Different Proportions Of Protein Research Articles

170 Do you Have the Energy to Grind Feed Costs and Maximize Net Income in Demanding Economic Times?

Abstract Energy is not only the most expensive component of the diet, but also among the most complex. Energy impacts all aspects of the growth and metabolism of the pig. Therefore, when feed costs escalate, energy is a predictable though challenging target for increased attention. To achieve greatest success, a two-pronged approach is warranted. The first focuses on our understanding of the fundamentals of energy science and the second logically follows with applying this knowledge in practice. This presentation will address both the science and the application. Formulating energy in pig diets is a complicated process. For example, one can achieve equal dietary energy values with different proportions of protein, starch, fat and fiber. Each of these nutrients is used with a different level of efficiency by the pig, leading one to question whether equal performance should be expected just because ME or NE is the same. We will dig a bit more deeply into how energy values of ingredients are generated, what assumptions are made in this process and the limitations of these values in predicting pig performance. Beyond ME and NE, we will note that changing energy sources may also alter the microbiota, oxidative load, gut structure and function, and even the digestibility of dietary nutrients. This, in turn, can impact not only the performance of the pig, but also resistance to disease and susceptibility to environmental stress. We will also discuss why feed efficiency is sometimes highly correlated to dietary energy but in other cases, this relationship is quite weak; how can this be? On a positive note, the ME or NE of ingredients has been found to be highly correlated with certain dietary constituents. This infers that the prediction of the energy content of ingredients should be quite effective, and such predictions will improve the precision of diet formulation. Moving forward, it makes sense that wherever possible, energy response curves should be part of the toolkit available to swine nutritionists, but these curves should involve diverse diet composition, unlike the energy titration studies commonly used in our industry. When energy is the most expensive, and production margins are weakest, this is the very time to invest strategically in diet analysis to ensure that we are extracting every bit of energy we can from available ingredients. In other words, are we achieving our formulation targets? Because the topic of dietary energy is so large and complex, we will remind ourselves where we can have the greatest impact on net income by managing energy. In conclusion, energy drives feed costs and drives performance. As complex a topic as it is, we will be rewarded by understanding dietary energy more deeply, and applying that knowledge as effectively as possible in commercial practice.

The Consistency Factor and the Viscosity Exponent of Soybean-Protein-Isolate/Wheat-Gluten/Corn-Starch Blends by Using a Capillary Rheometry.

Blends with different proportions of protein or starch show different rheological behaviors, which may be related to the fibrous structure formation of extruded textured plant proteins. The consistency factor K and the viscosity exponent n of soybean–protein–isolate (SPI)/wheat–gluten (WG)/corn–starch (CS) blends were investigated through capillary rheometry. All blends exhibited shear-thinning behavior at 80 °C and 50% moisture. The CS content in SPI/CS blends or WG content in SPI/WG blends showed a positive relation to the viscosity exponent n and a negative relation to the consistency factor K. However, there was no correlation between the CS content in WG/CS blends and n or K. The coefficient of determination of the linear relationship between K and mass fraction in SPI/CS, SPI/WG/CS, SPI/WG and WG/CS decreased from 0.872 to 0.073. SPI was more likely to form a non-interactive structure, while wheat-gluten was more likely to form a highly interactive structure. It turned out that the materials with globular morphology, such as soybean-protein-isolate and corn-starch, are likely to form a non-interactive structure.

