HPLC/DAD, Antibacterial and Antioxidant Activities of Plectranthus Species (Lamiaceae) Combined with the Chemometric Calculations.

The increase in antibiotic resistance and the emergence of new bacterial infections have intensified the research for natural products from plants with associated therapy. This study aimed to verify the antibacterial and antioxidant activity of crude extracts of the genus Plectranthus species, being the first report on the modulation of aminoglycosides antibiotic activity by Plectranthus amboinicus extracts. The chemical composition was obtained by chemical prospecting and High-Performance Liquid Chromatography with diode arrangement detector (HPLC/DAD). The antibacterial activities of the extracts alone or in association with aminoglycosides were analyzed using the microdilution test. The antioxidant activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. The phytochemical prospection allowed the flavonoids, saponins, tannins and triterpenoids to be identified. Quercetin, rutin, gallic acid, chlorogenic acid, caffeic acid, catechin, kaempferol, glycosylated kaempferol, quercitrin, and isoquercitrin were identified and quantified. The principal component analysis (PCA) observed the influence of flavonoids and phenolic acids from Plectranthus species on studied activities. Phytochemical tests with the extracts indicated, especially, the presence of flavonoids, confirmed by quantitative analysis by HPLC. The results revealed antibacterial activities, and synergistic effects combined with aminoglycosides, as well as antioxidant potential, especially for P. ornatus species, with IC50 of 32.21 µg/mL. Multivariate analyzes show that the inclusion of data from the antioxidant and antibacterial activity suggests that the antioxidant effect of these species presents a significant contribution to the synergistic effect of phytoconstituents, especially based on the flavonoid contents. The results of this study suggest the antibacterial activity of Plectranthus extracts, as well as their potential in modifying the resistance of the analyzed aminoglycosides.

Phytotoxicity reduction of the mercury chloride effect by natural products from Eugenia jambolana Lam.: A new strategy against the toxic metal pollution.

The objective of this work was to evaluate the antioxidant, metal chelating and cytoprotective activity of the Eugenia jambolana Lam. extract, as well as of its flavonoid and tannic fractions, against the action of Mercury Chloride (HgCl2). Flavonoids were quantified and an LC-MS chromatographic analysis was performed to identify secondary metabolites. Fe2+ and Fe3+ chelation tests and antioxidant activity were carried out using the FRAP method. Microbiological tests were performed by microdilution to determine the Minimum Inhibitory Concentration (MIC). From these results the Minimum Bactericidal (MBC) and Minimum Fungicide Concentration (MFC) were evaluated. The allelopathy and cytoprotection assays were performed using eukaryotic and prokaryotic models. The results revealed the presence of phenolic acids and flavonoids in the E. jambolana extract and fractions. The sub-allelopathic concentration (64 µg/mL) was used and the results demonstrated the E. jambolana potential cytoprotective effect against mercury chloride.

Antibiotic-Potentiating Activity of Phanostenine Isolated from Cissampelos sympodialis Eichler.

Cissampelos sympodialis Eichler is well studied and investigated for its antiasthmatic properties, but there are no data in the literature describing antibacterial properties of alkaloids isolated from this botanical species. This work reports the isolation and characterization of phanostenine obtained from roots of C. sympodialis and describes for the first time its antimicrobial and antibiotic modulatory properties. Phanostenine was first isolated from Cissampelos sympodialis and its antibacterial activities were determined. Chemical structures of the alkaloid isolate were determined using spectroscopic and chemical analyses. Phanostenine was also tested for its antibacterial activity against standard strains and clinical isolates of Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentration (MIC) was determined in a microdilution assay and for the evaluation of antibiotic resistance-modifying activity. MIC of the antibiotics was determined in the presence or absence of phanostenine at sub-inhibitory concentrations. The evaluation of antibacterial activity by microdilution assay showed activity for all strains with better values against S. aureus ATCC 12692 and E. coli 27 (787.69 mm). The evaluation of aminoglycoside antibiotic resistance-modifying activity showed reduction in the MIC of the aminoglycosides (amikacin, gentamicin and neomycin) when associated with phanostenine, MIC reduction of antibiotics ranging from 21 % to 80 %. The data demonstrated that phanostenine possesses a relevant ability to modify the antibiotic activity in vitro. We can suggest that phanostenine presents itself as a promising tool as an adjuvant for novel antibiotics formulations against bacterial resistance.

