O objetivo com esta pesquisa foi avaliar a germinação e viabilidade dos diásporos de Myracrodruon urundeuva Allemão mantidas em geladeira, sob diferentes períodos e recipientes de armazenamento. O ...experimento foi instalado em delineamento inteiramente casualizado, com tratamentos sob arranjo fatorial 4 x 5, correspondendo, respectivamente aos quatro recipientes de armazenamento em geladeira (saco de papel, saco plástico, pote de vidro e garrafa plástica) e aos cinco períodos de acondicionamento (0, 90, 180, 270 e 360 dias), o qual inclui também as sementes recém-colhidas. Para cada período e recipiente de armazenamento, foram avaliadas as seguintes variáveis: teor de umidade, germinabilidade, índice de velocidade de germinação (IVG) e a sincronia da germinação das sementes. Os testes de germinação foram conduzidos em placas de Petri em câmara de germinação do tipo B.O.D., em quadruplicatas de 50 sementes cada, e avaliados durante 10 dias, para cada período de armazenamento. Os dados obtidos foram submetidos à análise de variância sendo as médias comparadas pelo teste de Tukey a 5 % de probabilidade. Os resultados evidenciaram que o teor de umidade das sementes não apresentou variação em nenhum dos tratamentos analisados. Observou-se que a porcentagem de germinação dos diásporos de M. urundeuva se manteve acima de 80% em todos os tempos e recipientes de armazenamento, sofrendo uma redução a partir dos 270 dias, em sementes armazenadas em saco plástico, pote de vidro e garrafa plástica. Verificou-se que, em todos os recipientes utilizados para acondicionamento, o IVG e a sincronia da germinação foram afetados em todos os tempos de armazenamento, quando comparado as sementes recém-colhidas. A melhor condição para conservação de sementes de M. urundeuva se deu com o acondicionamento em sacos de papel, por 360 dias, sem a perda da viabilidade.
Hancornia speciosa Gomes is a fruit and medicinal species used for treating infectious diseases of the genitourinary system. However, its mechanism of action against microbes is still not fully ...understood. Infections in the genitourinary system caused by Candida spp. are associated with its fungal resistance and pathogenicity. New plant-derived compounds are an alternative to fight these Candida infections.
The objective of this study was to evaluate the anti-Candida effects of extracts of the stem bark of H. speciosa. This research investigated the chemical composition of sulfuric ether (EEHS) and methanolic (MEHS) extracts, their drug-modifying action on fluconazole, and their anti-virulence action on the morphological transition of Candida species.
The extracts (EEHS and MEHS) of the stem bark of H. speciosa were chemically characterized via qualitative phytochemical screening and by liquid chromatography coupled with mass spectrometry (UPLC-MS-ESI-QTOF). The extracts were evaluated regarding their antifungal effects and fluconazole-modifying activity against Candida albicans, Candida krusei, and Candida tropicalis using the broth microdilution method. Additionally, the study evaluated the inhibition of fungal virulence in Candida species through morphological transition assays.
The phytochemical screening revealed the presence of anthocyanidins, anthocyanins, aurones, catechins, chalcones, flavones, flavonols, flavanones, leucoanthocyanidins, tannins (condensed and pyrogallic), and xanthones in both extracts of the stem bark of H. speciosa. The UPLC-MS-ESI-QTOF analysis identified the same compounds in both extracts, predominating phenolic compounds. Some compounds were first time recorded in this species: gluconic acid, cinchonain IIb, cinchonain Ib isomer, and lariciresinol hexoside isomers. Most of the intrinsic antifungal activity was observed for the MEHS against C. krusei (IC
: 58.41 μg/mL). At subinhibitory concentrations (MC/8), the EEHS enhanced the action of fluconazole against all Candida strains. The MEHS exhibited greater efficacy than fluconazole inhibiting C. krusei growth. The EEHS completely inhibited hyphae appearance and reduced pseudohyphae formation in C. albicans.
The stem bark of H. speciosa is a rich source of bioactive compounds, especially phenolic. Phenolic compounds can have important roles in fighting infectious diseases of the genitourinary system, such as candidiasis. The extracts of H. speciosa improved the action of the drug fluconazole against Candida species, inhibited hyphae appearance, and reduced pseudohyphae formation. The results of this study can support the development of new therapeutics against resistant strains of Candida.
Efflux pumps are proteins present in the plasma membrane of bacteria, which transport antibiotics and other compounds into the extracellular medium, conferring resistance. The discovery of natural ...efflux pump inhibitors is a promising alternative. α-Bisabolol is a sesquiterpene isolated from several plants such as
L. and has important properties such as antibacterial and anti-inflammatory activity. Currently, the formation of inclusion complexes with β-Cyclodextrin has been used for improving the physicochemical characteristics of the host molecule. This study evaluated the effect of α-Bisabolol, in isolation and in complexation with β-Cyclodextrin, as TetK and NorA efflux pump inhibitors in
strains. The minimum inhibitory concentration (MIC) was determined. Subsequently, inhibitory activity over the pumps was observed by an MIC reduction for the antibiotics, by using subinhibitory concentrations (MIC/8) in combination with tetracycline and norfloxacin. The MIC of the compounds was ≥1024 μg/mL. α-Bisabolol potentiated the action of tetracycline and reduced the MIC of norfloxacin to a clinically relevant concentration. The complexed substance showed synergism however, the effect of the isolated α-Bisabolol was superior to the complex. These results indicate α-Bisabolol is a potential substance to be used as an efflux pump inhibitor.
