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Polyprenols and triterpenoids from leaves of Alcea nudiflora were studied for the first time. It was shown that the principal components of the unsaponified fraction were polyprenols, sterols, a phytol, and tocopherols. The composition of the polyprenols from Alcea nudiflora was established. Minor components of polyprenols with chain lengths 8, 9, and 14 isoprene units were observed for the first time in plants of the genus Alcea. A total of 28 terpene components of the unsaponified fraction, 26 of which were not previously observed in this species, were determined by GC-MS.Plants of the family Malvaceae are exceptional among leafy plants because of their high content of polyprenols (PPs), which are chemotaxonomic markers [1][2][3][4][5][6]. Such plants also have a characteristically high content of cyclopropane acids, which are practically not observed in plants of other families [7].Alcea nudiflora belongs to this family, is widely distributed, and is common in the plant cover of the whole Tian-Shan (Chatkal, Kuramin, Ugam, Pskom, etc. ranges) and Pamir-Alai (Alai, Turkestan, Nuratau, Zarafshan, etc. ranges) [8-10]. However, neutral triterpenoids and bioactive PPs from this plant are insufficiently studied [11].Various qualitative and quantitative analytical methods for PPs and dolichols from plant material have been reported. However, each of them has certain shortcomings. Thus, comparison of HPLC analyses of an extract and a chromatographic standard concentrate of PPs does not consider seasonal cycles of the component ratio in plant material according to vegetation periods. Furthermore, PPs and dolichols in certain plant species are present as esters of aliphatic acids that are unsuitable for HPLC analysis [12,13]. HPLC with refractive-index detection also has shortcomings. Normalization to the total peak area in the chromatogram does not consider differences in the extinction or refraction.PMR analysis of polyisoprenoid concentrates also has several shortcomings. A PMR spectrum of a PP sample is a superposition of resonances of similar structural fragments. The regular structure of the PPs produces total resonances that are stronger than those of impurities. This leads to a substantial overestimation of the quantitative characteristics of the studied PP fraction. Solanesol can be cited as an example [14].Use of densitometry of thin-layer chromatograms compared with a standard [15] also usually causes substantial overestimation of quantitative results because accompanying mono-, sesqui-, and diterpene alcohols overlap the spot for the PP fraction. Thus, borneol, cis-abienol, isoabienol, dehydroabietinol, and other alcohols that enhanced the intensity of the PP spot were present as impurities in the total fraction during a study of PPs from conifers [16,17]. Bisabolol was isolated from essential oil of cotton buds [18]. The chromatographic mobility of total extracted compounds depends on the chain length of the PPs in them and their form (as alcohols or esters). Therefore it is practically impossible to choose...

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Neutral substances, carbohydrates, and microelements from the aerial part of Silene viridiflora in addition to the protein content and its amino-acid composition were determined.The literature indicates that the genus Silene (Caryophyllaceae) has the highest content of ecdysteroids [1][2][3][4][5][6][7][8]. The maximum amount of phytoecdysteroids in the aerial part of plants of the genus Silene L. accumulates during budding and flowering [9]. The aerial part of S. viridiflora L. (budding phase) is a promising source of phytoecdysteroids for practical application.We carried out a comprehensive investigation of the chemical composition of the principal classes of natural compounds in S. viridiflora (ripening phase) collected in Tashkent at the experimental plot of the S. Yu. Yunosov ICPS of the ASRU [10].Fresh raw material was dried in the shade at 20-25°C to a residual moisture content of 2.7%. Ground leaves and roots were extracted with (C 2 H 5 ) 2 O, CHCl 3 , C 2 H 5 OH, and CH 3 OH to isolate the extracable substances (ES). The ES content in the leaves was 4.2, 3.8, 12.6, and 17.3% whereas the values in the roots were 2.4, 3.2, 6.0, and 13.1%, respectively. TLC of the neutral part identified [11] the following compounds: sitosterol, stigmasterol, polyisoprenoids, and α-tocopherol, the contents of which were 0.08, 0.02, 0.01, and 0.005% of the air-dried mass (ADM) of plant material.Proteins were extracted under alkaline conditions by borate buffer (0.2 M, pH 9.0) as before [12]. The protein content was determined by the Kjeldahl method [13]. The protein yield was 5.88 wt. %.The amino-acid composition of the isolated protein was determined after acid hydrolysis on an amino-acid analyzer. A total of 17 amino acids was observed in the hydrolysate. Table 1 lists the results. The quantitative determination of amino acids in the protein hydrolysate from S. viridiflora showed that the protein contained essential amino acids -histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine, valine, and arginine.The content of organic acids was determined as before [14]. It made up 8.32% calculated as malic acid in the absolute dry raw material.Remaining raw material was boiled with alcohol (80°) to determine the sugars soluble in alcohol (SSA). SSA extracts were purified with lead acetate (10%) and Na 2 SO 4 . Purified SSA solutions were evaporated to dryness. Paper chromatography (PC) (system 1) detected the following sugars that were characteristic of all plant organs: galactose, glucose, arabinose, and rhamnose in various ratios. Water-soluble polysaccharides (WSPS-1 and WSPS-2) were extracted by treating the raw material with water at room temperature and on a water bath at 70°C. Pectinic substances (PS) were obtained using oxalic-acid solution (0.5%). Table 2 gives the percent content of carbohydates and shows that the amount of free sugars is highest in leaves. WSPS-1 accumlated in roots; PS, in stems.Solutions of WSPS-1 and WSPS-2 were condensed and precipitated with alcohol (1:3). Dried samples were...

