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Background The association between dietary protein intake and the risk of mortality is still controversial. The present study aimed to examine the associations between dietary total, animal and plant protein intake and all-cause and cause-specific mortality. Methods Community-dwelling men aged ≥ 70 years were recruited from local government areas surrounding Concord Hospital in Sydney, New South Wales for the Concord Health and Ageing in Men Project (CHAMP). The research dietitian administered a standardised validated diet history questionnaire to capture baseline dietary intake. In total, 794 men participated in a detailed diet history interview at the third wave. Adequacy of protein intake was assessed by comparing participant intake with the Nutrient Reference Values. Total protein intake was categorised into quintiles. Sources of protein were also captured. Mortality was ascertained through the New South Wales death registry. Cox proportional hazard models were used to assess the association between dietary total, animal and plant protein intake and risk of mortality. Results The mean age of the CHAMP men was 81 years. In total, 162 men died during a median follow-up of 3.7 years. Of these, 54 (33.3%) and 49 (30.2%) men died due to cancer and cardiovascular disease, respectively. There were U-shaped associations between protein intake and all-cause and cancer mortality. In multiple adjusted analysis, the second (hazard ratio [HR] = 0.38; 95% confidence interval [CI] = 0.18-0.82) and third (HR = 0.36; 95% CI = 0.16-0.82) quintiles of protein intakes were significantly associated with reduced risk of all-cause and only second quintile (HR = 0.47; 95% CI = 0.10-0.93) of protein intake was significantly associated with cancer mortality. Each serve increase in animal protein was significantly associated with 12% (HR = 1.12; 95% CI = 1.00-1.26) and 23% (HR = 1.23; 95% CI = 1.02-1.49) increased risk of all-cause mortality and cancer mortality respectively. Conversely, each serve increase in plant protein intake was significantly associated with 25% (HR = 0.75; 95% CI 0.61-0.92) and 28% (HR = 0.72; 95% CI = 0.53-0.97) reduced risk of all-cause and cancer mortality, respectively. No such associations were observed for cardiovascular disease mortality. Conclusions Both second and third quintiles of total protein intake were associated with reduced all-cause and cancer mortality. Plant protein was inversely associated with all-cause and cancer mortality, whereas animal protein intake was positively associated with mortality.

The study examined the potential nutritive value of rice protein (RP) through Maillard reaction. Structures and properties of synthetic conjugates of RP and exopolysaccharide (EPS) from Arthrobacter ps‐5 were investigated systematically. Fluorescence characteristics and high molecular weight compounds appeared in Maillard reaction products (MRPs). Moreover, EPS or its degradation products in the form of covalent bond cross‐linked with RP were identified, where –NH2 disappeared and C=O, C=N and C–N increased. Determination of free –SH residues suggested mutual conversion between disulfide bonds and sulfhydryl groups occurred during Maillard reaction. HPLC analysis identified conjugates with different molecular weight, where melanoprotein was formed by covalent bonds. As RP conjugated with EPS, the molecules spread out and changed the spatial structure. Functional properties of MRPs, including solubility, foaming activity, emulsifying ability and resistance to oxidation, were greatly improved. The study has discovered an efficient method for increasing the application value of plant protein.

Hemp seed protein has the potential to be used in food systems as an emulsifying agent; however, there are still some shortcomings associated with hemp seed protein, such as poor solubility and tendency to aggregate. This study aims to improve the dispersibility of hemp seed protein as an emulsifier by complexing with pectin, driven by electrostatic force. Three protein to pectin ratios were used for complexation, from 1:1, 2:1 to 4:1. The complexation improved the polydispersity of hemp seed protein when dispersed in the aqueous phase. The hemp seed protein displayed multimodal size distribution in water at pH = 3.0 due to aggregation, while the incorporation of pectin helped to diminish those aggregated proteins. When the hemp seed protein was used to stabilize the oil-in-water emulsion, its stabilized emulsion showed promising homogenous droplet size distribution after emulsification. However, during the accelerated storage conditions (55°C), the emulsion stabilized solely by hemp seed protein was subjected to extensive coalescence. From day 0 to 9, the droplet size (d4,3 ) increased by 50 folds from 3.215 to 161.6 µm. In contrast, the hemp seed protein-pectin complex exhibited extraordinary stability during the storage test, where size evolution in all three samples was negligible compared to the emulsion stabilized by hemp seed protein. Rheological characterization suggests that pectin provided physical strength, which may help the emulsion droplets to maintain structural integrity under environmental stress. The underlying mechanism could be associated with the formation of a three-dimensional structure by pectin through bridging adjacent emulsion droplets. PRACTICAL APPLICATION: Hemp seed protein is gaining more and more attention as an emerging plant protein. Recently, hemp seed protein has been explored as an emulsifier, but its stabilized emulsion encounters instability issues during storage. Our study suggests pectin could be used as a co-stabilizer for hemp seed protein emulsions.

