Zeitschrift für Phytotherapie 2012; 33 - P06
DOI: 10.1055/s-0032-1313246

Cytoprotective effects of aqueous extracts from marshmallow roots (Althaea officinalis L.)

I Böker 1, J Sendker 1, T Stark 2, O Kelber 3, C Fink 3, A Hensel 1
  • 1University of Münster, Institute of Pharmaceutical Biology and Phytochemistry, Hittorfstr. 56, 48149Münster, Germany
  • 2Technical University of Munich, Chair of Food Chemistry and Molecular Sensory Science, Lise-Meitner-Str. 34, 85354 Freising, Germany
  • 3Steigerwald Arzneimittel GmbH, Havelstr. 5, 64295 Darmstadt, Germany

Extracts from the roots of Althaea officinalis L. (marshmallow) are traditionally used for treatment of dry cough and irritation of oral, pharyngeal or gastric mucosal membranes. This effect is due to the high content of mucilage polysaccharides. These polysaccharides are regarded as active compounds by forming bioadhesive layers on irritated mucus membranes [1] and by stimulating keratinocytes' and fibroblasts' cellular activity and proliferation rate [2].

In the present study, marshmallow roots were analyzed in regard of further secondary compounds which might cause the tissue protective activity of aqueous extracts. For the first time different homologues of N-phenylpropenoyl-L-amino acids (NPA) [3] with keratinocyte stimulating activity were found in the plant material and quantified by LC-MS/MS. Additionally, a high content of glycine betaine was found by LC-MS, beside higher amounts of the oligosaccharide raffinose. About 10% of the water extract was found to be constituted by free amino acids with proline, arginine and asparagine being the main components. These polar, low-molecular, water soluble compounds belong to the group of compatible solutes, for which protective effects against protein membrane systems during stress conditions are known [4]. Accordingly extracts and pure compounds were investigated for protective effects against the model enzymes lactate dehydrogenase (LDH) and glucose oxidase (GOD) under heat and dry stress conditions. Especially the aqueous extract and proline caused a higher residual activity of enzyme related to an untreated control. Therefore protective properties of these agents against proteins under the stress conditions can be claimed.

In vitro investigations on a human nasopharyngeal cell line (KB-cells) by WST-1-assay showed that neither the extract of marshmallow roots nor the compounds had any toxic effect on the KB-cells. From these data cytoprotective effects of the marshmallow extract may be explainable.

References: [1] Schmidgall J et al. Planta Med 2000; 66: 48–53

[2] Deters A et al. J Ethnopharmacol 2010; 127: 62–69

[3] Hensel A et al. Planta Med 2007; 73: 142–150

[4] Borges N et al. Extremophiles 2002; 6: 209–216