGS in the SID of the indispensable AA. The SID of Lys in DDG was greater ( P  digestibility values for traditional and high-protein corn distillers' dried grains coproducts for use in formulating swine diets. Amino acid digestibility was generally higher in HP-DDG than in other tested co-products of the dry grind processing of corn for ethanol.

Capillary zone electrophoresis-multiple reaction monitoring from 100 pg of RAW 264.7 cell lysate digest.

Science.gov (United States)

Sun, Liangliang; Li, Yihan; Champion, Matthew M; Zhu, Guijie; Wojcik, Roza; Dovichi, Norman J

2013-06-07

Capillary zone electrophoresis-multiple/single reaction monitoring (CZE-MRM/SRM), which employed an electrokinetically driven sheath-flow electrospray interface, was used for the rapid and highly sensitive detection of protein analytes in complex tryptic digests. MRM channels were developed against a commercial exponential mixture of bovine proteins. Five proteins spanning four orders of magnitude concentration range were confidently detected from only 2.5 ng of the digest mixture; the mass detection limits (S/N = 3) of two detected proteins, alpha-casein and glutamate dehydrogenase were about 600 zmol and 30 amol, respectively. This technique was then applied to a RAW 264.7 cell lysate digest. Three proteins were confidently and reproducibly detected from 100 pg of this digest. The sample amount corresponds to the approximate protein content from a single cell, which suggests that CZE-MRM may be a useful analytical tool in chemical cytometry. In addition to providing highly sensitive detection of proteins in complex mixtures, this system is highly rapid; migration time of the protein digests was less than 10 min.

Processing traits and digestibility of extruded dog foods with soy protein concentrate.

Science.gov (United States)

Venturini, K S; Sarcinelli, M F; Baller, M A; Putarov, T C; Malheiros, E B; Carciofi, A C

2018-04-11

Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM-control diet based on poultry by-product meal (PBM); GM-a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%-diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%-diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. © 2018 Blackwell Verlag GmbH.

Effect of in vitro gastric and duodenal digestion on the allergenicity of grape lipid transfer protein

NARCIS (Netherlands)

Vassilopoulou, Emilia; Rigby, Neil; Moreno, F. Javier; Zuidmeer, Laurian; Akkerdaas, Jaap; Tassios, Ioannis; Papadopoulos, Nikos G.; Saxoni-Papageorgiou, Photini; van Ree, Ronald; Mills, Clare

2006-01-01

BACKGROUND: Severe grape allergy has been linked to lipid transfer protein (LTP) sensitization. LTPs are known to be resistant to pepsin digestion, although the effect of gastroduodenal digestion on its allergenicity has not been reported. OBJECTIVE: We sought to investigate the effect of gastric

Studies on voltammetric determination of cadmium in samples containing native and digested proteins

Energy Technology Data Exchange (ETDEWEB)

Drozd, Marcin; Pietrzak, Mariusz, E-mail: mariusz@ch.pw.edu.pl; Malinowska, Elżbieta

2014-03-01

Highlights: • Proteins exhibit diverse impact on the DPASV cadmium signals. • Proteins subjected to HNO{sub 3} introduce less interference, than the native ones. • Optimal amount of SDS depends on the kind of protein. • Presence of thiolated coating agents of QDs do not influence the analysis. - Abstract: This work focuses on determination of cadmium ions using anodic stripping voltammetry (ASV) on thin film mercury electrode in conditions corresponding to those obtained after digestion of cadmium-based quantum dots and their conjugates. It presents the impact of selected proteins, including potential receptors and surface blocking agents on the voltammetric determination of cadmium. Experiments regarding elimination of interferences related to proteins presence using sodium dodecyl sulfate (SDS) are also shown. Effect of SDS on selected analytical parameters and simplicity of analyses carried out was investigated in the framework of current studies. The significant differences of influence among tested proteins on ASV cadmium determination, as well as the variability in SDS effectiveness as the antifouling agent were observed and explained. This work is especially important for those, who design new bioassays and biosensors with a use of quantum dots as electrochemical labels, as it shows what problems may arise from presence of native and digested proteins in tested samples.

Enrichment of pasta with faba bean does not impact glycemic or insulin response but can enhance satiety feeling and digestive comfort when dried at very high temperature.

Science.gov (United States)

Greffeuille, Valérie; Marsset-Baglieri, Agnès; Molinari, Nicolas; Cassan, Denis; Sutra, Thibault; Avignon, Antoine; Micard, Valérie

2015-09-01

Enrichment of durum wheat pasta with legume flour enhances their protein and essential amino acid content, especially lysine content. However, despite its nutritional potential, the addition of a legume alters the rheological properties of pasta. High temperature drying of pasta reduces this negative effect by strengthening its protein network. The aim of our study was to determine if these changes in the pasta structure alter its in vitro carbohydrate digestibility, in vivo glycemic, insulin and satiety responses. We also investigated if high temperature drying of pasta can reduce the well-known digestive discomfort associated with the consumption of legume grains. Fifteen healthy volunteers consumed three test meals: durum wheat pasta dried at a low temperature (control), and pasta enriched with 35% faba bean dried at a low and at a very high temperature. When enriched with 35% legume flour, pasta maintained its nutritionally valuable low glycemic and insulin index, despite its weaker protein network. Drying 35% faba bean pasta at a high temperature strengthened its protein network, and decreased its in vitro carbohydrate digestion with no further decrease in its in vivo glycemic or insulin index. Drying pasta at a very high temperature reduced digestive discomfort and enhanced self-reported satiety, and was not associated with a modification of energy intake in the following meal.

Bioactivity of Cod and Chicken Protein Hydrolysates before and after in vitro Gastrointestinal Digestion

DEFF Research Database (Denmark)

Jamnik, Polona; Istenič, Katja; Wulff, Tune

2017-01-01

, where values of cod and chicken were (95.5±1.2) and (90.5±0.7) %, respectively. Neither species nor digestion had any effect on cellular metabolic energy. At proteome level, digested hydrolysates gave again significantly stronger responses than undigested counterparts; cod peptides here also gave...... somewhat stronger response than chicken peptides. The knowledge of the action of food protein hydrolysates and their digests within live cells, also at proteome level, is important for further validation of their activity in higher eukaryotes to develop new products, such as in this case chicken and cod...... muscle-derived peptides as functional ingredients....

The Protein Digestibility-Corrected Amino Acid Score (PDCAAS) - A concept for describing protein quality in foods and food ingredients: A critical review

NARCIS (Netherlands)

Schaafsma, G.

2005-01-01

Protein Digestibility-Corrected Amino Score (PDCAAS) is discussed. PDCAAS is now widely used as a routine assay for protein quality evaluation, replacing the more traditional biological methods [e.g., measurement of the Protein Efficiency Ratio (PER) in rats]. PDCAAS is based on comparison of the

Bacillus coagulans GBI-30, 6086 increases plant protein digestion in a dynamic, computer-controlled in vitro model of the small intestine (TIM-1).

Science.gov (United States)

Keller, D; Van Dinter, R; Cash, H; Farmer, S; Venema, K

2017-05-30

The aim of this study was to assess the potential of the probiotic Bacillus coagulans GBI-30, 6086 [GanedenBC 30 ] (BC30) to aid in protein digestion of alimentary plant proteins. To test this, three plant proteins, from pea, soy and rice, were digested in a validated in vitro model of the stomach and small intestine (TIM-1) in the absence and in the presence of BC30. Samples were taken from the TIM-1 fractions that mimic uptake of amino acids by the host and analysed for α-amino nitrogen (AAN) and total nitrogen (TN). Both were increased by BC30 for all three plant proteins sources. The ratio of TN/AAN indicated that for pea protein digestion was increased by BC30, but the degree of polymerisation of the liberated small peptides and free amino acids was not changed. For soy and rice, however, BC30 showed a 2-fold reduction in the TN/AAN ratio, indicating that the liberated digestion products formed during digestion in the presence of BC30 were shorter peptides and more free amino acids, than those liberated in the absence of BC30. As BC30 increased protein digestion and uptake in the upper gastrointestinal (GI) tract, it consequently also reduced the amount of protein that would be delivered to the colon, which could there be fermented into toxic metabolites by the gut microbiota. Thus, the enhanced protein digestion by BC30 showed a dual benefit: enhanced amino acid bioavailability from plant proteins in the upper GI tract, and a healthier environment in the colon.

Digested disorder, Quarterly intrinsic disorder digest (October-November-December, 2013).

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2015-01-01

This is the 4th issue of the Digested Disorder series that represents reader's digest of the scientific literature on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the fourth quarter of 2013; i.e. during the period of October, November, and December of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Experimental and clinical studies on simultaneous fat and protein tolerance digestion-absorption test using 131I-triolein and 125I-RISA

International Nuclear Information System (INIS)

Tokura, Yasunobu

1979-01-01

Simultaneous fat and protein tolerance digestion-absorption test using 131 I-triolein and 125 I-RISA was investigated experimentally in rats and clinically in 148 inpatients with various diseases. The results were as follows: Animal experiments. Fat absorption was markedly impaired in the exclusion of bile from the intestine. Each function of fat and protein absorption was independently detected. These animal experiments gave the clinical evaluation of this test for fat and protein digestion-absorption function. Clinical investigations. The test meal was prepared without using commercial Tween 80 as an emulgent. Either fat or protein absorption was markedly impaired in some patients with various diseases. Inpatients with various diseases investigated were divided into 3 groups by correlation coefficient between fecal excretion ratios of fat and protein. Each function of fat and protein digestion-absorption was able to be detected independently by this test simultaneously. This test can further be used as a labolatory aid in evaluating fat and protein digestion-absorption function in patients with malabsorption syndrome. (author)

Determination of antioxidant and chelating activity of protein hydrolysates from spirulina (Arthrospira maxima) obtained by simulated gastrointestinal digestion

OpenAIRE

Martínez-Palma, N.; Martínez-Ayala, A.; Dávila-Ortíz, G.

2015-01-01

Spirulina is a cyanobacteria that has been used as food since ancient times, for example in Mexico it was consumed by the Aztecs. Its high protein content, distribution and amino acid composition suggests the presence of important peptides encrypted within the sequences of parent proteins, that after been released by digestive process they could show an antioxidant effect. Our present study examined the above hypothesis through the determination of the antioxidant and chelating activity of tw...

Micro-scaled high-throughput digestion of plant tissue samples for multi-elemental analysis

Directory of Open Access Journals (Sweden)

Husted Søren

2009-09-01

Full Text Available Abstract Background Quantitative multi-elemental analysis by inductively coupled plasma (ICP spectrometry depends on a complete digestion of solid samples. However, fast and thorough sample digestion is a challenging analytical task which constitutes a bottleneck in modern multi-elemental analysis. Additional obstacles may be that sample quantities are limited and elemental concentrations low. In such cases, digestion in small volumes with minimum dilution and contamination is required in order to obtain high accuracy data. Results We have developed a micro-scaled microwave digestion procedure and optimized it for accurate elemental profiling of plant materials (1-20 mg dry weight. A commercially available 64-position rotor with 5 ml disposable glass vials, originally designed for microwave-based parallel organic synthesis, was used as a platform for the digestion. The novel micro-scaled method was successfully validated by the use of various certified reference materials (CRM with matrices rich in starch, lipid or protein. When the micro-scaled digestion procedure was applied on single rice grains or small batches of Arabidopsis seeds (1 mg, corresponding to approximately 50 seeds, the obtained elemental profiles closely matched those obtained by conventional analysis using digestion in large volume vessels. Accumulated elemental contents derived from separate analyses of rice grain fractions (aleurone, embryo and endosperm closely matched the total content obtained by analysis of the whole rice grain. Conclusion A high-throughput micro-scaled method has been developed which enables digestion of small quantities of plant samples for subsequent elemental profiling by ICP-spectrometry. The method constitutes a valuable tool for screening of mutants and transformants. In addition, the method facilitates studies of the distribution of essential trace elements between and within plant organs which is relevant for, e.g., breeding programmes aiming at

NUTRALYS® pea protein: characterization of in vitro gastric digestion and in vivo gastrointestinal peptide responses relevant to satiety

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Joost Overduin

2015-04-01

Design: Under in vitro simulated gastric conditions, the digestion of NUTRALYS® pea protein was compared to that of two dairy proteins, slow-digestible casein and fast-digestible whey. In vivo, blood glucose and gastrointestinal hormonal (insulin, ghrelin, cholecystokinin [CCK], glucagon-like peptide 1 [GLP-1], and peptide YY [PYY] responses were monitored in nine male Wistar rats following isocaloric (11 kcal meals containing 35 energy% of either NUTRALYS® pea protein, whey protein, or carbohydrate (non-protein. Results: In vitro, pea protein transiently aggregated into particles, whereas casein formed a more enduring protein network and whey protein remained dissolved. Pea-protein particle size ranged from 50 to 500 µm, well below the 2 mm threshold for gastric retention in humans. In vivo, pea-protein and whey-protein meals induced comparable responses for CCK, GLP-1, and PYY, that is, the anorexigenic hormones. Pea protein induced weaker initial, but equal 3-h integrated ghrelin and insulin responses than whey protein, possibly due to the slower gastric breakdown of pea protein observed in vitro. Two hours after meals, CCK levels were more elevated in the case of protein meals compared to that of non-protein meals. Conclusions: These results indicate that 1 pea protein transiently aggregates in the stomach and has an intermediately fast intestinal bioavailability in between that of whey and casein; 2 pea-protein- and dairy-protein-containing meals were comparably efficacious in triggering gastrointestinal satiety signals.

Effect of radiation processing on antinutrients, in-vitro protein digestibility and protein efficiency ratio bioassay of legume seeds

Energy Technology Data Exchange (ETDEWEB)

El-Niely, Hania F.G. [Food Irradiation Research Department, National Center for Radiation Research and Technology, Atomic Energy Authority, P.O. Box 29, Nasr City, Cairo (Egypt)]. E-mail: elniely@hotmail.com

2007-06-15

The effects of irradiation (dose levels of 5, 7.5 and 10 kGy) on nutritive characteristics of peas (Pisum satinum L), cowpeas (Vigna unguiculata L.Walp), lentils (Lens culinaris Med), kidneybeans (Phaseolus vulgaris L), and chickpeas (Cicer arietinum L) were examined. Analyses included proximate composition, levels of anti-nutrients (phytic acid, tannins), available lysine (AL), in vitro protein digestibility (IVPD), and protein efficiency ratio (PER) in the growing rat. The results showed that moisture, crude protein, crude fat, crude fiber, and ash were unchanged by the irradiation. Radiation processing significantly (p<0.05) reduced the levels of phytic acid (PA), tannins (TN), and AL. IVPD and PER were significantly enhanced in a dose-dependent manner, relative to unirradiated control samples, for all legumes. The data sets for each legume exhibited high correlation coefficients between radiation dose and PA, TN, AL, IVPD, and PER. These results demonstrate the benefits of irradiation on the nutritional properties of these legumes.

Effect of radiation processing on antinutrients, in-vitro protein digestibility and protein efficiency ratio bioassay of legume seeds

International Nuclear Information System (INIS)

El-Niely, Hania F.G.

2007-01-01

The effects of irradiation (dose levels of 5, 7.5 and 10 kGy) on nutritive characteristics of peas (Pisum satinum L), cowpeas (Vigna unguiculata L.Walp), lentils (Lens culinaris Med), kidneybeans (Phaseolus vulgaris L), and chickpeas (Cicer arietinum L) were examined. Analyses included proximate composition, levels of anti-nutrients (phytic acid, tannins), available lysine (AL), in vitro protein digestibility (IVPD), and protein efficiency ratio (PER) in the growing rat. The results showed that moisture, crude protein, crude fat, crude fiber, and ash were unchanged by the irradiation. Radiation processing significantly (p<0.05) reduced the levels of phytic acid (PA), tannins (TN), and AL. IVPD and PER were significantly enhanced in a dose-dependent manner, relative to unirradiated control samples, for all legumes. The data sets for each legume exhibited high correlation coefficients between radiation dose and PA, TN, AL, IVPD, and PER. These results demonstrate the benefits of irradiation on the nutritional properties of these legumes

Strategies in protein sequencing and characterization: Multi-enzyme digestion coupled with alternate CID/ETD tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Nardiello, Donatella; Palermo, Carmen, E-mail: carmen.palermo@unifg.it; Natale, Anna; Quinto, Maurizio; Centonze, Diego

2015-01-07

Highlights: • Multi-enzyme digestion for protein sequencing and characterization by CID/ETD. • Simultaneous use of trypsin/chymotrypsin for the maximization of sequence. • Identification of PTMs, sequence variants and species-specific residues. • Increase of accuracy in sequence assignments by orthogonal fragmentation techniques. - Abstract: A strategy based on a simultaneous multi-enzyme digestion coupled with electron transfer dissociation (ETD) and collision-induced dissociation (CID) was developed for protein sequencing and characterization, as a valid alternative platform in ion-trap based proteomics. The effect of different proteolytic procedures using chymotrypsin, trypsin, a combination of both, and Lys-C, was carefully evaluated in terms of number of identified peptides, protein coverage, and score distribution. A systematic comparison between CID and ETD is shown for the analysis of peptides originating from the in-solution digestion of standard caseins. The best results were achieved with a trypsin/chymotrypsin mix combined with CID and ETD operating in alternating mode. A post-database search validation of MS/MS dataset was performed, then, the matched peptides were cross checked by the evaluation of ion scores, rank, number of experimental product ions, and their relative abundances in the MS/MS spectrum. By integrated CID/ETD experiments, high quality-spectra have been obtained, thus allowing a confirmation of spectral information and an increase of accuracy in peptide sequence assignments. Overlapping peptides, produced throughout the proteins, reduce the ambiguity in mapping modifications between natural variants and animal species, and allow the characterization of post translational modifications. The advantages of using the enzymatic mix trypsin/chymotrypsin were confirmed by the nanoLC and CID/ETD tandem mass spectrometry of goat milk proteins, previously separated by two-dimensional gel electrophoresis.

SIMULATING PROTEIN DIGESTION ON TROUT A RAPID AND INEXPENSIVE METHOD FOR DOCUMENTING FISH MEAL QUALITY AND SCREENING NOVEL PROTEIN SOURCES FOR USE IN AQUAFEEDS

Directory of Open Access Journals (Sweden)

M Bassompierre

1997-10-01

Full Text Available A novel in vitro digestion system, which simulated rainbow trout gastric and intestinal digestion was developed. The method was employed to evaluate the impact of the gastric phase of digestion upon degradation of three fish meals od differing quality. Results illustrated that two-phase gastric-intestinal digestion increased the discriminatory powers of the system when compared to one-step intestinal digestion. A comparison of the system with pH-STAT methods demonstrated that the in vitro technique was superior. The presented method provides an ethical and cost effective means for rapid evaluation of fish meals and potentially, alternative protein sources for aquafeeds.

High-solids anaerobic co-digestion of sewage sludge and food waste in comparison with mono digestions: stability and performance.

Science.gov (United States)

Dai, Xiaohu; Duan, Nina; Dong, Bin; Dai, Lingling

2013-02-01

System stability and performance of high-solids anaerobic co-digestion of dewatered sludge (DS) and food waste (FW) in comparison with mono digestions were investigated. System stability was improved in co-digestion systems with co-substrate acting as a diluting agent to toxic chemicals like ammonia or Na(+). For high-solids digestion of DS, the addition of FW not only improved system stability but also greatly enhanced volumetric biogas production. For high-solids digestion of FW, the addition of DS could reduce Na(+) concentration and help maintain satisfactory stability during the conversion of FW into biogas. System performances of co-digestion systems were mainly determined by the mixing ratios of DS and FW. Biogas production and volatile solids (VSs) reduction in digestion of the co-mixture of DS and FW increased linearly with higher ratios of FW. A kinetic model, which aimed to forecast the performance of co-digestion and to assist reactor design, was developed from long-term semi-continuous experiments. Maximum VS reduction for DS and FW was estimated to be 44.3% and 90.3%, respectively, and first order constant k was found to be 0.17d(-1) and 0.50 d(-1), respectively. Experimental data of co-digestion were in good conformity to the predictions of the model. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ingestion of Casein in a Milk Matrix Modulates Dietary Protein Digestion and Absorption Kinetics but Does Not Modulate Postprandial Muscle Protein Synthesis in Older Men.

Science.gov (United States)

Churchward-Venne, Tyler A; Snijders, Tim; Linkens, Armand M A; Hamer, Henrike M; van Kranenburg, Janneau; van Loon, Luc J C

2015-07-01

The slow digestion and amino acid absorption kinetics of isolated micellar casein have been held responsible for its relatively lower postprandial muscle protein synthetic response compared with rapidly digested proteins such as isolated whey. However, casein is normally consumed within a milk matrix. We hypothesized that protein digestion and absorption kinetics and the subsequent muscle protein synthetic response after micellar casein ingestion are modulated by the milk matrix. The aim of this study was to determine the impact of a milk matrix on casein protein digestion and absorption kinetics and postprandial muscle protein synthesis in older men. In a parallel-group design, 32 healthy older men (aged 71 ± 1 y) received a primed continuous infusion of L-[ring-(2)H5]-phenylalanine, L-[ring-3,5-(2)H2]-tyrosine, and L-[1-(13)C]-leucine, and ingested 25 g intrinsically L-[1-(13)C]-phenylalanine and L-[1-(13)C]-leucine labeled casein dissolved in bovine milk serum (Cas+Serum) or water (Cas). Plasma samples and muscle biopsies were collected in the postabsorptive state and for 300 min in the postprandial period to examine whole-body and skeletal muscle protein metabolism. Casein ingestion increased plasma leucine and phenylalanine concentrations and L-[1-(13)C]-phenylalanine enrichments, with a more rapid rise after Cas vs. Cas+Serum. Nonetheless, dietary protein-derived phenylalanine availability did not differ between Cas+Serum (47 ± 2%, mean ± SEM) and Cas (46 ± 3%) when assessed over the 300-min postprandial period (P = 0.80). The milk matrix did not modulate postprandial myofibrillar protein synthesis rates from 0 to 120 min (0.038 ± 0.005 vs. 0.031 ± 0.007%/h) or from 120 to 300 min (0.052 ± 0.004 vs. 0.067 ± 0.005%/h) after Cas+Serum vs. Cas. Similarly, no treatment differences in muscle protein-bound L-[1-(13)C]-phenylalanine enrichments were observed at 120 min (0.003 ± 0.001 vs. 0.002 ± 0.001) or 300 min (0.015 ± 0.002 vs. 0.016 ± 0.002 mole

Buffalo Cheese Whey Proteins, Identification of a 24 kDa Protein and Characterization of Their Hydrolysates: In Vitro Gastrointestinal Digestion.

Science.gov (United States)

Bassan, Juliana C; Goulart, Antonio J; Nasser, Ana L M; Bezerra, Thaís M S; Garrido, Saulo S; Rustiguel, Cynthia B; Guimarães, Luis H S; Monti, Rubens

2015-01-01

Milk whey proteins are well known for their high biological value and versatile functional properties, characteristics that allow its wide use in the food and pharmaceutical industries. In this work, a 24 kDa protein from buffalo cheese whey was analyzed by mass spectrometry and presented homology with Bos taurus beta-lactoglobulin. In addition, the proteins present in buffalo cheese whey were hydrolyzed with pepsin and with different combinations of trypsin, chymotrypsin and carboxypeptidase-A. When the TNBS method was used the obtained hydrolysates presented DH of 55 and 62% for H1 and H2, respectively. Otherwise for the OPA method the DH was 27 and 43% for H1 and H2, respectively. The total antioxidant activities of the H1 and H2 samples with and without previous enzymatic hydrolysis, determined by DPPH using diphenyl-p-picrylhydrazyl radical, was 4.9 and 12 mM of Trolox equivalents (TE) for H2 and H2Dint, respectively. The increased concentrations for H1 and H2 samples were approximately 99% and 75%, respectively. The in vitro gastrointestinal digestion efficiency for the samples that were first hydrolyzed was higher compared with samples not submitted to previous hydrolysis. After in vitro gastrointestinal digestion, several amino acids were released in higher concentrations, and most of which were essential amino acids. These results suggest that buffalo cheese whey is a better source of bioavailable amino acids than bovine cheese whey.

Nutritional value and digestion rate of rhea meat proteins in association with storage and cooking processes.

Science.gov (United States)

Filgueras, Renata S; Gatellier, Philippe; Ferreira, Claude; Zambiazi, Rui C; Santé-Lhoutellier, Véronique

2011-09-01

The nutritional value of proteins was investigated after the storage and cooking of rhea M. Gastrocnemius pars interna. Oxidation of basic and aromatic amino acids, surface hydrophobicity and aggregation state of proteins, were determined in raw and cooked meat. In addition, myofibrillar proteins were exposed in vitro to proteases of the digestive tract. Cooking markedly affected the protein surface hydrophobicity. The BBP bound content was three times greater in cooked than in fresh rhea meat. A small increment in tryptophan content after cooking was observed. Storage influenced Schiff bases formation indicating the presence of protein-aldehyde adducts after cooking. High content of Schiff bases was found after cooking of samples stored for 5 days, demonstrating a probable implication of free amino groups, most likely from lysine. Cooking decreased the myofibrillar protein susceptibility to pepsin activity. After cooking, the proteolysis rate by pancreatic enzymes increased. Our findings support the importance of protein aggregation in the nutritional value of meat proteins. Copyright © 2011 Elsevier Ltd. All rights reserved.

Intermediate-Scale High-Solids Anaerobic Digestion System Operational Development

Energy Technology Data Exchange (ETDEWEB)

Rivard, C. J.

1995-02-01

Anaerobic bioconversion of solid organic wastes represents a disposal option in which two useful products may be produced, including a medium Btu fuel gas (biogas) and a compost-quality organic residue. The application of high-solids technology may offer several advantages over conventional low-solids digester technology. The National Renewable Energy Laboratory (NREL) has developed a unique digester system capable of uniformly mixing high-solids materials at low cost. During the first 1.5 years of operation, a variety of modifications and improvements were instituted to increase the safety, reliability, and performance of the system. Those improvements, which may be critical in further scale-up efforts using ,the NREL high-solids digester design are detailed in this report.

Minor milk constituents are affected by protein concentration and forage digestibility in the feed ration

DEFF Research Database (Denmark)

Larsen, Torben; Alstrup, Lene; Weisbjerg, Martin Riis

2016-01-01

The present study was conducted in order to investigate if selected minor milk components would be indicative for the nutritional situation of the cow. Forty-eight dairy cows were offered a high digestible ration vs. a lower digestible ration combined with 2 protein levels in a 4 × 4 Latin square...... design. Milk glucose, glucose-6-phosphate, cholesterol, triacylglycerides (TAG), uric acid and β-hydroxybutyrate (BHBA) were measured and correlated mutually and towards other milking parameters (yield, h since last milking, days in milk (DIM), urea, etc). The variation range of the suggested variables...... were broad, a fact that may support their utilisation as predictive parameters. The content of milk metabolites was significantly affected by the change in rations as milk glucose, glucose-6-phosphate, uric acid, and the ratio cholesterol: triacylglycerides increased with higher energy intake while...

D-tagatose has low small intestinal digestibility but high large intestinal fermentability in pigs.

Science.gov (United States)

Laerke, H N; Jensen, B B

1999-05-01

The digestibility of D-tagatose, its effect on the digestibility of macronutrients and the metabolic response of the microbiota of the gastrointestinal tract to the ingestion of this carbohydrate were studied in pigs. Eight pigs were fed a low fiber diet comprising 15% sucrose (control group). Another eight pigs were fed a similar diet except that 100 g sucrose per kg diet was replaced by D-tagatose (test group). After 18 d, the pigs were killed and the gastrointestinal contents removed for analysis. The digestibility of D-tagatose was 25.8 +/- 5.6% in the distal third of the small intestine. The small intestinal digestibilities of dry matter (86.9 +/- 1.3 vs. 92.9 +/- 0.9%), gross energy (74.4 +/- 1.6 vs. 80.7 +/- 1.8%) and sucrose (90.4 +/- 2.5 vs. 98.0 +/- 0.5%) were lower (P D-tagatose. Digestibilities of starch, protein and fat did not differ between groups. D-Tagatose, sucrose and starch were fully digested in the large intestine. The fecal digestibilities of energy, dry matter and fat did not differ between the two groups, whereas D-tagatose reduced the fecal digestibility of protein (91.1 +/- 0.6 vs. 93.5 +/- 0.7%, P D-Tagatose served as a substrate for the microbiota in the cecum and proximal colon as indicated by a reduced pH, and a greater ATP concentration, adenylate energy charge (AEC) ratio and concentration of short-chain fatty acids. In particular, the increase in the concentrations of propionate, butyrate and valerate suggests possible health benefits of this monosaccharide.

Reg proteins and their roles in inflammation and cancer of the human digestive system.

Science.gov (United States)

Zhao, Jie; Wang, Jingyu; Wang, Hao; Lai, Maode

2013-01-01

The regenerating gene (Reg) family is a group of small molecules that includes four members found in various species, although only three are found in human tissues. Their expression is stimulated by certain growth factors or cytokines. The Reg family plays different roles in proliferation, migration, and anti-apoptosis through activating different signaling pathways. Their dysexpression is closely associated with a number of human conditions and diseases such as inflammation and cancer, especially in the human digestive system. Clinically, upregulation of Reg proteins is usually demonstrated in histological sections and sera from cancer patients. Therefore, Reg proteins can predict the progression and prognosis of cancers, especially those of the digestive tract, and can also act as diagnostic markers and therapeutic targets.

Protein digestibility and ammonia excretion in catfish Clarias gariepinus culture

Directory of Open Access Journals (Sweden)

Bambang Gunadi

2014-01-01

Full Text Available ABSTRACT A series of experiments was performed to analyze protein digestibility, ammonia excretion, and also heterothropic bacteria and phytoplankton dynamics in the catfish Clarias gariepinus culture. In the digestibility experiment, catfish with an individual initial size of 43.67±0.83 g were stocked into 120 L conical fiberglass tanks at a density of 20 fish per tank. Fish were fed on with commercial diet supplemented with Cr2O3 indicator at a concentration of 1%. In the ammonia excretion experiment, catfish with an individual size of 111.6±9.5 and 40.6±3.4 g, respectively,  were placed into a 10 L chamber filled with 8 L of water. Total ammonia nitrogen (TAN in the chambers were monitored every hour for six consecutive hours. In the bacteria and phytoplankton dynamics experiment, catfish were stocked in the 25 m2 concrete tanks which was divided into two compartments (catfish 10 m2, and heterotrof compartments 15 m2. Catfish with individual size of 42,5±0 g were stocked into the tanks at a density of 100 fish per tank. Water was recirculated from catfish compartments to heterotrophic compartments. Fish were fed with floating feed. Molasses as carbon source for heterotrophic bacteria was applied daily. The experiment was conducted for six weeks. The results showed that the protein digestibility was 61.97±7.24%. Larger fish (size of 111.6 g excreted ammonia at a rate of 0.008±0.003 mg TAN/g fish-weight/hour, which was lower than that of the smaller catfish (size of 40.6 g, i.e. 0.012±0.004 mg TAN/g fish-weight/hour. Keywords: protein digestibility, ammonia excretion, catfish  ABSTRAK Serangkaian penelitian telah dilakukan untuk menganalisis ketercernaan pakan dan protein, ekskresi amonia, serta dinamika bakteri dan fitoplankton pada budidaya ikan lele (Clarias gariepinus. Pada penelitian ketercernaan pakan, ikan lele berukuran 43,67±0,83 g/ekor dipelihara dalam bak fiberglas berbentuk corong berukuran 120 L dengan kepadatan 20

Quantification of the main digestive processes in ruminants: the equations involved in the renewed energy and protein feed evaluation systems.