Potentiation of antibiotic activity of aminoglycosides by natural products from Cordia verbenacea DC.

Medicinal plants are often the only therapeutic resource for many communities and ethnic groups. Cordia verbenacea DC., "Erva-baleeira," is one of the species of plants currently used to produce a phytotherapeutic product extracted from its leaves. The present study aimed to establish its chemical profile, antibacterial activity and resistance-modulating potential. The C. verbenacea extracts were prepared from fresh leaves using solvents as methanol and hexane. Ethyl Acetate was used for the preparation of the fraction. Phytochemical screening was carried out using HPLC-DAD for determination and quantification of the secondary metabolites present in the fractions. Antibacterial and resistance-modulation assays were performed to determine minimum inhibitory concentration (MIC) using a microdilution assay. The data were subjected to statistical analysis with two-way ANOVA and Bonferroni posttests. Results of phytochemical prospecting and HPLC analysis of the fractions were in agreement with the literature. The natural products presented moderate antibacterial activity when considering the clinical relevance of a MIC of 256 µg/mL against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, and 512 µg/mL against P. aeruginosa. However, when the fractions were combined with antibiotics we observed a synergic effect, as natural products enhanced the antibacterial effect of aminoglycosides, significantly decreasing the MIC of antibiotics at 12.5%-98.4%. We believe that the data obtained from phytochemical analysis and from antibacterial and resistance modulation assays of C. verbenacea extracts new can open perspectives in the search for new alternatives for the treatment of bacterial infections and stimulate the renewed use of antibiotics with reduced effectiveness due to resistance.

Psidium guajava L. and Psidium brownianum Mart ex DC.: Chemical composition and anti - Candida effect in association with fluconazole.

The therapeutic combinations have been increasingly used against fungal resistance. Natural products have been evaluated in combination with pharmaceutical drugs in the search for new components able to work together in order to neutralize the multiple resistance mechanisms found in yeasts from the genus Candida. The aqueous and hydroethanolic extracts from Psidium brownianum Mart ex DC. and Psidium guajava L. species were evaluated for their potential to change the effect of commercial pharmaceutical drugs against Candida albicans and Candida tropicalis strains. The tests were performed according to the broth microdilution method. Plate readings were carried out by spectrophotometry, and the data generated the cell viability curve and IC50 of the extracts against the yeasts. A chemical analysis of all the extracts was performed for detection and characterization of the secondary metabolites. The total phenols were quantified in gallic acid eq/g of extract (GAE/g) and the phenolic composition of the extracts was determined by HPLC. Fluconazole and all extracts presented high Minimum Inhibitories Concentrations (MICs). However, when associated with the extracts at sub-inhibitory concentrations (MIC/16), fluconazole had its effect potentiated. A synergistic effect was observed in the combination of fluconazole with Psidium brownianum extracts against all Candida strains. However, for Psidium guajava extracts the synergistic effect was produced mainly against the Candida albicans LM77 and Candida tropicalis INCQS 400042 strains. The IC50 values of fluconazole ranged from 19.22 to 68.1 µg/mL when it was used alone, but from 2.2 to 45.4 µg/mL in the presence of the extracts. The qualitative chemical characterization demonstrated the presence of phenols, flavonoids and tannins among the secondary metabolites. The concentration of total phenols ranged from 49.25 to 80.77 GAE/g in the P. brownianum extracts and from 68.06 to 82.18 GAE/g in the P. guajava extracts. Our results indicated that both P. brownianum and P. guajava extracts are effective on potentiating the effect of fluconazole, and therefore, these plants have the potential for development of new effective drugs for treating fungal infections.

Synthesis, antibacterial and cytotoxic activities of new biflorin-based hydrazones and oximes.

Biflorin 1 is a biologically active quinone, isolated from Capraria biflora. Five new biflorin-based nitrogen derivatives were synthesized, of which two were mixtures of (E)- and (Z)- isomers: (Z)-2a, (Z)-2b, (Z)-3a, (Z)- and (E)-3b, (Z)- and (E)-3c. The antibacterial activity was investigated using the microdilution method for determining the minimum inhibitory concentration (MIC) against six bacterial strains. Tests have shown that these derivatives have potential against all bacterial strains. The cytotoxic activity was also evaluated against three strains of cancer cells, but none of the derivatives showed activity.

