Isolation and characterization of a 20 kD prolamin from kodo millet (Paspalum scrobiculatum) (L.): Homology with other millets and cereals

The homologus 20 kD prolamin from kodo millet and other minor millets viz. barnyard, little and foxtail millets, were purified using preparative gel electrophoresis and reversed phase high performance liquid chromatography (RP-HPLC). The amino acid composition of the purified 20 kD prolamin protein from different minor millets revealed higher content of glutamic acid, alanine, leucine and serine and lower quantity of lysine and methionine. They contain 55 to 58 percent of non-polar amino acids which make them more hydrophobic than other protein fractions. The total number of amino acid residues per polypeptide chain ranged from 152 to 155 based on theoretical calculation. Peptide mapping of the 20 kD prolamin hydrolyzed with trypsin gave fewer cleavage products than expected. The antigenic relationships among these minor millets and cereals viz. wheat, maize, rice, sorghum, finger millet and pearl millet were studied using the antibody raised against the 20 kD prolamin. Cross reactivity was seen in all the minor millets at the 20 kD region. But in barnyard and little millets lower molecular weight polypeptides also cross reacted with the antibody. Immunoblotting studies revealed that the prolamins from other cereals and millets are related to the 20 kD prolamin of kodo millet. Rice was the only common cereal that did not cross react immunologically with the antibody raised against 20 kD prolamin of kodo millet.     

Nutrient composition and protein quality of minor millets

Nutrient composition of five minor millets produced and consumed in dry land regions and tribal areas of Andhra Pradesh, India, was evaluated. The millets analysed were Italian millet (Setaria Italica), French millet (Panicum miliaceum), Barnyard millet (Echinachloa colona), Kodo millet (Paspalum scrobiculatum) and little millet (Panicum miliare). The nutrients analysed were proximate principles, amino acids, fibre components, calcium, Phosphorus and Iron. Protein and energy were evaluated by true digestability (TD), biological value (BV), net protein utilization (NPU) and digestible energy (DE) in rats. The protein content was higher and lysine content lower, when compared to major millets. Dehusked millets had lower total dietary fibre (TDF) and tannin. The TD of protein ranged between 95.0 to 99.3, whereas the BV was between 48.3 and 56.5. All the millets were poor sources of calcium, phosphorus and iron, with the exception of french millet.     

Effect of heating and fortification with lysine on protein quality of minor millets

The effect of heating and fortification with lysine on the protein quality of five minor millets namely Italian millet (S. Italica), French millet (Panicum miliaceum), Barnyard millet (Echinochloa colona), Kodo millet (Paspalum scrobiculatum) and Little millet (Panicum miliare) was carried out. The N content of the millets ranged from 1.69 to 2.76 per cent. Proximate composition and dietary fibre was estimated. A reduction of 19–25 in TD and increase of 4–18 in BV was observed on auto-claving and both the differences were significant (P<0.05) in all millets. However, heat processing did not have a pronounced effect on DE. Fortification with lysine at 0.6 g/100 DM increased both the BV and NPU. Although both heat processing and lysine fortification improved protein utilisation, the effect of fortification was comparatively more than heating.     

Homologies between prolamins of different minor millets

Minor millets, viz. Barnyard millet, Proso millet, Little millet, Foxtail millet and Kodo millet, one variety in each grown in Tamil Nadu Agricultural University (TNAU), Coimbatore, Tamil Nadu were selected for the study. The protein contents of the selected decorticated millets were found to be 11.0, 12.3, 12.9, 10.5 and 10.6% respectively. Fractionation of these proteins revealed that prolamin forms major storage protein in Foxtail millet whereas, glutelin forms major storage protein in all the other millets. The extractability was studied using different solvents, viz. isopropyl alcohol, t-butyl alcohol and ethyl alcohol with varying concentration of 2-mercapto ethanol. Electrophoretic pattern of the extracted prolamins from these millets were compared and found that a protein band at the molecular weight range of 20 kD was found homologous in all except Proso millet. The extractability of the 20kD protein in 90% isopropyl alcohol showed its strong hydrophobic nature.     