Science.gov (United States)

Sauvant, D; Nozière, P

2016-05-01

The evolution of feeding systems for ruminants towards evaluation of diets in terms of multiple responses requires the updating of the calculation of nutrient supply to the animals to make it more accurate on aggregated units (feed unit, or UF, for energy and protein digestible in the intestine, or PDI, for metabolizable protein) and to allow prediction of absorbed nutrients. The present update of the French system is based on the building and interpretation through meta-analysis of large databases on digestion and nutrition of ruminants. Equations involved in the calculation of UF and PDI have been updated, allowing: (1) prediction of the out flow rate of particles and liquid depending on the level of intake and the proportion of concentrate, and the use of this in the calculation of ruminal digestion of protein and starch from in situ data; (2) the system to take into account the effects of the main factors of digestive interactions (level of intake, proportion of concentrate, rumen protein balance) on organic matter digestibility, energy losses in methane and in urine; (3) more accurate calculation of the energy available in the rumen and the efficiency of its use for the microbial protein synthesis. In this renewed model UF and PDI values of feedstuffs vary depending on diet composition, and intake level. Consequently, standard feed table values can be considered as being only indicative. It is thus possible to predict the nutrient supply on a wider range of diets more accurately and in particular to better integrate energy×protein interactions occurring in the gut.

In vitro crude protein digestibility of Tenebrio molitor and Hermetia illucens insect meals and its correlation with chemical composition traits

Directory of Open Access Journals (Sweden)

Stefania Marono

2015-07-01

Full Text Available The aims of this study were to evaluate the correlation between in vitro crude protein digestibility coefficients of insect meals from Tenebrio molitor (TI and Hermetia illucens (HI and their chemical composition traits as well as to develop regression equations able to estimate the in vitro crude protein digestibility (CPd from proximate analysis of insect meals. Twelve samples of insect meals (6 from TM larvae, TM 1-6 and 6 from HI larvae, HI 1-6 were obtained from different producers and analysed for chemical composition and in vitro crude protein digestibility by a two-step enzymatic method (digestion with pepsin and trypsin-enriched pancreatin. For both insect meal samples, CPd was negatively correlated to ADF and chitin contents, while just for HI there was a positive correlation (P<0.01 between CP percentage of the samples and CPd. For both insect meals the former variable chosen in the stepwise analysis was the chitin, explaining the 79.45% of CPd variability for Tenebrio molitor samples and the 98.30% for Hermetia illucens. In the second step, the amount of protein linked to ADF was added in the model for T. molitor and CP for H. illucens samples. The coefficients chitin is the main constituent of insect body able to affect the crude protein digestibility of Tenebrio molitor and Hermetia illucens larvae meals estimated by an in vitro enzymatic method.

Microbial Insight into a Pilot-Scale Enhanced Two-Stage High-Solid Anaerobic Digestion System Treating Waste Activated Sludge.

Science.gov (United States)

Wu, Jing; Cao, Zhiping; Hu, Yuying; Wang, Xiaolu; Wang, Guangqi; Zuo, Jiane; Wang, Kaijun; Qian, Yi

2017-11-30

High solid anaerobic digestion (HSAD) is a rapidly developed anaerobic digestion technique for treating municipal sludge, and has been widely used in Europe and Asia. Recently, the enhanced HSAD process with thermal treatment showed its advantages in both methane production and VS reduction. However, the understanding of the microbial community is still poor. This study investigated microbial communities in a pilot enhanced two-stage HSAD system that degraded waste activated sludge at 9% solid content. The system employed process "thermal pre-treatment (TPT) at 70 °C, thermophilic anaerobic digestion (TAD), and mesophilic anaerobic digestion (MAD)". Hydrogenotrophic methanogens Methanothermobacter spp. dominated the system with relative abundance up to about 100% in both TAD and MAD. Syntrophic acetate oxidation (SAO) bacteria were discovered in TAD, and they converted acetate into H₂ and CO₂ to support hydrogenotrophic methanogenesis. The microbial composition and conversion route of this system are derived from the high solid content and protein content in raw sludge, as well as the operational conditions. This study could facilitate the understanding of the enhanced HSAD process, and is of academic and industrial importance.

Apparent or Standardized Ileal Digestibility of Amino Acids of Diets Containing Different Protein Feedstuffs Fed at Two Crude Protein Levels for Growing Pigs

Directory of Open Access Journals (Sweden)

A. O. Adebiyi

2015-09-01

Full Text Available The current study determined the apparent or standardized ileal digestibility of amino acids (AID or SID of AA in growing pigs fed diets containing three protein feedstuffs with different fiber characteristics at two dietary crude protein (CP levels. Twenty boars (Yorkshire×Landrace with average initial body weight of 35 (±2.6 kg were fitted with a simple T-cannula at the distal ileum. These pigs were offered six diets containing soybean meal (SBM, canola meal (CM or corn distillers dried grains with solubles (corn-DDGS that were either adequate (19% or marginal (15% in CP using a triplicated 6×2 Youden Square Design. Except for Met, Trp, Cys, and Pro, AID of AA was greater (p<0.05 in the SBM diet compared with the CM diet. Apparent ileal digestibility for Gly and Asp was greater (p<0.05 in the SBM diet compared with the corn-DDGS diet. The AID of Ile, Leu, Phe, Val, Ala, Tyr, and Asp was greater (p<0.05 in the corn-DDGS diet compared with the CM diet. Standardized ileal digestibility of AA was greater (p<0.05 in the SBM diet compared with the CM diet for all AA except Trp and Pro. The SID of Ile, Leu, Val, Ala, Tyr, and Asp was greater (p<0.05 in the corn-DDGS diet compared with the CM diet. It was concluded that protein feedstuff affects ileal AA digestibility and is closely related to dietary fiber characteristics, and a 4-percentage unit reduction in dietary CP had no effect on ileal AA digestibility in growing pigs.

Phytase studies in pigs and poultry: effect on protein digestion and energy utilization

NARCIS (Netherlands)

Kies, A.K.

2005-01-01

Phytase is applied for improving digestibility of phosphorus in pig and poultry diets. Indepen-dently, phytase also improves animal performance. The mechanisms to explain this effect were investigated and quantified. Protein can be complexed with phytate, especially under the acid conditions that

Deep shaft high rate aerobic digestion: laboratory and pilot plant performance

Energy Technology Data Exchange (ETDEWEB)

Tran, F; Gannon, D

1981-01-01

The Deep Shaft is essentially an air-lift reactor, sunk deep in the ground (100-160 m); the resulting high hydrostatic pressure together with very efficient mixing in the shaft provide extremely high O transfer efficiencies (O.T.E.) of less than or equal to 90% vs. 4-20% in other aerators. This high O.T.E. suggests real potential for Deep-Shaft technology in the aerobic digestion of sludges and animal wastes: with conventional aerobic digesters an O.T.E. over 8% is extremely difficult to achieve. Laboratory and pilot plant Deep-Shaft aerobic digester studies carried out at Eco-Research's Pointe Claire, Quebec laboratories, and at the Paris, Ontario pilot Deep-Shaft digester are described.

Effect of non-protein nitrogen and fodder legumes on the intake, digestibility and growth parameters of buffaloes

International Nuclear Information System (INIS)

Premaratne, S.

1990-01-01

Two in vivo digestibility studies and three nylon bag studies were conducted using four rumen fistulated male buffaloes to investigate the role of supplements of tree legumes and non-protein nitrogen on the feed intake, rumen function and growth of buffaloes given a basal diet of rice straw. Straw dry matter (DM) intake and digestibility were increased by urea treatment compared with urea supplementation. Inclusion of legume tree leaves in the diet increased the in vivo DM digestibility of both untreated and treated straw, but the increment was much higher for untreated straw. A supplementation of legumes also increased the in vivo nitrogen (N) digestibility of the diet of buffaloes. A trend towards an increase in straw intake with legume supplementation was also observed. Of the tree fodder legumes tested, Erythrina lithosperma had the highest potential for providing protein. Inclusion of legumes in the diet increased the DM and N degradation rates of feedstuff. In a growth trial of grazing female buffalo calves, the inclusion of fodder legumes increased the weight gain when compared with grazing alone. (author). 6 refs, 5 tabs

Dietary Considerations in Autism Spectrum Disorders: The Potential Role of Protein Digestion and Microbial Putrefaction in the Gut-Brain Axis.

Science.gov (United States)

Sanctuary, Megan R; Kain, Jennifer N; Angkustsiri, Kathleen; German, J Bruce

2018-01-01

Children with autism spectrum disorders (ASD), characterized by a range of behavioral abnormalities and social deficits, display high incidence of gastrointestinal (GI) co-morbidities including chronic constipation and diarrhea. Research is now increasingly able to characterize the "fragile gut" in these children and understand the role that impairment of specific GI functions plays in the GI symptoms associated with ASD. This mechanistic understanding is extending to the interactions between diet and ASD, including food structure and protein digestive capacity in exacerbating autistic symptoms. Children with ASD and gut co-morbidities exhibit low digestive enzyme activity, impaired gut barrier integrity and the presence of antibodies specific for dietary proteins in the peripheral circulation. These findings support the hypothesis that entry of dietary peptides from the gut lumen into the vasculature are associated with an aberrant immune response. Furthermore, a subset of children with ASD exhibit high concentrations of metabolites originating from microbial activity on proteinaceous substrates. Taken together, the combination of specific protein intakes poor digestion, gut barrier integrity, microbiota composition and function all on a background of ASD represents a phenotypic pattern. A potential consequence of this pattern of conditions is that the fragile gut of some children with ASD is at risk for GI symptoms that may be amenable to improvement with specific dietary changes. There is growing evidence that shows an association between gut dysfunction and dysbiosis and ASD symptoms. It is therefore urgent to perform more experimental and clinical research on the "fragile gut" in children with ASD in order to move toward advancements in clinical practice. Identifying those factors that are of clinical value will provide an evidence-based path to individual management and targeted solutions; from real time sensing to the design of diets with personalized

The Effects of Different Energy and Protein Ratio to Sheep’s Nutrient Intake and Digestibility

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Sri Mawati

2013-06-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The objective of this research was to study the effects of different energy and protein ratio towards sheep’s nutrient intake and digestibility. Twenty four male sheep’s, 6 – 7 months old with initial average live weight 13+1.56 kg, coefficient variant11.78% were used in this research. The complete feed ration which consisted of King Grass (Pennisetum purpureum, soybean powder, rice bran, dried cassava and molasses was used in this research. Protein content on each component was 10, 12 and 14% and total digestible nutrients (TDN 60 and 65%, respectively. Dry matter (DM and organic matter (OM intake, DM and OM digestibility were studied in this research. Analysis of variance (ANOVA was employed to analyze the data. Test of Small Difference (P<0.05 was then carried out if significant different occurred. The research results showed that Dry matter and OM ration intake showed significant different among treatments (P<0.05. The highest DM intake was obtained at crude protein (CP 14% and TDN 65% i.e. 695.54 g while the lowest value was CP 14% and TDN 65% i.e. 462.11 g. Thus different DM and OM intake were caused by different ration ingredients composition. Dry matter and OM ration digestibility were not show

Antigenic stability of pecan [Carya illinoinensis (Wangenh.) K. Koch] proteins: effects of thermal treatments and in vitro digestion.

Science.gov (United States)

Venkatachalam, Mahesh; Teuber, Suzanne S; Peterson, W Rich; Roux, Kenneth H; Sathe, Shridhar K

2006-02-22

Rabbit polyclonal antibody-based inhibition ELISA as well as immunoblotting analyses of proteins extracted from variously processed pecans (cv. Desirable) indicate that pecan proteins are antigenically stable. Pecan antigens were more sensitive to moist heat than dry heat processing treatments. SDS-PAGE and immunoblotting analysis of the native and heat-denatured proteins that were previously subjected to in vitro simulated gastric fluid digestions indicate that stable antigenic peptides were produced. Both enzyme-to-substrate ratio and digestion time were influential in determining the stability of pecan polypeptides. The stable antigenic polypeptides may serve as useful markers in developing assays suitable for the detection of trace amounts of pecans in foods.

Effect of thymol and carvacrol on nutrient digestibility in rams fed high or low concentrate diets.

Science.gov (United States)

Zamiri, M J; Azizabadi, E; Momeni, Z; Rezvani, M R; Atashi, H; Akhlaghi, A

2015-01-01

Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (Pdigestibility. The main effect of carvacrol on ruminal ammonia levels and NB was significant, but within each level of dietary concentrate no significant differences were observed in ammonia levels and NB. Inclusion of 0.3 g/kg diet DM of carvacrol or thyme was more effective than 0.6 g/kg diet DM in terms of NB but neither dose affected nutrient digestibility. Future research should determine the long-term effects of essential oils on digestibility and performance in sheep, before recommendation can be made for their use under practical husbandry conditions.

Effects of diets containing vegetable protein concentrates on performance and activity of digestive enzymes in silver catfish (Rhamdia quelen

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Naglezi de Menezes Lovatto

2014-02-01

Full Text Available The purpose of study was to evaluate the effect of using protein concentrates crambe and sunflower meal in the diet of silver catfish juveniles, as substitute for animal protein source. A total of 300 silver catfish had been separate in 15 experimental units of 280 L, totaling five treatments with three replications. We evaluated two levels (25% and 50% replacement of the meat and bone meal by protein concentrates of crambe and sunflower meals. Evaluated growth parameters, biological index and digestive enzymes in fish. There was no statistical difference for mass (g and standard length (cm, but the fish diet CPFCr-25% had greater total length (cm. No difference in dry matter, crude protein and total protein deposited (calculated. However, there was a higher concentration of ash in the carcass of the animals fed the control diet and CPFCr-50% in relation to diet CPFG- 50%, in addition, higher levels of lipids in fish fed diet CPFG-50%. No significant differences for hepatosomatic index, digestive somatic index and intestinal quotient of animals subjected to different treatments. The activity of digestive enzymes trypsin and chymotrypsin did not change. There was increased activity of acid protease. The quantitative and qualitative increase in protein concentration from this fraction allows the use of bran protein concentrates crambe and sunflower as substitutes for animal protein source.

Personalizing Protein Nourishment

Science.gov (United States)

DALLAS, DAVID C.; SANCTUARY, MEGAN R.; QU, YUNYAO; KHAJAVI, SHABNAM HAGHIGHAT; VAN ZANDT, ALEXANDRIA E.; DYANDRA, MELISSA; FRESE, STEVEN A.; BARILE, DANIELA; GERMAN, J. BRUCE

2016-01-01

Proteins are not equally digestible—their proteolytic susceptibility varies by their source and processing method. Incomplete digestion increases colonic microbial protein fermentation (putrefaction), which produces toxic metabolites that can induce inflammation in vitro and have been associated with inflammation in vivo. Individual humans differ in protein digestive capacity based on phenotypes, particularly disease states. To avoid putrefaction-induced intestinal inflammation, protein sources and processing methods must be tailored to the consumer’s digestive capacity. This review explores how food processing techniques alter protein digestibility and examines how physiological conditions alter digestive capacity. Possible solutions to improving digestive function or matching low digestive capacity with more digestible protein sources are explored. Beyond the ileal digestibility measurements of protein digestibility, less invasive, quicker and cheaper techniques for monitoring the extent of protein digestion and fermentation are needed to personalize protein nourishment. Biomarkers of protein digestive capacity and efficiency can be identified with the toolsets of peptidomics, metabolomics, microbial sequencing and multiplexed protein analysis of fecal and urine samples. By monitoring individual protein digestive function, the protein component of diets can be tailored via protein source and processing selection to match individual needs to minimize colonic putrefaction and, thus, optimize gut health. PMID:26713355

imFASP: An integrated approach combining in-situ filter-aided sample pretreatment with microwave-assisted protein digestion for fast and efficient proteome sample preparation.

Science.gov (United States)

Zhao, Qun; Fang, Fei; Wu, Ci; Wu, Qi; Liang, Yu; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

2016-03-17

An integrated sample preparation method, termed "imFASP", which combined in-situ filter-aided sample pretreatment and microwave-assisted trypsin digestion, was developed for preparation of microgram and even nanogram amounts of complex protein samples with high efficiency in 1 h. For imFASP method, proteins dissolved in 8 M urea were loaded onto a filter device with molecular weight cut off (MWCO) as 10 kDa, followed by in-situ protein preconcentration, denaturation, reduction, alkylation, and microwave-assisted tryptic digestion. Compared with traditional in-solution sample preparation method, imFASP method generated more protein and peptide identifications (IDs) from preparation of 45 μg Escherichia coli protein sample due to the higher efficiency, and the sample preparation throughput was significantly improved by 14 times (1 h vs. 15 h). More importantly, when the starting amounts of E. coli cell lysate decreased to nanogram level (50-500 ng), the protein and peptide identified by imFASP method were improved at least 30% and 44%, compared with traditional in-solution preparation method, suggesting dramatically higher peptide recovery of imFASP method for trace amounts of complex proteome samples. All these results demonstrate that the imFASP method developed here is of high potential for high efficient and high throughput preparation of trace amounts of complex proteome samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

International Nuclear Information System (INIS)

Bayr, S.; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-01-01

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was unstable in mono-digestion. • Free NH 3 inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH 4 -N and/or free NH 3 ) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m 3 d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm 3 /kg VS fed . On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm 3 /kg VS fed ). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials

Effects of macro-nutrient, micro-nutrient composition and cooking conditions on in vitro digestibility of meat and aquatic dietary proteins.

Science.gov (United States)

Luo, Jiaqiang; Taylor, Cheryl; Nebl, Thomas; Ng, Ken; Bennett, Louise E

2018-07-15

Animal and aquatic meats represent important sources of dietary protein and micro-nutrients. Although red and processed meats carry some risks for human health, sensory and nutritional advantages drive meat consumption. Therefore, it is important to understand how meat processing and cooking influence healthiness. The research aim was to investigate relationships of meat composition (proximates, amino acids and minerals) and cooking conditions (raw, 90 s microwave, 200 °C oven for 10 or 30 min) on protein digestibility, for a selection of four animal (beef, chicken, pork, kangaroo) and four aquatic meats (salmon, trout, prawn, oyster). Lean meats were minced before cooking followed by in vitro gastro-intestinal digestion and analysed for progress of hydrolysis, and size ranges of peptides using MALDI-TOF-MS. Correlation matrix analysis between compositional and functional parameters indicated that digestibility was significantly linked with protein and metal concentrations, likely reflecting moisture-dependent solubility and inter-mixing of sarcoplasmic metallo-proteins and insoluble myofibrillar proteins. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Anaerobic co-digestion of pig manure and algae: impact of intracellular algal products recovery on co-digestion performance.

Science.gov (United States)

Astals, S; Musenze, R S; Bai, X; Tannock, S; Tait, S; Pratt, S; Jensen, P D

2015-04-01

This paper investigates anaerobic co-digestion of pig manure and algae (Scenedesmus sp.) with and without extraction of intracellular algal co-products, with views towards the development of a biorefinery concept for lipid, protein and/or biogas production. Protein and/or lipids were extracted from Scenedesmus sp. using free nitrous acid pre-treatments and solvent-based Soxhlet extraction, respectively. Processing increased algae methane yield between 29% and 37% compared to raw algae (VS basis), but reduced the amount of algae available for digestion. Co-digestion experiments showed a synergy between pig manure and raw algae that increased raw algae methane yield from 0.163 to 0.245 m(3) CH4 kg(-1)VS. No such synergy was observed when algal residues were co-digested with pig manure. Finally, experimental results were used to develop a high-level concept for an integrated biorefinery processing pig manure and onsite cultivated algae, evaluating methane production and co-product recovery per mass of pig manure entering the refinery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Intestinal digestibility of amino acids in rumen undegradable protein estimated using a precision-fed cecectomized rooster bioassay: I. Soybean meal and SoyPlus.

Science.gov (United States)

Boucher, S E; Calsamiglia, S; Parsons, C M; Stein, H H; Stern, M D; Erickson, P S; Utterback, P L; Schwab, C G

2009-09-01

The objectives of this experiment were to measure intestinal digestibility of AA in rumen undegradable protein (RUP-AA) in soybean meal (SBM) and expeller SBM (SoyPlus, West Central, Ralston, IA; SP) and to determine if these feeds contain a constant protein fraction that is undegradable in the rumen and indigestible in the small intestine, as assumed in the French Institut National de la Recherche Agronomique (Paris, France) and Scandinavian AAT-PBV (AAT = AA absorbed from small intestine; PBV = protein balance in the rumen) models. Three samples of SBM and 3 samples of SP were obtained from the Feed Analysis Consortium Inc. (Savoy, IL). To obtain the RUP fraction, samples were ruminally incubated in situ for 16 h in 4 lactating cows, and the collected rumen undegraded residues (RUR) were pooled by sample. Subsamples of the intact feeds and RUR were crop intubated to 4 cecectomized roosters, and total excreta were collected for 48 h. Intact feeds, RUR, and excreta were analyzed for AA. Basal endogenous AA loss estimates were obtained from fasted birds and were used to calculate standardized digestibility of AA in the intact feeds and RUP-AA. Indigestibility coefficients of the intact feeds were calculated as (100 - % standardized AA digestibility), and indigestibility of the RUR was calculated as [(100 - % ruminal degradation of AA) x [(100 - % standardized RUP-AA digestibility)]/100]. Results indicated that standardized digestibility of feed-AA was similar to standardized digestibility of RUP-AA for SBM and SP samples and that standardized digestibility of individual AA differed within samples. Standardized feed-AA and RUP-AA digestibility values were lowest for Lys and Cys and highest for Trp and Met. Results also indicated that SBM and SP did not contain a constant protein fraction that was both undegradable in the rumen and indigestible in the small intestine. Indigestibility values of RUR were lower than in intact feeds, suggesting that SBM and SP contain a

Effect of heat and homogenization on in vitro digestion of milk.

Science.gov (United States)

Tunick, Michael H; Ren, Daxi X; Van Hekken, Diane L; Bonnaillie, Laetitia; Paul, Moushumi; Kwoczak, Raymond; Tomasula, Peggy M

2016-06-01

Central to commercial fluid milk processing is the use of high temperature, short time (HTST) pasteurization to ensure the safety and quality of milk, and homogenization to prevent creaming of fat-containing milk. Ultra-high-temperature sterilization is also applied to milk and is typically used to extend the shelf life of refrigerated, specialty milk products or to provide shelf-stable milk. The structures of the milk proteins and lipids are affected by processing but little information is available on the effects of the individual processes or sequences of processes on digestibility. In this study, raw whole milk was subjected to homogenization, HTST pasteurization, and homogenization followed by HTST or UHT processing. Raw skim milk was subjected to the same heating regimens. In vitro gastrointestinal digestion using a fasting model was then used to detect the processing-induced changes in the proteins and lipids. Using sodium dodecyl sulfate-PAGE, gastric pepsin digestion of the milk samples showed rapid elimination of the casein and α-lactalbumin bands, persistence of the β-lactoglobulin bands, and appearance of casein and whey peptide bands. The bands for β-lactoglobulin were eliminated within the first 15min of intestinal pancreatin digestion. The remaining proteins and peptides of raw, HTST, and UHT skim samples were digested rapidly within the first 15min of intestinal digestion, but intestinal digestion of raw and HTST pasteurized whole milk showed some persistence of the peptides throughout digestion. The availability of more lipid droplets upon homogenization, with greater surface area available for interaction with the peptides, led to persistence of the smaller peptide bands and thus slower intestinal digestion when followed by HTST pasteurization but not by UHT processing, in which the denatured proteins may be more accessible to the digestive enzymes. Homogenization and heat processing also affected the ζ-potential and free fatty acid release

Níveis de proteína e de arginina digestível na ração pré-inicial de frangos de corte Protein and digestible arginine levels in pre-starter broiler rations

Directory of Open Access Journals (Sweden)

Mônica Schaitl Thon

2010-05-01

Full Text Available O experimento foi conduzido para avaliar níveis de proteína bruta e arginina digestível na ração pré-inicial de frangos de corte e seus efeitos no desempenho das aves dos 7 aos 21 dias de idade. Foram utilizados 600 pintos da linhagem Cobb 500, distribuídos em delineamento de blocos casualizados em esquema fatorial 4 × 2, composto de quatro níveis de arginina digestível (1,363; 1,463; 1,563 e 1,663% e dois níveis de proteína bruta (20 e 22%, totalizando oito tratamentos, cada um com cinco repetições de 15 aves. Avaliaram-se o ganho de peso, o consumo de ração, o índice de conversão alimentar, a biometria dos órgãos do trato gastrintestinal e a digestibilidade e retenção de matéria seca e nitrogênio. O maior ganho de peso na fase de 1 a 14 dias de idade foi obtido com a ração com 22% de proteína bruta. Os níveis de arginina digestível tiveram efeito quadrático na conversão alimentar na fase de 1 a 10 dias de idade. O peso do esôfago e inglúvio foi maior nas aves alimentadas com a ração com 20% de proteína bruta, no entanto, houve efeito quadrático dos níveis de arginina digestível sobre o comprimento do intestino aos 10 dias de idade e sobre o peso do esôfago + inglúvio aos 3 dias de idade. Houve interação entre os níveis de proteína bruta e arginina digestível para o peso relativo do fígado aos 14 dias, que respondeu de forma quadrática ao nível de 20% de proteína bruta, e para o comprimento de intestino, cujo maior valor foi obtido com os níveis de 22% de proteína bruta e 1,603% de arginina digestível. O balanço e a retenção de nitrogênio foram maiores no nível de 22% de proteína bruta. O nível de 1,363% de arginina digestível atende às exigências nutricionais dos frangos de corte na fase pré-inicial.This experiment was carried out to evaluate levels of crude protein and digestible arginine in pre-starter broiler ration and their effects on the performance of the broilers from 7 to

Identification of protein binders in works of art by high-performance liquid chromatography-diode array detector analysis of their tryptic digests.

Science.gov (United States)

Fremout, Wim; Sanyova, Jana; Saverwyns, Steven; Vandenabeele, Peter; Moens, Luc

2009-04-01

Proteins in works of art are generally determined by the relative amounts of amino acids. This method, however, implies a loss of information on the protein structure and its modifications. Consequently, we propose a method based on the analysis of trypsin digests using high-performance liquid chromatography (HPLC) UV diode array detection (DAD) for painting binder studies. All reaction steps are done in the same vial; no extraction methods or sample transfer is needed, reducing the risk of sample losses. A collection of pure binders (collagen, ovalbumin, yolk and casein) as well as homemade and historical paint samples have been investigated with this method. Chromatograms of unknowns at 214 nm and 280 nm are compared with those of the reference samples as a fingerprint. There is a good agreement between many peptides, but others seem to have been lost or their retention time shifted due to small compositional changes because of ageing and degradation of the paint. The results are comparable with the results of other techniques used for binder identification on the same samples, with the additional advantage of differentiation between egg yolk and glair.

In Vitro Pepsin Digestibility of Cooked Proso Millet ( Pancium miliaceum L.) and Related Species from Around the World.

Science.gov (United States)

Gulati, Paridhi; Jia, Shangang; Li, Aixia; Holding, David Richard; Santra, Dipak; Rose, Devin Jerrold

2018-06-20

Thirty-three accessions of proso millet (Panicum miliaceum) with different countries of origin were screened for their pepsin digestibility after cooking to identify samples with high digestibility. The pepsin digestibility of all samples ranged from 26 to 57% (average 32%). There were no apparent differences in protein profiles (SDS-PAGE) of samples with the lowest, intermediate, and highest digestibilities. However, LC-MS/MS analysis revealed a negative correlation between pepsin digestibility and peptides that matched to high molecular weight proteins (24 kDa) from Panicum hallii with regions of contiguous hydrophobic amino acids. Low digestibility upon cooking was also observed for other species from the Panicum genus, such as little millet, switchgrass and panicgrass, which suggests a unique inherent property of the genus. The obtained results from this study may form a basis for in-depth analysis of proso proteins that may help in developing new cultivars with higher digestibility upon cooking.

An assessment of differences in the ruminal degradability and intestinal digestibility of crude protein in brewer’s grains and maize draff

Directory of Open Access Journals (Sweden)

Vladimír Majer

2012-01-01

Full Text Available The submitted thesis aims to assess the differences between the ruminal degradability and intestinal digestibility of crude protein contained in brewer’s grains (BG and maize draff (AMG. The effectiveness of ruminal degradability was tested using the “in sacco” method on 3 dry Holstain cows fitted with rumen cannulas. The dynamics of ruminal degradability of crude protein (CP was detected after 0, 4, 8, 16, and 24 hours of samples incubation in the rumen. The intestinal digestibility of crude protein undegradable in the rumen was determined using the “mobile bag” method on 3 dry Holstain cows fitted with duodenal cannulas. The crude protein degradability of BG was detected in the above-mentioned hours (%: 4.06; 18.16; 32.40; 38.56, and 50.70; crude protein degradability of AMG: 42.04; 63.56; 84.47; 85.16, and 87.19. The effectiveness of rumen degradability of BG crude protein at the rate of passage of rumen content 6 % per hour was calculated at 35.33 % and that of AMG, at 76.29 %. Intestinal digestibility of BG crude protein and dry matter at the rate of passage of intestinal content 6 % per hour was calculated at 79.41 % and 22.84 %, respectively, and that of AMG, at 57.01 % and 11.33 %, respectively. The differences between the indicators of both feedstuffs were significant (P < 0.05. The results show that BG are mostly a source of crude protein with higher intestinal digestibility than AMG.

Milk production response to varying protein supply is independent of forage digestibility in dairy cows

DEFF Research Database (Denmark)

Alstrup, Lene; Weisbjerg, Martin Riis; Hymøller, Lone

2014-01-01

rations: (1) high digestibility and high CP concentration (HdHp), (2) high digestibility and low CP concentration (HdLp), (3) low digestibility and high CP concentration (LdHp), and (4) low digestibility and low CP concentration (LdLp). All rations contained 30% corn silage, 25% grass-clover silage...... of the same concentrate per day in the automatic milking system in addition to the mixed ration. Every feeding period lasted 3 wk, and DM intake and milk yield were measured in the last week in each period, and milk samples for determining milk composition, including fatty acid content, and blood samples were...... taken during the last 3d of each period. Dry matter intake increased by 2.2 kg/d on Hd compared with Ld and by 0.7 kg/d on Hp compared with Lp. The positive effect on DM intake was reflected in the energy-corrected milk (ECM) yield, as a higher ration digestibility increased the ECM yield by 1.7 kg...

