Formulation and quality evaluation of finger millet (Eleusine coracana (L.) gaertn.) flour incorporated biscuits.

Replacing the ingredients used in biscuits with potential nutritive ingredients would be beneficial to improve the nutritional quality of the biscuits. Although, finger millet is highly nutritious when compared to other most commonly consumed cereals, limited availability of processed food products in ready-to-eat form has restricted the finger millet consumption. The present study was focused on formulating biscuits by replacing refined wheat flour with finger millet flour. Four biscuit samples were formulated by replacing different percentages of refined wheat flour with finger millet flour. Physicochemical and microbiological properties of the biscuits were evaluated. Nutritional and antioxidant properties of the biscuit, which was formulated by replacing 50% of refined wheat flour with finger millet flour, were evaluated and compared with a control biscuit which was prepared using refined wheat flour. The finger millet flour incorporated biscuit was nutritionally superior to the control biscuit in terms of dietary fibers and polyphenolic compounds including flavonoids. Besides, replacement of refined wheat flour with finger millet flour in biscuit formulation enhanced the antioxidant properties of the biscuit. Therefore, the finger millet flour incorporated biscuit can be considered as a good source of antioxidants.

Anti-inflammatory and Antioxidant Properties of Finger Millet (Eleusine coracana (L.) Gaertn.) Varieties Cultivated in Sri Lanka.

The prevalence of inflammatory-mediated and oxidative stress-associated diseases is increasing worldwide, creating an increasing demand for novel sources of anti-inflammatory agents and antioxidants. This study was focused on determining the in vitro arachidonate 5-lipoxygenase (A5-LOX), xanthine oxidase (XO), hyaluronidase and oxidative burst inhibitory activities, and antioxidant properties of Ravi, Rawana, and Oshadha finger millet varieties using ethanolic and methanolic extracts. Among all extracts, the methanolic extract of Oshadha exhibited the highest A5-LOX (IC50 value: 484.42 µg/ml) and XO (IC50 value: 764.34 µg/ml) inhibitory activities. All extracts showed less than 50% hyaluronidase inhibitory activity at 1 mg/ml concentration. Methanolic extracts showed moderate inhibitory potential on reactive oxygen species (ROS) generated from whole blood phagocytes, with IC50 values ranging between 26.9 and 27.7 µg/ml, when compared to ibuprofen (IC50 value: 11.18 µg/ml). All extracts showed potent inhibition of ROS produced from polymorphonuclear neutrophils isolated from human blood when compared to ibuprofen (IC50 value: 2.47 µg/ml) and IC50 values of methanolic and ethanolic extracts ranged from 0.29 to 0.47 µg/ml and 1.35 to 1.70 µg/ml, respectively. All extracts had significantly high amounts of phenolic compounds including flavonoids and the potential to scavenge 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid (ABTS) cation, 2,2-diphenyl-1-picryl-hydrazyl (DPPH), and oxygen radicals. Besides, they were able to reduce metal ions and chelate metal ions terminating radical generating reactions. This is the first report of A5-LOX, XO, hyaluronidase, and oxidative burst inhibitory properties of any extract of any finger millet variety cultivated in Sri Lanka. The findings revealed the potential of using these finger millet extracts as natural sources of anti-inflammatory drug candidates. Additionally, the findings indicated that Ravi, Rawana, and Oshadha varieties are good sources of antioxidants. Therefore, consumption of these finger millet varieties on a regular basis may play an important role in the prevention and dietary management of oxidative stress-associated diseases.

Ultrasound-assisted hydration of finger millet (Eleusine Coracana) and its effects on starch isolates and antinutrients.

