Cytotoxicity, antifungal and antioxidant activities of the essential oil from Eupatorium ballotifolium Kunth (Asteraceae)

Chemical Characterization of Corydalis chaerophylla D.C. Extracts and Preliminary Evaluation of Their in Vitro and in Vivo Biological Properties

Genus Corydalis is a rich source of isoquinoline alkaloids reported to having potential bioactivities. Corydalis chaerophylla collected from Nepal at an altitude of 2400-4800 m was extracted using hexane, methanol and chloroform as solvents. The resulting hexane, methanol and chloroform extracts were subjected to LC-DAD-MSn analysis to yield fifteen different alkaloids. To assess any potential pharmacological properties, antimicrobial activity against two Gram-positive, two Gram-negative bacterial strains and one fungal strain was assessed, revealing significant inhibitive action of the methanol and chloroform extracts. Of the extracts obtained using chloroform contained the highest content of phenolic compounds at 113 mg GAE/g, while the highest total flavonoid content was found for the hexane extract with a value of 46.45 mg QE/g. The chloroform extract also exhibited a considerable antioxidant activity at IC50 value, 261.5±3 μg/mL, for the DPPH assay. Conversely, the methanol extract exhibited the highest LC50 value for Brine Shrimp cytotoxicity at 196±3 μg/mL being least potential for the test. The methanol extract was found to be the most active against α-amylase inhibition with an IC50 of 51.52±2 μg/mL. In an in vivo acute oral toxicity study against mice, methanol and chloroform extracts presented harmful effects with 1000.36 mg/kg BW and 515 mg/kg BW for LD50 , respectively. By analyzing all the results of the solvents used, the chloroform extract was found to be the most active, a feature that will be used in future isolation procedures and other pharmacological tests.

The essential oil of the leaves of Verbesina macrophylla (Cass.) S.F.Blake has antimicrobial, anti-inflammatory and antipyretic activities and is toxicologically safe

ETHNOPHARMACOLOGICAL RELEVANCE

Verbesina macrophylla (Cass.) S.F.Blake is a medicinal plant from South America, popularly known as "asa de peixe", "asa de peixe branco", "cambará branco" or "cambará guaçu", being used by traditional communities for its healing powers in the form of teas, infusions, liqueurs and extracts, for the treatment of bacterial and fungal infections of the urinary and respiratory tracts, such as kidney problems, bronchitis, inflammation and fever. However, none of the ethnopharmacological properties has been scientifically evaluated.

AIM OF THE STUDY

Based on the ethnopharmacological use of the species, this study investigated the chemical composition, and for the first time acute toxicity, hemolytic, antimicrobial, anti-inflammatory and antipyretic activities of the essential oil from leaves of V. macrophylla.

MATERIAL AND METHODS

The essential oil was obtained from the leaves by hydrodistillation (HD), being characterized by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography coupled to flame ionization detection (GC-FID). The antimicrobial activity was evaluated by the broth microdilution technique in bacteria and fungi that cause infections of the respiratory and urinary tract, and toxicological safety regarding hemolytic activity on human red blood cells (hRBCs), and acute toxicity in mice. The anti-inflammatory activity was evaluated by the model carrageenan-induced peritonitis with quantification of the levels of TNF-α and IL-1β in the intraperitoneal fluid, and ear edema induced by croton oil. The antipyretic activity evaluated in mice with pyrexia induced by yeast.

RESULTS

The extraction of essential oil by hydrodistillation (HD) showed a yield of 0.33 ± 0.04%, with its composition constituted mainly by sesquiterpenes of hydrocarbons (94.00%). The essential oil demonstrated antibacterial and antifungal activity, with a low rate of hemolysis in human red blood cells (hRBCs) and no clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD₅₀ is greater than 5000 mg/kg; p.o. The essential oil demonstrated anti-inflammatory activity reducing levels of pro-inflammatory cytokines TNF-α (38.83%, 72.42% and 73.52%) and IL-1β (37.70%, 75.92% and 87.71%), and ear edema by 49.53%, 85.04% and 94.39% at concentrations of 4, 40 and 400 mg/kg, respectively. The antipyretic activity presented by the essential oil is statistically similar to dipyrone.

CONCLUSION

The set of results obtained, validates the main activities attributed to the traditional use of Verbesina macrophylla (Cass.) S.F.Blake. These data add industrial value to the species, considering that the antimicrobial, anti-inflammatory and antipyretic activities present results similar to the drugs already used also presenting safety. The results suggest that essential oil from V. macrophylla may be used by industry for the development of drugs with natural antimicrobial, anti-inflammatory and antipyretic effect.

