Open Access
Issue
BIO Web Conf.
Volume 11, 2018
IV(VI)th All-Russia Scientific-Practical Conference “Prospects of Development and Challenges of Modern Botany”
Article Number 00047
Number of page(s) 4
DOI https://doi.org/10.1051/bioconf/20181100047
Published online 21 August 2018

© The Authors, published by EDP Sciences, 2018

Licence Creative Commons
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

1 Introduction

The genus Bistorta (L.) Scop. species contain a variety of phenolic compounds - anthocyanins, catechins, flavones, flavonols, phenol carboxylic acids. It is well known their anti-inflammatory, antitumoral and antibacterial properties [1]. Biological activity of B. officinalis Delarbre and B. vivipara (L.) Delarbre [2], two widely spread in Eurasia species, is being active studied. Other species of the Bistorta genus, including B. alopecuroides, have been investigated insufficiently.

Species of the Bistorta genus are high polymorphic, their morphological races are poorly isolated and have a number of transitional forms. Studying phenolic compounds is urgent to reveal important biochemical signs, to clarify the taxonomic affiliation, and to identify perspective plants for medicine use.

The article objective is to investigate the phenolic compounds composition and content in leaves of B. alopecuroides from different populations of Siberia and the Far East.

2 Materials and Methods

The extracts of B. alopecuroides leaves of plants growing in Asian Russia were studied by HPLC. Table 1 shows sites of the samples collecting. All the plants were gathered during the flowering phase.

The analysis of glycosides in water-ethanol extracts was carried out by highperformance liquid chromatography on the analytical HPLC system consisting of Agilent 1200 liquid chromatograph with a diode array detector and ChemStation, a system for collecting and processing chromatographic data. The separation was done on a Zorbax SB-C18 column 4.6 x 150 mm in size, with a particle diameter of 5 μm using a gradient elution mode. To separate glycosides in the mobile phase, the methanol content in the aqueous solution of orthophosphoric acid (0.1%) varied from 32 to 33% in 27 minutes; from 33 to 46% since 27 to 38 minutes; from 46 to 56% since 38 to 50 minutes. The volume of the injected sample was 5 μ1, the eluent flow rate - 1 ml/min, under column temperature 26° C. [3]. The quantitative detection of individual compounds in eluates was carried with an external standard [4]. The content of phenolic compounds was calculated as milligram of quercetin equivalents per gram dry weight of sample (mg QE/g).

Table 1.

B. alopecuroides samples

3 Results

The analysis of the phenolic compounds composition in B. alopecuroides leaves using HPLC identify five components - vitexin (5) (tR=12,0), isovitexin (6) (tR=16,2), hyperoside (7) (tR=18,3), isoquercitrin (8) (tR = 19.8), rutin (9) (tR = 20.6). An absorption spectrum of unidentified components has two bands, one of which (II band) is in the low-wave part (250-290 nm), the other - in the long-wave one (340-380 nm) (band I), that is a characteristic feature of the flavonoid structure [5]. All components were attributed to phenolic compounds based on these data. Table 2 provides data on the content of individual components in leaves of B. alopecuroides plants. The sample number corresponds to Table

The relative standard deviation of repeatability in determining phenolic compounds was 0.011; tR - retention time, min; No. of compounds: 5 - vitexin (tR=12,0), 6 - isovitexin (tR=16,2), 7 - hyperoside (tR=18,3), 8 - isoquercitrin (tR = 19.8), 9 - rutin (tR = 20.6);

Table 2.