Finger millet (Eleusine Coracana) is rich in nutrients and minerals. The iron and calcium contents are comparatively higher than other cereal crops. Finger millet also has some antinutrients such as tannins and phytates, that needs to be removed for maximum health benefits. Traditionally, these antinutrients are removed by the hydration process. The conventional hydration process is time cumbersome and often results in poor quality grains. Ultrasonication during hydration of finger millet could reduce the processing time and antinutrient content in finger millet. The ultrasound amplitude, treatment time, and grain to water ratio during hydration were optimized. An ultrasound amplitude of 66%, treatment time of 26 min, and a grain to water ratio of 1:3 resulted in best desirability parameters with a reduction in phytate and tannin contents of the finger millet by 66.98 and 62.83%, respectively. Ultrasonication during hydration increased the water binding capacity and solubility of the finger millet starch. XRD study of the starch isolates confirmed the increased crystallinity of the particles. FESEM of the starch isolates also confirmed that ultrasound-assisted hydration of finger millet resulted in the desired size reduction and homogeneous distribution of starch particles. The optimized ultrasound-assisted hydration could be adopted and scaled up for bulk processing of finger millets.

Assessment and evaluation of cellulase production using ragi (Eleusine coracana) husk as a substrate from thermo-acidophilic Aspergillus fumigatus JCM 10253.

The cellulase production by filamentous fungi Aspergillus fumigatus JCM 10253 was carried out using agro-industrial waste ragi husk as a substrate in the microbial fermentation. The effect of the process parameters such as temperature, substrate concentration, pH, and incubation process time and their interdependence was studied using response surface methodology. The optimum cellulase activities were obtained at 50 °C under the conditions with 1-2% of substrate concentration at pH 2-4 for the incubation period of 7-8 days. The maximum carboxymethyl cellulase (CMCase) and ß-glucosidase activities with optimized process variables were 95.2 IU/mL and 0.174 IU/mL, respectively. The morphological characterization of fungus by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) revealed the presence of secondary protein structures. Furthermore, this study demonstrated that the application of ragi husk could be a promising feedstock for value-added industrial products. The thermo-acidophilic nature of isolated strain Aspergillus fumigatus JCM 10253 possessed a significant potential for higher titer of cellulase production that could be further employed for lignocellulosic bioethanol production.

Nutritional and phytochemical profiling of nutracereal finger millet (Eleusine coracana L.) genotypes.

Finger millet (Eleusine coracana L.) is gaining popularity as healthy food due to its nutritional and phytochemical properties. This study reports nutritional and phytochemical profile of ten finger millet genotypes. Proximate analysis of finger millet genotypes revealed moisture, total carbohydrate, protein, fat, fiber and ash in the range of 7.50-11.75, 71.90-76.38, 6.7-8.0, 1.2-1.7, 3.1-3.8 and 3.1-3.8 per cent respectively. Micro-nutrient profiling showed Ca, Fe, Zn, P, K and Mn in the range of 2400.00-3400.00, 40.28-47.60, 12.40-17.45, 1600.00-2900.00, 3800.00-5200.00 and 51.33-61.28 mg kg-1 respectively. Phytochemical profiling was done for total phenol, phytic acid, tannins, flavonoids, HCN, oxalate and trypsin inhibitor which were observed in the range of 99.75-112.25, 210.75-302.75, 340.00-500.00, 62.23-74.05, 2.45-2.80, 19.80-26.23 mg 100 g-1 and 207.35-234.23 TIU g-1 respectively. Amino acid profiling showed good amount of essential amino acids. Nutritional and phytochemical profiling of finger millet genotypes showed its potentiality to become source of health promoting food.

Isolation of ß-glucan from Eleusine coracana and its antibiofilm, antidiabetic, antioxidant, and biocompatible activities.

