Ahi Evran University

About: Ahi Evran University is a education organization based out in Kırşehir, Turkey. It is known for research contribution in the topics: Density functional theory & Ab initio. The organization has 842 authors who have published 2270 publications receiving 21904 citations.

Elicitor induced stevioside production, in vitro shoot growth, and biomass accumulation in micropropagated Stevia rebaudiana

Abstract: For the purpose of enhancing the secondary metabolite content in micropropagated Stevia rebaudiana plants without inhibiting plant growth, node explants were cultured on woody plant medium (WPM) containing alginate (ALG), casein hydrolysate (CH), pectin (PEC), yeast extract (YE), methyl jasmonate (MeJA), salicylic acid (SA), or chitosan (CHI). The highest shoot number; shoot length, node number, and leaf number; leaf length; and stem diameter were observed on WPM containing 1.0 g/L YE; 100 µM CHI; 0.5 g/L CH; and 1.0 g/L ALG, respectively. The root regeneration frequency reached 100 % on WPM supplemented with 0.5, 1.0, or 2.0 g/L PEC, 1.0 g/L YE, or 50 µM CHI and the control. The highest root number was obtained on WPM containing 0.5 g/L PEC, while the longest root length was observed on WPM containing 1.0 g/L YE. The highest biomass accumulation was observed with treatment of 100 µM CHI. According to the high-performance liquid chromatography results, except for the treatments with 200 µM CHI, 100 or 200 µM MeJA, and 200 µM SA, the remaining elicitor treatments increased stevioside production compared to the control. The production of stevioside increased from 1.56 mg/g dry weight (DW) to 14.69 and 14.54 mg/g DW in the in vitro plantlets exposed to 0.5 g/L ALG and 2.0 g/L YE, respectively. Rebaudioside A was observed on only 0.5 g/L ALG-treated plants as 0.55 mg/g DW. The stevioside content of field-grown plants was identified as 15.06 mg/g DW. The present findings provide important information regarding the effect of elicitors on plant growth and secondary metabolite production of in vitro micropropagated S. rebaudiana.

Molecular structure, vibrational spectroscopic, first-order hyperpolarizability and HOMO, LUMO studies of 3-hydroxy-2-naphthoic acid hydrazide

Abstract: The Fourier-transform infrared spectrum of 3-hydroxy-2-naphthoic acid hydrazide (3H2NAH) was recorded in the region 4000–400 cm−1. The Fourier-transform Raman spectrum of 3H2NAH was also recorded in the region 3500–10 cm−1. Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of 3H2NAH were carried out by density functional theory (DFT/B3LYP) method with 6-31G(d,p) as basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The values of the electric dipole moment (µ) and the first-order hyperpolarizability (β) of the investigated molecule were computed using ab initio quantum mechanical calculations. The UV spectrum was measured in ethanol solution. The calculation results also show that the 3H2NAH molecule might have microscopic nonlinear optical (NLO) behavior with non-zero values. A detailed interpretation of the infrared and Raman spectra of 3H2NAH is also reported based on total energy distribution (TED). The calculated HOMO and LUMO energies shows that charge transfer occur within the molecule. The theoretical FT-IR and FT-Raman spectra for the title molecule have also been constructed. Copyright © 2009 John Wiley & Sons, Ltd.