Effects of acute consumption of a beverage based on extruded whole-grain pearl millet flour on glycemic and insulinemic control, food intake, and appetite sensation in eutrophic adults: A randomized cross-over clinical trial.

OBJECTIVES: Whole-grain pearl millet is a nutritious cereal source of dietary fiber, vitamins, minerals, and bioactive compounds. It offers health benefits such as glycemic control and satiety. Extrusion cooking for diverse formulations, including beverages, can alter its chemical composition, impacting the nutritional value. This study aimed to evaluate the sensory acceptability of an extruded millet flour beverage and its acute effects on glycemic index (GI), glycemic and insulinemic response, food intake, and subjective appetite sensations in euglycemic and eutrophic adults. METHODS: This is an acute, single-blind, randomized, controlled, cross-over clinical study comprising 14 euglycemic and eutrophic adults. Initially, beverages based on whole extruded millet flour were developed, and sensorially and chemically analyzed. Next, a clinical trial was conducted with participants undergoing four sessions and consuming one of the following options: extruded millet beverage, a maltodextrin control beverage, or a glucose solution administered in two separate sessions. Blood glucose, insulin, and appetite responses were assessed over a 2-h period, in addition to determining the GI of the beverages and analyzing food intake in the 24 h following each session. RESULTS: The extruded millet flour strawberry-flavored beverage had the best sensory acceptance and was classified as having as high GI. Consumption of the extruded millet beverage showed similar glycemic and insulinemic responses, as well as appetite control and food intake of the subjects, when compared with consumption of the maltodextrin control beverage. CONCLUSIONS: Intake of the extruded millet beverage maintained glycemic and insulinemic responses, appetite control, and food intake in euglycemic and eutrophic subjects.

Loss-of-function of triacylglycerol lipases are associated with low flour rancidity in pearl millet [Pennisetum glaucum (L.) R. Br.].

Pearl millet is an important cereal crop of semi-arid regions since it is highly nutritious and climate resilient. However, pearl millet is underutilized commercially due to the rapid onset of hydrolytic rancidity of seed lipids post-milling. We investigated the underlying biochemical and molecular mechanisms of rancidity development in the flour from contrasting inbred lines under accelerated aging conditions. The breakdown of storage lipids (triacylglycerols; TAG) was accompanied by free fatty acid accumulation over the time course for all lines. The high rancidity lines had the highest amount of FFA by day 21, suggesting that TAG lipases may be the cause of rancidity. Additionally, the high rancidity lines manifested substantial amounts of volatile aldehyde compounds, which are characteristic products of lipid oxidation. Lipases with expression in seed post-milling were sequenced from low and high rancidity lines. Polymorphisms were identified in two TAG lipase genes (PgTAGLip1 and PgTAGLip2) from the low rancidity line. Expression in a yeast model system confirmed these mutants were non-functional. We provide a direct mechanism to alleviate rancidity in pearl millet flour by identifying mutations in key TAG lipase genes that are associated with low rancidity. These genetic variations can be exploited through molecular breeding or precision genome technologies to develop elite pearl millet cultivars with improved flour shelf life.

Transcriptome Analysis of Pennisetum glaucum (L.) R. Br. Provides Insight Into Heat Stress Responses.

Pennisetum glaucum (L.) R. Br., being widely grown in dry and hot weather, frequently encounters heat stress at various stages of growth. The crop, due to its inherent capacity, efficiently overcomes such stress during vegetative stages. However, the same is not always the case with the terminal (flowering through grain filling) stages of growth, where recovery from stress is more challenging. However, certain pearl millet genotypes such as 841-B are known to overcome heat stress even at the terminal growth stages. Therefore, we performed RNA sequencing of two contrasting genotypes of pearl millet (841-B and PPMI-69) subjected to heat stress (42°C for 6 h) at flowering stages. Over 274 million high quality reads with an average length of 150 nt were generated, which were assembled into 47,310 unigenes having an average length of 1,254 nucleotides, N50 length of 1853 nucleotides, and GC content of 53.11%. Blastx resulted in the annotation of 35,628 unigenes, and functional classification showed 15,950 unigenes designated to 51 Gene Ontology terms. A total of 13,786 unigenes were allocated to 23 Clusters of Orthologous Groups, and 4,255 unigenes were distributed to 132 functional Kyoto Encyclopedia of Genes and Genomes database pathways. A total of 12,976 simple sequence repeats and 305,759 SNPs were identified in the transcriptome data. Out of 2,301 differentially expressed genes, 10 potential candidate genes were selected based on log2 fold change and adjusted p value parameters for their differential gene expression by qRT-PCR. We were able to identify differentially expressed genes unique to either of the two genotypes, and also, some DEGs common to both the genotypes were enriched. The differential expression patterns suggested that 841-B 6 h has better ability to maintain homeostasis during heat stress as compared to PPMI-69 6 h. The sequencing data generated in this study, like the SSRs and SNPs, shall serve as an important resource for the development of genetic markers, and the differentially expressed heat responsive genes shall be used for the development of transgenic crops.

