Effect of structurally related flavonoids from Zuccagnia punctata Cav. on Caenorhabditis elegans.

Zuccagnia punctata Cav. (Fabaceae), commonly called jarilla macho or pus-pus, is being used in traditional medicine as an antiseptic, anti-inflammatory and to relieve muscle and bone pain. The aim of this work was to study the anthelmintic effects of three structurally related flavonoids present in aerial parts of Z. punctata Cav. The biological activity of the flavonoids 7-hydroxyflavanone (HF), 3,7-dihydroxyflavone (DHF) and 2´,4´-dihydroxychalcone (DHC) was examined in the free-living nematode Caenorhabditis elegans. Our results showed that among the assayed flavonoids, only DHC showed an anthelmintic effect and alteration of egg hatching and larval development processes in C. elegans. DHC was able to kill 50% of adult nematodes at a concentration of 17 µg/mL. The effect on larval development was observed after 48 h in the presence of 25 and 50 µg/mL DHC, where 33.4 and 73.4% of nematodes remained in the L3 stage or younger. New therapeutic drugs with good efficacy against drug-resistant nematodes are urgently needed. Therefore, DHC, a natural compound present in Z. punctata, is proposed as a potential anthelmintic drug.

Inhibition of arachidonic acid metabolism by the Andean crude drug Parastrephia lucida (Meyen) Cabrera.

ETHNOPHARMACOLOGICAL RELEVANCE: Parastrephia lucida (Meyen) Cabrera is used in the traditional medicine of Argentinean highlands as an antiseptic and anti-inflammatory medicinal plant. To give scientific support to the ethnopharmacological claim of Parastrephia lucida as an anti-inflammatory crude drug the effect of Parastrephia lucida extracts and fractions was assessed on key enzymes of the biosynthesis of pro-inflammatory eicosanoids mediators from arachidonic acid (AA). MATERIALS AND METHODS: A bio-guided fractionation of the plant extract was carried out to find out the compounds or mixtures responsible for the anti-inflammatory effect. The extracts and fractions were tested in vitro for their ability to inhibit the enzymes cyclooxygenase (COX)-1 and COX-2, lipoxygenase (LOX) and phospholipase (sPLA2). Fractions were analyzed by HPLC-MS, HPLC-ESI-MS/MS and NMR to relate the effect with groups of secondary metabolites. RESULTS: Parastrephia lucida was more effective inhibiting COX and sPLA2 than LOX. Assay-guided isolation led to the active fractions C and F which showed different effect on the selected enzymes. The fraction C was more effective inhibiting LOX while fraction F showed better activity against sPLA2 and COX-2. Both fractions were further worked-up following the isolation of the anti-inflammatory agents with the selected enzyme assays. The main compounds identified in the most active fractions were 5,4'-dihydroxi-7-methoxyflavanone, apigenin, apigenin methyl ether and apigenin trimethyl ether, methyl and dimethyl ethers from quercetin, kaempferol and luteolin methyl ether, ferulic acid esters, cinnamic acid and vanillin. CONCLUSIONS: Parastrephia lucida extract inhibit AA metabolism via several enzymes. The results give support to the traditional use of this plant for the treatment of inflammatory disorders.

Antimicrobial phenylpropanoids from the Argentinean highland plant Parastrephia lucida (Meyen) Cabrera.

ETHNOPHARMACOLOGICAL RELEVANCE: The Argentinean highland plant Parastrephia lucida (Meyen) Cabrera is used in traditional medicine as an antiseptic and anti-inflammatory crude drug. AIM OF THE STUDY: To relate the antimicrobial effect of the crude drug with the constituents of the active fractions and traditional use. MATERIALS AND METHODS: Assay-guided isolation of the methanol (MeOH) plant extract was carried out using bacteria and yeasts as target organisms. Both ATCC and local strains were included in the study. The antimicrobial fractions and compounds were detected by bioautographic assays. Minimum inhibitory concentrations (MIC) of each extract and fraction were determined and compared with reference antibiotics. Fractions were analyzed by HPLC-DAD, GC-MS, (1)H NMR and (13)C NMR. RESULTS: From the MeOH extract of the plant, assay-guided isolation of the antimicrobial constituents led to 12 phenylpropanoids and two simple phenolics. Most of the compounds occurring in the active fractions were E-caffeoyl or E-cinnamoyl esters including prenyl and phenethyl derivatives. The MIC values of the most active fractions ranged between 12.5 and 200 µg/mL against reference strains and local isolates of Staphylococcus aureus and Enterococcus faecalis. CONCLUSIONS: The antimicrobial effect found in the crude drug was associated with mixtures of phenylpropanoids, including prenyl and phenethyl esters of caffeic and cinnamic acids. The results support at least in part the traditional use of the plant as local antiseptic.