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This work describes the evaluation the potentiating activity of antibiotics by campesterol (1) and its derivatives (2-11) against multiresistant strains of Staphylococcusaureus 10, Escherichia coli 06 and Pseudomonas aeruginosa 24 employing the microdilution test. When subjected to the in vitro potentiating activity bioassay, all compounds showed a potentiating effect associated with norfloxacin against E. coli and P. aeruginosa with a reduction in the MIC of the antibiotic of up to 75%. These compounds also reduced the MIC of gentamicin by 37% to 87% in S. aureus and E. coli. Additionally, molecular docking studies were conducted to gain a deeper understanding of the interactions between the appropriate proteins and the most effective compounds (2, 4, 9, and 10 against E. coli; 1, 2, 3, 5, 8, and 9 against S. aureus), including antibiotics. This paper registers for the first time the in vitro and in silico studies on the action of compounds 1-11 in antibiotic potentiation.

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Anxiety and epilepsy are common worldwide and represent a primary global health concern. Fisetin, a flavonoid isolated from Bauhinia pentandra, has a wide range of biological activities may be a promising alternative to combat diseases related to the central nervous system (CNS). The present study aimed to investigate the anxiolytic and anticonvulsant effects of fisetin on adult zebrafish. Furthermore, molecular docking simulations were performed to improve the results. Fisetin did not present toxicity and caused anxiolytic behavior and delayed seizures in animals. This effect may occur through serotonin neurotransmission at 5-HT3A and/or 5-HT3B receptors. Molecular docking simulations showed that fisetin interacts with the orthosteric site of the 5-HT3A receptor with strong H-bond interactions with the Trp156 residue, with a strong contribution from the catechol ring, a behavior similar to that of the antagonist co-crystallized inhibitor granisetron (CWB). Fisetin may be a promising alternative to combat diseases related to the central nervous system.

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In this study, twelve campesterol derivatives (2-13) were prepared by esterification reaction at the hydroxy group in C-3 and catalytic hydrogenation at the carbon-carbon double bond in C-5(6). All obtained compounds were characterized by IR, 1 H-NMR, 13 C-NMR, and MS spectra. Campesterol (1) and its derivatives (2-13) were evaluated in vitro against Staphylococcus aureus (ATCC 6538), Streptococcus mutans (ATCC 0046), Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), and Klebsiella pneumoniae (ATCC 10031) using the microdilution method. Among tested compounds, 4, 6, 9, 11, 12, and 13 displayed the best antibacterial activity. Moreover, to support the antibacterial activity experiments, the investigation of molecular interactions of more active compounds, and also compound 1 and neomycin, used as starting material and positive control, respectively, at the binding site of the target proteins was performed using molecular docking simulations. Four compounds (7, 9, 10 and 11) are herein described for the first time.

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Herein, we describe the antiproliferative effects of two natural dibenzo [b,f]oxepines, pacharin and bauhiniastatin-1, isolated from Bauhinia acuruana on a breast cancer cell line and the mode of action underlying the cytotoxicity. Both compounds were cytotoxic in a panel of six tumor lines analyzed by the MTT assay, and IC50 values ranged from 7.8 to 45.1 µM, including human breast adenocarcinoma (MCF-7) cells. In contrast, none of the compounds were cytotoxic on normal human peripheral blood mononuclear cells (IC50 > 100 µM). Human breast adenocarcinoma (MCF-7) cells treated with pacharin or bauhiniastatin-1 20 µM for 24 h presented a reduction in cell volume and intensification of chromatin condensation, DNA fragmentation, and apoptotic cells. These findings became more evident after 48 h of exposure. Antiapoptotic B-cell lymphoma-2 family members, such as myeloid cell leukemia-1 and B-cell lymphoma-extra large, are important targets in cancer cells since their overexpression confers resistance to cancer treatments. A significant reduction of the myeloid cell leukemia-1 protein levels in human breast adenocarcinoma (MCF-7) cells after 24 h of treatment with pacharin or bauhiniastatin-1 at 20 µM was observed, while the B-cell lymphoma-extra large protein content was reduced in bauhiniastatin-1-treated cells at 40 µM only. The cytotoxic effects of pacharin and bauhiniastatin-1 are likely linked to myeloid cell leukemia-1 inhibition, which leads to the apoptosis of breast adenocarcinoma cells.

