scholarly journals Characterization of Phenylpropene O-Methyltransferases from Sweet Basil

2002 ◽  
Vol 14 (2) ◽  
pp. 505-519 ◽  
Author(s):  
David R. Gang ◽  
Noa Lavid ◽  
Chloe Zubieta ◽  
Feng Chen ◽  
Till Beuerle ◽  
...  
Keyword(s):  
Author(s):  
Hadush Gebrehiwot ◽  
Aman Dekebo ◽  
Rakesh Kumar Bachheti

<p class="abstract"><strong>Background: </strong>For thousands of years, several people depend on traditional medicines from flowers, bark, leaves and fruits of plants. Sweet Basil (<em>Ocimum basilicum L.</em>) is a medicinal herb which belongs to the family of Labiatae and it is the most abundant of the genus <em>Ocimum.</em> The present study aimed to isolate pure compounds from chloroform/methanol (1:1) crude extract of the leaves of <em>O. basilicum </em>herb and characterize them using infra-red (IR) and nuclear magnetic resonance (NMR) spectroscopic techniques.</p><p class="abstract"><strong>Methods:</strong> The sample of powdered leaves of <em>O. basilicum </em>was extracted using a mixture of chloroform and methanol (1:1) and the crude extract was investigated for its chemical composition using spectroscopic techniques.</p><p class="abstract"><strong>Results:</strong> Only one fraction designated as <em>O. basilicum </em>-14 (OB-14) displayed a single spot on TLC plate. Results showed that two isomeric compounds named <em>(1-(2-vinylcyclohexa-1,4-dienyl) propan-2-ol and 2-(2-vinylcyclohexa-1,5-dienyl) propan-1-ol) </em>were isolated as a mixtures using column chromatography over silica gel. The structures of these compounds were identified using IR and one dimensional NMR spectroscopic techniques such as proton NMR (<sup>1</sup>H NMR), carbon-13 NMR (<sup>13</sup>C NMR) and distortionless enhancement by polarization transfer (DEPT).</p><p class="abstract"><strong>Conclusions:</strong> So, more compounds can be isolated from the plant using different chromatographic techniques.</p>


2003 ◽  
Vol 134 (1) ◽  
pp. 370-379 ◽  
Author(s):  
Yoko Iijima ◽  
David R. Gang ◽  
Eyal Fridman ◽  
Efraim Lewinsohn ◽  
Eran Pichersky

2021 ◽  
Vol 283 ◽  
pp. 110110
Author(s):  
Helale Kaboli Farshchi ◽  
Majid Azizi ◽  
Manouchehr Teymouri ◽  
Amin Reza Nikpoor ◽  
Mahmoud Reza Jaafari

2021 ◽  
Vol 22 (2) ◽  
pp. 681
Author(s):  
Vaishnavi Amarr Reddy ◽  
Chunhong Li ◽  
Kumar Nadimuthu ◽  
Jessica Gambino Tjhang ◽  
In-Cheol Jang ◽  
...  

Production of a volatile phenylpropene; eugenol in sweet basil is mostly associated with peltate glandular trichomes (PGTs) found aerially. Currently only one eugenol synthase (EGS), ObEGS1 which belongs to PIP family is identified from sweet basil PGTs. Reports of the presence of eugenol in roots led us to analyse other EGSs in roots. We screened for all the PIP family reductase transcripts from the RNA-Seq data. In vivo functional characterization of all the genes in E. coli showed their ability to produce eugenol and were termed as ObEGS2-8. Among all, ObEGS1 displayed highest expression in PGTs and ObEGS4 in roots. Further, eugenol was produced only in the roots of soil-grown plants, but not in roots of aseptically-grown plants. Interestingly, eugenol production could be induced in roots of aseptically-grown plants under elicitation suggesting that eugenol production might occur as a result of environmental cues in roots. The presence of ObEGS4 transcript and protein in aseptically-grown plants indicated towards post-translational modifications (PTMs) of ObEGS4. Bioinformatics analysis showed possibility of phosphorylation in ObEGS4 which was further confirmed by in vitro experiment. Our study reveals the presence of multiple eugenol synthases in sweet basil and provides new insights into their diversity and tissue specific regulation.


2020 ◽  
Vol 71 (12) ◽  
pp. 3638-3652 ◽  
Author(s):  
Niha Dhar ◽  
Sreelatha Sarangapani ◽  
Vaishnavi Amarr Reddy ◽  
Nadimuthu Kumar ◽  
Deepa Panicker ◽  
...  

Abstract Sweet basil (Ocimum basilicum) plants produce its characteristic phenylpropene-rich essential oil in specialized structures known as peltate glandular trichomes (PGTs). Eugenol and chavicol are the major phenylpropenes produced by sweet basil varieties whose synthetic pathways are not fully elucidated. Eugenol is derived from coniferyl acetate by a reaction catalysed by eugenol synthase. An acyltransferase is proposed to convert coniferyl alcohol to coniferyl acetate which is the first committed step towards eugenol synthesis. Here, we perform a comparative next-generation transcriptome sequencing of different tissues of sweet basil, namely PGT, leaf, leaf stripped of PGTs (leaf–PGT), and roots, to identify differentially expressed transcripts specific to PGT. From these data, we identified a PGT-enriched BAHD acyltransferase gene ObCAAT1 and functionally characterized it. In vitro coupled reaction of ObCAAT1 with eugenol synthase in the presence of coniferyl alcohol resulted in eugenol production. Analysis of ObCAAT1-RNAi transgenic lines showed decreased levels of eugenol and accumulation of coniferyl alcohol and its derivatives. Coniferyl alcohol acts as a common substrate for phenylpropene and lignin biosynthesis. No differences were found in total lignin content of PGTs and leaves of transgenic lines, indicating that phenylpropene biosynthesis is not coupled to lignification in sweet basil.


Author(s):  
B. L. Soloff ◽  
T. A. Rado

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.


Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.


Author(s):  
B. H. Kear ◽  
J. M. Oblak

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


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