Addressing Iron and Zinc Micronutrient Malnutrition Through Nutrigenomics in Pearl Millet: Advances and Prospects.

Iron (Fe) and zinc (Zn) micronutrient deficiencies are significant health concerns, particularly among the underprivileged and resource-poor people in the semi-arid tropics globally. Pearl millet is regarded as a climate-smart crop with low water and energy footprints. It thrives well under adverse agro-ecologies such as high temperatures and limited rainfall. Pearl millet is regarded as a nutri-cereal owing to health-promoting traits such as high grain Fe and Zn content, metabolizable energy, high antioxidant and polyphenols, high proportion of slowly digestible starches, dietary fibers, and favorable essential amino acid profile compared to many cereals. Higher genetic variability for grain Fe and Zn content has facilitated considerable progress in mapping and mining QTLs, alleles and genes underlying micronutrient metabolism. This has been made possible by developing efficient genetic and genomic resources in pearl millet over the last decade. These include genetic stocks such as bi-parental RIL mapping populations, association mapping panels, chromosome segment substitution lines (CSSLs) and TILLING populations. On the genomics side, considerable progress has been made in generating genomic markers, such as SSR marker repository development. This was followed by the development of a next-generation sequencing-based genome-wide SNP repository. The circa 1,000 genomes re-sequencing project played a significant role. A high-quality reference genome was made available by re-sequencing of world diversity panel, mapping population parents and hybrid parental lines. This mini-review attempts to provide information on the current developments on mapping Fe and Zn content in pearl millet and future outlook.

Identifying Anti-Oxidant Biosynthesis Genes in Pearl Millet [Pennisetum glaucum (L.) R. Br.] Using Genome-Wide Association Analysis.

Pearl millet [Pennisetum glaucum (L.) R Br.] is an important staple food crop in the semi-arid tropics of Asia and Africa. It is a cereal grain that has the prospect to be used as a substitute for wheat flour for celiac patients. It is an important antioxidant food resource present with a wide range of phenolic compounds that are good sources of natural antioxidants. The present study aimed to identify the total antioxidant content of pearl millet flour and apply it to evaluate the antioxidant activity of its 222 genotypes drawn randomly from the pearl millet inbred germplasm association panel (PMiGAP), a world diversity panel of this crop. The total phenolic content (TPC) significantly correlated with DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity (% inhibition), which ranged from 2.32 to 112.45% and ferric-reducing antioxidant power (FRAP) activity ranging from 21.68 to 179.66 (mg ascorbic acid eq./100 g). Genome-wide association studies (GWAS) were conducted using 222 diverse accessions and 67 K SNPs distributed across all the seven pearl millet chromosomes. Approximately, 218 SNPs were found to be strongly associated with DPPH and FRAP activity at high confidence [-log (p) > 3.0-7.4]. Furthermore, flanking regions of significantly associated SNPs were explored for candidate gene harvesting. This identified 18 candidate genes related to antioxidant pathway genes (flavanone 7-O-beta-glycosyltransferase, GDSL esterase/lipase, glutathione S-transferase) residing within or near the association signal that can be selected for further functional characterization. Patterns of genetic variability and the associated genes reported in this study are useful findings, which would need further validation before their utilization in molecular breeding for high antioxidant-containing pearl millet cultivars.

Potential use of king grass (Pennisetum purpureum Schumach. × Pennisetum glaucum (L.) R.Br.) for phytoextraction of cadmium from fields.

Using king grass (Pennisetum purpureum Schumach. × Pennisetum glaucum (L.) R.Br.) for phytoextraction is a promising technology for producing large amounts of biomass fuel while remediating contaminated soil. To assess the practical phytoextraction capacity of king grass, we conducted a field experiment with three different soil types (loam, sandy loam, clay loam) and cadmium (Cd) concentrations (0, 0.25, 0.5, 1, 2, 4, 8, and 16 mg kg-1, aged stably for 6 years). King grass were harvested at two different periods (elongation and maturity) to identify the optimal harvest time for extraction efficiency. The results showed that all treatments had bioconcentration factor (BCF) > 1 and translocation factor (TF) < 1; Cd is mainly stored in the roots. However, due to a high shoot biomass, the highest quantity of Cd extracted from shoots was 2.75 mg plant-1, from the experimental group with 16 mg kg-1 Cd added in sandy loam. A significant positive relationship (P < 0.05) was observed between the amount of Cd extracted from king grass stems, leaves, and roots from soil with the diethylene triamine pentacetate acid (DTPA) extractable Cd concentration. The Cd concentration in shoots at the maturity stage is lower than at the elongation stage, mainly due to the effect of biological dilution. Meanwhile, there is significantly more biomass (P < 0.05) at the maturity stage than at the elongation stage. At the latter, the extraction efficiency of the three soils was loam > sandy loam > clay loam, while at maturity it was sandy loam > clay loam > loam. This change in extraction efficiency can be attributed mainly to differences in soil DTPA-extractable Cd concentration and growth rate caused by differences in soil physical and chemical properties. According to calculations from multiple harvests using three types of soil, remediating contaminated soil with 0-16 mg kg-1 Cd would take 13.9-224.5 and 19.5-250.6 years, extracting 7.21-265.23 and 4.96-330.52 g ha-1 Cd while producing 33.62-66.50 and 73.8-110.5 t ha-1 dry biomass at the elongation (90 days) and maturity (120 days) stages, respectively. In summary, king grass has major potential for remediating Cd-contaminated soil while producing large volumes of biofuel.

