Botanical Investigation of Fallopia Dumetorum (L.) Holub (Polygonaceae) and Qualitative and Quantitative Assessment of its Polyphenolic Compounds

Abstract

Abstract Background: Considering the continuous need to find new sources of polyphenolic compounds, we performed a pharmacognostical examination of the species Fallopia dumetorum (L.) Holub sin. Polygonum dumetorum L. (Polygonaceae). The plant is common in the plain regions of Romania and has not been exploited therapeutically. Materials and method: Microscopic examination was performed on cross-sections, surface preparations and on powder obtained from the aerial parts of the flowering plant. Qualitative chemical analysis was realized by phytochemical screening and thin layer chromatography (TLC). Phenolic compounds were assayed by spectrophotometric methods: flavonoids expressed as rutin (with aluminium chloride), phenolcarboxylic acids expressed as chlorogenic acid (Arnow’s method) and proanthocyanidins expressed as cyanidin chloride (in acidic medium, by conversion to anthocyanins). Results: The species has the following microscopic characters: anomocytic stomata, druses of calcium oxalate, sessile, pluricellular glandular hairs and pollen grains with smooth exine. Polysaccharides, reducing compounds, coumarins, sterols/triterpenes, phenol-carboxylic acids, flavones, proanthocyanidins, tannins and carotenoids were identified by phytochemical screening; chlorogenic acid, caffeic acid, quercetin and stigmasterol/beta-sitosterol were detected by TLC. F. dumetori herba has a content of 1.49 ± 0.105 g% polyphenol-carboxylic acids, 0.40 ± 0.087g% flavonoids and 0.18 ± 0.002 g% proanthocyanidins. Conclusions: We have characterized pharmacognostically the native species F. dumentorum. Due to its content in phenolic compounds it might serve as a source of polyphenols.