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Item Importance of Dietary Supplements to the Health(Bentham Science, 2021) Shrivastava, RichaThe term “dietary supplement” defines a comprehensive and diverse category of products that are essential to our health but are absent or insufficient in the diet and may be needed to take separately; requirement of dietary supplements varies at different stages of life, such as infant, child-adult, pregnancy, lactation, and geriatrics. Dietary supplements are not medicines, nor should they be considered a substitute for food. The USFDA defines dietary supplements in part as a product taken by mouth that contains “dietary ingredients.” Nutritional ingredients comprise vitamins, minerals, amino acids, and herbs or botanicals, in addition to other substances that can be considered to supplement the diet. The market is flooded with various dosage forms of dietary supplements, such as capsules, tablets, powders, energy bars, liquids, etc. These include vitamins, minerals, herbal products containing extracts from herbs as well as algae and fungi, concentrate, metabolite, constituent, or extract, enzyme supplements, essential amino, and fatty acids. This article describes the importance of the dietary supplement, its source, diseases that arise from deficiency, and the recommended doses for different groups.Item Copper-catalysed Csingle bondN/Csingle bondO coupling in water: a facile access to N-coumaryl amino acids and fluorescent tyrosine & lysine labels(Elsiever, 2016-06) Bajaj, Kiran; Sakhuja, RajeevA mild, efficient, ligand free and environmentally benign approach towards the construction of sp2 C-sp3 N bond has been developed via copper catalysed Ullmann type of coupling between 4-chlorocoumarin with N-terminus unprotected amino acids in microwave-aqua conditions, yielding a series of N-coumaryl amino acids in good to excellent yields. Excellent photo-physical properties exhibited by these N-coumaryl amino acids and their chemical applicability as C-terminus coupling partners for N-terminus peptides make them potential fluorescent probes in labelling studies. The methodology was extended towards the Csingle bondO and Csingle bondN coupling for the synthesis of fluorescent coumaryl labelled tyrosine and lysine labels respectively. Application of coumaryl labelled tyrosine was further explored towards the synthesis of fluorescent labelled opioid tetrapeptide, Endomorphin-2 derivative.Item Efficient Syntheses of Naphthoquinone-Dipeptides(Thieme, 2010) Sakhuja, RajeevNaphthoquinone-dipeptides are synthesized in 76-89% yield from naphthoquinone-amino acid conjugates by N-acylbenzotriazole methodology in aqueous media at 20 ˚CItem Copper-catalysed Csingle bondN/Csingle bondO coupling in water: a facile access to N-coumaryl amino acids and fluorescent tyrosine & lysine labels(Elsiever, 2016-06-22) Sakhuja, Rajeev; Bajaj, KiranA mild, efficient, ligand free and environmentally benign approach towards the construction of sp2 C-sp3 N bond has been developed via copper catalysed Ullmann type of coupling between 4-chlorocoumarin with N-terminus unprotected amino acids in microwave-aqua conditions, yielding a series of N-coumaryl amino acids in good to excellent yields. Excellent photo-physical properties exhibited by these N-coumaryl amino acids and their chemical applicability as C-terminus coupling partners for N-terminus peptides make them potential fluorescent probes in labelling studies. The methodology was extended towards the Csingle bondO and Csingle bondN coupling for the synthesis of fluorescent coumaryl labelled tyrosine and lysine labels respectively. Application of coumaryl labelled tyrosine was further explored towards the synthesis of fluorescent labelled opioid tetrapeptide, Endomorphin-2 derivative.Item Amino acid appended cholic acid–azobenzene dyad: an effective & smart phase selective gelator for aromatic solvents(RSC, 2016) Sakhuja, RajeevA series of amino acid appended cholic acid–azobenzene dyads have been synthesized and studied for their gelation behaviour. One of the L-alanine based dyads showed excellent gelation behaviour in a variety of solvents at room temperature with minimum gel concentration in the range 0.8% (w/v)–1.8% (w/v). The morphology of the stable gels indicated the formation of a lamellar or a dense sheet network in different solvents. Variable temperature 1H-NMR and FT-IR studies revealed an evident role of intermolecular hydrogen bonding in the self-assembly process. The photo-isomerization between the trans and cis forms of the azobenzene unit was established by UV-visible spectroscopy, and a comparison of 1H NMR and SEM images of the gel and sol forms. In addition, π → π stacking between phenyl groups of azobenzene might have provided an additional driving force for the formation of a dense three-dimensional network capable of phase selective gelation of aromatic solvents from a water/solvent mixture. This selective gelation of aromatic solvents remains unaffected even in the presence of the common salts usually