Schistosomiasis, caused by blood flukes of the genus Schistosoma, still imposes a considerable public health burden on large parts of the world. The control of this disease depends almost exclusively on the drug praziquantel, and there are no alternative drugs in sight. Natural compounds have recently attracted significant attention due to their relevance to parasitic infection and potential development into new therapeutic agents. Epiisopiloturine is an imidazole alkaloid isolated from the leaves of Pilocarpus microphyllus (Rutaceae), a native plant from Brazil. Here, we report the in vitro effect of this drug on the survival time of Schistosoma mansoni of different ages, such as 3 h old and 1, 3, 5, and 7 days old schistosomula, 49-day-old adults, and on egg output by adult worms. Epiisopiloturine at a concentration of 300 μg/mL caused the death of all schistosomula within 120 h. Extensive tegumental alterations and death were observed when adult schistosomes had been exposed to 150 μg/mL of the epiisopiloturine. At the highest sub-lethal dose of alkaloid (100 μg/mL), a 100% reduction in egg laying of paired adult worms was observed. Additionally, epiisopiloturine showed selective antischistosomal activity and exhibited no cytotoxicity to mammalian cells. This report provides the first evidence that epiisopiloturine is able to kill S. mansoni of different ages and inhibit worm egg laying.

α-PHE has an antinociceptive effect and it possibly involves the glutamatergic, opioid, nitrergic, cholinergic and adrenergic systems.

This paper presents an industrial scale process for extraction, purification, and isolation of epiisopiloturine (EPI) (2(3H)-Furanone,dihydro-3-(hydroxyphenylmethyl)-4-[(1-methyl-1H-imidazol-4-yl)methyl]-, [3S-[3a(R*),4b]]), which is an alkaloid from jaborandi leaves (Pilocarpus microphyllus Stapf). Additionally for the first time a set of structural and spectroscopic techniques were used to characterize this alkaloid. EPI has shown schistomicidal activity against adults and young forms, as well as the reduction of the egg laying adult worms and low toxicity to mammalian cells (in vitro). At first, the extraction of EPI was done with toluene and methylene chloride to obtain a solution that was alkalinized with ammonium carbonate. The remaining solution was treated in sequence by acidification, filtration and alkalinization. These industrial procedures are necessary in order to remove impurities and subsequent application of the high performance liquid chromatography (HPLC). The HPLC was employed also to remove other alkaloids, to obtain EPI purity higher than 98%. The viability of the method was confirmed through HPLC and electrospray mass spectrometry, that yielded a pseudo molecular ion of m/z equal to 287.1 Da. EPI structure was characterized by single crystal X-ray diffraction (XRD), 1H and 13C nuclear magnetic resonance (NMR) in deuterated methanol/chloroform solution, vibrational spectroscopy and mass coupled thermal analyses. EPI molecule presents a parallel alignment of the benzene and the methyl imidazol ring separated by an interplanar spacing of 3.758 Å indicating a π-π bond interaction. The imidazole alkaloid melts at 225°C and decomposes above 230°C under air. EPI structure was used in theoretical Density Functional Theory calculations, considering the single crystal XRD data in order to simulate the NMR, infrared and Raman spectra of the molecule, and performs the signals attribution.

Cattle tick control has been limited by the resistance of these parasites to synthetic acaricides. Natural products are a possible alternative as they have different mechanisms of action. Acmella oleracea is a native plant with a large cultivated area in the Amazon region and could be easily used for large-scale preparation of a commercial product. This study evaluated the in vitro action of the hexane extract of the aerial parts of A. oleracea on larvae and engorged females of the cattle tick Rhipicephalus microplus. Spilanthol was the major constituent with a content of 14.8% in the extract. The hexane extract of A. oleracea was highly effective against larvae of R. microplus with an LC50 of 0.8 mg mL(-1). Against engorged females, hexane extract of A. oleracea reduced oviposition and hatchability of eggs with an LC50 of 79.7 mg mL(-1). Larvae and engorged females were killed by the hexane extract with high efficiency (>95%) at concentrations of 3.1 and 150.0 mg mL(-1), respectively. These results demonstrate that the hexane extract of A. oleracea has significant activity against R. microplus and has potential to be developed into formulations for tick control.

Pilocarpus microphyllus Stapf ex Wardlew (Rutaceae), popularly known as jaborandi, is a plant native to the northern and northeastern macroregions of Brazil. Several alkaloids from this species have been isolated. There are few reports of antibacterial and anthelmintic activities for these compounds. In this work, we report the antibacterial and anthelmintic activity of five alkaloids found in P. microphyllus leaves, namely, pilosine, epiisopilosine, isopilosine, epiisopiloturine and macaubine. Of these, only anthelmintic activity of one of the compounds has been previously reported. Nuclear magnetic resonance, HPLC and mass spectrometry were combined and used to identify and confirm the structure of the five compounds. As regards the anthelmintic activity, the alkaloids were studied using in vitro assays to evaluate survival time and damaged teguments for Schistosoma mansoni adult worms. We found epiisopilosine to have anthelmintic activity at very low concentrations (3.125 μg mL ); at this concentration, it prevented mating, oviposition, reducing motor activity and altered the tegument of these worms. In contrast, none of the alkaloids showed antibacterial activity. Additionally, alkaloids displayed no cytotoxic effect on vero cells. The potent anthelmintic activity of epiisopilosine indicates the potential of this natural compound as an antiparasitic agent. Copyright © 2017 John Wiley & Sons, Ltd.

Schistosomiasis is a serious disease currently estimated to affect more that 207 million people worldwide. Due to the intensive use of praziquantel, there is increasing concern about the development of drug-resistant strains. Therefore, it is necessary to search for and investigate new potential schistosomicidal compounds. This work reports the in vivo effect of the alkaloid epiisopiloturine (EPI) against adults and juvenile worms of Schistosoma mansoni. EPI was first purified its thermal behavior and theoretical solubility parameters charaterised. In the experiment, mice were treated with EPI over the 21 days post-infection with the doses of 40 and 200 mg/kg, and 45 days post-infection with single doses of 40, 100 and 300 mg/kg. The treatment with EPI at 40 mg/kg was more effective in adult worms when compared with doses of 100 and 300 mg/kg. The treatment with 40 mg/kg in adult worms reduced parasite burden significantly, lead to reduction in hepatosplenomegaly, reduced the egg burden in faeces, and decreased granuloma diameter. Scanning electron microscopy revealed morphological changes to the parasite tegument after treatment, including the loss of important features. Additionally, the in vivo treatment against juvenile with 40 mg/kg showed a reduction of the total worm burden of 50.2%. Histopathological studies were performed on liver, spleen, lung, kidney and brain and EPI was shown to have a DL50 of 8000 mg/kg. Therefore EPI shows potential to be used in schistosomiasis treatment. This is the first time that schistosomicidal in vivo activity of EPI has been reported.

Neem leaf ethanolic extract presented inhibitory effect on MRSA biofilm and planktonic aggregation formation, and anthelmintic activity against S. mansoni worms.

These results indicate the antinociceptive effect of Lecythis pisonis leaves and suggest that this effect may be related to opioid pathway, K+ATP channels, and L-arginine-nitric oxide modulation. Furthermore, these data support the ethnomedical use of this plant.