Effects of ruminal protein degradability and frequency of supplementation on site and extent of digestion and ruminal fermentation characteristics in lambs fed low-quality forage.

Science.gov (United States)

Atkinson, R L; Toone, C D; Ludden, P A

2010-02-01

Four ruminally and duodenally cannulated Suffolk wether lambs (34.5 +/- 2.0 kg initial BW) were used in a 4 x 4 Latin square-designed experiment to examine the effects of ruminal protein degradability and supplementation frequency on site and extent of digestion in lambs consuming a low-quality forage diet. Wethers were fed a basal diet of mature crested wheatgrass hay (4.2% CP) for ad libitum consumption plus 1 of 4 supplements: 1) a high RDP supplement provided daily (RDP-D), 2) the high RDP supplement provided on alternate days (RDP-A), 3) a high RUP supplement provided on alternate days (RUP-A), or 4) a 50:50 mixture of the RDP and RUP supplements, provided on alternate days (MIX-A). Forage OM, N, NDF, or ADF intakes were not affected by treatment. True ruminal OM digestibility was greater (P RUP-A lambs compared with other treatments. Ruminal digestibilities of NDF and ADF were greater (P RUP had less (P RUP-A lambs exhibiting the least concentrations and least variation over time. Ruminal urease activity was not affected by treatment. Microbial N flow was not affected by treatment; however, there was an increase (P = 0.004) in microbial efficiency for RDP-D lambs. Alternate day protein supplementation with a mixture of RDP and RUP may improve digestibility in lambs consuming low-quality forage, which may be related to decreased fluctuation in ruminal ammonia concentrations as a result of greater endogenous N recycling.

Protein enrichment, cellulase production and in vitro digestion improvement of pangolagrass with solid state fermentation.

Science.gov (United States)

Hu, Chan-Chin; Liu, Li-Yun; Yang, Shang-Shyng

2012-02-01

Pangolagrass, Digitaria decumbens Stent, is a major grass for cow feeding, and may be a good substrate for protein enrichment. To improve the quality of pangolagrass for animal feeding, cellulolytic microbes were isolated from various sources and cultivated with solid state fermentation to enhance the protein content, cellulase production and in vitro digestion. The microbes, culture conditions and culture media were studied. Cellulolytic microbes were isolated from pangolagrass and its extracts, and composts. Pangolagrass supplemented with nitrogen and minerals was used to cultivate the cellulolytic microbes with solid state fermentation. The optimal conditions for protein enrichment and cellulase activity were pangolagrass substrate at initial moisture 65-70%, initial pH 6.0-8.0, supplementation with 2.5% (NH(4))(2)SO(4), 2.5% KH(2)PO(4) and K(2)HPO(4) mixture (2:1, w/w) and 0.3% MgSO(4).7H(2)O and cultivated at 30(o)C for 6 days. The protein content of fermented pangolagrass increased from 5.97-6.28% to 7.09-16.96% and the in vitro digestion improved from 4.11-4.38% to 6.08-19.89% with the inoculation of cellulolytic microbes by solid state fermentation. Each 1 g of dried substrate yielded Avicelase 0.93-3.76 U, carboxymethylcellulase 1.39-4.98 U and β-glucosidase 1.20-6.01 U. The isolate Myceliophthora lutea CL3 was the strain found to be the best at improving the quality of pangolagrass for animal feeding with solid state fermentation. Solid state fermentation of pangolagrass inoculated with appropriate microbes is a feasible process to enrich protein content, increase in vitro digestibility and improve the quality for animal feeding. Copyright © 2011. Published by Elsevier B.V.

Extraction, partial characterization and evaluation of in vitro digestibility of the protein associated with the exoskeleton of white shrimp (Litopenaeus vannamei

Directory of Open Access Journals (Sweden)

Escobedo-Lozano, A.Y.

2014-01-01

Full Text Available The need of new food sources to satisfy human requirements forces researchers to study any possible alternative supplies. Therefore this study aimed to explore the quality and digestibility evaluation of the protein fractions obtained as a by-product of processing the shrimp exoskeleton Litopenaeus vannamei. Shrimp exoskeletons were washed, they were dried, mincedand they were brought under acid hydrolysis and alkaline hydrolysis; released proteins were then precipitated and characterized. 496 g of demineralized exoskeleton were obtained from 1 kg of shrimp shell; out of these, 376 g corresponded to chitin and 120 g corresponded to protein Total protein content was 33.80 ± 0.34 %. The digestible protein fractions were 26.7 g and 92.1 g were insoluble proteins. Of this latter fraction, the largest proportion belonged to the scleroprotein type. The amino acid profile analysis from the recovered proteins indicated that there were present nine amino acids out of the ten essential ones, being leucine the one with the highest proportion. In vitro digestibility was shown to be up to an 83.7 %. Therefore, it was possible to conclude that the recovery of digestibleproteins from shrimp exoskeleton may be useful in diet formulation.

Reducing dietary protein in pond production of hybrid striped bass - study shows a significant reduction is possible in digestible protein level in commercial diets

Science.gov (United States)

In previous work, we demonstrated that diets containing 40% digestible protein (DP) (45% crude protein) and 18 %lipid supplemented with Met and Lys resulted in superior performance and nutrient retentions in hybrid striped bass compared to less energy-dense diets when rearing hybrid striped bass at ...

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

Energy Technology Data Exchange (ETDEWEB)

Bayr, S., E-mail: suvi.bayr@jyu.fi; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-10-15

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was unstable in mono-digestion. • Free NH{sub 3} inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH{sub 4}-N and/or free NH{sub 3}) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m{sup 3} d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm{sup 3}/kg VS{sub fed}. On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm{sup 3}/kg VS{sub fed}). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials.

Effects of a concentrate of pea antinutritional factors on pea protein digestibility in piglets

NARCIS (Netherlands)

Guen, M.P. Le; Huisman, J.; Guéguen, J.; Beelen, G.; Verstegen, M.W.A.

1995-01-01

Four experiments were designed to investigate the apparent ileal digestibility of raw pea (Pisum sativum) and two of its components - an isolate of its proteins and a concentrate of its proteinaceous antinutritional factors (ANFs). Three varieties of peas were used: spring varieties Finale and

Dietary protein reduction on microbial protein, amino acids digestibility, and body retention in beef cattle. I. Digestibility sites and ruminal synthesis estimated by purine bases and 15N as markers.

Science.gov (United States)

Mariz, Lays Débora Silva; Amaral, Paloma de Melo; Valadares Filho, Sebastião de Campos; Santos, Stefanie Alvarenga; Marcondes, Marcos Inácio; Prados, Laura Franco; Carneiro Pacheco, Marcos Vinícius; Zanetti, Diego; de Castro Menezes, Gustavo Chamon; Faciola, Antonio P

2018-06-04

The objectives of this study were to evaluate the effect of reducing dietary CP contents on 1) total and partial nutrient digestion and nitrogen balance and 2) on microbial crude protein (MCP) synthesis and true MCP digestibility in the small intestine obtained with 15N and purine bases (PB) in beef cattle. Eight bulls (4 Nellore and 4 Crossbred Angus × Nellore) cannulated in the rumen and ileum were distributed in duplicated 4 × 4 Latin squares. The diets consisted of increasing CP contents: 100, 120, or 140 g CP/kg DM offered ad libitum, and restricted intake (RI) diet with 120 g CP/kg DM. The experiment lasted four 17-d periods, with 10 d for adaptation to diets and another 7 for data collection. Omasal digesta flow was obtained using Co-EDTA and indigestible NDF (iNDF) as markers, and to estimate ileal digesta flow only iNDF was used. From days 11 to 17 of each experimental period, ruminal infusions of Co-EDTA (5.0 g/d) and 15N (7.03 g of ammonium sulfate enriched with 10% of 15N atoms) were performed. There was no effect of CP contents (linear effect, P = 0.55 and quadratic effect, P = 0.11) on ruminal OM digestibility. Intake of CP linearly increased (P content (P ruminally degradable OM and true ruminally degradable OM) had a quadratic tendency (P = 0.07 and P = 0.08, respectively) to CP increasing and was numerically greatest at 120 g CP/kg DM. The adjusted equations for estimating true intestinal digestibility of MCP (Y1) and total CP (Y2) were, respectively, as follows: Y1 =--16.724(SEM = 40.06) + 0.86X(SEM = 0.05) and Y2 = -43.81(SEM = 49.19) + 0.75X(SEM = 0.05). It was concluded that diets with 120 g/kg of CP optimize the microbial synthesis and efficiency and ruminal ash and protein NDF digestibility, resulting in a better use of N compounds in the rumen. The PB technique can be used as an alternative to the 15N to estimate microbial synthesis.

Effect of substrates and intermediate compounds on foaming in manure digestion systems

DEFF Research Database (Denmark)

Boe, Kanokwan; Kougias, Panagiotis; Pacheco, F.

2012-01-01

Manure contains several compounds that can potentially cause foaming during anaerobic digestion. Understanding the effect of substrates and intermediate compounds on foaming tendency and stability could facilitate strategies for foaming prevention and recovery of the process. In this study...... potential to create foam in a manure digester. Moreover, high organic loading of lipids and protein, and high concentrations of acetic and butyric acids also showed a strong tendency to create foaming during anaerobic digestion. Due to their great ability to stabilize foam, high organic loadings of Na...

Digestibility marker and ileal amino acid digestibility in phytase-supplemented soybean or canola meals for growing pigs.

Science.gov (United States)

Favero, A; Ragland, D; Vieira, S L; Owusu-Asiedu, A; Adeola, O

2014-12-01

Two experiments using soybean meal (SBM) or canola meal (CM) were conducted to investigate whether the choice of digestibility marker influenced the apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of N and AA in diets supplemented with phytase. In each experiment, 18 barrows fitted with T-cannulas at the ileocecal junction were assigned to 3 diets consisting of a N-free diet to determine endogenous losses of N and AA, a semipurified diet (SBM in Exp. 1 or CM in Exp. 2), and the semipurified diet supplemented with phytase at 1,000 phytase units/kg. Three digestibility markers including acid-insoluble ash (AIA), chromic oxide (Cr2O3), and titanium dioxide (TiO2) were added to each diet at 3 g/kg. Each diet was fed for 7 d, consisting of a 5-d adjustment and a 2-d collection of ileal digesta. In both studies, basal ileal endogenous losses determined with Cr2O3 as a digestibility marker were lower (Pdigestibility markers. Using SBM as the protein source in Exp. 1, there was no interaction between phytase and digestibility marker on AID or SID of AA. The AID of N and AA in SBM using AIA as a digestibility marker tended to be lower (Pdigestibility markers. Phytase supplementation increased (Pdigestibility marker tended to be associated with lower (Pdigestibility marker and phytase. Phytase supplementation had effects (Pdigestibility marker. With Cr2O3 or TiO2 as the digestibility marker in the CM diets, phytase supplementation increased (Pdigestibility marker. In contrast, there were no clear improvements in AA digestibility from phytase supplementation for SBM. Phytase effects on AID or SID of AA were dependent on the digestibility marker used in diets when CM was used as the protein source but not when SBM was used as the protein source. Therefore, AA digestibility response to phytase supplementation may depend on the protein being evaluated as well as the choice of digestibility marker.

Digestibility and nitrogen balance of diets containing non conventional vegetable proteins fed to pigs of genetic strains suitable for outdoor systems

Directory of Open Access Journals (Sweden)

L. Sardi

2010-04-01

Full Text Available The study was carried out to evaluate on growing pigs kept in metabolism crates, either belonging to a “traditional” cross-breed (Duroc x Large White – DLW or a local breed (Cinta Senese – CS, the digestibility and the nitrogen balance of non-conventional vegetable protein sources (field beans, pea and sunflower cake when compared to soybean meal. The four diets were formulated so as to supply the same crude protein amount. CS pigs showed lower apparent digestibility coefficients (ADCs for crude protein (81,38% vs 82,65% and crude fibre (35,97% vs 40,65%. Nitrogen balance was more favourable in DLW pigs (32,12% vs 19,67% which showed a higher nitrogen retention (+69%.With respect to the protein source, no differences were observed for nitrogen balance. Sunflower diet showed the higher ADC for ether extract (+20% compared with soybean diet. Crude fibre digestibility was lowered in sunflower (-33% and field beans (-13% diets. Sunflower and field beans diets showed the lowest gross energy digestibility coefficients. Field pea diet had the highest ADC for crude fibre (+ 12% leading to ADCs for organic matter and gross energy comparable to those of soybean meal. It is concluded that field bean, sunflower cake and field pea could be considered as valuable non-conventional protein sources in swine nutrition.

Influence of Non-fibrous Carbohydrate and Degradable Intake protein and Ruminal Fermentation ,Nutrien Digestion and performance of Local Sheep

Directory of Open Access Journals (Sweden)

Efka AR

2001-05-01

Full Text Available The objective of current study was to evaluate the impact dietary non-fibrous carbohydrate ( NFC and ruminally degradable intake protein (DIP concentration have on ruminal fermentation , nutrient digestion and performance of local sheep. The animal had a mean of  liveweight 19.80 ±1.55 kg. four diets ,arranged in a 2x2 factorial ,were formulated to contain either 40 or 50 % NFC and 50 or 60 % of dietary crude protein as DIP .dietary DM contained 25 % Indonesian field grass and 75 % concentrate. Solvent –extracted or formaldehyd  2 % -treated soybean meal were used to alter DIP and corn or soybean hulls to alter NFC level. Percentage of  energy and NDF digestion was similar ( p<0,01 as DIP level decreased in the diets. The soybean hulls was fermentable and total VFA concentration in the rumen increased ( p<0.01, but N-NH3 concentration was decreased ( p<0.01 as DIP level decreased in the diets. Daily live weight gain ( 146.29±25.84 g and body composition ( fat, water , protein and mineral was similar ( p<0.05 among diets. The preponderance ruminal fermentation ,nutrient digestion and performance of local sheeps did not be improved by sincronization of energy and nitrogen release but may more likely be limited by either energy or nitrogen alone. (Animal Production 3(2: 53-61 (2001 Key Word : Carbohydrate, protein, rumen fermentation, nutrients digestion and performance

The in vitro digestibility of beef varies with its inherent ultimate pH.

Science.gov (United States)

Farouk, Mustafa M; Wu, Guojie; Frost, Deborah A; Clerens, Stefan; Knowles, Scott O

2014-11-01

Animal carcasses and cuts of meat are usually differentiated and valued according to size and compositional attributes. An underappreciated variable of red meat is its inherent ultimate pH (pHu) value, which affects organoleptic and processing characteristics. This study tests the hypothesis that high pHu aged meat would be more digestible than low pHu unaged (fresh) meat. Longissimus dorsi muscles collected from 59 bull carcasses had pHu values of 5.6-6.9. These were aged for 21 days at -1.5 °C, then raw and cooked (72 °C) samples were enzymatically digested at 37 °C with pepsin (pH 1.9 for 90 min) followed by pancreatin (pH 8.0 for an additional 120 min) to simulate conditions in the stomach and small intestine, respectively. Meat proteins and peptides in the digests were separated by 1D SDS PAGE. Regardless of pHu, ageing or cooking, most sarcoplasmic and myofibrillar proteins were rapidly digested by pepsin, with concomitant release of products identified by LC-MS/MS as mainly myosin-1, -2 and -7, α-actinin-2 or -3 and tropomyosin beta and alpha chains. These products were resistant to further digestion for the entire 210 min duration of the incubation. In terms of rate and extent of digestibility of these resistant products, high pHu > low pHu (P unaged (P meat samples increased with increasing pHu (P meat was highly digestible but could be further differentiated on the basis of its pHu and the ease of digestibility of proteins. Specific carcasses or cuts could be targeted to consumer groups in order to provide benefits and add value.

Solute carrier transporters: potential targets for digestive system neoplasms.

Science.gov (United States)

Xie, Jing; Zhu, Xiao Yan; Liu, Lu Ming; Meng, Zhi Qiang

2018-01-01

Digestive system neoplasms are the leading causes of cancer-related death all over the world. Solute carrier (SLC) superfamily is composed of a series of transporters that are ubiquitously expressed in organs and tissues of digestive systems and mediate specific uptake of small molecule substrates in facilitative manner. Given the important role of SLC proteins in maintaining normal functions of digestive system, dysregulation of these protein in digestive system neoplasms may deliver biological and clinical significance that deserves systemic studies. In this review, we critically summarized the recent advances in understanding the role of SLC proteins in digestive system neoplasms. We highlighted that several SLC subfamilies, including metal ion transporters, transporters of glucose and other sugars, transporters of urea, neurotransmitters and biogenic amines, ammonium and choline, inorganic cation/anion transporters, transporters of nucleotide, amino acid and oligopeptide organic anion transporters, transporters of vitamins and cofactors and mitochondrial carrier, may play important roles in mediating the initiation, progression, metastasis, and chemoresistance of digestive system neoplasms. Proteins in these SLC subfamilies may also have diagnostic and prognostic values to particular cancer types. Differential expression of SLC proteins in tumors of digestive system was analyzed by extracting data from human cancer database, which revealed that the roles of SLC proteins may either be dependent on the substrates they transport or be tissue specific. In addition, small molecule modulators that pharmacologically regulate the functions of SLC proteins were discussed for their possible application in the treatment of digestive system neoplasms. This review highlighted the potential of SLC family proteins as drug target for the treatment of digestive system neoplasms.

Effect of four processed animal proteins in the diet on digestibility and performance in laying hens.

Science.gov (United States)

van Krimpen, M M; Veldkamp, T; Binnendijk, G P; de Veer, R

2010-12-01

An experiment was performed to investigate the effect of animal vs. vegetable protein sources in the diet of laying hens on the development of hen performance. A diet containing protein sources of only vegetable origin was compared with 4 diets, each containing 1 of 4 processed animal proteins (PAP). Two PAP (Daka-58 and Sonac-60) were classified as meat meals, and the remaining 2 (Daka-40 and Sonac-50) were classified as meat and bone meals. First, fecal digestibility of nutrients in the PAP was determined in Lohmann Brown layers. Hens (n = 132) were housed in 22 cages (6 hens/cage) and allotted to 5 dietary treatments. In the PAP diets (4 replicates/treatment), 100 g/kg of CP of animal origin was added, replacing soybean meal and corn (Zea mays) in the basal diet (6 replicates/treatment). The PAP sources differed largely in chemical composition and digestibility coefficients. Energy content (AME(n)) varied from 1,817 (Daka-40) to 3,107 kcal/kg (Sonac-60), and digestible lysine varied from 15.4 (Daka-40) to 28.3 g/kg (Sonac-50). Subsequently, the effect of a control diet (without PAP) vs. 4 PAP diets (50 g/kg of CP of animal origin from the same batches as used in the digestibility study) on performance was determined. All diets were isocaloric (AME(n) = 2,825 kcal/kg) and isonitrogenous (digestible lysine = 6.8 g/kg). Hens were housed in 40 floor pens (12 hens/pen, 8 pens/treatment) from 20 to 40 wk of age. Feed intake levels of the hens fed the meat and bone meal diets were reduced compared with those of hens fed the meat meal diets, whereas the feed intake level of hens fed the control diet was intermediate. Laying hen performance differed between treatments, being was most favorable for the Sonac-50 treatment and most adverse for the Daka-40 treatment. Differences in laying hen performance seemed to be related partly to differences in feed intake and corresponding amino acid intake.

Deregulated HOXB7 expression predicts poor prognosis of patients with malignancies of digestive system.

Science.gov (United States)

Liu, Fang-Teng; Chen, Han-Min; Xiong, Ying; Zhu, Zheng-Ming

2017-07-26

Numerous studies have investigated the relationship between deregulated HOXB7 expression with the clinical outcome in patients with digestive stem cancers, HOXB7 has showed negative impacts but with varying levels. We aimed to comprehensively evaluate the prediction and prognostic value of HOXB7 in digestive stem cancers. Electronic databases updated to December 1, 2016 were retrieved to collect relevant eligible studies to quantitatively explore the potential roles of HOXB7 as a prognostic indicator in digestive system cancers. A total of 9 studies (n = 1298 patients) was included in this synthetical meta-analysis. The pooled hazard ratios suggested that high expression of HOXB7 protein was associated with poor prognosis of OS in patients with digestive system cancers (HR = 1.97, 95% CI: 1.65-2.28, p= 0.000), and HOXB7 protein could act as an independent prognostic factor for predicting OS of patients with digestive system cancers (HR: 2.02, 95% CI: 1.69-2.36, p = 0.000). Statistical significance was also observed in subgroup meta-analysis based on the cancer type, histology type, country, sample size and publication date. Furthermore, we examined the correlations between HOXB7 protein and clinicopathological features. It showed that altered expression of HOXB7 protein was correlated with tumor invasion (p = 0.000), lymph node status (p = 0.000), distant metastasis (p = 0.001) and TNM stage (p = 0.000). However, the expression of HOXB7 protein was not associated with age (p = 0.64), gender (p = 0.40) or levels of differentiation (p = 0.19). High expression of HOXB7 protein was associated with poor prognosis of patients with digestive system cancers, as well as clinicopathologic characteristics, including the tumor invasion, lymph node status, distant metastasis and TNM stage. The expression of HOXB7 protein was not associated with age, gender or levels of differentiation. HOXB7 protein expression level in tumor tissue might serve as a novel prognostic marker for

Protein Molecular Structures, Protein SubFractions, and Protein Availability Affected by Heat Processing: A Review

International Nuclear Information System (INIS)

Yu, P.

2007-01-01

The utilization and availability of protein depended on the types of protein and their specific susceptibility to enzymatic hydrolysis (inhibitory activities) in the gastrointestine and was highly associated with protein molecular structures. Studying internal protein structure and protein subfraction profiles leaded to an understanding of the components that make up a whole protein. An understanding of the molecular structure of the whole protein was often vital to understanding its digestive behavior and nutritive value in animals. In this review, recently obtained information on protein molecular structural effects of heat processing was reviewed, in relation to protein characteristics affecting digestive behavior and nutrient utilization and availability. The emphasis of this review was on (1) using the newly advanced synchrotron technology (S-FTIR) as a novel approach to reveal protein molecular chemistry affected by heat processing within intact plant tissues; (2) revealing the effects of heat processing on the profile changes of protein subfractions associated with digestive behaviors and kinetics manipulated by heat processing; (3) prediction of the changes of protein availability and supply after heat processing, using the advanced DVE/OEB and NRC-2001 models, and (4) obtaining information on optimal processing conditions of protein as intestinal protein source to achieve target values for potential high net absorbable protein in the small intestine. The information described in this article may give better insight in the mechanisms involved and the intrinsic protein molecular structural changes occurring upon processing.

Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

Science.gov (United States)

Gallardo, Pedro; Olivares, Alberto; Martínez-Yáñez, Rosario; Caamal-Monsreal, Claudia; Domingues, Pedro M.; Mascaró, Maite; Sánchez, Ariadna; Pascual, Cristina; Rosas, Carlos

2017-01-01

Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22–30°C) and sub-tropical (15–24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species. PMID:28620313

Can spectroscopy in combination with chemometrics replace minks in digestibility tests?

DEFF Research Database (Denmark)

Dahl, P.L.; Christensen, B.M.; Munck, L.

2000-01-01

One of the most relevant but expensive methods of assessing the quality of fish meal is the physiological digestibility test with minks. The purpose of this study was to determine whether spectroscopic and chemical analyses evaluated with chemometrics can replace minks in digestibility tests....... The spectroscopic methods used were the two complementary techniques of fluorescence emission and near-infrared reflectance. The investigation included 54 samples of high-quality fish meal ranging from 89.6 to 93.9 on the mink digestibility index. The investigation also included determination of seven quality...... parameters in the fish meal to substantiate the spectroscopic models on the mink digestibility. These quality parameters include the content of protein, oil, water, water-soluble protein, ash and the biogenic substance cadaverine as well as the titration value. The study demonstrates that the mink...

Effect of milk protein composition of a model infant formula on the physicochemical properties of in vivo gastric digestates.

Science.gov (United States)

Tari, N Rafiee; Fan, M Z; Archbold, T; Kristo, E; Guri, A; Arranz, E; Corredig, M

2018-04-01

We investigated the effect of protein composition and, in particular, the presence of whey proteins or β-casein on the digestion behavior of a model infant formula using an in vivo piglet model. Three isocaloric diets optimized for piglets were prepared with the same concentrations of protein. For protein source, 1 diet contained only whey proteins and 2 contained a casein:whey protein ratio of 40:60 but differed in the amount of β-casein. To obtain the desired protein compositions, skim milk was microfiltered at 7 or 22°C, and retentates and permeates were combined with whey protein isolate. The diets were optimized to the nutritional needs of the piglets and fed to 24 newborn piglets for 18 d. Eight piglets were also fed ad libitum with sow milk and considered only as reference (not included in the statistical analysis). The study was carried out in 2 blocks, killing the animals 60 and 120 min after the last meal. All gastric contents, regardless of diet, showed a wide range of pH. Postprandial time did not affect the pH or physical properties of the gastric digesta. The digesta from whey protein-casein formulas showed significantly higher viscosity, a higher storage modulus, and a denser microstructure than digesta obtained from piglets fed whey protein formula. The β-casein:total casein ratio at the level used in this study did not significantly affect the physical and chemical properties of the stomach digestate. Although caseins showed extensive gastric hydrolysis, whey proteins remained largely intact at both postprandial times. The results indicate that the presence of different concentrations of milk proteins can be critical to the digestion properties of the food matrix and may affect the nutritional properties of the components. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Hydrocolloids Decrease the Digestibility of Corn Starch, Soy Protein, and Skim Milk and the Antioxidant Capacity of Grape Juice.

Science.gov (United States)

Yi, Yue; Jeon, Hyeong-Ju; Yoon, Sun; Lee, Seung-Min

2015-12-01

Hydrocolloids have many applications in foods including their use in dysphagia diets. We aimed to evaluate whether hydrocolloids in foods affect the digestibility of starch and protein, and their effects on antioxidant capacity. The thickening hydrocolloids: locust bean gum and carboxymethyl cellulose, and the gel-forming agents: agar agar, konjac-glucomannan, and Hot & Soft Plus were blended with corn starch and soy protein, skim milk, or grape juice and were examined for their in vitro-digestability by comparing the reducing sugar and trichloroacetic acid (TCA)-soluble peptide, for antioxidant capacity by total polyphenol contents and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. The hydrocolloids resulted in a decrease in starch digestibility with the gel-forming agents. Hydrocolloids diminished TCA-soluble peptides in skim milk compared to soy protein with the exception of locust bean gum and decreased free radical scavenging capacities and total phenolic contents in grape juice. Our findings may provide evidence for the use of hydro-colloids for people at risk of nutritional deficiencies such as dysphagia patients.

Effects of processing moisture on the physical properties and in vitro digestibility of starch and protein in extruded brown rice and pinto bean composite flours.

Science.gov (United States)

Sumargo, Franklin; Gulati, Paridhi; Weier, Steven A; Clarke, Jennifer; Rose, Devin J

2016-11-15

The influence of pinto bean flour and processing moisture on the physical properties and in vitro digestibility of rice-bean extrudates has been investigated. Brown rice: pinto bean flour (0%, 15%, 30%, and 45% bean flour) were extruded under 5 moisture conditions (17.2%, 18.1%, 18.3%, 19.5%, and 20.1%). Physical properties [bulk density, unit density, radial expansion, axial expansion, overall expansion, specific volume, hardness, color, water solubility index, and water absorption index] and in vitro starch and protein digestibilities were determined. Increasing bean flour and processing moisture increased density and hardness while decreasing expansion. Rapidly digestible starch decreased and resistant starch increased as bean substitution and processing moisture increased. In vitro protein digestibility increased with increasing bean flour or with decreasing processing moisture. Incorporating bean flour into extruded snacks can negatively affect physical attributes (hardness, density, and expansion) while positively affecting in vitro starch (decrease) and protein (increase) digestibilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of dietary protein and fructooligosaccharides on fecal fermentative end-products, fecal bacterial populations and apparent total tract digestibility in dogs.

Science.gov (United States)

Pinna, Carlo; Vecchiato, Carla Giuditta; Bolduan, Carmen; Grandi, Monica; Stefanelli, Claudio; Windisch, Wilhelm; Zaghini, Giuliano; Biagi, Giacomo

2018-03-20

Feeding dogs with diets rich in protein may favor putrefactive fermentations in the hindgut, negatively affecting the animal's intestinal environment. Conversely, prebiotics may improve the activity of health-promoting bacteria and prevent bacterial proteolysis in the colon. The aim of this study was to evaluate the effects of dietary supplementation with fructooligosaccharides (FOS) on fecal microbiota and apparent total tract digestibility (ATTD) in dogs fed kibbles differing in protein content. Twelve healthy adult dogs were used in a 4 × 4 replicated Latin Square design to determine the effects of four diets: 1) Low protein diet (LP, crude protein (CP) 229 g/kg dry matter (DM)); 2) High protein diet (HP, CP 304 g/kg DM); 3) Diet 1 + 1.5 g of FOS/kg; 4) Diet 2 + 1.5 g of FOS/kg. The diets contained silica at 5 g/kg as a digestion marker. Differences in protein content were obtained using different amounts of a highly digestible swine greaves meal. Each feeding period lasted 28 d, with a 12 d wash-out in between periods. Fecal samples were collected from dogs at 0, 21 and 28 d of each feeding period. Feces excreted during the last five days of each feeding period were collected and pooled in order to evaluate ATTD. Higher fecal ammonia concentrations were observed both when dogs received the HP diets (p < 0.001) and the supplementation with FOS (p < 0.05). The diets containing FOS resulted in greater ATTD of DM, Ca, Mg, Na, Zn, and Fe (p < 0.05) while HP diets were characterized by lower crude ash ATTD (p < 0.05). Significant interactions were observed between FOS and protein concentration in regards to fecal pH (p < 0.05), propionic acid (p < 0.05), acetic to propionic acid and acetic + n-butyric to propionic acid ratios (p < 0.01), bifidobacteria (p < 0.05) and ATTD of CP (p < 0.05) and Mn (p < 0.001). A relatively moderate increase of dietary protein resulted in higher concentrations of ammonia in

The influence of irradiation treatment on gossypol and protein digestibility of decorticated cottonseed meal for Broiler chicks

International Nuclear Information System (INIS)

Farag, M.D.H.

