Bioassay-guided isolation of anti-algal constituents from Inula helenium and Limonium myrianthum

Abstract

Over 70 crude plant extracts, primarily from Kazakhstan, were screened against the freshwater phytoplanktons Oscillatoria perornata and Selenastrum capricornutum. Extracts from Limonium myrianthum and Inula helenium both demonstrated selective inhibition against the odorproducing cyanobacterium O. perornata compared to activity against the green alga S. capricornutum. Bioassay-guided fractionation of the L. myrianthum dichloromethane extract resulted in the identification of nepodin, torachrysone, chrysophanol, and physcion. Nepodin demonstrated the desired selective inhibition with lowest-complete-inhibition concentration values of 100 µg/mL and >100 µg/mL towards O. perornata and S. capricornutum, respectively. Similarly, chrysophanol also demonstrated the desired selective inhibition with lowest-completeinhibition concentration values of 10 µg/mL and >100 µg/mL, respectively. Bioassay-guided fractionation of the I. helenium hexane extract resulted in the isolation of alantolactone, isoalantolactone, and 11αH,13-dihydroisoalantolactone. Activities of these three isolated constituents as well as those of synthetic isomers are reported.

Isolation and Identification of Flavobacterium columnare and Streptococcus iniae Antibacterial Compounds from the Terrestrial Plant Atraphaxis laetevirens

“…The gross structures of compounds 1, 2, and 3 (Figure 1) were elucidated by analyses of EIMS and 1 H NMR spectra, which were in agreement with literature data of chrysophanol, physcion, and nepodin, respectively. 16,17 The gross structure of compound 4 (Figure 1) was elucidated by analyses of EIMS and 1 H and 13 C NMR spectra, which were in agreement with the literature data of emodin. 16 This is the first report on the presence of compounds 1−4 in A. laetevirens.…”

“…Previous studies have isolated many bioactive compounds from plants collected in Kazakhstan, thereby demonstrating the benefits of sourcing plants from this region for the discovery of pesticide candidates. − In the present study, 18 crude extracts of plants collected in Kazakhstan were screened for toxicity against the Gram-negative bacteria F. columnare (isolate ALM-00-173) and E.…”

“…13 C NMR (CDCl 3 ) δ: 191.7 (C-9), 182.2 (C-10), 166.5 (C-3), 166.3 (C-1), 163.3 (C-8), 149.6 (C-6), 136.6 (C-14), 134.2 (C-11), 125.0 (C-7), 121.5 (C-5), 114.5 (C-12), 110.5 (C-13), 109.8 (C-4), 108.9 (C-2), 22.1 (CH 3 ). EIMS m/z: 270.2.…”

“…General Procedures. 1 H and 13 C nuclear magnetic resonance (NMR) spectra were recorded on a Varian Unity Inova AS600 spectrometer (Varian, Palo Alto, CA). Electron impact mass spectrometry (EIMS) spectra were recorded on a Varian CP-3800 gas chromatograph coupled to a Varian Saturn 2000 mass spectrometer (Varian, Inc., Palo Alto, CA).…”

Métodos de control de las floraciones de cianobacterias en aguas continentales

“…(lavanda), Rosmarinus officinalis (romero), Laurus nobilis (laurel), Mentha suaveolens (mastranzo), Fraxinus angustifolia (fresno), Populus sp. (chopo), Sambucus nigra (saúco), Innula helenium (énula), Limonium myrianthum (lavanda de mar)-, con la esperanza de que presenten propiedades cianotóxicas (Schrader et al, 1998b;Ridge et al, 1999;Schrader & Harries 2001;Schrader et al, 2002;Schrader, 2003;Cantrell et al, 2007;Barros et al, 2010). Estos compuestos pertenecen a grupos de alcaloides, fenoles y polifenoles, quinonas, terpenos, ácidos orgánicos, etc.…”