Effect of starch and fibre on faba bean protein gel characteristics

Faba bean is a promising alternative to soybean for production of protein-rich plant-based foods. Increased understanding of the gelling behaviour of non-soy legumes can facilitate development of novel plant-based foods based on other legumes, such as faba bean. A mixture design was used in this study to evaluate the effect of different proportions of protein, starch and fibre fractions extracted from faba beans on gelation properties, texture and microstructure of the resulting gels. Large deformation properties, in terms of fracture stress and fracture strain, decreased as fibre and/or starch replaced protein. In contrast, Young's modulus and storage modulus increased with substitution of the protein. Light microscopy revealed that for all gels, protein remained the continuous phase within the region studied (65–100% protein fraction, 0–35% starch fraction, 0–10% fibre fraction in total flour added). Swollen and deformed starch granules were distributed throughout the mixed gels with added starch. Leaked amylose aggregated on starch and fibre surfaces and in small cavities (<1 μm) throughout the protein network. No clear difference between samples in protein network structure was observed by scanning electron microscopy. The reduction in large deformation properties was tentatively attributed to inhomogeneities created by the added starch and fibre. The increase in small deformation properties was hypothesised to be affected by water adsorption and moisture stability through the starch and fibre, increasing the effective protein concentration in the surrounding matrix and enhancing the protein network, or potentially by starch granules and fibre particles acting as active fillers reinforcing the gel structure. • Partly replacing protein with starch and/or fibre reduce the fracture stress. • Partly replacing protein with starch and/or fibre increase the storage modulus. • Addition of starch and/or fibre did not largely alter the protein network structure.

Proliferation of Bifidobacterium L80 under different proportions of milk protein hydrolysate

The intestinal microecological environment is critical to an infant's growth. For those infants consuming milk power, it is very important to improve the intestinal microecological environment to promote the healthy growth of infants. In this paper, Milk protein hydrolysate (MPH), consisting of different proportions of proteins and small molecule peptides (5:5, 4:6, 3:7, 2:8, 1:9) were added to infant formula powder (IFP). The effects of MFP-enriched IFP addition on proliferation and metabolism of Bifidobacterium L80 were studied. Compared with MPH-free IFP, MFP-enriched IFP with 1:9 of proteins to small molecule peptides significantly enhanced the proliferation of Bifidobacterium L80, resulting in higher cell density, greater viable counts and higher titratable acidity. MFP-enriched IFP increased the content of seven organic acids and H2O2 in the system, and improved the antibacterial activity to E. coli BL21. This study suggested that MPH could be an effective addition to infant formula powder to promote the growth of Bifidobacterium, so to improve the intestinal health of infants.

Structural changes in cow, goat, and sheep skim milk during dynamic in vitro gastric digestion

Coagulation of milk in the stomach is the first crucial step in its digestion. Using a human gastric simulator, the dynamic gastric digestion of goat and sheep skim milk were compared with that of cow skim milk, focusing particularly on their physical characteristics. The gastric contents were analyzed for changes in dry matter and microstructure, and the extent of protein digestion. The study revealed that the skim milk from all species formed a curd within the first 15 min of gastric digestion, at which time the pH was ~6.1 to 6.3. Compared with cow skim milk, the dry matter contents of the clots formed from goat and sheep skim milk were lower and higher, respectively, which was due to the differences in their total solids and protein contents. Microstructural analysis showed that, as digestion progressed, the clot structure became more cohesive, along with a decrease in moisture content, which in turn affected the breakdown and hydrolysis of caseins by pepsin; this phenomenon was similar for milk from all species. However, the extent of moisture retained in the sheep skim milk clot appeared to be lower than those of the cow and goat skim milk clots. In addition, the relative firmness of the sheep milk clot was higher than those of the cow and goat milk clots at the end of gastric digestion. The pattern of protein hydrolysis by pepsin was similar for the milk of all species, despite the differences in the proportions of different proteins. The study provided insight into the coagulation kinetics of goat and sheep skim milk under in vitro gastric digestion conditions.

Effects of Diets with Different Proportions of Protein/Carbohydrate on Retinal Manifestations in db Mice.

Diabetic nephropathy is aggravated by a higher intake of total protein. The effects of diets with different proportions of protein and carbohydrate on diabetic retinopathy in db mice, a type-2 diabetes animal model, were examined, as well as diabetic nephropathy. Control and db mice at 5 weeks of age were fed the diets (% energy of protein/carbohydrate/fat; L-diet: 12/71/17; H-diet: 24/59/17) under ad libitum conditions and pair-feeding conditions for 6 weeks, respectively. Mice fed the H-diet showed significantly greater retinal thickness by optical coherence tomography, and lower mRNA levels of angiotensinogen. Comparing combinations of diets and genotypes, db-H mice showed significantly higher mRNA levels of angiotensin-converting enzyme, advanced glycosylation end product-specific receptor, and cluster of differentiation molecule 11b (a microglial marker) than db-L mice. Dietary protein and carbohydrate proportions influenced retinal manifestations, including retinal thickness and gene expression in control and diabetic mice.

