In vitro activity of Schinus terebinthifolius extract and fractions against Sporothrix brasiliensis.

BACKGROUND: Sporothrix brasiliensis is the causative agent of zoonotic cases of sporotrichosis in Brazil and is associated with atypical and severe presentations in cats, dogs, and humans. Sporotrichosis treatment is usually time- and cost-consuming, sometimes with poor response and host toxicity. Schinus terebinthifolius has proven efficacy against bacteria and fungi of clinical interest. OBJECTIVE: To determine the in vitro activity of S. terebinthifolius against S. brasiliensis. METHODS: Five S. brasiliensis isolates and three reference strains were subjected to a hydroethanol extract derived from the leaves of S. terebinthifolius and its fractions. The minimal inhibitory concentration (MIC) was determined using the broth microdilution method according to the M38-A2 CLSI guidelines. Also, the fungicidal/fungistatic activity of the extract and fractions was studied. FINDINGS: The crude extract of S. terebinthifolius inhibited the growth of S. brasiliensis (MIC: 0.5-1.0 µg/mL), while the partitioned extracts dichloromethane, ethyl acetate, and butanol demonstrated growth inhibition at 8 µg/mL due to a fungistatic activity. MAIN CONCLUSIONS: Due to its in vitro efficacy against S. brasiliensis and its known pharmacological safety, S. terebinthifolius is a candidate to be tested using in vivo models of sporotrichosis.

In vitro activity of Schinus terebinthifolius extract and fractions against Sporothrix brasiliensis

BACKGROUND Sporothrix brasiliensis is the causative agent of zoonotic cases of sporotrichosis in Brazil and is associated with atypical and severe presentations in cats, dogs, and humans. Sporotrichosis treatment is usually time- and cost-consuming, sometimes with poor response and host toxicity. Schinus terebinthifolius has proven efficacy against bacteria and fungi of clinical interest. OBJECTIVE To determine the in vitro activity of S. terebinthifolius against S. brasiliensis. METHODS Five S. brasiliensis isolates and three reference strains were subjected to a hydroethanol extract derived from the leaves of S. terebinthifolius and its fractions. The minimal inhibitory concentration (MIC) was determined using the broth microdilution method according to the M38-A2 CLSI guidelines. Also, the fungicidal/fungistatic activity of the extract and fractions was studied. FINDINGS The crude extract of S. terebinthifolius inhibited the growth of S. brasiliensis (MIC: 0.5-1.0 µg/mL), while the partitioned extracts dichloromethane, ethyl acetate, and butanol demonstrated growth inhibition at 8 µg/mL due to a fungistatic activity. MAIN CONCLUSIONS Due to its in vitro efficacy against S. brasiliensis and its known pharmacological safety, S. terebinthifolius is a candidate to be tested using in vivo models of sporotrichosis.

Potential use of extract of the plant Schwartiza brasiliensis (choisy) bedell ex gir.-Cañas against the toxic effects of the venom of Bothrops jararaca or B. jararacussu.

Envenomation by snakes is a worldwide health public issue, and antivenoms are less efficient in neutralizing local toxic effects. Thus, more efficient therapies to treat patients deserve attention, and plants have been extensively tested. So, the aim of this work was to evaluate the effect of the aqueous fraction of the plant Schwartzia brasiliensis to inhibit some toxic activities of Bothrops jararaca or B. jararacussu venom. S. brasiliensis inhibited coagulant, hemolytic, proteolytic, hemorrhagic, edematogenic, and lethal activities of both venoms, regardless if plant was mixed together with venoms or injected after them as well as the route of administration (intravenous, oral or subcutaneous) of the plant. The S. brasiliensis extract showed no toxicity to mice or red blood cells. Thus, S. brasiliensis may be useful as an alternative treatment for snakebite envenomation and aid antivenom therapy to neutralize relevant toxic activities in patients bitten by Bothrops species.

Antiviral and Immunomodulatory Effects of Norantea brasiliensis Choisy on Dengue Virus-2.

BACKGROUND/AIMS: Severe dengue fever is a result of exacerbated immune responses and no specific treatments are available. We evaluated the antiviral and immunomodulatory effects of Norantea brasiliensis Choisy. METHODS: Human adherent monocytes infected in vitro with dengue virus (DENV)-2 were incubated with the crude ethanol extract from leaves (NB1) or 3 derived fractions: dichloromethane (NB3), ethyl acetate (NB5), and butanolic (NB6) partitions. The antiviral and immunomodulatory activities were determined by intracellular detection of DENV antigen within monocytes and by secreted NS1 viral protein and cytokines. RESULTS: The crude extract alone exhibited both antiviral activities (intracellular and secreted antigens) and all fractions derived from this extract modulated NS1 production. Regarding the immunomodulatory effect, among the secreted factors, TNF-α was inhibited by NB3 and NB6; IL-6 was inhibited by NB1, NB3, and NB6; IL-10 by NB1 and NB3; and IFN-α by NB6. The crude extract (NB1) presented the best antiviral effect, whereas the dichloromethane fraction (NB3) presented an immunomodulatory effect in the inflammatory and anti-inflammatory cytokines. CONCLUSION: During in vitro DENV infection, N. brasiliensis Choisy exerts both antiviral and immunomodulatory effects that are likely associated, considering that less viral load may lead to less immunostimulation.

Isolation of limonoids from seeds of Carapa guianensis Aublet (Meliaceae) by high-speed countercurrent chromatography.

INTRODUCTION: Limonoids are tetranortriterpenoids of considerable interest due to their structural varieties and biological activities, such as insecticidal, antibacterial, antifungal, antimalarial, anticancer and antiviral. They contain oxygen atoms that confer a moderate polarity and are responsible for the difficulties in their separation by traditional chromatographic methods. High-speed countercurrent chromatography (HSCCC) is a versatile liquid-liquid separation technique, in which the sample is distributed between two non-miscible phases to achieve separation. OBJECTIVE: To isolate limonoids from a complex Carapa guianensis seed extract by gradient elution HSCCC and to identify them by spectrometric and spectroscopic methods. METHODOLOGY: The hexane extract of Carapa guianensis squeezed seeds was prepared by Soxhlet extraction. From this extract, 800 mg were submitted to gradient mode HSCCC, using the solvent systems hexane:ethyl acetate:methanol:water 1:2:X:1, X = 1.5 (system A) and X = 1.75 (system B). The upper organic phase of the system A was used as stationary phase, and the lower aqueous phases of both systems as mobile phases. In this procedure, 165 fractions of 4 mL (660 mL) were collected. RESULTS: Six compounds were isolated. Spectrometric and spectroscopic analysis allowed the identification of the substances, as follows: methyl angolensate (28.7 mg), 7-deacetoxy-7-oxogedunin (17.9 mg), deacetylgedunin (3.7 mg), 6alpha-acetoxygedunin (40.1 mg), gedunin (21.0 mg), and andirobin (5.8 mg). CONCLUSION: The use of gradient mode in HSCCC was a good alternative, exploiting small variations of partition coefficient between the substances. Thus it was possible to isolate them in a good relative abundance, compared with classical chromatographic methods.