Alkaloid composition and antimicrobial activity of Chelidonium majus L. from natural habitats and in vitro cultures

 

Chelidonium majus L (Greater celandine) – is an ancient and popular European folk medicinal herb. It grows spontaneously in rich synanthropic habitats and is also cultivated for needs of herbal industry. Major pharmacologically relevant components of Ch. majus are several isoquinoline alkaloids: chelidonine, chelerythrine, sanguinarine, berberine, and coptisine. The compounds are stored and secreted from laticifers – highly specialized elongated cells. However, we also observed a characteristic orange-yellow color of latex in dedifferentiated tissue culture. RP-DAD-HPLC analysis of Ch. majus extracts obtained from roots, immature fruits, and leaves showed differences in the quality and quantity of all analyzed alkaloids. Aerial parts (leaves and immature fruits contained lesser amounts of alkaloids (averaging at 15 mg/g dw) and the major of them were chelidonine in leaves and coptisine along with chelidonine in fruits. In roots, sanguinarine was the predominating compound followed by chelidonine and chelerythrine and the alkaloid content (sum of 7 compounds) reached 40 mg/g.

To assess antimicrobial activity, we used standard microdilution method according to EUCAST guidelines. In case of Gram-positive pathogens, i.e. Staphylococcus aureus and Enterococcus faecalis, MIC of MeOH extracts was 62.5 mg/L and also a strong reduction of bacterial biomass in comparison to untreated bacteria was observed when 31.25 mg/L of extract was used – 49% and 68% for S.aureus and E.faecalis, respectively. All extracts also inhibited Candida growth by 70 to 80%, depending on the fungal strain. For example, leaf MeOH extract treated C. glabrata cells were reduced by 73% at the concentration of only 10 mg/L. At 60 mg/L, the leaf extract reduced 80% of biomass of C. parapsilosis and C. krusei. Ch. majus extracts might therefore find an application in eradication of Gram-positive cocci, but are especially promising against Candida pathogenic strains other than C. albicans, including those with significant resistance against standard antimycotic drugs.