Plantago asiatica L. is an endemic terrestrial plant species which grows in Eastern Siberia and the Russian Far East, and is also found in East Asian countries; it is not a pharmacopeia species.We report here a comparative phytochemical and pharmacognostic analysis of the leaves of Plantago asiatica L. and Plantago major L. Pectins were isolated from the leaves of both plantain species and their contents in raw materials were determined (12.80 ± 0.56

Low esterified pectin was isolated from the seagrass Zostera marina . Dynamics of the isolation process for the pectin from this seagrass was investigated. Two pectin derivatives: galacturonide (A) with molecular weight 30.55 kDa and galacturonide (B) with molecular weight 3.94 kDa were obtained using acidic hydrolysis of the native pectin from Zostera marina . Molecular weight parameters (Mw, Mn, Mw/Mn) of this pectin and its derivatives as well as of commercial apple pectin were determined using gel-filtration chromatography method. Comparative assessment of Cd 2+ , Pb 2+ , Y 3+ -binding activity of the native Zostera pectin, galacturonides A and B, and commercial apple pectin was performed. The results showed that galacturonide A with molecular weight 30.55 kDa possesses highest metal-binding capacity and may be considered as a candidate for development of medicines with metal-binding activity.

DEvELOPMENt OF A MEthOD OF stANDARDIzAtION FOR LOw-MOLECULAR PECtINs E.V. Khozhaenko1, 2, R.Yu. Khotimchenko1, 2, V.V. Kovalev1, E.A. Podkorytova1, M.Yu. Khotimchenko1, 2 1 Institute of Marine Biology named after A.V. Zhirmunskiy Far Eastern Branch of RAS (17 Palchevskogo St. Vladivostok 690041 Russian Federation), 2 School of Biomedicine of Far Eastern Federal University (8 Sukhanova St. Vladivostok 690950 Russian Federation) background. Object of this study was developing a method of stan‐ dardization of low‐molecular pectins‐oligouronids according to the chain‐length distribution for subsequent validation. Methods. Standardization of oligouronids was carried out using ex‐ clusion chromatography techniques and analysis of reducing end groups. The authors studied the eluent influence on the separation of oligouronids with molecular weights of 2.8–15.5 kDa on column with hydrophilic sorbent Shodex Asahipak GS‐320 7E. Results. It has been established that the optimal separation of oli‐ gouronids on molecular weight is achieved in 0.1M of sodium ni‐ trate at 35 °C and the eluent speed of 0.8 ml/min. The values of mass average and number average for oligouronids molecular weights obtained respectively with the exclusion chromatography methods and analysis of the end groups were similar that indicates a rela‐ tively small value of polydisperse samples and the validity of these methods for standardizing oligouronids. Conclusions. When comparing the modified tetrazolium method and Nelson method for analyzing oligouronids end groups it was determined that Nelson method allows to obtain more accurate and reliable results and it is applicable for oligouronids standard‐ ization.

Подкорытова Елена Алексеевна – канд. биол. наук, научный сотруд‐ ник лаборатории фармакологии Института биологии моря ДВО РАН; e‐mail: eapodkorytova@mail.ru DEvELOPMENt OF tEChNOLOgy FOR qUICk-DIssOLvINg FORM OF sODIUM ALgINAtE V.V. Kovalev1, R.Yu. Khotimchenko1, 2, E.A. Podkorytova1, E.V. Khozhaenko1, 2 1 Institute of Marine Biology named after A.V. Zhirmunskiy FEB RAS (17 Palchevskogo St. Vladivostok 690041 Russian Federation), 2 School of Biomedicine of Far Eastern Federal University, (8 Sukhanova St. Vladivostok 690950 Russian Federation) background. Brown algae polysaccharides – are the alginates widely used in food and pharmaceutical industries as health promoting medicines in case of poisoning with heavy metals salts and radio‐ nuclides. A significant shortcoming of the alginates is their poor solubility. The purpose of research is development of a method en‐ hancing the sodium alginate solubility based on a transferring the part of uronic acids residues in the alginate molecule to the calcium salts form. Methods.The article covers the influence of calcium content on the alginate solubility. The researchers formed sorption isotherm of cal‐ cium ions by sodium alginate in the environment of 50 % ethanol and obtained the alginate samples containing from 0.2 to 6.82 % of calcium. Also they studied the hydrogels properties of the obtained samples of calcium alginate. Results. It was found that in the case of calcium content in the alginate less than 4.44 % a partial dissolution of the alginate gel starts, while calcium content less than 0.8 % promotes a complete dissolution. There have been also an estimation of dissolution rate for various alginate samples. Calcium alginate samples containing 0.2‐0.8 % of calcium showed a higher rate of dissolution by 6.2‐13.4 times than the original sodium alginate. Conclusions. Technology for producing incomplete calcium salts of alginates may be a new and very efficient approach to the prob‐ lem of their solubility and, therefore, improvement of consumer properties.