Cadmium chloride (CdCl2) elicitation improves reserpine and ajmalicine yield in Rauvolfia serpentina as revealed by high-performance thin-layer chromatography (HPTLC)

Abstract

In vitro cultures play a promising role for production of pharmaceutically important plant secondary metabolites and the use of elicitation can mitigate the low productivity of active compounds. In the present study, the influence of cadmium chloride (CdCl 2 ) elicitation on alkaloid yield was investigated in Rauvolfia serpentina. This heavy metal was employed to enhance the yield of reserpine and ajmalicine in leaf derived callus, leaves, stems and roots of in vitro grown cultures. Different concentrations [0.05 mM (C1), 0.10 mM (C2), 0.15 mM (C3) and 0.20 mM (C4)] of CdCl 2 were added to the MS medium. The elicitor's influence on callus biomass, biochemical attributes and the yield of alkaloids was monitored at regular intervals. The amendment of CdCl 2 improved growth and maximum callus biomass (1.29 g fresh weight and 0.16 g dry weight) was noted at 0.15 mM (C3) after 6 days of elicitation. The addition of elicitor in medium caused cellular stress and to analyse the role of CdCl 2 in plant defence responses various antioxidant enzymes, i.e., superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activities were measured in treated and non-treated cultures. The antioxidant enzyme activity increased linearly with elevated levels of CdCl 2 in medium; highest APX (0.88 EU min −1 mg −1 protein), SOD (5.40 EU min −1 mg −1 protein) and CAT (4.21 EU min −1 mg −1 protein) activity were observed in leaves of in vitro regenerated plants at C4. The quantitative analyses of reserpine and ajmalicine were conducted in different elicitated tissues using high-performance thin-layer chromatography (HPTLC) method. The study reveals enriched level of reserpine and ajmalicine in cultivated tissues and the enhancement was noted up to C3 (0.15 mM) elicitor level. Reserpine yield was maximum (0.191 mg g −1 DW) in roots of in vitro regenerated plants. The accumulation of ajmalicine was, however, better in leaf derived callus at C3 (0.131 mg g −1 DW). Higher elicitor dose (0.20 mM) inhibited callus biomass growth and subsequent alkaloid accumulation. The present study indicates the use of CdCl 2 as a propitious method in enhancing reserpine and ajmalicine yield in R. serpentina.

The Antioxidant, Cytotoxic and Antimicrobial Potential of Phenolic Acids-Enriched Extract of Elicited Hairy Roots of Salvia bulleyana

“…Elicitors are stress factors that play an important role in adaptation to stressful conditions by triggering various defense responses in plants, including the production and accumulation of secondary metabolites. This has been earlier reported for different phytochemicals known for their pharmacological activity, such as alkaloids, cardenolides, terpenoids and phenols [ 15 , 16 , 17 ].…”

Stymulujący wpływ metali na biosyntezę roślinnych związków chemicznych o bioaktywnym działaniu.

“…Jedną z takich metod jest hodowla roślin o leczniczych właściwościach w kulturach in vitro. Ten sposób hodowli roślin zastosowano między innymi przy badaniach wpływu metali na poziom metabolitów wtórnych w rauwolfii żmijowej (Rauvolfia serpentina), fagonii indyjskiej (Fagonia indica) i czosnku pospolitym (Allium sativum) [27][28][29]. Rauwolfia żmijowa była wykorzystywana już w ajurwedzie, tradycyjnej medycynie hinduskiej liczącej ponad 2500 lat.…”

“…Jej uspakajające i hipotensyjne (obniżające ciśnienie) działanie zostało potwierdzone przez badania naukowe. W 1952 roku wyizolowano jeden z głównych składników bioaktywnych syntetyzowanych przez rauwolfięrezerpinę, która znalazła zastosowanie w lekach na nadciśnienie [27,30]. Badania prowadzone w kulturach in vitro rauwolfii żmijowej wykazały, że Cd w znaczny sposób zwiększał biosyntezę rezerpiny.…”

Influence of plant growth regulators on morphogenic response, biomass and camptothecin production in the callus cultures of Chonemorpha fragrans (moon) Alston

“…CPT evaluation and statistical analysis Extraction of CPT from dried callus cultures of C. fragrans and culture medium, and high-performance thin layer chromatographic (HPTLC) analysis of the extracts were carried out as described in the recent (Isah, 2019;Isah and Umar, 2019), modified in Zafar et al (2020) and Mujib et al (2020). CPT yield of the tissues and culture medium were evaluated using standard curve that had a linear regression line equation and expressed in percentages for tissues used without organogenesis study and in mg/g calli DW or mg/mL medium for others obtained from organogenesis study (experiments carried out at different times).…”