Eleusine coracana (Finger millet) has high nutritional value with numerous health benefits and is of low cost. Isolation of beta-glucan (ßG) from E. coracana (Ec-ßG) has gained increasing research attention. UV-vis spectroscopy used to measure the surface plasmon resonance at 361 nm to confirm the presence of polysaccharides (glucan molecules) in Ec-ßG. X-ray diffraction analysis of Ec-ßG displayed a crystalline nature and confirmed the presence of the ßG molecule. Further, the bioactive compounds of Ec-ßG were screened using gas chromatography-mass spectrometry. The antibacterial activity of Ec-ßG against both Gram-positive (Lysinibacillus fusiformis, Enterococcus faecalis) and Gram-negative (Proteus vulgaris, Shigella sonnei) bacteria were assessed through minimum inhibitory concentrations <70 µg/ml of Ec-ßG. In addition, the antibiofilm activity and bacterial viability of Ec-ßG at 100 µg/ml was confirmed by light and confocal laser scanning microscopy. Furthermore, Ec-ßG inhibits α-amylase and α-glucosidase at an IC50 -value of 1.23 and 1.42 µg/ml, respectively. Superoxide anion scavenging activity at IC50-1.4 µg/ml and DPPH radical scavenging activity at IC50-1.2 µg/ml showed that Ec-ßG had potential antioxidant property. The in vitro hemolysis assay for biocompatibility of Ec-ßG at 200 µg/ml showed 0.06 ± 0.09%. Therefore, Ec-ßG has the potential to act as a suggestive agent for antibacterial, antidiabetic, and antioxidant activity.

Polyhydroxyalkanoate (PHA) biosynthesis from directly valorized ragi husk and sesame oil cake by Bacillus megaterium strain Ti3: Statistical optimization and characterization.

Polyhydroxyalkanoates (PHAs) signify the most promising biological substitute to petrochemical plastics. Renewable and inexpensive agro-industrial by-products can be used as potent fermentation feedstocks for sustainable PHA biosynthesis. This study aimed at using a wild type B. megaterium strain Ti3 innate hydrolytic enzyme/s for eco-friendly valorization of 16 lignocellulosic agrowastes to PHA without pretreatments. Initial hydrolytic screening PHA concentration of (0.04-0.17 g/L), highlighted the strain's metabolic versatility. Pareto ranking of Taguchi orthogonal array (TOA) established ragi husk (RH), sesame oil cake (SOC) and KH2PO4 as the most influential factors (p < 0.05). The optimized and validated Response surface methodology (RSM) model (R2, 0.979; desirability, 1) resulted in 3.8 and 3.6 fold increased PHA production, 4.3 and 3.25 fold increased PHA productivity. A positive correlation (r2, 0.5-0.97) was observed amid the producer innate hydrolytic enzymes (lipase, amylase and cellulase) and PHA production. The PHA was characterized by 1H and 13C NMR, GPC, TGA. The polymer was identified as a scl-mcl copolyester with 92% 3HB (3-hydroxybutyrate) and 8% 3HHp (3-hydroxyheptanoate) monomers by NMR. This the first report on B. megaterium self-enzyme reliant non-food agrowastes bioconversion to PHA with 3HHp (3-hydroxyheptanoate) monomers excluding precursor addition, commercial enzymes, pure carbon and nitrogen sources.

Comparative evaluation of effective microbe- and urea molasses-treated finger millet (Eleusine coracana) straw on nutritive values and growth performance of Washera sheep in northwestern Ethiopia.

An experiment was carried out to comparatively evaluate the effect of effective microbe (EM)- and urea molasses (UM)-treated finger millet straw (EMTFMS and UMTFMS, respectively) on nutrient utilization and growth performance of Washera lambs. Twenty yearling intact male Washera lambs with an initial body weight of 21.13 ± 1.77 kg (mean ± SE) were used for feeding and digestibility trial. These lambs were grouped into five blocks of four animals and randomly assigned to four dietary treatments. The four experimental feeds were untreated finger millet straw (control) + 150 g wheat bran (WB) (T1), untreated finger millet straw + 150 g WB + 150 g Noug seed cake (NSC) (T2), UMTFMS + 150 g WB + 150 g NSC (T3), and EMTFMS + 150 g WB + 150 g NSC (T4). The lambs were de-wormed and vaccinated against ecto- and endo-parasites. Data were analyzed using ANOVA procedure of SAS. Results showed that crude protein (CP) content of finger millet straw (FMS) was improved from 2.13 to 9.7% in UM treatment and 2.13 to 2.39% in EM treatments. Total DM, CP, and OM intake were higher in lambs assigned in UMTFMS (P < 0.01) and EMTFMS (P < 0.01) than the control groups and significantly highest (P < 0.01) in UMTFMS. A non-significant (P > 0.05) difference was observed between treatment technologies in all nutrient apparent digestibility and average daily weight gain. Therefore, it can be concluded that both treatments could serve as an alternative measure to improve nutritive value of finger millet straw, but due to environmental effect, EM treatment could be safe.

