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John R N Taylor - One of the best experts on this subject based on the ideXlab platform.
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novel biofortified sorghum lines with combined waxy high amylopectin starch and high protein Digestibility traits effects on endosperm and flour properties
Journal of Cereal Science, 2015Co-Authors: Mohammed S M Elhassan, Naushad M Emmambux, Dirk B Hays, Gary C Peterson, John R N TaylorAbstract:Abstract Novel biofortified sorghum lines have been developed with both waxy starch (high amylopectin) and high protein Digestibility traits. Eight sorghum lines with different combinations of waxy, non-waxy, high- and normal-protein Digestibility traits were studied in relation to flour properties. Lines with the high protein Digestibility trait had loosely packed starch granules and floury endosperm, irrespective of whether they were waxy or non-waxy. In terms of thermal properties, combined waxy-high Digestibility lines had the highest onset endothermic temperature as well as endothermic energy compared to non-waxy, normal protein Digestibility lines. The waxy-high protein Digestibility lines had higher paste viscosity and formed much softer and less sticky pastes than the non-waxy, normal protein Digestibility lines. Flours of the combined waxy-high protein Digestibility sorghum lines had much higher solubility than the non-waxy- normal protein Digestibility lines. At 30 °C flour solubility, waxy-high protein Digestibility sorghum lines flour was similar to commercial wheat bread flours. The high flour solubility, high pasting viscosity and soft paste of sorghum lines with combined waxy and high protein Digestibility traits indicate that their flours may have better properties for making dough-based food products than normal non-waxy, normal protein Digestibility sorghums.
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Co-suppression of synthesis of major α-kafirin sub-class together with γ-kafirin-1 and γ-kafirin-2 required for substantially improved protein Digestibility in transgenic sorghum
Plant Cell Reports, 2014Co-Authors: Andile W. Grootboom, Nompumelelo L. Mkhonza, Zodwa Mbambo, Martha M. O’kennedy, Laura S. Silva, Rachel Chikwamba, Janet Taylor, John R N Taylor, Luke MehloAbstract:Key message Co-suppressing major kafirin sub-classes is fundamental to improved protein Digestibility and nutritional value of sorghum. The improvement is linked to an irregularly invaginated phenotype of protein bodies. Abstract The combined suppression of only two genes, γ kafirin-1 (25 kDa) and γ-kafirin-2 (50 kDa), significantly increases sorghum kafirin in vitro Digestibility. Co-suppression of a third gene, α-kafirin A1 (25 kDa), in addition to the two genes increases the Digestibility further. The high-Digestibility trait has previously only been obtained either through the co-suppression of six kafirin genes (α-A1, 25 kDa; α-B1, 19 kDa; α-B2, 22 kDa; γ-kaf1, 27 kDa; γ-kaf 2, 50 kDa; and δ-kaf 2, 18 kDa) or through random chemical-induced mutations (for example, the high protein Digestibility mutant). We present further evidence that suppressing just three of these genes alters kafirin protein cross-linking and protein body microstructure to an irregularly invaginated phenotype. The irregular invaginations are consistent with high pepsin enzyme accessibility and hence high Digestibility. The approach we adopted towards increasing sorghum protein Digestibility appears to be an effective tool in improving the status of sorghum as a principal supplier of energy and protein in poor communities residing in marginal agro-ecological zones of Africa.
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use of γ irradiation to alleviate the poor protein Digestibility of sorghum porridge
Food Chemistry, 2005Co-Authors: E N Fombang, John R N Taylor, Carl Moses Mbofung, Amanda MinnaarAbstract:One limitation to the use of sorghum as a food is that its proteins become more indigestible on wet-cooking, primarily through the formation of disulphide-linked enzymatically resistant protein polymers. Irradiation can modify bonds involved in protein secondary structure. The effects of irradiation (10 and 50 kGy) of dry and wet sorghum and maize flours on the Digestibility and solubility of their proteins, when further cooked into porridge, were investigated. Irradiation of sorghum flour, followed by cooking, alleviated the adverse effect of cooking on sorghum protein Digestibility. Maize porridge Digestibility was unaffected by irradiation of dry flour but decreased with wet-irradiation. Increase in Digestibility was not accompanied by an increase in protein solubility, suggesting that it was probably related to modification of protein structure, allowing better access to proteolytic enzymes. Maillard reactions and protein aggregation, at high doses, negatively affected Digestibility. Polyphenols influenced the effects of irradiation.