2000-01-01

The Effect of gamma irradiation (5-20 kGy) on the chemical composition, soluble protein, available lysine, gossypol, in-vitro and in vivo digestibility of decorticated cottonseed meal (CSM) and the performance of broilers fed processed CSM were investigated. Radiation treatment of CSM at dose levels of 5, 10, 15 and 20 kGy did not affect moisture, crude protein, ether extract, crude fiber, ash and NFW content. However, the treatment reduced soluble protein by 4.18, 7.82, 10.91, 13.46%, respectively. Fluorodinitrobenzene-available lysine concentration reduced by 4.48, 8.12, 17.65 and 21.29% respectively. The concentrations of total gossypol decreased by 7.97, 15.78, 19.92 and 25.39% and free gossypol by 3.74, 7.85, 18.43 and 28.01%, respectively. The digestibility of CSM protein was increased by 5.3, 9.0, 16.6 and 17.2%, for in-vitro digestibility and by 4.8, 7.3, 9.4 and 12.9% for in-vivo due to treatment with 5,10, 15 and 20 kGy, respectively. From 7 to 42 days, arbor acres broilers were freely given iso energetic and iso nitrogenous : corn-soy control diet or diets containing 300 g kg -1 raw or irradiated CSM at 4, 15 or 20 kGy. Intake of raw CSM affected growth, feed intake and feed conversion as compared with birds receiving the control diet

In vitro starch digestion correlates well with rate and extent of starch digestion in broiler chickens

NARCIS (Netherlands)

Weurding, R.E.; Veldman, R.; Veen, W.A.G.; Aar, van der P.J.; Verstegen, M.W.A.

2001-01-01

Current feed evaluation systems for poultry are based on digested components (fat, protein and nitrogen-free extracts). Digestible starch is the most important energy source in broiler chicken feeds and is part of the nitrogen-free extract fraction. Digestible starch may be predicted using an in

Changes on antioxidant activity of microwave-treated protein hydrolysates after simulated gastrointestinal digestion: Purification and identification.

Science.gov (United States)

Ketnawa, Sunantha; Wickramathilaka, Malithi; Liceaga, Andrea M

2018-07-15

Two samples of trout frame protein hydrolysates were prepared by Microwave Pretreatment followed by Conventional Enzymatic hydrolysis (MPCE) and Non-Pretreated followed by Microwave-assisted Enzymatic hydrolysis (NPME), respectively, were subjected to simulated gastrointestinal digestion. Changes on degree of hydrolysis, antioxidant activity, molecular weight, and amino acid composition between undigested and after gastrointestinal digestion of peptides were investigated. Comparing to undigested peptides, a breakdown of MPCE and NPME into smaller molecules was observed. Degree of hydrolysis, ABTS + radical scavenging activity and reducing power increased (P digestion. A purified peptide from GI-MPCE had two possible sequences, NGRLGYSEGVM or GNRLGYSWDD (1182.65 Da). Whereas GI-NPME had two peptides IRGPEEHMHR or RVAPEEHMHR (1261.77 Da) and SAGVPRHK or SARPRHK (962.63 Da). These results indicate that digested hydrolysates can be a rich source of antioxidants. Isolated peptides extracted from trout frame by-products could be new food ingredients used as natural antioxidants. Copyright © 2018 Elsevier Ltd. All rights reserved.

Metionina mais cistina digestível e relação metionina mais cistina digestível: lisina para codornas japonesas Digestible methionine plus cystine and relation digestible methionine plus cystine: lysine for japanese quails

Directory of Open Access Journals (Sweden)

Julio Francisco Valiati Marin

2011-09-01

Full Text Available Objetivou-se determinar o melhor nível de metionina mais cistina digestível e a melhor relação metionina mais cistina digestível:lisina digestível em diferentes níveis de proteína para codorna em postura. Foram utilizadas 400 codornas japonesas produtoras de ovos de consumo com 45 dias de idade, em delineamento inteiramente casualizado, num esquema fatorial 2 x 5, dois níveis de proteína bruta (19,5% e 21,5% e cinco níveis de metionina mais cistina digestível (0,60%; 0,67%; 0,74%; 0,81% e 0,88%, com cinco repetições e oito aves por unidade experimental. Foram analisadas as taxas de postura (%, peso médio dos ovos (g, massa de ovos (g de ovos/ave/dia, consumo de ração (g/ave/dia, conversão alimentar (g de ração/g de ovos, peso e porcentagem de gema (g e %, peso e porcentagem de clara (g e % e peso e porcentagem de casca (g e %. Para o nível de 19,5% de proteína 0,60% de metionina mais cistina digestível e relação metionina mais cistina digestível:lisina digestível de 0,66% foram suficientes para otimizar a produção. Para o nível de 21,5% de proteína 0,851% de metionina mais cistina digestível com relação metionina mais cistina digestível:lisina digestível de 0,935% com consumo diário de 223,3mg/ave levou a uma melhor produção de ovos de codornas.This research had the purpose to determine the best level of digestible methionine plus cystine and the best relation of digestible methionine plus cystine:digestible lysine in different levels of protein for laying Japanese quails. 400 laying Japanese quails, with 45 days of age were used in a completely randomized design, with a factorial 2 x 5, two crude protein levels (19,5% and 21,5% and five levels of digestible methionine plus cystine (0,60%; 0,67%; 0,74%; 0,81% e 0,88%, with five replicates and eight quails per experimental unity. There were analysis of the posture rate (%, egg average weight (g egg mass (egg grams/bird/day, feed intake (g/bird/day, feed

Phosphopeptide Enrichment by Covalent Chromatography after Derivatization of Protein Digests Immobilized on Reversed-Phase Supports

Science.gov (United States)

Nika, Heinz; Nieves, Edward; Hawke, David H.; Angeletti, Ruth Hogue

2013-01-01

A rugged sample-preparation method for comprehensive affinity enrichment of phosphopeptides from protein digests has been developed. The method uses a series of chemical reactions to incorporate efficiently and specifically a thiol-functionalized affinity tag into the analyte by barium hydroxide catalyzed β-elimination with Michael addition using 2-aminoethanethiol as nucleophile and subsequent thiolation of the resulting amino group with sulfosuccinimidyl-2-(biotinamido) ethyl-1,3-dithiopropionate. Gentle oxidation of cysteine residues, followed by acetylation of α- and ε-amino groups before these reactions, ensured selectivity of reversible capture of the modified phosphopeptides by covalent chromatography on activated thiol sepharose. The use of C18 reversed-phase supports as a miniaturized reaction bed facilitated optimization of the individual modification steps for throughput and completeness of derivatization. Reagents were exchanged directly on the supports, eliminating sample transfer between the reaction steps and thus, allowing the immobilized analyte to be carried through the multistep reaction scheme with minimal sample loss. The use of this sample-preparation method for phosphopeptide enrichment was demonstrated with low-level amounts of in-gel-digested protein. As applied to tryptic digests of α-S1- and β-casein, the method enabled the enrichment and detection of the phosphorylated peptides contained in the mixture, including the tetraphosphorylated species of β-casein, which has escaped chemical procedures reported previously. The isolates proved highly suitable for mapping the sites of phosphorylation by collisionally induced dissociation. β-Elimination, with consecutive Michael addition, expanded the use of the solid-phase-based enrichment strategy to phosphothreonyl peptides and to phosphoseryl/phosphothreonyl peptides derived from proline-directed kinase substrates and to their O-sulfono- and O-linked β-N-acetylglucosamine (O

Antacid medication inhibits digestion of dietary proteins and causes food allergy: a fish allergy model in BALB/c mice.

Science.gov (United States)

Untersmayr, Eva; Schöll, Isabella; Swoboda, Ines; Beil, Waltraud J; Förster-Waldl, Elisabeth; Walter, Franziska; Riemer, Angelika; Kraml, Georg; Kinaciyan, Tamar; Spitzauer, Susanne; Boltz-Nitulescu, George; Scheiner, Otto; Jensen-Jarolim, Erika

2003-09-01

Digestible proteins were supposed to be irrelevant for oral sensitization and induction of food allergy. Approximately 10% of the adult population uses antacids for the treatment of dyspeptic disorders, drugs that hinder peptic digestion. In these patients, proteins that are normally degradable might act as food allergens. We aimed to study the influence of antacid intake on the allergenicity of dietary proteins, taking sturgeon caviar and parvalbumin, the major fish allergen, as examples. Caviar proteins and recombinant parvalbumin from carp, rCyp c 1, were applied for intragastric feedings with or without the antacids sucralfate, ranitidine or omeprazole, using a Balb/c mouse model. Both caviar proteins and parvalbumin were rapidly degraded in an in vitro digestion assay at pH 2.0, but not at pH 5.0, imitating the effect of antacids. The groups fed with caviar in combination with ranitidine hydrochloride intramuscularly or sucralfate orally had significant levels of caviar-specific IgE antibodies (P allergy in these groups was further evidenced by oral provocation tests and positive immediate-type skin reactivity. In contrast, feedings with caviar alone led to antigen-specific T-cell tolerance. None of the groups showed immune reactivity against the daily mouse diet. As a proof of the principle, feeding mice with parvalbumin in combination with ranitidine or omeprazole intramuscularly induced allergen-specific IgE antibodies (P allergy.

In vitro digestibility, protein composition and techno-functional properties of Saskatchewan grown yellow field peas (Pisum sativum L.) as affected by processing.

Science.gov (United States)

Ma, Zhen; Boye, Joyce I; Hu, Xinzhong

2017-02-01

Saskatchewan grown yellow field pea was subjected to different processing conditions including dehulling, micronization, roasting, conventional/microwave cooking, germination, and combined germination and conventional cooking/roasting. Their nutritional and antinutritional compositions, functional properties, microstructure, thermal properties, in vitro protein and starch digestibility, and protein composition were studied. Processed field peas including conventional cooked yellow peas (CCYP), microwave cooked yellow peas (MCYP), germinated-conventional cooked yellow peas (GCCYP), and germinated-roasted yellow peas (GRYP) exhibited the significantly higher in vitro protein digestibility (IVPD), which was in accordance with their significantly lower trypsin inhibitor activity and tannin content. The SDS-PAGE and size exclusion HPLC profiles of untreated pea proteins and their hydrolysates also confirmed the IVPD result that these four treatments facilitated the hydrolysis of pea proteins to a greater extent. The CCYP, MCYP, GCCYP, and GRYP also exhibited significantly higher starch digestibility which was supported by their lower onset (T o ), peak (T p ), and conclusion (T c ) temperatures obtained from DSC thermogram, their lower pasting properties and starch damage results, as well as their distinguished amorphous flakes' configuration observed on the scanning electron microscopic image. LC/ESI-MS/MS analysis following in-gel digests of SDS-PAGE separated proteins allowed detailed compositional characterization of pea proteins. The present study would provide fundamental information to help to better understand the functionality of field peas as ingredients, and particularly in regards to agri-food industry to improve the process efficiency of field peas with enhanced nutritional and techno-functional qualities. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Anaerobic digestion of lignocellulosic biomass with animal digestion mechanisms].

Science.gov (United States)

Wu, Hao; Zhang, Pan-Yue; Guo, Jian-Bin; Wu, Yong-Jie

2013-02-01

Lignocellulosic material is the most abundant renewable resource in the earth. Herbivores and wood-eating insects are highly effective in the digestion of plant cellulose, while anaerobic digestion process simulating animal alimentary tract still remains inefficient. The digestion mechanisms of herbivores and wood-eating insects and the development of anaerobic digestion processes of lignocellulose were reviewed for better understanding of animal digestion mechanisms and their application in design and operation of the anaerobic digestion reactor. Highly effective digestion of lignocellulosic materials in animal digestive system results from the synergistic effect of various digestive enzymes and a series of physical and biochemical reactions. Microbial fermentation system is strongly supported by powerful pretreatment, such as rumination of ruminants, cellulase catalysis and alkali treatment in digestive tract of wood-eating insects. Oxygen concentration gradient along the digestive tract may stimulate the hydrolytic activity of some microorganisms. In addition, the excellent arrangement of solid retention time, digesta flow and end product discharge enhance the animal digestion of wood cellulose. Although anaerobic digestion processes inoculated with rumen microorganisms based rumen digestion mechanisms were developed to treat lignocellulose, the fermentation was more greatly limited by the environmental conditions in the anaerobic digestion reactors than that in rumen or hindgut. Therefore, the anaerobic digestion processes simulating animal digestion mechanisms can effectively enhance the degradation of wood cellulose and other organic solid wastes.

Enhancement of anaerobic sludge digestion by high-pressure homogenization.

Science.gov (United States)

Zhang, Sheng; Zhang, Panyue; Zhang, Guangming; Fan, Jie; Zhang, Yuxuan

2012-08-01

To improve anaerobic sludge digestion efficiency, the effects of high-pressure homogenization (HPH) conditions on the anaerobic sludge digestion were investigated. The VS and TCOD were significantly removed with the anaerobic digestion, and the VS removal and TCOD removal increased with increasing the homogenization pressure and homogenization cycle number; correspondingly, the accumulative biogas production also increased with increasing the homogenization pressure and homogenization cycle number. The optimal homogenization pressure was 50 MPa for one homogenization cycle and 40 MPa for two homogenization cycles. The SCOD of the sludge supernatant significantly increased with increasing the homogenization pressure and homogenization cycle number due to the sludge disintegration. The relationship between the biogas production and the sludge disintegration showed that the accumulative biogas and methane production were mainly enhanced by the sludge disintegration, which accelerated the anaerobic digestion process and improved the methane content in the biogas. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tsetse salivary gland proteins 1 and 2 are high affinity nucleic acid binding proteins with residual nuclease activity.

Directory of Open Access Journals (Sweden)

Guy Caljon

Full Text Available Analysis of the tsetse fly salivary gland EST database revealed the presence of a highly enriched cluster of putative endonuclease genes, including tsal1 and tsal2. Tsal proteins are the major components of tsetse fly (G. morsitans morsitans saliva where they are present as monomers as well as high molecular weight complexes with other saliva proteins. We demonstrate that the recombinant tsetse salivary gland proteins 1&2 (Tsal1&2 display DNA/RNA non-specific, high affinity nucleic acid binding with K(D values in the low nanomolar range and a non-exclusive preference for duplex. These Tsal proteins exert only a residual nuclease activity with a preference for dsDNA in a broad pH range. Knockdown of Tsal expression by in vivo RNA interference in the tsetse fly revealed a partially impaired blood digestion phenotype as evidenced by higher gut nucleic acid, hematin and protein contents.

Sulfur Removal by Adding Iron During the Digestion Process of High-sulfur Bauxite

Science.gov (United States)

Zhanwei, Liu; Hengwei, Yan; Wenhui, Ma; Keqiang, Xie; Dunyong, Li; Licong, Zheng; Pengfei, Li

2018-04-01

This paper proposes a novel approach to sulfur removal by adding iron during the digestion process. Iron can react with high-valence sulfur (S2O3 2-, SO3 2-, SO4 2-) to generate S2- at digestion temperature, and then S2- enter red mud in the form of Na3FeS3 to be removed. As iron dosage increases, high-valence sulfur concentration decreases, but the concentration of S2- increases; sulfur digestion rate decreases while sulfur content in red mud markedly increases; the alumina digestion rate, conversely, remains fairly stable. So sulfur can be removed completely by adding iron in digestion process, which provide a theoretical basis for the effective removal of sulfur in alumina production process.

DIGESTION OF HIGH FIBER DIET IN SHEEP AND GOAT OF JENEPPONTO

Directory of Open Access Journals (Sweden)

D.P. Rahardja

2014-10-01

Full Text Available Four does (goat, G and four ewes (sheep, S of Jeneponto were fed chaffed rice straw hay (3.7%crude protein, 63.5% cell wall constituents, 44.5% acid detergent fiber and 6.2% acid detergent lignin,all based on dry matter. The intakes and digestibility of the diet by G and S were compared. Bothspecies consumed the same level of the diet. G digested dry matter, organic matter, crude protein, crudefiber, and lignin of the diet to a significant higher extent than did by S. The superiority of G over S indigesting the diet was attributable with longer retention time of ruminal fluid and particulate matters inthe rumen and the entire gut, which then resulted in higher proportion of small size particles (<1 mmsieve, higher proportions of propionic, butyric, valeric and isovaleric acid concentrations produced inthe rumen. Additionally for further studies, there were some possibilities of G having a better chewingactivity (duration and intensity, and ability to maintain higher rumen ammonia levels by a greater urearecycle to the rumen, particularly through salivation.

Functional and anti-nutritional properties, in-vitro protein digestibility and amino acid composition of dehulled afzelia africana seeds

International Nuclear Information System (INIS)

Ogungbenle, H.N.; Omaejalile, M.

2010-01-01

Analysis of Afzelia africana seed flour showed that the seeds possessed high water absorption capacity (128.31%), good oil absorption capacity (588.49%) and fairly good emulsion property (35.25%). However, it had the Least gelation concentration (6 .00% w/v) and foaming properties ( 8.00%,3 .00%). Anti-nutritional factors were very low, with the highest being phytate (13.59/o) and tannin the least (0.43%). Total amino acid composition was 796.6 mg/g protein. Essentiaal amino acids (48.5%)w ere in high proportion with in-vitro digestibility of 71.5%. (author)

Quarterly intrinsic disorder digest (January-February-March, 2014)

OpenAIRE

DeForte, Shelly; Reddy, Krishna D.; Uversky, Vladimir N.

2016-01-01

This is the 5th issue of the Digested Disorder series that represents a reader's digest of the scientific literature on intrinsically disordered proteins. We continue to use only 2 criteria for inclusion of a paper to this digest: The publication date (a paper should be published within the covered time frame) and the topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the first quarter of 2014; i.e., during ...

Denaturation and in Vitro Gastric Digestion of Heat-Treated Quinoa Protein Isolates Obtained at Various Extraction pH

NARCIS (Netherlands)

Ruiz, Geraldine Avila; Opazo-Navarrete, Mauricio; Meurs, Marlon; Minor, Marcel; Sala, Guido; Boekel, van Tiny; Stieger, Markus; Janssen, Anja E.M.

2016-01-01

The aim of this study was to determine the influence of heat processing on denaturation and digestibility properties of protein isolates obtained from sweet quinoa (Chenopodium quinoa Willd) at various extraction pH values (8, 9, 10 and 11). Pretreatment of suspensions of protein isolates at 60,

Actinidin from kiwifruit (Actinidia deliciosa cv. Hayward) increases the digestion and rate of gastric emptying of meat proteins in the growing pig.

Science.gov (United States)

Montoya, Carlos A; Rutherfurd, Shane M; Olson, Trent D; Purba, Ajitpal S; Drummond, Lynley N; Boland, Mike J; Moughan, Paul J

2014-03-28

The present study aimed to investigate the effect of dietary actinidin on the kinetics of gastric digestion of beef muscle proteins and on the rate of stomach emptying in growing pigs. For this purpose, 120 pigs (mean body weight 28 (sd 2·9) kg) were fed beef muscle protein-based diets containing either actinidin (fresh green kiwifruit pulp or gold kiwifruit pulp supplemented with purified actinidin) or no actinidin (fresh gold kiwifruit pulp or green kiwifruit pulp with inactivated actinidin). Additionally, fifteen pigs were fed with a protein-free diet to determine the endogenous protein flow. Pigs were euthanised at exactly 0·5, 1, 3, 5 and 7 h postprandially (n 6 per time point for each kiwifruit diet and n 3 for protein-free diet). Stomach chyme was collected for measuring gastric retention, actinidin activity, individual beef muscle protein digestion based on SDS-PAGE and the degree of hydrolysis based on the appearance of free amino groups. The stomach emptying of DM and N was faster when actinidin was present in the diet (P34 kDa; P< 0·05). In conclusion, dietary actinidin fed in the form of fresh green kiwifruit increased the rate of gastric emptying and the digestion of several beef muscle proteins.

Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: Impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion

Science.gov (United States)

Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

2014-03-01

An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region.

Intestinal digestibility of amino acids in rumen-undegraded protein estimated using a precision-fed cecectomized rooster bioassay: II. Distillers dried grains with solubles and fish meal.

Science.gov (United States)

Boucher, S E; Calsamiglia, S; Parsons, C M; Stein, H H; Stern, M D; Erickson, P S; Utterback, P L; Schwab, C G

2009-12-01

The objectives of this experiment were to measure intestinal digestibility of AA in the rumen-undegraded protein fraction (RUP-AA) of distillers dried grains with solubles (DDGS) and fish meal (FM) samples and to determine whether these feeds contain a constant protein fraction that is undegradable in the rumen and indigestible in the small intestine, as assumed in the French Institut National de la Recherche Agronomique (Paris, France) and Scandinavian AAT-PBV (AAT = AA absorbed from small intestine; PBV = protein balance in the rumen) models. Five sources of DDGS and 5 sources of FM were obtained from Feed Analysis Consortium, Inc. (Champaign, IL). To obtain the rumen-undegradable protein fraction, samples were ruminally incubated in situ for 16 h in 4 lactating cows, and the collected rumen-undegraded residues (RUR) were pooled by sample. Subsamples of the intact feeds and RUR were crop-intubated to 4 cecectomized roosters, and total excreta were collected for 48 h. Intact feeds, RUR, and excreta were analyzed for AA. Basal endogenous AA loss estimates were obtained from fasted birds and were used to calculate standardized digestibility of RUP-AA and AA in the intact feeds. Indigestibility coefficients of the intact feeds were calculated as (100 - % standardized AA digestibility), and indigestibility of the RUR was calculated as [(100 - % ruminal degradation of AA) x (100 - % standardized RUP-AA digestibility)/100]. Results indicate that standardized digestibility of feed-AA differs from RUP-AA for DDGS samples but not for FM samples, and that standardized digestibility of individual AA differs within samples. For the DDGS samples, standardized feed-AA and RUP-AA digestibility values were most often lowest for His and Lys and highest for Met and Trp. For FM samples, standardized feed-AA and RUP-AA digestibility values were most often lowest for His and highest for Trp. Results also indicate that DDGS and most FM samples do not contain a constant protein fraction

Chemical Composition, Starch Digestibility and Antioxidant Capacity of Tortilla Made with a Blend of Quality Protein Maize and Black Bean

Directory of Open Access Journals (Sweden)

Luis A. Bello-Pérez

2011-12-01

Full Text Available Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50% and the predicted glycemic index (88 to 80 of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g than control tortilla (7.8 μmol Trolox eq/g. The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics.

Silicate minerals for CO2 scavenging from biogas in Autogenerative High Pressure Digestion

NARCIS (Netherlands)

Lindeboom, R.E.F.; Ferrer, I.; Weijma, J.; Lier, van J.B.

2013-01-01

Autogenerative High Pressure Digestion (AHPD) is a novel concept that integrates gas upgrading with anaerobic digestion by selective dissolution of CO2 at elevated biogas pressure. However, accumulation of CO2 and fatty acids after anaerobic digestion of glucose resulted in pH 3–5, which is

The digestive system of 1-week-old Jersey calves is well suited to digest, absorb, and incorporate protein and energy into tissue growth even when calves are fed a high plane of milk replacer.

Science.gov (United States)

Liang, Yu; Carroll, Jeffery A; Ballou, Michael A

2016-03-01

The objectives of the current study were to determine the apparent digestibilities of nitrogen, organic matter, ash, and energy as well as investigate the nitrogen retention of calves fed different planes of milk replacer nutrition during the first week of life. Twelve Jersey calves were blocked by body weight at birth and randomly assigned to either a high plane of nutrition (HPN) or low plane of nutrition (LPN) treatment. The HPN calves were offered 19.2g of dry matter/kg of body weight of a 28% all-milk crude protein and 20% fat milk replacer. The LPN calves were fed 11.6g of dry matter/kg of body weight of a 20% all-milk crude protein and 20% fat milk replacer. All calves were given 3 L of pooled colostrum within 1h of birth after which they were assigned to treatments; no starter was offered during the study. Calves were given 1 d to adapt to their treatments and environment, so calves were 30 to 36 h old at the start of data collection. The study was divided into two 72-h periods. Total collection of feces occurred over each 72 h period, and total urine was collected for the last 24h of each period. Peripheral blood samples were collected at the beginning and end of each period and analyzed for plasma glucose and urea nitrogen concentrations. Data are reported as HPN vs. LPN, respectively. Fecal scores were greater for HPN calves during both periods; however, no difference was found in the dry matter percentage of feces (30.9 vs. 31.9 ± 0.06). No differences were found between treatments in either digestible or metabolizable energy efficiencies, which averaged 93.3 and 83.7%, respectively. A treatment × period interaction was found on the percentage of intake nitrogen retained, in which calves fed the HPN had a greater percentage of intake nitrogen retained during period 1 (87.9 vs. 78.4 ± 1.79%), but was not different from calves fed the LPN during period 2 (85.4 vs. 84.9 ± 1.79%). From these data therefore, we conclude that healthy neonatal calves have

Optimised anaerobic treatment of house-sorted biodegradable waste and slaughterhouse waste in a high loaded half technical scale digester.

Science.gov (United States)

Resch, C; Grasmug, M; Smeets, W; Braun, R; Kirchmayr, R

2006-01-01

Anaerobic co-digestion of organic wastes from households, slaughterhouses and meat processing industries was optimised in a half technical scale plant. The plant was operated for 130 days using two different substrates under organic loading rates of 10 and 12 kgCOD.m(-3).d(-1). Since the substrates were rich in fat and protein components (TKN: 12 g.kg(-1) the treatment was challenging. The process was monitored on-line and in the laboratory. It was demonstrated that an intensive and stable co-digestion of partly hydrolysed organic waste and protein rich slaughterhouse waste can be achieved in the balance of inconsistent pH and buffering NH4-N. In the first experimental period the reduction of the substrate COD was almost complete in an overall stable process (COD reduction >82%). In the second period methane productivity increased, but certain intermediate products accumulated constantly. Process design options for a second digestion phase for advanced degradation were investigated. Potential causes for slow and reduced propionic and valeric acid degradation were assessed. Recommendations for full-scale process implementation can be made from the experimental results reported. The highly loaded and stable codigestion of these substrates may be a good technical and economic treatment alternative.

Combining protein extraction and anaerobic digestion to produce feed, fuel and fertilizer from green biomass – An organic biorefinery concept

DEFF Research Database (Denmark)

Fernandez, Maria Santamaria; Salces, Beatriz Molinuevo; Lübeck, Mette

Organically grown green biomass (red clover, clover grass) was investigated as a resource for organic feed and organic fertilizer by combination of proteins extraction and anaerobic digestion of the residues. Extraction of proteins from both crops revealed very favourable amino acid composition...... for the use as animal feed. The residual 90% of organic matter, leaving the separation as solid press cake and brown juice was subjected to anaerobic digestion to produce biogas and fertilizer. Methane yields of 220-310 and 430-540 ml CH4/g VS were obtained for press cake and brown juice, respectively...

Ileal and faecal protein digestibility measurement in humans and other non-ruminants - a comparative species view

NARCIS (Netherlands)

Hendriks, W.H.; Baal, van J.; Bosch, G.

2012-01-01

A comparative non-ruminant species view of the contribution of the large intestinal metabolism to inaccuracies in nitrogen and amino acid absorption measurements is provided to assess potential implications for the determination of crude protein/amino acid digestibility in adult humans consuming

Food allergen digestibility: The influence on allergenicity

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

potential exist. Resistance to digestion is therefore a test parameter included in the safety assessment of the allergenic potential of novel proteins in genetically modified foods. In recent years, the association between resistance to digestion and allergenic potential has been challenged. When reviewing......Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. What makes a dietary protein a food allergen has not yet been established, though several characteristics have been proposed to be shared by the food allergens. One of the features believed...... existing data from digestibility studies on known food allergens, it becomes evident that food allergens do not necessarily resist digestion. However, the choice of assay conditions, the method used for detection of residual intact protein as well as fragments hereof greatly influences the outcome. Studies...

Estimation of the True Digestibility of Rumen Undegraded Dietary Protein in the Small Intestine of Ruminants by the Mobile Bag Technique

DEFF Research Database (Denmark)

Hvelplund, Torben; Weisbjerg, Martin Riis; Andersen, L. S.

1992-01-01

Dietary protein degraded to various extents by varying the time of rumen incubation was prepared from eight concentrates and four roughages. Intestinal digestibility was obtained using the mobile bag technique on intact protein and on the samples of undegraded dietary protein from each feed. The ...

Effect of exogenous cellulase enzyme on feed digestibility in lamb

International Nuclear Information System (INIS)

Boonek, Lerchat; Shinkoi, Henrry S; Piadang, Nattayana

2006-09-01

The aim of this study was to determine the effect of exogenous enzyme on digestibility and N retention in lamb. Eight lambs were randomly allocated to 2 experiment group in group comparison design trial. Experimental treatments were: 1) CTL (No enzyme) and 2 50NZ (Mixed enzyme with high cellulase at 50g/100kg.feed). The digestibility study showed that Exogenous enzyme increased (P<0.05) dry matter and crude protein digestibility of treated lamb compared to those of control. A similar trend (P=0.11) was observed for the NDF digestibility. Mean values for dry matter digestibility were 57.86 and 69.83% and for protein digestibility were 64.76 and 73.38%, for CTL and 50NZ, respectively). The N intake was similar among treatment, averaging 22.57g/head/day. Percent N retained of 50 NZ treated lambs was higher (P<.05) than those of CTL group (mean value were 47.74 and 59.07 for CTC and 50NZ, respectively). Feed efficiency or feed conversion ratio was numerically improved for enzyme-treated groups. Overall, the results of this study provide evidence that mixed cellulase enzyme can be used to improver performance of lambs as compare to non-enzyme diet.

Experimental assessment of factors influencing dewatering properties of thermophilically digested biosolids

Energy Technology Data Exchange (ETDEWEB)

Zhou, Jianpeng; Mavinic, Donald S.; Kelly, Harlan G.; Ramey, William D.