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Thirteen fucosterol derivatives were prepared by structural modification at the hydroxyl group in C-3 and catalytic hydrogenation at the carbon-carbon double bond in C-5(6) and C-24(28). The structures of all compounds were established based on their spectral data (IR, MS, and NMR). Fucosterol (1) and its derivatives (2-12, and a mixture of 13a and 13b) were evaluated for their in vitro antibacterial activity against Klebsiella pneumoniae (ATCC 10031), Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), Streptococcus mutans (ATCC 0046) and Staphylococcus aureus using the microdilution method. Among them, 1, 8, 9, 10, and a mixture of 13a and 13b exhibited the best antibacterial activity. The derivative 7 was inactive against all bacterial strains evaluated (MIC ≥ 2.327 mM). In addition, the investigation of binding interactions of more active compounds (1, 8, 9, 10, and mixture of 13a and 13b) to appropriate proteins was performed using molecular docking. This paper registers for the first time the in silico studies on the antibacterial activity of compounds 1, 8, 9, 10, and mixture of 13a/13b, and the spectral data of compounds 4, 6, and 7.

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Diabetes mellitus is a chronic metabolic disorder that has been increasing drastically around the worldwide. It is important to emphasize that although many drugs are commercially available to treat diabetes, many of them have shown a number of adverse effects. Therefore, search for new antidiabetic agents is of great interest, and natural products, especially those obtained from plants sources, may be an alternative to available drugs. This study reports the in vivo and in silico evaluation of the hypoglycemic activity of fisetinidol. The conformational analysis confirmed that the fisetinidol compound possesses two valleys in the potential energy curve, showing a stable conformer on the global minimum of the PES defined by the dihedral angle θ (C6-C7-O-H) at 179.9°, whose energy is equal to zero. In addition, fisetinidol has shown promise in glycemic control and oxidative stress caused by hyperglycemia induced by high sucrose concentration, causing hypoglycemic and hepatoprotective effects in adult zebrafish. ADMET studies showed that fisetinidol has high passive permeability, low clearance and low toxic risk by ingestion, and computational studies demonstrated that fisetinidol complexes in the same region as metformin and α-acarbose, which constitutes a strong indication that fisetinidol has the same inhibitory mechanisms of α-acarbose and metformin.Communicated by Ramaswamy H. Sarma.

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Phytochemical investigation of the stems of B. pulchella led to the isolation of the known compounds identified as a mixture of taraxerone (1) and ß-amirenone (2), a mixture of sitosterol (3) and stigmasterol (4), 2-hydroxy-3,5-dimethoxybibenzyl (5), 3',4'-dihydroxyphenyl-chroman-7-ol (6), fisetinidol (7), epicatechin (8), guibourtinidol (9), vanillic acid (10), 6'-O-vanilloylisotachioside (11) and 6'-O-syringoylisotachioside (12). The structures of these compounds were elucidated on the basis of their NMR spectroscopic data. The antioxidant activity of compound 7 has been investigated using DPPH° and ABTS°+ assays and the results showed inhibition in the both models. The compounds 6, 7 and 9 showed strong alpha-glucosidase inhibitory activities, being more active than acarbose, the positive control. In addition, all the compounds were isolated from B. pulchella for the first time, and among them, compounds 11 and 12 have not been reported previously from this genus.

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Two steroids (1 and 2), two oxepin derivatives (3 and 4) and seven flavonoids (5-11) were isolated from the stems of Bauhinia pentandra. Their structures were elucidated on the basis of NMR spectroscopic data, and by comparison with data previously reported in the literature. The ethanol extract from the stems of B. pentandra and the compounds, 4, 5, 6, 7, 8 and 11 have been evaluated as acetylcholinesterase inhibitors, and among these, the compound 5 exhibited the strongest activity. In addition, all the isolated compounds are reported for the first time as constituents of B. pentandra.