Phenolic compounds composition and content of B. alopecuroides plant leaves

4 Discussion

B. alopecuroides as a typical mesophyte lives in humid, more or less solonetz meadows, swamp margins, stony slopes and pebbles, meadow steppes. It is spread mainly in Transbaikalia, except for highlands, eastward it is noted in the Amur River valley and Pre-Khanka lowland [6]. It was marked 14 components in total for B. alopecuroides, 5 of them - 1, 10, 11, 13, 14 - were sporadic (Table 2). The maximum composition (9 components) was noted in sample No. 10 collected in the Republic of Buryatia at 1140 m above sea level, the minimum composition (6 components) - in the leaves of plants No. 6 and 9 from the Blagoveschensk District. Routine, isovitoxin and unidentified component No. 3 (tR = 9.2 min; UV spectrum - 273,355 nm) were found in all studied samples; hyperoside, isoquercitrine, astragaline and unidentified compound No. 4 (tR=11,1) were frequently occurring compounds as well. The phenolic components composition in leaves of B. alopecuroides from different populations is quite variable, which may be due to both environmental factors (soil composition, microclimate, altitude, technogenic pollution), and to a possible hybridization of this species with the widespread in Eurasia B. officinalis Delarbre. This hypothesis on the hybridization of B. alopecuroides and B. officinalis Delarbre, and the origin of the species B. elliptica (Willd. Ex Spreng.) Kom as a result of such hybridization belonged to N. N. Tsvelev [6]. In general, the Bistorta genus species are characterized with a great polymosphism, they are often represented by numerous weakly differentiated races [7]. M.G. Popov [8] noted that B. alopecuroides in a typical form occurs only in "Proper Dauria: for example, Nerchinsk Plant and along the River Argun". Phenolic compounds are involved in many important processes of plant metabolism, and morphological variability is closely related to changes in chemical composition.

Variability was marked for the quantitative content of phenolic compounds as well. The smallest content of phenolic compounds (5.26 mg QE/g) was fixed in plant leaves collected in the Republic of Buryatia (No. 1) growing under the mixed forest canopy, the greatest one (20.8 mg QE/g) in plants from Tunka District in Buryatia (No. 5), which grew at 919 m above sea level. Plants gathered at 1140 m above sea level (No. 10) have a high content (15.64 mg QE/g) as well. Samples growing in Blagoveshchensk city surroundings (No. 6, 9) collected near the road contain up to 13.87-17.04 mg QE/g of phenolic compounds with the lowest composition of 6 components that is confirmed by numerous references on the enhanced synthesis of phenolic compounds, including flavonoids, under effect of various stresses. The flavonoid accumulation by plants is a mechanism to protect their photosynthetic apparatus from extensive oxidation under the influence of higher insolation or man-made contamination [9,10]. In the remaining samples the phenolic compounds content in leaves was about 7.5 mg QE/g.

In conclusion, the composition and content of phenolic components of B. alopecuroides from different populations of Siberia and the Far East is quite variable and depends on environmental factors, such as soil composition, microclimate, altitude, technogenic pollution. Three components were identified, which were found in B. alopecuroides plant leaves of all studied populations: isovitixine, rutin and unidentified component No. 3 (tR = 9.2 min; UV spectrum 273,355 nm). B. alopecuroides plants growing in highlands and under conditions of technogenic pollution have the highest content of phenolic compounds that confirms the adaptive role of phenolic compounds in plant metabolism.

References

  • M. Adiba, I. H. M. Tabarak, Glob J. Res Med Plants Indigenous Med 2, 669-674 (2013) [Google Scholar]
  • M. S. Voronkova, G. I.Vysochina, Chem. Sustainable Development 22, 209-215 (2014). [Google Scholar]
  • E. P. Khramova, E. K. Komarevtseva, Vegetative Resources 44, 96-102 (2008) In Russ. [Google Scholar]
  • T. A. Van Beek, J. Chromatography A 967, 21-35 (2002) [CrossRef] [Google Scholar]
  • E. P. Khramova, Chem. Vegetative Raw Materials 1, 185-193 (2014.) In Russ. [Google Scholar]
  • N. N. Tsvelyov. Vascular plants of the Soviet Far East (4, Nauka, Leningrad, 1989) In Russ. [Google Scholar]
  • V. V. Petrovsky, Arctic flora of the USSR 5 (Nauka, Moscow, 1966.) In Russ. [Google Scholar]
  • M. G. Popov, Flora of Middle Siberia 2 (Nauka, Moscow, Leningrad, 1959) In Russ. [Google Scholar]
  • E. Grotewold, The science of flavonoids (Springer, New York, 2006) [CrossRef] [Google Scholar]
  • M. S. Voronkova, G. I.Vysochina, Contemp. Probl. Ecology 6, 565-574 (2013) [Google Scholar]

All Tables

Table 1.

B. alopecuroides samples

Table 2.

Phenolic compounds composition and content of B. alopecuroides plant leaves

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