Effect of Silver Nanoparticles on Production of Indole Alkaloids in Isatis constricta

Abstract

Silver nanoparticles (AgNPs) are widely used in many applications of biotechnology, including medicine and agriculture. They are released to the nature as waste materials, which can cause physiological and biochemical effects on plants. Indigo, indirubin and tryptanthrin are valuable indole alkaloid compounds in Isatis constricta due to both medicinal effects and dye properties. This research was conducted to determine the effects of different concentrations (0, 0.25, 0.5, 1, 1.5 and 2 mg L -1 ) of AgNPs on the production of indigo, indirubin and tryptanthrin compounds in leaves of in vitro grown shoots of I. constricta Davis. Indigo production was 1.15-fold of control (869 ± 8.33 lg g -1 ) in the leaves of shoots regenerated in Murashige and Skoog supplemented with 2 mg L -1 of AgNPs (1003 ± 11.42 lg g -1 ) on 5 days post-treatment. Tryptanthrin production showed an increase in all applications of AgNPs, but the highest increase was observed at a concentration of 2 mg L -1 (4.59 ± 0.046 lg g -1 ) and this increase was 1.71-fold of control (2.68 ± 0.031 lg g -1 ) on 5 days post-treatment. The production of indigo and tryptanthrin decreased on 10 and 15 days post-treatment with AgNPs. The contents of indirubin decreased during day 5-10-15 and at all concentrations of AgNPs compared to the control.

Nanoparticles as Novel Elicitors to Improve Bioactive Compounds in Plants

“…The major aim of inducing bioactive compounds in medicinal plants using NPs is to increase therapeutic activity, which is attributed to its flavonoids, volatile oil, carotenoids, terpenoids, coumarins and alkaloids [84]. Singh et al [65] investigated copper oxide NPs (CuO) elicitation in the culture system; the authors reported an increase of total phenols (27.215 ± 0.73 and 26.455 ± 0.365 mg gallic acid equivalents/g extract) in shoots and roots, flavonoid content (23.076 ± 0.5.128 mg quercetin equivalents/g extract) in roots and antioxidant activity (55.797 ± 1.924 and 56.811 ± 3.012 mg ascorbic acid equivalents/g extract) in shoots and roots in Withania somnifera L. Furthermore, Ag NPs elicitation has been used to improve indigo and tryptanthrin production (1003 µg/g and 4.59 ± 0.006 µg/g respectively) in Isatis treated with a concentration of 2 (mg/L) in plantlets harvested for five days, they exhibited an effect of 1.55 and 1.71 fold of control respectively [71]. Mosavat et al [78] found that different Thymus species and Z. multiflora elicited with ZnO NPs (150 mg/L) in the culture system enhanced thymol and carvacrol content, such as T. kotshyanus and T. daenesis.…”

Alkaloids in Contemporary Drug Discovery to Meet Global Disease Needs

“…Additionally, silver nanoparticles increased the production of tryptanthrin in Isatis constricta P.H. Davis (Brassicaceae) 1.71-fold [223]. Challenges remain, including phytotoxicity and oxidative stress associated with the use of nanoparticles as a treatment for medicinal plants.…”

Boosting of Antioxidants and Alkaloids in Catharanthus roseus Suspension Cultures Using Silver Nanoparticles with Expression of CrMPK3 and STR Genes

“…The potential use of AgNPs to enhance alkaloids biosynthesis was proven in hairy root cultures of Datura metel [53] and Isatis constricta in vitro plants [54]. The increase in alkaloids content in cells without an associated increase in growth medium recorded in our results at 10 mg L −1 may reflect intracellular sinks for the newly synthesized alkaloids to cope the oxidative stress before immobilization to growth medium or suggest the ability of cells to retain alkaloids within intracellular specialized structures avoiding cytotoxicity with high concentrations in the growth medium [55].…”