Chemical composition and evaluation of acute toxicological, antimicrobial and modulatory resistance of the extract of Murraya paniculata.

CONTEXT: Murraya paniculata (Linn) JACK (Rutaceae) is used in traditional medicine in the treatment of diabetes, inflammation, and microbial disorders. OBJECTIVE: This study determined the polyphenol composition and antimicrobial and acute toxicological activity of the hydroethanolic extract of M. paniculata leaves (EEMp). MATERIALS AND METHODS: Chemical composition was evaluated by the Folin-Ciocalteu and AlCl3 assays and by HPLC-DAD. Antibacterial and modulatory activity was determined by the microdilution method. Toxicity was assessed with a single dose of EEMp administered orally at doses of 2000 and 5000 mg/kg body weight/day in male and female Swiss mice. RESULTS: Total phenolic content of the EEMp samples varied from 66.5 to 396.8 mg gallic acid equivalent/g of extract and flavonoid content varied from 0.3 to 31.1 mg quercetin equivalent/g of extract. The principal component identified by HPLC-DAD assay was ellagic acid. The results of oral acute toxicity showed no mortality, changes in hematological parameters, or CNS and ANS toxicities in rats. Biochemical analysis showed a significant increase in glucose and glutamic oxaloacetic transaminase activity and reduction in triglycerides and cholesterol for 5000 and 2000 mg/kg doses, respectively, when compared with the control group. Histopathological evaluation showed no significant microscopic changes. EEMp showed essentially no antimicrobial activity, but when aminoglycosides were combined with EEMp their MIC was reduced. CONCLUSIONS: Significant effects were observed in the acute toxicity assay, but they had no clinical relevance. The results suggest that M. paniculata could be used as a source of natural products with antibacterial resistance-modifying activity, with lower toxicity.

Chemical composition and evaluation of modulatory of the antibiotic activity from extract and essential oil of Myracrodruon urundeuva.

CONTEXT: The combination of antibiotics with natural products has demonstrated promising synergistic effects in several therapeutic studies. OBJECTIVE: The aim of this study was to determine the effect of a combination of an ethanol extract of Myracrodruon urundeuva Fr. All. (Anacardiaceae) (aroeira plant) and its essential oil with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli from clinical isolates. MATERIALS AND METHODS: After identification of the chemical components by GC-MS, the antibacterial activity of the natural products and antibiotics was assessed by determining the minimal inhibitory concentration (MIC) using the microdilution method and concentrations ranging 8-512 µg/mL and 0.0012-2.5 mg/mL, respectively. Assays were performed to test for a possible synergistic action between the plant products and the antimicrobials, using the extract and the oil at a sub-inhibitory concentration (128 µg/mL) and antibiotic at concentrations varying between 8 and 512 µg/mL. RESULTS: The GC-MS analysis identified the main compound as δ-carene (80.41%). The MIC of the natural products was >1024 µg/mL, except against S. aureus ATCC25923. Only the combinations of the natural products with gentamicin, amikacin and clindamycin were effective against S. aureus 358, enhancing the antibiotic activity by reducing the MIC. CONCLUSIONS: The extract from aroeira showed a higher antibacterial activity and the oil was more effective in potentiating the activity of conventional antibiotics.

Modulation of the norfloxacin resistance in Staphylococcus aureus by Cordia verbenaceae DC.

BACKGROUND & OBJECTIVES: Several chemical compounds isolated from natural sources have antibacterial activity and some enhance the antibacterial activity of antibiotics reversing the natural resistance of bacteria to certain antibiotics. In this study, the hexane and methanol extract of Cordia verbenaceae were assessed for antibacterial activity alone and combinated with norfloxacin against the Staphylococcus aureus strain SA1199B. METHODS: The minimum inhibitory concentration (MIC) of extracts was assayed using microdilution assay and the modulatory activity was evaluated using plate diffusion assay. RESULTS: The MIC observed varied between 256 to >1024 µg/ml. However, the antibiotic activity of norfloxacin was enhanced in the presence of subinhibitory concentrations of hexane extract of C. verbenaceae (HECV). INTERPRETATIONS & CONCLUSIONS: Our results indicate that Cordia verbenaceae DC. can be a source of plant derived products with antibiotic modifying activity.