Understanding key constituents and feature of the biopolymer in activated sludge responsible for binding heavy metals

The biopolymer in activated sludge plays an important role in the removal of heavy metals, and it can also be extracted to serve as biosorbent for heavy metals. It is of big interest to understand the key constituents and feature of the biopolymer. In this study, the biopolymers with quite different proportions of constituents were extracted from activated sludge after the conditioning by cetyl trimethyl ammonium bromide (CTAB) and linear alkylbenzene sulfonate (LAS), and then were used to test their adsorbability for metal ions. CTAB was prominent in increasing proteins (PN) content, and LAS was prominent in increasing polysaccharides (PS) and nucleic acids (NA) content. The biopolymers with different proportions of PN, PS and NA showed different adsorption capacities for Cu2+ (ranging from 258.94 to 389.92mg/g). Their adsorption capacities significantly correlated with proteins (R2=0.9225, P=0.00), proteins/polysaccharides (R2=0.9797, P=0.00), polysaccharides (R2=0.6739, P=0.01), and nucleic acids (R2=0.6960, P=0.00). The adsorption capacities showed significant positive correlation with proteins and proteins/polysaccharides, but negative correlation with polysaccharides and nucleic acids. Proteins and high proteins/polysaccharides were identified to be the key constituents and feature of the biopolymer responsible for binding heavy metals, respectively. The findings denote that all biomass with high protein content could be an excellent adsorbent for metal ions.

Interaction between ingested nutrients and gut endocrine cells in patients with irritable bowel syndrome (review).

Several endocrine cell abnormalities have been reported in different segments of the gastrointestinal tract of patients with irritable bowel syndrome (IBS). These cells have specialized microvilli that project into the lumen; they function as sensors for the gut contents and respond to luminal stimuli (mostly ingested nutrients) by releasing hormones into the lamina propria, where they exert their effects via a paracrine/endocrine mode of action. Certain food items trigger the symptoms experienced by IBS patients, including those rich in fermentable oligo-, di- and monosaccharides, and polyols (FODMAPs). In this review, we present the argument that the effects of both FODMAPs and the proportional intake of proteins, fats and carbohydrates on IBS symptoms may be caused by an interaction with the gut endocrine cells. Since the gut hormones control and regulate gastrointestinal motility and sensation, this interaction may be responsible for abnormal gastrointestinal motility and the visceral hypersensitivity observed in these patients. There is no consistent evidence that IBS patients suffer from food allergy. The role of gluten intolerance in the development of IBS symptoms in these patients remains a matter of controversy. Individual guidance on food management, which includes restrictions in the intake of FODMAP-rich foods and testing diets with different proportions of proteins, fats and carbohydrates has been found to reduce the symptoms, improve the quality of life, and make the habitual diet of IBS patients more healthy.

Effect of extracellular polymeric substances on corrosion of cast iron in the reclaimed wastewater

Microorganisms were cultured in the R2A medium with inoculum from biofilm in a reclaimed wastewater distribution system and then extracellular polymeric substances (EPS) were extracted from the culture. Characterization of EPS and their effects on the corrosion of cast iron were examined. EPS extracted from different culturing stages contained different proportions of protein and polysaccharide but with similar functional groups. All types of EPS could inhibit cast iron corrosion and the EPS from the stationary stage had the highest inhibition efficiency. The inhibition efficiency was increased with addition of a small amount of EPS while decreased with excessive amount of EPS. EPS formed a protective film on the metal surface, which retarded the cathodic reduction of oxygen. Excessive amount of EPS promoted anodic dissolution through EPS–Fe binding. The CO and C(O, N) in EPS could be the anodic electrochemical sites with possible products of C(C, H).

