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Hippeastrum elegans is a Brazilian Amaryllidaceae plant producing galantamine (GAL), an anticholinesterase drug for Alzheimer's disease, besides other alkaloids such as pseudolycorine (PSE), narciclasine (NAR) and sanguinine (SAN). Therefore, we used a metabolomic approach to investigate the influence of the harvest time on its chemical composition and acetylcholinesterase activity (AChE). Alkaloid extracts were analyzed by UPLC-ESI-MS and 1H NMR, then assessed for AChE inhibitory activity. These data were combined and analyzed by Partial Least Square (PLS) regression. H. elegans was found to be rich in PSE and NAR, achieving higher contents in 270 and 390 days of cultivation, respectively. However, the highest anti-AChE activities were observed for 450 days-bulbs extracts. PLS indicated pseudolycorine as the discriminant compound for this extract, hence responsible for its higher anti-AChE activity jointly with the known AChE inhibitors GAL and SAN. Thus, the cultivation of H. elegans appears to be a promising way for providing bioactive alkaloids.

Vigna unguiculata is an important source of proteins and energy for humans and animals. However, postharvest losses caused by Callosobruchus maculatus can reach from 20 to 100% of stored seeds. In this study, the insecticide potential of compounds extracted from Himatanthus drasticus latex was assessed. The latex was extracted with ethanol (70%) and then partitioned through sequential use of hexane and chloroform. These fractions were investigated by chromatography to determine their chemical composition. Plumieride, identified in a hydroalcoholic subfraction, was tested for insecticidal activity against C. maculatus. The ethanolic fraction (LC50 = 0.109; LC90 = 0.106%) and the plumieride (LC50 = 0.166; LC90 = 0.167%) were lethal to larvae. Plumieride (0.25%) delayed larval development, and mortality reached 100%. Its inhibitory action on intestinal α-amylase from larvae was higher (89.12%) than that of acarbose (63.82%). Plumieride (0.1%) inhibited the enzyme α-amylase in vivo in the larval intestine. This result was confirmed by a zymogram test performed by SDS-PAGE when the enzyme electrophoresed on gel copolymerized with starch. When spread on seeds, the hydroalcoholic fraction (1.0%) reduced infestation. The loss of seed mass was 5.26% compared to the control (44.97%). The results confirm the effect of latex compounds in protecting stored seeds against weevil infestation.

Neste estudo propõe-se avaliar os efeitos toxicológicos, pressóricos e renais da onco-A em modelos animais in vivo e ex vivo. A Oncocalyxona A (onco-A) isolada de Auxemma oncocalyx foi estudada nas doses 1, 3, e 10 µg/mL. Utilizou-se camundongos Swiss fêmeas (20-25g) para o teste de toxicidade oral aguda. Os dados foram comparados por teste t de Student, Two-Way ANOVA e pós-teste de Bonferroni (p

Two new diterpenoid derivatives 7α,12β,17-triacetoxy-6β,19-dihydroxy-13β,16-spirocicloabiet-8-ene-11,14-dione (1) and 6β-acetoxy-3β,7α,12α-trihydroxy-13β,16-spirocicloabiet-8-ene-11,14-dione (2) along with 11 (3–13) miscellaneous compounds were isolated from the leaves of Plectranthus ornatus Codd. Their structures were elucidated by spectroscopic analysis and gauge independent atomic orbitals 13C NMR calculations. The isolated compounds were screened for their effects on intestinal motility using guinea-pig ileum and duodenum and by their cytotoxicity against 4 human cancer cell lines (HCT-116, SF-295, PC-3, and HL-60). Compounds 6 and 9 were moderately cytotoxic against HL-60, whereas 6 and 13 were more active on SF-295 and HCT-116.

To fight against cancer, smarter drugs and drug delivery systems are required both to boost the efficiency of current treatments while reducing deleterious side effects, and combine diagnosis/monitoring with therapy (theranosis) in the search for the final goal of personalized medicine. This work presents the design, preparation, and proof-of-principle validation of a novel hybrid organic-inorganic nanocomposite joining together non-invasive imaging capabilities through magnetic resonance imaging and externally actuated therapeutic properties through a combination of chemo- and thermotherapy. The lipidic matrix of the nanocomposite was composed of carnauba wax, which was simultaneously dual loaded with magnetite nanoparticles and the anticancer drug Oncocalyxone A. Obtained formulations were fully characterized and showed outstanding performances as T2 -contrast agents in magnetic resonance imaging (r2 >800 mm-1 s-1 ), heat generating sources in magnetic hyperthermia (specific absorption rate, SAR>200 W g-1 Fe ), and magnetically responsive drug delivery vehicles. The potential of the designed formulations as theranostic agents was validated in vitro and results indicated a synergistic thermo/chemotherapeutic effect derived from heat generation and controlled drug delivery to cancer growth. Thereby, this external control over the drug delivery profile and the integrated imaging capability open the door to personalized cancer medicine and real-time monitoring of tumor progression.

Some first-line cytotoxic chemotherapics, e.g. doxorubicin, paclitaxel and oxaliplatin, induce activation of the immune system through immunogenic cell death (ICD). Tumor cells undergoing ICD function as a vaccine, releasing damage-associated molecular patterns (DAMPs), which act as adjuvants, and neoantigens of the tumor are recognized as antigens. ICD induction is rare, however it yields better and long-lasting antitumor responses to chemotherapy. Advanced metastatic melanoma (AMM) is incurable for more than half of patients. The discovery of ICD inducers against AMM is an interesting drug discovery strategy with high translational potential. Here we evaluated ICD induction of four highly cytotoxic chromomycins A (CA5-8). B16-F10, a metastatic melanoma cell line, treated with CA5-8 and doxorubicin exhibited ICD features such as autophagy and apoptosis, externalization of calreticulin, and releasing of HMGB1. However, CA5-treated cells had the best profile, also inducing ATP release, ERp57 externalization, phosphorylation of eIF2α and altering expression of transcription of genes related to autophagy, endoplasmic reticulum stress, and apoptosis. Bonafide ICD induction by CA5 was confirmed by a C57BL/6 mice vaccination assay with CA5-treated cells. These findings support a high potential of CA5 as an anticancer candidate against AMM.