Phenol composition, cytotoxic and anti-kinetoplastidae activities of Lygodium venustum SW. (Lygodiaceae).

The search for new therapeutic agents has been a constant for the treatment of diseases such as leishmaniasis and Chagas disease. Most drugs used have side effects, justifying the need to evaluate the cytotoxicity of the tested products for candidates to new drugs. In this study, the bioactivity of Lygodium venustum, a cosmopolitan fern of Lygodiaceae, was assessed about their leishmanicidal and trypanocidal potential. The better activity was observed using methanol fraction, with inhibition percentage of 63% and 68% for promastigotes and epimastigotes, respectively, at a concentration of 500 µg/mL. The ethyl acetate and methanol fractions demonstrated a higher cytotoxic potential. This was the first report of leishmanicidal, trypanocidal and cytotoxic activities to L. venustum.

Topical antiinflammatory activity of essential oil of Lippia sidoides cham: possible mechanism of action.

This work reports the chemical composition of the essential oil of Lippia sidoides (EOLS) and evaluation of the topical effect of EOLS and thymol against different irritant agents in vivo. The essential oil was obtained by hydrodistillation, and gas chromatography/mass spectrometry analysis identified the main constituents: thymol (84.9%) and p-cymene (5.33%). The antiinflammatory activity was evaluated using the mouse models of acute ear inflammation induced by croton oil, arachidonic acid, phenol or histamine, and chronic inflammation induced by croton oil. The topical application of EOLS or thymol at a dose of 2 mg/ear significantly reduced (p < 0.001) ear edema induced with arachidonic acid by 45.1% and 47.4% and reduced ear edema induced with phenol by 33.2% (p < 0.05) and 54.7% (p < 0.01) in acute ear edema. However, a proinflammatory effect of EOLS and thymol was evidenced when it was applied for more than 1 day. There were no statistical differences in antiedematogenic activity between EOLS and thymol. In conclusion, the results indicate that thymol is the constituent responsible for the topical antiinflammatory activity of EOLS. Thus, these findings could justify the popular use of L. sidoides by alternative medicine, but chronic use has an inflammatory effect.

Semisynthesis, in silico study and in vitro antibacterial evaluation of fucosterol derivatives.

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.

Anti-Trypanosoma cruzi and cytotoxic activities of Eugenia uniflora L.

Chagas disease is caused by Trypanosoma cruzi, being considered a public health problem. An alternative to combat this pathogen is the use of natural products isolated from fruits such as Eugenia uniflora, a plant used by traditional communities as food and medicine due to its antimicrobial and biological activities. Ethanolic extract from E. uniflora was used to evaluate in vitro anti-epimastigote and cytotoxic activity. This is the first record of anti-Trypanosoma activity of E. uniflora, demonstrating that a concentration presenting 50% of activity (EC(50)) was 62.76 µg/mL. Minimum inhibitory concentration (MIC) was ≤ 1024 µg/mL. Our results indicate that E. uniflora could be a source of plant-derived natural products with anti-epimastigote activity with low toxicity.

Evaluation of the Antimicrobial Activity of the Decoction of Tropidurus hispidus (Spix, 1825) and Tropidurus semitaeniatus (Spix, 1825) Used by the Traditional Medicine.

Tropidurus hispidus and Tropidurus semitaeniatus are two lizard species utilized in traditional medicine in Northeast Brazil. Their medicinal use includes diseases related with bacterial infections such as tonsillitis and pharyngitis. They are used in the form of teas (decoctions) for the treatment of illnesses. In this work, we evaluated the antimicrobial activity of the decoctions of T. hispidus (DTH) and T. semitaeniatus (DTS) against bacterial strains, namely, standard and multiresistant Escherichia coli, Staphylococus aureus, and Pseudomonas aureuginosa, alone and in combination with aminoglycoside antibiotics. The decoctions were prepared using the whole body of the dried lizards, and the filtrate was frozen and lyophilized. When tested alone, the samples did not demonstrate any substantial inhibition of bacterial growth. However, in combination with antibiotics as aminoglycosides, decoctions reduced the minimal inhibitory concentration (MIC) of the assayed antibiotics against multiresistant strains of S. aureus and P. aureuginosa. Chemical prospecting tests revealed the presence of alkaloids in DTS. This is the first study evaluating the medicinal efficacy of T. hispidus and T. semitaeniatus and contributes to the list of new sources of medicines from natural products of animal origin.

