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Sweet sorghum Sorghum bicolor (L.) Moench) is a promising crop for bioethanol production characterized by its high biomass yield, sugar-rich stalks, facile juice extraction, and ability to adapt to different production systems. The objective of this study was to assess the effects of cultivation practices (soil treatments) on the juice, sugar, and ethanol yields of sweet sorghum variety Roger. Three methods of tillage (minimum, traditional, and traditional tillage with rupture of the plow layer) and three types of fertilizers (inorganic, organic, and without fertilizer) were assayed. The best results of stem yield (44.3 tons/ha), juice production (25.6 m3/ha), concentration of soluble solids in the juice (16.9 °Brix), and juice ethanol yield (2.1 m3/ha) were obtained under a mixture of traditional plowing with plow layer breaking, applying an organic fertilizer. In addition, the extracted juice allowed yeast (industrial Saccharomyces cerevisiae PE-2) growth and conversion to ethanol without the need for nutrients supplementation. Therefore, sweet sorghum continues to be an interesting bioenergetic crop for production of first-generation biofuels. [ABSTRACT FROM AUTHOR]

The aim of this study was the characterization of chromatic, nutritional and nutraceutical properties of fifteen native maize genotypes of the races: conico norteño, elotes cónicos, raton, conico norteño × elotes cónicos, raton × elotes cónicos, Celaya × elotes cónicos, elotes cónicos × conico norteño from the northeast of Mexico. The results showed that the values of the color parameters L*, C* and h in genotypes range from 25.13 to 63.64, 2.41 to 33.58 and 14.36 to 359.19, respectively. The percentage of nutritional component varied from carbohydrates (71.30–74.88), protein (9.72–12.57) and moisture (7.98–9.67). The samples were rich in P, K, Mg, Zn and Fe. The total phenols content (free + bound) ranged from 349.39 to 485.71 mgGAE/100 g, showing bound fractions higher content than free fractions. The total flavonoids (free + bound) were from 24.00 to 105.75 mgCE/100 g, and for eight of the genotypes the bound fractions were higher than free fractions. Condensed tannins were only found in free fractions with values ranging from 33.70 to 158.55 mgCE/100 g. Total anthocyanins ranged from 1.38 to 74.52 mgC3GE/100 g. In HPLC analysis, ferulic acid (103.34–164.90 mg/100 g) was the main phenolic compound followed by coumaric acid (5.57–15.52 mg/100 g) and they were only identified in bound extracts. Finally, the antioxidant capacity (free + bound) expressed in µmolTE/100 g was from 1127.70 to 1875.70, 2826.90 to 4263.90, 730.94 to 1340.65 and 3484.80 to 5592.60 in DPPH, ABTS, FRAP and ORAC, respectively, and IC50 to DPPH and ABTS were expressed in mg/mL. In conclusion, significant correlation was found between chromatic versus antioxidant capacity, and anthocyanin content. In addition, higher phenolic content were found in bound extracts, and a genetic diversity was observed between maize genotypes. [ABSTRACT FROM AUTHOR]

Environmental risk assessment (ERA) of genetically modified (GM) crops is a process to evaluate whether the biotechnology trait(s) in a GM crop may result in increased pest potential or harm to the environment. In this analysis, two GM insect-resistant (IR) herbicide-tolerant maize hybrids (MON-89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6) and one herbicide-tolerant GM hybrid (MON-ØØ6Ø3-6) were compared with conventional maize hybrids of similar genetic backgrounds. Two sets of studies, Experimental Phase and Pilot Phase, were conducted across five ecological regions (ecoregions) in Mexico during 2009-2013, and data were subject to meta-analysis. Results from the Experimental Phase studies, which were used for ERA, indicated that the three GM hybrids were not different from conventional maize for early stand count, days-to-silking, days-to-anthesis, root lodging, stalk lodging, or final stand count. Statistically significant differences were observed for seedling vigor, ear height, plant height, grain moisture, and grain yield, particularly in the IR hybrids; however, none of these phenotypic differences are expected to contribute to a biological or ecological change that would result in an increased pest potential or ecological risk when cultivating these GM hybrids. Overall, results from the Experimental Phase studies are consistent with those from other world regions, confirming that there are no additional risks compared to conventional maize. Results from Pilot Phase studies indicated that, compared to conventional maize hybrids, no differences were detected for the agronomic and phenotypic characteristics measured on the three GM maize hybrids, with the exception of grain moisture and grain yield in the IR hybrids. Since MON-89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6 confer resistance to target insect pests, they are an alternative for farmers in Mexico to protect the crop from insect damage. Additionally, the herbicide tolerance conferred by all three GM hybrids enables more cost-effective weed management. [ABSTRACT FROM AUTHOR]

The high capacity of the chloroplast genome to integrate and express transgenes at high levels makes transplastomic technology a good option for overexpressing proteins of interest. This report presents the stable expression of β-glucosidase ( bgl1 gene) from Aspergillus niger and two cellulases ( celA and celB genes) from Thermotoga neapolitana into the chloroplast genome of tobacco. The pES6, pHM4, pHM5 and pHM6 vectors were derived from the pES4 plasmid containing bgl1, celA- celB, celA and celB synthetic genes, respectively. All of the genes were flanked by a synthetic rrn16 promoter and the 3′UTR from rbcL gene. The integration of the genes into intergenic regions rrn16 and 3′rps12 of the inverted repeats was confirmed by Southern blot analysis. Stable expression and processing of monocistronic mRNA were confirmed by Northern blot analysis, and protein functionality was analysed via enzymatic activity assay. The recombinant enzymes exhibited high enzymatic activity at pH 5 ( β-glucosidase: 30.45 U mg of TSP, celA-celB 58 U mg of TSP, celA 49.10 U mg of TSP and celB 48.72 U mg of TSP). In addition, β-glucosidase exhibited high activity at 40 °C, whereas cellulases type A (celA) and type B (celB) showed high activity at 65 °C. NtpES6, NtpHM5 and NtpHM6 plants showed a similar phenotype compared with the wild type plants; however, NtpHM4 plants presented an abnormal phenotype with variegated leaves. This study, demonstrated that hydrolytic genes such as bgl1, celA and celB could be integrated and expressed correctly in the chloroplast genome. This work provides new information on methods and strategies for the expression of hydrolytic enzymes that are potentially useful for biotechnological applications using transplastomic plants. [ABSTRACT FROM AUTHOR]