Enzymatic hydrolysis of hemicellulose from pretreated Finger millet (Eleusine coracana) straw by recombinant endo-1,4-ß-xylanase and exo-1,4-ß-xylosidase.

This study focuses on enzymatic saccharification of hemicellulose part of the pretreated Finger millet straw (FMS) for production of xylose. The variation in the carbohydrate composition of FMS was analysed when subjected to different pretreatments. The recombinant endo-1,4-ß-xylanase (CtXyn11A) was most active on the FMS pretreated with 1% (w/v) NaOH combined with oven heating at 120 °C for 20 min, resulting in a total reducing sugar yield (TRS) of 32 mg/g pretreated biomass. The pretreatment aided in concentrating the holocellulose content from 69.3% of raw powdered FMS to 76.4%. The post-treatment solid biomass yield was 0.36 g/g raw biomass. The two-step optimization of hemicellulose saccharification from the above pretreated FMS with i) endo-1,4-ß-xylanase (CtXyn11A) at 55 °C and ii) exo-1,4-ß-xylosidase (BoGH43A) at 37 °C, both at pH 7.5 by Box-Behnken design yielded the TRS of 70 mg/g pretreated biomass. The percentage conversion of xylan to xylose by CtXyn11A and BoGH43A was 24.7%.

Purification, identification and characterization of two novel antioxidant peptides from finger millet (Eleusine coracana) protein hydrolysate.

Antioxidant peptides were successfully identified from a finger millet protein hydrolysate. The trypsin hydrolysate showed a higher degree of hydrolysis (17.47 ±â€¯0.63%) than the pepsin hydrolysate, was further fractionated by ultrafiltration membrane [<3 kDa (UF3), 3-10 kDa (UF2) and > 10 kDa (UF1)]. UF3 with higher antioxidant activity (48.41 ±â€¯0.21%) was further fractionated into five fractions (GFA, GFB, GFC, GFD and GFE) using gel filtration. Fraction GFB possessed the highest antioxidant activity (61.79 ±â€¯0.08%) and was purified by reverse-phase ultra-flow liquid chromatography. Two potential antioxidant peptides were identified as TSSSLNMAVRGGLTR and STTVGLGISMRSASVR. Synthetic peptides with the same sequence were synthesized and characterized for their antioxidant activity. Molecular docking studies revealed that potential antioxidant activity from both peptides resulted from the interaction of serine and threonine residues with free radicals. The current study suggested that natural peptides identified from finger millet have potent antioxidant activity and regarded as a promising source for a functional food ingredient.

Profile of phenolic compounds and antioxidant activity of finger millet varieties.

The profiles of phenolic compounds and antioxidant capacities of four finger millet varieties harvested in northern Malawi were investigated. The total phenolics, flavonoids and condensed tannins in the free fractions ranged from 114.43 to 179.19 mg ferulic acid equivalent (FAE)/100 g, 90.24 to 202.94 mg catechin equivalent (CE)/100 g and 31.76 to 83.59 mg CE/100 g, respectively. Total phenolic contents of the bound fractions ranged from 58.27 to 123.23 mg FAE/100 g. Twenty phenolic compounds were identified in the free fractions including eighteen flavonoids, with catechin and epicatechin being the predominant flavonoids. Seventeen phenolic compounds were identified in the bound fractions, with ferulic acid being the predominant one. Ten of the identified polyphenols were firstly reported in finger millet. Darker colored finger millet varieties had higher phenolic contents and antioxidant properties than the lighter colored ones. Finger millet can be used as healthy food material and natural antioxidant resource.