Trypanocide, cytotoxic, and antifungal activities of Momordica charantia.

CONTEXT: Chagas disease, caused by Trypanosoma cruzi, is a public health problem. Currently, chemotherapy is the only available treatment for this disease, and the drugs used, nifurtimox and benzonidazol, present high toxicity levels. An alternative for replacing these drugs are natural extracts from Momordica charantia L. (Cucurbitaceae) used in traditional medicine because of their antimicrobial and biological activities. OBJECTIVE: In this study, we evaluated the extract of M. charantia for its antiepimastigote, antifungal, and cytotoxic activities. MATERIALS AND METHODS: An ethanol extract of leaves from M. charantia was prepared. To research in vitro antiepimastigote activity, T. cruzi CL-B5 clone was used. Epimastigotes were inoculated at a concentration of 1 × 10(5) cells/mL in 200 µl tryptose-liver infusion. For the cytotoxicity assay, J774 macrophages were used. The antifungal activity was evaluated by microdilution using strains of Candida albicans, Candida tropicalis, and Candida krusei. RESULTS: The effective concentration capable of killing 50% of parasites (IC(50)) was 46.06 µg/mL. The minimum inhibitory concentration (MIC) was ≤ 1024 µg/mL. Metronidazole showed a potentiation of its antifungal effect when combined with an extract of M. charantia. CONCLUSIONS: Our results indicate that M. charantia could be a source of plant-derived natural products with antiepimastigote and antifungal-modifying activity with moderate toxicity.

Antibacterial and modulatory effect of Stryphnodendron rotundifolium.

CONTEXT: Stryphnodendron rotundifolium Mart. (Leguminosae), a tree in Northeast Brazil (Chapada do Araripe), is used in popular medicine to treat different processes such as inflammation and infectious diseases, mainly caused by bacterial pathogens. OBJECTIVE: This study determined the modulatory and antimicrobial activity of the hydroethanol extract of dried stem bark, the most used form of this natural product, as a remedy by the traditional communities, against standard and clinical isolates of Escherichia coli and Staphylococcus aureus. MATERIAL AND METHODS: The antibacterial and modulatory activities of the hydroalcoholic extract from the leaves were obtained by maceration/hydrodistillation method and assayed by microdilution. RESULTS: In the microbiological assays, growth inhibition was demonstrated by this extract against the bacterial strains tested, with minimal inhibitory concentration (MIC) values of 512 µg/mL. However, when a subinhibitory concentration (MIC/8 = 64 µg/mL) was combined with conventional antimicrobial drugs (gentamicin, kanamycin, amikacin and neomycin), the extract showed a potentiating effect, reducing the MIC for all drugs assayed in a range between 312.5 and 2.4 µg/mL. CONCLUSIONS: We indicate that the extract of S. rotundifolium showed potential synergistic antibiotic activity. With the results obtained, these extracts proved to be a promising source of antibacterial and modulatory agents.

In vitro additive effect of Hyptis martiusii in the resistance to aminoglycosides of methicillin-resistant Staphylococcus aureus.

CONTEXT: Bacterial infectious agents represent a risk to populations, where they are responsible for the high morbidity and mortality. In combating these pathogens, our main line of defense is the use of antibiotics. However, the indiscriminate use of these drugs select resistant strains to these same drugs. OBJECTIVE: In this study the ethanol extract of Hyptis martiusii Benth. (EEHM) (Lamiaceae) was tested for its antimicrobial activity against aminoglycoside multi-resistant Staphylococcus aureus (MRSA). MATERIALS AND METHODS: In this study, the ethanol extract of H. martiusii was prepared and tested with chlorpromazine for its antimicrobial activity using the microdilution method. Chlorpromazine and the ethanol extract were used alone and also in combination with aminoglycosides against a MRSA strain resistant to these antibiotics to determine the participation of efflux systems in resistance mechanisms. The FIC index was calculated and evaluated by the checkerboard method. RESULTS: A potentiating effect between this extract and aminoglycosides was demonstrated. Similarly, a potentiating effect of chlorpromazine with kanamycin was detected, indicating the involvement of an efflux system in the resistance to this aminoglycoside. The checkerboard method with combinations of aminoglycosides and EEHM demonstrated additive effect with kanamycin and gentamicin. It is therefore suggested that extracts from H. martiusii could be used as a source of plant-derived natural products with resistance- modifying activity. CONCLUSION: This is the first report about the modifying antibiotic activity of Hyptis martiusii, constituting a new approach against bacterial resistance to antibiotics as aminoglycosides.

