Identification of tagitinin C from Tithonia diversifolia as antitrypanosomal compound using bioactivity-guided fractionation

Abstract

Tithonia diversifolia (Asteraceae), is used as traditional medicine in tropical countries for the treatment of various diseases, including malaria. Although numerous studies have assessed the antimalarial properties, nothing is known about the effect of T. diversifolia extracts on trypanosomiasis. In this study extracts of T. diversifolia aerial parts were evaluated for their bioactivity against Trypanosoma brucei. The activity was studied against bloodstream forms of T. brucei (TC221), as well as against mammalian cells (BALB/3T3 mouse fibroblasts), as a counter-screen for toxicity. Both methanolic and aqueous extracts showed significant effects with IC values of 1.1 and 2.2μg/mL against T. brucei (TC221) and 5.2 and 3.7μg/mL against BALB/3T3 cells, respectively. A bioassay-guided fractionation on the methanolic extract yielded in identification of active fractions (F8 and F9) with IC values of 0.41 and 0.43μg/mL, respectively, against T. brucei (TC221) and 1.4 and 1.5μg/mL, respectively, against BALB/3T3 cells,. The phytochemical composition of the extracts and the purified fractions were investigated using HPLC-ESI-MS/MS and 1D and 2D NMR spectra showing the presence of sesquiterpene lactones that in turn were subjected to the isolation procedure. Tagitinin A and C were rather active but the latter presented a very strong inhibition on T. brucei (TC221) with an IC value of 0.0042μg/mL. This activity was 4.5 times better than that of the reference drug suramin. The results of this study shed light on the antitrypanosomal effects of T. diversifolia extracts and highlighted tagitinin C as one of the possible responsible for this effect. Further structure activity relationships studies on tagitinins are needed to consider this sesquiterpenes as lead compounds for the development of new antitrypanosomal drugs.

Comparison of Biostimulant Treatments in Acmella oleracea Cultivation for Alkylamides Production

“…Considering the high abundance of spilanthol in methanol extract of A. oleracea and the need for reference compound for spilanthol, total akylamides quantification was performed by NMR with the use of caffeine as internal standard ( Figure 4 ) using an approach that we previously applied to other plant extracts [ 17 , 18 , 19 ]. Once the amount of spilanthol in commercial extracts was determined, these were then used as reference for the quantification in cultivated samples using the LC approach.…”

“…Preliminary investigation on the possibility to quantify spilanthol by 1 H-NMR were performed using caffeine as internal standard as previously reported for other plant constituents [ 17 , 18 , 19 ]. The extraction was performed weighing 100 mg of dried plant material, adding 1 mg of caffeine, and extracting in methanol in ultrasound bath for 10 min with 25 mL of methanol.…”

Chemical Characterization of Leaves, Male and Female Flowers from Spontaneous Cannabis (Cannabis sativa L.) Growing in Hungary

“…Quantification was achieved using a method previously reported in literature using caffeine as internal standard. [38][39][40]…”

Ethnopharmacological Potential of Tithonia diversifolia (Hemsl) A. Gray

“…Although in recent decades numerous studies have investigated the antimalarial and antileishmanial properties of extracts and molecules isolated from T. diversifolia, the effects of extracts/molecules against trypanosomiasis have not been elucidated (Mota et al, 2014). According to Sut et al (Sut et al, 2018) from the methanolic and aqueous extract of the leaves of T. diversifolia, the anti-trypanosomal (in vitro) action against Trypanosoma brucei was investigated. Initially, the methanolic extract was shown to be more active against the parasite and was chosen for the isolation of the possible metabolites responsible for the pharmacological action, and the Tagitinin A and C were isolated.…”