Oncocalyxone A (onco A) isolated from heartwood of Cordia oncocalyx (Auxemma oncocalyx), exhibits antitumor, analgesic and anti-inflammatory activities. In order to produce drug delivery systems containing onco A, the objective of this study was to develop and validate an HPLC method for quantifying onco A in different media and nanocapsules. The validation method was performed according to ICH guidelines for pharmaceutical products. The solubility of onco A was determined in deionized water, simulated gastric and intestinal fluids, buffer solutions at pH 5.5, 7.0, 9.0 and oils: copaiba, soybean and medium-chain triglycerides. The partition coefficients of onco A between n-octanol, oils and aqueous phase were determined at 25 °C. Accuracy, intra- and inter-day precision values presented low random errors (less than or equal to 2.53, 2.21 and 3.12%, respectively). Onco A solubility was greater in water, buffer solutions, and simulated gastric and intestinal fluids (817 ± 54 μg mL−1) than in oils (434 ± 25 μg mL−1). Onco A showed hydrophilic characteristics (log P

The ability of some microorganisms to use clarified cashew apple juice as carbon and energy source for biosurfactant production was assessed under strict controlled conditions. Twelve strains of Bacillus were isolated and evaluated regarding their biosurfactant production capabilities. The biosurfactant obtained with these selected strains showed the capacity of decreasing the surface tension of water from 72.0 to 31.8 mN.m−1 and the interfacial tension of n-hexadecane to 27.2 mN.m−1, with a critical micelle concentration of 12.5 mg.L−1. Not only did the biosurfactant present excellent stability to pH, temperature and salinity, it also showed emulsifying properties in different hydrocarbons. The behavior of the phase diagrams showed the potential of the produced biosurfactant to obtain relatively-stable emulsions for up to 96 h, which allows for its application in several areas. The semi-purified biosurfactant did not show toxicity against Lactuca sativa (lettuce) or Artemia salina (microcrustacean), presenting an LC50 of 612.27 μ mL-1. The surfactant was characterized as being a cyclic lipopeptide with molecular structure similar to that of surfactin. Furthermore, through the employment of the surfactant produced, the remediation effect in oil-contaminated soil could be significantly improved.

The phytochemical reinvestigation from the heartwood of the extracts of Cordia glazioviana led to the isolation of four still undescribed hydroquinones derivatives designated as cordiaquinol D (1), cordiaquinol E (2), (10R)-10,11-dihydrofuran-1,4-dihydroxy-globiferin (3) and 2-[(1’E,6’E)-3’,8’‑dihydroxy-3’,7’-dimethylocta-1’,6’-dienyl]-benzene-1,4-diol (4), along with the naphthoquinone 6-[(2’R)-2’-hydroxy-3’,6’-dihydro-2H-pyran-5’-yl]-2‑methoxy- 7‑methylnaphthalene-1,4-dione (5). Additionally, six previously known compounds were also isolated: rel-1,4-dihydroxy-8α,11α;9α,11α-diepoxy-2-methoxy-8aβ-methyl- 5,6,7,8,8a,9,10,10a‑octahydro-10-antracenone (6), didehydroconicol (7), 1β,6β-dihydroxy-7-epieudesm-3-ene (8), 1β,6β-dihydroxy-7-epi-eudesm-4(15)-ene (9), 10,11-dihydroxybisabolol (10), and hamanasal-A (11). The structures of the new compounds were assigned by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) analyses. The relative stereochemistry of 3, 4, and 5 was improved by quantum mechanical calculations. Eight, out of the eleven isolated compounds (2-9), were tested through cellular viability and lipopolysaccharide (LPS)-induced inflammation assays against RAW 264.7 macrophage-like cells. Compounds 3-5 exhibited a stronger effect on LPS-induced NO production (half-maximal inhibitory concentration (IC50) 50.34, 105.83, and 66.73 μM, respectively).

Magnetic nanocomposites were synthesized for the targeted delivery of hydrophilic bioactives through guidance generated by a magnetic field. Superparamagnetic iron oxide nanoparticles (SPIONs) were used to generate hydroxyethyl starch magnetic nanocapsules (HES MNCs). This synthesis allowed the co-encapsulation of oncocalyxone A (onco A) and surface-modified magnetite nanoparticles (Fe3O4@citrate) into the same nanostructure. The synthesized nanocapsules exhibited a core-shell morphology, with an average diameter of 143 nm. This nanocomposite showed potential anticancer activity (IC50) against four human tumor cell lines: glioblastoma SNB-19 (1.010 μgmL−1), colon carcinoma HCT-116 (2.675 μgmL−1), prostate PC3 (4.868 μgmL−1), and leukemia HL-60 (2.166 μgmL−1). Additionally, in vivo toxicity and locomotor activity were evaluated in a zebrafish (Danio rerio) model. The nanocomposite exhibited in vitro cytotoxicity, prolonged drug release profile and also responded to an applied magnetic field, representing a versatile compound with perspectives for highest concentration of different hydrophilic bioactives in a target tissue through magnetic vectorization.

Oncocalyxone A, a 1,4-benzoquinone derived from Cordia oncocalyx, exhibits anti-inflammatory, antimicrobial and antidiabetic properties. The aim of this study was to (1) examine the cytotoxic actio...

