@article { ISI:000294678600026, title = {Biogenic synthesis of silver nanoparticles using nicotiana tobaccum leaf extract and study of their antibacterial effect}, journal = {African Journal of Biotechnology}, volume = {10}, number = {41}, year = {2011}, month = {AUG}, pages = {8122-8130}, publisher = {ACADEMIC JOURNALS}, address = {P O BOX 5170-00200 NAIROBI, VICTORIA ISLAND, LAGOS 73023, NIGERIA}, abstract = {

A green synthesis of silver nanoparticle was carried out using tobacco leaf extract. Synthesized nanoparticles were characterized using UV-Vis absorption spectroscopy, TEM, EDAX, FT-IR and photoluminescence study, respectively. UV-Vis absorption spectroscopy of prepared silver colloidal solution showed absorption maxima at 418 nm. Excitation maximum and emission maximum obtained from photoluminescence study were found at 414 and 576 nm, respectively. TEM analysis showed average particle size of 8 nm, while SAED pattern confirmed the crystalline nature of synthesized nanoparticles. FT-IR analysis indicated the involvement of carboxyl (-C = O), hydroxyl (-OH) and amine (-NH) functional groups of tobacco leaf extract in preparation of silver nanoparticles. EDAX analysis showed proportion of silver (54.55\%) among other elements in nanoparticle. Pseudomonas aeruginosa and Escherichia coli DH5 alpha showed highest sensitivity towards silver nanoparticles.

}, keywords = {FT-IR spectroscopy, photoluminescence, silver nanoparticles, Tobacco, UV-Vis absorption}, issn = {1684-5315}, author = {Prasad, Kumar Suranjit and Pathak, Darshit and Patel, Ankita and Dalwadi, Palak and Prasad, Ram and Patel, Pradip and Selvaraj, Kaliaperumal} } @article { ISI:000302573400003, title = {Cloning, characterization and impact of up- and down-regulating subabul cinnamyl alcohol dehydrogenase (CAD) gene on plant growth and lignin profiles in transgenic tobacco}, journal = {Plant Growth Regulation}, volume = {66}, number = {3}, year = {2012}, month = {APR}, pages = {239-253}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

Both cDNA including 5{\textquoteright}UTR and 3{\textquoteright}UTR and genomic clones of cinnamyl alcohol dehydrogenase (CAD) were isolated and characterized from a pulp-yielding leguminous tree Leucaena leucocephala (LlCAD1). The deduced amino acid sequence shared high identity with orthologous sequences of Acacia mangium x Acacia auriculiformis (83\%), Medicago sativa (83\%), Nicotiana tabaccum (83\%) and Aralia cordata (81\%). Full length cDNA contained 78 bases of 5{\textquoteright}UTR and 283 bases of 3{\textquoteright}UTR, while the genomic clone contained 5 exons and 4 introns. Western blot analysis revealed elevated expression of LlCAD1 in seedling roots and shoots compared to leaves. Sense and antisense CAD tobacco transgenics showed increased and reduced CAD activity accompanied by a change in monomeric lignin composition. Histochemical staining of lignin in down-regulated plants suggested an increase in aldehyde units and a decrease in S/G ratio. Down-regulation of CAD resulted in accumulation of syringic, ferulic, p-coumaric and sinapic acids compared to untransformed controls. These observations were validated by anatomical studies of down-regulated transgenic stems which showed thin walled, elongated phloem and xylem fibres, accompanied by a reduction in the density of vessel elements and amount of secondary xylem when compared to untransformed plants. Furthermore, Klason lignin analysis of CAD antisense transgenics showed 7-32\% reduced lignin and normal phenotype as compared to untransformed plants. Such a reduction was not noticed in up-regulated transgenics. These results demonstrate a unique opportunity to explore the significant role that down-regulation of CAD gene plays in reducing lignin content thereby offering potential benefits to the pulp and paper industry.

}, keywords = {Cinnamyl alcohol dehydrogenase, Lignin down-regulation, Subabul (Leucaena leucocephala), Tobacco}, issn = {0167-6903}, doi = {10.1007/s10725-011-9647-1}, author = {Sirisha, V. L. and Prashant, S. and Kumar, D. Ranadheer and Pramod, S. and Jalaja, N. and Kumari, P. Hima and Rao, P. Maheshwari and Rao, S. Nageswara and Mishra, Preeti and Karumanchi, S. Rao and Khan, Bashir Mohammad and Kishor, P. B. Kavi} } @article {48223, title = {Stacking herbicide detoxification and resistant genes improves glyphosate tolerance and reduces phytotoxicity in tobacco (Nicotiana tabacum L.) and rice (Oryza sativa L.)}, journal = {Plant Physiology and Biochemistry}, volume = {189}, year = {2022}, month = {OCT}, pages = {126-138}, type = {Article}, abstract = {

Glyphosate residues retained in the growing meristematic tissues or in grains of glyphosate-resistant crops affect the plants physiological functions and crop yield. Removing glyphosate residues in the plants is desirable with no penalty on crop yield and quality. We report a new combination of scientific strategy to detoxify glyphosate that reduces the residual levels and improve crop resistance. The glyphosate detoxifying enzymes Aldo-keto reductase (AKR1) and mutated glycine oxidase (mGO) with different modes of action were co-expressed with modified EPSPS, which is insensitive to glyphosate in tobacco (Nicotiana tabacum L.) and rice (Oryza sativa L.). The transgenic tobacco plants expressing individual PsAKR1, mGO, CP4-EPSPS, combinations of PsAKR1:CP4EPSPS, PsAKR1:mGO, and multigene with PsAKR1: mGO: CP4EPSPS genes were developed. The bio-efficacy studies of in-vitro leaf regeneration on different concentrations of glyphosate, seedling bioassay, and spray on transgenic tobacco plants demonstrate that glyphosate detoxification with enhanced resistance. Comparative analysis of the transgenic tobacco plants reveals that double and multigene expressing transgenics had reduced accumulation of shikimic acid, glyphosate, and its primary residue AMPA, and increased levels of sarcosine were observed in all PsAKR1 expressing transgenics. The multigene expressing rice transgenics showed improved glyphosate resis-tance with yield maintenance. In summary, results suggest that stacking genes with two different detoxification mechanisms and insensitive EPSPS is a potential approach for developing glyphosate-resistant plants with less residual content.

}, keywords = {Detoxification, Gene stacking, Glyphosate, Herbicide, Multigene, Residual toxicity, Resistant, rice, Tobacco, Transgenics}, issn = {0981-9428}, doi = {10.1016/j.plaphy.2022.08.025}, author = {Vennapusa, Amaranatha Reddy and Agarwal, Subham and Hm, Hanumanth Rao and Aarthy, Thiagarayaselvam and Babitha, K. C. and Thulasiram, V. Hirekodathakallu and Kulkarni, Mahesh J. and Melmaiee, Kalpalatha and Sudhakar, Chinta and Udayakumar, M. and Vemanna, Ramu S.} }