Protein Biofortified Sorghum: Effect of Processing into Traditional African Foods on Their Protein Quality

Taylor, Janet; Taylor, John R.N.

doi:10.1021/jf104006v

Cited by 32 publications

(35 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Also, the total protein content of the TG lines fell within the normal range for sorghum (5). Hence, the suppression of synthesis of these kafirin sub-classes also did not result in substantial reduction in total protein content.…”

Section: Resultsmentioning

confidence: 79%

See 1 more Smart Citation

Transgenic Sorghum with Altered Kafirin Synthesis: Kafirin Solubility, Polymerization, and Protein Digestion

Silva

Taylor

2011

J. Agric. Food Chem.

Self Cite

View full text Add to dashboard Cite

Transgenic sorghum (TG) lines with altered kafirin synthesis, particularly suppression of gamma-kafirin synthesis, and improved protein quality have been developed. The proportion of kafirin extracted with 60% tert-butanol alone was greatly increased in the TG lines. However, the total amount of kafirin remained unchanged.Further, in the TG lines, the kafirin was much less polymerized by disulfide bonding.There was also evidence of compensatory synthesis of other kafirin proteins. Cooked protein digestibility was increased in the TG form, even after removal of interfering starch.The TG protein bodies were intermediate in appearance between the normal type and the invaginated high digestibility mutants. Hence, the increased protein digestibility of these TG lines is probably related to their lower levels of disulfide-bonded kafirin polymerization, allowing better access of proteases. This work appears to confirm that disulfide bond formation in kafirin is responsible for the reduced protein digestibility of cooked sorghum.

show abstract

Section: Resultsmentioning

confidence: 79%

“…60%), improved Lysine Score (0.5) and protein digestibility corrected amino acid score (0.4) (5). The improved protein quality traits are maintained when the TG sorghum is used to produce porridge, a major African staple food (6) and a wide range of other sorghum food products (5).…”

Section: Africa Biofortified Sorghum (Abs) Project Under the Bill Anmentioning

confidence: 99%

Transgenic Sorghum with Altered Kafirin Synthesis: Kafirin Solubility, Polymerization, and Protein Digestion

Silva

Taylor

2011

J. Agric. Food Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Da Silva et al (2011b) showed that these transgenic sorghums also had a much reduced proportion of disulphide bond cross-linked type kafirin. Dough-based baked products including biscuits and flatbreads of comparable quality to those from normal sorghum could be produced from these transgenic sorghums (Taylor and Taylor, 2011). However, their actual dough properties and leavened bread-making quality were not investigated.…”

Section: Genetic Modification Of Storage Protein Expressionmentioning

confidence: 99%

Functionality of the storage proteins in gluten-free cereals and pseudocereals in dough systems

Taylor

Campanella

et al. 2016

Journal of Cereal Science

Self Cite

View full text Add to dashboard Cite

The dough functionality of the storage proteins in "gluten-free" grains has been studied for almost 25 years. Zein, maize prolamin, when isolated as α-zein can form a wheat gluten-like visco-elastic dough when mixed with water above its glass transition temperature. There is good evidence that its dough-forming properties are related to a change in protein conformation from α-helix to β-sheet and association of the molecules into fibrils. Stabilisation of β-sheet structure and visco-elasticity can be enhanced by inclusion of a co-protein. No other isolated cereal or pseudocereal storage protein has been shown to form a visco-elastic dough. Many treatments have been applied to improve "gluten-free" storage protein functionality, including acid/base, deamidation, cross-linking by oxidising agents and transglutaminase, proteolysis, disulphide bond reduction and high pressure treatment. Such treatments have some limited positive benefits on batter-type dough functionality, but none is universally effective and the effects seem to be dependent on the composition and structure of the particular storage protein. Research into mutants where prolamin synthesis is altered appears to be promising in terms of improved dough functionality and scientific understanding. Research into how treatments affect the functionality and structure of isolated storage proteins from "gluten-free" grains other than maize is required.2

show abstract

“…Nonkafirins, including albumins, globulins, and glutelins, are also thought to play a role in starch storage, forming a shell around protein bodies, thus providing structure in the protein-starch matrix (68,69). These proteins, in addition to the kafirins, influence grain quality, particularly nutritional value, and their further characterisation and association with grain biochemistry is warranted as a means to mitigate grain quality issues.…”