Leishmaniasis is caused by several protozoan species of Leishmania, and being endemically present in 98 countries around the world, it is also a severe public-health problem. The available antileishmanial drugs are toxic and yet present risks of recurrent infection. Efforts to find new, effective, and safe oral agents for the treatment of leishmaniasis are continuing throughout the world. This work aimed to evaluate the antileishmania activity of cordiaquinone E (CORe), isolated from the roots of Cordia polycephala (Lam.) I. M. Johnston. Cytotoxicity, and possible mechanisms of action against promastigote and amastigote forms of Leishmania amazonensis were examined. CORe was effective in inhibiting promastigote (IC50 4.5 ± 0.3 µM) and axenic amastigote (IC50 2.89 ± 0.11 µM) growth in concentrations found non-toxic for the host cell (CC50 246.81 ± 14.5 µM). Our results revealed that CORe presents direct activity against the parasite, inducing cell death by apoptosis. CORe present greater activity against intracellular amastigotes (EC50 1.92 ± 0.2 µM), yet with much higher selectivity indexes than the reference drugs, being respectively more benign towards RAW 264.7 macrophages than meglumine antimoniate and amphotericin B, (respectively by 4.68 and 42.84 fold). The antiamastigote activity was associated with increased TNF-α, IL-12, NO, and ROS levels, as well as decreased IL-10 levels. These results encourage the progression of studies on this compound for the development of new leishmanicidal agents.

Melanoma is a type of skin cancer with an elevated incidence of metastasis and chemoresistance. Such features hamper treatment success of these neoplasms, demanding the search for new therapeutic options. Using a two-step resin-based approach, we recently demonstrated that cytotoxic prodiginines bind to the inhibitor of apoptosis protein, survivin. Herein, we explore the role of survivin in melanoma and whether its modulation is related to the antimelanoma properties of three cytotoxic prodiginines (prodigiosin, cyclononylprodigiosin, and nonylprodigiosin) isolated from marine bacteria. In melanoma patients and cell lines, survivin is overexpressed, and higher levels negatively impact survival. All three prodiginines caused a decrease in cell growth with reduced cytotoxicity after 24 h compared to 72 h treatment, suggesting that low concentrations promote cytostatic effects in SK-Mel-19 (BRAF mutant) and SK-Mel-28 (BRAF mutant), but not in SK-Mel-147 (NRAS mutant). An increase in G1 population was observed after 24 h treatment with prodigiosin and cyclononylprodigiosin in SK-Mel-19. Further studies indicate that prodigiosin induced apoptosis and DNA damage, as detected by increased caspase-3 cleavage and histone H2AX phosphorylation, further arguing for the downregulation of survivin. Computer simulations suggest that prodigiosin and cyclononylprodigiosin bind to the BIR domain of survivin. Moreover, knockdown of survivin increased long-term toxicity of prodigiosin, as observed by reduced clonogenic capacity, but did not alter short-term cytotoxicity. In summary, prodiginine treatment provoked cytostatic rather than cytotoxic effects, cell cycle arrest at G0/G1 phase, induction of apoptosis and DNA damage, downregulation of survivin, and decreased clonogenic capacity in survivin knockdown cells.

The physicochemical stability and bioavailability of oncocalyxone A (onco A), a quinone isolated from Auxemma oncocalyx tree, could be improved by supramolecular inclusion complexes with cyclodextrins (CDs). The aim of this study was thus to elucidate the complexation of onco A with different CDs using isothermal titration calorimetry (ITC) and molecular modeling. Data from the most favorable host:guest interaction made it possible to obtain onco A:HP-γ-CD inclusion complex, which was characterized by FTIR, 1HNMR, DSC and TG. Experimental results showed that onco A tends to interact more favorably with HP-γ-CD (K = 3175 M−1) with the most favorable Gibbs free energy (ΔG = −19.98 kJ.mol−1). Thermodynamic analysis indicates that the formation of the inclusion complex was entropy-driven (-TΔS = −19.54 kJ.mol−1), associated mainly with the hydrophobic interactions and release of water molecules from the cavity of the CD. Taken together, physicochemical analysis showed host:guest intermolecular interactions between onco A and the cavity of the HP-γ-CD, thereby confirming the formation of the inclusion complex. Moreover, molecular docking results showed two main orientations in which the interaction of the hydroxyl group and a hydroxymethyl group at the wider rim of the HP-γ-CD was more stable (average docking energy of −7.3 kcal/mol) than the one involving the methoxy group with two carbonyl groups at the wider rim (−7.1 kcal/mol). In conclusion, onco A:HP-γ-CD inclusion complex based on results of rational approaches was obtained for use in for further pharmaceutical application in drug delivery systems in cancer therapy.

Withanolides constitute a valuable class of bioactive natural products because some members of the class are known to exhibit cytotoxic activity and also induce a cytoprotective heat-shock response. In order to understand the relationship between their structures and these dual bioactivities of the withanolide scaffold, we obtained 25 analogues of withaferin A (WA) and withanolide D (WD) including 17 new compounds by semisynthesis involving chemical and microbial transformations. Hitherto unknown 16β-hydroxy analogues of WA and WD were prepared by their reaction with triphenylphosphine/iodine, providing unexpected 5β-hydroxy-6α-iodo analogues (iodohydrins) followed by microbial biotransformation with Cunninghamella echinulata and base-catalyzed cyclization of the resulting 16β-hydroxy iodohydrins. Evaluation of these 25 withanolide analogues for their cytotoxicity and heat-shock-inducing activity (HSA) confirmed the known structure-activity relationships for WA-type withanolides and revealed that WD analogues were less active in both assays compared to their corresponding WA analogues. The 5β,6β-epoxide moiety of withanolides contributed to their cytotoxicity but not HSA. Introduction of a 16β-OAc group to 4,27-di- O-acetyl-WA enhanced cytotoxicity and decreased HSA, whereas introduction of the same group to 4- O-acetyl-WD decreased both activities.