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alleviation of the adverse effect of cooking on sorghum protein Digestibility through fermentation in traditional african porridges
International Journal of Food Science and Technology, 2002Co-Authors: Janet Taylor, John R N TaylorAbstract:Cooking sorghum is well known to reduce its protein Digestibility. In southern Africa fermented sorghum porridges are commonly consumed. Knowledge is lacking as to how their preparation affects sorghum protein Digestibility. Five sorghum varieties of varied origin were fermented using traditional semi-solid state fermentation. In vitro protein Digestibility and a new index, in vitro insoluble protein Digestibility, were measured. Both increased during fermentation, generally within the first day, coinciding with a strong decrease in pH. The increase in insoluble protein Digestibility suggests fermentation causes structural changes in the sorghum storage proteins (prolamins and glutelins), making them more accessible to pepsin attack. Wet cooking during porridge-making greatly reduced protein Digestibility. Combining fermentation with cooking, either fermenting then cooking or cooking then fermenting, significantly improved protein Digestibility over wet cooking alone. Thus natural fermentation, as applied in traditional African porridge preparation is an effective method of improving the protein Digestibility of cooked sorghum.
M S Allen - One of the best experts on this subject based on the ideXlab platform.
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effects of fatty acid supplements on ruminal and total tract nutrient digestion in lactating dairy cows
Journal of Dairy Science, 2006Co-Authors: Kevin John Harvatine, M S AllenAbstract:Saturated and unsaturated fatty acid supplements (FS) were evaluated for effects on ruminal digestion kinetics, and ruminal and postruminal nutrient digestion. Eight early lactation ruminally and duodenally cannulated cows (77 ± 12 days in milk, mean ± SD) were used in a replicated 4 × 4 Latin square design experiment with 21-d periods. Treatments were control and a linear substitution of 2.5% fatty acids from supplemented saturated FS (SAT; prilled, hydrogenated free fatty acids) for partially unsaturated FS (UNS; calcium soaps of long-chain fatty acids). All rations contained identical forage and concentrate components including 37.2% forage and 13.5% cottonseed. Saturated FS linearly decreased ruminal Digestibility of dry matter and organic matter and linearly decreased ruminal neutral detergent fiber (NDF) Digestibility. The reduction in ruminal NDF Digestibility was because of a linear decrease in digestion rate and a linear increase in passage rate of potentially digestible NDF with increasing saturated FS. Total tract Digestibility of NDF was not different between treatments because of compensatory postruminal digestion. Ruminal fatty acid and C18 fatty acid Digestibility tended to increase linearly with increasing unsaturated FS, and postruminal C18 fatty acid Digestibility decreased with increasing saturated FS. Saturated FS linearly decreased ruminal organic matter Digestibility and decreased intestinal long-chain fatty acid Digestibility, although differences in fatty acid Digestibility may be partially explained by fatty acid intake.
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evaluation of the importance of the Digestibility of neutral detergent fiber from forage effects on dry matter intake and milk yield of dairy cows
Journal of Dairy Science, 1999Co-Authors: M S AllenAbstract:Effects of the Digestibility of neutral detergent fiber (NDF) from forage on performance of dairy cows were evaluated statistically using treatment means for 13 sets of forage comparisons reported in the literature. All comparisons reported significant differences in NDF digestibilities of forages in situ or in vitro. Treatment means were blocked by study or by additional factorial treatment within a study to remove variation among experiments. The statistical model included random effect of block, fixed factorial effect of NDF Digestibility (high or low), and dietary NDF concentration as a covariate. Enhanced NDF Digestibility of forage significantly increased dry matter intake (DMI) and milk yield. A one-unit increase in NDF Digestibility in vitro or in situ was associated with a 0.17-kg increase in DMI and a 0.25-kg increase in 4% fat-corrected milk. Differences in NDF Digestibility between treatments were greater when measured in vitro or in situ than when measured in vivo. Digestibility of NDF in vitro or in situ might be a better indicator of DMI than NDF Digestibility in vivo because forages with high in vitro or in situ NDF digestibilities might have shorter rumen retention times, allowing greater DMI at the expense of NDF Digestibility in vivo. Digestibility of NDF is an important parameter of forage quality.
J L Yanez - One of the best experts on this subject based on the ideXlab platform.
