Identification of sesquisabinene B in carrot (Daucus carota L.) leaves as a compound electrophysiologically active to the carrot psyllid (Trioza apicalis Förster)

• The Carrot psyllid, Trioza apicalis Förster (Homoptera: Psylloidea: Triozidae) is one of the major insect pests of carrots (Daucus carota L.) in parts of northern and central Europe. Gas chromatography–single-sensillum recording (GC–SSR) previously confirmed several active compounds in a carrot leaf extract, but the most active compound remained unidentified. Mass fragmentation patterns observed from the unidentified active compound when analyzed by gas chromatography and mass spectrometry (GC–MS) was used to propose β-sesquiphellandrene and α-cis-bergamotene to be candidates as the unidentified compound. The compounds were synthesized and their mass spectra were nearly identical with the unknown active compound. But, the retention times differed from the compound in the carrot leaf extract. Thus, to obtain the unidentified compound pure enough and in adequate amounts for nuclear magnetic resonance (NMR) analysis, preparative gas chromatography was applied to separate and concentrate this biologically active compound. Analysis by liquid chromatography quadrupole time of flight mass spectrometry (LC–QTOF) confirmed the unidentified compound to be a compound with the formula of C 15 H 24 and together with GC–MS, 1 H and 13 C NMR analysis sesquisabinene B was identified as the unidentified compound in the extract. GC–SSR was then used to finally confirm the biological activity of sesquisabinene B isolated from the carrot leaf extract via preparative GC.

Subject headings

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

LANTBRUKSVETENSKAPER  -- Lantbruksvetenskap, skogsbruk och fiske -- Jordbruksvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agriculture, Forestry and Fisheries -- Agricultural Science (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Keyword

Analysis

Preparative gas chromatography

Single-sensillum recording

Synthesis

α-cis-Bergamotene

β-Sesquiphellandrene

Synthesis

Publication and Content Type

art (subject category)

ref (subject category)