In the present study, we integrated liquid chromatography high-resolution mass spectrometry (LC-HRMS) and high-throughput DNA sequencing for prospecting cytotoxic specialized metabolites from Pseudofusicoccum stromaticum, an endophytic fungus associated to the medicinal plant Myracrodruon urundeuva. LC-HRMS profiling allowed identifying putatively eleven compounds in the ethyl acetate extract from P. stromaticum broth. Additionally, a chemical fractionation guided by cytotoxicity combined with spectrometric analysis resulted in the isolation of three compounds: the cyclopeptide cyclo-L-Phe-D-Leu-L-Leu-L-Leu-L-lle along with the known rotenoids rotenolone and tephrosin. MTT assay showed that tephrosin (IC50 0.51 μg mL−1) has strong cytotoxic effect and may be pointed out as the compound responsible for the antiproliferative activity of P. stromaticum. Next Generation Sequencing (NGS) and genome mining of P. stromaticum draft genome revealed 56 contigs codifying specialized metabolites biosynthesis-related enzymes. Nearly half of such genes (44.6%) could be mapped to orphan Biosynthetic Gene Clusters (BGCs) of related plant pathogens belonging to family Botryosphaeriaceae. Also, screening for rotenoids biosynthetic enzymes led to characterization of a putative chalcone isomerase-like (CHI-like) protein. This is the first report of rotenoids biosynthesized by a fungus, unveiling a unique ability of P. stromaticum.

Background Oncocalyxone A (oncoA) is a natural benzoquinone isolated from Cordia oncocalyx, which exhibits many biological activities such as anti-tumor, anti-inflammatory, antioxidant, and hypoglycemic. However, it presents renal, cardiac, and pulmonary toxicity, which can be a limiting factor. The encapsulation of oncoA in polymeric nanoparticles can enhance its therapeutic effect, while reducing its toxicity. Objective Thus, this study aimed to develop nanoparticles of poly (isobutyl cyanoacrylate) containing oncoA, and to evaluate its activity against metastatic breast cancer cells. Methods The nanoparticles were obtained using the anionic emulsion polymerization technique and characterized by Fourier-transform Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), Differential Scanning Calorimetry (DSC), and Thermogravimetry (TG), in addition to studies of long-term stability, including different pH, and blood compatibility. Antiproliferative activity was assessed by MTT and cell migration assays. Results The nanoparticles were obtained with a particle size of 305 ± 6.49 nm and encapsulation rate of 101.5 ± 1.4%, and were stable at different pH over 7 months. The nanoparticles did not induce hemolysis. The encapsulation of oncoA in fucoidan-coated PIBCA nanoparticles increased its cytotoxicity on MDA-MB-231 cells, and inhibited cell migration. Conclusion In conclusion, fucoidan-coated PIBCA nanoparticles containing oncoA may be a promising alternative for further anticancer in vivo studies.

Previous studies demonstrated that the crude extract of the ascidian Eudistoma vannamei, endemic from northeasttern Brazil, strongly hinders growth of tumor cells in vitro by inducing apoptosis due to tryptophan derivatives, which are commonly found in bacteria. This study presents a bioactivity-guided screening among actinomycetes, associated with E. vannamei, aiming at recognizing active principles with biological relevance. Twenty strains of actinomycetes, designated as EVA 0101 through 0120, were isolated from colonies of E. vannamei among which 11 were selected for cytotoxicity evaluation. The extracts from EVA 0102, 0103, 0106, 0109 and 0113 were the most active, and were further studied for IC50 determination and chemical analysis by 1H NMR. IC50 values obtained ranged from 3.62 μg mL-1 (for EVA 0109 in leukemia cells) to 84.65 μg/mL (for EVA 0106 in melanoma cells). All active extracts exhibited the same TLC and spectroscopic profiles, suggesting the presence of quinones and other related secondary metabolites. Furthermore, these strains were identified and compared based on their respective 16S rRNA sequences. The results herein identified the five strains as Micromonospora spp. while phylogenetic analysis suggests that they are possibly two different Micromonospora species producing the cytotoxic compounds. Estudios previos demostraron que el extracto crudo de la ascidia Eudistoma vannamei, endémica de la costa noreste de Brasil, obstaculiza fuertemente el crecimiento de células tumorales in vitro por inducir apoptosis. El análisis químico del extracto sugirió la presencia de derivados de triptófano, comúnmente encontrados en bacterias. El estudio presenta un screening de citotoxicidad en actinomicetos asociados con E. vannamei, para reconocer principios activos biológicamente relevantes. Veinte cepas de actinomicetos, designados como EVA 0101 hasta 0120, fueron aisladas de colonias de E. vannamei y 11 fueron seleccionadas para la evaluación de citotoxicidad. Los extractos de EVA 0102, 0103, 0106, 0109 y 0113 resultaron las más activas y fueron estudiadas para determinación de la CL50 y perfiles de CCF y 1H RMN. Las CL50 obtenidas oscilaron entre 3,62 (EVA 0109 en las células de leucemia) y 84,65 μg mL-1 (EVA 0106 en las células de melanoma). Los extractos activos presentan el mismo perfil de CCF y espectroscópico, lo que sugiere la presencia de quinonas y metabolitos secundarios relacionados. Además, las cinco cepas fueron identificadas y comparadas sobre la base de sus secuencias de 16S ARNr. Las que se identificaron como Micromonospora spp. y el análisis filogenético sugiere que sean por lo menos dos especies de Micromonospora las que producen los compuestos citotóxicos. 335

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.

