ABSTRACT
The phytochemical study of flowering shoots of Caragana bungei Ledeb., Fabaceae, collected in Tuva Republic (Russian Federation) resulted in the isolation of sixteen compounds identified as β-sitosterol, β-sitosterol-3-O-glucoside, umbelliferone, kaempferol, quercetin, isorhamnetin-3-O-glucoside, isoquercitrin, rutin, narcissin, nicotiflorin, caffeic acid, 3-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, gallic acid and sucrose. The structures of the compounds were established by spectral analyses. This is the first phytochemical investigation of C. bungei. The nicotiflorin, phenylpropanoids and gallic acid were isolated from the Caragana genus for the first time.
ABSTRACT
The melanoidin pigment (OS-M) was isolated from fermented leaves of Orthosiphon stamineus Benth. (Lamiaceae), with a 0.37% yield (from dry plant weight), and characterised. OS-M is a phenolic polymer with a molecular weight Keywords: of 4.4 kDa. Determination of basic physicochemical parameters using elemental antioxidant activity analysis, functional group analysis, UV-Vis-and FTIR-spectroscopy of OS-M fermented leaves indicated that the isolated polymer was similar to typical melanoidins. Experimental Lamiaceae data show that aromatic fragments dominate the OS-M structure, which also contains melanoidin a small amount of aliphatic fragments. Investigation into the antioxidant activity of Orthosiphon stamineus Benth OS-M under in vitro conditions demonstrated that O. stamineus melanoidin has a scavenging effect against free radicals (DPPH, ABTS+, O2-) and NO molecules, inactivates molecules of H2O2, chelates Fe2+-ions and oxidises NADH.