Background The increasing importance of plant-based proteins in the food sector makes a reliable compositional analysis of plant-based high-protein ingredients a necessity. Specifically, the quantification of short-chain carbohydrates is relevant for multiple areas, including food product development, food labelling and fundamental food chemistry and food technology research. Commonly used extraction procedures for subsequent high-performance liquid chromatographic separation and quantification of short-chain carbohydrates have been discussed controversially regarding a range of complications that can potentially lead to inaccurate sugar determination. The present study compares the sugar levels in wheat flour and wholemeal wheat flour determined with different aqueous and ethanolic extraction procedures. These procedures included measures to prevent enzyme activity and microbial growth, which represent two of the most relevant challenges in sugar extraction from food samples. Results Differences in sugar levels (sum of sucrose/maltose, glucose and fructose) as high as 1.8% dry matter (wheat flour) were observed between the employed extraction procedures. Ethanolic extraction (80% ethanol in ultrapure water) with the use of the antimicrobial agent sodium azide but without Carrez clarification was identified as most promising for sugar determination in plant-based high-protein ingredients. Conclusion A screening of high-protein ingredients derived from cereals (wheat gluten), pseudocereals (quinoa, amaranth, buckwheat) and legumes (soy, pea, lupin, lentil, carob, chickpea, faba bean) concerning their levels of sucrose, maltose, glucose and fructose confirmed the applicability of the chosen extraction procedure. © 2021 Society of Chemical Industry.

As global population growth and meat consumption increases, sustainable alternatives to conventional protein-rich fodder crops for livestock are needed to reduce negative environmental impacts. Duckweed, a small floating aquatic plant, can generate 5 to 10 times higher protein yields than conventional land-grown crops. Although some in vivo feeding trials with duckweed have been conducted, those measuring animal weight are limited, and those examining organ development are nonexistent. To secure broad acceptance of new protein sources, such controlled studies are critical. This study measured the food intake, growth, and final organ and adipose tissue mass of male CF-1 mice fed a semi-purified diet containing casein or diets in which 10% or 25% of the casein was replaced with duckweed protein (DWP). Proximate analysis showed that the DWP preparation used contained 39.9% protein (w/w), and contained all of the essential amino acids with Met as the limiting amino acid. The average growth rates were not significantly different among the treatment groups: 0.21 g/day; 0.24 g/day; and 0.25 g/day for the control, 10%, and 25% DWP protein diets, respectively. The daily food intake of both DWP diets was 6.5% to 8.0% higher than the control diet, but feeding efficiency did not differ among diets. The relative weight of the liver, spleen, kidneys, heart, and epidydimal fat, and colon length were not significantly different between treatment groups. The results from this study show that replacement of up to 25% dietary casein with DWP has no adverse effects on the growth rate and final organ and adipose tissue weights of laboratory mice. PRACTICAL APPLICATION: Duckweed can produce 5 to 10 times more protein per area than land-grown crops such as soybean. In this study, up to a 25% replacement of casein with duckweed protein had no observable effect on the growth or organ development of laboratory mice. Thus, duckweed has the potential to be used as a protein supplement for livestock, poultry, and fish, thereby decreasing environmental impacts from land-grown crops used for animal feed.

Background The fortification of cereal foods, like pasta, with pseudocereal and legume ingredients promises a substantial improvement of their nutritional quality. However, partial replacement of wheat by pseudocereals and legumes in pasta formulations bears challenges regarding the products' technological and sensory quality. This study investigates the partial replacement of wheat semolina by a combination of high-protein ingredients (HPIs) from buckwheat, faba bean and lupin to reach a protein level of 20% of calories provided by protein. This high-protein hybrid pasta (HPHP) formulation was subjected to a thorough evaluation of technological quality characteristics and compared to regular wheat pasta and pasta formulations containing the single HPIs. Additionally, descriptive sensory profiling was performed to compare organoleptic properties of HPHP with regular wheat pasta. Results The quality of pasta formulations containing single HPIs was significantly reduced with regard to at least one of the determined quality characteristics. For the HPHP formulation containing all three HPIs, the technological quality was found to be equal to regular wheat pasta. No significant differences were detected for the most indicative quality characteristics cooking loss, firmness and stickiness. This was attributed primarily to compensating effects of the HPIs with respect to different quality characteristics. Sensory analysis revealed only slightly inferior overall quality of HPHP in comparison to regular wheat pasta, especially promoted by similar textural properties. Conclusion The combination of selected HPIs offers the opportunity to produce high-protein hybrid pasta with technological and sensory quality similar to regular wheat pasta at a level of wheat semolina replacement of 25%. © 2020 Society of Chemical Industry.