Our study aimed at the development of a method based on ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-ESI-MS) using selected ion monitoring for the simultaneous quantitation of the alkaloids galantamine, pseudolycorine, sanguinine and narciclasine in Amaryllidaceae species (Hippeastrum elegans, Habranthus cf. irwinianus, Hymenocallis littoralis and Griffinia nocturna). The alkaloids were extracted from dried and ground bulbs (100 mg) using liquid-liquid microextraction followed by solid phase extraction in cation exchange cartridges. The quantification method showed good linearity (correlation coefficient, R ≥ 0.9968) and selectivity for a run time of 10 min. All values were within the acceptable limits for recovery (87.5-96.2%), interday (coefficient of variation, CV%, 1.3-8.4%) and intraday precision (CV% 5.7-8.1%), except narciclasine (70%). The limits of detection and quantification were 5-100 and 20-350 ng mL-1, respectively. Our method demonstrated to be rapid, sensitive and reliable, therefore appropriate for being employed in the prospection of new source of galantamine and other alkaloids.

Six previously undescribed tropane alkaloids, designated as erythrobezerrines A-F, were isolated from the EtOH extract from the stem bark of Erythroxylum bezerrae Plowman. Their structures were elucidated based on the interpretation of the NMR and MS data and in some instances, confirmed by X-ray diffraction analysis. The cytotoxicity of the isolated compounds was evaluated against the cancer cell lines L929, PC-3, HCT-116, SNB-19 and NCI-H460, but only erythrobezerrine C showed moderate activity with IC50 values of 3.38 and 5.43 μM for HCT-116 and NCI-H460, respectively.

The new glucosyl sarpagan alkaloid designated as 21(R*)-(O-β-glucosyl)-hydroxy-sarpagan-17-oic acid, along with eleven known alkaloids were isolated from a soluble alkaloidal fraction from the ethanol extract of Rauvolfia ligustrina. Their structures were elucidated by interpretation of spectroscopic data (1D and 2D NMR), HRESIMS experiment, GIAO 13C NMR calculations, and comparison with literature data. All the isolated alkaloids were screened by their neuroinhibitory effects using the electrically stimulated mice vas deferens bioassay. Compounds 1, 2 and 9 presented a potent inhibitory effect in the neurotransmission while 3 and 11 showed an acute neuroexcitatory effect. Compound 10 exhibited a very effective post-synaptic inhibitory activity.

Ethnopharmacological relevance Himatanthus drasticus is an important medicinal plant whose latex is traditionally used in Northeast Brazil to treat various diseases, including diabetes. The use of α-amylase and α-glucosidase inhibitors can be an effective strategy to modulate levels of postprandial hyperglycemia via control of starch metabolism. Aims of the study This study aimed to verify if H. drasticus latex has inhibitory activity against enzymes linked to type 2 diabetes, besides chemically characterizing the metabolites responsible for such activities. In addition, in silico analysis was performed to support the traditional claim of possible antidiabetic activity of this latex. Materials and methods Latex from H. drasticus stems was sequentially partitioned with n-hexane (FHDH), CHCl3 (FHDC) and EtOH (FHDHA). Wash extraction of the FHDHA fraction was performed to obtain the other extract fractions. The FHDHA was submitted to chromatography in a SPE C18 cartridge using gradient elution with MeOH/H2O to produce five fractions: FHDHA1, FHDHA2, FHDHA3, FHDHA4 and FHDHA5. The FHDHA1 was subjected to semi-preparative reverse phase HPLC. Lineweaver-Burk plots were used to investigate the kinetic parameters of α-amylase and α-glucosidase inhibitory activity. The interactions between plumieride and porcine pancreatic α-amylase and α-glucosidase were analyzed through an in silico molecular docking study. Results Phytochemical identification of compounds present in the FHDHA fraction of H. drasticus latex was possible by 1H, 13C NMR analysis and mass spectrometry, and the results were compared with the literature. The identified compounds were α-ethyl glucoside, protocatechuic acid, 3-O-caffeoylquinic acid, 15-demethylplumieride acid, 5-O-caffeoylquinic acid, caffeic acid, vanillic acid, plumieride, and catechin. The inhibition results of the fractions tested against α-amylase and α-glucosidase showed inhibitory activities dependent on the increase of fractions and compound concentrations. The IC50 results obtained from FHDHA, FHDHA1 and plumieride fractions against α-amylase were 36.46, 72.61, 33.87 μg/mL respectively. The IC50 of plumieride was the closest to that of acarbose (22.52 μg/mL), a result similar to that obtained for α-glucosidase. The type of inhibition was competitive for both enzymes. Conclusions There was strong inhibition of α-amylase and α-glucosidase by FHDHA, FHDHA1 and plumieride, suggesting that these enzymes slow glucose absorption.

Three new 3-hydroxy-N-methyl-2-oxindole (1 and 2) and 4-hydroxy-pyran-2-one (3) derivatives, along with the known 3-hydroxy-N-methyl-2-oxindole (4) and 6-methoxy-N-methylisatin (5) were isolated from a marine Salinispora arenicola strain from sediments of the St. Peter and St. Paul Archipelago, Brazil. The structures of the new compounds were elucidated by a combination of spectroscopic (1D and 2D NMR and HR-ESIMS) data, including single-crystal X-ray diffraction analysis for 2 and 3. Compounds 1 to 5 were assayed for their antimicrobial properties, but only 4 and 5 were active against Enterococcus faecalis with MIC value of 15.6 μg/mL.

