Biological activities of meadowsweet (Filipendula ulmaria (L.) Maxim)

Filipendula ulmaria (L.) Maxim (meadowsweet) is a medicinal plant that has been used to treat several inflammatory diseases including gout and rheumatoid arthritis, and for the treatment of coughs, bronchitis, fevers, ulcers and colds. Three different bioassays (antibacterial, antitumor and toxicity) were performed to show the biological activities of meadowsweet. They were evaluated between field-grown plants and in vitro-grown plants using eight different extracts (aqueous, ethanol, ethylacetate and hexane). The disc diffusion assay (Kirby-Bauer Method) was used to screen for antibacterial activity [1]. The microorganisms used were: Streptococcus pyogenes (ATCC® 19615), Staphylococcus aureus (ATCC® 25923) and Staphylococcus epidermidis (ATCC® 12228) which are Gram-positive bacteria and Escherichia coli (ATCC® 25922), Pseudomonas aeruginosa (ATCC® 27853), Salmonella typhimurium (ATCC® 14028), Serratia marcescens (ATCC® 8100), Proteus vulgaris (ATCC® 13315), Enterobacter cloacae (ATCC® 23355) and Klebsiella pneumoniae (ATCC® 13883) which are Gram-negative bacteria. Generally, antibacterial activities of field-grown plants were better than in-vitro grown plants against all used bacteria. Aqueous extract of field-grown plant (FW) exhibited better antibacterial activity than other extracts. S.epidermidis, S. aureus, S. typhimurium, S. marcescens, P. aeruginosa, P. vulgaris, K. pneumonia and E. cloacae were sensitive to FW. Antitumor activity of all extracts was assessed with the potato disc method as modified by McLaughlin's group [2].The inhibition of Agrobacterium tumefaciens-induced tumors (or crown gall) in potato disc tissue is an assay based on antimitotic activity and can detect a broad range of known and novel antitumor effects [3,4]. The validity of this bioassay is predicted on the observation that certain tumorigenic mechanisms are similar in plants and animals. It has been shown that the inhibition of crown gall tumor initiation on potato discs and subsequent growth showed good correlation with compounds and extracts active in the 3PS (P388) (in vivo murine leukemia) leukemic mouse assay [4,5]. Field-grown plants showed better activity than in vitro-grown plants. But, after viability test for A. tumefaciens, it was understood that inhibition of crown gall formation on potato disc is caused by decreasing the viability of the A. tumefaciens. It is not possible to evaluate the antitumor activity of F. ulmaria with potato disc bioassay. Because meadowsweet extracts have very strong antibacterial activity and affect the viability of A. tumefaciens. The brine shrimp bioassay was used to assess the general toxicity of meadowsweet extracts [6]. All extracts were toxic at higher doses (LC₅₀>2.000mg/l) by comparing with MS-222 (Tricaine methane sulfonate). Aqueous extracts of field-grown and in vitro-grown plants were less toxic than other extracts (ethanol, ethylacetate and hexane).

References: [1] Andrews, J.M. (2004)J. Antimicrob. Chemoth. 53:713–728.

[2] Ferrigini, N.R. et al. (1982)J. Nat. Prod. 45:679–686.

[3] McLaughlin, J.L., Rogers, L.L. (1998) Drug Inf. J. 32:513–524.

[4] Coker, P.S. et al. (2003) Phytomedicine 10:133–138.

[5] Galsky, A.G. et al. (1980) Plant Physiol. 65:184–185.

[6] Meyer, B.N. et al. (1982) Planta Med. 45:31–34.