A growing demand for alternative sources of texturized vegetable protein (TVP) has resulted from various factors including plant allergies, perceived health risks associated with genetically modified organisms (GMO), animal welfare beliefs, and lifestyle choices. Soy and wheat have been the primary ingredients in TVP over the past few decades, but desires for clean label ingredients (especially non-GMO and nonallergenic) have led to demand for alternative plant protein ingredients such as pea protein. To understand the capabilities of pea protein to create meat-like texture with additions of another protein source that also contributes starch, this study focused on extruding pea protein with increasing amounts of chickpea flour (CPF). Six treatments, with inclusions of CPF ranging from 0 to 50%, were processed on a twin-screw extruder to determine the optimal ratio of pea protein isolate to CPF. Bulk density was the greatest with 20% CPF (272 g/L) and resulted in the lowest water holding capacity (55.5%). Texture profile analysis (TPA) hardness, springiness, and chewiness showed optimum results for the 10 and 20% CPF (674 to 1024 g, 72.1 to 80.7%, 400 to 439, respectively). With no CPF addition, protein interactions created a strong network exhibiting extreme springiness (91.3%). Addition of CPF greater than 20% resulted in a detrimental decrease in hardness by 38 to 84% and chewiness by 73 to 92%. Phase transition analysis and specific mechanical energy data provided a greater understanding of the degree of texturization during extrusion. Inclusion of CPF between 10 and 20% led to the optimum protein to starch ratio, allowing adequate protein texturization and creating product characteristics that could potentially mimic meat. PRACTICAL APPLICATION: Pea protein was mixed with increasing levels of chickpea flour to produce a textured plant protein product using extrusion technology. The ratio of protein to starch can be optimized to target specific textural attributes of textured pea protein to closely mimic different meat products like fish, chicken, or beef. The 10 and 20% chickpea flour treatments produced the highest quality products according to textural attributes.

In plants, autophagy is involved in responses to viral infection. However, the role of host factors in mediating autophagy to suppress viruses is poorly understood. A previously uncharacterized plant protein, NbP3IP, was shown to interact with p3, an RNA-silencing suppressor protein encoded by Rice stripe virus (RSV), a negative-strand RNA virus. The potential roles of NbP3IP in RSV infection were examined. NbP3IP degraded p3 through the autophagy pathway, thereby affecting the silencing suppression activity of p3. Transgenic overexpression of NbP3IP conferred resistance to RSV infection in Nicotiana benthamiana. RSV infection was promoted in ATG5- or ATG7-silenced plants and was inhibited in GAPC-silenced plants where autophagy was activated, confirming the role of autophagy in suppressing RSV infection. NbP3IP interacted with NbATG8f, indicating a potential selective autophagosomal cargo receptor role for P3IP. Additionally, the rice NbP3IP homolog (OsP3IP) also mediated p3 degradation and interacted with OsATG8b and p3. Through identification of the involvement of P3IP in the autophagy-mediated degradation of RSV p3, we reveal a new mechanism to antagonize the infection of RSV, and thereby provide the first evidence that autophagy can play an antiviral role against negative-strand RNA viruses.

Proteins play many technological, physicochemical and sensory roles (i.e. functionalities) in foods, including solubility, emulsifying, gelling, foaming and flavour creation. In comparison with animal proteins, plant proteins have different structure, composition and food functionality. This review discusses how protein can be extracted from plant materials to produce protein‐rich ingredients for creating plant‐based foods. It explores the potential for a new generation of semi‐purified plant‐derived ingredients with greater sustainability and health benefits.

Open Access via Wiley publishing agreement. Rural and Environment Science and Analytical Services Division (GrantNumber(s): 1st April 2016 \ 31st March 2022) Minister of Science and Higher Education (GrantNumber(s): Project No. 010/RID/2018/19)

BACKGROUND Given the importance of habitual dietary protein intake, distribution patterns and dietary sources in the aetiology of age-related declines of muscle mass and function, the present study examined these factors as a function of sex and age in Irish adults aged 18-90 years comprising The National Adult Nutrition Survey (NANS). METHODS In total, 1051 (males, n = 523; females, n = 528) undertook a 4-day semi-weighed food diary. Total, body mass relative intake and percentage contribution to total energy intake of dietary protein were determined in addition to protein distribution scores (PDS), as well as the contribution of food groups, animal- and plant-based foods to total protein intake. RESULTS Total and relative protein intake [mean (SD)] were highest in those aged 18-35 years [96 (3) g day-1 , 1.32 (0.40) g kg-1 day-1 ], with lower protein intakes with increasing age (i.e. in adults aged ≥65 years [82 (22) g, 1.15 (0.34) g kg-1 day-1 , P