Section: Biochemical Analysesmentioning

confidence: 99%

“…The proportion of soluble to insoluble proteins in the matrix determines the access of enzymes to starch and oligo-and polysaccharides (67). Non-kafirins provide a readily accessible source of nitrogen and carbon to the embryo during germination and also play an important secondary role in seed storage, providing structure to the protein-starch matrix (68,69). The successful development and germination of maize null glb mutants suggests that globulins are not strictly required for normal seed function.…”

Section: The Protein-starch Matrixmentioning

confidence: 99%

Grain Proteomics of Sorghum: Improving Digestibility, Nutritional Quality and Starch Conversion to Ethanol

Cremer¹

View full text Add to dashboard Cite

Sorghum is an important food staple in rural Asia, India and Africa and a major feedstock in developed countries. Originating in the semi-arid African savannah, sorghum is well adapted to drought prone environments and produces more biomass per unit water than maize. Extensive variability exists within the sorghum gene pool creating a diversity of plant forms with many commercial and industrial applications. Sorghum, provides an alternative to grain crops with greater irrigation and fertiliser requirements, such as maize, however, the grain is generally less digestible, especially upon cooking, due to extensive disulphide cross-linking among sulphur-rich storage proteins in the protein-starch matrix. This reduces the accessibility of proteolytic enzymes to starch, decreasing palatability and nutritional value, and resulting in the need for increased processing.The commercial value of cereals is largely determined by the chemistry of the protein-starch matrix.Located on the periphery of storage protein bodies, cysteine-rich β-and γ-kafirins prevent enzymatic access to internally positioned α-kafirins and to starch. The development of mutants is an efficient approach for studying genetic regulation of protein biosynthesis and compartmentalisation and shows how changes in protein profile affect the physical characteristics of the seed. An integrated proteomic approach was employed to characterise 28 sorghum lines with allelic variation at the kafirin loci, including three β-kafirin null mutants, in order to determine the effects of kafirin genetic diversity on the expression of storage proteins.High performance liquid chromatography (HPLC) and capillary electrophoresis were employed to profile water/salt-and alcohol-soluble protein fractions, revealing a wide range of diversity in protein content across the genotypes. Peak profiles were similar among β-kafirin null lines but different to normal lines, with a significant reduction in alcohol-soluble protein and the disappearance of a major set of protein peaks. The relative content of sequentially extracted soluble, insoluble and residual proteins was measured using RP-HPLC to evaluate the degree of crosslinking among storage proteins in the seed. High levels of insoluble and residual protein were associated with reduced digestibility.Gel-based separation of seed proteins and subsequent identification with tandem mass spectrometry identified a range of redox-active proteins affecting storage protein biochemistry. Multiple protein fractions were analysed across the β-kafirin null line QL12 and wild-type line 296B. The redox states of endosperm proteins, of which kafirins are a subset, have been shown to impact on quality traits in addition to the expression of proteins. Thioredoxin, active in the processing of storage v proteins at germination, has reported impacts on grain digestibility and was differentially expressed across the genotypes. A range of putative uncharacterised sorghum proteins regulating the folding and disulphide pairing of storage proteins ...

show abstract

Protein Biofortified Sorghum: Effect of Processing into Traditional African Foods on Their Protein Quality

Cited by 32 publications

References 32 publications

Transgenic Sorghum with Altered Kafirin Synthesis: Kafirin Solubility, Polymerization, and Protein Digestion

Transgenic Sorghum with Altered Kafirin Synthesis: Kafirin Solubility, Polymerization, and Protein Digestion

Functionality of the storage proteins in gluten-free cereals and pseudocereals in dough systems

Grain Proteomics of Sorghum: Improving Digestibility, Nutritional Quality and Starch Conversion to Ethanol

Contact Info

Product

Resources

About