Antisolvent vapour precipitation of droplets with multi-components: Non-soluble encapsulation and simultaneous precipitation of soluble materials

A new antisolvent vapour precipitation technique was developed which enables the production of a large amount of micro spheres from a single droplet. This work explores the potential of this technique for encapsulation of oil and in precipitating multi-component solutes from a droplet. Experiments were undertaken on the single droplet drying rig in Monash University, modified to incorporate antisolvent vapour. Using ethanol vapour, lactose micro particles with spiky surfaces were formed. Oil-infused lactose micro particles were also observed delineated by the smooth surfaces analogous to that of full cream milk. Precipitation of multi-component solutes resulted in partial segregation of the protein and lactose. Precipitated particles with different proportions of protein and lactose exhibited contrasting particles. Particles with higher protein content resulted in smaller particle sizes.

Effects of variable protein and lipid proportion in gilthead sea bream (Sparus aurata) diets on fillet structure and quality

Juvenile gilthead sea bream (Sparus aurata) were fed with seven experimental diets containing different proportions of protein and lipid (P/L): 38/29, 41/26, 44/25, 47/23, 50/22, 54/21 and 57/20 per cent of dry matter, respectively. After 12 weeks, fish fed on diet 38/29 (P/L) showed the lowest food efficiency and final weight. A correlation between the hepatosomatic index and fat content in the diets was observed, together with a decrease in muscle glycogen in animals fed with a 38/29 (P/L) diet. Whilst no statistical differences were found in flesh texture, a clear relationship was observed between elasticity and fibre density. Fillet Chroma was altered in the animals fed with the 38/29 (P/L) diet. The same group showed a decrease in hepatic growth factor receptor (c-met) and proliferating cell nuclear antigen (PCNA) expression in white muscle. Protein content in the diets correlated with mammalian target of rapamycin (mTOR) phosphorylation in muscle. In conclusion, we have shown that the substitution of protein by lipid in sea bream diets can be performed up to a certain percentage without affecting fish growth, and we have demonstrated that several molecules such as MyoD, mTOR, PCNA and c-met are affected by the dietary ratio of protein to lipid and could be potential flesh quality markers.

Influence of diets on the rearing of predatory flies of housefly larvae

The purpose of this study was to evaluate the survival, development time and morphological measures of immature Ophyra aenescens and Ophyra albuquerquei on different diets. Different proportions of protein and carbohydrates were offered for each species in 10 vials containing 30 eggs each. The vials were placed in a germination chamber at 30°C, relative humidity above 75% and photoperiod of 12 hours. Every day a vial was removed and mortality was evaluated and on the tenth day the length of the cephalic-pharyngeal skeleton (EC) and body size (G) of larvae that survived were evaluated. Survival was higher in diets with more protein (P&lt;0.001). Between the species, mortality was more pronounced in O. albuquerquei in all diets (P&lt;0.001). The EC (P&lt;0.01) and G (P&lt;0.01) showed the same sizes in the diets with higher protein content. For the production of pupae of these species, the diet with more protein and fewer components is more appropriate, and the production is higher in O. aenescens than in O. albuquerquei.

Biochemical characterization and physiological role of cortical rods in black tiger shrimp, Penaeus monodon

Cortical rods (CRs), precursors of egg jelly investment in many penaeoid shrimp, are composed of different proportions of proteins and carbohydrates, the physiological role of which still requires extensive investigation. In this study, we demonstrated the biochemical properties of the CRs and their role in the induction of the acrosome reaction (AR). Profiles of the isolated CRs revealed a number of major protein bands ranging from 35 to 230 kDa. These CR proteins were extensively glycosylated and sulfated. Lectin-based carbohydrate analysis further revealed the highest reactivity of concanavalin A (Con A) among other lectins used. In addition, the selective interference of Con A binding with mannose but not glucose indicated that CR glycoproteins were of high-mannose type. Using immunoblotting with anti-CR antibody, we further demonstrated that part of egg water (EW, a natural AR inducer) was derived from miscible components of the CRs. Physiological tests of water-soluble CR (wsCR) revealed its high AR inducing competency comparable to that of EW, which was far superior to that of acid-urea treated CR (auCR). Furthermore, the wsCR-induced AR was selectively inhibited by Con A, suggesting the significance of the exposing mannose residues in regulating P. monodon sperm AR response.