Production and quality of silages pearl millet and paiaguas palisadegrass in monocropping and intercropping in different forage systems / Produção e qualidade da silagem de milheto e capim-paiaguás em monocultuvo e consorciado em diferentes sistemas forrageiros

With the arrival of new early genotypes and high nutritive value and productive potential, millet has been gaining prominence in recent years for the production of silage, and it promises lower costs of production. Thus, the consortium of millet with tropical forages can increase the production of silage, providing more food to be used in the offseason, where there is low availability of forage. The objective of this study was to evaluate the dry mass production, fermentative characteristics and chemical-bromatological of pearl millet silage and Paiaguas palisadegrass in monocropping and intercropping in different forage systems in the second cropping season. The experimental design consisted of randomized blocks with four replicates. The treatments consisted of silage of the following forage systems: monocropped pearl millet, monocropped Paiaguas palisadegrass, pearl millet intercropped in rows with Paiaguas palisadegrass, pearl millet intercropped inter-row with Paiaguas palisadegrass, and pearl millet oversown and intercropped with Paiaguas palisadegrass (totaling 20 experimental plots). The consortium of pearl millet with Paiaguas palisadegrass contributed to raise the dry matter contents of the silages, except in the system using the overgrowth. Pearl millet silages monocropped and intercropped with Paiaguas palisadegrass presented reductions in pH and ammoniacal nitrogen values as well as favor lactic fermentation. Pearl millet monocropped and intercropped silage exhibited better fermentative and bromatological characteristics than silage obtained from monocropped Paiaguas palisadegrass. Therefore, creating silage from intercropped forages provides an interesting supplemental roughage option that can be used during the offseason for animal feeding.

Com a chegada de novos genótipos precoces e de alto valor nutritivo e potencial produtivo, o milheto vem ganhando destaque nos últimos anos para a produção de silagens, com menor custo de produção. Com isso, o consórcio do milheto com forrageiras tropicais, pode aumentar a produção da silagem, proporcionando maior quantidade de alimento para ser utilizado na entressafra, onde se tem baixa disponibilidade de forragem. Sendo assim, objetivou-se avaliar a produção de massa seca, características fermentativas e a composição químico-bromatológica da silagem de milheto e capim-paiaguás em monocultivo e consorciado em diferentes sistemas forrageiros, na safrinha. O delineamento experimental utilizado foi em blocos casualizados, com quatro repetições. Os tratamentos foram constituídos da silagem dos seguintes sistemas forrageiros: milheto em monocultivo, capim-paiaguás em monocultivo, milheto consorciado com capim-paiaguás na linha, milheto consorciado com capim-paiaguás na entrelinha e milheto consorciado com capimpaiaguás na sobressemeadura, totalizando 20 silos experimentais. O consórcio do milheto com capim-paiaguás contribuiu para elevar os teores de matéria seca das silagens, exceto, no sistema utilizando a sobressemeadura. As silagens de milheto em monocultivo e consorciadas com capim-paiaguás apresentaram reduções nos valores de pH e nitrogênio amoniacal, bem como, favorecem a fermentação lática. As silagens de milheto em monocultivo e consorciadas apresentaram melhores características fermentativas e bromatológicas quando comparadas com silagem de capim-paiaguás em monocultivo. Portanto, silagens produzidas nos sistemas consorciados constitui interessante opção de volumosos suplementar para alimentação dos animais no período de entressafra.