Nutritional evaluation of chickpea and germinated chickpea flours

The ability of seed germination to increase the nutritional quality of chickpea was studied. Chickpea flours germinated for 0, 24 and 48 h were evaluated nutritionally by determination of protein efficiency ratio (PER), net protein ratio (NPR), digestibility and essential amino acid availability in vivo. A significant increase in ascorbic acid was observed during germination. PER and NPR values indicated that germinated chickpea flours compared favorably to casein. Protein digestibility decreased as germination time increased. Essential amino acid availability did not change after 24 h of germination, but a small decrease was observed after 48 h. The increase in some amino acids during germination may account for the observed increase in PER for the germinated flours. Seed germination enhanced significantly the nutritional quality of chickpea protein and substantially increased the ascorbic acid level.Contribution No. 4359, Arizona Agricultural Experiment Station, University of Arizona, Tucson, AZ 85721, USA.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

大麦芽的主要成分及其在食品工业中的应用

大麦在发芽过程中能激活自身的合成和代谢系统,产生或激活一些酶,可以降低某些抗营养物质的含量,提高蛋白质和淀粉的可消化吸收率及必需氨基酸等物质的含量,故大麦芽具有很高的营养价值。本文综述了大麦芽的主要营养物质及其在食品加工中的应用和研究现状,以期为未来大麦芽产品的加工和应用提供借鉴和帮助。     

Characterization of starches of proso,foxtail, barnyard,kodo, and little millets

Scanning electron microscope (SEM) pictures of small millet starch granules showed more large polygonal and few small spherical or polygonal granules. The granules of small millets resembled those of rice starch granules. The size of the starch granules ranged from 0.8–10 m. The size of the granules was larger in barnyard millet and smaller in proso millet. Several granules showed deep indentation caused by protein bodies. SEM of starch isolated from 24 hour-germinated kodo millet showed pitting or pinholes at some points due to the attack of amylases (preferentially on bigger granules). Brabender viscoamylograph studies on small millet starches revealed that the gelatinization temperatures ranged from 75.8 to 84.9 ^° C. Barnyard millet possessed lower amylograph viscosity, minimum breakdown, and relative breakdown values when compared to the other small millets.     

Changes in the carbohydrates and nitrogenous components during germination of proso millet,Panicum miliaceum

Since germination has been found to increase the nutritive qualities of grains, proso millet, a minor millet, was allowed to germinate for 1–7 days and analysed for protein fractions, free amino acids, lysine, tryptophan, methionine, non-protein nitrogen, starch, and sugars. Overnight soaking and germination up to 7 days significantly increased the free amino acids and total sugars while the content of dry weight and starch decreased. Increases in albumin and globulin and large decreases in prolamin accompanied sprouting. The percent protein in germinated grains was higher than in the initial grain as a result of dry matter loss during germination. Further, there was an increase in lysine, tryptophan and non-protein nitrogen contents during germination. No change was noticed in methionine content.     

Tolerance of foxtail,proso and pearl millets to saflufenacil

Herbicide options for weed control in millets are very limited and hence there is a need for exploring potential herbicides. Field trials were conducted at three locations in Kansas and Nebraska in 2009 to evaluate foxtail millet, proso millet, and pearl millet tolerance to saflufenacil applied preemergence (PRE) at 36, 50, and 100 g ai ha⁻¹. Foxtail millet was the most sensitive of the three millets to saflufenacil. Among experimental sites, saflufenacil at 36 g ha⁻¹ injured foxtail millet 59–99% and reduced plant stands 41–95%; nearly all plants died at 100 g ha⁻¹. Despite early season foliar injury and up to 36% stand reduction, fodder or grain yields of proso and pearl millets were not reduced by any rate of saflufenacil compared to untreated controls. Additional trials were conducted at four locations in Kansas, Nebraska and South Dakota in 2010 and 2011 to refine saflufenacil use rate (36 and 50 g ha⁻¹) and application timing [14 days early preplant (EPP); 7 days preplant (PP); and PRE] for use in proso and pearl millets. Saflufenacil applied EPP or PP, regardless of rate, caused up to 21 and 6% foliar injury and up to 21 and 9% plant stand reduction in proso and pearl millets, respectively. However, yields were not reduced by EPP or PP treatments in either millet crop. PRE applications of saflufenacil caused the highest crop injury and stand reduction in both millets. Saflufenacil PRE at 36 g ha⁻¹ caused up to 57 and 40% foliar injury and up to 42 and 24% stand reductions in proso and pearl millets, respectively; however, yields were not affected. Comparatively, saflufenacil PRE at 50 g ha⁻¹ reduced yields of proso and pearl millets 36 and 52%, respectively, on sandy loam soils with high pH (8.3) and low organic matter content (1.1%). Overall, results indicated that foxtail millet lacks tolerance to saflufenacil, but up to 50 g ha⁻¹ of saflufenacil may be safely applied as near as 7 days before planting proso or pearl millets. If situation demands, saflufenacil at 36 g ha⁻¹ can also be applied PRE to either crop with risk of some crop injury.     

