Content of pyrrolizidine alkaloids in the leaves of coltsfoot (Tussilago farfara L.) in Poland

Abstract

Coltsfoot (<em>Tussilago farfara</em> L.) is a common species, widely used in European and Chinese traditional medicine for the treatment of respiratory diseases. However, raw material from this plant contains hepatotoxic pyrrolizidine alkaloids (PAs). The aim of the study was to determine the variability of the level of PAs (senkirkine and senecionine) in leaves of coltsfoot originated from natural populations in Poland. In the phytochemical analysis, 20 samples of <em>T. farfara</em> were used. This plant material was obtained from the Garden of Medicinal Plants in Plewiska near Poznań and originated from different regions of Poland. Coltsfoot leaves were harvested in the middle of July of 2010 and then dried at room temperature. The alkaloid content was detected using the HPLC-DAD method. The amount of PAs in leaves of <em>T. farfara</em> changed in a wide range from 0.06 to 1.04 μg g<sup>−1</sup> of dry matter (DM). The content of senkirkine and senecionine was positively correlated (<em>r</em> = 0.68, <em>P</em> = 0.001). There was no statistically significant correlation between the amount of PAs as well as leaf weight and water content in leaves of <em>T. farfara</em>. Our results showed that a medium-sized leaf of coltsfoot (0.33 g DM) may contain from 0.02 to 0.34 μg of PAs (on average 0.14 μg). The level of PAs was not associated with the region of Poland, but phytochemical similarity of samples was usually visible at the local scale. Coltsfoot leaves are characterized by a high variability of the content of toxic PAs, much higher than in the case of the main active compounds, especially flavonoids and mucilage.<br /> This phytochemical variability is mainly genetically determined (samples came from a garden collection), and it can be increased by environmental factors. Our investigations indicate that Polish natural populations of <em>T. farfara</em> may provide raw material with a low level of toxic PAs.

Pyrrolizidine Alkaloids: Chemistry, Pharmacology, Toxicology and Food Safety

“…Due to the presence of PA in several species relevant for human and animal nutrition, they may pose a threat to human health through their presence in herbal teas, herbal medicines, dietary supplements, vegetables, cereals, wheat grain, honey and pollen [ 93 , 94 , 95 , 96 , 97 , 98 ]. Cases of intoxication by contaminated cereals, teas, and salads have been extensively reported [ 97 , 99 , 100 ].…”

A review of the ethnobotanical value, phytochemistry, pharmacology, toxicity and quality control of Tussilago farfara L. (coltsfoot)

“…In Norway, the dried and cut leaves of coltsfoot, as folk medicines, are sold and used in teas for the relief of coughs and chest complaints ( Xue et al , 2012 ). In Europe, the leaves are used to treat bronchial infections while in China the flower buds are preferred ( Adamczak et al , 2013 ). Moreover, in traditional Chinese medicines (TCMs), the flower bud of coltsfoot is often used the form of processed honey-fry, which showed a detoxifying effect.…”

“…Some of them have been deemed to possess biological activities, and this is notably the case with TSL ( 13 ). Most notably, the concentration of PAs in coltsfoot varies widely ( Adamczak et al , 2013 ) and cultivation of a PAs-free variety is being developed in Austria, ( Wawrosch et al , 2000 ). Moreover, Pfeiffer et al (2008) highlights the correlation of vegetative multiplication in coltsfoot, as an important pioneer species, which has been achieved rapidly via repeated clonal growth and subsequent clonal reproduction ( Pfeiffer et al , 2008 ).…”

Pyrrolizidine alkaloids inTussilago farfarafrom Bulgaria

“…However, the data are widely ranging from 0 to 368 mg/g. [33,36] For 20 natural populations from Poland, Adamczak et al [33] reported (senkirkine and senecionine) content in the range of 0.06À1.04 mg/g. According to these data, PAs, found in the studied Bulgarian population of T. farfara, were close to the lower range limit and could be perceived as population with low alkaloid content.…”

“…Factors that affect the accumulation of alkaloids are still under discussion, but it is outlined that variability of PAs is mainly genetically determined and it can be increased by environmental factors. [33] The presence of the double bond is an important determinant in the hepatotoxicity of PAs, because only those with 1,2-unsaturation are hepatotoxic. The toxicity of PAs is due to metabolic activation.…”