In-situ Clean-up and OPLC Fractionation of Chamomile Flower Extract Searching Active Components by Bioautography

Bioassay-guided isolation of antibacterial components of chamomile flower methanol extract was performed by OPLC with on-line detection, fractionation combined with sample clean-up in-situ in the adsorbent bed after sample application. The antibacterial effect of the fractions and the separated compounds remained on the adsorbent layer (do not overrun during OPLC separation) was tested with direct bioautography (DB) against the bioluminescent Pseudomonas savastanoi pv. maculicola and Vibrio fischeri. The fractions with great biologically activity were analysed by SPME-GC-MS and LC-MS/MS and the two active uneluted compounds were characterized by OPLC-MS using interface. Mainly essential oil components, coumarins, flavonoids, phenolic acids and fatty acids were identified in the fractions

Identification of Triterpenes and β-sitosterol in the Bark of Plane Tree Extracts

Plane tree is planted as ornamental tree in urban areas. This tree naturally sheds its bark during the spring; however, the shed bark is commonly regarded as a waste material without any significant application.On the other hand, the bark of plane tree may be an important source of industrially relevant compounds, most notably betulinic acid. In our study a Supercritical Fluid Ultra Performance Convergence Chromatography (UPC2) system coupled with Evaporative Light Scattering Detector (ELSD), along with conventional HPLC, GC-MS and NMR were successfully utilized to analyze triterpenes in the extracts from the bark of plane tree. We show that not only betulinic acid, but other important triterpenes: betulin, betulinic aldehyde and β-sitosterol are also present in the extract of the plane tree bark. Among these the main compound is betulinic acid, with up to an order of magnitude larger concentration than the other constituents. The applied extraction method has a significant role on the concentration of the different compounds in the extracts. Most notably, neat scCO2 is not suitable to extract the polar betulinic acid, however betulin and betulinic aldehyde can be extracted selectively

Antioxidant activity and phenolic composition of Corylus colurna

Corylus colurna L. (Turkish hazel), a common hazel species in Europe, could be considered as a source of pharmacologically important natural compounds, since other members of the Corylus genus have been reported to contain several constituents with beneficial biological activity. Nevertheless, its phytochemical exploration is still incomplete. In this study the potent antioxidant phenolic compounds in different parts of the plant were investigated. The phenolics in the leaves, bark, catkins and involucre of C. colurna possess notable scavenger activity on both DPPH and ABTS free radicals. The total polyphenol content shows significant correlation with the antioxidant activity of the samples. Twenty-three phenolic compounds - hydroxycinnamic acid derivatives, flavonoid derivatives and diarylheptanoids - were characterized in the C. colurna extracts by LC-DAD, LC-ESI-TOF and LC-ESI-QQQ-MS