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101.
Recently, greenhouse gas emissions have been of great concern globally. Ruminant livestock due to production of methane during normal fermentation in the rumen contributes substantially to the greenhouse effects. During the recent decade, a paradigm shift has been initiated whether plant secondary metabolites (PSM) could be exploited as natural safe feed additives alternative to chemical additives to inhibit enteric methanogenesis. More than 200,000 defined structures of PSM have been known. Some plants or their extracts with high concentrations of bioactive PSM such as saponins, tannins, essential oils, organosulphur compounds, flavonoids and many other metabolites appear to have potential to inhibit methane production in the rumen. The possible mechanisms and effects of many PSM on rumen methanogenesis are not clearly understood. Saponins may decrease methanogenesis through the inhibition of rumen protozoa and in turn may suppress the numbers and activity of methanogens. Although the direct effect of saponins on methanogens has not been demonstrated, saponins might inhibit methanogens at high doses. Tannins may inhibit the methanogenesis directly and also via inhibition of protozoal growth. Essential oils, organosulphur compounds and flavonoids appear to have direct effects against methanogens, and a reduction of protozoa associated methanogenesis probably plays a minor role for these metabolites. The chemical structure and molecular weight of the PSM and chemical composition of diets dependent upon the different feeding regimes may influence the effects of PSM on methane production. Although PSM may negatively affect nutrient utilization, there is evidence that methanogenesis could be suppressed without adversely affecting rumen fermentation, which could be exploited to mitigate methane emission in ruminants. 相似文献
102.
Subrata Patra 《Inorganica chimica acta》2010,363(8):1639-135
Metalloreceptors containing ruthenium(II) bipyridine unit as fluorophore and pendant macrocyclic units as ionophore have been synthesized and their luminescence and electrochemical properties have been investigated. Ion-binding study of these fluoroionophore with the anions F−, Cl−, Br−, I−, , , , , CH3COO−, and and cations Na+, K+, Mg2+, Ca2+, Zn2+, Ba2+, Sr2+ Cd2+, Hg2+, Pb2+ and Cu2+, monitored by luminescence and 1H NMR spectral changes, reveal strong interactions of and F− for 2 and 3 and of Cu2+ only for 3. Luminescence titrations for 2 and 3 have been carried out to determine binding constants (Ks), and the calculated values are in the range 2.85 × 102 to 4.48 × 104 M−1. The 1H NMR spectral changes for 2 and 3 with the addition of increasing concentration of F− and exhibit substantial low-field shift of the CONH proton indicating its involvement in complex formation with the anions. The adduct of 2 and 3 have been isolated and characterized by 1H and 31P NMR, mass and IR spectroscopy. The results are discussed in light of selectivity, structures of the anion bound complexes and their luminescence property. 相似文献
103.
Patra AK Abbadie L Clays-Josserand A Degrange V Grayston SJ Guillaumaud N Loiseau P Louault F Mahmood S Nazaret S Philippot L Poly F Prosser JI Le Roux X 《Environmental microbiology》2006,8(6):1005-1016
Management by combined grazing and mowing events is commonly used in grasslands, which influences the activity and composition of soil bacterial communities. Whether observed effects are mediated by management-induced disturbances, or indirectly by changes in the identity of major plant species, is still unknown. To address this issue, we quantified substrate-induced respiration (SIR), and the nitrification, denitrification and free-living N(2)-fixation enzyme activities below grass tufts of three major plant species (Holcus lanatus, Arrhenatherum elatius and Dactylis glomerata) in extensively or intensively managed grasslands. The genetic structures of eubacterial, ammonia oxidizing, nitrate reducing, and free-living N(2)-fixing communities were also characterized by ribosomal intergenic spacer analysis, and denaturing gradient gel electrophoresis (DGGE) or restriction fragment length polymorphism (RFLP) targeting group-specific genes. SIR was not influenced by management and plant species, whereas denitrification enzyme activity was influenced only by plant species, and management-plant species interactions were observed for fixation and nitrification enzyme activities. Changes in nitrification enzyme activity were likely largely explained by the observed changes in ammonium concentration, whereas N availability was not a major factor explaining changes in denitrification and fixation enzyme activities. The structures of eubacterial and free-living N(2)-fixing communities were essentially controlled by management, whereas the diversity of nitrate reducers and ammonia oxidizers depended on both management and plant species. For each functional group, changes in enzyme activity were not correlated or were weakly correlated to overall changes in genetic structure, but around 60% of activity variance was correlated to changes in five RFLP or DGGE bands. Although our conclusions should be tested for other ecosystems and seasons, these results show that predicting microbial changes induced by management in grasslands requires consideration of management-plant species interactions. 相似文献
104.
