Bioavailability Of Methionine Research Articles

Comparative life cycle assessment for the sustainable production of fermentation-based L-methionine

Methionine, essential for human and animal growth, faces increasing demand, contributing significantly to greenhouse gas emissions through animal digestion and nitrogen excretion. This study introduces L-methionine (L-Met) produced biologically from CJ CheilJedang Corp., offering a sustainable alternative to the conventional petroleum-based DL-methionine (DL-Met) due to its higher bioavailability and reduced environmental impact. One of the most important aspects for the sustainable lifecycle of L-Met is to reduce environmental impact during the production stage. Consequently, the aim of this study is to evaluates the environmental impact of L-Met and its environmentally improved product, L-Met Eco, through a life cycle assessment compared to DL-Met. We employed scenario analysis to consider uptake CO2 by bio-based feedstock, bioavailability of methionine, and system expansion of co-products. Our findings indicate that L-Met and L-Met Eco have lower global warming potentials of 0.92 and 0.79 kg CO2/kg Met, respectively, than DL-Met (2.60−3.32 kg CO2/kg Met). Sensitivity analysis further suggests that optimizing renewable energy use and production location can significantly enhance the sustainability of L-Met production. This comprehensive study offers valuable insights for stakeholders in the bio-based material sector, promoting environmentally sustainable practices.

Identification of β-aspartic semialdehyde and homocysteine as major reaction products of riboflavin-sensitized photooxidation of peptide-bound methionine

Methionine is an essential amino acid for mammals and it is limiting for monogastric animals. It can be oxidized easily by UV light. This could influence the bioaccessibility and bioavailability of methionine. In this work, the photosensitized degradation of peptide-bound methionine in the presence of riboflavin was investigated in a model system. Capillary electrophoresis was employed to analyze the time course of the degradation. The products were identified by liquid chromatography coupled to mass spectrometry (LC–MS/MS). Benzoyl methionine was degraded by 50% during UV irradiation in the presence of riboflavin after 5.0 min with 10 mol% riboflavin and 6.4 min with 3 mol% riboflavin. Homocysteine (16–20 mol%) and β-aspartic semialdehyde (ca. 30 mol%) were found as major degradation products next to methionine sulfoxide (ca. 25 mol%). A smaller molar ratio of riboflavin led to a higher formation of aspartic semialdehyde. The formation of homocysteine was paralleled by the formation of formaldehyde. Furthermore, the experiment was transferred to small peptides, which showed the analogous degradation products of peptide-bound methionine.

129 Protein and Amino Acid Modifications During Extrusion

Abstract Extrusion cooking is a high-temperature, short-time process and the foremost technique to produce attractive, nutritious and safe pet foods. As extruded foods are often routinely fed throughout the entire life of pet dogs and cats, it is important to understand the factors that influence protein quality. Protein quality, i.e. the quantity and bioavailability of amino acids, depends on the ingredients and the combination of interrelated process parameters including moisture, temperature, pressure, and mechanical shear. Few studies on the effects of extrusion of pet foods are available and both positive and negative effects on the bioavailability of proteins and amino acids were noted. Effects can in part relate to changes in the food matrix rendering proteins available for digestive enzymes. Moreover, various molecular transformations and chemical reactions can occur including denaturation, aggregation, Maillard reaction, cross-linking, oxidation, and racemisation. Denaturation of proteins is likely not important for facilitating digestion, but denaturation of enzyme inhibitors is key for plant-based pet foods as well as the reduction or elimination of non-protein anti-nutritional factors. It is clear that both ingredient selection and extrusion process parameters impact changes in quantities of bioavailable lysine via the Maillard reaction. The supply of reactive lysine can be insufficient for growing dogs and should be monitored. Bioavailability of methionine and cysteine can also be compromised due to oxidation during processing but is currently understudied. As with studies on lysine, specific analytical procedures should be applied to prevent overestimation of methionine and cysteine in pet foods. In conclusion, the extrusion is a complex process that can impact protein quality in many ways and to various degrees and more studies are required to advance our understanding of the exact underlying molecular mechanisms and to assure the quality of pet foods.

Bioavailable Methionine Assessed Using the Indicator Amino Acid Oxidation Method Is Greater When Cooked Chickpeas and Steamed Rice Are Combined in Healthy Young Men