2003-07-01

Beneficial land application of processed wastewater sludges (biosolids) is a cost-effective, and environmentally sustainable option for the final disposal of sludges, because nutrients and organic matters in the sludge are recovered and reused as a resource. Thermophilic sludge digestion produces Class A biosolids, which can be reused without restrictions. Recent experience from full-scale thermophilic sludge digestion facilities in North America revealed that, dewatering thermophilically digested biosolids required more polymers to condition than mesophilically digested biosolids. This paper reports a laboratory study that investigated factors having significant impacts on dewatering properties of digested biosolids, and assessed the relationship among digestion, dewatering properties, and characteristics of thermophilically digested biosolids. The experimental work used batch-operated, bench-scale aerobic sludge digesters. Dewaterability was measured as Capillary Suction Time (CST). The study found that feed sludge composition significantly affected dewaterability of digested sludge. Higher percentage of the secondary sludge in the feed sludge corresponded to more significant deterioration in dewaterability. The effect of thermophilic digestion temperatures on dewaterabilty was rapid, occurred within 3-hour of digestion, indicting a heat shock effect, rather than a microbiological effect. When a high shear was applied to the sludge in digesters, it resulted In a significant deterioration in dewaterability in the digested sludge. It appears there was a strong correlation between dewaterability and extracellular biopolymers. Enzymes (protease) treatment confirmed that role of extracellular proteins in affecting the dewatering properties of thermophilic biosolids, also revealed the complex nature of biopolymers' effect on dewaterability. Such effects might be due to protein-polysaccharides interactions, hydrogen bonding, or hydrophilic and hydrophobic

Rumen undegradable protein (RUP) and its intestinal digestibility after steam flaking of cereal grains

DEFF Research Database (Denmark)

Chrenková, M; Formelová, Z; Ceresnáková, Z

2018-01-01

While it is known that heat treatment of cereal grains generally improves the nutritional value for ruminants, simultaneous information on rumen degradability and intestinal digestibility of the rumen by-pass is scarce, especially for non-starch constituents. The effect of steam flaking at 90°C...... flaking on chemical composition of cereal grains (crude protein, acid detergent fibre, neutral detergent fibre, and starch) were observed. The protein fractions that are relevant to rumen degradability were significantly influenced by the steam flaking: the non-protein nitrogen fraction (A) was reduced (P...... hand, steam flaking markedly increased buffer insoluble but neutral detergent soluble protein fraction (B2) by 15–25% for all three cereal grains, whereas effects on B3 fraction were not significant. Steam flaking was also associated with an increase of the rumen undegradable protein fraction (C...

The effect of dietary protein on reproduction in the mare. I. The composition and evaluation of the digestibility of dietary protein from different sources

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F.E. Van Niekerk

1997-07-01

Full Text Available Four rations that differed in their crude protein and essential amino-acid content were compiled. Digestibility of the crude protein and essential amino-acid contents were determined biologically in a feeding trial using 4 Anglo-Arab stallions. Their respective daily diets were: Diet 1: 2 kg cubes, 5 kg tef hay (Eragrostis tef; Diet 2: 2 kg cubes, 5 kg lucerne hay (Medicago sativa; Diet 3: 2 kg cubes, 5 kg tef hay, 200 g fishmeal; Diet 4: 2 kg cubes, 5 kg lucerne hay, 200 g fishmeal. The concentrations of the amino-acids threonine, iso-leucine, leucine and arginine were increased in the total ration when lucerne hay replaced the tef hay while fishmeal supplementation increased the methionine and lysine contents, which provided a wide range of concentrations of digestible amino-acids in each of the 4 rations.

Effect of Digestible Protein and Sulfur Amino Acids in Starter Diet on Performance and Small Intestinal (Jejunum Morphology of Broilers

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Avisa Akhavan khaleghi

2016-04-01

Full Text Available Introduction Protein is an essential constituent of all tissues of animal body and has major effect on growth performance of the bird. A better understanding of the nutritional requirements of amino acids allows a more precise nutrition, offering the possibility for the formulator to optimize the requirement of at least minimum levels of crude protein by essential amino acids requirements, generating better result and lower costs for the producer. Methionine + Cystine (total sulfur amino acid = TSSA perform a number of functions in enzyme reactions and protein synthesis. Methionine is an essential amino acid for poultry and has an important role as a precursor of Cystine. Methionine is usually the first limiting amino acid in most of the practical diets for broiler chicken. The efficiency of utilization of dietary nutrients partly depends on the development of the gastro intestinal tract. Material and methods A 2×3 factorial arrangement in a CRD experiment was conducted to study the effect of digestible protein (DP and sulfur amino acids (DSAA during the starter period on performance and small intestinal (jejunum villous morphology. A total number of 300 day-old Ross 308 male broiler chicks were randomly distributed to 30 groups with 10 chicks each. Treatments consisted of two dietary levels of DP (19.5 and 21.5% and three dietary levels of DSAA (0.94, 1.02 and 1.1% that were fed for 10 days. For Each group and treatment, Feed Intake (FI, Weight Gain (WG and Feed Conversion Ratio (FCR were calculated and all the data were statistically analyzed by the SAS software. Results and Discussions The effects of different levels of protein and digestible sulfur amino acids on the mean feed intake, feed conversion ratio and daily weight gain are shown in the Table 3. Increase in the percentage of digestible sulfur amino acids, increased the levels of feed intake and feed conversion ratio in the starter period but, had no effect on the WG. Adding the DSAA

Struvite Precipitation as a Means of Recovering Nutrients and Mitigating Ammonia Toxicity in a Two-Stage Anaerobic Digester Treating Protein-Rich Feedstocks.

Science.gov (United States)

Wang, Shunli; Hawkins, Gary L; Kiepper, Brian H; Das, Keshav C

2016-08-03

Accumulation of ammonia, measured as total ammonia nitrogen (TAN), a product of protein decomposition in slaughterhouse wastes, inhibits the anaerobic digestion process, reducing digester productivity and leading to failure. Struvite precipitation (SP) is an effective means to remove TAN and enhance the buffering of substrates. Different Mg and P sources were evaluated as reactants in SP in acidogenic digester effluents to reduce its TAN levels. In order to measure impact of TAN removal, a standard biochemical methane potential (BMP) test was conducted to measure methane yield from treatments that had the highest TAN reductions. SP results showed 6 of 9 reagent combinations resulted in greater than 70% TAN removal. The BMP results indicated that SP treatment by adding Mg(OH)₂ and H₃PO₄ resulted in 57.6% nitrogen recovery and 41.7% increase in methane yield relative to the substrate without SP. SP is an effective technology to improve nutrient recovery and methane production from the anaerobic digestion of protein-rich feedstocks.

Effects of nonstructural carbohydrates and protein sources on intake, apparent total tract digestibility, and ruminal metabolism in vivo and in vitro with high-concentrate beef cattle diets.

Science.gov (United States)

Rotger, A; Ferret, A; Calsamiglia, S; Manteca, X

2006-05-01

To investigate the effects of synchronizing nonstructural carbohydrate (NSC) and protein degradation on intake and rumen microbial fermentation, four ruminally fistulated Holstein heifers (BW = 132.3 +/- 1.61 kg) fed high-concentrate diets were assigned to a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments studied in vivo and in vitro with a dual-flow continuous culture system. Two NSC sources (barley and corn) and 2 protein sources [soybean meal (SBM) and sunflower meal (SFM)] differing in their rate and extent of ruminal degradation were combined resulting in a synchronized rapid fermentation diet (barley-SFM), a synchronized slow fermentation diet (corn-SBM), and 2 unsynchronized diets with a rapidly and a slowly fermenting component (barley-SBM, and corn-SFM). In vitro, the fermentation profile was studied at a constant pH of 6.2, and at a variable pH with 12 h at pH 6.4 and 12 h at pH 5.8. Synchronization tended to result in greater true OM digestion (P = 0.072), VFA concentration (P = 0.067), and microbial N flow (P = 0.092) in vitro, but had no effects on in vivo fermentation pattern or on apparent total tract digestibility. The NSC source affected the efficiency of microbial protein synthesis in vitro, tending to be greater (P = 0.07) for barley-based diets, and in vivo, the NSC source tended to affect intake. Dry matter and OM intake tended to be greater (P > or = 0.06) for corn- than barley-based diets. Ammonia N concentration was lower in vitro (P = 0.006) and tended to be lower in vivo (P = 0.07) for corn- than barley-based diets. In vitro, pH could be reduced from 6.4 to 5.8 for 12 h/d without any effect on ruminal fermentation or microbial protein synthesis. In summary, ruminal synchronization seemed to have positive effects on in vitro fermentation, but in vivo recycling of endogenous N or intake differences could compensate for these effects.

Diurnal variation in ruminal pH on the digestibility of highly digestible perennial ryegrass during continuous culture fermentation.

Science.gov (United States)

Wales, W J; Kolver, E S; Thorne, P L; Egan, A R

2004-06-01

Dairy cows grazing high-digestibility pastures exhibit pronounced diurnal variation in ruminal pH, with pH being below values considered optimal for digestion. Using a dual-flow continuous culture system, the hypothesis that minimizing diurnal variation in pH would improve digestion of pasture when pH was low, but not at a higher pH, was tested. Four treatments were imposed, with pH either allowed to exhibit normal diurnal variation around an average pH of 6.1 or 5.6, or maintained at constant pH. Digesta samples were collected during the last 3 d of each of four, 9-d experimental periods. A constant pH at 5.6 compared with a constant pH of 6.1 reduced the digestibility of organic matter (OM), neutral detergent (NDF), and acid detergent fiber (ADF) by 7, 14, and 21%, respectively. When pH was allowed to vary (averaging 5.6), digestion of OM, NDF, and ADF were reduced by 15,30, and 36%, respectively, compared with pH varying at 6.1. There was little difference in digestion parameters when pH was either constant or varied with an average pH of 6.1. However, when average pH was 5.6, maintaining a constant pH significantly increased digestion of OM, NDF, and ADF by 5, 25, and 24% compared with a pH that exhibited normal diurnal variation. These in vitro results show that gains in digestibility and potential milk production can be made by minimizing diurnal variation in ruminal pH, but only when ruminal pH is low (5.6). However, larger gains in productivity can be achieved by increasing average daily ruminal pH from 5.6 to 6.1.

Níveis de lisina digestível em rações, utilizando-se o conceito de proteína ideal, para suínos machos castrados de alto potencial genético, dos 30 aos 60 kg Dietary digestible lysine requirements, based on the ideal protein concept, for barrows with high genetic potential from 30 to 60 kg

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Márvio Lobão Teixeira de Abreu

2007-02-01

Full Text Available Objetivou-se determinar o efeito de níveis de lisina digestível, utilizando-se o conceito de proteína ideal, sobre o desempenho e as características de carcaça de 40 leitões machos castrados (peso inicial de 30,02 ± 1,38 kg e peso final 60,44 ± 1,81 kg de alto potencial genético para deposição de carne magra. Os animais foram distribuídos em delineamento de blocos ao acaso, com quatro tratamentos, cinco repetições e dois animais por unidade experimental. Os tratamentos consistiram de uma ração basal (18,08% de PB e 3.250 kcal de EM/kg suplementada com L-lisina HCL, resultando em rações com 0,80; 0,90; 1,00 e 1,10% de lisina digestível. As rações foram suplementadas com níveis crescentes de aminoácidos sintéticos, mantendo-se constantes as relações entre os níveis desses aminoácidos essenciais e os de lisina, com base na digestibilidade verdadeira. Não houve efeito dos tratamentos sobre o consumo de ração, o ganho de peso diário e a concentração de uréia no plasma dos animais. Observou-se comportamento linear da conversão alimentar, que melhorou, e do consumo de lisina digestível diário, que aumentou em função dos níveis de lisina digestível da ração. Os tratamentos não influenciaram as porcentagens de água, proteína e gordura e a deposição de gordura na carcaça dos animais. Os níveis de lisina digestível afetaram de forma linear crescente a deposição de proteína na carcaça. O nível de 1,10% de lisina digestível, correspondente a um consumo de lisina digestível de 21,94 g/dia (3,43 g de Lis/Mcal de EM proporcionou os melhores resultados de desempenho e características de carcaça de suínos machos castrados de alto potencial genético dos 30 aos 60 kg.The effect of increasing dietary digestible lysine levels, based on the ideal protein concept, on performance and carcass characteristics of forty barrows with high genetic potential for lean gain averaging initial and final body weights of

Apparent total tract macronutrient digestibility, fecal characteristics, and fecal fermentative end-product concentrations of healthy adult dogs fed bioprocessed soy protein.

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Beloshapka, A N; de Godoy, M R C; Detweiler, K B; Newcomb, M; Ellegård, K H; Fahey, G C; Swanson, K S

2016-09-01

Animal proteins are commonly used in extruded dog foods. Plant-based proteins have a more consistent nutrient profile than animal sources but may contain antinutritional factors, including trypsin inhibitors and oligosaccharides. Bioprocessed soy protein (SP; HP-300; Hamlet Protein, Inc., Findlay, OH) is a processed soy-based product with low antinutritional factor concentrations and high protein quality. The objective was to evaluate the effects of SP on apparent total tract macronutrient digestibility, fecal characteristics, and fecal fermentative end products. Furthermore, this study aimed to identify if SP can be a replacement for poultry byproduct meal (PBPM) in dog food and determine if there are practical limits to its use. Three palatability experiments were conducted to evaluate 1) 0 vs. 12% SP, 2) 0 vs. 48% SP, and 3) 12 vs. 48% SP. For digestibility, 48 healthy adult Beagle dogs (20 females and 28 males; 3.4 yr mean age and 10.0 kg mean BW) were randomly allotted to 1 of 6 dietary treatments, 0 (control), 4, 8, 12, 24, and 48% SP, in a completely randomized design. All diets were formulated to meet Association of American Feed Control Officials nutrient profiles and contained approximately 30% CP and 16% fat. The treatment period consisted of a 10-d diet adaptation phase followed by a 4-d fresh and total fecal collection phase. The palatability results suggest that of the 3 inclusion levels tested (0, 12, or 48% SP), the best inclusion of SP is 12%, which was preferred over 0 and 48% SP. Digestibility and fecal data were evaluated for linear and quadratic effects using SAS. Stool output (on both an as-is and a DM basis) did not differ from the control except for the 48% SP treatment ( dogs fed 24 and 48% SP compared with the control. Conversely, branched-chain fatty acid concentrations were lower ( dogs fed 8 to 48% SP compared with the control. These data suggest that SP is a suitable replacement for PBPM in dog diets up to a 24% inclusion level.

Influence of the inclusion of cooked cereals and pea starch in diets based on soy or pea protein concentrate on nutrient digestibility and performance of young pigs.

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Parera, N; Lázaro, R P; Serrano, M P; Valencia, D G; Mateos, G G

2010-02-01

An experiment was conducted to compare different dietary vegetable sources of starch and protein on the coefficient of apparent total tract digestibility (CATTD) of energy and nutrients and performance of piglets from 29 to 60 d of age. The experiment was completely randomized with 6 treatments arranged factorially with 3 sources of starch (cooked-flaked corn, cooked-flaked rice, and pea starch) and 2 sources of protein [soy protein concentrate (SPC) and pea protein concentrate (PPC)]. The pea starch and the PPC used were obtained by dehulling and grinding pea seeds to a mean particle size of 30 microm. Each treatment was replicated 6 times (6 pigs per pen). For the entire experiment, piglets fed cooked rice had greater ADG than piglets fed pea starch with piglets fed cooked corn being intermediate (471, 403, and 430 g/d, respectively; P Protein source did not have any effect on piglet performance. The CATTD of DM, OM, and GE were greater (P pea starch being intermediate. Crude protein digestibility was not affected by source of starch but was greater for the diets based on SPC than for diets based on PPC (0.836 vs. 0.821; P Protein source did not affect the digestibility of any of the other dietary components. It is concluded that cooked rice is an energy source of choice in diets for young pigs. The inclusion of PPC in the diet reduced protein digestibility but had no effects on energy digestibility or piglet performance. Therefore, the finely ground starch and protein fractions of peas can be used in substitution of cooked corn or SPC, respectively, in diets for young pigs.

Ruminally undegradable protein content and digestibility for forages using the mobile bag in situ technique.

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Buckner, C D; Klopfenstein, T J; Rolfe, K M; Griffin, W A; Lamothe, M J; Watson, A K; MacDonald, J C; Schacht, W H; Schroeder, P

2013-06-01

Four experiments were conducted to evaluate RUP content and digestibility for smooth bromegrass, subirrigated meadow, upland native range, and warm-season grasses. Samples were collected from esophageally cannulated cows or ruminally cannulated steers. Forages were ruminally incubated in in situ bags for durations of time based on 75% of total mean retention time, which was based on IVDMD and rate of passage calculations. One-half of the bags were duodenally incubated and excreted in the feces, and NDIN was analyzed on all bags for RUP calculations. Crude protein was numerically greater early in the growing cycle for grasses compared with later as grasses matured (P ≤ 0.32). The RUP was 13.3%, 13.3%, and 19.7% of CP for smooth bromegrass, subirrigated meadow, and upland native range, respectively. These values tended to be lower early in the growth cycle and increased (linear P ≤ 0.13) as forages matured for warm-season grasses and subirrigated meadows. Because both CP and RUP content change throughout the growing season, expressing RUP as a percentage of DM gives more consistent averages compared with RUP as a percentage of CP. Coefficient of variation values for RUP as a percentage of DM averaged 0.21 over all 4 experiments compared with 0.26 for RUP as a percentage of CP. Average RUP as a percentage of DM was 2.03%, 1.53%, and 1.94% for smooth bromegrass, subirrigated meadow, and upland native range, respectively. Total tract indigestible protein (TTIDP) linearly increased with maturity for subirrigated meadow samples (P RUP varied considerably, ranging from 25% to 60%. Subirrigated meadow, native range, and smooth bromegrass samples tended to have linear decreases (P ≤ 0.11) in RUP digestibility throughout the growing season. The amount of digested RUP was fairly consistent across experiments and averages for smooth bromegrass, subirrigated meadow, and upland native range were 0.92%, 0.64%, and 0.49% of DM, respectively. Warm-season grasses in Exp. 2 had

Reducing the cost of semi-automated in-gel tryptic digestion and GeLC sample preparation for high-throughput proteomics.

Science.gov (United States)

Ruelcke, Jayde E; Loo, Dorothy; Hill, Michelle M

2016-10-21

Peptide generation by trypsin digestion is typically the first step in mass spectrometry-based proteomics experiments, including 'bottom-up' discovery and targeted proteomics using multiple reaction monitoring. Manual tryptic digest and the subsequent clean-up steps can add variability even before the sample reaches the analytical platform. While specialized filter plates and tips have been designed for automated sample processing, the specialty reagents required may not be accessible or feasible due to their high cost. Here, we report a lower-cost semi-automated protocol for in-gel digestion and GeLC using standard 96-well microplates. Further cost savings were realized by re-using reagent tips with optimized sample ordering. To evaluate the methodology, we compared a simple mixture of 7 proteins and a complex cell-lysate sample. The results across three replicates showed that our semi-automated protocol had performance equal to or better than a manual in-gel digestion with respect to replicate variability and level of contamination. In this paper, we also provide the Agilent Bravo method file, which can be adapted to other liquid handlers. The simplicity, reproducibility, and cost-effectiveness of our semi-automated protocol make it ideal for routine in-gel and GeLC sample preparations, as well as high throughput processing of large clinical sample cohorts. Copyright © 2016 Elsevier B.V. All rights reserved.

The adsorption of α-amylase on barley proteins affects the in vitro digestion of starch in barley flour.

Science.gov (United States)

Yu, Wenwen; Zou, Wei; Dhital, Sushil; Wu, Peng; Gidley, Michael J; Fox, Glen P; Gilbert, Robert G

2018-02-15

The conversion of barley starch to sugars is a complex enzymic process. Most previous work concerned the biotechnical aspect of in situ barley enzymes. However, the interactions among the macromolecular substrates and their effects on enzymic catalysis has been little examined. Here, we explore the mechanisms whereby interactions of protein and starch in barley flour affect the kinetics of enzymatic hydrolysis of starch in an in vitro system, using digestion rate data and structural analysis by confocal microscopy. The degradation kinetics of both uncooked barley flour and of purified starches are found to be two-step sequential processes. Barley proteins, especially the water-soluble component, are found to retard the digestion of starch degraded by α-amylase: the enzyme binds with water-insoluble protein and with starch granules, leading to reduced starch hydrolysis. These findings are of potential industrial value in both the brewing and food industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

Níveis de lisina digestível em rações, utilizando-se o conceito de proteína ideal, para suínos machos castrados de alto potencial genético dos 15 aos 30 kg Dietary digestible lysine levels, using the ideal protein concept, for barrows with high genetic potential from 15 to 30 kg

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Márvio Lobão Teixeira de Abreu

2006-06-01

, were used to evaluate the effect of digestible lysine levels, using the ideal protein concept, on the performance and carcass composition. The treatments were composed of a basal diet containing 19.46% crude protein and 3,280 kcal of ME/kg, that were supplemented with different levels of HCl-L-Lysine, resulting in diets with 0.90, 1.00, 1,10, and 1.20% of digestible lysine. The diets were supplemented with increasing levels of synthetic amino acids, resulting in diets with ratios of methionine + cystine, threonine, tryptophan and valine:lysine constant in 60, 60, 19 e 69%, respectively, based on the true digestibility. No treatment effects on feed intake, concentration of plasma urea and percentages of water, protein and fat in the carcass were observed in this trial. However, significant quadratic effects on weight gain and feed:gain ratio with quadractic maximum and minimum of 1.10 and 1.12% of lysine, respectively, were detected. Intake of digestible lysine increased linearly among treatments. The depositions of protein and fat in the carcass answered quadractily with quadratic maxima at 1.12 and 1.08%, respectively. The level of digestible lysine that provided the best results of performance and carcass characteristics of barrows with high genetic potential from 15 to 30 kg was of 1.12% of true digestible lysine, corresponding to a digestible lysine intake of 12.03 g/day (3.42 g of Lys/Mcal of ME.

Influence of In vitro Digestion on Antioxidative Activity of Coconut ...

African Journals Online (AJOL)

Conclusion: CMPHs are high value-added antioxidants and possess a potential ..... side chain groups were expected to be exposed, ..... enzymatic digestion on antioxidant activity of coffee ... yam bean seed (Sphenostylis stenocarpa) protein.

Peptide profiling and the bioactivity character of yogurt in the simulated gastrointestinal digestion.

Science.gov (United States)

Jin, Yan; Yu, Yang; Qi, Yanxia; Wang, Fangjun; Yan, Jiaze; Zou, Hanfa

2016-06-01

This study investigated the relationship between peptide profiles and the bioactivity character of yogurt in simulated gastrointestinal trials. A total of 250, 434 and 466 peptides were identified by LC-MS/MS analyses of yogurt, gastric digest and pancreatic digest. Forty peptides of yogurt survived in gastrointestinal digestion. κ-CN and β-CN contributed the diversity of peptides during the fermentation process and gastrointestinal digestion, respectively. The favorite of κ-CN by lactic acid bacteria complemented gut digestion by hydrolyzing κ-CN, the low abundance milk proteins. The potential bioactivities were evaluated by in vitro ACE and DPP-IV inhibition assays. The ACE inhibition rate of the pancreatic digests was ~4 - and ~2 - fold greater than that of yogurt and the gastric digests. The ACE inhibitory peptides generated during gastrointestinal digestion improved the ACE inhibitory activity of the gastric and pancreatic digests. The DPP-IV inhibition rate of the pancreatic digest was ~6 - and ~3 - fold greater than that of yogurt and the gastric digest. The numbers of potential DPP-IV inhibitory peptides were positively correlated to the DPP-IV inhibitory activity of the gastric and pancreatic digests. The present study describes the characters and bioactivities of peptides from yogurt in a simulated gastrointestinal digestion. The number of peptides identified from yogurt and gastrointestinal digests by LC-MS/MS increased in the simulated gastrointestinal trials. The in vitro ACE and DPP-IV inhibition bioactivities revealed that the bioactivity of yogurt was enhanced during gastrointestinal digestion. The correlation between peptides and bioactivity in vitro indicated that not only the peptides amount but also the proportion of peptides with high bioactivities contributed to increased bioactivity during gastrointestinal digestion. The study of peptides identified from yogurt and digests revealed that the number of released peptides was not determined

Cor a 14, the allergenic 2S albumin from hazelnut, is highly thermostable and resistant to gastrointestinal digestion

Science.gov (United States)

Pfeifer, Sabine; Bublin, Merima; Dubiela, Pawel; Hummel, Karin; Wortmann, Judith; Hofer, Gerhard; Keller, Walter; Radauer, Christian

2015-01-01

Scope Allergens from nuts frequently induce severe allergic reactions in sensitive individuals. The aim of this study was to elucidate the physicochemical characteristics of natural Cor a 14, the 2S albumin from hazelnut. Methods and results Cor a 14 was purified from raw hazelnuts using a combination of precipitation and chromatographic techniques. The protein was analyzed using gel electrophoresis, MS, and far‐UV circular dichroism (CD) analyses. The immunoglobulin E (IgE) binding of native, heat‐treated, and in vitro digested Cor a 14 was studied. We identified two different Cor a 14 isoforms and showed microclipping at the C‐terminus. CD spectra at room temperature showed the typical characteristics of 2S albumins, and temperatures of more than 80°C were required to start unfolding of Cor a 14 demonstrating its high stability to heat treatment. In vitro digestion experiments revealed that Cor a 14 is resistant to proteolytic degradation. Native and heat‐treated protein was recognized by sera from hazelnut allergic patients. However, denaturation of the allergen led to significantly reduced IgE binding. Conclusion We identified two different isoforms of Cor a 14 displaying high stability under heating and gastric and duodenal conditions. Data from IgE‐binding experiments revealed the existence of both, linear and conformational epitopes. PMID:26178695

Digested sludge-derived three-dimensional hierarchical porous carbon for high-performance supercapacitor electrode

Science.gov (United States)

Zhang, Jia-Jia; Fan, Hao-Xiang; Dai, Xiao-Hu; Yuan, Shi-Jie

2018-04-01

Digested sludge, as the main by-product of the sewage sludge anaerobic digestion process, still contains considerable organic compounds. In this protocol, we report a facile method for preparing digested sludge-derived self-doped porous carbon material for high-performance supercapacitor electrodes via a sustainable pyrolysis/activation process. The obtained digested sludge-derived carbon material (HPDSC) exhibits versatile O-, N-doped hierarchical porous framework, high specific surface area (2103.6 m2 g-1) and partial graphitization phase, which can facilitate ion transport, provide more storage sites for electrolyte ions and enhance the conductivity of active electrode materials. The HPDSC-based supercapacitor electrodes show favourable energy storage performance, with a specific capacitance of 245 F g-1 at 1.0 A g-1 in 0.5 M Na2SO4; outstanding cycling stability, with 98.4% capacitance retention after 2000 cycles; and good rate performance (211 F g-1 at 11 A g-1). This work provides a unique self-doped three-dimensional hierarchical porous carbon material with a favourable charge storage capacity and at the same time finds a high value-added and environment-friendly strategy for disposal and recycling of digested sludge.

Oil-in-water emulsions stabilised by cellulose ethers: stability, structure and in vitro digestion.

Science.gov (United States)

Borreani, Jennifer; Espert, María; Salvador, Ana; Sanz, Teresa; Quiles, Amparo; Hernando, Isabel

2017-04-19

The effect of cellulose ethers in oil-in-water emulsions on stability during storage and on texture, microstructure and lipid digestibility during in vitro gastrointestinal digestion was investigated. All the cellulose ether emulsions showed good physical and oxidative stability during storage. In particular, the methylcellulose with high methoxyl substituents (HMC) made it possible to obtain emulsions with high consistency which remained almost unchanged during gastric digestion, and thus could enhance fullness and satiety perceptions at gastric level. Moreover, the HMC emulsion slowed down lipid digestion to a greater extent than a conventional protein emulsion or the emulsions stabilised by the other cellulose ethers. Therefore, HMC emulsions could be used in weight management to increase satiation capacity and decrease lipid digestion.

Effects of Marine Oils, Digested with Human Fluids, on Cellular Viability and Stress Protein Expression in Human Intestinal Caco-2 Cells

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Cecilia Tullberg

2017-11-01

Full Text Available In vitro digestion of marine oils has been reported to promote lipid oxidation, including the formation of reactive aldehydes (e.g., malondialdehyde (MDA and 4-hydroxy-2-hexenal (HHE. We aimed to investigate if human in vitro digestion of supplemental levels of oils from algae, cod liver, and krill, in addition to pure MDA and HHE, affect intestinal Caco-2 cell survival and oxidative stress. Cell viability was not significantly affected by the digests of marine oils or by pure MDA and HHE (0–90 μM. Cellular levels of HSP-70, a chaperone involved in the prevention of stress-induced protein unfolding was significantly decreased (14%, 28%, and 14% of control for algae, cod and krill oil, respectively; p ≤ 0.05. The oxidoreductase thioredoxin-1 (Trx-1 involved in reducing oxidative stress was also lower after incubation with the digested oils (26%, 53%, and 22% of control for algae, cod, and krill oil, respectively; p ≤ 0.001. The aldehydes MDA and HHE did not affect HSP-70 or Trx-1 at low levels (8.3 and 1.4 μM, respectively, whilst a mixture of MDA and HHE lowered Trx-1 at high levels (45 μM, indicating less exposure to oxidative stress. We conclude that human digests of the investigated marine oils and their content of MDA and HHE did not cause a stress response in human intestinal Caco-2 cells.

Biohydrogen production from co-digestion of high carbohydrate containing food waste and combined primary and secondary sewage sludge

International Nuclear Information System (INIS)

Arain, M.; Sahito, R.

2018-01-01

In this paper, FW (Food Waste) and SS (Sewage Sludge) were co-digested for biohydrogen production. After characterization both FW and SS were found as better option for biohydrogen production. FW was rich in carbohydrate containing specially rice, which was added as more than 50% and easily hydrolyzable waste. FW is considered as an auxiliary substrate for biohydrogen production and high availability of carbohydrate in FW makes it an important substrate for the production of biohydrogen. On the contrary, SS was rich in protein and has a high pH buffering capacity, which makes it appropriate for codigestion. Adequate supplementation of inorganic salts, the addition of hydrogen producing inoculums, protein enrichment and pH buffering capacity of SS and carbohydrate content in FW increases the hydrogen production potential. Various experiments were performed by considering different mixing ratios like 90:10, 80:20, 70:30, 60:40 and 50:50 of FW and SS. The 50:50 and 90:10 mixing ratio of FW and SS were found as best among all other co-digested ratios. The maximum specific hydrogen yield 106.7 mL/gVS added was obtained at a waste composition of 50:50 followed by 92.35 mL/gVS added from 90:10 of FW to SS. The optimum pH and temperature for operating this process were in the range of 5.5-6.5 and 35°C. The production of clean energy and waste utilization in anaerobic co-digestion process makes biohydrogen generation a promising and novel approach to fulfilling the increasing energy needs as a substitute for fossil fuels. (author)

Chronic ethanol feeding modulates the synthesis of digestive enzymes

International Nuclear Information System (INIS)

Ponnappa, B.C.; Hoek, J.B.; Rubin, E.

