Polyisoprenoids from leaves of Morus alba and M. nigra

Abstract

Trees or bushes of the genus Morus (mulberry) have been cultivated since antiquity. Mainly two species grow in Uzbekistan, M. alba and M. nigra. These species also include little studied varieties such as khasak-tut (used to feed silk worms), balkhi-tut (for fruit), ilon-tut and plakuchaya (as decorative plants), and shotut (M. nigra, for fruit) [1].Three polyisoprenoid alcohols, undeca-and dodecaprenols and solanesol, were isolated from silk-worm cocoons and leaves of M. alba [2]. Solanesol was not observed in the leaves. Moraprenols (polyprenols) from leaves of M. alba growing in Fergan Oblast were studied [3]. However, the quantitative composition of the polyprenologs was not reported. Polyprenols from M. nigra have not been reported.Recently a rather large number of preparations based on the use of polyprenols has appeared. In particular, the preparation gamapren (OOO GamaVetFarm, Russia) based on moraprenols is manufactured by phosphorylation of polyprenols isolated from Morus spp. The preparation exhibits antiviral action against Herpes viruses by suppressing the synthesis of viral proteins and stimulating the production of interferons [4].In continuation of research on plant polyprenols [5][6][7][8] and in order to compare the quantitative contents of M. alba and M. nigra polyprenols, we present results from a study of polyisoprenols from these two mulberry varieties growing in Tashkent Oblast.Total polyisoprenoids were isolated by the previously published method [9]. Dried and ground leaves (10 g) produced total polyisoprenoids in 2.6 and 3.2% yields. The content of total polyprenols was 1.37 and 1.97%, respectively, of the airdried leaf mass. The qualitative and quantitative compositions of the total polyisoprenoids were determined by high-performance TLC (HPTLC, Camag), by densitometry with UV detection at 210 nm, and by other alternate methods. HPTLC analysis used Sorbfil HPTLC-AF-UV plates (10 u 10). Plates were rinsed in distilled CHCl 3 and dried in air at 20-25°C for 10 min. The eluent was toluene:EtOAc (19:1). Compounds (1.0 mg) were dissolved in solvent (1 mL) and sampled (5 PL). The distance from the origin to the solvent front was 70.0 mm. The distance between tracks was 7.7 mm. Plates were dried in air at 20-25°C for 15 min.The standards were authentic samples of polyprenols from leaves of Asimina triloba (at least 96% pure) and those isolated by us from cotton leaves (at least 95% pure) of composition C 50 -C 65 . Standard samples of D-tocopherol and sitosterol were obtained from cotton leaves. Standard samples were prepared as described before [9]. Table 1 presents the results.According to the results, total polyisoprenoids contained polyprenols and D-tocopherol and sitosterol. The sitosterol contents in M. nigra and M. alba were almost identical. However, the amount of D-tocopherol was almost 13 times greater in leaves of M. nigra than in those of M. alba. The homologous composition of polyprenols from both M. nigra and M. alba included deca-, undeca-, and dodecaprenols with undecaprenol do...

Chemical and Biological Examination of Leaves of Morus Indica

“…Morus is an economically important genus evaluated for their edible fruits used in the preparation of marmalades, juices, liquors, natural dyes and their usage in sericulture, timber, medicine and cosmetic industries [6][7][8] . The genus is well-known for its richness in secondary metabolites including prenylated flavonoids, sterols, terpenes, anthocyanins, polyphenolic and Isoprenoidsubstituted phenolic compounds, phenyl bromides, arylbenzofurans and stilbene derivatives [9][10][11][12][13][14][15][16][17][18] which exhibited diverse biological activities like antibacterial, antifungal, antiviral, antinematodal, anti-cancer, anti-platelet, antioxidant, anti-inflammatory, antiproliferative, cytotoxic, hypoglycemic, analgesic, cardio protective and immuno regulating activities [19][20][21][22][23][24] . As a part of ongoing search for novel natural products of plant origin with potential biological activity, the current study was undertaken to investigate the chemical analysis and antimicrobial studies on the leaves of Morus indica , since no work has been reported from this species.…”