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Leishmania amazonensis is a species causative of cutaneous and anergic diffuse cutaneous leishmaniasis, treatment-resistant form, in the New World. Plants essential oils exhibit great potential as microbicide agents. We described the composition of the essential oils of two plants native from Brazil, Myrcia ovata, with geranial and neral as major constituents, and Eremanthus erythropappus, with α-bisabolol. In vitro effects of these essential oils on L. amazonensis promastigotes growth and ultrastructure were analysed as well as their cytotoxicity to murine macrophages. Both oils were highly active with IC50/96 h of 8.69 and 9.53 µg/mL for M. ovata and E. erythropappus against promastigotes and caused ultrastructural alterations including mitochondrial enlargement. Cytotoxicity for murine macrophages varied with the oil concentrations. The IC50 low values of both M. ovata and E. erythropappus oils against L. amazonensis and their relative low cytotoxicity to mammal host cells support their potential use against cutaneous leishmaniasis.

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OBJECTIVES: Many species of theBauhinia genus have been widely used in folk medicine as analgesic, anti-inflammatory and antioxidant agents. (-)-Fisetinidol palmitate is a semi-syntetic flavonoid obtained from the ethanolic extract of the stem of Bauhinia pulchella. This study aimed to evaluate the antiresorptive effect of the semi-syntetic (-)-fisetinidol palmitate in ligature-induced periodontitis in rats. Also, it evaluated the mechanism of action of (-)-fisetinidol palmitate and its toxicity. DESIGN: Periodontitis was inducedvia a nylon thread ligature (3.0) around the second upper left molars. Rats were treated (oral gavage) once a day for 11 days with (-)-fisetinidol palmitate (0.01 or 0.1 mg/kg) or saline vehicle. RESULTS: (-)-Fisetinidol palmitate (0.1 mg/kg) reduced alveolar bone loss, increased bone alkaline phosphatase (BALP), superoxide dismutase (SOD), and catalase (CAT) activity; also, it decreased IL1-ß, IL-8/CINC-1, nitrite/nitrate levels and myeloperoxidase activity. (-)-Fisetinidol palmitate reduced the mRNA levels of IL1-ß, IL-6, RANK, and RANK-L, while it increased the OPG ones. No statistical differences (P > 0.05) were observed in the transaminases (ALT, AST) and Total Alkaline Phosphatase (TALP) levels among groups. (-)- CONCLUSIONS: Fisetinidol palmitate did not result in any signs of toxicity and had anti-resorptive effects in a pre-clinical trial of periodontitis, showing antioxidant activity with the involvement of the RANK/RANKL/OPG pathway.

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The essential oils obtained by hydrodistillation from fresh leaves of Vitex agnus-castus and Ocimum campechianum, and from fresh inflorescences of Ocimum carnosum were analysed by GC-FID and GC-MS. The major components of V. agnus-castus essential oil were identified as 1,8-cineole (47.9%), terpinyl α-acetate (11.6%), sabinene (11.2%) and caryophyllene oxide (9.7%), while in the O. campechianum essential oil were eugenol (72.1%), ß-elemene (6.8%), (E)-caryophyllene (6.4%) and bicyclogermacrene (5.2%). Linalool (79.0%), α-epi-cadinol (5.4%), terpinen-4-ol (3.2%) and 1,8-cineole (2.8%) were the major constituents in the O. carnosum essential oil. The essential oils were subsequently evaluated for their larvicidal and cytotoxic activities. Larval bioassay against Aedes aegypti of V. agnus-castus, O. campechianum and O. carnosum essential oils showed LC50 values of 97.55 ± 0.35, 81.45 ± 0.35 and 109.49 ± 0.35 µg/mL, respectively. The in vitro cytotoxic activities of the essential oils has been evaluated on breast adenocarcinoma (MCF-7), lung carcinoma (NCI-H292), pro-myelocytic leukemia (HL-60), and cervical adenocarcinoma (HEP-2) human cell lines, and pro-myelocytic leukemia cells lines (HL-60) were found to be the most sensitive to all the essential oils tested than the others. This is the first report on larvicidal and cytotoxic activities of these essential oils.