The accumulation dynamics of polyprenols in leaves of 1-, 2-, and 3-year-old Althaea armeniaca growing in Tashkent were studied according to vegetative phase. Optimal conditions for isolating the polyprenols were determined. It has been shown that the content of polyprenols was highest during fruiting in the second year of growth.

The genus Platanus (Platanaceae) is represented by four species in Central Asia [1]. The most widely distributed species is P. orientalis, eastern plane tree, the chemistry of which is little studied.The chemical composition of the leaves has been studied to a comparatively greater extent than that of the trunk bark. Phenolcarboxylic acids and flavonoids (hyperin, tiliroside) were isolated from the leaves. The hydrolysates contained quercetin, myricetin, cyanidin, and delphinidin [2,3]. Fallen leaves of plane tree are rich in α-tocopherol, its oxidized dimeric forms, and esters with higher fatty acids [4,5], and carbohydrates [6].The trunk bark contains neutral phytosterols (sito-and stigma-), α-tocopherol, and polyprenols [7] in addition to triterpenoids such as betulinic acid, betulinic aldehyde, platanoic and 3-dehydroplatanoic acids, and sitosterol [3,8].Trunk bark is used in folk medicine to treat dysentery, toothache, diarrhea, etc. [9, 10] and as an anticancer agent [11]. The goal of the present work was to investigate the chemical composition including proanthocyanidins of plane-tree trunk bark.Proanthocyanidins were isolated by fractionating the aqueous-alcohol extract of P. orientalis bark according to polarity using organic solvents. This produced low-molecular-weight, oligomeric, and polymeric fractions of proanthocyanidins.Column chromatography over finely crystalline cellulose and gel-filtration over Sephadex LH-20 isolated from the butanol fraction of the aqueous-alcohol extract two pure oligomeric glycosylated proanthocyanidins Pl-1 and Pl-7, which gave a red color with vanillin-H 2 SO 4 .Compound Pl-1 had empirical formula C 86 H 78 O 44 and molecular weight MW = 1814. Alkaline decomposition of Pl-1 under a N 2 atmosphere formed three compounds: fluoroglucinol (1) and protocatechoic (2) and gallic acids (3). Hydrolysis cleaved not only interflavane bonds but also flavan-3-ol units at the pyran heterocycle. Fluoroglucinol formed from ring A; phenolic acid, from ring B. Atoms C 3 -C 4 of ring C gave acetic acid [12,13].Acid hydrolysis of Pl-1 cleaved interflavane C-C bonds. This produced (-)-epicatechin-3-O-gallate (4), cyanidin (5), and glucose (6). Thiolytic cleavage of Pl-1 in the presence of thiophenol and acetic acid formed three compounds. The "lower" part of the molecule gave (-)-epicatechin-3-O-gallate (4); the "upper" blocks, a mixture of thioethers 7 and 8, which then decomposed catalytically in the presence of Raney Ni. The resulting compounds were identified by physicochemical and spectral properties as (-)-epicatechin (9) and (-)-epicatechin-3-O-gallate (4).