Malting Period Effect on the Phenolic Composition and Antioxidant Activity of Finger Millet (Eleusine coracana L. Gaertn) Flour.

The present study examined the influence of malting on the phenolic composition of two cultivars of finger millet using an ultra-performance liquid chromatography mass spectrometer. Total polyphenols and antioxidant activities of the grains were also evaluated using sorghum as an external reference. Catechin, epicatechin, quercetin, taxifolin, and hesperitin were isolated flavonoids, whereas protocatechuic acid was the phenolic acid detected in finger millet malt. Increases in the content of catechin, epicatechin, and protocatechuic acid were observed for 72 h and 96 h for brown finger millet and sorghum malt. Complete loss of taxifolin and hesperitin were observed with the malting period for finger millet cultivars. A similar loss was noted in the proanthocyanidin A1/A2 and catechin content of sorghum with malting time. The grain malt exhibited 2,2-diphenyl-1-picrylhydrazyl,2,2'-azinobis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging and iron reducing activities. Increased ABTS and iron reducing activity with malting time were observed for the finger millet cultivars. The study demonstrates the presence of hesperitin in finger millet, and also shows that 72 h and 96 h of malting enhanced the catechin, epicatechin, and protocatechuic acid content, in addition to the antioxidant activity of the grain.

Carbon and nitrogen isotope variability in the seeds of two African millet species: Pennisetum glaucum and Eleusine coracana.

RATIONALE: A range of important small seeded C4 crops were domesticated in Africa, but little is known about their carbon and nitrogen isotope ratios (δ13 C and δ15 N values). Understanding natural isotopic variability within and among millets has the potential to help us to understand the conditions under which ancient cereals were grown and has significant implications for the interpretation of ancient diets based on stable isotope signatures. METHODS: We conducted carbon and nitrogen isotope analyses of modern and historical pearl millet (Pennisetum glaucum, n = 108) and finger millet (Eleusine coracana, n = 17) seed samples sourced from the United States Department of Agriculture as well as the Harlan Collection curated at the Crop Evolution Laboratory Herbarium at the University of Illinois. RESULTS: The millet species have significantly different mean carbon and nitrogen isotope ratios over broad temporal and spatial scales. We also found substantial isotopic variation within species (range of 1.9‰ and 8.5‰ in δ13 C and δ15 N values, respectively). Both water availability and growing season temperature significantly affected the P. glaucum δ13 C and δ15 N values; cumulative annual precipitation was positively correlated with both seed δ13 C and δ15 N values, while temperature was positively correlated with δ15 N values but negatively correlated with seed δ13 C values. CONCLUSIONS: The importance of both temperature and precipitation as predictors of δ13 C and δ15 N values in millets suggests that C4 plants may be more sensitive to environmental parameters than previously appreciated. Given the high degree of carbon and nitrogen isotope variability among accessions of these species, it is imperative that site-relevant plant isotope ratios are used for making isotope-based paleo-dietary predictions.

Some physical and functional properties of finger millet (Eleusine coracana) obtained in sub-Saharan Africa.

