Methyl‐β‐cyclodextrin and coronatine as new elicitors of tropane alkaloid biosynthesis in Atropa acuminata and Atropa belladonna hairy root cultures

Abstract

Hyoscyamine (HYO) and scopolamine (SCO) are tropane alkaloids acting as anticholinergic factors on the parasympathetic nervous system in humans and are produced by Solanaceous plants. Two strains of Agrobacterium rhizogenes, A4 and LBA9402, were used to infect Atropa acuminata Royle ex Miers and Atropa belladonna L. leaf explants. A. acuminata was inoculated either by direct infection or sonicated-assisted A. rhizogenes-mediated transformation (SAAT) was performed. A. belladonna was inoculated with the A4 strain using a direct method. The selected hairy root lines of both species were elicited with 50 mM methyl-β-cyclodextrin (β-CD), 0.5 μM coronatine (Cor) or 50 mM β-CD + 0.5 μM Cor on Day 14 of culture. The elicitor effect on growth and HYO and SCO content was analyzed after one (T1) and two (T2) weeks of treatment. In A. acuminata explants, the highest transformation percentage (T%) was obtained with strain A4 and the SAAT method (T%: 96.43). Cor significantly reduced the growth of A. acuminata hairy roots (fresh weight and dry weight [DW]: 2.52 and 0.3 g, respectively), whereas β-CD increased their DW (0.4 g). Also, the combined β-CD + Cor treatment had a positive significant effect on the DW of A. belladonna hairy roots (0.41 g). In A. acuminata hairy roots, the HYO level was lower under Cor treatment than in the control at both sampling times. In contrast, the SCO content was increased 10-fold by Cor elicitation at T1 compared to the control (10.95 mg g À1 DW) and was also positively affected by β-CD + Cor. In A. belladonna hairy roots, all the elicitors had a negative effect on both HYO and SCO production. This report is the first assessment of the effect of β-CD and Cor elicitors on tropane alkaloid production. 1 | INTRODUCTION Hyoscyamine (HYO) and scopolamine (SCO) are the most pharmacologically important tropane alkaloids, acting as anticholinergic factors on the parasympathetic nervous system in humans. These anticholinergic agents have extensive applications in medicine. They are used as anesthetics, antispasmodics, mydriatics, preoperative medication, sedatives, narcotics and in the treatment of asthma, cardiac and gastrointestinal disorders, Parkinson's disease and motion sickness

Metabolic Effects of Elicitors on the Biosynthesis of Tropane Alkaloids in Medicinal Plants

“…production and hyoscyamine release. However, the same treatment negatively affected both hyoscyamine and scopolamine production from Atropa belladonna hairy roots [113].…”

“…Co-treatment of Atropa acuminata hairy roots with 50 mM methyl-β-cyclodextrin (β-CD) and 0.5 uM of COR was found to positively affect both scopolamine production and hyoscyamine release. However, the same treatment negatively affected both hyoscyamine and scopolamine production from Atropa belladonna hairy roots [113].…”

Hairy root culture: a potent method for improved secondary metabolite production of Solanaceous plants

“…Even so, the production levels can be further improved by the application of elicitors in the hairy root culture systems. Several studies have shown that enhanced production of different classes of metabolites can be achieved in hairy root cultures of solanaceous plants of Anisodus acutangulus , Atropa acuminata , A. baetica , A. belladonna , Brugmansia candida , Datura metel , D. stramonium , Hyoscyamus albus , H. muticus , H. reticulatus , Solanum mammosum , S. myriacanthum , S. trilobatum , and Withania somnifera , upon elicitation ( Mehmetoğlu and Curtis, 1997 ; Kuroyanagi et al., 1998 ; Pitta-Alvarez and Giulietti, 1998 ; Jacob and Malpathak, 2005a ; Jacob and Malpathak, 2005b ; El Jaber-Vazdekis et al., 2008 ; Doma et al., 2012 ; Kai et al., 2012a ; Shilpha et al., 2015 ; Ooi et al., 2016 ; Srivastava et al., 2016 ; Moharrami et al., 2017 ; Shakeran et al., 2017 ; Amdoun et al., 2018 ; Moradi et al., 2020 ; Fattahi et al., 2021 ) ( Supplementary Table 1 ).…”

Bacteria – Plant Interaction: Transgenic Roots for Human Health

“…The expression of several genes (PAL, CCR, CAD, and PLR) was also enhanced. Fattahi et al (2021) explored the effect of methyl-β-cyclodextrins and coronatine (individually and combined) on tropane alkaloids accumulation in Atropa acuminata and A. belladonna hairy roots. In A. belladonna all the treatments reduced alkaloid production, while in A. acuminata, coronatine elicitation increased the scopolamine content 10-fold compared to the control (10.95 mg/g DW).…”