Seed biopriming with antagonistic microbes and ascorbic acid induce resistance in tomato against Fusarium wilt.

Seed biopriming is an emerging technique to enhance seed germination under stress conditions. An integrated approach of tomato seed biopriming with ascorbic acid, Trichoderma asperellum BHU P-1 and Ochrobactrum sp. BHU PB-1 was applied to observe the response against wilt pathogen of tomato Fusarium oxysporum f. sp. lycopersici (FOL). Tomato seeds bioprimed with the aforementioned application expressed augmented seed germination and activated of defense response. Seed germination was recorded higher (80 %) at low concentration (1 pM) of ascorbic acid as compared to high concentration of 1 mM (41 %). Combination of both ascorbic acid and antagonistic microbe treatments (T5 & T6) significantly reduced disease incidence (up to 28 %) in tomato plants at 10 days. T5 and T6 treated plants exhibited higher accumulation of total phenol content and increased activity of Phenylammonia lyase (PAL), Peroxidase (PO), Chitinase (Chi) and Polyphenol oxidase (PPO) as compared to control (T1) plants. ROS formation in the form of H2O2 was also found to be reduced in combined treatment. Histochemical analysis revealed that phenylpropanoid pathway (lignin deposition) was more activated in combined priming treatment plants as compared to individual treatment upon challenge inoculation with FOL. Transcript expression analysis of defense genes confirmed the up-regulation of PAL (2.1 fold), Chi (0.92 fold), Pathogenesis related proteins (PR) (1.58 fold) and Lipoxygenase (Lox) (0.72 fold) in T6 treatment as compared to T1 treatment plants at 96 h. This study reveals that ascorbic acid treatment with antagonistic microbes through seed priming effectively induced seed germination and elicited defense mechanism to control wilt disease in tomato plants.

Piperidine-4-methanthiol ester derivatives for a selective acetylcholinesterase assay.

The activity of acetylcholinesterase (AChE) is measured to obtain pathological information about the cholinergic system in various disease states and to assess the effect of AChE inhibitors. Using Ellman's method that is commonly used in such examinations, butyrylcholinesterase inhibitors must be added to measure AChE-specific activity because of low selectivity of AChE toward traditional substrates; however, such inhibitors also inhibit AChE. Therefore, it is desirable to obtain an AChE selective substrate that can be used with the Ellman's method. Here, we synthesized novel AChE substrates, 1-methyl-4-acetylthiomethylpiperidine and 1,1-dimethyl-4-acetylthiomethylpiperidine, and evaluated the hydrolysis rate and AChE selectivity by comparison with the results obtained when traditional substrates were used. The hydrolysis rate of the novel compounds by human AChE was one order of magnitude lower than that of the traditional substrates, acetylthiocholine and acetyl-beta-methylthiocholine, whereas the hydrolysis rate using human butyrylcholinesterase was two orders of magnitude lower than that of the traditional substrates. This indicated that AChE showed selectivity towards the novel substrates which was one order of magnitude higher than that of the traditional substrates. The hydrolysis of the novel compounds in a rat cerebral cortical homogenate and a monkey whole blood was completely inhibited by 1 muM of the specific AChE inhibitor, 1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one, indicating the high specificity of AChE towards the novel substrates in a crude tissue sample. From these results, we conclude that the novel compounds developed would be suitable AChE-selective substrates for Ellman's method.

Thermodynamic functions of molecular conformations of (2-fluoro-2-phenyl-1-ethyl)ammonium ion and (2-hydroxy-2-phenyl-1-ethyl)ammonium ion as models for protonated noradrenaline and adrenaline: first-principles computational study of conformations and thermodynamic functions for the noradrenaline and adrenaline models.

This paper reports the structural and thermodynamic consequences of substitution of the OH group by the isoelectronic F-atom in the case of the adrenaline family of molecules. The conformational landscapes were explored for the two enantiomeric forms of N-protonated-beta-fluoro-beta-phenyl-ethylamine, also called (2-fluoro-2-phenyl-1-ethyl)-ammonium ion (Model 1) and that of N-protonated-beta-hydroxy-beta-phenyl-ethylamine, also referred to as (2-hydroxy-2-phenyl-1-ethyl)-ammonium (Model 2) models of noradrenaline and adrenaline molecules. These full conformational studies were carried out by first principles of quantum mechanical computations at the B3LYP/6-31G(d,p) and G3MP2B3 levels of theory, using the Gaussian03 program. Also, frequency calculations of the stable structures were performed at the B3LYP/6-31G(d,p), and G3MP2B3 levels of theory. The thermodynamic functions (U, H, S, and G) of the various stable conformations of the title compounds were calculated at these levels of theory for the R and S stereoisomers. Relative values of the thermodynamic functions have been calculated with respect of the chosen reference conformers in which all relevant dihedral angles assumed anti orientation for the Model 1 and Model 2. Through the combination of both point and axis chirality, the enantiomeric and diastereomeric relationships of the six structures for each molecule investigated were established. Intramolecular hydrogen bonding interactions have been studied by the atoms in molecules (AIM) analysis of the electron density. The aromaticity of phenyl group has been determined by a selective hydrogenation protocol. The pattern of the extent of aromacity, due intramolecular interactions, varies very little between the two models studied.