Background Bioprocessing of plant feedstuff can be a novel approach for reducing the overwhelming dependence on fish meal in aquaculture. The objective of this study was to evaluate the performance of Pacific white shrimp Litopenaeus vannamei fed solid-state fermented protein concentrates in order to replace fish meal in the diet. Results In the first trial, a group of 15 shrimp (average 3.88 g) were randomly distributed into aquaria in triplicate according to the experimental diets. Ten isonitrogenous (400 g kg-1 CP) and isolipidic (90 g kg-1 CL) diets were formulated to contain high-protein fish meal (HFM) and low-protein fish meal (LFM), and four types of bioprocessed protein concentrates (BPCs) as a replacement of fish meal (BPC-A, -B, -C and -D) each at 30% and 50% FM replacement levels. BPC-A was a solid-state fermented mixture of soybean and corn gluten meals; BPC-B was pre-treated acid-hydrolyzed BPC-A; BPC-C and BPC-D were BPC-A + 2% shrimp soluble extract (SSE) and BPC-B + 2% SSE, respectively. After 8 weeks, shrimp fed the HFM, BPC-B, BPC-C and BPC-D diets showed significantly higher growth performance at 30% FM replacement than those of shrimp fed the BPC diets at 50% FM replacement. Interestingly, shrimp fed the BPC-D diet could replace up to 50% FM replacement. In the second trial, the results show that apparent digestibility coefficients of feeds and apparent digestibility coefficients of ingredients for crude protein were significantly higher in fish fed the BPC-B, BPC-C and BPC-D diets. Conclusions The results demonstrated successful partial replacement of high-protein fish meal using high-quality fermented protein concentrates from plant sources. © 2019 Society of Chemical Industry.

Prebiotics and probiotics improve growth and immune responses in fish. However, their inclusion affects fish when combined with plant proteins is not well studied. The effects of diets with plant concentrates supplemented with yeast Saccharomyces sp. (Y) and/or fructooligosaccharides (FOS) on growth and nonspecific immune responses were determined in rainbow trout. A basal diet (soy, rice protein concentrates, and corn gluten—200, 200, and150 g/kg, respectively) was supplemented with Y (15 g/kg), FOS (5 g/kg), or Y + FOS (15 and 5 g/kg). The basal diet corresponded to the control. Triplicate tanks with 20 fingerlings (initial weight of 1.3 ± 0.1 g; mean ± SE) were fed for 70 days. Higher values of weight gain and specific growth rate were observed in fingerlings fed with Diet Y; the lowest values were observed in the control group. Leucocytes were higher in fish fed with the FOS diet, whereas the burst activity of macrophages was higher in Y‐fed fish. Lysozyme activity in the serum did not show differences among the experimental groups, but significantly higher values were observed in the skin mucus of fish fed Diet Y. The present research shows that the inclusion of yeast with plant protein concentrates improved the growth and burst activity of macrophages in the fingerlings.

Summary To accelerate the isolation of plant protein complexes and study cellular localization and interaction of their components, an improved recombineering protocol is described for simple and fast site‐directed modification of plant genes in bacterial artificial chromosomes (BACs). Coding sequences of fluorescent and affinity tags were inserted into genes and transferred together with flanking genomic sequences of desired size by recombination into Agrobacterium plant transformation vectors using three steps of E. coli transformation with PCR‐amplified DNA fragments. Application of fast‐track recombineering is illustrated by the simultaneous labelling of CYCLIN‐DEPENDENT KINASE D (CDKD) and CYCLIN H (CYCH) subunits of kinase module of TFIIH general transcription factor and the CDKD‐activating CDKF;1 kinase with green fluorescent protein (GFP) and mCherry (green and red fluorescent protein) tags, and a PIPL (His18‐StrepII‐HA) epitope. Functionality of modified CDKF;1 gene constructs is verified by complementation of corresponding T‐DNA insertion mutation. Interaction of CYCH with all three known CDKD homologues is confirmed by their co‐localization and co‐immunoprecipitation. Affinity purification and mass spectrometry analyses of CDKD;2, CYCH, and DNA‐replication‐coupled HISTONE H3.1 validate their association with conserved TFIIH subunits and components of CHROMATIN ASSEMBLY FACTOR 1, respectively. The results document that simple modification of plant gene products with suitable tags by fast‐track recombineering is well suited to promote a wide range of protein interaction and proteomics studies., Significance Statement A PCR‐based BAC‐recombineering protocol accelerating site‐specific modification of plant genes with suitable tags is described and exploited for purification, cellular localization, co‐immunoprecipitation, and mass spectrometry analysis of CDKD;2 and CYCLIN H associated components of TFIIH general transcription factor.

