Unravelling the anthelmintic bioactives from Jasminum grandiflorum L. subsp. Floribundum adopting in vitro biological assessment.

ETHNOPHARMACOLOGICAL RELEVANCE: Jasminum grandiflorum L. is a medicinal plant widely used in the traditional system of Medicine as an anthelmintic in ringworm infections, for treating ulcers, stomatitis, skin diseases, and wounds. AIM OF THE STUDY: The emergence of resistance by different parasites to currently used chemicals has been reported. There are increasing needs for more effective and safer parasiticides. Therefore, the current study was designed to investigate the methanolic extract of the aerial parts of J. grandiflorum subsp. Floribundum (JGTE) to confirm its traditional uses as anthelmintic through a bioassay-guided fractionation and isolation of the active components with anthelmintic activity. MATERIALS AND METHODS: The JGTE was partitioned into dichloromethane (DCM-F) and n-butanol (BuOH-F) fractions. The JGTE, fractions, and the isolated compounds were tested in vitro for their anthelmintic activity using two nematodes; one larval stage of cestode and one arthropod. Four major compounds were isolated from the most active fraction (BuOH-F) including two flavonoids and two secoirridoid glycosides, identified as kaempferol-3-O-neohesperoside (1), rutin (2), oleuropein (3), and ligstroside (4). RESULTS: Among the isolated compounds from most active fraction (BuOH-F), rutin (2) displayed the highest anthelmintic activity in a dose-dependent activity with IC50 of 41.04 µg/mL against H. muscae adult worm, followed by ligstroside (4) with IC50 of 50.56 µg/mL. CONCLUSIONS: These findings could advocate the traditional use of J. grandiflorum L. and provide further insight into the anthelmintic activity of flavonoids.

SCANNING ELECTRON MICROSCOPIC CHANGES IN HABRONEMA MUSCAE AFTER IN VITRO EXPOSURE TO PLANT EXTRACT (VERBESINA ALTERNIFOLIA).

Scanning electron microscopy (SEM) was used to study the morphological alteration occurring in Habronema muscae adult female worms after in vitro exposure to different doses of Verbesina alternifolia oil extract. The half maximal lethal concentration (LC50) was reached 400 ppm after 24hrs, while LC100 was reached 600 ppm after 48hrs. Irreversible degenerative changes were recorded such as shrinking, detachment and distortion of the cuticle, cephalic and distal region. The cuticular surface had a wrinkled, corrugated appearance with longitudinal ridges and transverse thick folds. The lips and papillae were deformed and aggregated over each other. There is a direct relation between the level of the recorded degenerative changes and the increase in the dose and exposure time. In the same time no degen'erative changes were recorded in the control worm exposed to PBS till the end of the exposure period.

Efficacy of thiabendazole, mebendazole, levamisole and ivermectin against gullet worm, Gongylonema pulchrum: in vitro and in vivo studies.

In vitro and in vivo studies were conducted to evaluate the effects of thiabendazole, mebendazole, levamisole and ivermectin against Gongylonema pulchrum. For in vitro assays, third-stage larvae (L3) incubated with the drugs were administered orally to mice and the ability of larvae to invade the gastric mucosa of the animals was examined. After incubation, only those larvae treated with high concentrations of levamisole (1 and 10 microg/ml) were tightly coiled with intestines exhibiting morphological abnormalities. Good dose-response data for the drugs tested was observed at the time of worm recovery from mice, with no worms recovered at the two highest concentrations of levamisole. In vivo efficacy of the drugs against adult worms was evaluated in six groups of three rabbits, each of which was infected with 30 L3 of G. pulchrum and treated with thiabendazole at 100 mg/kg for 3 days, mebendazole at 70 mg/kg for 3 days, levamisole as a single dose of 8 mg/kg, and subcutaneously injected ivermectin as a single dose of 0.2 mg/kg or vehicles of the drugs (control) at 4 months post-infection. Necropsy 14 days after treatment revealed that levamisole, mebendazole and ivermectin reduced worm burdens by 63.2%, 22.8% and 25.8%, respectively, with no reductions in worms observed with thiabendazole. The surviving worms were principally found in the esophagus with the remainder distributed among the buccal mucosa, the tongue, and/or pharyngeal mucosa in all groups. A number of morphologically abnormal eggs were observed within the uterus and ovijector in female worms recovered from the thiabendazole-treated group. These findings suggest that levamisole exhibits in vivo efficacy against G. pulchrum infection and that the larval invasion tests using mice could be used to screen for anthelmintic susceptibility of nematodes.

Anthelmintic action of plant cysteine proteinases against the rodent stomach nematode, Protospirura muricola, in vitro and in vivo.

Cysteine proteinases from the fruit and latex of plants, including papaya, pineapple and fig, were previously shown to have a rapid detrimental effect, in vitro, against the rodent gastrointestinal nematodes, Heligmosomoides polygyrus (which is found in the anterior small intestine) and Trichuris muris (which resides in the caecum). Proteinases in the crude latex of papaya also showed anthelmintic efficacy against both nematodes in vivo. In this paper, we describe the in vitro and in vivo effects of these plant extracts against the rodent nematode, Protospirura muricola, which is found in the stomach. As in earlier work, all the plant cysteine proteinases examined, with the exception of actinidain from the juice of kiwi fruit, caused rapid loss of motility and digestion of the cuticle, leading to death of the nematode in vitro. In vivo, in contrast to the efficacy against H. polygyrus and T. muris, papaya latex only showed efficacy against P. muricola adult female worms when the stomach acidity had been neutralized prior to administration of papaya latex. Therefore, collectively, our studies have demonstrated that, with the appropriate formulation, plant cysteine proteinases have efficacy against nematodes residing throughout the rodent gastrointestinal tract.

Apparent inactivity of several antiparasitic compounds against the eyeworm Thelazia lacrymalis in equids.

Activity of 15 compounds, given alone or in mixtures [butamisole, cambendazole, caviphos, febantel (alone or with trichlorfon), fenbendazole, ivermectin, levamisole-piperazine, oxfendazole, oxibendazole, pyrantel pamoate (alone or with piperazine-carbon disulfide complex), thiabendazole (alone or with piperazine or with trichlorfon), tioxidazole, and trichlorfon], against Thelazia lacrymalis was evaluated in 102 equids. Determination of activity was based on comparison of infection rate in treated animals examined at necropsy with infection rate of dead equids in our contemporary surveys. None of the compounds appeared to be active against T lacrymalis.