大麦籽粒中γ 氨基丁酸、总黄酮和生物碱含量在发芽过程中的变化

为了解大麦发芽过程中功能成分的变化,用分光光度计测定了28份大麦籽粒发芽前(无菌水浸泡24h,记作发芽0d)及发芽1～9d的γ-氨基丁酸(GABA)、总黄酮和生物碱的含量差异,结果表明:(1)大麦籽粒中的GABA和生物碱含量均为发芽0d高于发芽1～2d,而明显低于发芽3～9d的相应含量;发芽前后GABA累积最大均值是最小均值的2.1倍,生物碱累积最大均值是最小均值的11.6倍。(2)大麦籽粒发芽前总黄酮含量最高,发芽后相对较低;而发芽4～8d期间的GABA和生物碱含量相对较高。(3)不同大麦品系间籽粒GABA和生物碱含量在发芽4～6d差异明显,且达到峰值的频率较高;籽粒总黄酮含量在发芽8～9d差异明显,发芽前总黄酮含量达到峰值的频率最高。     

Effect of processing on protein digestibility,biological value and net protein utilization of millet and legume based infant mixes and biscuits

Effect of combinations of millet and legume and processing on digestibility, biological value and net protein utilization was evaluated using albino rats. The millets and legumes selected for the study include sorghum, pearl millet, finger millet, chickpea and green gram (P radiatus). The processes tested include dehulling, boiling, roasting, malting and baking. Among the combinations tested, the sorghum-chickpea combination had significantly (p<0.05) higher digestibility. Between the processes tested, roasting resulted in significantly higher net protein utilization. Results of biological study on biscuits prepared by using millet and legume combination flours, indicated the biscuits to be of good protein quality.     

Influence of germination time and temperature on the properties of rye malt and rye malt based worts

The effects of germination time and temperature on the quality of rye malt and worts derived thereof were investigated using Response Surface Methodology. Amylolytic and proteolytic enzyme activities were increased by long germination periods, while β-glucanase activity was not influenced. Total and Soluble Nitrogen content were also not significantly affected by the variations in germination conditions. Free Amino Nitrogen (FAN) was found in higher amounts in worts prepared from rye malts with long germination times. Extract contents were higher in rye malt than in the control barley malt and could be increased by a favourable germination regime, while no such impact on wort fermentability was found. High wort viscosities could be significantly reduced by a long germination period at low temperatures, but were still unacceptably high. The same conditions favoured the development of endoxylanase activity. Arabinoxylan (AX) accumulated during the germination process and their extractability increased. The results suggest that longer germination periods resulted in an increased number of AX molecules with lower molecular mass. Optimal rye malt qualities within the limits of this study were found for a germination time of 144 h at 10 °C, which resulted in an acceptable FAN content and the lowest measured viscosity.     

Reduction of polyphenol and phytic acid content of pearl millet grains by malting and blanching.

This work was undertaken to evaluate the changes in polyphenol and phytic acid content in malted and blanched pearl millet grains. For malting, grains were steeped for 16 hours, germinated for 48 or 72 hours and then kilned at 50 degrees C for 24 hours. Blanching was done for 30 seconds in boiling water at 98 degrees C. Results indicated that blanching resulted in significant reduction in polyphenol (28%) and phytic acids (38%). Destruction of polyphenols (38 to 48%) and phytic acid (46 to 50%) was significantly higher in grains subjected to malting than blanching: The overall results suggested that malting with 72 hours of germination was most effective in reducing the antinutrient levels of pearl millet grains.     

Growth of Roots Emerged from Excised Phytomers of Three Gramineous Species under a Low Osmotic Potential

Abstract

The growth of crown and lateral roots emerged from the excised phytomers of pearl millet (Pennisetum typhoideum Rich.), barnyard millet (Echinochloa frumentacea Link.) and maize (Zea mays L.) was studied under normal and low osmotic potential conditions. The plants were grown in two solutions with osmotic potentials of –0.02 and –0.54 MPa for 6 days. The relative growth rate of the roots in total length (RGR_L) , was not affected by osmotic stress in pearl and barnyard millets, but that in stressed maize was reduced to 64% of the control. Similarly, the relative growth rate of the roots in dry weight (RGR_W), was not affected by osmotic stress in pearl and barnyard millets, but significantly reduced in maize. Osmotic stress increased the specific root length of the lateral roots in pearl and barnyard millets, but did not affect that of maize. The photosynthetic rate (Pr) in the two millets was decreased to ca. 60% of the control by the stress, and that in maize was reduced to 21%. Under the stress, Pr in the three species was limited mainly by low stomatal conductance, but no clear relationship was found between Pr and osmotic adjustment of the leaf. The relative water content of the leaf was lower in maize than in the two millets. The resistance to water flow through the phytomer (R) was significantly increased by osmotic stress in maize, but not significantly in the two millets. The mean root length (RL) was decreased by the stress in maize, but not in the two millets. The maintenance of RGR_L in the two millets was associated with sustained R, RL and also with the maintenance of Pr and allocation of assimilates to roots.     