Synthesis of Silver Nanoparticles Using Odontosoria chinensis (L.) J. Sm. and Evaluation of their Biological Potentials.

The present study was aimed to synthesize silver nanoparticles (AgNPs) from the aqueous extracts of Odontosoria chinensis (L.) J. Sm. and the synthesized AgNPs were examined for their biopotentials. The Odontosoria chinensis extracts were added to 1 mM AgNO3 solution with different ratios viz., 0.5: 9.5, 1:9, 1.5: 8.5 and 2: 8 ratios for the reduction of Ag ions. After reduction, the AgNPs of Odontosoria chinensis were analyzed spectroscopically for further confirmation. The synthesized AgNPs of Odontosoria chinensis were characterized by pH, ultra violet-visible spectroscopy (UV-Vis), Fourier transform-infra red spectroscopy (FT-IR), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDAX) and X-Ray diffraction (XRD). The time taken for the complete reduction of Silver (Ag) in solution to nanoparticle was 10 min. The O. chinensis aqueous extracts mediated silver nanoparticles showed a broad peak with distinct absorption at around 400-420 nm and confirmed the silver nanoparticle formation. FT-IR results also confirmed the existence of organic materials in the silver nanoparticles of O. chinensis. The EDX spectra of AgNPs of O. chinenesis revealed the occurrence of a strong Ag peak. The synthesis of AgNPs of O. chinenesis was confirmed with the existence of a peak at 46.228°. The toxic potential of AgNPs of O. chinenesis showed varied percentage mortality with the LC50 values of 134.68 µL/ 50 mL and 76.5 µL/50 mL, respectively. The anti-inflammatory and anti-diabetic activities of aqueous and AgNPs of O. chinenesis were statistically significant at p < 0.05 level. Conclusion: The results demonstrated the toxicity, anti-diabetic and anti-inflammatory potential of the studied AgNPs. The synthesized nanoparticles of Odontosoria chinensis could be tested as an alternative to anticancer, anti-diabetic and anti-inflammatory drugs.

Annona Genus: Traditional Uses, Phytochemistry and Biological Activities.

Species from the Annona (Anonaceae) genus are used in traditional medicine for the treatment of various diseases. Ethnobotanical studies provide information regarding the plant part and the preparation method being used, while scientific studies such as in vitro, in vivo, and clinical tests can provide evidence supporting ethnopharmacological reports, directing studies towards the isolation of compounds which may be active for specific pathologies. Annona muricata and Annona squamosa were the most commonly reported species from those studied, with Annona cherimola and Annona classiflora also standing out. Acetogenins were the most commonly isolated metabolite class due to their cytotoxic properties, with flavonoids, alkaloids, steroids, and peptides also being reported. Many species from the Annona genus have proven biological activities, such as antitumor, antioxidant, antimicrobial and antifungal. The present review had as its objective to facilitate access to ethnobotanical, chemical and biological information in order to direct future researches.

Characterization, antibacterial activity and antibiotic modifying action of the Caryocar coriaceum Wittm. pulp and almond fixed oil.

In this study the physicochemical characterization of the pulp and almond fixed oil was carried out; their antibacterial activity and aminoglycoside antibiotic modifying action against standard and multiresistant Gram-positive and -negative bacteria were investigated using the broth microdilution assay. Physical properties such as moisture, pH, acidity, peroxide index, relative density and refractive index indicate stability and chemical quality of the oils. In the GC/MS chemical composition analysis, a high unsaturated fatty acid content and the presence of oleic and palmitic acids were observed in the oils. In the antibacterial assay, more significant results were obtained for Escherichia coli, while other standard and multi-resistant strains presented MIC values ≥ 1024 µg/mL. Furthermore, the fixed oils in association with antibiotics were able to significantly improve antibacterial activity against S. aureus with a reduction in MICs.