The study determined the physical properties of finger millet (FM) (Eluesine coracana) grains and the functional properties of FM flour. Physical properties such as colour attributes, sample weight, bulk density, true density, porosity, surface area, sample volume, aspect ratio, sphericity, dimensional properties and moisture content of grain cultivars were determined. Water absorption capacity (WAC), bulk density (BD), dispersibility, viscosity and micro-structure of FM flours were also evaluated. Data collected were analyzed using SPSS statistical software version 23.0. Results showed that milky cream cultivar was significantly higher (p<0.05) than other samples in sample weight, bulk density, true density, aspect ratio and sphericity. However, pearl millet, used as a control, was significantly different from FM flour on all dimensional properties. Moisture content of milky cream showed higher significant difference for both grains and flours as compared to brown and black grain/flours. Milky cream cultivar was significantly different in L*, b*, C*, H* values, WAC, BD and dispersibility for both FM grains and flours. Data showed that brown flour was significantly higher in viscosity than in milky and black flours. Microstructure results revealed that starch granules of raw FM flours had oval/spherical and smooth surface. The study is important for agricultural and food engineers, designers, scientists and processors in the design of equipment for FM grain processing. Results are likely to be useful in assessing the quality of grains used to fortify FM flour.

Uptake of phenolic compounds from plant foods in human intestinal Caco-2 cells.

In continuation of our studies on the bioaccessibility of phenolic compounds from food grains as influenced by domestic processing, we examined the uptake of phenolics from native/sprouted finger millet (Eleucine coracana) and green gram (Vigna radiata) and native/heat-processed onion (Allium cepa) in human Caco-2 cells. Absorption of pure phenolic compounds, as well as the uptake of phenolic compounds from finger millet, green gram, and onion, was investigated in Caco-2 monolayer model. Transport of individual phenolic compounds from apical compartment to the basolateral compartment across Caco-2 monolayer was also investigated. Sprouting enhanced the uptake of syringic acid from both these grains. Open-pan boiling reduced the uptake of quercetin from the onion. Among pure phenolic compounds, syringic acid was maximally absorbed, while the flavonoid isovitexin was least absorbed. Apparent permeability coefficient P(app) of phenolic compounds from their standard solutions was 2.02 x 10-6cm/s to 8.94 x 10-6cm/s. Sprouting of grains enhanced the uptake of syringic acid by the Caco-2 cells. Open-pan boiling drastically reduced the uptake of quercetin from the onion. The permeability of phenolic acids across Caco-2 monolayer was higher than those of flavonoids.

Evaluation of health potential of nutritionally enriched Kodo millet (Eleusine coracana) grown in Himachal Pradesh, India.

In this study, Kodo millet grains were phytochemically investigated for their nutritional and antioxidant potential for their use as functional foods. Methanolic extracts of grains showed higher phenolic content and antioxidant activity. TLC studies of the extracted polyphenols from kodo millet showed the predominant presence of ferulic acid and cinnamic acid in the millet. Further quantification of these polyphenols was done by using HPLC, analysing ferulic acid and cinnamic acid. Antagonistic spectrum of the polyphenols extracted showed inhibition against four bacterial test indicators viz. Staphylococcus aureus, Leuconostoc mesenteroides, Bacillus cereus and Enterococcus faecalis proving its antimicrobial action. The grains of kodo millet grains taken under study were found to posses' high protein, carbohydrates, minerals, crude fibers, polyphenols and antioxidants thus can be used as a good source of nutrition with additional health benefits.

Optimization of the malting process for nutritional improvement of finger millet and amaranth flours in the infant weaning food industry.

Malting is a beneficial approach to improve the nutritional value of cereals used in infant preparations. Malted finger millet and amaranth might be considered as potentially appropriate gluten-free alternatives for common wheat-based weaning products, especially in case of those suffering from celiac disease. In this study, the effects of germination temperature and duration on the main nutrients of malted finger millet and amaranth, are evaluated and optimized. Grains were germinated for 24, 36 and 48 h at 22, 26 and 30 °C. In the case of finger millet, germinating for 48 h at 30 °C resulted into 17% increase in protein availability, 10% increase in total energy and 60% reduction in resistant starch (RS). For amaranth, germinating for 48 h at 26 °C was preferable, resulting in 8% increase in protein availability, 11% increase in total energy, 70% reduction in RS and a 10% increase in the linoleic acid.