In general, pulse protein is limiting in the indispensable amino acid methionine, and antinutritional factors in pulses can affect methionine bioavailability. Complementation with grains such as rice can improve pulse protein quality, but knowledge of methionine bioavailability in pulses and grains is necessary to correct for available methionine when planning and assessing dietary protein intake. The study objectives were to determine the bioavailability of methionine in rice and chickpeas separately and to assess the effect of complementation of chickpeas and rice. Eleven healthy young men (<30 y, BMI <25 kg/m2) were studied in a repeated-measures design using the indicator amino acid oxidation (IAAO) method, with l-[1-13C]phenylalanine as the indicator. Each received 7 or 10 methionine intakes in random order: 4 intakes of l-methionine-0.5, 1, 2, and 3 mg⋅kg-1⋅d-1 (reference diet); 3 intakes of methionine from rice and from chickpeas; and 3 intakes from the mixed meal of chickpeas plus rice (test diets). The bioavailability of methionine and the effect of complementation were assessed by comparing the IAAO response to varying intakes of methionine in rice, in cooked Canadian chickpeas, and in rice plus chickpeas combined compared with the IAAO response to l-methionine intakes in the reference protein (crystalline amino acid mixture patterned after egg protein) using the slope ratio method. The bioavailability of methionine from rice and from chickpeas was 100% and 63%, respectively. Complementation of cooked chickpeas with rice decreased the oxidation of l-[1-13C]phenylalanine by up to 14% (P<0.05), suggesting an improved protein quality of the combined chickpeas plus rice protein. When chickpeas are the main protein source in the diet of young adult men, the combination of rice and chickpeas in a 3:1 ratio is recommended to improve dietary protein quality. This trial was registered at clinicaltrials.gov as NCT03339154 and NCT03674736.

To Supplement or Not to Supplement: A Metabolic Network Framework for Human Nutritional Supplements

Flux balance analysis and constraint based modeling have been successfully used in the past to elucidate the metabolism of single cellular organisms. However, limited work has been done with multicellular organisms and even less with humans. The focus of this paper is to present a novel use of this technique by investigating human nutrition, a challenging field of study. Specifically, we present a steady state constraint based model of skeletal muscle tissue to investigate amino acid supplementation's effect on protein synthesis. We implement several in silico supplementation strategies to study whether amino acid supplementation might be beneficial for increasing muscle contractile protein synthesis. Concurrent with published data on amino acid supplementation's effect on protein synthesis in a post resistance exercise state, our results suggest that increasing bioavailability of methionine, arginine, and the branched-chain amino acids can increase the flux of contractile protein synthesis. The study also suggests that a common commercial supplement, glutamine, is not an effective supplement in the context of increasing protein synthesis and thus, muscle mass. Similar to any study in a model organism, the computational modeling of this research has some limitations. Thus, this paper introduces the prospect of using systems biology as a framework to formally investigate how supplementation and nutrition can affect human metabolism and physiology.

Potential for development of an Escherichia coli-based biosensor for assessing bioavailable methionine: a review.

Methionine is an essential amino acid for animals and is typically considered one of the first limiting amino acids in animal feed formulations. Methionine deficiency or excess in animal diets can lead to sub-optimal animal performance and increased environmental pollution, which necessitates its accurate quantification and proper dosage in animal rations. Animal bioassays are the current industry standard to quantify methionine bioavailability. However, animal-based assays are not only time consuming, but expensive and are becoming more scrutinized by governmental regulations. In addition, a variety of artifacts can hinder the variability and time efficacy of these assays. Microbiological assays, which are based on a microbial response to external supplementation of a particular nutrient such as methionine, appear to be attractive potential alternatives to the already established standards. They are rapid and inexpensive in vitro assays which are characterized with relatively accurate and consistent estimation of digestible methionine in feeds and feed ingredients. The current review discusses the potential to develop Escherichia coli-based microbial biosensors for methionine bioavailability quantification. Methionine biosynthesis and regulation pathways are overviewed in relation to genetic manipulation required for the generation of a respective methionine auxotroph that could be practical for a routine bioassay. A prospective utilization of Escherichia coli methionine biosensor would allow for inexpensive and rapid methionine quantification and ultimately enable timely assessment of nutritional profiles of feedstuffs.

Determination of Sulfur Amino Acids in Foods as Related to Bioavailability

During the processing of feedstuffs and foods, methionine can be oxidized to methionine sulfoxide and methionine sulfone, and cysteine can be oxidized to cysteic acid. Methionine sulfone and cysteic acid are nutritionally unavailable, but methionine sulfoxide can be utilized, at least to some degree. The degree of utilization depends on the levels of methionine, cysteine, and methionine sulfoxide in the diet, but there is no consensus in the literature on the quantitative impact of these dietary constituents on methionine sulfoxide utilization. Methionine and cysteine are most often determined after quantitative oxidation to methionine sulfone and cysteic acid, respectively, using performic acid oxidation prior to hydrolysis. However, this method may overestimate the methionine content of processed foods, as it will include any methionine sulfoxide and methionine sulfone present. A selection of analytical methods has been developed to allow the separate determination of the 3 oxidized forms of methionine, the merits of which are discussed in this review. An additional consideration for determining methionine and cysteine bioavailability is that not all dietary methionine and cysteine is digested and absorbed from the small intestine. Selected methods designed to determine the extent of digestion and absorption are discussed. Finally, a concept for a new assay for determining methionine bioavailability, which includes determining the digestibility of methionine and methionine sulfoxide as well as the utilization of methionine sulfoxide, is presented.

