Publications by authors named "Rekha S Dhar"

Oxidosqualene cyclases (OSCs) positioned at a key metabolic subdividing junction execute indispensable enzymatic cyclization of 2,3-oxidosqualene for varied triterpenoid biosynthesis. Such branch points present favorable gene targets for redirecting metabolic flux toward specific secondary metabolites. However, detailed information regarding the candidate OSCs covering different branches and their regulation is necessary for the desired genetic manipulation.

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Article Synopsis
  • The study focuses on Withania somnifera (ashwagandha), which produces pharmacologically important compounds called withanolides, but lacks detailed insights into their biosynthesis across different growth stages.
  • Researchers collected two variants of the plant at five developmental stages and analyzed the levels of three key withanolides (withanolide-A, withanone, and withaferin A) in leaf and root tissues using high performance liquid chromatography.
  • They also examined the expression of five important biosynthetic genes, finding that withanolide levels were generally higher in leaves compared to roots, indicating potential differences in how these compounds are synthesized in various plant parts.
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Uridine diphosphate glycosyltransferases (UGTs) are pivotal in the process of glycosylation for decorating natural products with sugars. It is one of the versatile mechanisms in determining chemical complexity and diversity for the production of suite of pharmacologically active plant natural products. Picrorhiza kurrooa is a highly reputed medicinal herb known for its hepato-protective properties which are attributed to a novel group of iridoid glycosides known as picrosides.

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Withania somnifera (L.) Dunal, a highly reputed medicinal plant, synthesizes a large array of steroidal lactone triterpenoids called withanolides. Although its chemical profile and pharmacological activities have been studied extensively during the last two decades, limited attempts have been made to decipher the biosynthetic route and identification of key regulatory genes involved in withanolide biosynthesis.

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Withania somnifera is a rich reservoir of pharmaceutically active steroidal lactones known as withanolides. The plant is well characterized in terms of its chemistry and pharmacology, but very little is known about the pathway involved in the biosynthesis of withanolides. The present investigation describes the cloning, characterization and expression of squalene epoxidase (SE) gene from W.

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Withania somnifera (ashwagandha) is a rich repository of large number of pharmacologically active secondary metabolites known as withanolides. Though the plant has been well characterized in terms of phytochemical profiles as well as pharmaceutical activities, but there is sparse information about the genes responsible for biosynthesis of these compounds. In this study, we have cloned and characterized a gene encoding squalene synthase (EC 2.

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The main active components and genetic profile of 15 selected accessions of Withania somnifera Dunal. were analysed. Ethanolic extract of the dried roots/leaves of the plant was concentrated under pressure at 50+/-5 degrees C and was analysed for main compounds (withanolides and withaferin A) by HPLC.

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