Carbon nanotube (CNT) reinforced hydroxyapatite (HAp) composites were fabricated by using the spark plasma sintering process with surfactant modified CNT and HAp nano powder. Without the dependency on sintering temperature, the main crystal phase existed with the HAp phase although a few contents of (Tri calcium phosphate) phase were detected. The maximum fracture toughness, was obtained in the sample sintered at and on the fracture surface a typical intergranular fracture mode, as well as the pull-out pmhenomenon of CNT, was observed.

Seed storage proteins are used as carbon and nitrogen sources for the nutritional improvement of seeds. Since the composition of proteins from the Korean cultivars of proso millet is unknown, this study was conducted to obtain a reference map of millet seed proteins and identify the functional characteristics of the identified proteins. Proteins extracted from proso millet seeds of various cultivars were investigated using proteomic techniques such as 2-D electrophoresis coupled with mass fingerprinting; 1152 (differentially expressed) protein spots were detected on the 2-D gels. Among them, 26 reproducible protein spots were analyzed using matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry. Out of the 26 proteins, 2 proteins were upregulated in all the millet cultivars, while 13 proteins were upregulated and 11 proteins were downregulated in 2 cultivars. Abundance of most of the identified protein species associated with polysaccharide and starch metabolism, transcription, and pathogenesis was significantly enhanced, while that of other protein species involved in glycolysis, stress response, and transduction was severely reduced. Taken together, the results suggest that the differential expression of the proteins from the four millet cultivars may be cultivar-specific. By conducting a proteomic investigation of millet seeds from different cultivars, we sought to better understand the functional categorization of individual proteins on the basis of their molecular functions. We believe that the identified proteins may help in investigating genetic variations in millet cultivars.

Cadmium (Cd) pollution is thought to be one of the leading threat to the environment due to its high toxicity. However, the molecular responses induced by Cd have so far been grossly overlooked. This study examines the morpho-physiological alterations combined with proteome changes in leaves of Sorghum bicolor when exposed to Cd. Ten days old sorghum seedlings were exposed to different concentrations (0, 100, and 150 μM) of CdCl2 and a significant accumulation of Cd in the leaves was recorded by ICP analysis. Furthermore, the effects of Cd exposure on protein expression patterns in S. Bicolor was investigated by two-dimensional gel electrophoresis (2-DE) and the 2-DE profile of leaf proteins from both control and Cd-treated seedlings were compared quantitatively using Progenesis SameSpot software. Results lined to morphological changes that plants treated with Cd suffered reduction of growth. The concentration of Cd was markedly reversed by the Cd treatments, whereas the absorption degree of Cd was increased by the higher concentration of Cd by confocal microscopy. Using 2-DE method, a total of 33 differentially expressed protein spots were identified by MALDI-TOF-TOF mass spectrometry. Of those, 13 protein spots were significantly enhanced/reduced while 20 reduced under Cd treatment. The most of the up-regulated proteins are involved in oxidative response, glutathione and sulfur metabolism as well as the secondary metabolite biosynthesis. Collectively, our study provides insights into the integrated molecular mechanisms of early responses to Cd and growth and physiological characteristics of sorghum seedlings hoping to provide references on the mechanism of heavy metal damaging plants.

Copper (Cu) is an essential micronutrient required for growth and development of plants. But, at a high concentration in soil, copper acts as a major toxic element to plant cells due to its potential inhibitory effects against many physiological and biochemical processes. In this study, the morphological and physiological changes were observed in the leaf of sorghum plants treated with different concentrations (0, 100, and 150 μM) of Copper (Cu). The results linked to morphological changes that plants treated with Cu suffered reduction in growth and morphological changes. In the ion concentration investigation, the concentrations of Cu2+ increased, the concentration of others interacting ions (Zn2+, Ca2+, Mn2+, Fe2+) were changed dramatically. For proteome analysis, 2-D combined with MALDI-TOF-TOF mass spectrometry was performed. Two dimensional gels stained with silver staining, a total of 422 differential expressed proteins (≥ 2-fold) were identified using Progenesis SameSpot software. A total of 24 spots from Cu-induced sorghum leaf and 21 spots from Cu-induced sorghum root were analyzed by mass spectrometry. Out of 24 protein spots from Cu-stressed leaf, of which 16 protein spots were up-regulated and 8 protein spots were down-regulated whereas out of 21 protein spots, a total of 9 protein spots were up-regulated and 12 spots were down-regulated from Cu-stressed root. Taken together, these studies revealed the effects of heavy metal, Cu on the growth and physiological characteristics in sorghum seedlings and proteome investigation, hoping to provide references on the mechanism of heavy metal damaging plants.

Among the abiotic stresses, heavy metal (HM) toxicity is thought to be one of the major abiotic stresses leading to hazardous effects in plants. In spite of its potential physiological and economical significance, morphological alterations induced by heavy metals in plants have so far been grossly overlooked. In the present study, the morphological and physiological changes were observed in the leaf of sorghum plants treated with different concentrations (0, 50, 100, and 150 μM) of CdCl2. Results revealed that plants endured reduction in growth and morphological changes amazingly altered by cadmium. The growth of sorghum seedlings treated with 150 μM cadmium was more inhibited than that of sorghum seedlings treated with 100 μM Cd, 50μM and non-treated plants. The morphological characteristics revealed that the cadmium stress inhibited the root and shoot elongation after growing the rise seedling in the presence of cadmium. In the case of ion concentration, the concentrations of Zn2+, Ca2+ were decreased whereas Fe2+ concentration was increased except 100 μM under cadmium stress. In confocal microscopy, results showed that the absorption degree of cadmium was increased by the higher concentration of cadmium. The fluorescence intensity of cadmium was also increased. Thus, it seemed that cadmium has an influence on sorghum in the case of early stages of sorghum. This study reported the effects of heavy metal, cadmium on the growth and physiological characteristics of sorghum seedlings, hoping to provide references on the mechanism of heavy metal damaging plants, and phyto-remediation for heavy metal polluted soil.

Grain sorghum (Sorghum bicolor) is a major staple for a large portion of the world. The crop ranks fifth among the cereals world-wide with respect to its importance for food and feed applications. To this end, the grain harvested from sorghum, and the millets provides an important source for dietary calories and protein for approximately one billion people in the semi-arid regions of the world. However, grain sorghum products are known to have relatively poor digestibility, only approximately 50%–70%, in comparison with other grains, such as wheat and maize, which tend to have digestibility percentages over 80% and 70%, respectively. Protein with high digestibility is by definition nutritionally superior owing to the increased availability of amino acids. Digestibility can be impacted by both protein–protein and⁄or protein–nonprotein interactions. However, with respect to grain sorghum, it is thought that the major factor influencing digestibility is the former because of high protein cross-linking around the protein body. To understand the mechanism of seed storage proteins in the sorghum, the proteomic analysis was carried out between the wild(BTX623) and mutant(M271207) genotypes of sorghum. Proteins were separated from the mature seed using IEF in the first-dimension and SDS-PAGE in the second dimension along with hybrid LTQ-FTICR mass spectrometry. After image analysis using Progenesis SameSpot software, we identified the 62 differential expressed protein spots out of 293 protein spots. Out of total differential expressed spots, 35 differential expressed protein spots (more than2-fold) were analyzed by mass spectrometry. Out of 35 protein spots, we were identified 20 protein spots as up-regulated and 15 protein spots as downregulated, significantly. In our proteomic investigation, the candidate proteins may provide novel clues for better understanding the characteristics of seed proteins in Sorghum.