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The present work aimed to investigate the antioxidant, anti-inflammatory and wound healing potential of ethyl acetate fraction from Bauhinia ungulata L. (FABU) on in vitro and in vivo models. Wound healing assay using human lung adenocarcinoma A549 cell line was employed to evaluate the ability of FABU in modulating cell migration. In addition, a surgical wound model in C57BL/6 mice was used to study the healing potential of FABU incorporated into gel carbomer 940 (Carbopol®). Evaluation of lipid peroxidation, inflammatory and anti-inflammatory mediator gene expression, rate of wound closure, and histological analysis were done. FABU significantly reduced the gap area in in vitro wound healing assay, 24 h after treatment. In the animal model, FABU at 0.5% topically applied once-daily for 5 days to the surgical wounds significantly reduced the lesion area. Moreover, it significantly decreased the levels of lipid peroxidation in the lesions and decreased the relative gene expression levels of IL-1ß and TNF-α in the injured region. In conclusion, our study suggests that Bauhinia ungulata can effectively promote the wound healing, probably by regulating the inflammatory environment during the early stages of the process.

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ABSTRACT The organic extracts from stems, roots and leaves of Tephrosia egregia Sandwith, Fabaceae, provided a new flavone, 5-hydroxy-8-(1",2"-epoxy-3"-hydroxy-3"-methylbutyl)-7-methoxyflavone (1), in addition to eleven known compounds: pongaflavone (2), praecansone B (3), 12a-hydroxyrotenone (4), praecansone A, 2',6'-dimethoxy-4',5'-(2",2"-dimethyl)-pyranochalcone, pongachalcone, maackiain, β-sistosterol and its glucoside, p-cumaric acid and cinnamic acid. The structures of all compounds were established on the basis of spectroscopic methods, mainly 1D and 2D NMR and HRESIMS, involving comparison with literature data. Cytotoxicity of compounds 1-4 was evaluated against AGP-01 (cancerous ascitic fluid), HCT-116 (colon adenocarcinoma), HL-60 (leukemia), PC-3 (prostate carcinoma), SF-295 (glioblastoma) and SKMEL 28 (melanoma) cell lines.

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Vitex gardneriana Schauer (Lamiaceae) popularly known as "jaramataia", is a shrub commonly found in caatinga biome located in Northeast Brazil. In folk medicine, its leaves have been used as analgesic and anti-inflammatory agents. The chemical composition of the essential oil from leaves obtained by hydrodistillation was analyzed and identified by GC-MS and GC-FID and showing a total of 26 constituents (95.9%) being 2 monoterpenes (0.4%) and 24 sesquiterpenes (95.4%). The main constituents identified were cis-calamenene (29.7%), 6,9-guaiadiene (14.5%) and caryophyllene oxide (14.0%). The essential oil has been demonstrated high larvicidal activity against Aedes aegypti (LC50 = 28.0 µg/mL). In the evaluation of the bioassay with Artemia salina the essential oil showed LC50 = 98.11 µg/mL. In addition, the essential oil did not show cytotoxicity (IC50 > 2.50 mg/mL) by the hemolysis assay.

Vitex gardneriana Schauer (Lamiaceae) popularmente conocido como "jaramataia", es un arbusto que se encuentra comúnmente en el bioma de caatinga ubicado en el noreste de Brasil. En medicina popular, sus hojas se han utilizado como analgésicos y agentes antiinflamatorios. La composición química de los aceites esenciales de las hojas obtenidas por hidrodestilación fue analizada e identificada por GC-MS y GC-FID y mostrando un total de 26 constituyentes (95.9%) siendo 2 monoterpenos (0.4%) y 24 sesquiterpenos (95.4%). Los componentes principales fueron cis-calamenene (29.7%), 6,9-guaiadiene (14.5%) y caryophyllene oxide (14.0%). El aceite esencial ha demostrado una alta actividad larvicida contra Aedes aegypti (CL50 = 28.0 µg/mL). En la evaluación del bioensayo con Artemia salina, el aceite esencial demostró CL50 = 98.11 µg/mL. Además, el aceite esencial no mostró citotoxicidad (IC50 > 2.5 mg / mL) mediante el ensayo de hemólisis.