1987-01-01

The effects of chronic ethanol feeding on pancreatic protein synthesis were investigated. Protein synthesis was assessed by studying the rate of incorporation of 3 H-leucine into TCA-precipitable proteins in isolated pancreatic acini from rats. Chronic ethanol ingestion increased the rate of pancreatic protein synthesis by 2-4 fold. The onset of the increase in protein synthesis was detectable two days after ethanol feeding, reached a maximum after 7 days and remained unchanged after 4 months on the ethanol-containing diet. The rate of synthesis of individual digestive enzymes was studied by SDS-PAGE on extracts obtained from purified zymogen granules. Ethanol feeding induced an increase in the rate of synthesis of most of the digestive enzymes; chymotrypsinogen, trypsinogen and an unidentified protein were increased to a greater extent than other digestive enzymes. By contrast, the synthesis of amylase was selectively decreased after ethanol feeding. These results suggest that chronic ethanol ingestion has specific effects on the rate of synthesis of individual digestive enzymes in the exocrine pancreas

Protein-energy supplementation for lambs: feed intake, ingestive behavior, rumen parameters and nutrient digestibility

Directory of Open Access Journals (Sweden)

Pâmila Carolini Gonçalves da Silva

2017-08-01

Full Text Available The study evaluated the effects of dietary protein-energy supplementation on feed intake, ingestive behavior, rumen parameters and nutrient digestibility in lambs. Four castrated lambs with 31.9 kg mean body weight and fistulated rumen were tested. distributed into latin square design (4x4, four treatments were tested over four periods of time: no supplementation (control or with supplementation at 8, 16 and 24 g kg-1 body weight. The supplement (soybean meal, soybean hulls, ground corn and minerals was provided with roughage (Tifton Bermudagrass, Cynodon spp., hay, which was offered ad libitum once a day, at 8h00. In treatments receiving 0 (control, 8, 16 and 24 g kg-1 supplementation, dry matter intake was 685.26, 742.86, 842.51 and 1013.33 g day-1, crude protein intake was 80.18, 95.98, 118.64, 150.14 g day-1 and metabolizable energy intake 1.55, 1.91, 2.31 and 2.98 g day-1, respectively. Treatments receiving the highest supplementation levels spent less time with rumination and feeding and rested for longer (P < 0.05. Protein-energy supplementation level did not affect rumen parameters. Average rumen pH was 6.3 and rumen ammonia nitrogen 165 mg dL-1; both were affected by sampling time. Supplementation levels until 24 g kg-1 BW improves feed intake and nutrient digestibility linearly and changes ingestive behavior, lowering rumination time without affecting rumen parameters.

Struvite Precipitation as a Means of Recovering Nutrients and Mitigating Ammonia Toxicity in a Two-Stage Anaerobic Digester Treating Protein-Rich Feedstocks

Directory of Open Access Journals (Sweden)

Shunli Wang

2016-08-01

Full Text Available Accumulation of ammonia, measured as total ammonia nitrogen (TAN, a product of protein decomposition in slaughterhouse wastes, inhibits the anaerobic digestion process, reducing digester productivity and leading to failure. Struvite precipitation (SP is an effective means to remove TAN and enhance the buffering of substrates. Different Mg and P sources were evaluated as reactants in SP in acidogenic digester effluents to reduce its TAN levels. In order to measure impact of TAN removal, a standard biochemical methane potential (BMP test was conducted to measure methane yield from treatments that had the highest TAN reductions. SP results showed 6 of 9 reagent combinations resulted in greater than 70% TAN removal. The BMP results indicated that SP treatment by adding Mg(OH2 and H3PO4 resulted in 57.6% nitrogen recovery and 41.7% increase in methane yield relative to the substrate without SP. SP is an effective technology to improve nutrient recovery and methane production from the anaerobic digestion of protein-rich feedstocks.

Verteerbaarheid (ileaal en faecaal) van biologisch geteelde eiwitrijke voedergrondstoffen bij varkens = Digestibility (ileal and faecal) of organically-grown protein-rich raw materials in pigs

NARCIS (Netherlands)

Jongbloed, A.W.; Diepen, van J.T.M.

2007-01-01

In this research the ileal digestibility of nitrogen and amino acids and the faecal digestibility of organic matter, nitrogen, fat, non-starch polysaccharides, energy and phosphorus of protein-rich organicallygrown feed raw materials were evaluated in pigs. The products were rapeseed meal expeller,

Níveis de treonina digestível em dietas para fêmeas suínas de alto potencial genético em lactação sob condições de alta temperatura ambiente Digestible threonine levels of high-producing lactating sows maintained under high temperature environment conditions

Directory of Open Access Journals (Sweden)

Charles Kiefer

2007-10-01

.64; 0.67; 0.70 and 0.73% and 13 replications, and each experimental unit was consisted by a female. The temperature inside in the room was of 29.7 ± 2.5°C. There was no effect of digestible threonine levels in the diet on the weight of the sows at weaning. The total and percentage sow weight losses linearly reduced with the increase of digestible threonine level in the diet during the lactation period. Digestible threonine level in the diets influenced fat thickness (FT at weaning, and affected the total and percentage variation of FT. The compositions of fat and corporal protein at weaning were not influenced by digestible threonine levels in the diet. A linear reduction for total and percentage of corporal fat mobilizations was observed as digestible threonine levels increased in the diet. The mobilization of corporal protein, milk production and the interval weaning time-estrus were not influenced by digestible threonine levels in the diet. Digestible threonine leveld in the diet had no effect on intake of diet, of lysine and of digestible energy. However, a linear increase was observed for the intake of digestible threonine as the levels of it increased in the diet. Digestible threonine levels in the diet had not influenced the energy efficiency of the females, the performance of the piglets and the litters. High-producing lactating sows under high temperature environmental conditions require 0.73% of digestible threonine, corresponding to a daily intake of 32.5g and the digestible threonine:digestible lysine ratio of 73%.

Super-atmospheric pressure ionization mass spectrometry and its application to ultrafast online protein digestion analysis.

Science.gov (United States)

Chen, Lee Chuin; Ninomiya, Satoshi; Hiraoka, Kenzo

2016-06-01

Ion source pressure plays a significant role in the process of ionization and the subsequent ion transmission inside a mass spectrometer. Pressurizing the ion source to a gas pressure greater than atmospheric pressure is a relatively new approach that aims to further improve the performance of atmospheric pressure ionization sources. For example, under a super-atmospheric pressure environment, a stable electrospray can be sustained for liquid with high surface tension such as pure water, because of the suppression of electric discharge. Even for nano-electrospray ionization (nano-ESI), which is known to work with aqueous solution, its stability and sensitivity can also be enhanced, particularly in the negative mode when the ion source is pressurized. A brief review on the development of super-atmospheric pressure ion sources, including high-pressure electrospray, field desorption and superheated ESI, and the strategies to interface these ion sources to a mass spectrometer will be given. Using a recent ESI prototype with an operating temperature at 220 °C under 27 atm, we also demonstrate that it is possible to achieve an online Asp-specific protein digestion analysis in which the whole processes of digestion, ionization and MS acquisition could be completed on the order of a few seconds. This method is fast, and the reaction can even be monitored on a near-real-time basis. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Standards for the High School Psychology Course. ERIC Digest.

Science.gov (United States)

Morganett, L. Lee

The latest contribution to the content standards boom that began in the 1990s comes from the American Psychological Association (APA), which recently published "National Standards for the Teaching of High School Psychology." This Digest discusses: (1) the origin and purposes of the project to develop standards for high school psychology…

Changes over lactation in breast milk serum proteins involved in the maturation of immune and digestive system of the infant.

Science.gov (United States)

Zhang, Lina; de Waard, Marita; Verheijen, Hester; Boeren, Sjef; Hageman, Jos A; van Hooijdonk, Toon; Vervoort, Jacques; van Goudoever, Johannes B; Hettinga, Kasper

2016-09-16

To objective of this study was to better understand the biological functions of breast milk proteins in relation to the growth and development of infants over the first six months of life. Breast milk samples from four individual women collected at seven time points in the first six months after delivery were analyzed by filter aided sample preparation and dimethyl labeling combined with liquid chromatography tandem mass spectrometry. A total of 247 and 200 milk serum proteins were identified and quantified, respectively. The milk serum proteome showed a high similarity (80% overlap) on the qualitative level between women and over lactation. The quantitative changes in milk serum proteins were mainly caused by three groups of proteins, enzymes, and transport and immunity proteins. Of these 21 significantly changed proteins, 30% were transport proteins, such as serum albumin and fatty acid binding protein, which are both involved in transporting nutrients to the infant. The decrease of the enzyme bile salt-activated lipase as well as the immunity proteins immunoglobulins and lactoferrin coincide with the gradual maturation of the digestive and immune system of infants. The human milk serum proteome didn't differ qualitatively but it did quantitatively, both between mothers and as lactation advanced. The changes of the breast milk serum proteome over lactation corresponded with the development of the digestive and immune system of infants. Breast milk proteins provide nutrition, but also contribute to healthy development of infants. Despite the previously reported large number of identified breast milk proteins and their changes over lactation, less is known on the changes of these proteins in individual mothers. This study is the first to determine the qualitative and quantitative changes of milk proteome over lactation between individual mothers. The results indicate that the differences in the milk proteome between individual mothers are more related to the

The effect of replacing lactose by starch on protein and fat digestion in milk-fed veal calves

NARCIS (Netherlands)

Pluschke, A.M.; Gilbert, M.S.; Williams, B.A.; Borne, van den J.J.G.C.; Schols, H.A.; Gerrits, W.J.J.

2016-01-01

Replacing dairy components from milk replacer (MR) with vegetable products has been previously associated with decreased protein and fat digestibility in milk-fed calves resulting in lower live weight gain. In this experiment, the major carbohydrate source in MR, lactose, was partly replaced with

Improving off-line accelerated tryptic digestion. Towards fast-lane proteolysis of complex biological samples.

Science.gov (United States)

Vukovic, Jadranka; Loftheim, Håvard; Winther, Bjørn; Reubsaet, J Léon E

2008-06-27

Off-line digestion of proteins using immobilized trypsin beads is studied with respect to the format of the digestion reactor, the digestion conditions, the comparison with in-solution digestion and its use in complex biological samples. The use of the filter vial as the most appropriate digestion reactor enables simple, efficient and easy-to-handle off-line digestion of the proteins on trypsin beads. It was shown that complex proteins like bovine serum albumin (BSA) need much longer time (89 min) and elevated temperature (37 degrees C) to be digested to an acceptable level compared to smaller proteins like cytochrome c (5 min, room temperature). Comparing the BSA digestion using immobilized trypsin beads with conventional in-solution digestion (overnight at 37 degrees C), it was shown that comparable results were obtained with respect to sequence coverage (>90%) and amount of missed cleavages (in both cases around 20 peptides with 1 or 2 missed cleavages were detected). However, the digestion using immobilized trypsin beads was considerable less time consuming. Good reproducibility and signal intensities were obtained for the digestion products of BSA in a complex urine sample. In addition to this, peptide products of proteins typically present in urine were identified.

Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

Science.gov (United States)

Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

2015-01-01

Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

Digestion of polysaccharides, protein and lipids by adult cockerels fed on diets containing a pectic cell-wall material from white lupin (Lupinus albus L.) cotyledon.

Science.gov (United States)

Carré, B; Leclercq, B

1985-11-01

1. The cell-wall material of white lupin (Lupinus albus L.) cotyledon is characterized by low contents of cellulose (47 g/kg) and lignin (17 g/kg) and a high content of pectic substances (710 g/kg). The digestion of lupin cell-wall material by adult cockerels was estimated using gas-liquid chromatographic analyses of alditol acetates derived from polysaccharide sugars. The analyses were performed in the destarched water-insoluble fractions of feed and excreta. Digestibility measurements were carried out using a 3 d balance period including a 2 d feeding period and a 24 h final starvation period. 2. In the first experiment, six animals were given a diet containing 510 g white lupin cotyledon flour/kg which was the only source of protein and cell walls in the diet. The apparent digestibility of cell-wall components was near zero. 3. In the second experiment, three diets were prepared by diluting a fibre-free basal diet (diet A) by a semi-purified cell-wall preparation introduced at two different levels: 100 g/kg (diet B) and 200 g/kg (diet C). The semi-purified cell walls were prepared from the white lupin cotyledon flour used in the first experiment. The true digestibilities of polysaccharides measured in birds given diets B and C were near zero. It is suggested that the measurement of the neutral-detergent fibre (NDF) content according to Van Soest & Wine (1967) is not a suitable procedure for estimating the undigestible fibre content in poultry nutrition as the cell-wall pectic substances are not included in the NDF measurement. 4. Addition of the semi-purified cell-wall preparation (Expt 2) resulted in a slight decrease in the apparent protein digestibility. This decrease might be explained by the addition of undigestible cell-wall protein. 5. Addition of the semi-purified cell-wall preparation (Expt 2) had no effect on the apparent lipid digestibility. 6. The metabolizable energy values of the basal diet fraction of diets B and C were calculated assuming that

Digested sludge-derived three-dimensional hierarchical porous carbon for high-performance supercapacitor electrode.

Science.gov (United States)

Zhang, Jia-Jia; Fan, Hao-Xiang; Dai, Xiao-Hu; Yuan, Shi-Jie

2018-04-01

Digested sludge, as the main by-product of the sewage sludge anaerobic digestion process, still contains considerable organic compounds. In this protocol, we report a facile method for preparing digested sludge-derived self-doped porous carbon material for high-performance supercapacitor electrodes via a sustainable pyrolysis/activation process. The obtained digested sludge-derived carbon material (HPDSC) exhibits versatile O-, N-doped hierarchical porous framework, high specific surface area (2103.6 m 2  g -1 ) and partial graphitization phase, which can facilitate ion transport, provide more storage sites for electrolyte ions and enhance the conductivity of active electrode materials. The HPDSC-based supercapacitor electrodes show favourable energy storage performance, with a specific capacitance of 245 F g -1 at 1.0 A g -1 in 0.5 M Na 2 SO 4 ; outstanding cycling stability, with 98.4% capacitance retention after 2000 cycles; and good rate performance (211 F g -1 at 11 A g -1 ). This work provides a unique self-doped three-dimensional hierarchical porous carbon material with a favourable charge storage capacity and at the same time finds a high value-added and environment-friendly strategy for disposal and recycling of digested sludge.

High-throughput peptide mass fingerprinting and protein macroarray analysis using chemical printing strategies

International Nuclear Information System (INIS)

Sloane, A.J.; Duff, J.L.; Hopwood, F.G.; Wilson, N.L.; Smith, P.E.; Hill, C.J.; Packer, N.H.; Williams, K.L.; Gooley, A.A.; Cole, R.A.; Cooley, P.W.; Wallace, D.B.

2001-01-01

We describe a 'chemical printer' that uses piezoelectric pulsing for rapid and accurate microdispensing of picolitre volumes of fluid for proteomic analysis of 'protein macroarrays'. Unlike positive transfer and pin transfer systems, our printer dispenses fluid in a non-contact process that ensures that the fluid source cannot be contaminated by substrate during a printing event. We demonstrate automated delivery of enzyme and matrix solutions for on-membrane protein digestion and subsequent peptide mass fingerprinting (pmf) analysis directly from the membrane surface using matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). This approach bypasses the more commonly used multi-step procedures, thereby permitting a more rapid procedure for protein identification. We also highlight the advantage of printing different chemistries onto an individual protein spot for multiple microscale analyses. This ability is particularly useful when detailed characterisation of rare and valuable sample is required. Using a combination of PNGase F and trypsin we have mapped sites of N-glycosylation using on-membrane digestion strategies. We also demonstrate the ability to print multiple serum samples in a micro-ELISA format and rapidly screen a protein macroarray of human blood plasma for pathogen-derived antigens. We anticipate that the 'chemical printer' will be a major component of proteomic platforms for high-throughput protein identification and characterisation with widespread applications in biomedical and diagnostic discovery

Influence of different levels of concentrate and ruminally undegraded protein on digestive variables in beef heifers.

Science.gov (United States)

Pina, D S; Valadares Filho, S C; Tedeschi, L O; Barbosa, A M; Valadares, R F D

2009-03-01

This experiment evaluated the effect of 2 levels of diet concentrate (20 and 40% of DM) and 2 levels of ruminally undegraded protein (RUP: 25 and 40% of CP) on nutrient intake, total and partial apparent nutrient digestibility, microbial protein synthesis, and ruminal and physiological variables. Eight Nellore heifers (233 +/- 14 kg of BW) fitted with ruminal, abomasal, and ileal cannulas were used. The animals were held in individual sheltered pens of approximately 15 m(2) and fed twice daily at 0800 and 1600 h for ad libitum intake. Heifers were allocated in two 4 x 4 Latin square designs, containing 8 heifers, 4 experimental periods, and 4 treatments in a 2 x 2 factorial arrangement. All statistical analyses were performed using PROC MIXED of SAS. Titanium dioxide (TiO(2)) and chromic oxide (Cr(2)O(3)) were used to estimate digesta fluxes and fecal excretion. Purine derivative (PD) excretion and abomasal purine bases were used to estimate the microbial N (MN) synthesis. No significant interaction (P > 0.10) between dietary levels of RUP and concentrate was observed. There was no effect of treatment (P = 0.24) on DMI. Both markers led to the same estimates of fecal, abomasal, and ileal DM fluxes, and digestibilities of DM and individual nutrients. Ruminal pH was affected by sampling time (P RUP, whereas a quadratic effect (P RUP. The higher level of dietary concentrate led to greater MN yield regardless of the level of RUP. The MN yield and the efficiency of microbial yield estimated from urinary PD excretion produced greater (P RUP and concentrate were observed for ruminal and digestive parameters. Neither RUP nor concentrate level affected DMI. Titanium dioxide showed to be similar to Cr(2)O(3) as an external marker to measure digestibility and nutrient fluxes in cattle.

The expression of proteins involved in digestion and detoxification are regulated in Helicoverpa armigera to cope up with chlorpyrifos insecticide.

Science.gov (United States)

Dawkar, Vishal V; Chikate, Yojana R; More, Tushar H; Gupta, Vidya S; Giri, Ashok P

2016-02-01

Helicoverpa armigera is a key pest in many vital crops, which is mainly controlled by chemical strategies. To manage this pest is becoming challenging due to its ability and evolution of resistance against insecticides. Further, its subsequent spread on nonhost plant is remarkable in recent times. Hence, decoding resistance mechanism against phytochemicals and synthetic insecticides is a major challenge. The present work describes that the digestion, defense and immunity related enzymes are associated with chlorpyrifos resistance in H. armigera. Proteomic analysis of H. armigera gut tissue upon feeding on chlorpyrifos containing diet (CH) and artificial diet (AD) using nano-liquid chromatography-mass spectrometry identified upregulated 23-proteins in CH fed larvae. Database searches combined with gene ontology analysis revealed that the identified gut proteins engrossed in digestion, proteins crucial for immunity, adaptive responses to stress, and detoxification. Biochemical and quantitative real-time polymerase chain reaction analysis of candidate proteins indicated that insects were struggling to get nutrients and energy in presence of CH, while at the same time endeavoring to metabolize chlorpyrifos. Moreover, we proposed a potential processing pathway of chlorpyrifos in H. armigera gut by examining the metabolites using gas chromatography-mass spectrometry. H. armigera exhibit a range of intriguing behavioral, morphological adaptations and resistance to insecticides by regulating expression of proteins involved in digestion and detoxification mechanisms to cope up with chlorpyrifos. In these contexts, as gut is a rich repository of biological information; profound analysis of gut tissues can give clues of detoxification and resistance mechanism in insects. © 2014 Institute of Zoology, Chinese Academy of Sciences.

Compared with Raw Bovine Meat, Boiling but Not Grilling, Barbecuing, or Roasting Decreases Protein Digestibility without Any Major Consequences for Intestinal Mucosa in Rats, although the Daily Ingestion of Bovine Meat Induces Histologic Modifications in the Colon.

Science.gov (United States)

Oberli, Marion; Lan, Annaïg; Khodorova, Nadezda; Santé-Lhoutellier, Véronique; Walker, Francine; Piedcoq, Julien; Davila, Anne-Marie; Blachier, François; Tomé, Daniel; Fromentin, Gilles; Gaudichon, Claire

2016-08-01

Cooking may impair meat protein digestibility. When undigested proteins are fermented by the colon microbiota, they can generate compounds that potentially are harmful to the mucosa. This study addressed the effects of typical cooking processes and the amount of bovine meat intake on the quantity of undigested proteins entering the colon, as well as their effects on the intestinal mucosa. Male Wistar rats (n = 88) aged 8 wk were fed 11 different diets containing protein as 20% of energy. In 10 diets, bovine meat proteins represented 5% [low-meat diet (LMD)] or 15% [high-meat diet (HMD)] of energy, with the rest as total milk proteins. Meat was raw or cooked according to 4 processes (boiled, barbecued, grilled, or roasted). A meat-free diet contained only milk proteins. After 3 wk, rats ingested a (15)N-labeled meat meal and were killed 6 h later after receiving a (13)C-valine injection. Meat protein digestibility was determined from (15)N enrichments in intestinal contents. Cecal short- and branched-chain fatty acids and hydrogen sulfide were measured. Intestinal tissues were used for the assessment of protein synthesis rates, inflammation, and histopathology. Meat protein digestibility was lower in rats fed boiled meat (94.5% ± 0.281%) than in the other 4 groups (97.5% ± 0.0581%, P HMD) and on myeloperoxidase activity in the proximal colon (HMD > LMD), but not on other outcomes. The ingestion of bovine meat, whatever the cooking process and the intake amount, resulted in discrete histologic modifications of the colon (epithelium abrasion, excessive mucus secretion, and inflammation). Boiling bovine meat at a high temperature (100°C) for a long time (3 h) moderately lowered protein digestibility compared with raw meat and other cooking processes, but did not affect cecal bacterial metabolites related to protein fermentation. The daily ingestion of raw or cooked bovine meat had no marked effect on intestinal tissues, despite some slight histologic modifications

Common Prairie feeds with different soluble and insoluble fractions used for CPM diet formulation in dairy cattle: impact of carbohydrate-protein matrix structure on protein and other primary nutrient digestion.

Science.gov (United States)

Peng, Quanhui; Wang, Zhisheng; Zhang, Xuewei; Yu, Peiqiang

2014-01-01

An experiment was conducted to investigate the relationship of carbohydrates molecular spectral characteristics to rumen degradability of primary nutrients in Prairie feeds in dairy cattle. In total, 12 different types of feeds were selected, each type of feed was from three different source with total 37 samples. Six types of them were energy-sourced feeds and the others were protein-sourced feeds. The carbohydrates molecular spectral intensity of various functional groups were collected using Fourier transform infrared attenuated total reflectance (ATR-FT/IR) spectroscopy. In the in situ study, the results showed that the rumen digestibility and digestible fractions of primary nutrients (DM, OM, NCP, and CP) were significantly different (P<0.05) among the feeds. The spectral bands features were significantly different (P<0.05) among the feeds. Spectral intensities of A_Cell, H_1415 and H_1370 were weakly positively correlated with in situ rumen digestibility and digestible fractions of DM, OM and NCP. Spectral intensities of H_1150, H_1015, A_1, and A_3 were weakly negatively associated with in situ rumen degradation of CP. Spectral intensities of A_1240 and H_1240, mainly associated with cellulosic compounds, were correlated with rumen CP degradation. The multiple regression analysis demonstrated that the spectral intensities of A_3 and H_1415 played the most important role and could be used as a potential tool to predict rumen protein degradation of feeds in dairy cattle. In conclusion, this study showed that the carbohydrates as a whole have an effect on protein rumen degradation, rather than cellulose alone, indicating carbohydrate-protein matrix structure impact protein utilization in dairy cattle. The non-invasive molecular spectral technique (ATR-FT/IR) could be used as a rapid potential tool to predict rumen protein degradation of feedstuffs by using molecular spectral bands intensities in carbohydrate fingerprint region. Copyright © 2013 Elsevier B

Protein Secondary Structures (α-helix and β-sheet) at a Cellular Level and Protein Fractions in Relation to Rumen Degradation Behaviours of Protein: A New Approach

International Nuclear Information System (INIS)

Yu, P.

2007-01-01

Studying the secondary structure of proteins leads to an understanding of the components that make up a whole protein, and such an understanding of the structure of the whole protein is often vital to understanding its digestive behaviour and nutritive value in animals. The main protein secondary structures are the α-helix and β-sheet. The percentage of these two structures in protein secondary structures influences protein nutritive value, quality and digestive behaviour. A high percentage of β-sheet structure may partly cause a low access to gastrointestinal digestive enzymes, which results in a low protein value. The objectives of the present study were to use advanced synchrotron-based Fourier transform IR (S-FTIR) microspectroscopy as a new approach to reveal the molecular chemistry of the protein secondary structures of feed tissues affected by heat-processing within intact tissue at a cellular level, and to quantify protein secondary structures using multicomponent peak modelling Gaussian and Lorentzian methods, in relation to protein digestive behaviours and nutritive value in the rumen, which was determined using the Cornell Net Carbohydrate Protein System. The synchrotron-based molecular chemistry research experiment was performed at the National Synchrotron Light Source at Brookhaven National Laboratory, US Department of Energy. The results showed that, with S-FTIR microspectroscopy, the molecular chemistry, ultrastructural chemical make-up and nutritive characteristics could be revealed at a high ultraspatial resolution (∼10 μm). S-FTIR microspectroscopy revealed that the secondary structure of protein differed between raw and roasted golden flaxseeds in terms of the percentages and ratio of α-helixes and β-sheets in the mid-IR range at the cellular level. By using multicomponent peak modelling, the results show that the roasting reduced (P <0.05) the percentage of α-helixes (from 47.1% to 36.1%: S-FTIR absorption intensity), increased the

Protein Secondary Structures (alpha-helix and beta-sheet) at a Cellular Levle and Protein Fractions in Relation to Rumen Degradation Behaviours of Protein: A New Approach

Energy Technology Data Exchange (ETDEWEB)

Yu,P.

2007-01-01

Studying the secondary structure of proteins leads to an understanding of the components that make up a whole protein, and such an understanding of the structure of the whole protein is often vital to understanding its digestive behaviour and nutritive value in animals. The main protein secondary structures are the {alpha}-helix and {beta}-sheet. The percentage of these two structures in protein secondary structures influences protein nutritive value, quality and digestive behaviour. A high percentage of {beta}-sheet structure may partly cause a low access to gastrointestinal digestive enzymes, which results in a low protein value. The objectives of the present study were to use advanced synchrotron-based Fourier transform IR (S-FTIR) microspectroscopy as a new approach to reveal the molecular chemistry of the protein secondary structures of feed tissues affected by heat-processing within intact tissue at a cellular level, and to quantify protein secondary structures using multicomponent peak modelling Gaussian and Lorentzian methods, in relation to protein digestive behaviours and nutritive value in the rumen, which was determined using the Cornell Net Carbohydrate Protein System. The synchrotron-based molecular chemistry research experiment was performed at the National Synchrotron Light Source at Brookhaven National Laboratory, US Department of Energy. The results showed that, with S-FTIR microspectroscopy, the molecular chemistry, ultrastructural chemical make-up and nutritive characteristics could be revealed at a high ultraspatial resolution ({approx}10 {mu}m). S-FTIR microspectroscopy revealed that the secondary structure of protein differed between raw and roasted golden flaxseeds in terms of the percentages and ratio of {alpha}-helixes and {beta}-sheets in the mid-IR range at the cellular level. By using multicomponent peak modelling, the results show that the roasting reduced (P <0.05) the percentage of {alpha}-helixes (from 47.1% to 36.1%: S

Conservation of the egg envelope digestion mechanism of hatching enzyme in euteleostean fishes.

Science.gov (United States)

Kawaguchi, Mari; Yasumasu, Shigeki; Shimizu, Akio; Sano, Kaori; Iuchi, Ichiro; Nishida, Mutsumi

2010-12-01

We purified two hatching enzymes, namely high choriolytic enzyme (HCE; EC 3.4.24.67) and low choriolytic enzyme (LCE; EC 3.4.24.66), from the hatching liquid of Fundulus heteroclitus, which were named Fundulus HCE (FHCE) and Fundulus LCE (FLCE). FHCE swelled the inner layer of egg envelope, and FLCE completely digested the FHCE-swollen envelope. In addition, we cloned three Fundulus cDNAs orthologous to cDNAs for the medaka precursors of egg envelope subunit proteins (i.e. choriogenins H, H minor and L) from the female liver. Cleavage sites of FHCE and FLCE on egg envelope subunit proteins were determined by comparing the N-terminal amino acid sequences of digests with the sequences deduced from the cDNAs for egg envelope subunit proteins. FHCE and FLCE cleaved different sites of the subunit proteins. FHCE efficiently cleaved the Pro-X-Y repeat regions into tripeptides to dodecapeptides to swell the envelope, whereas FLCE cleaved the inside of the zona pellucida domain, the core structure of egg envelope subunit protein, to completely digest the FHCE-swollen envelope. A comparison showed that the positions of hatching enzyme cleavage sites on egg envelope subunit proteins were strictly conserved between Fundulus and medaka. Finally, we extended such a comparison to three other euteleosts (i.e. three-spined stickleback, spotted halibut and rainbow trout) and found that the egg envelope digestion mechanism was well conserved among them. During evolution, the egg envelope digestion by HCE and LCE orthologs was established in the lineage of euteleosts, and the mechanism is suggested to be conserved. © 2010 The Authors Journal compilation © 2010 FEBS.

Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn

Directory of Open Access Journals (Sweden)

William Franco Carneiro

2017-09-01

Full Text Available The objective was to determine the requirement of digestible protein (DP for Nile tilapia fed with diets based on soybean meal and corn. Two hundred Nile tilapia juveniles, sexually reversed, were used for a trial period of 100 days. The animals were distributed in 20 boxes of 1000 L-1 in a random design with five treatments and four replications, the boxes were connected to a water recirculation system. Five isoenergetic diets were tested with different levels of digestible protein (DP: 20, 25, 30, 35 and 40%. At the end of the experimental period were evaluated the zootechnical performance data. A quadratic effect (p < 0.05 was shown to parameters of final weight, weight gain, final length, fillet yield and visceral fat with the best points that ranged from 28.3 to 29.9% of DP. The largest area of hepatocytes was found to the lowest levels of DP in the diet (20 and 25% compared to the other levels, which were similar. Thus, Nile tilapia has adequate performance for the consumption of diets based on soybean and corn meal and the recommended level is 28.3% of PD in these conditions.

Immunomodulatory potential of a brewers' spent grain protein hydrolysate incorporated into low-fat milk following in vitro gastrointestinal digestion.

Science.gov (United States)

Crowley, Damian; O'Callaghan, Yvonne; McCarthy, Aoife; Connolly, Alan; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

2015-01-01

Brewers' spent grain (BSG) protein rich fraction was previously hydrolysed using Alcalase (U) and three additional fractions were prepared by membrane fractionation; a 5-kDa retentate (U > 5), a 5-kDa permeate (U milk, subjected to simulated gastrointestinal digestion (SGID) and their anti-inflammatory potential was investigated. The digestates caused a significant reduction (p RAW 264.7 cells. IL-2 and interferon-γ (IFN-γ) production in stimulated Jurkat T cells and IL-1β and tumor necrosis factor-α (TNF-α) production in stimulated RAW 264.7 cells were not affected in the presence of the digestates. Results show that a SGID milk product supplemented with BSG hydrolysate and its associated ultrafiltered fractions can confer anti-inflammatory effects in Jurkat T cells.