The present study evaluated the effect of the addition of antioxidants anethole (AN) and robinin (RO) in the vitrification solution, and the in vitro incubation (IVI) medium of ovine ovarian tissue. Ovarian fragments were vitrified without antioxidant (VWA) or with different concentrations of AN (30, 300 and 2000 μg/mL) or RO (0.125, 0.25 and 0.50 mg/mL), followed by IVI (24 h). Histological analyses showed that the percentage of morphologically normal preantral follicles (MNPF) in AN 2000 did not differ from RO 0.125 or fresh ovarian tissue (CTR). Subsequently, ovarian fragments were vitrified in the presence of AN 2000 and RO 0.125 followed by IVI without or with (AN 2000+ and RO 0.125+) the same antioxidants. The follicular activation in all treatments was significantly increased as compared to the CTR. The stroma cell density (SCD) in all the vitrified fragments was significantly lower than the CTR. However, in the AN 2000 and RO 0.125 this parameter was significantly higher when compared to the VWA. The reactive oxygen species (ROS) in the ovarian cortex of the AN 2000 or AN 2000+ were significantly reduced in comparison with the CTR while the intracellular ROS levels of AN 2000 and CTR were similar. The total antioxidant capacity (TAC) in RO 0.125 was significantly higher than that of VWA, AN 2000 and AN 2000+. According to the results, the use of antioxidants (AN or RO) only in the vitrification solution of ovine ovarian tissue is recommended, due to their better preservation of the SCD. Moreover, AN 2000 best maintains the follicular morphology, while RO 0.125 has a high TAC.

The objective of this study was to determine whether preantral follicles cultured in vitro for 7 days within ovine ovarian cortical strips could be isolated at the secondary follicles (SF) and grown until antral stage during an additional 6 days period of in vitro culture in the presence of aqueous extract of Justicia insularis. Fresh ovarian fragments from 16 adult sheep were fixed for histological analysis (Control 1) or in vitro cultured individually in α-MEM+ supplemented with 0.3 mg/ml J. insularis (Step 1) for 7 days. Part of the fragments then were fixed for histological analysis (in vitro culture group). Remaining fragments were exposed stepwise to increasing trehalose concentrations before immediate isolation of SF and viability assessment (Control 2) or after 6 days of culture in α-MEM++ supplemented with 0.3 mg/ml J. insularis (Step 2). In Step 1, percentage of follicular activation was 80%. In Step 2, a significant increase (p

Benzodiazepines are commonly used to treat disorders of the central nervous system, including anxiety. However, due to their adverse effects, there is a continuing interest in discovering new safe and effective drugs. Marine natural products have emerged as a prolific source of bioactive nitrogenated compounds. Aiming to discover new biologically active natural compounds, the marine sponge Aplysina fulva, a nitrogen-bearing heterocyst producer, was investigated. The main isolated compounds (4, 6, and 9) were evaluated on adult zebrafish (Danio rerio). A group of fishes (n = 6) was preliminarily subjected to acute toxicity, and open field tests using 0.1, 0.5, and 1.0 mg/mL (v. o.) of those compounds was performed. The anxiolytic effect was further investigated in the light/dark assay based on the locomotor response at zebrafish. Interactions through the GABAergic system were investigated using flumazenil, a silent modulator of GABA receptors. To improve the results, a study of molecular docking using the GABAA receptor also was performed. Based on the results, the bromotyrosine derivative compounds 4, 6, and 9 exhibited anxiolytic-like effects mediated by the GABAergic system.

Quinones are a classic example of molecules isolated from natural products. These compounds are secondary metabolites produced by plants, fungi, bacteria, and insects and correspond to an interesting chemical class ubiquitously found in nature. The [rel-8α-Hydroxy-5-hydroxymethyl-2-methoxy-8α, β-methyl-7, 8, 8a, 9-tetahydro-1, 4-anthracenedione] [oncocalyxone A, onco-A] is a benzoquinone of dark red color isolated from the ethanolic extract of the species Cordia oncocalyx (Auxemma oncocalyx Allem). In this review, we aimed to investigate the main biological activities described for oncocalyxone A, as well as its isolation and characterization processes. For this review, the following descriptors were employed in multiple databases: medicinal plants, quinones, Auxemma oncocalyx, Cordia oncocalyx, biological activity. Besides, experimental papers published in international journals and with full text available were used as inclusion criteria. The biological activity profiles found for onco-A according to the literature were: antiproliferative/cytotoxic effects against SW1573 (alveolar cell carcinoma) and CCD922 (normal skin fibroblasts) cell lines; anti-inflammatory and analgesic potential; inhibitory effect on cell growth and DNA reactivity; antiplatelet activity; antitumor potential; anti-glycation agent; beneficial and/or toxic potential in goats and neuroinhibitory effect; antibacterial and antibiofilm activity. The substance has a broad spectrum of pharmacological applications, most of which are associated with its cytotoxic activity. The work also intends to compile the activities described in the literature, to understand how the molecule acts on the various targets, but, in some cases, more in-depth research is needed to elucidate the mechanisms of action. Las quinonas son un ejemplo clásico de moléculas aisladas de productos naturales. Estos son metabolitos secundarios de plantas, hongos, bacterias e insectos, y corresponden a una clase química interesante que se encuentra ubicuamente en la naturaleza. La [rel-8α-hidroxi-5-hidroximetil-2-metoxi-8α, β-metil-7, 8, 8a, 9-tetahidro-1, 4-antracenodiona] [oncocalyxona A, onco-A] una benzoquinona de color oscuro color rojo aislado del extracto etanólico de la especie Cordia oncocalyx (Auxemma oncocalyx Allem). En esta revisión, proponemos investigar las principales actividades biológicas descritas para la oncocalyxona A, desde su aislamiento hasta el proceso de caracterización. Métodos. Para esta revisión, se emplearon los siguientes descriptores en múltiples bases de datos: plantas medicinales, quinonas, Auxemma oncocalyx, Cordia oncocalyx, actividad biológica. Además, se utilizaron como criterios de inclusión artículos experimentales publicados en revistas internacionales y con texto completo disponible. Resultados y discusión. Los perfiles de actividad biológica encontrados para onco-A según la literatura fueron: antiproliferativo/citotóxico en leucemia, tumor de pulmón [SW1573] y fibroblastos de piel normal [CCD922]; antiinflamatorio y analgésico; efecto inhibidor sobre el crecimiento celular y la reactividad del ADN; actividad antiplaquetaria; potencial antitumoral; agente anti-glicación; potencial beneficioso y / o tóxico en cabras y efecto neuroinhibidor; actividad antibacteriana y antibiofilm. La sustancia tiene un amplio espectro de aplicaciones farmacológicas, la mayoría de las cuales están interconectadas con la actividad citotóxica. El trabajo busca, además de recopilar las actividades descritas en la literatura, comprender cómo actúa la molécula sobre las distintas dianas, pero, en algunos casos, se necesita una investigación más profunda para dilucidar los mecanismos de acción de la misma. As quinonas são um exemplo clássico de moléculas isoladas de produtos naturais. Estes são metabólitos secundários de plantas, fungos, bactérias e insetos, e correspondem a uma classe química interessante encontrada ubiquamente na natureza. O [rel-8α-hidroxi-5-hidroximetil-2-metoxi-8α, β-metil-7, 8, 8a, 9-tetahidro-1, 4-antracenediona] [oncocalixona A, onco-A] uma benzoquinona escura cor vermelha isolada do extrato etanólico da espécie Cordia oncocalyx (Auxemma oncocalyx Allem). Nesta revisão, propomos investigar as principais atividades biológicas descritas para a oncocalixona A, desde o seu isolamento até o processo de caracterização. Para esta revisão, os seguintes descritores foram empregados em múltiplas bases de dados: medicinal plants, quinones, Auxemma oncocalyx, Cordia oncocalyx, atividade biológica. Além disso, artigos experimentais publicados em periódicos internacionais e com texto completo disponível foram utilizados como critérios de inclusão. Os perfis de atividade biológica encontrados para o onco-A de acordo com a literatura foram: efeito antiproliferativo/citotóxico nas linhagens celulares SW1573 (carcinoma de células alveolares) e CCD922 (fibroblastos normais de pele); antiinflamatório e analgésico; efeito inibitório sobre o crescimento celular e reatividade do DNA; atividade antiplaquetária; potencial antitumoral; agente anti-glicação; potencial benéfico e / ou tóxico em caprinos e efeito neuroinibitório; atividade antibacteriana e antibiofilme. A substância possui um amplo espectro de aplicações farmacológicas, muitas das quais interligadas à atividade citotóxica. O trabalho busca, além de compilar as atividades descritas na literatura, entender como a molécula atua nos diversos alvos, mas, em alguns casos, pesquisas mais aprofundadas são necessárias para elucidar seus mecanismos de ação.