Larvicidal Evaluation against Aedes aegypti and Antioxidant and Cytotoxic Potential of the Essential Oil of Tridax procumbens L. Leaves

The present study evaluated the antioxidant, cytotoxic, and larvicidal potential of the essential oil of Tridax procumbens leaves, as well as identified the compounds present in the essential oil. The antioxidant activity was evaluated by the sequestration method of 2,2-diphenyl-1-picrylhydrazyl radical, the cytotoxic activity was evaluated using Artemia salina, the larvicidal bioassay was performed with larvae in the third stage of development of the Aedes aegypti mosquito, and the identification of the metabolites was performed by gas chromatography coupled to the mass spectrometer (GC-MS). The phytochemical oil analysis showed the presence of 20 compounds, with thymol and γ-terpinene being the main ones. It presented antioxidant activity with an IC50 of 194.51 μg mL-1, demonstrating antioxidant activity in the highest concentrations tested. It presented low cytotoxic activity against A. salina, with an LC50 of 1238.67 μg mL-1, demonstrating atoxicity in the concentrations tested. The essential oil presented good larvicidal activity when compared to the literature, with an LC50 = 79.0 μg mL-1 in 24 hours and LC50 of 69.15 μg mL-1 in 48 hours. In this way, it was possible to identify that the essential oil of the leaves of T. procumbens presented potential for the development of a natural larvicide, as well as antioxidant activity satisfactory to the radical DPPH and low toxicity to A. salina.

Gastroprotective activity and pharmacological safety evaluation of Eupatorium aschenbornianum

Eupatorium aschenbornianum has been widely used in traditional Mexican and folk medicine for the treatment of wounds, skin lesions, hemorrhages and gastric ulcers in humans. Phytochemical studies have indicated that hexane extracts of E. aschenbornianum have anti-microbial and anti-fungal activities. In the present study, an accurate and reliable approach using a murine model was pursued to evaluate the anti-ulcer activity, lipid peroxidation properties and acute toxicity of powdered dried stem of E. aschenbornianum. The results indicated that administration of E. aschenbornianum exerted an anti-ulcerative effect and decreased lipid peroxidation in gastric ulcers induced by acetylsalicylic acid. An acute toxicity assay indicated normal behavior and no significant variations in the weight and food consumption of animals. In addition, quantitative analysis of biochemical parameters did not indicate any liver or kidney damage. The results indicated that E. aschenbornianum may be a safe therapeutic agent for the prevention of gastric ulcers.

Circadian Rhythm, and Antimicrobial and Anticholinesterase Activities of Essential Oils from Vitex gardneriana

Vitex gardneriana, popularly known as “jaramataia”, is a shrub commonly found in the caatinga biome located in northeast Brazil. In folk medicine, its leaves have been used as analgesic and anti-inflammatory agents. Here we describe, for the first time, the chemical composition of the leaf essential oils extracted at 8.00, 12.00 and 17.00 h from V. gardneriana and report on their circadian rhythm, and antimicrobial and anticholinesterase activities. The essential oils’ antifungal activity was evaluated by a broth microdilution method using strains of dermatophytes, fungi and yeasts. The modulatory activity assays were performed by the checkerboard technique using ketoconazole as a standard drug, and acetylcholinesterase inhibitory activity was performed using Ellman's colorimetric method and compared with a reference acetycholinesterase inhibitor (physostigmine). The essential oils extracted from the leaves were analyzed by GC/MS and GC/FID. Twenty-five constituents (94.7%) were identified in the 8 o'clock oil, these being 2 monoterpenes (0.4%) and 23 sesquiterpenes (94.3%). For the essential oil extracted at 12 o'clock, 26 constituents (91.8%) were identified, of which 2 were monoterpenes (0.3%) and 24 sesquiterpenes (91.5%). For the essential oil extracted at 17.00 h, 32 constituents (91.4%) were identified, of which 5 were monoterpenes (3.4%) and 27 sesquiterpenes (88%). The main constituents of the 8.00, 12.00 and 17.00 h essential oils were the sesquiterpenes cis-calamenene (27.9, 24.5 and 25.8%), 6,9-guaiadiene (21.8, 11.2 and 18.4%) and caryophyllene oxide (16.7, 26.3 and 13.8%), respectively. The essential oils showed activity against strains of Trichophyton rubrum.