We report the recombinant preparation from Escherichia coli cells of samples of two closely related, small, secreted cysteine‐rich plant peptides: rapid alkalinization factor 1 (RALF1) and rapid alkalinization factor 8 (RALF8). Purified samples of the native sequence of RALF8 exhibited well‐resolved nuclear magnetic resonance (NMR) spectra and also biological activity through interaction with a plant receptor kinase, cytoplasmic calcium mobilization, and in vivo root growth suppression. By contrast, RALF1 could only be isolated from inclusion bodies as a construct containing an N‐terminal His‐tag; its poorly resolved NMR spectrum was indicative of aggregation. We prepared samples of the RALF8 peptide labeled with 15N and 13C for NMR analysis and obtained near complete 1H, 13C, and 15N NMR assignments; determined the disulfide pairing of its four cysteine residues; and examined its solution structure. RALF8 is mostly disordered except for the two loops spanned by each of its two disulfide bridges., PDB Code(s): 6NU4

Post-translational modifications (PTMs) of proteins are central in any kind of cellular signaling. Modern mass spectrometry technologies enable comprehensive identification and quantification of various PTMs. Given the increased numbers and types of mapped protein modifications, a database is necessary that simultaneously integrates and compares site-specific information for different PTMs, especially in plants for which the available PTM data are poorly catalogued. Here, we present the Plant PTM Viewer (http://www.psb.ugent.be/PlantPTMViewer), an integrative PTM resource that comprises approximately 370 000 PTM sites for 19 types of protein modifications in plant proteins from five different species. The Plant PTM Viewer provides the user with a protein sequence overview in which the experimentally evidenced PTMs are highlighted together with an estimate of the confidence by which the modified peptides and, if possible, the actual modification sites were identified and with functional protein domains or active site residues. The PTM sequence search tool can query PTM combinations in specific protein sequences, whereas the PTM BLAST tool searches for modified protein sequences to detect conserved PTMs in homologous sequences. Taken together, these tools help to assume the role and potential interplay of PTMs in specific proteins or within a broader systems biology context. The Plant PTM Viewer is an open repository that allows the submission of mass spectrometry-based PTM data to remain at pace with future PTM plant studies.

BACKGROUND Plant protein-based products such as meat analogues have been receiving attention over the years. However, comparisons of product properties and mechanisms applied in the production of low- and high-moisture meat analogues have not been reported. In this study, the effects of extrusion types (low- and high-moisture extrusion cooking), absence or presence of added wheat gluten, as well as screw speed (150 and 200 rpm) on the physicochemical properties of meat analogues were evaluated. The mechanism of protein texturization of low- and high-moisture meat analogues was studied. RESULTS Extrusion types and addition of wheat gluten had a major influence on physicochemical characteristics which were critical in controlling the fibrous texture of the final product, while screw speed had a minor impact on springiness only (P

A 9‐week feeding trial was conducted using triplicate groups of turbot (6.50 ± 0.01 g) to explore the potential effects of silymarin. Three concentrations of silymarin (100, 200, and 400 mg/kg) were added to the plant protein‐based diet. Fish were randomly distributed into fiberglass tanks (30 fish per tank). The results showed that adding 100 mg/kg silymarin significantly improved the growth performance, with no effects on feed utilization. The antioxidant capacity in the liver was significantly improved in the 100 mg/kg and 200 mg/kg silymarin groups by not only inducing the activities of superoxide dismutase (SOD) and catalase but also increasing the messager RNA (mRNA) expression levels of SOD, glutathione peroxidase, and peroxiredoxin 6. Meanwhile, supplying 100 and 200 mg/kg of silymarin enhanced the heights of villi and enterocytes. Silymarin supplementation reduced the mRNA expression of interleukin‐8 and tumor necrosis factor‐α but induced the expression of transforming growth factor‐β (TGF‐β) in the intestine. These results indicated that silymarin was a potential nutraceutical that could enhance the growth performance and health status of turbot fed in a high plant protein diet. Adding 100 mg/kg silymarin to the plant protein diet achieved optimal performance in turbot.

Cereal yields decrease when grain fill proceeds under conditions of prolonged, moderately elevated temperatures. Endosperm-endogenous processes alter both rate and duration of dry weight gain, but underlying mechanisms remain unclear. Heat effects could be mediated by either abnormal, premature cessation of storage compound deposition or accelerated implementation of normal development. This study used controlled environments to isolate temperature as the sole environmental variable during Zea mays kernel-fill, from 12 days after pollination to maturity. Plants subjected to elevated day, elevated night temperatures (38°C day, 28°C night (38/28°C])) or elevated day, normal night (38/17°C), were compared with those from controls grown under normal day and night conditions (28/17°C). Progression of change over time in endosperm tissue was followed to dissect contributions at multiple levels, including transcriptome, metabolome, enzyme activities, product accumulation, and tissue ultrastructure. Integrated analyses indicated that the normal developmental program of endosperm is fully executed under prolonged high-temperature conditions, but at a faster rate. Accelerated development was observed when both day and night temperatures were elevated, but not when daytime temperature alone was increased. Although transcripts for most components of glycolysis and respiration were either upregulated or minimally affected, elevated temperatures decreased abundance of mRNAs related to biosynthesis of starch and storage proteins. Further analysis of 20 central-metabolic enzymes revealed six activities that were reduced under high-temperature conditions, indicating candidate roles in the observed reduction of grain dry weight. Nonetheless, a striking overall resilience of grain filling in the face of elevated temperatures can be attributed to acceleration of normal endosperm development.