Effect of Fermentation and Cooking on Soluble and Bound Phenolic Profiles of Finger Millet Sour Porridge.

The aim of this study was to evaluate the soluble and bound phenolic content of finger millet and the impact of process induced changes on phenolic profiles of their sour porridge. Finger millet porridge and intermediate products were collected from four groups of households in the Hwedza communal area, Zimbabwe, after which soluble and bound phenolic compounds (PC) including condensed tannins (CT) were quantified. Bound PC and CT contributed 95% of the total PC and CT. The CT were only detected in the red varieties. Major individual PC identified were catechin occurring in the soluble fraction only, while ferulic, sinapic, and salicylic acid were mainly present in the bound fraction. Fermentation and cooking caused a more than 2-fold increase in soluble PC, CT, and individual PC. Improved traditional processing techniques optimized for improved bioavailability and health benefits of phenolics are highly relevant for the low income populations.

Identification and molecular characterization of 48 kDa calcium binding protein as calreticulin from finger millet (Eleusine coracana) using peptide mass fingerprinting and transcript profiling.

BACKGROUND: Attempts were made to identify and characterize the calcium binding proteins (CaBPs) in grain filling stages of finger millet using proteomics, bioinformatics and molecular approaches. RESULTS: A distinctly observed blue color band of 48 kDa stained by Stains-all was eluted and analyzed as calreticulin (CRT) using nano liquid chromatography-tandem mass spectrometry (nano LC-MS). Based on the top hits of peptide mass fingerprinting results, conserved primers were designed for isolation of the CRT gene from finger millet using calreticulin sequences of different cereals. The deduced nucleotide sequence analysis of 600 bp amplicon showed up to 91% similarity with CRT gene(s) of rice and other plant species and designated as EcCRT1. Transcript profiling of EcCRT1 showed different levels of relative expression at different stages of developing spikes. The higher expression of EcCRT1 transcripts and protein were observed in later stages of developing spikes which might be due to greater translational synthesis of EcCRT1 protein during seed maturation in finger millet. CONCLUSIONS: Preferentially higher synthesis of this CaBP during later stages of grain filling may be responsible for the sequestration of calcium in endoplasmic reticulum of finger millet grains.

Identification and characterization of calcium transporter gene family in finger millet in relation to grain calcium content.

Calcium (Ca) is an essential mineral for proper growth and development of plants as well as animals. In plants including cereals, calcium is deposited in seed during its development which is mediated by specialized Ca transporters. Common cereal seeds contain very low amounts of Ca while the finger millet (Eleusine coracana) contains exceptionally high amounts of Ca in seed. In order to understand the role of Ca transporters in grain Ca accumulation, developing seed transcriptome of two finger millet genotypes (GP-1, low Ca and GP-45 high Ca) differing in seed Ca content was sequenced using Illumina paired-end sequencing technology and members of Ca transporter gene family were identified. Out of 109,218 and 120,130 contigs, 86 and 81 contigs encoding Ca transporters were identified in GP-1 and GP-45, respectively. After removal of redundant sequences, a total of 19 sequences were confirmed as Ca transporter genes, which includes 11 Ca(2+) ATPases, 07 Ca(2+)/cation exchangers and 01 Ca(2+) channel. The differential expressions of all genes were analyzed from transcriptome data and it was observed that 9 and 3 genes were highly expressed in GP-45 and GP-1 genotypes respectively. Validation of transcriptome expression data of selected Ca transporter genes was performed on different stages of developing spikes of both genotypes grown under different concentrations of exogenous Ca. In both genotypes, significant correlation was observed between the expression of these genes, especially EcCaX3, and on the amount of Ca accumulated in seed. The positive correlation of seed mass with the amount of Ca concentration was also observed. The efficient Ca transport property and responsiveness of EcCAX3 towards exogenous Ca could be utilized in future biofortification program.