Bioactive Metabolites from Spilanthes acmella Murr.

Abstract

Spilanthes acmella Murr. (Compositae) has been used as a traditional medicine for toothache, rheumatism and fever. Its extracts had been shown to exhibit vasorelaxant and antioxidant activities. Herein, its antimicrobial, antioxidant and cytotoxic activities were evaluated. Agar dilution method assays against 27 strains of microorganisms were performed. Results showed that fractions from the chloroform and methanol extracts inhibited the growth of many tested organisms, e.g. Corynebacterium diphtheriae NCTC 10356 with minimum inhibitory concentration (MIC) of 64-256 μg/mL and Bacillus subtilis ATCC 6633 with MIC of 128-256 μg/mL. The tested fractions all exhibited antioxidant properties in both DPPH and SOD assays. Potent radical scavenging activity was observed in the DPPH assay. No cytotoxic effects of the extracts against KB and HuCCA-1 cell lines were evident. Bioassay-guided isolation resulted in a diverse group of bioactive compounds such as phenolics [vanillic acid (2), trans-ferulic acid (5) and trans-isoferulic acid (6)], coumarin (scopoletin, 4) and triterpenoids like 3-acetylaleuritolic acid (1), β-sitostenone (3), stigmasterol and stigmasteryl-3-O-β-D-glucopyranosides, in addition to a mixture of stigmasteryl-and β-sitosteryl-3-O-β-D-glucopyranosides. The compounds 1–6 represent bioactive metabolites of S. acmella Murr. that were never previously reported. Our findings demonstrate for the first time the potential benefits of this medicinal plant as a rich source of high therapeutic value compounds for medicines, cosmetics, supplements and as a health food.

Differential Deterrent Activity of Natural Products Isolated from <i>Allophylus edulis</i> (Sapindaceae)

“…Compound 3, also isolated from fraction 2 ( Table 2) showed in its mass spectra a molecular ion m/z 412 which suggested the molecular formula C 29 H 48 O. In the 13 C NMR spectra, 29 signals were observed, confirming along with 1 H NMR signals and by comparison with bibliography data, that 3 corresponded to sitosterone [38], described in this study for the first time in this plant species. Sitosterone was tested in this study against M. persicae and S. littoralis, not being active against any of them.…”

Phytosterols isolated from endophytic fungus Colletotrichum gloeosporioides(Melanconiaceae)

“…The 1 H NMR spectrum of compound 3 showed the same pattern signals for 1 and 2 with the exception of the signal at δ H 3.50 referring to the carbinolic hydrogen H-3. In the 13 C NMR spectrum was observed an additional signal at δ C 199.3 (C-3) referent to carbonilic carbon, thus the compound 3 was identified as sitostenone (Prachayasittikul et al 2009). …”

Antimicrobial, antioxidant and anticancer activities of <i>Strychnos lucida</i> R. Br.

“…Medicinal plants with antioxidant and anticancer (Li et al, 2007;Charoensin, 2014); and with anticancer and antimicrobial (Tamokou et al, 2013) activities have been reported. In addition, a variety of medicinal plants have been documented to exert dual actions as antimicrobials and antioxidants (Prachayasittikul et al, 2008(Prachayasittikul et al, , 2009(Prachayasittikul et al, , 2010(Prachayasittikul et al, , 2012Treeratanapiboon et al, 2011).…”