105.
Prashanta Kumar Panda Srimanta Patra Prajna Paramita Naik Prakash Priyadarshi Praharaj Subhadip Mukhopadhyay Biswa Ranjan Meher Piyush Kumar Gupta Rama S. Verma Tapas K. Maiti Sujit K. Bhutia 《Journal of cellular physiology》2020,235(3):2776-2791
Therapy-induced senescence in cancer cells is an irreversible antiproliferative state, which inhibits tumor growth and is therefore a potent anti-neoplastic mechanism. In this study, low doses of Abrus agglutinin (AGG)-induced senescence through autophagy in prostate carcinoma cells (PC3) and inhibited proliferation. The inhibition of autophagy with 3-methyl adenine reversed AGG-induced senescence, thus confirming that AGG-triggered senescence required autophagy. AGG treatment also led to lipophagy-mediated accumulation of free fatty acids (FFAs), with a concomitant decrease in the number of lipid droplets. Lalistat, a lysosomal acid lipase inhibitor, abrogated AGG-induced lipophagy and senescence in PC3 cells, indicating that lipophagy is essential for AGG-induced senescence. The accumulation of FFAs increased reactive oxygen species generation, a known facilitator of senescence, which was also reduced in the presence of lalistat. Furthermore, AGG upregulated silent mating type information regulator 2 homolog 1 (SIRT1), while the presence of sirtinol reduced autophagy flux and the senescent phenotype in the AGG-treated cells. Mechanistically, AGG-induced cytoplasmic SIRT1 deacetylated a Lys residue on the cytoplasmic domain of lysosome-associated membrane protein 1 (LAMP1), an autolysosomal protein, resulting in lipophagy and senescence. Taken together, our findings demonstrate a novel SIRT1/LAMP1/lipophagy axis mediating AGG-induced senescence in prostate cancer cells. 相似文献
106.
Patra A Batra S Bhaduri AP Khanna A Chander R Dikshit M 《Bioorganic & medicinal chemistry》2003,11(10):2269-2276
The synthesis of isoxazole-based derivatives utilizing Baylis-Hillman chemistry and results of their preliminary bioevaluation as hypolipidemic agents in triton model are described. 相似文献
107.
108.
109.
Anne Kathrin Müller-Rischart Anna Pilsl Patrick Beaudette Maria Patra Kamyar Hadian Maria Funke Regina Peis Alexandra Deinlein Carolin Schweimer Peer-Hendrik Kuhn Stefan F. Lichtenthaler Elisa Motori Silvana Hrelia Wolfgang Wurst Dietrich Trümbach Thomas Langer Daniel Krappmann Gunnar Dittmar Konstanze F. Winklhofer 《Molecular cell》2013,49(5):908-921
Highlights? The stress-protective prosurvival activity of parkin depends on NEMO ? Parkin binds to LUBAC and increases linear ubiquitination of NEMO ? OPA1 is upregulated via parkin/NEMO/NF-κB for maintaining mitochondrial integrity ? TNF-α signaling via NEMO/NF-κB is impaired in parkin-deficient cells 相似文献
110.