A standardized protocol for genomic DNA isolation from Terminalia arjuna for genetic diversity analysis

For studying genetic diversity in natural populations of Terminalia , a medicinal plant, our attempts to isolate high quality DNA using several previously reported protocols and even modifications were unsuccessful. We therefore combined CTAB based isolation, and column based purification step, to isolate DNA from Terminalia arjuna . The DNA isolated using this standardized protocol was high in quality and suitable for restriction digestion and generation of random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP)

Hydroxy-benzimidazoles as blue-green emitters: Synthesis, structural and DFT studies

The new benzimidazole ligands (3a-e) were synthesized using ethyl 4-(butylamino)-3-nitrobenzoate and substituted salicylaldehyde in the presence of sodium dithionite reagent which undergoes ``one-pot'' nitro reductive cyclization. Here benzimidazole moiety acts as an electron-acceptor (A) whereas substituted 2-hydroxyphenyl moiety acts as an electron-donor (D) unit. The molecular structures were characterised by FTIR, H-1 NMR, C-13 NMR, single crystal XRD and MS analysis. Optoelectronic properties were determined by UV-vis, solution and solid photoluminescence, quantum yield and lifetime. The solvent-dependent absorption and emission were studied using both polar protic and polar aprotic solvents. All the derivatives exhibited ESIPT, especially compound ethyl 1-butyl-2-(3,5-dichloro-2-hydroxyphenyl)-1H-benzod]imidazole-5-carbox ylate (3e) displayed dual emission in both polar protic and polar aprotic solvents. The compound stability and electrochemical property were determined by thermal gravimetric analysis (TGA) and cyclic voltammetry (CV) respectively. The compounds emit intense blue-green fluorescence with high to moderate quantum yield. Also, these derivatives exhibited a high Stokes shift. The computational studies like Density-Functional Theory (DFT) and Molecular Electrostatic Potential (MEP) were conducted to provide important insights into the structure-property relationships. The crystal packing is stabilized through intermolecular hydrogen bonds (C-H center dot center dot center dot O) and intermolecular interactions (pi center dot center dot center dot pi). The findings of results help in developing novel ligands in the field of organic optoelectronics

Green Synthesis of Silver Nanoparticles by C ytobacillus firmus Isolated from the Stem Bark of Terminalia arjuna and Their Antimicrobial Activity

This work reports an eco-friendly synthesis of silver nanoparticles (AgNPs) using endophytic bacteria, Cytobacillus firmus isolated from the stem bark of Terminalia arjuna. The synthesis of AgNPs was confirmed by visual observation as a change in color of the bacterial solution impregnated with silver. Further, the morphology of the AgNPs, average size, and presence of elemental silver were characterized by UV–Visible spectroscopy, scanning electron microscopy, and dynamic light scattering spectroscopy. The roles of endophytic secondary metabolites in the metal reduction, stabilization, and capping of silver nanoparticles were studied by qualitative FTIR spectral peaks. The antimicrobial ability of AgNPs was evaluated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria and pearl millet blast disease-causing fungi (Magnoporthe grisea). The biosynthesized AgNPs showed good antibacterial and antifungal activities. AgNPs effectively inhibited the bacterial growth in a dose-dependent manner and presented as good antifungal agents towards the growth of Magnoporthe grisea

Studies of the mesomorphic behavior of bivalent carbohydrate amphiphiles

A homologous series of bivalent glycolipids constituted of 1,3-bis-O-($\beta$-D-glucopyranosyl)-2- O-alkyl glycerol, bearing two sugar head groups and one alkyl chain on a glycerol backbone, was synthesized. The mesomorphic behaviour was investigated with the aid of polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction methods. The homologous members exhibit a smectic A phase, consistently with a partial bilayer structure. From experimental d-spacing and computationally derived length of the molecules, it is suggested that a partial interdigitation of the molecules is present in the bilayer structure

Effect of the C-2 hydroxyl group on the mesomorphism of alkyl glycosides: synthesis and thermotropic behavior of alkyl 2-deoxy-d-arabino-hexopyranosides

A homologous series of alkyl 2-deoxy-α-D-arabino-hexopyranosides and alkyl 2-deoxy-β-D-arabino-hexopyranosides were synthesized, upon glycosylation of 1-alkanols (from C<SUB>8</SUB> to C<SUB>18</SUB> alkanols) with ethyl 2-deoxy-3,4,6-tri-Ο-acetyl-1-thio-d-arabino-hexopyranoside, followed by a deprotection. The thermotropic behavior of these new types of alkyl glycosides was investigated. It was observed that the β-anomers of these alkyl glycosides, bearing nonyl to tetradecyl alkyl chain are mesomorphic, exhibiting monotropic smectic A phase. In contrast, the α-anomers are all non-mesomorphic. An effort to identify the liquid crystalline behavior of binary mixtures of the α - and β-anomers was undertaken and it was found that mixtures containing equimolar amounts of the anomers exhibited mesomorphic behavior. A fine balance of the hydrophilic and hydrophobic components within the molecule is also found to be important for the alkyl 2-deoxy glycosides to form the mesophase

Role of hydroxyl group on the mesomorphism of alkyl glycosides: synthesis and thermal behavior of alkyl 6-deoxy-β-D-glucopyranosides

A homologous series of alkyl 6-deoxy-β-D-glucopyranoside amphiphiles was prepared, in an effort to identify the role of hydroxyl group in the mesomorphic behavior of alkyl glycosides. Synthesis was performed by a chlorination of the sugar moiety in alkyl β-D-glucopyranosides with methylsulfonyl chloride in DMF, followed by a metal mediated dehalogenation to secure alkyl 6-deoxy-β-D-glucopyranosides, wherein the alkyl chain length varied from C<SUB>9</SUB> to C<SUB>16</SUB>. The mesomorphic behavior of these 6-deoxy alkyl glycosides was assessed using polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction method. Whereas the lower homologues exhibited a monotropic SmA phase till sub-ambient temperatures, the higher homologues formed a plastic phase. A partial interdigitized bilayer structure of SmA phase is inferred from experimental d-spacing and computationally derived lengths of the molecules. The results were compared with those of normal alkyl glucopyranosides, retained with hydroxyl groups at C-2-C-6 carbons, and alkyl 2-deoxy-glucopyranosides, devoid of a hydroxyl group at C-2 and the comparison showed important differences in the mesomorphic behavior

Effect of the C-2 hydroxyl group on the mesomorphism of alkyl glycosides: synthesis and thermotropic behavior of alkyl 2-deoxy-D-arabino-hexopyranosides

A homologous series of alkyl 2-deoxy-α-d-arabino-hexopyranosides and alkyl 2-deoxy-β-d-arabino-hexopyranosides were synthesized, upon glycosylation of 1-alkanols (from C8 to C18 alkanols) with ethyl 2-deoxy-3,4,6-tri-O-acetyl-1-thio-d-arabino-hexopyranoside, followed by a deprotection. The thermotropic behavior of these new types of alkyl glycosides was investigated. It was observed that the β-anomers of these alkyl glycosides, bearing nonyl to tetradecyl alkyl chain are mesomorphic, exhibiting monotropic smectic A phase. In contrast, the α-anomers are all non-mesomorphic. An effort to identify the liquid crystalline behavior of binary mixtures of the α- and β-anomers was undertaken and it was found that mixtures containing equimolar amounts of the anomers exhibited mesomorphic behavior. A fine balance of the hydrophilic and hydrophobic components within the molecule is also found to be important for the alkyl 2-deoxy glycosides to form the mesophase