<i>Curtisia dentata</i> (Cornaceae) leaf extracts and isolated compounds inhibit motility of parasitic and free-living nematodes

Abstract

Haemonchus contortus and Trichostrongylus colubriformis are among the most important parasitic nematodes of small ruminants. Caenorhabditis elegans, a free-living nematode, is used as a model for evaluating anthelmintic activity of a variety of test substances. Extracts of several medicinal plants are useful in vitro and in vivo against nematode development. Extracts of Curtisia dentata, a South African medicinal plant, and compounds isolated from leaves of this plant were investigated for anthelmintic activity against T. colubriformis, H. contortus and C. elegans. The acetone and dichloromethane extracts were active against all nematodes at concentrations as low as 160 μg/mℓ. Betulinic acid and lupeol were active against the parasitic nematodes only at the high concentrations of 1 000 and 200 μg/mℓ, respectively. All compounds were effective against C. elegans with active concentrations as low as 8 μg/mℓ. Betulinic acid was less active than lupeol and ursolic acid against C. elegans. The acetone and dichloromethane extracts were also active against C. elegans with a concentration of 0.31 mg/mℓ resulting in almost 80 % inhibition of larval motility. The use of free-living nematodes may provide information on the activity of potential anthelmintics against parasitic nematodes. Extracts of various medicinal plant species may provide solutions to ill-health of small ruminants caused by parasitic nematodes in poor communities of southern Africa.

In vitro anthelmintic activity of the Zizyphus joazeiro bark against gastrointestinal nematodes of goats and its cytotoxicity on Vero cells

“…The occurrence of changes that comprise the activity of these enzymes can reduce the hatching rate (Rogers and Brooks, 1977). BA showed no ovicidal action; however, a study by Shai et al (2009) demonstrated that this acid inhibited motility around 75% of L3 larvae of H. contortus in the same concentration used in the present work. The HE, which has BA among other compounds, showed less activity on eggs compared to AE and CE.…”

“…The determination of the concentrations used was based on results from pilot experiments, and were well-defined concentrations of 0.8; 1.2; 1.8; 2.7; and 4 mg / mL for extracts and fractions. The concentrations of BA (1.0, 0.75 and 0.5 mg / mL) were defined based on a study by Shai et al (2009). In the 1 mg / mL of BA, the study showed action on larvae of H. contortus.…”

“…There are no reports on the anthelmintic activity of both saponins of this plant. Another constituent found in the bark of Zizyphus joazeiro known as betulinic acid (BA) has showed a variety of biological activities ranging from the inhibition of the replication of the human immunodeficiency virus (HIV), the antioxidant (Yogeeswari and Sriram, 2005) and anthelmintic properties (Shai et al, 2009). …”

In vitro anthelmintic activity of aqueous extract of Crassocephalum crepidioides (Benth.) S. Moore on Haemonchus contortus.

“…Haemonchus contortus and Trichostrongylus colubriformis are listed among the top ten of most important ruminant's parasites [5][6][7]. Haemonchus contortus causes anaemia, haemorrhagic gastroenteritis, hypoproteinemia partly manifested as submandibular oedema 'bottle jaw' and sudden death [8].…”

Thin‐layer Chromatography of Plants, with Chemical and Biological Detection Methods

“…Contrary to immersion, direct bioautography is performed without agar: immediately before use, microorganisms are usually transferred from their solid culture medium to a sterile fresh broth containing all required nutrients for proper microbial growth and having a viscosity compatible with spraying if necessary. After appropriate incubation, zones of growth inhibition are observed naturally for spore-producing fungi and pigmented bacteria or revealed via tetrazolium salts ( Figure 4) (Shai et al, 2009). An alcoholic solution can be subsequently sprayed onto the entire layer to fix microorganisms.…”