Dichloromethane and aqueous fractions from leaves and stems of Piper arboreum Aubl., P. aduncum L., P. amalago L., P. crassinervium H.B. & K., P. diospyrifolium Kunth, P. hispidum Sw. and P. xylosteoides (Kunth) Steud. were tested against adult worms of Schistosoma mansoni. The in vitro activity was evaluated in terms of mortality, number of separated worms and number of worms with reduced motor activity. Most dichloromethane fractions from all Piper species showed moderate schistosomicidal activity, but aqueous fractions were not active. The dichloromethane fraction of P. amalago leaves (at 100 μg/ml) showed the highest activity, resulting in worm mortality, the separation of worm pairs and reduced motor activity. Chromatographic fractionation of the dichloromethane fraction of P. amalago leaves led to the isolation of its major compound, which was also tested against adults of S. mansoni. The isolated piperamide N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl] pyrrolidine, at 100 μ m, resulted in the mortality of all adult worms after 24 h of incubation. The findings suggest that species of Piper are potential sources of schistosomicidal compounds.
Alicyclobacillus acidoterrestris is a gram-positive aerobic bacterium. This bacterium resists pasteurization temperatures and low pH and is usually involved in the spoilage of juices and acidic drinks. The objective of this study was to evaluate the antibacterial activities of nisin and the species Piper (Piperaceae) on A. acidoterrestris. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined by the broth microdilution method. The species Piper aduncum had the lowest MIC and an MBC of 15.6 μg/mL and was selected for fractionation. Six fractions were obtained, and the dichloromethane fraction (F.3) had the lowest MIC/MBC (7.81 μg/mL). The dichloromethane fraction was again fractionized, and a spectral analysis revealed that the compound was prenylated chromene (F.3.7). The checkerboard method demonstrated that the crude extract (CE) of P. aduncum plus nisin had a synergistic interaction (fractional inhibitory concentration [FIC] = 0.24). The bactericidal activity of (F.3.7) was confirmed by the time-kill curve. P. aduncum, nisin, and prenylated chromene exhibited strong antibacterial activity against the spores and vegetative cells of A. acidoterrestris. The results of this study suggest that extracts of the genus Piper may provide an alternative to the use of thermal processing for controlling A. spoilage.
Supercritical fluid extraction was used to extract the alkaloid N-[7-(3′,4′-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl]pyrrolidine from leaves of Piper amalago L. A three-level orthogonal array design matrix, OAD OA9(34), was used for optimization of the parameters of supercritical extraction of the alkaloid, employing supercritical carbon dioxide: extraction time (20, 40, and 60 min), temperature (40, 50, and 60°C), pressure (150, 200, and 250 bar), and the use of cosolvents (ethanol, methanol, and propyleneglycol). All parameters had significant effect on the alkaloid yield. The alkaloid yield after 60 min of extraction without cosolvents at 9 different conditions (32) in terms of temperature (40, 50, and 60°C) and pressure (150, 200, and 250 bar) was also evaluated. The optimal yield (≈3.8 mg g−1) was obtained with supercritical CO2 + methanol (5% v : v) at 40°C and 200 bar for 60 min of extraction.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.