Seven withanolides, including four previously unknown, were isolated from the acetone and ethanol extracts of cultivated specimens of Acnistus arborescens . These four compounds were identified as rel -(18 R ,22 R )-5 β ,6 β :18 β ,20-diepoxy-3 β ,18 α -dimethoxy-4 β -hydroxy-1-oxowith-24-enolide, rel -(20 R ,22 R )-5 β ,6 β -epoxy-4 β ,16 α ,20-trihydroxy-1-oxowitha-2,24dienolide, rel -(20 R ,22 R )-16 α -acetoxy-6 α -chloro-4 β ,5 β ,20-trihydroxy-1-oxowitha-2,24-dienolide and rel -(20 R ,22 R )-16 α -acetoxy-20-hydroxy-1-oxowitha-2,5,24-trienolide. Their structures were elucidated by interpretation of spectroscopic data (1D and 2D NMR), HRESIMS experiments and comparison with published data for similar compounds. Cytotoxicity of the isolated compounds was evaluated against a panel of four tumor cell lines (HL-60, HCT-116, SF-268 and PANC-1). Withanolide D was the most active, with an IC 50 value in the range of 0.3–1.7 μM, rel -(18 R ,22 R )-5 β ,6 β :18 β ,20-diepoxy-3 β ,18 α -dimethoxy-4 β -hydroxy-1-oxowith-24-enolide and rel -(20 R ,22 R )-5 β ,6 β -epoxy-4 β ,16 α ,20-trihydroxy-1-oxowitha-2,24dienolide were moderately active, while all the others were non-cytotoxic.

Resistance to antimicrobials is a challenging issue that complicates the treatment of infections caused by bacteria and fungi, thus requiring new therapeutic options. Oncocalyxone A, a benzoquinone obtained from Auxemma oncocalyx (Allem) Taub has several biological effects; however, there is no data on its antimicrobial action. In this study, its antimicrobial and antibiofilm activities were evaluated against bacteria and fungi of clinical interest. Strains of Gram-positive and Gram-negative bacteria, and filamentous fungi and yeasts were selected to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of oncocalyxone A. The antibacterial effect of oncocalyxone A was studied using survival curves, atomic force microscopy (AFM), and the involvement of oxidative stress. We examined the inhibitory action of the molecule on biofilm formation and its hemolytic activity against human erythrocytes. Our results showed that among the strains tested, Staphylococcus epidermidis was highly sensitive to the action of oncocalyxone A, with an MIC of 9.43 μg/mL. In most bacterial strains analyzed, a bacteriostatic effect was observed, though the molecule showed no antifungal activity. Antibiofilm activity was observed against the methicillin-resistant S. aureus bacteria. Additionally, results from atomic force microscopy imaging showed that oncocalyxone A significantly altered bacterial morphology. Further, oncocalyxone A showed no hemolytic activity at concentrations ≥151 μg/mL. Together, our results demonstrate the antibacterial and antibiofilm potential of oncocalyxone A, indicating its therapeutic potential against bacterial resistance.

Amphidinolides are cytotoxic macrolides produced by symbiotic unicellular microalgae of the genus Amphidinium. Here we describe the identification of four related molecules belonging to this macrolide family isolated from the invertebrate Stragulum bicolor. The new molecules, named amphidinolide PX1-PX3 and stragulin A (1&ndash, 4), show an unprecedented carbon skeleton whose complete stereochemistry has been determined by spectroscopic and computational methods. Differences in the structures of these molecules modulate their biological activity in a panel of tumor cell lines, but the opened derivative stragulin (4) shows a very potent and specific cytotoxic activity (IC50 0.18 &micro, M) against the aggressive human melanoma cell A2058.