Production and bromatological composition of pearl millet genotypes for pasture manned in different cutting heights / Produção e composição bromatológica de genótipos de milheto para pastejo manejados em diferentes alturas de corte

Desenvolveu-se esse estudo com o objetivo de avaliar a produção e a composição bromatológica de genótipos de milheto, manejados em diferentes alturas e submetidos a vários cortes. O delineamento experimental utilizado foi o de blocos completos ao acaso, com medidas repetidas no tempo, com quatro repetições, em esquema fatorial 3 x 3, sendo três cultivares de milheto (ADR 500, LAB 1542 e LAB 1838) e três alturas média de cortes (60; 80 e 100 cm). As avaliações foram realizadas durante quatro meses, consistindo de avaliações por cortes nas mesmas parcelas. Os resultados demonstraram que os genótipos de milheto representam uma boa alternativa para pastejo. Os genótipos (ADR 500; LAB 1542 e LAB 1838), apresentaram produção de massa seca e composição bromatológica semelhantes entre os materiais. A qualidade da forragem é afetada pelo manejo da altura de corte, sendo assim recomenda-se que os genótipos de milheto sejam manejados nas alturas de 80 cm, para associar melhor produção e qualidade da forragem.

Plantas de cobertura no controle da erosão hídrica sob chuvas naturais / Cover plants in water erosion control under natural rainfall

As plantas de cobertura desempenham um conjunto de ações integradas que proporcionam benefícios aos sistemas agrícolas, com destaque para a redução da erosão hídrica que é a principal forma de degradação dos solos brasileiros. Assim, objetivou-se com este trabalho quantificar as perdas de solo, água e o potencial de arraste de sedimentos decorrentes da erosão hídrica, sob chuva natural. Neste experimento foram utilizadas quatro espécies de plantas de cobertura em dois sistemas: consórcio milheto (Pennisetum glaucum (L.) R.Brown) com crotalária (Crotalaria spectabilis Roth) e consórcio de milheto com feijão-guandu (Cajanus cajan (L.) Huth), além do cultivo solteiro do milheto, feijão-guandu, feijão-de-porco (Canavalia ensiformis (L.) DC) e crotalária. Para a quantificação das perdas de solo, água e potencial de arraste de sedimentos do solo utilizaram-se parcelas de 4 x 12 m. Observou-se que os maiores índices de cobertura foram obtidos pelas espécies feijão-de-porco (77,63%), feijão-guandu (64,55%) e pelo consórcio milheto + feijão-guandu (64,11%). As menores perdas de solo foram obtidas pelo cultivo do feijão-guandu (1,27 Mg ha-1), do milheto (1,47 Mg ha-1) e do feijão-de-porco (1,77 Mg ha-1), e as menores perdas de água foram obtidas pelo cultivo do feijão-guandu (37,90 mm), do consórcio milheto + crotalária (40,04 mm) e pelo feijão-de-porco (41,83 mm). Não é possível inferir sobre uma relação entre os índices fitotécnicos e a proteção do solo contra a erosão hídrica.

Cover crops play a set of integrated actions that provide benefits to agricultural systems, with emphasis on reducing water erosion that is the main form of land degradation in Brazil. Thus the aim of this work was to quantify the losses of soil, water and the potential for entrainment of sediment resulting from water erosion under natural rainfall. In this experiment we used four species of cover crops in two systems: intercropping sunn hemp with millet and intercropping millet with pigeon pea, and the cropping to millet, pigeon pea, jack bean and sunn hemp. To quantify the losses of soil, water and the potential for entrainment of soil sediment were used plots of 4 x 12 m. It was observed that the highest rates of coverage were obtained by species jack bean (77.63%), pigeon pea (64.55%) and the consortium millet + pigeon pea (64.11%). The lowest soil loss was obtained by cultivation of pigeon pea (1.27 Mg ha-1), millet (1.47 Mg ha-1) and jack bean (1.77 Mg ha-1), and lowest water loss was obtained by cultivation of pigeon pea (37.90 mm), in the consortium millet + sunn hemp (40.04 mm) and jack bean (41.83 mm). It is not possible to infer a relationship between the rates phytotechnical and protection against soil erosion.

In vitro morphogenesis of pearl millet [Pennisetum glaucum (L.) R.Br.]: efficient production of multiple shoots and inflorescences from shoot apices.

This report presents a procedure for high-frequency multiple shoot production from cultured shoot apical meristems of pearl millet [Pennisetum glaucum (L.) R. Br.]. Shoot apices from 1-week-old aseptically germinated seedlings were cultured in vitro on MS medium containing various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and benzyladenine (BA) with biweekly subculture. A low concentration of 2,4-D coupled with four different concentrations of BA induced the production of adventitious shoots from the enlarged shoot apical meristems. Somatic embryogenesis was also observed at higher concentrations of BA. The use of higher levels of 2,4-D resulted in callusing of shoot apical meristems, while the shoot tips produced many leaves and in vitro flowering in 2,4-D-free media containing BA. All four pearl millet genotypes produced similar results. Fertile pearl millet plants were produced from in vitro-produced multiple shoots.