Content and quality of protein in proso millet (Panicum miliaceum L.) varieties

Proso millet belongs to the oldest cereals that human is using. Eight varieties of proso millet were cultivated in Ceske Budejovice from 1998 to 2000 and Cerveny Dvur from 1999 to 2000. The crude protein content was determined according to Kjehladl method and amino acid content was determined chromatographically after acid and oxidative acid hydrolysis. Although the protein content of proso (11.6% of dry matter) was similar to wheat, the grain of proso was significant richer in essential amino acids (leucine, isoleucine, methionine) then wheat. Hence, the protein quality of proso (Essential Amino Acid Index) was higher (51%) compared to wheat. The proso grain contained about 3.3 g kg(-1) of the limiting amino acid-lysine. Significant differences in protein and its quality were found among the evaluated proso varieties. The varieties Toldanskoe and Lipetskoe were the most different from the others in protein and amino acid content and Amino Acid Score of individual acids. They had the lowest content and quality of protein. The seed coat of these varieties was red. The amino acid and protein content was significantly influenced by weather during the year. Dry conditions caused an increase of protein but its quality was decreased.     

Reduction of polyphenol and phytic acid content of pearl millet grains by malting and blanching

This work was undertaken to evaluate the changes in polyphenol and phytic acid content in malted and blanched pearl millet grains. For malting, grains were steeped for 16 hours, germinated for 48 or 72 hours and then kilned at 50 ^°C for 24 hours. Blanching was done for 30 seconds in boiling water at 98 ^°C. Results indicated that blanching resulted in significant reduction in polyphenol (28%) and phytic acids (38%). Destruction of polyphenols (38 to 48%) and phytic acid (46 to 50%) was significantly higher in grains subjected to malting than blanching. The overall results suggested that malting with 72 hours of germination was most effective in reducing the antinutrient levels of pearl millet grains.     

Content and Quality of Protein in Proso Millet (Panicum miliaceum L.) Varieties

Proso millet belongs to the oldest cereals that human is using. Eight varieties of proso millet were cultivated in Ceske Budejovice from1998 to 2000 and Cerveny Dvur from 1999 to 2000. The crude protein content was determined according to Kjehladl method and amino acid content was determined chromatographically after acid and oxidative acid hydrolysis. Although the protein content of proso (11.6% of dry matter) was similar to wheat, the grain of proso was significant richer in essential amino acids (leucine, isoleucine, methionine) then wheat. Hence, the protein quality of proso (Essential Amino Acid Index) was higher (51%) compared to wheat. The proso grain contained about 3.3 g kg⁻¹ of the limiting amino acid-lysine. Significant differences in protein and its quality were found among the evaluated proso varieties. The varieties Toldanskoe and Lipetskoe were the most different from the others in protein and amino acid content and Amino Acid Score of individual acids. They had the lowest content and quality of protein. The seed coat of these varieties was red. The amino acid and protein content was significantly influenced by weather during the year. Dry conditions caused an increase of protein but its quality was decreased.     

Ukrainian Dietary Bread with Selenium-Enriched Soya Malt

The production of bread with addition of selenium-enriched soya malt was studied. Processing of this soya malt included soaking of the soya beans in the solution of hydroselenite with concentration 1.5 mg Se/L (20 μg of Se per 1 g of soya beans), then 4 days of beans germination at 20 °C, drying at 50 °C until moisture content 8%, separation from the sprouts and grinding. The soya malt was a powder containing 15–18 μg of Se in 1 g. The accumulated selenium was mainly in the protein fraction of soya malt. Addition of selenium-enriched soya malt to leaven intensified activity of yeasts and lactic acid bacteria. The quality of the wheat bread with selenium-enriched soya malt was better than that of the bread in control. The enriched bread had specific pleasant smell and soft texture. The daily intake of 277 g of bread with the selenium-enriched soya malt, which is added in quantity of 1.0–1.75% to mass of plain flour, ensures the consumption of 30–50% of selenium recommended daily allowance for 17 million population of the northern and northwestern Ukraine.