The continuous increase of global consumer's dietary behaviors towards reducing meat consumption due to health benefits, ecological, ethical, and social aspects. Texturized vegetable protein (TVP) transformed from plant protein-based ingredient can impart fibrous structure like muscle meat. However, there is limited information on a comparison of product properties of TVP and meats. In this study, the comparison of physicochemical properties, texture, and structure of TVP and different types of meats (beef, pork, and chicken) were investigated. RESULTS The nitrogen solubility and integrity index, chewiness and cutting strength of TVP were similar to that of the chicken sample compared to other meats. However, water absorption capacity of TVP (2173.84?g?kg?1) was significantly higher than all meat samples (1095.37 to 1653.52?g?kg?1). The color and amino acids of TVP were different from meat samples due to the difference in protein types. TVP showed a fibrous structure with non-uniform air cells. CONCLUSION The study demonstrated that some textural and chemical characteristics of texturized vegetable protein under intermediate moisture extrusion exhibited the most similarity to chicken meat. ? 2018 Society of Chemical Industry

Aquaculture is one of the most thriving animal production sectors, and Nile tilapia (Oreochromis niloticus) farming represents 8% of total finfish culture. However, the industry sustainability depends on the development of cost‐effective and environmental friendly feeds. This study aimed to reduce dietary protein levels in diets for juvenile tilapia and to minimize diet environmental impact while maximizing biological efficiency. A growth trial was performed using five isoenergetic plant protein‐based diets with decreasing levels of crude protein: 360, 340, 320, 300 and 280 g/kg diet (D360, D340, D320, D300 and D280, respectively). Dietary protein utilization was assessed by metabolic trials using a radiolabelled amino acid mixture. Tilapia in all treatments showed similar growth performance and feed intake. Feed conversion ratio was significantly higher in fish fed the D280 than the D360 diet, while no differences were found for other treatments. Protein retention was significantly higher in tilapia fed the D300 than the D360 diet. Amino acid catabolism increased in fish fed the D360 diet, though without significant differences in muscle amino acid retention. This study demonstrates that dietary protein levels can be reduced to 300 g/kg diet without hindering tilapia growth and feed conversion ratio, while reducing environmental nitrogen losses. FCT: UID/Multi/04326/2019/ IF/00482/2014/CP1217/CT0005/ DL57/2016/CP1361/CT0033. info:eu-repo/semantics/publishedVersion

We tested the recent hypothesis that the "fly factor" phenomenon (food currently or previously fed on by flies attracts more flies than the same type of food kept inaccessible to flies) is mediated by bacterial symbionts deposited with feces or regurgitated by feeding flies. We allowed laboratory-reared black blow flies, Phormia regina (Meigen), to feed and defecate on bacterial Luria-Bertani medium solidified with agar, and isolated seven morphologically distinct bacterial colonies. We identified these using matrix-assisted laser desorption/ionization mass spectrometry and sequencing of the 16S rRNA gene. In two-choice laboratory experiments, traps baited with cultures of Proteus mirabilis Hauser, Morganella morganii subsp. sibonii Jensen, or Serratia marcescens Bizio, captured significantly more flies than corresponding control jars baited with tryptic soy agar only. A mixture of seven bacterial strains as a trap bait was more attractive to flies than a single bacterial isolate (M. m. sibonii). In a field experiment, traps baited with agar cultures of P. mirabilis and M. m. sibonii in combination captured significantly more flies than traps baited with either bacterial isolate alone or the agar control. As evident by gas chromatography-mass spectrometry, the odor profiles of bacterial isolates differ, which may explain the additive effect of bacteria to the attractiveness of bacterial trap baits. As "generalist bacteria," P. mirabilis and M. m. sibonii growing on animal protein (beef liver) or plant protein (tofu) are similarly effective in attracting flies. Bacteria-derived airborne semiochemicals appear to mediate foraging by flies and to inform their feeding and oviposition decisions.

