Anatomical features of the marshmallow (Althaea officinalis L.) root

Abstract

Marshmallow (Althaea officinalis L.) is a perennial herbaceous plant of the family Malvaceae, whose flowers, leaves and, especially roots, are used as drug in both folk and official medicine. Due to a high content of mucilage, the marshmallow root predominately serves for respiratory illnesses remedy. Anatomical features of a marshmallow root structure of different zones (root head, taproot and lateral roots) were observed by the analysis of permanent and temporal microscope slides with the additional application of histochemical methods in order to determine the mucilage localization in root tissues and cells. Results of anatomical structure of the marshmallow root showed that parenchyma cells and intercellular spaces of parenchyma of the secondary phloem and the secondary xylem represented a spot of the synthesis and the accumulation of the mucilage, whereas the older parts of the root (root head and taproot) could be characterized by dominance of the secondary xylem zone in difference to younger lateral roots with a more expressed zone of the secondary cork, i.e. the secondary phloem. These findings were confirmed by the application of a specific stain for mucilage with alcian blue. The ray cells are considered as the main accumulators of starch, which was confirmed through the application of the iodine reagent. Obtained results might be of a practical importance for the estimation of marshmallow drug quality, since the structure and the size of secretory parenchyma of the root probably corresponds with the content and the chemical composition of its active substances. .

Beli slez (Althaea officinalis L.) je višegodišnja zeljasta biljka iz familije Malvaceae, čiji se cvetovi, listovi i, posebno, koren koriste kao droga, kako u narodnoj, tako i u zvaničnoj medicini. Zbog velikog sadržaja sluzi koren belog sleza se prvenstveno upotrebljava kao sredstvo u lečenju respiratornih obolenja. Anatomske karakteristike građe korena belog sleza iz različitih zona (glava korena, glavni koren i bočni korenovi) proučavane su analizom trajnih i privremenih mikroskopskih preparata, uz primenu različitih histohemijskih metoda, u cilju identifikacije i lokalizacije sluznih materija. Rezultati analize anatomske građe korena belog sleza pokazali su da parenhimske ćelije i intercelularni prostori u parenhimu sekundarnog floema i sekundarnog ksilema predstavljaju mesta sinteze, odnosno akumulacije sluzi, pri čemu kod starijih zona korena (glava korena i glavni koren) se u tom smislu ističe zona sekundarnog ksilema, a u mlađim, bočnim korenovima, zona sekundarne kore, tj. sekundarnog floema, što je potvrđeno i histohemijskim analizama specifičnih bojenja sluznih materija alcijan plavim. Ćelije sržnih zrakova predstavljaju mesta akumulacije skroba, što je pokazano reakcijom sa Lugolovim rastvorom. Prikazani rezultati mogu biti od praktičnog značaja za poznavanje kvaliteta droge belog sleza, utoliko što građa i veličina zona sa sekretornim ćelijama korena ove biljke najverovatnije korespondira sa količinom i hemijskim sastavom aktivne supstance. .