Salinaphthoquinones A-E (1-5) were isolated from a marine Salininispora arenicola strain, recovered from sediments of the St. Peter and St. Paul Archipelago, Brazil. The structures of the compounds were elucidated using a combination of spectroscopic (NMR, IR, HRESIMS) data, including single-crystal X-ray diffraction analysis. A plausible biosynthetic pathway for 1-5 is proposed. Compounds 1 to 4 displayed moderate activity against Staphylococcus aureus and Enterococcus faecalis with MIC values of 125 to 16 μg/mL.

The present study evaluated the effect of supplementing in vitro culture medium with J. insularis compared to FSH on isolated secondary follicles and in vitro maturation of oocytes from those follicles. Secondary follicles were isolated from sheep ovaries and individually cultured for 18 days in α-MEM+ (Control), α-MEM+ supplemented with 100 ng/mL recombinant bovine follicle stimulating hormone (FSH) or with 0.3, 1.25, or 2.5 mg/mL of J. insularis extract (JI0.3, JI1.25, and JI2.5, respectively). Culture medium collected every 2 days was used to measure ROS levels. At the end of the culture period, cumulus oocytes complex (COCs) were collected and matured in vitro. Follicular walls were used for mRNA quantitation. JI0.3 led to a higher (P < 0.05) percentages of intact follicles than other groups after 18 days of culture. While follicular diameter remained unchanged from Day 6 onwards with JI0.3 and FSH, percentages of antral cavity formation were higher (P < 0.05) with JI0.3 at Day 6 than in all other treatments. No differences were observed between controls and treatment groups regarding ROS levels and mRNA expression of genes. Viability of resulting oocytes was higher (P < 0.05) in JI0.3 compared to FSH. Interestingly, in control experiment, supplementation of maturation medium with JI0.3 led to higher (P < 0.05) percentages of metaphase II compared to controls. Although more validations will be needed, it seems that this natural extract could be used as a cheap and easily available alternative to commercial FSH.

Background:Auxemma oncocalyx and its main component oncocalyxone A (onco A) have a high level of antioxidant and antitumor activity, but there are no studies on the action of both of these drugs regarding folliculogenesis. Material and Methods: Caprine ovarian tissue fragments were fixed (non-cultured control) or cultured for 1 or 7 days in α-MEM+ alone (cultured control) or supplemented with dimethyl sulfoxide (DMSO; 20% v/v), bone morphogenetic protein 15 (BMP-15; 100 ng/ml), doxorubicin (DXR; 0.3 g/ml), or different concentrations of A. oncocalyx (1.2, 12, or 34 g/ml) or onco A (1, 10, or 30 g/ml). We analyzed for follicular morphology and growth, apoptosis (terminal deoxynucleotidyl transferase dUTP-biotin nick end labeling (TUNEL) assay), and cell proliferation (silver staining of argyrophilic nucleolus organizer regions (AgNOR) and test for proliferating cell nuclear antigen (PCNA)). Results:A. oncocalyx and onco A (in a concentration-dependent manner) and DXR decreased (P < 0.05) the number of morphologically normal follicles, with no effect (P > 0.05) on follicular growth. A. oncocalyx reduced (P < 0.05) the percentage of normal follicles compared to onco A, whereas DXR, A. oncocalyx 1.2 g/ml, and onco A 1 g/ml increased (P < 0.05) the percentage of TUNEL-positive follicles. DXR decreased (P < 0.05) the number of nucleolus organizer regions. Conclusion:A. oncocalyx and onco A affected the in vitro caprine folliculogenesis in a concentration-dependent manner. Onco A (1 g/ml) has a less harmful effect than DXR on goat preantral follicle survival.

Three new plakortides, 7,8-dihydroplakortide E (1), 2, and 10, along with known natural products 3, 4, spongosoritin A (5), 6-8, and plakortide P (9), were isolated from Brazilian specimens of Plakortis angulospiculatus. Compounds 2, 3, 5, and 7-9 displayed cytotoxic activities with IC50 values ranging from 0.2 to 10 μM. Compounds that contained a dihydrofuran ring were generally less active and displayed time dependence in their activity. The activities of compounds 2 and 7-9, carboxylic acids bearing a common six-membered endoperoxide, were higher overall than for compounds 3 and 5. The modes underlying the cytotoxic actions of plakortides 2, 3, 5, 7, and 9 were further investigated using HCT-116 cells. While dihydrofurans 3 and 5 induce a G0/G1 arrest, six-membered peroxides 2, 7, and 9 delivered a G2/M arrest and an accumulation of mitotic figures, indicating a distinctly different antimitotic response. Confocal analysis indicated that microtubules were not altered after treatment with 2, 7, or 9, therein suggesting that the mitotic arrest may be unrelated to cytoskeletal targets. Overall, we find that two related classes of natural products obtained from the same extract offer cytostatic activity, yet they do so through discrete pathways.

Two new polyunsaturated 3,4-epoxy-heneicosane derivatives named as epoxy-lobophorene A and epoxy-lobophorene B were isolated from the brown alga Lobophora variegata, in addition to nine known compounds. The structures of the new compounds were elucidated using a combination of 1D/2D nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HRMS). The isolated compounds were submitted to antiproliferative assays against the human colon cancer cell line HCT-116, human metastatic prostate cancer PC-3M, murine metastatic melanoma B16-F10 and murine fibroblast cell line L929 and also tested as antibacterial. Both 3,4-epoxy lobophorene A and 3,4-epoxy lobophorene B depicted moderate antiproliferative effect against cell lines. None of them showed antibacterial activity.