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effect of phytase and xylanase supplementation or particle size on nutrient Digestibility of diets containing distillers dried grains with solubles cofermented from wheat and corn in ileal cannulated grower pigs
Journal of Animal Science, 2011Co-Authors: J L Yanez, E Beltranena, M Cervantes, R T ZijlstraAbstract:Nutrient Digestibility in distillers dried grains with solubles (DDGS) is limited by physical constraints such as particle size and by biochemical limitations such as phytate and fiber or nonstarch polysaccharides (NSP). To determine the separate effects of these limitations on nutrient Digestibility, ground DDGS (383 μm) supplemented with phytase (0 or 250 units/kg of feed) and xylanase (0 or 4,000 units/kg of feed) was evaluated in a 2 x 2 factorial arrangement of treatments together with unground DDGS (517 μm) and an N-free diet in a 6 x 6 Latin square. Cofermented wheat and corn DDGS contained 8.6% moisture, 31.0% CP, 1.04% Lys, 8.0% ether extract, 2.0% starch, 40% NDF, and 0.85% P (as-is basis). Diets contained 43.7% DDGS as the sole source of AA; the digesta from pigs fed the N-free diet served to subtract basal endogenous AA losses and as control for energy Digestibility. Six ileal-cannulated barrows (37.1 ± 0.8 kg of BW) were fed 6 diets at 2.8 x maintenance for DE in six 9-d periods. Feces and ileal digesta were collected for 2 d each. The apparent ileal Digestibility (AID) of GE and apparent total tract Digestibility (ATTD) of GE and NDF were 2.3, 0.5, and 5.1%-units greater (P 0.05) the ATTD of crude fiber, ADF, P, and Ca in diets. Grinding of DDGS increased (P 0.05) to affect nutrient Digestibility. Phytase increased (P 0.05) AA Digestibility. Xylanase did not affect nutrient Digestibility. In conclusion, particle size is an important physical characteristic affecting Digestibility of energy and AA, but not P in DDGS. Phytate in DDGS limits Digestibility of P, but not energy and AA. The substrate for xylanase in DDGS did not hinder energy and AA Digestibility.
E N Fombang - One of the best experts on this subject based on the ideXlab platform.
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use of γ irradiation to alleviate the poor protein Digestibility of sorghum porridge
Food Chemistry, 2005Co-Authors: E N Fombang, John R N Taylor, Carl Moses Mbofung, Amanda MinnaarAbstract:One limitation to the use of sorghum as a food is that its proteins become more indigestible on wet-cooking, primarily through the formation of disulphide-linked enzymatically resistant protein polymers. Irradiation can modify bonds involved in protein secondary structure. The effects of irradiation (10 and 50 kGy) of dry and wet sorghum and maize flours on the Digestibility and solubility of their proteins, when further cooked into porridge, were investigated. Irradiation of sorghum flour, followed by cooking, alleviated the adverse effect of cooking on sorghum protein Digestibility. Maize porridge Digestibility was unaffected by irradiation of dry flour but decreased with wet-irradiation. Increase in Digestibility was not accompanied by an increase in protein solubility, suggesting that it was probably related to modification of protein structure, allowing better access to proteolytic enzymes. Maillard reactions and protein aggregation, at high doses, negatively affected Digestibility. Polyphenols influenced the effects of irradiation.
Abdullahi El H Tinay - One of the best experts on this subject based on the ideXlab platform.
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effect of cooking and treatment with sodium bisulphite or ascorbic acid on the in vitro protein Digestibility of two sorghum cultivars
Food Chemistry, 1997Co-Authors: Mawahib E Arbab, Abdullahi El H TinayAbstract:Two sorghum cultivars, Karamaka (high in tannin, 3.1%) and Gadam Elhamam (low in tannin, 0.35%), were used in this study. The effect of sodium bisulphite and ascorbic acid on in vitro protein Digestibility of the two sorghum cultivars was investigated. Varying concentrations of reducing agents, 0.05, 0.1, 0.25 and 0.5 M, and pepsin digestion times, 30, 60, 90, 120, 150 and 180 minutes, were considered. Reducing agents improved Digestibility for cooked and uncooked samples. 0.1 M concentration provided the highest level of Digestibility for both reducing agents. Cooking reduced in vitro protein Digestibility for both cultivars. Formation of disulphide bonds in cooked samples is probably responsible for the reduced protein Digestibility. Reducing agents prevent formation of disulphide bonds and improve the in vitro protein Digestibility. For all treatments, Karamaka holds a lower level of in vitro protein Digestibility than Gadam Elhamam cultivar. This could be attributed to the higher tannin content in Karamaka cultivar.