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ABSTRACT Phytochemical investigation of Bauhinia acuruana Moric., Fabaceae, resulted in the isolation of sixteen constituents, including two new compounds 2'-hydroxy-2,3,5-trimethoxybibenzyl (1), (2R,3S)-2-(3,4'-dihydroxyphenyl)-5-methoxy-6-methylchroman-3,7-diol (2), together with fourteen known ones (3-16). The structures of the compounds were established by spectroscopic analysis including HR-ESI-MS, 1D and 2D NMR data, followed by comparison with previously reported data from the literature. Compounds 1, 2, 6, 7, 8 and 9 were evaluated for their cytotoxicity, which turned out to be marginal in a panel of six human cancer cell lines.

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A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.

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ABSTRACT A new lactone, 7-epi-griffonilide (1), and six known compounds, 2, 3a - 3c, 4a and 4b, were isolated from the leaves of Bauhinia pentandra (Fabaceae). The structures elucidation of 1 and 2 were based on detailed 2D NMR techniques and spectral comparison with related compounds, leading to complete assignment of the 1H and 13C NMR spectra.

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A new bibenzyl, 2'-hydroxy-3,5-dimethoxy-4-methylbibenzyl (1) and four known compounds identified as 2'-hydroxy-3,5-dimethoxybibenzyl (2), liquiritigenin (3), guibourtinidol (4) and fisetinidol (5) were isolated from the roots of Bauhinia ungulata L. Phytochemical investigations of the stems of B. ungulata led to the isolation of the known compounds identified as liquiritigenin (3), guibourtinidol (4), fisetinidol (5), taraxerol (6), betulinic acid (7), taraxerone (8), glutinol (9), a mixture of sitosterol (10) and stigmasterol (11), pacharin (12), naringenin (13) and eriodictyol (14). The structures of these compounds were elucidated on the basis of their spectral data (IR, MS, 1D- and 2D-NMR). The cytotoxicity of the bibenzyl 1 has been evaluated against four human cancer cell lines, showing the IC50 values of 4.3 and 6.5 µg ml-1 against pro-myelocytic leukemia (HL-60) and cervical adenocarcinoma (HEP-2) cell lines, respectively. This article also registers for the first time the 13 C-NMR data of the known bibenzyl 2.

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In order to develop bioactive lithocholic acid derivatives, we prepared fifteen semi-synthetic compounds through modification at C-3 and/or C-24. The reactions showed yields ranging from 37% to 100%. The structures of all compounds obtained were identified on the basis of their spectral data (IR, MS, 1D- and 2D-NMR). The activity of lithocholic acid and derivatives was evaluated against the growth of Escherichia coli, Staphylococcus aureus, Bacillus cereus and Pseudomonas aeruginosa. The derivative 3α-formyloxy-5ß-cholan-24-oic acid (LA-06) showed the best activity, with MIC values of 0.0790 mM against E. coli (Ec 27) and B. cereus in both cases, and 0.0395 mM against S. aureus (ATCC 12692). Lithocholic acid and the derivatives with MIC⩽1.2 mM were evaluated on the susceptibility of some bacterial pathogens to the aminoglycoside antibiotics neomycin, amikacin and gentamicin was evaluated. There are no previously reported studies about these compounds as modifiers of the action of antibiotics or any other drugs.

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The leaves of Myrcia ovata, popularly known as "laranjinha do mato", are frequently used as an infusion in folk medicine. The essential oil obtained from these leaves is rich in citral, a mixture of neral and geranial isomers, known for its analgesic effect. Male Swiss mice (20-22 g) were tested in models of acute pain (acetic acid-induced abdominal writhing, tail flick, and formalin tests) and acute inflammation (paw oedema and air pouch tests) as well as in a model for evaluation of spontaneous motor performance (open-field test). The essential oil from M. ovata was administered orally at doses of 50-300 mg/kg. In addition, water, vehicle, morphine (5.01 mg/kg for evaluation of pain and motor performance), acetyl salicylic acid (200 mg/kg in the formalin test), and dexamethasone (2.25 mg/kg for evaluation of oedema formation, leukocyte extravasation, and quantification of cytokines) were administered. The essential oil showed a significant effect at doses of 200 and 300 mg/kg in the acute pain and acute inflammation tests. The effect of the essential oil was reduced by pretreatment with naloxone. The essential oil did not induce motor impairment. The extract was not toxic after oral administration (LD50 > 3000 mg/kg). These data provide initial evidence that the traditional use of M. ovata can be effective in reducing pain and inflammation.

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