Controlling the interactions between plant proteins and polysaccharides can lead to the development of novel electrostatic complexed structures that can give unique functionality. This in turn can broaden the diversity of applications that they may be suitable for. Overwhelmingly in the literature, work and reviews relating to coacervation have involved the use of animal proteins. However, with the increasing demand for plant-based protein alternatives by industry and consumers, a greater understanding of how they interact with polysaccharides is essential to control structure, functionality and applicability. This review discusses the factors governing the nature of protein-polysaccharide interactions, their functional attributes and industrial applications, with special attention given to plant proteins. © 2018 Society of Chemical Industry.

Moringa oleifera leaf (MOL) is an excellent source of high‐quality plant protein. MOL hydrolysate (MOLH) was prepared by enzymatic hydrolysis and ethanol precipitation. The adsorption kinetics of SP‐207 resin for antioxidant peptides from MOLH were studied. The adsorption process for antioxidant peptides on SP‐207 was well described by the pseudo‐second‐order kinetics model. The adsorption was a multi‐molecule layer adsorption process, which was exothermic. The peptide fraction with antioxidant activity (MOLP, 40% ethanol elution fraction) possessing high contents of antioxidant and hydrophobic amino acids was obtained by SP‐207 column chromatography. A total of eight dipeptides including PR, L(I)K, L(I)H, L(I)P, L(I)L(I), GE, VL(I) and PF were identified in gastrointestinal digest of MOLP by UPLC‐QTOF‐MS/MS. The protective effects of MOLP digest and LH on oxidatively damaged erythrocytes by inhibition of MDA formation were comparable to that of GSH, indicating that MOLP could be used as an antioxidative ingredient in functional food.

There is a growing interest in substituting animal proteins with plant protein sources in food systems. A notable example is the replacement of hen egg white (EW) protein, which is used in a wide range of food products because of its excellent foaming characteristics. Here, enzymatically hydrolyzed wheat gluten, which has greater solubility and better foaming properties than wheat gluten itself, was prepared and incorporated in a classical meringue recipe to investigate its potential as a foaming agent. Meringues based on gluten hydrolysates (GHs) had batters with lower density and greater apparent viscosity than those based solely on EW protein. Furthermore, after baking, these GH containing meringues had greater specific volume than those based on EW protein alone and no notable differences in color or texture between the different samples were noted. These outcomes were related to basic insights in the air–water interfacial behavior of GHs obtained in earlier studies. More specifically, the greater foaming capacity of GH than of EW protein solutions was related to their superior meringue batter (density and apparent viscosity) and product (specific volume) properties. While EW protein solutions had better foam stability than GH solutions (in the absence of sugar), this was apparently less relevant for meringue properties, probably due to the very high viscosity of the sugar rich batter, which could obscure differences in the intrinsic foam stabilizing ability of the samples. Replacing animal proteins with plant protein sources in the food industry is desirable from an economic and environmental perspective. Enzymatic hydrolysis serves as a tool to improve the foaming properties of water‐insoluble wheat gluten proteins. We conclude that wheat gluten hydrolysates can be a valid functional alternative for egg white proteins in meringues, and possibly other food systems.

Lupine (Lupinus angustifolius L.) protein (in wholemeal and protein isolates) was biodegraded using Pediococcus acidilactici in submerged and solid‐state fermentation conditions. The changes in the molecular weight of lupine protein fractions, amino acid (AA) profile, biogenic amine formation, antimicrobial and antioxidant properties, and protein digestibility in vitro and in vivo (in Wistar rats) were evaluated. After biotreatment, lower molecular weight peptides (from 10 to 20 kDa) were established, and the free AA content increased. Biodegradation improved the antioxidant properties, modulated the antimicrobial properties, and led to higher in vitro and in vivo digestibility and functionality of the lupine in treated rats (significant increase in body weight of Wistar rats, and increased acetic acid concentration and lowered Escherichia coli count in the caecum). Overall, the biodegradation of lupine protein can transform the plant protein, producing enhanced functionality and bioavailable products.

Cowpea (Vigna unguiculata) is a legume consumed as a high-quality plant protein source in many parts of the world. High protein and carbohydrate contents with a relatively low fat content and a complementary amino acid pattern to that of cereal grains make cowpea an important nutritional food in the human diet. Cowpea has gained more attention recently from consumers and researchers worldwide as a result of its exerted health beneficial properties, including anti-diabetic, anti-cancer, anti-hyperlipidemic, anti-inflammatory and anti-hypertensive properties. Among the mechanisms that have been proposed in the prevention of chronic diseases, the most proven are attributed to the presence of compounds such as soluble and insoluble dietary fiber, phytochemicals, and proteins and peptides in cowpea. However, studies on the anti-cancer and anti-inflammatory properties of cowpea have produced conflicting results. Some studies support a protective effect of cowpea on the progression of cancer and inflammation, whereas others did not reveal any. Because there are only a few studies addressing health-related effects of cowpea consumption, further studies in this area are suggested. In addition, despite the reported favorable effects of cowpea on diabetes, hyperlipidemia and hypertension, a long-term epidemiological study investigating the association between cowpea consumption and diabetes, cardiovascular disease and cancer is also recommended. © 2018 Society of Chemical Industry.