Elucidation of the Emulsification Properties of Sugar Beet Pectin

A protocol has been developed to fractionate sugar beet pectin using hydrophobic affinity chromatography. Three samples eluted from the column using 4 M NaCl as solvent (fractions 1A, 1B, and 1C), two fractions eluted using 2 M NaCl (fractions 2A and 2B), and one fraction eluted using water (fraction 3). The fractions were shown to be very polydisperse, and differences between the GPC refractive index and UV absorbance (214 nm) elution profiles demonstrated chemical heterogeneity. They were found to contain significantly different proportions of protein (1A, 2.79%; 1B, 0.97%; 1C, 0.77%; 2A, 1.41%; 2B, 5.09%; and 3, 5.89%) and ferulic acid (approximately 1A, 0.5%; 1B, 0.5%; 1C, 0.9%; 2B, 1.5%; and 3, 2%). The weight-average molecular mass, M(w), of the fractions also varied (1A, 153 kDa; 1B, 155 kDa; 1C, 306 kDa; 2A, 562 kDa; 2B, 470 kDa; 3, 282 kDa). Three fractions, that is, 1A, 1B, and 3, produced orange oil emulsions with a relatively small droplet size that were stable over a period of weeks. The other three fractions (1C, 2A, and 2B with higher M(w) values) produced emulsions with an initially larger droplet size, and the droplet size increased considerably over time. The increased droplet size may be influenced by the viscosity of the aqueous continuous phase. There was no simple relationship between protein or ferulic acid content and emulsification ability. For example, fraction 1B, which contained the lowest proportion of both protein and ferulic acid, produced stable emulsions of similar droplet size to fraction 3, which contained the largest proportion of protein and ferulic acid. The role of protein in the emulsification process was investigated by measuring the amount of protein in the aqueous phase before and after emulsification. It was clearly demonstrated that proteinaceous material adsorbed at the oil-water interface. It is evident that the emulsification properties of sugar beet pectin are influenced by the accessibility of the protein and ferulic acid groups to the surface of the oil droplets, the proportion of ester groups, and the molecular mass distribution of the fractions.

A new method of estimating the proportions of different proteins in a mixture using amino acid profiles: application to undigested proteins in the preruminant calf

A new method of estimating the proportions of different proteins in a mixture using amino acid profiles: application to undigested proteins in the preruminant calf

The effect of different proportions of protein and antibiotic in the diet on reproductive performance of indigenous pigs in Nigeria

SummaryOne hundred and twelve indigenous gilts and sows were used in two trials to study the effects of strepcillin (a mixture of streptomycin and penicillin) at 0, 25, 50, 75 and 100 g/t feed in a basal 15% protein diet and strepcillin at 0, 25, and 50g/t feed in rations containing 12, 15 and 18% protein, on the reproductive performance of pigs.Reproductive performance in terms of sow net gain in weight through the reproductive cycle, average birth weight of live pigs per litter and number of pigs weaned per litter were significantly affected by antibiotic levels. The dietary level of 50 g antibiotic/t feed gave the highest reproductive performance though at higher levels no adverse effects on reproductive performance were obtained.Reproductive performance of pigs was significantly influenced by protein and antibiotic levels. A significant interaction between antibiotic and protein levels was obtained for weight loss in sows at parturition and lactation, net gain in weight through the reproductive cycle, total and live pigs farrowed per litter.

Interaction between nutrition and theophylline metabolism in children.