present in water from different sources. The phase selective gelation ability of the dyad was successfully explored towards the removal of toxic fat-soluble rhodamine dye from water and selectively gelatinizing petrol and crude oil from an oil/water mixture at room temperature. Thus, these smart systems possess the potential to be used effectively in water purification and oil-spill remediation.Item Defining the current scope and limitations of dual noncanonical amino acid mutagenesis in mammalian cells(RSC, 2017) Addy, Partha SarathiThe ability to site-specifically incorporate two distinct noncanonical amino acids (ncAAs) into the proteome of a mammalian cell with high fidelity and efficiency will have many enabling applications. It would require the use of two different engineered aminoacyl-tRNA synthetase (aaRS)/tRNA pairs, each suppressing a distinct nonsense codon, and which cross-react neither with each other, nor with their counterparts from the host cell. Three different aaRS/tRNA pairs have been developed so far to expand the genetic code of mammalian cells, which can be potentially combined in three unique ways to drive site-specific incorporation of two distinct ncAAs. To explore the suitability of using these combinations for suppressing two distinct nonsense codons with high fidelity and efficiency, here we systematically investigate: (1) how efficiently the three available aaRS/tRNA pairs suppress the three different nonsense codons, (2) preexisting cross-reactivities among these pairs that would compromise their simultaneous use, and (3) whether different nonsense-suppressor tRNAs exhibit unwanted suppression of non-cognate stop codons in mammalian cells. From these comprehensive analyses, two unique combinations of aaRS/tRNA pairs emerged as being suitable for high-fidelity dual nonsense suppression. We developed expression systems to validate the use of both combinations for the site-specific incorporation of two different ncAAs into proteins expressed in mammalian cells. Our work lays the foundation for developing powerful applications of dual-ncAA incorporation technology in mammalian cells, and highlights aspects of this nascent technology that need to be addressed to realize its full potential.Item Functionalization of Single-Walled Carbon Nanotubes with Azides Derived from Amino Acids Using Click Chemistry(Ingenta, 2008-07) Kumar, IndreshSingle-walled carbon nanotubes (SWCNTs) were chemically functionalized with amino acid-based moieties. The covalent functionalization of alkyne-derived SWCNTs with well defined azides derived from amino acids was accomplished through Cu(I)-catalyzed Huisgen [3 + 2] dipolar cycloaddition click chemistry. Transmission electron microscopy, Raman spectroscopy, and infrared spectroscopic measurements confirmed the functionalization of SWCNTs by organic molecules derived from amino acids, and the resulting material showed some good solubility in the organic solvents such as tetrahydrofuran, CH2Cl2, and CHCl3.Item Coordination behavior of biologically active schiff bases of amino acids towards silicon(IV) ion(Taylor & Francis, 2006-10) Khungar, BhartiReactions of diethoxydimethylsilane with Schiff bases derived from the condensation of fur-furaldehyde. indole-3-carbaldehyde with alanine, glycine, valine, isoleucine and tryptophan in a 1:2 molar ratio give a new series of Me2Si (NO)2 type of organosilicon (IV) complexes. The complexes are monomeric and non-electrolytic in nature. The coordination behaviour of Schiff babes through organosilicon (IV) has been investigated by IR, 1H, 13C & 29Si NMR spectral studies. Schiff bases and their silicon complexes have also been screened for their antifungal activity. Several of these complexes were found to be quite active in this respect.Item The synthesis of amino acid derived glycoconjugates and the investigation of their anti-inflammatory and analgesic properties(2014) Sah, Ajay KumarA series of 4,6-O-ethylidene-β-D-glucopyranosylamine derived glycoconjugates containing amino- and aromatic acids have been synthesized. All these molecules have been tested for their anti-inflammatory and analgesic activity on Wistar rat and Swiss Albino mice respectively. The anti-inflammatory studies were explored using a carrageenan induced paw oedema model while an acetic acid induced writhing model was adapted for the analgesic studies. All of the compounds exhibited anti-inflammatory and analgesic activity in the range of 63–84% and 86–94% respectively.Item N-Glycoconjugates: Selective colorimetric chemosensors for aspartic acid and cysteine(Elsiever, 2021-10-05) Sah, Ajay KumarSelective recognition of naturally occurring amino acids have been explored using five glycopeptide-based receptors with the help of UV-visible and 1H NMR spectroscopy, while structures of two glycopeptides have been established via single crystal X-ray diffraction studies. The receptors containing alanine, valine, isoleucine and methionine moieties interact selectively with aspartic acid, while phenylalanine derivative with cysteine.