LlPR‐10.2B, a Pathogenesis‐related class 10 (PR‐10) protein from yellow lupine (Lupinus luteus) was crystallized in complex with melatonin, an emerging important plant regulator and antioxidant. The structure reveals two molecules of melatonin bound in the internal cavity of the protein, plus a very well‐defined electron density near the cavity entrance, corresponding to an unknown ligand molecule comprised of two flat rings, which is most likely a product of melatonin transformation. In a separate LlPR‐10.2B co‐crystallization experiment with an equimolar mixture of melatonin and trans‐zeatin, which is a cytokinin phytohormone well recognized as a PR‐10‐binding partner, a quaternary 1 : 1 : 1 : 1 complex was formed, in which one of the melatonin‐binding sites has been substituted with trans‐zeatin, whereas the binding of melatonin at the second binding site and binding of the unknown ligand are undisturbed. This unusual complex, when compared with the previously described PR‐10/trans‐zeatin complexes and with the emerging structural information about melatonin binding by PR‐10 proteins, provides intriguing insights into the role of PR‐10 proteins in phytohormone regulation in plants, especially with the involvement of melatonin, and implicates the PR‐10 proteins as low‐affinity melatonin binders under the conditions of elevated melatonin concentration. DATABASES: Atomic coordinates and processed structure factors corresponding to the final models of the LlPR‐10.2B/melatonin and LlPR‐10.2B/melatonin + trans‐zeatin complexes have been deposited with the Protein Data Bank (PDB) under the accession codes 5MXB and 5MXW. The corresponding raw X‐ray diffraction images have been deposited in the RepOD Repository at the Interdisciplinary Centre for Mathematical and Computational Modelling (ICM) of the University of Warsaw, Poland, and are available for download with the following Digital Object Identifiers (DOI): https://doi.org/10.18150/repod.9923638 and https://doi.org/10.18150/repod.6621013.

Sedentary plant-parasitic cyst nematodes are obligate biotrophs that infect the roots of their host plant. Their parasitism is based on the modification of root cells to form a hypermetabolic syncytium from which the nematodes draw their nutrients. The aim of this study was to identify nematode susceptibility genes in Arabidopsis thaliana and to characterize their roles in supporting the parasitism of Heterodera schachtii. By selecting genes that were most strongly upregulated in response to cyst nematode infection, we identified HIPP27 (HEAVY METAL-ASSOCIATED ISOPRENYLATED PLANT PROTEIN 27) as a host susceptibility factor required for beet cyst nematode infection and development. Detailed expression analysis revealed that HIPP27 is a cytoplasmic protein and that HIPP27 is strongly expressed in leaves, young roots and nematode-induced syncytia. Loss-of-function Arabidopsis hipp27 mutants exhibited severely reduced susceptibility to H. schachtii and abnormal starch accumulation in syncytial and peridermal plastids. Our results suggest that HIPP27 is a susceptibility gene in Arabidopsis whose loss of function reduces plant susceptibility to cyst nematode infection without increasing the susceptibility to other pathogens or negatively affecting the plant phenotype.

Based on the importance of tambaqui, Colossoma macropomum, for Latin American aquaculture and the digestibility of minerals for the production of sustainable aquafeeds, we designed a series of trials to determine the apparent digestibility coefficients (ADCs) of phosphorus, calcium, magnesium, manganese, and zinc from six protein sources: soybean meal (SBM), corn gluten meal 60 (CGM60), cottonseed meal 40, fishmeal (FM), poultry byproduct meal (PBM), and meat and bone meal (MBM); four cereal grain products: corn, wheat middlings, broken rice (BR), and rice bran (RB); and dicalcium phosphate (DCP). Considerable variation in the ADCs of minerals was observed among the feed ingredients. In general, CGM60, PBM, and RB tended to show the highest ADC values, while SBM, MBM, DCP, and BR showed the lowest ADC values. ADC‐P was markedly lower in animal protein sources and the phosphate source (DCP), while high P digestibility was observed for plant protein sources and cereal grain products. Interestingly, tambaqui seems to be able to digest and absorb minerals from plant ingredients more efficiently than animal proteins and DCP. In light of the correlation between nutrient levels and the ADCs of minerals, physiological mechanisms that regulate mineral uptake, and the nutritional ecology of the species, we hypothesize that tambaqui are able to digest minerals from plant proteins with high efficiency.