Withania somnifera

About: Withania somnifera is a research topic. Over the lifetime, 2116 publications have been published within this topic receiving 43404 citations. The topic is also known as: Ashwaganda & Indian ginseng.

Molecular characterization of three CYP450 genes reveals their role in withanolides formation and defense in Withania somnifera, the Indian Ginseng

Abstract: The medicinal properties of Ashwagandha (Withania somnifera) are attributed to triterpenoid steroidal lactones, withanolides, which are proposed to be derived from phytosterol pathway, through the action of cytochrome P450 (CYP450) enzymes. Here, we report the characterization of three transcriptome-mined CYP450 genes (WsCYP749B1, WsCYP76 and WsCYP71B10), which exhibited induced expression in response to methyl jasmonate treatment indicating their role in secondary metabolism. All three WsCYP450s had the highest expression in leaf compared to other tissues. In planta characterization of WsCYP450s through virus induced gene silencing (VIGS) and transient overexpression approaches and subsequent metabolite analysis indicated differential modulation in the accumulation of certain withanolides in W. somnifera leaves. While WsCYP749B1-vigs significantly enhanced withaferin A (~ 450%) and reduced withanolide A (~ 50%), its overexpression drastically led to enhanced withanolide A (> 250%) and withanolide B (> 200%) levels and reduced 12-deoxywithastramonolide (~ 60%). Whereas WsCYP76-vigs led to reduced withanolide A (~ 60%) and its overexpression increased withanolide A (~ 150%) and reduced 12-deoxywithastramonolide (~ 60%). Silencing and overexpression of WsCYP71B10 resulted in significant reduction of withanolide B (~ 50%) and withanolide A (~ 60%), respectively. Further, while VIGS of WsCYP450s negatively affected the expression of pathogenesis-related (PR) genes and compromised tolerance to bacteria P. syringae DC3000, their overexpression in W. somnifera and transgenic tobacco led to improved tolerance to the bacteria. Overall, these results showed that the identified WsCYP450s have a role in one or several steps of withanolides biosynthetic pathway and are involved in conferring tolerance to biotic stress.

Biochemical study of root extract of Withania somnifera (L.) plant through HPLC analysis

Abstract: Secondary metabolite contents of W. somnifera varied remarkably between seasons and genotypes under ex vitro condition. In vitro studies provide an optimum culture condition for steady and quality production of bioactive chemicals throughout the year without involvement of environmental stresses. Mass production of micro-shoots and plantlets by exploring the organogenic totipotency of shoot tip explants (ex vitro and in vitro grown) considering two elite genotypes (Poshita and Jawahar 22) of W. somnifera, and assessment of their capability in production and accumulation of bioactive metabolites (total alkaloid and withanolides amount were quantified; withanolide A and withaferin A contents were estimated by High Performance Liquid Chromatography-HPLC).

Adjuvant composition for vaccine

Abstract: The present invention provides a Withania somnifera fraction rich in withanolides and a vaccine comprising a “ Withania somnifera fraction” as an adjuvant.

Inhibition of Acetylcholinesterase and NO Synthase Activity in the Mice Brain: Effect of a Withania Somnifera Leaf Juice

Abstract: Inhibitory effects of a fresh leaf juice of the Withania somnifera (W.s.) on the enzymes acetylcholinesterase (AChE; EC 3.1.17) and nicotinamide adenine dinucleotide diaphorase (NADPH-d) were studied in the mice brain using histochemical and biochemical approaches. The results obtained show significant reduction in the number of and reaction intensity in AChE- and NADPH-d-positive neurons within selected areas of the brains of W.s.-treated mice. Colocalization of AChE and NADPH-d activity also showed significant reduction in the number of cells positive for both enzymes after W.s. treatment, as compared to cells with isolated localization of AChE or NADPH-d. Biochemical estimation of the AChE and NADPH-d levels in brain tissue also showed significant dose-dependent inhibition of the activity of both enzymes after W.s. treatment. In conclusion, our study allows us to suggest that W.s. constituents significantly inhibit both AChE and NADPH-d activity. Inhibition of AChE is direct, while NADPH-d is inhibited indirectly. This study might be important for possible therapeutic use of W.s. in neurodegenerative disorders, in particular in Alzheimer’s disease where inhibition of both AChE and nNOS is important.