Triterpene acids (ursolic, oleanoic, gypsogenic, and sumaresinolic acids) isolated from Miconia species, along with a mixture of ursolic and oleanolic acids and a mixture of maslinic and 2-α-hydroxyursolic acids, as well as ursolic acid derivatives were evaluated against the following microorganisms: Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, Streptococcus salivarius, Streptococcus sobrinus, and Enterococcus faecalis, which are potentially responsible for the formation of dental caries in humans. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) during the evaluation of the antibacterial activity. All the isolated compounds, mixtures, and semi-synthetic derivatives displayed activity against all the tested bacteria, showing that they are promising antiplaque and anticaries agents. Ursolic and oleanolic acids displayed the most intense antibacterial effect, with MIC values ranging from 30 μg/mL to 80 μg/mL. The MIC values of ursolic acid derivatives, as well as those obtained for the mixture of ursolic and oleanolic acids showed that these compounds do not have higher antibacterial activity when compared with the activity observed with either ursolic acid or oleanolic acid alone. With regard to the structure-activity relationship of triterpene acids and derivatives, it is suggested that both hydroxy and carboxy groups present in the triterpenes are important for their antibacterial activity against oral pathogens.

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The efficacy of Licochalcone A (LicoA) and its two analogs were reported against Leishmania (Leishmania) amazonensis and Leishmania (Leishmania) infantum in vitro, and in experimental model of L. (L.) infantum in vitro. Initially, LicoA and its analogs were screened against promastigote forms of L. (L.) amazonensis. LicoA was the most active compound, with IC50 values of 20.26 and 3.88 μM at 24 and 48 h, respectively. Against amastigote forms, the IC50 value of LicoA was 36.84 μM at 48 h. In the next step, the effectivity of LicoA was evaluated in vitro against promastigote and amastigote forms of L. (L.) infantum. Results demonstrated that LicoA exhibited leishmanicidal activity in vitro against promastigote forms with IC50 values of 41.10 and 12.47 μM at 24 and 48 h, respectively; against amastigote forms the IC50 value was 29.58 μM at 48 h. Assessment of cytotoxicity demonstrated that LicoA exhibited moderate mammalian cytotoxicity against peritoneal murine macrophages; the CC50 value was 123.21 μM at 48 h and showed about 30% of hemolytic activity at concentration of 400 μM. L. (L.) infantum-infected hamsters and treated with LicoA at 50 mg/kg for eight consecutive days was able to significantly reduce the parasite burden in both liver and spleen in 43.67 and 39.81%, respectively, when compared with negative control group. These findings suggest that chalcone-type flavonoids can be a promising class of natural products to be considered in the search of new, safe, and effective compounds capable to treat canine visceral leishmaniosis (CVL).

Chemical investigation of the EtOAc fraction (EF) obtained from the ethanolic extract of Zanthoxylum naranjillo (Rutaceae) leaves (EE) by preparative HPLC resulted in the isolation of protocatechuic acid (1), gallic acid (2), p-hydroxybenzoic acid (3), and 5-Ocaffeoylshikimic acid (4). This is the fi rst time that the presence of compounds 1 -4 in Z. naranjillo has been reported. Compounds 1 -4, the EE, and EF were tested in vitro against Schistosoma mansoni adult worms. The results showed that the S. mansoni daily egg production decreased by 29.8%, 13.5%, 28.4%, 17.7%, 16.3%, and 6.4%, respectively. Compounds 1 and 3 were also able to separate adult worm pairs into male and female. This activity may be correlated with the reduction in egg production, since 1 and 3 showed better inhibitory properties compared with 2 and 4.

Protective Effect of a-and b-amyrin, a Triterpene Mixture From Protium heptaphyllum (Aubl.) March. Trunk Wood Resin, Against Acetaminophen-Induced Liver Injury in Mice. Effect of a-, b-amyrins From Protium heptaphyllum: Role of Capsaicinsensitive Primary Afferent Neurons. Planta Med., 70, 780-782 (2004). AbstractInitially, the seeds of Baccharis dracunculifolia were collected from populations of 10 different regions, and the cultivation experiment was carried out in an experimental area of 1,800 m 2 by cultivating 100 individuals of each Downloaded by [Dalhousie University]