Five geranylflavonoids, one prenylated flavonoid, and a simple flavanone were isolated from an ethanolic extract of Paulownia tomentosa fruit. Tomentodiplacol (1), 3'-O-methyl-5'-methoxydiplacol (2), 6-isopentenyl-3'-O-methyltaxifolin (3), and dihydrotricin (4) are reported from a natural source for the first time and 3'-O-methyldiplacone (6) for the first time from the genus Paulownia. The structures of the compounds were determined by mass spectrometry, including HRMS, and by 1D and 2D NMR spectroscopy. The cytotoxicity and DPPH (2,2-diphenyl-1-picrylhydrazyl)-quenching activity of some of these compounds were tested, with diplacone proving to be the best antioxidant, although the most cytotoxic compound.

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Previously tested n-hexane extracts of the Scorzonera latifolia showed promising bioactivity in vivo. Because triterpenes could account for this activity, n-hexane extracts were analyzed by HPLC to identify and quantify the triterpenes as the most abundant constituents. Other Scorzonera and Podospermum species, potentially containing triterpenic aglycones, were included in the study. An HPLC method for simultaneous determination of triterpene aglycones was therefore developed for analysis of Podospermum and Scorzonera species. n-Hexane extracts of root and aerial parts of S. latifolia, ten other Scorzonera species and two Podospermum species were studied to compare the content of triterpenes. HPLC was used for the qualitative and quantitative analysis of α-amyrin, lupeol, lupeol acetate, taraxasteryl acetate, 3-β-hydroxy-fern-7-en-6-one acetate, urs-12-en-11-one-3-acetyl, 3-β-hydroxy-fern-8-en-7-one acetate, and olean-12-en-11-one-3-acetyl. Limits of detection and quantification were determined for each compound. HPLC fingerprinting of n-hexane extracts of Podospermum and Scorzonera species revealed relatively large amounts of triterpenes in a majority of investigated taxa. Lupeol, lupeol acetate, and taraxasteryl acetate were found in a majority of the species, except S. acuminata. The presence of α-amyrin, 3β-hydroxy-fern-7-en-6-one-acetate, urs-12-en-11-one-3-acetyl, 3β-hydroxy-fern-8-en-7-one-acetate, and olean-12-en-11-one-3-acetyl was detected in varying amounts. The triterpene content could correlate with the analgesic and anti-inflammatory activity of Scorzonera, which was previously observed and Scorzonera species that have been determined to contain triterpenes in large amounts and have not yet been tested for their analgesic activity should be tested for their potential analgesic and anti-inflammatory potential. The presented HPLC method can be used for analysis of triterpene aglycones, for example dedicated to chemosystematic studies of the Scorzonerinae.

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A series of homoisoflavonoids and chalcones, isolated from the endemic tropical plant Dracaena cinnabari Balf. (Agavaceae), were tested for their potential to inhibit cytochrome P4501A (CYP1A) enzymes and Fe-enhanced in vitro peroxidation of microsomal lipids in C57B1/6 mouse liver. The effects of the polyphenolic compounds were compared with those of prototypal flavonoid modulators of CYP1A and the well-known antioxidant, butylated hydroxytoluene. 2-Hydroxychalcone and partly 4,6-dihydroxychalcone were found to be strong inhibitors of CYP1A-dependent 7-ethoxyresorufin O-deethylase (EROD) activity in vitro comparable to the effects of quercetin and chrysin. The first screening of flavonoids and chalcones of Dracaena cinnabari for antioxidant activity was done in an in vitro microsomal peroxidation assay. While chalcones were shown to be poor antioxidants, 7,8-methylenedioxy-3(4-hydroxybenzyl) chromane, as one of the tested homoisoflavonoids, exhibited a strong antioxidant activity comparable to that of the strongest flavonol antioxidant, quercetin.

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The European grapevine moth (EGVM),Lobesia botrana, is a major pest of grapes in Europe. Females are attracted to a nonhost plant: tansy (Tanacetum vulgare L.), which is a common weed in Slovakian vineyards. A steam distillate extract of tansy flowers was analyzed by means of a GC-EAG technique to screen constituents detected by the olfactory receptors of EGVM females. From more than 200 GC peaks, nine peaks corresponding to monoterpenoids released an EAG response in more than 70% of the females (N=15):p-cymene,d-limonene,α-thujene,α-thujone,β-thujone, thujyl alcohol, terpinene-4-ol, (Z)-verbenol, and piperitone. The steam distillate of tansy as well as a synthetic blend of identified compounds released consistent attraction in a field cage. The use of nonhost plants and host plant odors in integrated pest management is discussed.