Synergistic effects of Trichoshield on enhancement of growth and resistance to downy mildew in pearl millet

Trichoshield, a talc formulation consisting of spores of Trichoderma harzianum, Trichoderma lignorum, Gliocladium virens and Bacillus subtilis was tested, following different application methods, for its ability to promote growth of pearl millet plants and to induce resistance to downy mildew of pearl millet. Under laboratory conditions, trichoshield seed treatment enhanced seed germination and seedling vigor of pearl millet significantly over the control; under greenhouse conditions vegetative growth parameters like height, fresh and dry weight, leaf area and number of tillers were significantly enhanced over the control: Trichoshield formulation offered greater protection against downy mildew in comparison with individual strains of T. harzianum, T. lignorum, G. virensand B. subtilis. Among the methods of application, foliar spray was found to be a more efficient delivery method than seed treatment or slurry treatment. Combinations of foliar spray with seed treatment and slurry treatment produced the same effect as foliar spray alone. Under field conditions, trichoshield treatment enhanced reproductive parameters like number of earheads, length and girth of earheads, 1000 seed weight and yield significantly over the control. Days required for 50% flowering was reduced by 4 days compared to the control. Yield enhancement of 28% over the control was highly significant. Trichoshield treatment offered protection ranging from 52 to 71% under field conditions, depending on the application method. However, the chemical fungicide metalaxyl Apron provided the highest protection against downy mildew, both under greenhouse and field conditions.     

Long-term treadmill exercise improves spatial memory of male APPswe/PS1dE9 mice by regulation of BDNF expression and microglia activation

Increasing evidence suggests that physical activity could delay or attenuate the symptoms of Alzheimer''s disease (AD). But the underlying mechanisms are still not fully understood. To investigate the effect of long-term treadmill exercise on the spatial memory of AD mice and the possible role of β-amyloid, brain-derived neurotrophic factor (BDNF) and microglia in the effect, male APPswe/PS1dE9 AD mice aged 4 months were subjected to treadmill exercise for 5 months with 6 sessions per week and gradually increased load. A Morris water maze was used to evaluate the spatial memory. Expression levels of β-amyloid, BDNF and Iba-1 (a microglia marker) in brain tissue were detected by immunohistochemistry. Sedentary AD mice and wildtype C57BL/6J mice served as controls. The results showed that 5-month treadmill exercise significantly decreased the escape latencies (P < 0.01 on the 4th day) and improved the spatial memory of the AD mice in the water maze test. Meanwhile, treadmill exercise significantly increased the number of BDNF-positive cells and decreased the ratios of activated microglia in both the cerebral cortex and the hippocampus. However, treadmill exercise did not significantly alleviate the accumulation of β-amyloid in either the cerebral cortex or the hippocampus of the AD mice (P > 0.05). The study suggested that long-term treadmill exercise could improve the spatial memory of the male APPswe/PS1dE9 AD mice. The increase in BDNF-positive cells and decrease in activated microglia might underpin the beneficial effect.     

Identification of a TcpC-TcpQ outer membrane complex involved in the biogenesis of the toxin-coregulated pilus of Vibrio cholerae

The toxin-coregulated pilus (TCP) of Vibrio cholerae and the soluble TcpF protein that is secreted via the TCP biogenesis apparatus are essential for intestinal colonization. The TCP biogenesis apparatus is composed of at least nine proteins but is largely uncharacterized. TcpC is an outer membrane lipoprotein required for TCP biogenesis that is a member of the secretin protein superfamily. In the present study, analysis of TcpC in a series of strains deficient in each of the TCP biogenesis proteins revealed that TcpC was absent specifically in a tcpQ mutant. TcpQ is a predicted periplasmic protein required for TCP biogenesis. Fractionation studies revealed that the protein is not localized to the periplasm but is associated predominantly with the outer membrane fraction. An analysis of the amount of TcpQ present in the series of tcp mutants demonstrated the inverse of the TcpC result (absence of TcpQ in a tcpC deletion strain). Complementation of the tcpQ deletion restored TcpC levels and TCP formation, and similarly, complementation of tcpC restored TcpQ. Metal affinity pull-down experiments performed using His-tagged TcpC or TcpQ demonstrated a direct interaction between TcpC and TcpQ. In the presence of TcpQ, TcpC was found to form a high-molecular-weight complex that is stable in 2% sodium dodecyl sulfate and at temperatures below 65°C, a characteristic of secretin complexes. Fractionation studies in which TcpC was overexpressed in the absence of TcpQ showed that TcpQ is also required for proper localization of TcpC to the outer membrane.     

Evaluation of free radical scavenging properties of two classical polyherbal formulations

Two polyherbal formulations of Ayurveda viz., Chandraprabha Vati and Maha yogaraja Guggulu were evaluated for their free radical scavenging properties. Methanolic extracts of the formulations were studied in four different in vitro and ex vivo models. Total phenolic content of Chandraprabha Vati and Maha yogaraja Guggulu was found to be 5.24% and 10.74% respectively. Methanolic extracts of the formulations were good scavengers of all the radicals but there was a difference in the activity of the two formulations in different models. Chandraprabha Vati was a good scavenger of superoxide radical and Maha yogaraja Guggulu was efficient in scavenging nitric oxide (NO), while both inhibited lipid peroxidation efficiently. Free radical scavenging activity of the different extracts can be attributed to the presence of various chemical components including phenolics.     

Vacuolar invertases in potato (Solanum tuberosum L.): molecular cloning, characterization, sequence comparison, and analysis of gene expression in the cultivars

In plants, vacuolar invertase (β-fructofuranosidase, EC 3.2.1.26) is known to play as a key modulator for hexose accumulation and cell expansion. In this study, two cDNA clones (2,013 and 1,945 bp, with 99 % sequence identity) encoding vacuolar invertase isoforms were isolated from a commercially important Indian potato cultivar, Kufri Chipsona-1 by RT-PCR. The corresponding predicted proteins consisted of 635 amino acids (designated as KC-VIN1, lacking a few amino acids at N-terminus) and 639 amino acids (designated as KC-VIN2), respectively. They showed 99 % identity, and found to vary at several locations with mostly non-conservative substitutions. Multiple sequence alignment of vacuolar invertase homologs covering four Solanaceae family members revealed some notable distinguishing sequence features (signature-type sequences). A consensus sequence was predicted using 45 vacuolar invertase sequences from 27 taxonomically different plant species, and a phylogenetic tree was generated to know the evolutionary relation between them. Hydrophobic characters were predicted, and compared in different plant species. All these data are presented in a comprehensive manner which were not documented in the earlier reports. As a preliminary study, vacuolar invertase expression patterns in the tubers of some Indian potato cultivars were analyzed by semi-quantitative RT-PCR and extractable enzyme assay. In all the potato cultivars, the overall expression level of invertase was found to be considerably higher after storage at low temperature as compared to the freshly harvested tubers.