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-1ß 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 ±â€¯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-1ß (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.

Characterization of the Antidiabetic Role of Parkinsonia aculeata (Caesalpineaceae).

This paper reports the characterization of the antidiabetic role of a hydroethanolic extract from Parkinsonia aerial parts (HEPA), in normal and alloxan-induced diabetic rats, treated with HEPA (125 and 250 mg/kg; p.o.). Oral glucose tolerance test, acute oral toxicity test and preliminary phytochemical analyses were performed. The diabetic rats treated with HEPA showed a significant reduction in serum and urinary glucose, urinary urea and triglyceride levels, as compared to the diabetic untreated group. However, in the normal treated groups, a significant reduction was found only in serum triglyceride levels. In all treated diabetic groups, an improvement in hepatic glycogen was observed, as well as a decrease in liquid intake and urinary volume, and an enhancement in the weight of skeletal muscles (soleus and extensor digitorum longus), kidneys and epididymal adipose tissue. Nevertheless, body and liver weights were ameliorated only in the diabetic group treated with HEPA (250 mg/kg). Moreover, oral glucose tolerance was higher in animals treated with HEPA, while results also showed that HEPA could be considered toxicologically safe. Phytochemical analysis revealed the presence of tanins, flavonoids and steroids in HEPA. In conclusion, P. aculeata presents an antidiabetic activity and other beneficial effects that ameliorate diabetes and associated complications.

Antimicrobial Activity of Indigofera suffruticosa.

Various organic and aqueous extracts of leaves of Indigofera suffruticosa Mill (Fabaceae) obtained by infusion and maceration were screened for their antibacterial and antifungal activities. The extracts were tested against 5 different species of human pathogenic bacteria and 17 fungal strains by the agar-solid diffusion method. Most of the extracts were devoid of antifungal and antibacterial activities, except the aqueous extract of leaves of I. suffruticosa obtained by infusion, which showed strong inhibitory activity against the Gram-positive bacteria Staphylococcus aureus with a minimal inhibitory concentration (MIC) of 5000 microg ml(-1). The MIC values to dermatophyte strains were 2500 microg ml(-1) against Trichophyton rubrum (LM-09, LM-13) and Microsporum canis. This study suggests that aqueous extracts of leaves of I. suffruticosa obtained by infusion can be used in the treatment of skin diseases caused by dermatophytes.

Embryotoxicity in vitro with extract of Indigofera suffruticosa leaves.

Aqueous extract of leaves of Indigofera suffruticosa (AELIs) were studied for adverse effects in preimplantation mouse embryos. Two-cell mouse embryos were cultured for 94 h in human tubal fluid medium (HTF), and AELIs at a concentration of 5 or 10 mg/ml. On Day 4 of culture, morulae and blastocysts were collected for morphological analysis of blastomeres. We found that embryos exposed to the higher concentration of AELIs (10 mg/ml) did not develop and all embryos persisted at the two-cell stage. Those embryos exposed to the lower concentration (5 mg/ml) showed development until morula, blastocyst and hatched blastocyst stages that were similar to the controls. These results suggest that use of AELIs may be hazardous to humans who make use of it in folk medicine.