Multi-allergen quantification of fining-related egg and milk proteins in white wines by high-resolution mass spectrometry.

Science.gov (United States)

Monaci, Linda; Losito, Ilario; De Angelis, Elisabetta; Pilolli, Rosa; Visconti, Angelo

2013-09-15

A method based on High-Resolution Mass Spectrometry was developed for the simultaneous determination of fining agents containing potentially allergenic milk (casein) and egg-white (lysozyme and ovalbumin) proteins, added to commercial white wines at sub-ppm levels. Selected tryptic peptides were used as quantitative markers. An evaluation of protein digestion yields was also performed by implementing the (15)N-valine-labelled analogues of the best peptide markers identified for αS1 -casein and ovalbumin. The method was based on the combination of ultrafiltration (UF) of protein-containing wines, tryptic digestion of the dialyzed wine extracts and liquid chromatography/high resolution mass spectrometry (LC/HRMS) analysis of tryptic digests. Peptides providing the most intense electrospray ionization (ESI)-MS response were chosen as quantitative markers of the proteins under investigation. Six-point calibrations were performed by adding caseinate and egg-white powder in the concentration range between 0.25 and 10 µg/mL, to an allergen-free white wine. The following three peptide markers, LTEWTSSNVMEER, GGLEPINFQTAADQAR and ELINSWVESQTNGIIR, were highlighted as best markers for ovalbumin, while GTDVQAWIR and NTDGSTDYGILQINSR for lysozyme and YLGYLEQLLR, GPFPIIV and FFVAPFPEVFGK for caseinate. Limits of detection (LODs) ranged from 0.4 to 1.1 µg/mL. The developed method is suited for assessing the contemporary presence of allergenic milk and egg proteins characterizing egg white and caseinate, fining agents typically employed for wine clarification. The LODs of the method enable the detection of sub-ppm concentrations of residual fining agents, that could represent a potential risk for allergic consumers. Copyright © 2013 John Wiley & Sons, Ltd.

Digestibility and IgE-Binding of Glycosylated Codfish Parvalbumin

Science.gov (United States)

de Jongh, Harmen H. J.; Robles, Carlos López; Nordlee, Julie A.; Lee, Poi-Wah; Baumert, Joseph L.; Hamilton, Robert G.; Taylor, Steve L.; Koppelman, Stef J.

2013-01-01

Food-processing conditions may alter the allergenicity of food proteins by different means. In this study, the effect of the glycosylation as a result of thermal treatment on the digestibility and IgE-binding of codfish parvalbumin is investigated. Native and glycosylated parvalbumins were digested with pepsin at various conditions relevant for the gastrointestinal tract. Intact proteins and peptides were analysed for apparent molecular weight and IgE-binding. Glycosylation did not substantially affect the digestion. Although the peptides resulting from digestion were relatively large (3 and 4 kDa), the IgE-binding was strongly diminished. However, the glycosylated parvalbumin had a strong propensity to form dimers and tetramers, and these multimers bound IgE intensely, suggesting stronger IgE-binding than monomeric parvalbumin. We conclude that glycosylation of codfish parvalbumin does not affect the digestibility of parvalbumin and that the peptides resulting from this digestion show low IgE-binding, regardless of glycosylation. Glycosylation of parvalbumin leads to the formation of higher order structures that are more potent IgE binders than native, monomeric parvalbumin. Therefore, food-processing conditions applied to fish allergen can potentially lead to increased allergenicity, even while the protein's digestibility is not affected by such processing. PMID:23878817

Extraction and identification of α-amylase inhibitor peptides from Nephelium lappacheum and Nephelium mutabile seed protein using gastro-digestive enzymes.

Science.gov (United States)

Evaristus, Natashya Anak; Wan Abdullah, Wan Nadiah; Gan, Chee-Yuen

2018-04-01

The potential of N. lappacheum and N. mutabile seed as a source of α-amylase inhibitor peptides was explored based on the local traditional practice of using the seed. Different gastro-digestive enzymes (i.e. pepsin or chymotrypsin) or a sequential digestion were used to extract the peptides. The effects of digestion time and enzyme to substrate (E:S) ratio on the α-amylase inhibitory activity were investigated. Results showed that chymotrypsin was effective in producing the inhibitor peptides from rambutan seed protein at E:S ratio 1:20 for 1 h, whereas pepsin was more effective for pulasan seed protein under the same condition. A total of 20 and 31 novel inhibitor peptides were identified, respectively. These peptides could bind with the subsites of α-amylase (i.e. Trp58, Trp59, Tyr62, Asp96, Arg195, Asp197, Glu233, His299, Asp300, and His305) and formed a sliding barrier that preventing the formation of enzyme/substrate intermediate leading to lower α-amylase activity. Copyright © 2018 Elsevier Inc. All rights reserved.

The Effect of Supplementation Urea and Sulfur in Mixed Cassava Waste Fermented and Soyabean Cake Waste on Digestibility of Protein and Blood Urea Male Sheep

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M Bata

1999-05-01

Full Text Available Eighteen local male sheep were divided into 3 groups I,II and III based on the body weight 18.55±1.27, 15.79±0.67 and 13.14±1.33 kg respectively. Two level urea (2 and 3% and three levels Sulfur (0.02 and 0.3% as treatment, so pattern factorial 2x3 with Randomized Block Design used this experiment. All of the treatment get a same basal feed namely land-grass and concentrate with dry matter ratio 70:30.  The total intake of  dry matter was 4 % of body weight. The concentrate consist of cassava waste fermented  and soyabean cake waste with dry matter  ratio 77.50 : 22.50. Supplementation of urea and sulfur shown not significant interaction, but supplementation urea had effect high significantly (P<0.01 on digestibility of protein and sulfur only had effect significant  (P<0.05 on blood urea. These result had indication that enriched urea in the diet could increase protein digestibility and sulfur level 0.2% could prevent NH3 absorption from rumen. (Animal Production 1(2: 75-81 (1999   Key Words: cassava waste, soyabean cake waste, fermentation, digestibility, urea blood.

Identification of syntrophic acetate-oxidizing bacteria in anaerobic digesters by combined protein-based stable isotope probing and metagenomics

OpenAIRE

Mosbæk, Freya; Kjeldal, Henrik; Mulat, Daniel G; Albertsen, Mads; Ward, Alastair J; Feilberg, Anders; Nielsen, Jeppe L

2016-01-01

Inhibition of anaerobic digestion through accumulation of volatile fatty acids occasionally occurs as the result of unbalanced growth between acidogenic bacteria and methanogens. A fast recovery is a prerequisite for establishing an economical production of biogas. However, very little is known about the microorganisms facilitating this recovery. In this study, we investigated the organisms involved by a novel approach of mapping protein-stable isotope probing (protein-SIP) onto a binned meta...

Potensi “Khimelor” sebagai Tepung Komposit Tinggi Energi Tinggi Protein Berbasis Pangan Lokal (Health Potential of “Khimelor” as Composite Fluor Having Both High Energy and High Protein Level Based on Local Food

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Laksmi Karunia Tanuwijaya

2016-07-01

The use of wheat flour as the basic ingredients of food products for high energy high protein diet is considerably high. Soybeans, mung beans, red leaf spinach and moringa leaf is local food sources of nutrients that are potential to be processed into a composite flour substituting wheat flour, which can be utilized for a variety of food products. The research was aimed to know the influence of proportion of soybeans, mung beans, red leaf spinach and moringa leaf (KhiMeLor on the quality of nutrition, protein and organoleptik quality of composite flour. This was experimental research with a complete random design. The treatment were several composition mixtures of wheat and composite flour, consisting of soybean, mung bean, red leaf spinach and moringa leaf P0 (100% : 0%; P1 (75% : 25%; P2 (50% : 50%; P3 (25% : 75%; P4 (0% : 100%. The content of carbohydrate, protein and fat was analyzed using proximate analysis. The quality of protein was examined from limiting amino acid and protein digestibility score. The sensory test was used to examine the costumer acceptance on sensory parameters. Statistical analysis used One Way Anova which  showed that substitution of  soy bean, mung bean,  moringaleaf and red spinach significantly (p=0,000 increases protein level. The limiting amino acid of P0,P1 and P2 was Lysine, but P3 and P4 was methionine. Protein digestibility of composite fluor was less than P0 (96%. The result of sensory evaluation showed that there was significant difference in aroma (p=0,000 and texture (p=0,029 which decreases as there is an increase of proportion composite flour. The conclusion was different proportion of soy bean, mung bean, moringa leaf and red spinach  influences the nutrition quality and sensory evaluation of composite flour. Keyword : composite flour, local food, KHiMelor

Chemically modified, immobilized trypsin reactor with improved digestion efficiency

NARCIS (Netherlands)

Freije, J.R.; Mulder, P.P.; Werkman, W.; Rieux, L.; Niederlander, H.A G; Verpoorte, Sabeth; Bischoff, Rainer

2005-01-01

Tryptic digestion followed by identification using mass spectrometry is an important step in many proteomic studies. Here, we describe the preparation of immobilized, acetylated trypsin for enhanced digestion efficacy in integrated protein analysis platforms. Complete digestion of cytochrome c was

Rumen Degradability and Post-ruminal Digestion of Dry Matter, Nitrogen and Amino Acids of Three Protein Supplements.

Science.gov (United States)

Gao, Wei; Chen, Aodong; Zhang, Bowen; Kong, Ping; Liu, Chenli; Zhao, Jie

2015-04-01

This study evaluated the in situ ruminal degradability, and subsequent small intestinal digestibility (SID) of dry matter, crude protein (CP), and amino acids (AA) of cottonseed meal (CSM), sunflower seed meal (SFSM) and distillers dried grains with solubles (DDGS) by using the modified three-step in vitro procedure. The ruminal degradability and subsequent SID of AA in rumen-undegradable protein (RUP-AA) varied among three protein supplements. The result show that the effective degradability of DM for SFSM, CSM, and DDGS was 60.8%, 56.4%, and 41.0% and their ruminal fermentable organic matter was 60.0%, 55.9%, and 39.9%, respectively. The ruminal degradable protein (RDP) content in CP for SFSM, CSM, and DDGS was 68.3%, 39.0%, and 32.9%, respectively, at the ruminal solid passage rate of 1.84%/h. The SFSM is a good source of RDP for rumen micro-organisms; however, the SID of RUP of SFSM was lower. The DDGS and CSM are good sources of RUP for lambs to digest in the small intestine to complement ruminal microbial AA of growing lambs. Individual RUP-AA from each protein source was selectively removed by the rumen micro-organisms, especially for Trp, Arg, His, and Lys (p<0.01). The SID of individual RUP-AA was different within specific RUP origin (p<0.01). Limiting amino acid was Leu for RUP of CSM and Lys for both RUP of SFSM and DDGS, respectively. Therefore, different protein supplements with specific limitations should be selected and combined carefully in growing lambs ration to optimize AA balance.

Rheostatic control of tryptic digestion in a microscale fluidic system

International Nuclear Information System (INIS)

Percy, Andrew J.; Schriemer, David C.

2010-01-01

Integrated fluidic systems that unite bottom-up and top-down proteomic approaches have the potential to deliver complete protein characterization. To circumvent fraction collection, as is conducted in current blended approaches, a technique to regulate digestion efficiency in a flow-through system is required. The present study examined the concept of regulating tryptic digestion in an immobilized enzyme reactor (IMER), incorporating mixed solvent systems for digestion acceleration. Using ovalbumin, cytochrome c, and myoglobin as protein standards, we demonstrate that tryptic digestion can be efficiently regulated between complete digestion and no digestion extremes by oscillating between 45 and 0% acetonitrile in the fluid stream. Solvent composition was tuned using programmable solvent waveforms in a closed system consisting of the IMER, a sample delivery stream, a dual gradient pumping system and a mass spectrometer. Operation in this rheostatic digestion mode provides access to novel peptide mass maps (due to substrate unfolding hysteresis) as well as the intact protein, in a reproducible and stable fashion. Although cycle times were on the order of 90 s for testing purposes, we show that regulated digestion is sufficiently rapid to be limited by solvent switching efficiency and kinetics of substrate unfolding/folding. Thus, regulated digestion should be useful in blending bottom-up and top-down proteomics in a single closed fluidic system.

NUTRIENTS DIGESTIBILITY IN Tithonia diversifolia FOLIAGE IN FATTENING RABBITS

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Duilio Nieves

2010-10-01

Full Text Available An experiment was carried out to determine the nutrients digestibility in Tithonia diversifolia foliage in fattening rabbits, 30 animals (1.450 g ± 93.77 initial body weight were distributed according to a completely randomized experimental design in three treatments and ten replicates. The mash diets including 0, 9 and 18 % of tithonia foliage. The dry matter (DMD, organic matter (OMD, crude protein (CPD, neutral detergent fiber (FDND, hemicellulose (HEMD and energy digestibilities (DE were determined using the acid insoluble ash method. The nutrient digestibility in foliage was estimated by the replacing test ingredient method. The DMD, OMD, PCD and HEMD (51.12, 53.45 and 51.25; 51.99, 54.87 and 52.60; 68.57, 60.11 and 64.08, and 44.20, 45.37 and 47.24 % for the three foliage inclusion level, respectively were similar (P>0.05 among diets. The foliage MSD, OMD, PCD, and ED DHEM was 53.80, 55.19, 59.17, 50.00 and 39.18%, while the protein and energy digestible content in tithonia foliage was 109.60 g/kg and 2139.45 kcal/kg. It was concluded that the tithonia foliage has high content of nutrients

[In vivo digestibility of rice genetically modified with CpTI in WZS mini-pig].

Science.gov (United States)

Huang, Qiong; Liu, Haibo; Zhi, Yuan; Gao, Peng; Yy, Zhou; Liu, Shan; Xu, Haibin

2011-11-01

To establish a stable in vivo gastrointestinal model of WZS mini-pig to evaluate the digestibility of rice genetically modified with CpTI (Cowpea Trypsin Inhibitor). METHODS; Three WZS mini-pigs were surgically fitted with O-stomach cannula and T-ileum cannula, and fed with soybean (positive control), CpTI rice and its parental rice meals. The pH value of gastric and intestinal fluid was monitored at different time points. The digested protein products were measured with protein gel electrophoresis at different time points. The pH value of gastric contents was rapidly neutralized by the meal to approximately 6.0, then the pH was reduced by HCl secretion,and it subsequently was increased after 4-6 hours. Compared with rice,the increase or decrease of pH after soybean being fed was later. Soybean protein segments 13kD,17kD, 34kD and 50kD could be highly detected in gastric and intestinal fluid at 5-6h after soybean being introduced. The segment 13kD was digested in intestine. However, no any protein segment was found in the gastric fluid 0.25h after rice being fed. There was no any difference in digestibility between the rice genetically modified with CpTI and its parental rice. It is practicable to establish a in vivo model of WZS mini-pig for digestibility. The digestibility of CpTI rice and its parental rice in gastric and intestinal tract in vivo is equivalent.

Quarterly intrinsic disorder digest (January-February-March, 2014).

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2016-01-01

This is the 5 th issue of the Digested Disorder series that represents a reader's digest of the scientific literature on intrinsically disordered proteins. We continue to use only 2 criteria for inclusion of a paper to this digest: The publication date (a paper should be published within the covered time frame) and the topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the first quarter of 2014; i.e., during the period of January, February, and March of 2014. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included papers a short description is given on its major findings.

Effect of Gastrointestinal Protease Digestion on Bioactivity of Marine Peptides

DEFF Research Database (Denmark)

Jensen, Ida-Johanne; Andersen, Lisa Lystbæk; Ossum, Carlo Gunnar

2014-01-01

executed without concerning subsequent digestion after intake and the aim of this work was hence to investigate how the in vitro antioxidative, antihypertensive and caspase activating activities of peptides are affected by digestion with gastrointestinal (GI) proteases. Five different fish protein...... hydrolysates were chosen to study the effect of in vitro digestion on bioactivity. The protein concentration decreased in all samples during digestion and the molecular weight distribution of the peptides shifted towards lower values. Thus, in vitro digestion with GI proteases resulted in a further degradation...... of the peptides obtained by hydrolysis. The antihypertensive effect increased in all samples after digestion with GI proteases whereas the antioxidative capacity decreased. The effect on the caspase activity depended on the proteases used in the preparation of hydrolysates. In conclusion, the caspase activity...

Transcriptome analysis of the response of Burmese python to digestion.

Science.gov (United States)

Duan, Jinjie; Sanggaard, Kristian Wejse; Schauser, Leif; Lauridsen, Sanne Enok; Enghild, Jan J; Schierup, Mikkel Heide; Wang, Tobias

2017-08-01

Exceptional and extreme feeding behaviour makes the Burmese python (Python bivittatus) an interesting model to study physiological remodelling and metabolic adaptation in response to refeeding after prolonged starvation. In this study, we used transcriptome sequencing of 5 visceral organs during fasting as well as 24 hours and 48 hours after ingestion of a large meal to unravel the postprandial changes in Burmese pythons. We first used the pooled data to perform a de novo assembly of the transcriptome and supplemented this with a proteomic survey of enzymes in the plasma and gastric fluid. We constructed a high-quality transcriptome with 34 423 transcripts, of which 19 713 (57%) were annotated. Among highly expressed genes (fragments per kilo base per million sequenced reads > 100 in 1 tissue), we found that the transition from fasting to digestion was associated with differential expression of 43 genes in the heart, 206 genes in the liver, 114 genes in the stomach, 89 genes in the pancreas, and 158 genes in the intestine. We interrogated the function of these genes to test previous hypotheses on the response to feeding. We also used the transcriptome to identify 314 secreted proteins in the gastric fluid of the python. Digestion was associated with an upregulation of genes related to metabolic processes, and translational changes therefore appear to support the postprandial rise in metabolism. We identify stomach-related proteins from a digesting individual and demonstrate that the sensitivity of modern liquid chromatography/tandem mass spectrometry equipment allows the identification of gastric juice proteins that are present during digestion. © The Authors 2017. Published by Oxford University Press.

Effects of acylation on the functional properties and in vitro trypsin digestibility of red kidney bean (Phaseolus vulgaris L.) protein isolate.

Science.gov (United States)

Yin, Shou-Wei; Tang, Chuan-He; Wen, Qi-Biao; Yang, Xiao-Quan

2009-01-01

The effects of succinylation and acetylation on some functional properties and the in vitro trypsin digestibility of kidney bean protein isolate (KPI) were investigated. The extent of succinylation or acetylation progressively increased from 0% to 96% to 97%, as the anhydride-to-protein ratio increased from 0 to 1 g/g. Polyacrylamide gel electrophoresis (PAGE) and zeta potential analyses indicated that acylation, especially succinylation, considerably increased the net charge and hydrodynamic radius of the proteins in KPI, especially vicilin. Acylation treatment at various anhydride-to-protein ratios (0.05 to 1 g/g) remarkably improved the protein solubility (PS) and emulsifying activity index (EAI) at neutral pH, but the improvement by succinylation was much better than that by acetylation. Succinylation resulted in a marked decrease in mechanical moduli of heat-induced gels of KPI, while the mechanical moduli were, on the contrary, increased by acetylation. Additionally, in vitro trypsin digestibility was improved by the acylation in an anhydride-type and level-dependent manner. The results suggest that the functional properties of KPI could be modulated by the chemical acylation treatment, using succinic or acetic anhydride at appropriate anhydride-to-protein ratios.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. II. Upper digestive tract digestion.

Science.gov (United States)

Gallier, Sophie; Zhu, Xiang Q; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim of this research was to study the effect of milk processing on the in vivo upper digestive tract digestion of milk fat globules. Fasted rats were serially gavaged over a 5h period with cream from raw, pasteurised, or pasteurised and homogenised milk. Only a few intact dietary proteins and peptides were present in the small intestinal digesta. Significantly (Praw (448 mg g(-1) digesta dry matter (DDM)) and homogenised creams (528 mg g(-1) DDM), as compared to pasteurised and homogenised cream (249 mg g(-1) DDM). Microscopy techniques were used to investigate the structural changes during digestion. Liquid-crystalline lamellar phases surrounding the fat globules, fatty acid soap crystals and lipid-mucin interactions were evident in all small intestinal digesta. Overall, the pasteurised and homogenised cream appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of gastrointestinal digestion and heating on the allergenicity of the kiwi allergens Act d 1, actinidin, and Act d 2, a thaumatin-like protein

NARCIS (Netherlands)

Bublin, Merima; Radauer, Christian; Knulst, Andre; Wagner, Stefan; Scheiner, Otto; Mackie, Alan R.; Mills, E. N. Clare; Breiteneder, Heimo

2008-01-01

Kiwifruit is a significant elicitor of allergy both in children and adults. Digestibility of two kiwifruit allergens, actinidin (Act d 1) and thaumatin-like protein (Act d 2), was assessed using an in vitro digestion system that approximates physiological conditions with respect to the passage of

Preparation of polymer brushes grafted graphene oxide by atom transfer radical polymerization as a new support for trypsin immobilization and efficient proteome digestion.

Science.gov (United States)

Guo, Cong; Zhao, Xinyuan; Zhang, Wanjun; Bai, Haihong; Qin, Weijie; Song, Haifeng; Qian, Xiaohong

2017-08-01

Highly efficient protein digestion is one of the key issues in the "bottom-up" strategy-based proteomic studies. Compared with the time-consuming solution-based free protease digestion, immobilized protease digestion offers a promising alternative with obviously improved sample processing throughput. In this study, we proposed a new immobilized protease digestion strategy using two kinds of polymer-grafted graphene oxide (GO) conjugated trypsin. The polymer brush grafted GO was prepared using in situ polymer growth on initiator-functionalized GO using surface-initiated atom transfer radical polymerization (SI-ATRP) and characterized by AFM, TEM, TGA, and XPS. The polymer brush grafted GO supports three-dimensional trypsin immobilization, which not only increases the loading amount but also improves accessibility towards protein substrates. Both of the two types of immobilized trypsin provide 700 times shorter digestion time, while maintaining comparable protein/peptide identification scale compared with that of free trypsin digestion. More interestingly, combined application of the two types of immobilized trypsin with different surface-grafted polymers leads to at least 18.3/31.3% enhancement in protein/peptide identification compared with that obtained by digestion using a single type, indicating the potential of this digestion strategy for deeper proteome coverage using limited mass spectrometer machine hour. We expect these advantages may find valuable application in high throughput clinical proteomic studies, which often involve processing of a large number of samples. Graphical abstract Preparation of polymer brushes grafted and trypsin immobilized graphene oxide and its application in proteome digestion and mass spectrometry identification.

Effects of corn-based diet starch content and neutral detergent fiber source on lactation performance, digestibility, and bacterial protein flow in dairy cows.

Science.gov (United States)

Fredin, S M; Akins, M S; Ferraretto, L F; Shaver, R D

2015-01-01

An experiment was conducted to evaluate the effects of corn-based dietary starch content and source of neutral detergent fiber (NDF) on lactation performance, nutrient digestion, bacterial protein flow, and ruminal parameters in lactating dairy cows. Eight ruminally cannulated multiparous Holstein cows averaging 193±11d in milk were randomly assigned to treatments in a replicated 4×4 Latin square design with 21-d periods. Treatment diets were high corn grain (HCG; 38% corn silage, 19% dry ground corn, and 4% soy hulls), high soy hulls (HSH; 38% corn silage, 11% dry ground corn, and 13% soy hulls), high corn silage (HCS; 50% corn silage, 6% dry ground corn, and 4% soy hulls), and low corn silage (LCS; 29% corn silage, 15% corn, and 19% soy hulls). The HCG, HSH, HCS, and LCS diets contained 29, 23, 24, and 22% starch; 27, 32, 30, and 32% total NDF; and 21, 21, 25, and 17% forage NDF (dry matter basis), respectively. Mean dry matter intake and milk yield were unaffected by treatment. Cows fed LCS had reduced milk fat content compared with HSH and HCS. The concentration of milk urea nitrogen was greater for cows fed HCS compared with the other treatments. Total-tract digestion of NDF was reduced for cows fed the HCG diet. Total-tract starch digestion was increased for cows fed the HSH and HCS compared with HCG and LCS diets. Bacterial protein flow was unaffected by treatment. Ruminal ammonia concentration was reduced in cows fed the HCG and LCS diets compared with the HCS diet. Ruminal propionate increased and the acetate:propionate ratio decreased in cows fed the LCS diet compared with the HCS diet. Ruminal pH was greater for cows fed the HCS diet compared with cows fed the LCS diet. Diet digestibility and performance of mid- to late-lactation cows fed reduced-starch diets by partially replacing corn grain with soy hulls or corn silage was similar to or improved compared with cows fed a normal-starch diet. Copyright © 2015 American Dairy Science Association

Evaluation of an in vitro system to simulate equine foregut digestion and the influence of acidity on protein and fructan degradation in the horse's stomach.

Science.gov (United States)

Strauch, S; Wichert, B; Greef, J M; Hillegeist, D; Zeyner, A; Liesegang, A

2017-06-01

The aim of this study was to improve an in vitro system in order to gather optimized information on the digestion of different forages in the horse's upper gastrointestinal tract. Therefore, foregut digestion of several forages was simulated in vitro (Part 1). The effect of different pH values on in vitro fructan degradation of two selected grasses (Part 2) was tested subsequently. Part 1: We hypothesized that our system produces representative results simulating digestive processes in the upper alimentary tract, but neglects microbial fermentation. In vitro digestion of six forages (grass mixture for horses, grass mixture for cows (GMC), tall fescue, English perennial ryegrass (ER), white clover, lucerne) was performed in two phases with pepsin and pancreatin. The results are consistent with current data from in vivo studies, including a degradation of crude protein and monosaccharides as well as a relative increase in fibres. Interestingly, a loss of fructan was measured in two feedstuffs (ER/GMC: 4.1/4.4% DM fructan before and 0.59/0.00% DM after simulated foregut digestion). Part 2: As fructans are thought not to be fragmented by digestive enzymes, another hypothesis was developed: acidic hydrolysis leads to a degradation of fructans. To evaluate the influence of gastric pH on the digestion of fructan and protein, different pH values (2, 3 and 4) were adjusted in a second series of in vitro foregut digestion trials with ER and GMC. As expected, the highest degradation of protein was seen at the lowest pH (protein in ER/GMC at pH 2: 6.11/8.28% DM and at pH 4: 7.73/10.64% DM), whereas fructan degradation was highest at pH 4 (fructan in ER/GMC at pH 2: 1.63/1.95% DM and at pH 4: 1.31/0.91% DM). We presume that not only acidic hydrolysis but also plant enzymes cause the loss of fructans in an acidic environment. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

High strength sewage treatment in a UASB reactor and an integrated UASB-digester system.

Science.gov (United States)

Mahmoud, Nidal

2008-11-01

The treatment of high strength sewage was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-digester system. The one-stage UASB reactor was operated in Palestine at a hydraulic retention time (HRT) of 10h and at ambient air temperature for a period of more than a year in order to asses the system response to the Mediterranean climatic seasonal temperature fluctuation. Afterwards, the one-stage UASB reactor was modified to a UASB-digester system by incorporating a digester operated at 35 degrees C. The achieved removal efficiencies in the one-stage UASB reactor for total, suspended, colloidal, dissolved and VFA COD were 54, 71, 34, 23%, and -7%, respectively during the first warm six months of the year, and achieved only 32% removal efficiency for COD total over the following cold six months of the year. The modification of the one-stage UASB reactor to a UASB-digester system had remarkably improved the UASB reactor performance as the UASB-digester achieved removal efficiencies for total, suspended, colloidal, dissolved and VFA COD of 72, 74, 74, 62 and 70%. Therefore, the anaerobic treatment of high strength sewage during the hot period in Palestine in a UASB-digester system is very promising.

Effects of corn-based diet starch content and corn particle size on lactation performance, digestibility, and bacterial protein flow in dairy cows.

Science.gov (United States)

Fredin, S M; Ferraretto, L F; Akins, M S; Bertics, S J; Shaver, R D

2015-01-01

An experiment was conducted to determine the effects of dietary starch content in corn-based diets and corn particle size on lactation performance, nutrient digestibility, and bacterial protein flow in dairy cows using the omasal and reticular sampling technique. Eight ruminally cannulated lactating multiparous Holstein cows were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Treatments were fine (FG; mean particle size=552µm) and coarse (CG; 1,270µm) ground dry shelled corn in normal- (NS) and reduced- (RS) starch diets fed as total mixed rations. The NS and RS rations contained 27 and 18% starch (dry matter basis), respectively, and were formulated by partially replacing corn with soy hull pellets. Mean dry matter intake was unaffected by treatment (23.2kg/d). Cows fed NS diets produced 1.9kg/d more milk and 0.06kg/d more milk protein compared with cows fed RS diets. Cows fed NSFG and RSCG diets produced more fat-corrected milk than did cows fed NSCG and RSFG diets. Milk urea concentration was decreased for cows fed NS diets (12.4mg/dL) compared with RS diets (13.5mg/dL). Ruminal digestibility of neutral detergent fiber (NDF; % of NDF intake) determined by the omasal sampling technique was increased in cows fed RS diets compared with NS diets (43.4 vs. 34.9%), and total-tract digestibility of NDF (% of NDF intake) was increased in cows fed RS diets compared with those fed NS diets (50.1 vs. 43.1%). Ruminal digestibility of starch (% of starch intake) determined by the omasal sampling technique was greater in cows fed NS diets compared with those fed RS diets (85.6 vs. 81.6%). Total-tract starch digestion was increased in cows fed RS diets compared with those fed NS diets (96.9 vs. 94.6%) and in cows fed FG diets compared with those fed CG diets (98.0 vs. 93.5%). Bacterial protein flow was unaffected by treatment. The omasal and reticular sampling techniques resulted in similar treatment effects for nutrient flow

Protein quality of insects as potential ingredients for dog and cat foods.

Science.gov (United States)

Bosch, Guido; Zhang, Sheng; Oonincx, Dennis G A B; Hendriks, Wouter H

2014-01-01

Insects have been proposed as a high-quality, efficient and sustainable dietary protein source. The present study evaluated the protein quality of a selection of insect species. Insect substrates were housefly pupae, adult house cricket, yellow mealworm larvae, lesser mealworm larvae, Morio worm larvae, black soldier fly larvae and pupae, six spot roach, death's head cockroach and Argentinean cockroach. Reference substrates were poultry meat meal, fish meal and soyabean meal. Substrates were analysed for DM, N, crude fat, ash and amino acid (AA) contents and for in vitro digestibility of organic matter (OM) and N. The nutrient composition, AA scores as well as in vitro OM and N digestibility varied considerably between insect substrates. For the AA score, the first limiting AA for most substrates was the combined requirement for Met and Cys. The pupae of the housefly and black soldier fly were high in protein and had high AA scores but were less digestible than other insect substrates. The protein content and AA score of house crickets were high and similar to that of fish meal; however, in vitro N digestibility was higher. The cockroaches were relatively high in protein but the indispensable AA contents, AA scores and the in vitro digestibility values were relatively low. In addition to the indices of protein quality, other aspects such as efficiency of conversion of organic side streams, feasibility of mass-production, product safety and pet owner perception are important for future dog and cat food application of insects as alternative protein source.