RAPID BACTERIAL‐BASED BIOASSAYS FOR QUANTIFYING METHIONINE BIOAVAILABILITY IN ANIMAL FEEDS: A REVIEW

ABSTRACT Animal and digestibility assays are the current method to quantitate methionine bioavailability. However, in addition to the costs, the variability and the time response can be hindered by a variety of factors. Ultimately, there is considerable need to develop and to optimize rapid, inexpensive in vitro assays to accurately and consistently measure the amount of digestible methionine that exists in feeds and to correlate them with in vivo assays. Attaining these objectives will allow for an inexpensive and rapid methionine assessment and will ultimately enable a timely assessment of the nutritional profiles of feedstuffs.

Development of a method for measuring lysine and methionine bioavailability in rumen-protected products for cattle

2. The plasma free amino acid dose-response technique: A proposed methodology for determining lysine relative bioavailability of rumen-protected lysine supplements N.L. Whitehouse, C.G. Schwab, A.F. Brito Journal of Dairy Science CrossRef

In Vitro Digestibility of Albumin Proteins from Phaseolus vulgaris L. Effect of Chemical Modification

The in vitro digestibility of albumins from Phaseolus vulgaris was studied. The extent of hydrolysis of native albumins was low (32%), and when they were heated (99 °C for 30 min), it was reduced even more, to 20%. Chemical deglycosylation increased proteolysis of both native (44.4%) and heated (30.7%) albumins. Reversible blockage of the ε-amino groups of lysine residues during heating resulted in an extent of hydrolysis (29.8%) similar to that of native albumins. Heating (99 oC for 30 min) caused formation of new disulfide bonds and incomplete inactivation of trypsin inhibitors, which was attained only by autoclaving for a prolonged time (2 h). A digestibility similar to that of casein was only achieved during a 27 h prolonged pepsin−pancreatin hydrolysis of chemically denatured and deglycosylated albumins. Primary structure, native conformation, heat-stable trypsin inhibitors, steric hindrance imposed by carbohydrates, and chemical reactions induced by heating seem to be major factors responsible for the low digestibility of albumins. Keywords: Phaseolus vulgaris; albumin proteins; digestibility; methionine bioavailability; chemical modification

Methionine-containing proteins in twoPhaseolus vulgaris cultivars with different methionine bioavailabilities

The full utilization of legumes as human food is limited by a deficiency of sulfur amino acids, low protein digestibility, low methionine bioavailability and the presence of anti-nutritional factors. A new cultivar of Phaseolus vulgaris (Carioca 80) has 56.8% available methionine, compared with 29.3% availability in the parent cultivar Carioca. The total methionine content, denaturing gel electrophoretic patterns of methionine-containing proteins, and the percentage of phaseolins (the major storage proteins in Phaseolus) relative to the total protein are similar in the two cultivars. Although the digestibility of the two cultivars is similar, the increased biological value of Carioca 80 may indicate that there are differences in overall bean composition that affect protein hydrolysis and utilization. We suggest the tentative explanation that this is due to differences in the distribution of methionine in the methionine-containing proteins of the two cultivars.

Protein nutritive value of a new cultivar of bean (Phaseolus vulgaris L.)

The objective of this paper was to report the proximate composition, amino acid profile, and protein nutritive value of a new cultivar of dry bean (Carioca 80), which has been developed by crossing the Brazilian cultivar Carioca with the variety Cornell 49-242. In addition to improved productivity and resistance to rust and anthracnosis, the new cultivar presented methionine bioavailability of 57%, digestibility around 70%, and biological value from 75% to 80%

Bioavailability of methionine in some tripeptides occurring in dietary proteins as determined by rat growth

Relative bioavailability of methionine (L-Met=100) in tripeptides found in β-casein (Ala-Met-Ala; Ala-D-Met-Ala; Val-Met-Phe; Val-D-Met-Phe) and in soy glycine (Thr-Met-Arg; Thr-D-Met-Arg; Thr-Met-Lys) was determined by the rat growth method using net protein ratio (NPR) as the performance index. Crystalline D-Met was completely available to the growing rat, but in the tripeptide form, D-Met (0–45%) was considerably less available than L-Met (38–71%). The bioavailability of Met was also influenced by the side chain of the adjacent amino acids. Met in the tripeptides with the bulky amino acids (Val-Met-Phe, Thr-Met-Arg, Thr-Met-Lys) was less available than in the unhindered tripeptide (Ala-Met-Ala). D-Met in the hindered tripeptides (Val-D-Met-Phe, Thr-D-Met-Arg) did not support rat growth at all.

Covalent attachment of amino acids to casein. 2. Bioavailability of methionine and N-acetylmethionine covalently linked to casein.

Covalent attachment of amino acids to casein. 2. Bioavailability of methionine and N-acetylmethionine covalently linked to casein.