Differential alkaloid profile in Uncaria tomentosa micropropagated plantlets and root cultures

Abstract

The alkaloids of Uncaria tomentosa micropropagated plantlets and root cultures were isolated and identified by NMR and mass spectrometry. Plantlets yielded pteropodine (1), isopteropodine (2), mitraphylline (3), isomitraphylline (4), uncarine F (5), speciophylline (6), rhynchophylline (7) and isorhynchophylline (8). In plantlets growing under continuous light, tetracyclic alkaloids 7 and 8 decreased from 20 ± 1.8 at 2 months to 2.2 ± 0.33 mg/g dry wt at 6 months, while the pentacyclic alkaloids 1-4 increased from 7.7 ± 1.4 to 15 ± 0.05 mg/g dry wt, supporting their biogenetic conversion. Micropropagated plantlets produced four times more alkaloids (27.6 ± 3.1 mg/g dry wt) than greenhouse plants. Plantlet roots yielded 3, 4, 8 and the glucoindole alkaloids 3α-dihydrocadambine (9) and dolichantoside (10), the last one not previously found in Uncaria.

Uncaria tomentosa and Uncaria guianensis an agronomic history to be written

“…The content of tetracyclic alkaloids is higher in younger seedlings, whereas the pentacyclic alkaloids accumulate more in older plants (LUNA-PALENCIA et al, 2013).…”

“…In this context, various descriptions of in vitro insertion of U. tomentosa are available. However, a micropropagation protocol showing the production viability on a commercial scale, e.g., using a temporary immersion system was not yet published (FERIA-ROMERO et al, 2005;PEREIRA et al, 2006;LUNA-PALENCIA et al, 2013).…”

“…They are divided into indole tetracyclic alkaloids (corynanthein, dihydrocorynanthein, hirsuthein, and hirsutine) oxindole alkaloids (rhynchophylline, isorhynchophylline, corynoxein, isocorynoxein, rotundifolin, and isorotundifolin) indole pentacyclic alkaloids (akuamigine, augustine, augustolin, isoamalicin, and tetrahydroalstonin) and oxindole alkaloids (speciophylline, mitraphylline, isomitraphylline, pteropodin, isopteropodin, and uncarin F), and glycoindole alkaloids (3α-dihydrocadambine and dolichantosin) (LAUS et al, 1997;FALKIEWICZ & LUKASIAK, 2001;LUNA-PALENCIA et al, 2013). Besides the alkaloids, the triterpenic heterosides (derived from the quinovic acid) and polyphenols (especially tannin) are also highlighted (PAVEI et al, 2012;SHENG et al, 2005).…”

Monoterpenoid indole alkaloids and phenols are required antioxidants in glutathione depleted Uncaria tomentosa root cultures

“…Root cultures of U. tomentosa (line Utr-3) arising from micropropagated plantlets (Luna-Palencia et al, 2013) were grown in 250-mL Erlenmeyer flasks (covered with aluminum foil) with 100-mL of MS medium (Murashige and Skoog, 1962), 2% sucrose without plant growth regulators and pH 6.4 adjusted prior to sterilization. The cultures were incubated at 25 ± 2 • C, using orbital agitation at 110 rpm, and under continuous light intensity 13 µmol m −2 s −1 .…”

“…This plant produces the highly oxidized monoterpenoid oxindole alkaloids (MOA) isopteropodine, mitraphylline, isomitraphylline and rhynchophylline, which exhibits immunomodulatory, anti-AIDS, cytotoxic, and antileukemic properties (Laus, 2004). In previous work, it was found that root suspension cultures of this species produced MOA and accumulated 3α-dihydrocadambine (Huerta-Heredia et al, 2009), a glucoindole alkaloid with hypotensive and antioxidant activities (Endo et al, 1983) and dolichantoside (Luna-Palencia et al, 2013), a N-β-methylated strictosidine with potent anti-malarial effect (Frédérich et al, 2000). Moreover, the antioxidant response and alkaloid production stimulation have been correlated with oxidative stress (Trejo-Tapia et al, 2007) triggered by H 2 O 2 treatment (HuertaHeredia et al, 2009;Vera-Reyes et al, 2013) and by combined addition of the glutathione inhibitor, buthionine sulfoximine and jasmonic acid (Vera-Reyes et al, 2013).…”