The leaves of invasive annual plants represent an enormous renewable resource of polysaccharides and phenolic compounds for a large variety of applications. Impatiens parviflora DC. (small balsam) is naturalized in central Europe. The methanolic extract of its aerial parts shows insecticidal and repellent activity [1], whereas, the water and ethanolic extracts inhibitory effects on germination of seeds [2]. No attention has been devoted to the polysaccharide components of the leaves.
The objectives of the presented study were aimed at the overall characterization of non-cellulosic polysaccharides isolated from the extractive-free leaves. The air-dried leaves were treated with chloroform-ethanol and subsequently with methanol to separate phenolic components. The extracts were analyzed for the content and composition of their main components using HPLC with reverse phase and DAD detection. Non-cellulose polysaccharides were isolated by a five-step extraction procedure using as extractants water, 0.05 M ethylendiaminotetraacetic acid and dimethyl sulfoxide in the first three steps, and 1% and 5% NaOH in the last two steps. The polysaccharide fractions were characterized by yield, composition and structural features. Chemical and spectroscopic (FTIR, NMR) analyses of the first three fractions revealed the predominance of partially methyl-esterified pectins. The alkali-extracted polysaccharides contained low amounts of uronic acids (~0.4%) and higher amounts of total phenolics. All polysaccharides were contaminated to various extents with protein.
Acknowledgements
This research was sponsored by the VEGA grant No. 2/0083/13, the COST FP0901, the Ministry of Education, Youth and Sports of Czech Republic, Reg. N. LD11014 and by the CzechGlobe Reg. N. CZ.1.05/1.1.00/02.0073.
References
1. Pavela R., Vrchotová N., Šerá B. (2009). J. Biopest. 2, 48-51
2. Vrchotová N., Šerá B., Krejčová J. (2011). Plant Soil Environ. 57, 57-60
