New Lignans from the Aerial Parts of Rudbeckia laciniata

Three new furofuran lignans, (+)‐4,4′‐O‐diangeloylpinoresinol ( 1 ), (+)‐4,4′‐O‐diangeloylmedioresinol ( 2 ), and (+)‐4,4′‐O‐diangeloylsyringaresinol ( 3 ), together with the known compound (+)‐syringaresinol, were isolated from the MeOH extract of Rudbeckia laciniata. The structure elucidation of these compounds were based on 1D‐ and 2D‐NMR, and HR‐ESI‐MS data. The additional structural evidence was obtained from alkaline hydrolysis of the compounds.     

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of Drypetes laciniata

A new friedelane-type triterpene named 3β-hydroxyfriedelane-7,12,22-trione,as well as nine known compounds were isolated from the whole stems of Drypetes laciniata Hutch.(Euphorbiaceae).Their structures were established on the basis of spectroscopic methods.The new triterpene derivative and a known saponin were tested for antimicrobial and antifungal activities and they appeared to be moderate active.     

The RP-HPLC analysis of anthocyanins

Summary Conditions were determined for the separation of a complex set of anthocyanins (free aglycones, mono- and multiglycosides and esterified forms) by HPLC. The optimised gradient elution method was then used to carry out qualitative and quantitative analysis of anthocyanin compounds present in the callus tissue ofRudbeckia hirta L. and the tubular flowers of the soil-based plant. The summary content of anthocyanin pigments and the content of the main pigment was identified in the analysed biomass. The method developed is useful for the purposes of monitoring the process of biosynthesis of anthocyanins in tissues obtained through in vitro cultures. The advantages of the method for anthocyanins and its application to other anthocyanin-rich materials are also discussed.