The influences on theophylline metabolism are multifactorial, resulting in significant inter- and intrapatient variability in drug responsiveness. Clinical investigations with adult patients have demonstrated the influence of diet on theophylline metabolism following a single drug dose. We have undertaken this study to examine the effect of nutritional factors on theophylline pharmacokinetics in 14 asthmatic children receiving the drug on a chronic basis. For 12-day periods each patient received three separate diets with different proportions of protein and carbohydrate but with constant fat and caloric intake. Significant differences were detected for theophylline half-life, apparent volume of distribution, and metabolic clearance rate. The high-protein diet markedly shortened the drug-elimination half-life relative to a normal diet, and high carbohydrate significantly increased it (both p less than 0.001). Other kinetic parameters confirmed this pattern. Our findings in children clearly establish that nutritional factors have a significant environmental influence on theophylline metabolism during the drug's steady-state pharmacokinetics.

Synthesis of nitrogenase by isolated heterocysts

Heterocysts isolated from Anabaena variabilis incorporate [ 14C]leucine and [ 35S]methionine into trichloroacetic acid-precipitable material in the light. Analysis by polyacrylamide gel electrophoresis shows that the radioactivity is present in polypeptides of discrete sizes. However, the relative proportions of different proteins synthesized by isolated heterocysts differ from the relative proportions of those proteins incorporated by the heterocysts in intact filaments. The two components of nitrogenase are among the proteins synthesized by the isolated heterocysts.

Ingestion rates, food utilization and turnover of water and sodium in grazing buffaloes, Bubalus bubalis, and cattle, Bos taurus × B. indicus, in monsoonal Northern Territory

Cows and steers of swamp buffalo and Brahman x Shorthorn cattle grazing freely in a paddock of pangola grass pasture during a monsoonal dry season were compared over 14 days in body composition, rates of sodium and water turnover, and rates of food ingestion by using the isotope dilution method. The cattle, especially the steers, had a higher proportion of body solids than the buffalo and appeared to have a higher proportion of body fat. There were significant interactions of species with either sex, castration or both in the proportions of body water and solids. The differing body compositions had a marked influence in comparisons of physiological rate parameters between the buffalo and cattle. The buffalo had higher rates of water turnover than the cattle and the two species had similar rates of sodium turnover when standardized for body size and composition. The rates of food consumption of the buffalo and cattle were significantly different when expressed per animal and expressed relative to metabolic body mass, with greater rates in the buffalo. When the influence of differing body compositions was removed, the rates of food consumption were not significantly different between species but approached significance. The species showed similar rates of mass gain but the cows of both buffalo and cattle had greater rates than the steers. The conversion efficiency of food to body mass was not statistically different between buffalo and cattle, but the composition of the respective increments may have differed, possibly by different proportions of protein and lipid. This is discussed with respect to the relative efficiencies of nitrogen conservation in buffalo and cattle. It is concluded that buffalo and cattle have different water physiology and broadly similar nutritional efficiencies. The performances of the two species in the monsoonal tropics differ for ecological reasons ensuing from different behavioural adaptations and water physiology.

Specific Dynamic Action and Diet in Largemouth Bass, Micropterus salmoides (Lacépède)

Apparent specific dynamic action (SDA) in largemouth bass (5-28 g) was equated to oxygen uptake subsequent to the ingestion of a meal. The effects of six diets on apparent SDA were investigated, one balanced or standard diet and five consisting of different proportions of protein and carbohydrate. Apparent SDA was positively related to gross energy ingested and to the level of dietary protein. For a given energy intake, apparent SDA was highest and lowest for diets of 100% protein and 100% carbohydrate, respectively. Evidence of a protein-sparing effect was found when the carbohydrate component represented 25% of the diet and the energy intake was less than 0.8 kcal. Apparent SDA was divided into mechanical SDA, the energy cost for the physical processing of food, and biochemical SDA, the energy cost of anabolic and catabolic processes associated with a meal. Biochemical SDA increased with energy ingested irrespective of diet and was higher by approximately an order of magnitude when bass were fed 1.5 kcal of a 100% protein diet than when fish received an isocaloric meal of 100% carbohydrate. Rate of oxygen uptake following feeding remained above the prefeeding level for 12-72 hours depending on diet and energy ingested.