Energy production from agricultural residues: High methane yields in pilot-scale two-stage anaerobic digestion

International Nuclear Information System (INIS)

Parawira, W.; Read, J.S.; Mattiasson, B.; Bjoernsson, L.

2008-01-01

There is a large, unutilised energy potential in agricultural waste fractions. In this pilot-scale study, the efficiency of a simple two-stage anaerobic digestion process was investigated for stabilisation and biomethanation of solid potato waste and sugar beet leaves, both separately and in co-digestion. A good phase separation between hydrolysis/acidification and methanogenesis was achieved, as indicated by the high carbon dioxide production, high volatile fatty acid concentration and low pH in the acidogenic reactors. Digestion of the individual substrates gave gross energy yields of 2.1-3.4 kWh/kg VS in the form of methane. Co-digestion, however, gave up to 60% higher methane yield, indicating that co-digestion resulted in improved methane production due to the positive synergism established in the digestion liquor. The integrity of the methane filters (MFs) was maintained throughout the period of operation, producing biogas with 60-78% methane content. A stable effluent pH showed that the methanogenic reactors had good ability to withstand the variations in load and volatile fatty acid concentrations that occurred in the two-stage process. The results of this pilot-scale study show that the two-stage anaerobic digestion system is suitable for effective conversion of semi-solid agricultural residues as potato waste and sugar beet leaves

Slowly digestible properties of lotus seed starch-glycerine monostearin complexes formed by high pressure homogenization.

Science.gov (United States)

Chen, Bingyan; Jia, Xiangze; Miao, Song; Zeng, Shaoxiao; Guo, Zebin; Zhang, Yi; Zheng, Baodong

2018-06-30

Starch-lipid complexes were prepared using lotus seed starch (LS) and glycerin monostearate (GMS) via a high-pressure homogenization process, and the effect of high pressure homogenization (HPH) on the slow digestion properties of LS-GMS was investigated. The digestion profiles showed HPH treatment reduced the digestive rate of LS-GMS, and the extent of this change was dependent on homogenized pressure. Scanning electron microscopy displayed HPH treatment change the morphology of LS-GMS, with high pressure producing more compact block-shape structure to resist enzyme digestion. The results of Gel-permeation chromatography and Small-angle X-ray scattering revealed high homogenization pressure impacted molecular weight distribution and semi-crystalline region of complexes, resulting in the formation of new semi-crystalline with repeat unit distance of 16-18 nm and molecular weight distribution of 2.50-2.80 × 10 5  Da, which displayed strong enzymatic resistance. Differential scanning calorimeter results revealed new semi-crystalline lamellar may originate from type-II complexes that exhibited a high transition temperature. Copyright © 2018 Elsevier Ltd. All rights reserved.

Rumen Degradability and Post-ruminal Digestion of Dry Matter, Nitrogen and Amino Acids of Three Protein Supplements

Directory of Open Access Journals (Sweden)

Wei Gao

2015-04-01

Full Text Available This study evaluated the in situ ruminal degradability, and subsequent small intestinal digestibility (SID of dry matter, crude protein (CP, and amino acids (AA of cottonseed meal (CSM, sunflower seed meal (SFSM and distillers dried grains with solubles (DDGS by using the modified three-step in vitro procedure. The ruminal degradability and subsequent SID of AA in rumen-undegradable protein (RUP-AA varied among three protein supplements. The result show that the effective degradability of DM for SFSM, CSM, and DDGS was 60.8%, 56.4%, and 41.0% and their ruminal fermentable organic matter was 60.0%, 55.9%, and 39.9%, respectively. The ruminal degradable protein (RDP content in CP for SFSM, CSM, and DDGS was 68.3%, 39.0%, and 32.9%, respectively, at the ruminal solid passage rate of 1.84%/h. The SFSM is a good source of RDP for rumen micro-organisms; however, the SID of RUP of SFSM was lower. The DDGS and CSM are good sources of RUP for lambs to digest in the small intestine to complement ruminal microbial AA of growing lambs. Individual RUP-AA from each protein source was selectively removed by the rumen micro-organisms, especially for Trp, Arg, His, and Lys (p<0.01. The SID of individual RUP-AA was different within specific RUP origin (p<0.01. Limiting amino acid was Leu for RUP of CSM and Lys for both RUP of SFSM and DDGS, respectively. Therefore, different protein supplements with specific limitations should be selected and combined carefully in growing lambs ration to optimize AA balance.

A high-throughput assay for quantifying appetite and digestive dynamics

Science.gov (United States)

Guggiana-Nilo, Drago; Soucy, Edward; Song, Erin Yue; Lei Wee, Caroline; Engert, Florian

2015-01-01

Food intake and digestion are vital functions, and their dysregulation is fundamental for many human diseases. Current methods do not support their dynamic quantification on large scales in unrestrained vertebrates. Here, we combine an infrared macroscope with fluorescently labeled food to quantify feeding behavior and intestinal nutrient metabolism with high temporal resolution, sensitivity, and throughput in naturally behaving zebrafish larvae. Using this method and rate-based modeling, we demonstrate that zebrafish larvae match nutrient intake to their bodily demand and that larvae adjust their digestion rate, according to the ingested meal size. Such adaptive feedback mechanisms make this model system amenable to identify potential chemical modulators. As proof of concept, we demonstrate that nicotine, l-lysine, ghrelin, and insulin have analogous impact on food intake as in mammals. Consequently, the method presented here will promote large-scale translational research of food intake and digestive function in a naturally behaving vertebrate. PMID:26108871

Iron uptake by Caco-2 cells following in vitro digestion: effects of heat treatments of pork meat and pH of the digests.

Science.gov (United States)

Sørensen, Anne D; Bukhave, Klaus

2010-10-01

The present in vitro studies report on iron uptake by Caco-2 cells from pepsin and pepsin+pancreatin-digested pork meat proteins at pH values between 4.6 and 7 mimicking conditions in the duodenum and the proximal jejunum, respectively. Heat treatment of the pork meat resulted in increased iron uptake from pepsin-digested samples to Caco-2 cells at pH 4.6. The major enhancing effects on iron uptake by Caco-2 cells were observed after pepsin digestion in the pH range 4.6-6.0, whereas the pepsin+pancreatin-digested samples resulted in negligible iron uptake in Caco-2 cells at pH 7. Thus, the results emphasize the importance of separating pepsin-digested and pepsin+pancreatin-digested proteins during in vitro studies on iron availability. Furthermore, the present results showed the pH dependency of iron uptake anticipated. The enhancing effect of ascorbic acid was verified by increased iron uptake from pepsin-digested pork meat samples at pH 4.6, while no effect of ascorbic acid was observed at pH 7 in pepsin+pancreatin-digested samples. Copyright © 2010 Elsevier GmbH. All rights reserved.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. I. Gastric digestion.

Science.gov (United States)

Gallier, Sophie; Cui, Jack; Olson, Trent D; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim was to study the in vivo gastric digestion of fat globules in bovine cream from raw, pasteurised or pasteurised and homogenised milk. Fasted rats were gavaged once and chyme samples were collected after 30, 120 and 180 min post-gavage. Proteins from raw (RC) and pasteurised (PC) creams appeared to be digested faster and to a greater extent. Free fatty acids (FAs) increased throughout the 3h postprandial period. Short and medium chain FAs were released more rapidly than long chain FAs which were hydrolysed to a greater degree from PC. The size of the fat globules of all creams increased in the stomach. Protein aggregates were observed in pasteurised and homogenised cream chyme. Protrusions, probably caused by the accumulation of insoluble lipolytic products, appeared at the surface of the globules in RC and PC chyme. Overall, PC proteins and lipids appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

The effects of the proportions of dietary macronutrients on the digestibility, post-prandial endocrine responses and large intestinal fermentation of carbohydrate in working dogs.

Science.gov (United States)

Hill, S R; Rutherfurd-Markwick, K J; Ravindran, G; Ugarte, C E; Thomas, D G

2009-12-01

To compare the effects of feeding diets varying in the proportions of macronutrients on the digestibility, post-prandial endocrine responses and large intestinal fermentation of carbohydrate in working dogs. The apparent digestibility of two test diets, one comprising low-carbohydrate, high-protein dry biscuits (Diet 1), and one comprising high-carbohydrate, low-protein dry biscuits (Diet 2), fed to 12 adult Harrier Hounds (n=5 female), was determined using the indigestible-marker and total-collection methods. Serial breath samples were collected from each dog before and after feeding, and analysed for concentrations of hydrogen. Concentrations of glucose and insulin in plasma were established from serial blood samples obtained after feeding. The apparent dry matter, protein, fat and energy digestibility of Diet 1 were higher, but the carbohydrate digestibility was lower (pdogs occurred earlier for Diet 1 than Diet 2 (pdogs fed Diet 2 than Diet 1 (pdogs fed Diet 2 compared with those fed Diet 1 (pdogs, including higher apparent nutrient digestibility, slower release of glucose into the bloodstream, and reduced large intestinal fermentation of carbohydrate. A low-carbohydrate, high-protein diet may be beneficial for specific groups of dogs, including working dogs subjected to prolonged bouts of exercise requiring a sustained energy source, or those with diabetes mellitus requiring better glycaemic control.

Extraction of intracellular protein from Chlorella pyrenoidosa using a combination of ethanol soaking, enzyme digest, ultrasonication and homogenization techniques.

Science.gov (United States)

Zhang, Ruilin; Chen, Jian; Zhang, Xuewu

2018-01-01

Due to the rigid cell wall of Chlorella species, it is still challenging to effectively extract significant amounts of protein. Mass methods were used for the extraction of intracellular protein from microalgae with biological, mechanical and chemical approaches. In this study, based on comparison of different extraction methods, a new protocol was established to maximize extract amounts of protein, which was involved in ethanol soaking, enzyme digest, ultrasonication and homogenization techniques. Under the optimized conditions, 72.4% of protein was extracted from the microalgae Chlorella pyrenoidosa, which should contribute to the research and development of Chlorella protein in functional food and medicine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dewaterability of thermophilically digested biosolids: effects of temperature and cellular polymeric substances

International Nuclear Information System (INIS)

Zhou, J.; Mavinic, D.S.; Kelly, H.G.; Ramey, W.D.

2002-01-01

Thermophilic processes digest sludge at high temperatures to produce Class A biosolids.Recent research work revealed that digestion temperature is the predominant factor affecting dewaterability of thermophilic biosolids. This paper presents findings of a laboratory study that investigated how various digestion temperatures affect dewaterability of digested biosolids, studied the phase partition of the substances affecting dewaterability in digested biosolids, and tested the role of cellular polymeric substances in affecting dewaterability.Secondary sludges were digested at 40-70 o C or 22 o C for up to 12 days. Centrate from thermophilically digested biosolids were treated with protease and boiling. This study found that, during the first few hours of digestion, higher temperatures resulted in more rapid and more significant deterioration in dewaterability than lower digestion temperatures. Continued digestion resulted in either improved (60 o C or 70 o C), or unchanged (40 o C or 50 o C), or gradually deteriorated dewaterability (22 o C). The substances affecting dewaterability were primarily located in the liquid phase of thermophilically digested biosolids. Boiling treatment did not result in significant changes in dewaterability. Protease treatment of the liquid phase of thermophilic biosolids improved dewaterability by 13-19%. Such an improvement confirmed the role of proteins in affecting dewaterability. (author)

Starch hydrolysis in autogenerative high pressure digestion: Gelatinisation and saccharification as rate limiting steps

NARCIS (Netherlands)

Lindeboom, R.E.F.; Ding, L.; Weijma, J.; Plugge, C.M.; Lier, van J.B.

2014-01-01

Autogenerative high pressure digestion (AHPD) provides an integrated biogas upgrading technology, capable of producing biogas with a CH4 content exceeding 95% at pressures up to 90 bar. Hydrolysis is generally regarded as the rate-limiting step in the anaerobic digestion of complex organic matter,

Antioxidant activity of camel milk casein before and after in vitro simulated enzymatic digestion

Directory of Open Access Journals (Sweden)

Zeineb Jrad

2014-11-01

Full Text Available The effect of a successive in vitro hydrolysis by pepsin and pancreatin on the free radical scavenging activity of camel milk casein was investigated in order to assess the effect of gastro-intestinal digestion. Hydrolysis of camel casein was controlled by reversed-phase high performance liquid chromatography. Anti-oxidant activity was measured by the 2,2’-azino-bis-(3-ethylbensothiazoline-6- sulfonic acid (ABTS method. The Trolox equivalent antioxidant capacity (TEAC values of camel casein and its hydrolysate were 1.6±0.12 μmol TE/mg protein and 0.25 μmol TE/μmol eq. NH2, respectively. After digestion, the scavenging activity of the casein peptides was more efficient than those reported in the literature regarding digestive hydrolysates of camel milk, colostrum and whey proteins.

Clinical value of Xenopus kinesin-like protein 2 as a prognostic marker in patients with digestive system cancers: a systematic review and meta-analysis.

Science.gov (United States)

Wang, Gang; Wang, Qian; Li, Zhengyan; Liu, Chaoxu; He, Xianli

2018-01-01

Xenopus kinesin-like protein 2 (TPX2) is a microtubule-associated protein that plays an important role in spindle assembly and dynamics. However, the clinical and prognostic value of TPX2 in the digestive system cancers remains unclear. The objective of this review was to evaluate the association of TPX2 expression with disease-free survival (DFS), overall survival (OS), and clinicopathological features of digestive system cancers. The software Stata 12.0 was used to analyze the outcomes, including OS, disease-free survival (DFS), and clinicopathological characteristics. A total of 10 eligible studies with 906 patients were included. Elevated TPX2 expression was significantly associated with poor DFS (pooled hazard ratio [HR] =2.48, 95% confidence interval [CI]: 1.96-3.13) and OS (pooled HR =2.66, 95% CI: 2.04-3.48) of digestive system malignancies. Subgroup analyses showed that cancer type, sample size, study quality, and laboratory detection methods did not alter the significant prognostic value of TPX2. Additionally, TPX2 expression was found to be an independent predictive factor for DFS (HR =2.31, 95% CI: 1.78-3.01). TPX2 expression might be associated with TNM stage and pathological grade in digestive system cancer. In conclusion, TPX2 is an independent prognostic factor for survival of patients with digestive system cancer. Furthermore, its overexpression is associated with TNM stage and pathological grade in digestive system cancer.

The influence of digestibility on the allergenicity of food allergens

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

2012-01-01

potential exist. Resistance to digestion is therefore a test parameter included in the safety assessment of the allergenic potential of novel proteins in genetically modified foods. In recent years, the association between resistance to digestion and allergenic potential has been challenged. When reviewing......Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. What makes a dietary protein a food allergen has not yet been established, though several characteristics have been proposed to be shared by the food allergens. One of the features believed...... existing data from digestibility studies on known food allergens, it becomes evident that food allergens do not necessarily resist digestion. However, the choice of assay conditions, the method used for detection of residual intact protein as well as fragments hereof greatly influences the outcome. Studies...

Standardized ileal digestibility of proteins and amino acids in sesame expeller and soya bean meal in weaning piglets.

Science.gov (United States)

Aguilera, A; Reis de Souza, T C; Mariscal-Landín, G; Escobar, K; Montaño, S; Bernal, M G

2015-08-01

Apparent ileal digestibility (AID) of diets containing sesame expeller (SE) and soya bean meal (SBM) was determined using 15 piglets (Genetiporc(®)), weaned at 17 ± 0.4 days with average body weight of 6.4 ± 0.7 kg (Fertilis 20 × G Performance, Genetiporc(®), PIC México, Querétaro, México). Piglets were randomly assigned to three treatments: (i) a reference diet with casein as the sole protein source; (ii) a mixed diet of casein-SE; and (iii) a mixed diet of casein-SBM. The chemical composition of SE and SBM was determined, and AID and standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AAs) were determined for each protein source. SE contained greater quantities of ether extract, neutral detergent fibre, phytic acid, methionine and arginine than SBM. Lysine and proline contents and trypsin inhibitor activity were higher in SBM than in SE. The AID and SID of CP and AA (except for lysine and proline) were similar in SE and SBM. The AID of lysine and proline was higher in SBM than in SE (p < 0.05), and the SID of proline was higher in SE than in SBM (p < 0.05). These findings indicate that SE is an appropriate alternative protein source for early weaned pigs. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Digestive tract

International Nuclear Information System (INIS)

Rocha, A.F.G. da

1976-01-01

Scintiscanning of salivary glands with (sup 99m)Tc is commented. The uses of triolein - and oleic acid labelled with 131 I, 125 I or 82 Br are discussed in the study of fat absorption, as well as 14 C and 191 Y. The use of 57 Co as a radiotracer in the intestinal absorption of vitamin B 12 is analysed. Orientation is given about 51 Cr - albumin clearance in the study of plasmatic protein loss by digestive tract. The radiotracers 131 I, 125 I and 51 Cr are pointed out in the investigation of immunoglobulins. Consideration is given to the quantification of digestive bleedings by the use of 51 Cr [pt

Lipid transfer protein: A pan-allergen in plant-derived foods that is highly resistant to pepsin digestion

NARCIS (Netherlands)

Asero, R.; Mistrello, G.; Roncarolo, D.; Vries, de S.C.; Gautier, M.F.; Ciurana, C.L.; Verbeek, E.; Mohammadi, T.; Knul-Brettlova, V.; Akkerdaas, J.H.; Bulder, I.; Aalberse, R.C.; Ree, van R.

2001-01-01

Background: Lipid transfer proteins (LTPs) are stable and highly conserved proteins of around 10 kD. They have recently been identified as allergens in fruits of the Rosaceae family. Objective: The aim of this study was to investigate whether the highly conserved structure of LTPs justifies a

Evaluation of the National Research Council (2001) dairy model and derivation of new prediction equations. 1. Digestibility of fiber, fat, protein, and nonfiber carbohydrate.

Science.gov (United States)

White, R R; Roman-Garcia, Y; Firkins, J L; VandeHaar, M J; Armentano, L E; Weiss, W P; McGill, T; Garnett, R; Hanigan, M D

2017-05-01

Evaluation of ration balancing systems such as the National Research Council (NRC) Nutrient Requirements series is important for improving predictions of animal nutrient requirements and advancing feeding strategies. This work used a literature data set (n = 550) to evaluate predictions of total-tract digested neutral detergent fiber (NDF), fatty acid (FA), crude protein (CP), and nonfiber carbohydrate (NFC) estimated by the NRC (2001) dairy model. Mean biases suggested that the NRC (2001) lactating cow model overestimated true FA and CP digestibility by 26 and 7%, respectively, and under-predicted NDF digestibility by 16%. All NRC (2001) estimates had notable mean and slope biases and large root mean squared prediction error (RMSPE), and concordance (CCC) ranged from poor to good. Predicting NDF digestibility with independent equations for legumes, corn silage, other forages, and nonforage feeds improved CCC (0.85 vs. 0.76) compared with the re-derived NRC (2001) equation form (NRC equation with parameter estimates re-derived against this data set). Separate FA digestion coefficients were derived for different fat supplements (animal fats, oils, and other fat types) and for the basal diet. This equation returned improved (from 0.76 to 0.94) CCC compared with the re-derived NRC (2001) equation form. Unique CP digestibility equations were derived for forages, animal protein feeds, plant protein feeds, and other feeds, which improved CCC compared with the re-derived NRC (2001) equation form (0.74 to 0.85). New NFC digestibility coefficients were derived for grain-specific starch digestibilities, with residual organic matter assumed to be 98% digestible. A Monte Carlo cross-validation was performed to evaluate repeatability of model fit. In this procedure, data were randomly subsetted 500 times into derivation (60%) and evaluation (40%) data sets, and equations were derived using the derivation data and then evaluated against the independent evaluation data. Models

Capillary sieving electrophoresis and micellar electrokinetic capillary chromatography produce highly correlated separation of tryptic digests

Science.gov (United States)

Dickerson, Jane A.; Dovichi, Norman J.

2011-01-01

We perform two-dimensional capillary electrophoresis on fluorescently labeled proteins and peptides. Capillary sieving electrophoresis was performed in the first dimension and micellar electrokinetic capillary chromatography was performed in the second. A cellular homogenate was labeled with the fluorogenic reagent FQ and separated using the system. This homogenate generated a pair of ridges; the first had essentially constant migration time in the CSE dimension, while the second had essentially constant migration time in the MEKC dimension. In addition a few spots were scattered through the electropherogram. The same homogenate was digested using trypsin, and then labeled and subjected to the two dimensional separation. In this case, the two ridges observed from the original two-dimensional separation disappeared, and were replaced by a set of spots that fell along the diagonal. Those spots were identified using a local-maximum algorithm and each was fit using a two-dimensional Gaussian surface by an unsupervised nonlinear least squares regression algorithm. The migration times of the tryptic digest components were highly correlated (r = 0.862). When the slowest migrating components were eliminated from the analysis, the correlation coefficient improved to r = 0.956. PMID:20564272

MALDI-TOF MS for quality control of high protein content sport supplements.

Science.gov (United States)

De Ceglie, Cristina; Calvano, Cosima D; Zambonin, Carlo G

2015-06-01

High protein content sport nutritional supplements are found as powder products containing, as ingredients, amino acids and proteins with important nutritional values as milk, soy and egg proteins. An EU Food Supplements Directive (2002) requires that supplements should be safe, both in dosages and in purity. It is important, then, to develop rapid and sensitive methods to be employed for the quality control of these substances. In this work, we apply, for the first time, matrix-assisted laser desorption ionization-mass spectrometry as a fast, reproducible and sensitive method for the quality control of sport nutritional supplements based on proteins. To this aim, several commercial egg- and/or milk-based powder products have been processed by in gel or in solution digestion and analyzed in comparison to pure standard products. This strategy allowed to assess the reliability of the indications on proteins (as caseins, whey proteins and ovalbumin) declared in the label of several sport nutritional supplements. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of food processing and simulated gastrointestinal digestion on gliadin immunoreactivity in rolls.

Science.gov (United States)

Brzozowski, Bartosz

2018-07-01

The enzymatic modification of wheat proteins during dough fermentation and its digestion as supported by peptidases of microbiological origin can result in the degradation of important peptides in the pathogenesis of coeliac disease. However, baking bread and the high temperature associated with this could change the physicochemical and immunological properties of proteins. Thermal changes in the spatial structure of proteins and their hydrolysis can lead to a masking or degrading of immunoreactive peptides. The addition of prolyl endopeptidase (PEP), comprising peptidases isolated from Lactobacillus acidophilus 5e2 (LA) or transglutaminase (TG) in the course of fermentation, decreases its immunoreactivity by 83.9%, 51.9% and 18.5%, respectively. An analysis of the fractional composition of gliadins revealed that γ- and ω-gliadins are the proteins most susceptible to enzymatic modification. Hydrolysis of wheat storage proteins with PEP and LA reduces the content of αβ-, γ- and ω-gliadins by 13.7%, 60.2% and 41.9% for PEP and by 22.1%, 43.5% and 36.9% for LA, respectively. Cross-linking of proteins with TG or their hydrolysis by PEP and LA peptidases during the process of forming wheat dough, followed by digesting bread samples with PEP and LA peptidases, decreases the immunoreactivity of bread hydrolysates from 2.4% to 0.02%. The content of peptide detected in polypeptide sequences is 263.4 ± 3.3, 30.9 ± 1.5 and 7.9 ± 0.4 mg kg -1 in samples of hydrolysates of bread digested with PEP, as produced from dough modified by TG, PEP and LA, respectively. Enzymatic pre-modification of proteins during the process of dough fermentation decreases their immunoreactive potential, such that fewer peptides recognised by R5 antibodies are released during the digestion process from the bread matrix. Immunoreactive peptides are degraded more effectively when digestive enzymes are supported by the addition of PEP. © 2017 Society of Chemical Industry. © 2017

Effects of Chain Length and Degree of Unsaturation of Fatty Acids on Structure and in Vitro Digestibility of Starch-Protein-Fatty Acid Complexes.

Science.gov (United States)

Zheng, Mengge; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

2018-02-28

The effects of chain length and degree of unsaturation of fatty acids (FAs) on structure and in vitro digestibility of starch-protein-FA complexes were investigated in model systems. Studies with the rapid visco analyzer (RVA) showed that the formation of ternary complex resulted in higher viscosities than those of binary complex during the cooling and holding stages. The results of differential scanning calorimetry (DSC), Raman, and X-ray diffraction (XRD) showed that the structural differences for ternary complexes were much less than those for binary complexes. Starch-protein-FA complexes presented lower in vitro enzymatic digestibility compared with starch-FAs complexes. We conclude that shorter chain and lower unsaturation FAs favor the formation of ternary complexes but decrease the thermal stability of these complexes. FAs had a smaller effect on the ordered structures of ternary complexes than on those of binary complexes and little effect on enzymatic digestibility of both binary and ternary complexes.

Effects of organic composition on mesophilic anaerobic digestion of food waste.

Science.gov (United States)

Li, Yangyang; Jin, Yiying; Borrion, Aiduan; Li, Hailong; Li, Jinhui

2017-11-01

Anaerobic digestion of food waste (FW) has been widely investigated, however, little is known about the influence of organic composition on the FW digestion process. This study aims to identify the optimum composition ratios of carbohydrate (CA), protein (CP) and lipid (EE) for maintaining high methane yield and process stability. The results show that the CA-CP-EE ratio was significantly correlated with performance and degradability parameters. Controlling the CA-CP-EE ratio higher than 1.89 (CA higher than 8.3%, CP lower than 5.0%, and EE lower than 5.6%) could be an effective way to maintain stable digestion and achieve higher methane production (385-627mL/gVS) and shorter digestion retention (196-409h). The CA-CP-EE ratio could be used as an important indicator for digestion performance. To effectively evaluate organic reduction, the concentration and removal efficiency of organic compositions in both solid phases and total FW should be considered. Copyright © 2017. Published by Elsevier Ltd.

Lipid transfer protein: a pan-allergen in plant-derived foods that is highly resistant to pepsin digestion

NARCIS (Netherlands)

Asero, R.; Mistrello, G.; Roncarolo, D.; de Vries, S. C.; Gautier, M. F.; Ciurana, C. L.; Verbeek, E.; Mohammadi, T.; Knul-Brettlova, V.; Akkerdaas, J. H.; Bulder, I.; Aalberse, R. C.; van Ree, R.

2001-01-01

Lipid transfer proteins (LTPs) are stable and highly conserved proteins of around 10 kD. They have recently been identified as allergens in fruits of the Rosaceae family. The aim of this study was to investigate whether the highly conserved structure of LTPs justifies a designation as a true

Digestibility of pasta made with three wheat types: a preliminary study.

Science.gov (United States)

Simonato, Barbara; Curioni, Andrea; Pasini, Gabriella

2015-05-01

The aim of this study was to assess the digestibility of the protein and starch in pasta made with different cereals, i.e. Triticum durum, Triticum polonicum and Triticum dicoccum, and to measure the glycemic index (GI) of the different types of pasta. The digestibility of the starch in T.polonicum pasta differed significantly from the others. It seemed to be less digested than dicoccum and durum wheat pasta. T.polonicum pasta also had a lower glycemic index, while there were no significant differences in the protein digestibility of the three types of pasta. Copyright © 2014 Elsevier Ltd. All rights reserved.

An Evaluation on the Ratio of Plant to Animal Protein in the Diet of Juvenile Sea Cucumber (Apostichopus japonicus): Growth, Nutrient Digestibility and Nonspecific Immunity

Science.gov (United States)

Bao, Pengyun; Li, Xiaoyu; Xu, Yongping

2018-05-01

This study was conducted to evaluate the effects of plant/animal (P/A) protein ratios (viz.1:4, 1:3, 1:2, 1:1,2:1, 3:1, 4:1) on growth performance, body composition, apparent digestibility of diets, and nonspecific immunity of juvenile sea cucumber (Apostichopus japonicus). Sea cucumbers were divided into 21 plastic tanks, and each tank was stocked with 15 individuals (initial weight: about 23.73 g). Each feed was allocated to three replicates of sea cucumbers. The feeding experiment lasted for 50 days. Results indicated that weight gain rate (WGR) and body wall weight (BWW) significantly increased as dietary ratio of P/A increased from 1:4 to 3:1, and then decreased significantly with further increase of this ratio (P 0.05). The apparent digestibility of dry matter, protein and lipid increased with ratio of P/A increasing from 1:4 to 2:1 (P protein (1:1-3:1) significantly increased the growth performance, apparent digestibility, and nonspecific immunity of sea cucumber. This will contribute to improving the feed formulation for juvenile cucumbers.

Digestibility of solvent-treated Jatropha curcas kernel by broiler chickens in Senegal.

Science.gov (United States)

Nesseim, Thierry Daniel Tamsir; Dieng, Abdoulaye; Mergeai, Guy; Ndiaye, Saliou; Hornick, Jean-Luc

2015-12-01

Jatropha curcas is a drought-resistant shrub belonging to the Euphorbiaceae family. The kernel contains approximately 60 % lipid in dry matter, and the meal obtained after oil extraction could be an exceptional source of protein for family poultry farming, in the absence of curcin and, especially, some diterpene derivatives phorbol esters that are partially lipophilic. The nutrient digestibility of J. curcas kernel meal (JKM), obtained after partial physicochemical deoiling was thus evaluated in broiler chickens. Twenty broiler chickens, 6 weeks old, were maintained in individual metabolic cages and divided into four groups of five animals, according to a 4 × 4 Latin square design where deoiled JKM was incorporated into grinded corn at 0, 4, 8, and 12 % levels (diets 0, 4, 8, and 12 J), allowing measurement of nutrient digestibility by the differential method. The dry matter (DM) and organic matter (OM) digestibility of diets was affected to a low extent by JKM (85 and 86 % in 0 J and 81 % in 12 J, respectively) in such a way that DM and OM digestibility of JKM was estimated to be close to 50 %. The ether extract (EE) digestibility of JKM remained high, at about 90 %, while crude protein (CP) and crude fiber (CF) digestibility were largely impacted by JKM, with values closed to 40 % at the highest levels of incorporation. J. curcas kernel presents various nutrient digestibilities but has adverse effects on CP and CF digestibility of the diet. The effects of an additional heat or biological treatment on JKM remain to be assessed.

Reducing crude protein and rumen degradable protein with a constant concentration of rumen undegradable protein in the diet of dairy cows: Production performance, nutrient digestibility, nitrogen efficiency, and blood metabolites.