Spondias mombin
is used in the folk medicine for the treatment of diarrhea and dysentery, indicating that extracts obtained from this species may present pharmacological activities against pathogenic ...microorganisms. The purpose of this work was to investigate the chemical composition and evaluate the antimicrobial activity of extracts obtained from the leaves (aqueous) and bark (hydroethanolic) of
S. mombin
both as single treatments and in combination with conventional drugs. Following a qualitative chemical prospection, the extracts were analyzed by HPLC–DAD. The antimicrobial activities were evaluated by microdilution. The combined activity of drugs and extracts was verified by adding a subinhibitory concentration of the extract in the presence of variable drug concentrations. The Minimum Fungicidal Concentration (MFC) was determined by a subculture of the microdilution test, while the effect of the in vitro treatments on morphological transition was analyzed by subculture in moist chambers. While the qualitative analysis detected the presence of phenols and flavonoids, the HPLC analysis identified quercetin, caffeic acid, and catechin as major components in the leaf extract, whereas kaempferol and quercetin were found as major compounds in the bark extract. The extracts showed effective antibacterial activities only against the Gram-negative strains. With regard to the combined activity, the leaf extract potentiated the action of gentamicin and imipenem (against
Staphylococcus aureus
), while the bark extract potentiated the effect of norfloxacin (against
S. aureus
), imipenem (against
Escherichia coli
), and norfloxacin (against
Pseudomonas aeruginosa
). A more significant antifungal (fungistatic) effect was achieved with the bark extract (even though at high concentrations), which further enhanced the activity of fluconazole. The extracts also inhibited the emission of filaments by
Candida albicans
and
Candida tropicalis
. Together, these findings suggest that that the extract constituents may act by favoring the permeability of microbial cells to conventional drugs, as well as by affecting virulence mechanisms in
Candida strains
.
•The essential oil (EO) of D. ambrosioides presents anti-candidacy action.•The EO of D. ambrosioides has drug modulating action.•The EO of D. ambrosioides is able to inhibit free radicals.
The oil ...presented the α-Terpinene as the major compound with 54.09% presence. Antibacterial activity demonstrated significant MIC against Staphylococcus aureus (256 μg/mL) and moderate against Pseudomonas aeruginosa (512 μg/mL). The modulating effect of antibiotics was significant against P. aeruginosa potentiating the effect of all the antibiotics tested. The IC50 observed for CT LM 23 was clinically relevant (19.3 μg/mL), similar to that obtained for CA INCQS 40006 (25.2 μg/mL). The combined effect with fluconazole also showed significant results, 0.1 and 22.7 μg/mL, for CT LM 23 and CA INCQS 40006, respectively. For CA LM 77 the IC50 was 101.9 μg/mL and for CT INCQS 40042 a value of 53.3 μg/mL. Regarding the modulation, both were considered of clinical relevance, 3.3 and 6.4 μg/mL. OEDA has low antioxidant activity (>1024 μg/mL). Therefore, the popular use against infections was corroborated by this work.
The emergence of fungal resistance to commercial drugs has been a major problem for the WHO. In this context, research with natural products is promising in the discovery of new active substances. ...Thus, this work evaluated the antifungal effect of a medicinal plant (i.e.,
) against strains of the genus
, tested the combined effect with the drug fluconazole, and, finally, determined the phenolic constituents present in the species. Initially, aqueous extracts of leaves (AELMs) and aerial parts (AEAPMs) of the species were prepared. For microbiological assays, the minimum fungicidal concentration was determined by broth microdilution, and the combined effect of fluconazole extracts were verified by sub-inhibitory microdilution concentrations (CFM/8) followed by spectrophotometric readings which were used to determine the IC
. HPLC detected the presence of flavonoids and phenolic acids, detecting eight compounds present in the samples of which caffeic acid and quercetin were major components. The AELMs modulated fluconazole activity since it decreased fluconazole's IC
from 7.8 µg/mL to an IC
of 4.7 µg/mL (CA LM 77) and from 28.8 µg/mL to 18.26 µg/mL (CA INCQS 40006) for the
strains. The AEAPMs were able to potentiate the effect of fluconazole more effectively than the AELMs. Such an effect was significant for the 16 µg/mL concentration for CA LM 77 and 32 µg/mL for CA INCQS 40006. The AEAPMs as well as the AELMs presented clinically relevant activities for
strains. For the
LM 23 strain, the AEPMs obtained an IC
of 25 µg/mL and the AELMs an IC
of 359.9 µg/mL.
The barks of Anacardium occidentale (cashew tree) been used for centuries in the popular pharmacopoeia of South America and West Africa for the treatment of infections and neurodegenerative diseases. ...Thus, this work aimed to evaluate the biological effect of the ethanolic extract of the barks against strains of Candida spp. and cancer cell lines, as well as identifying the chemical constituents present in the product. For that, the extract was submitted to an UPLC-QTOF/MS, which mass fragments were compared in the literature at the botanical family level. For antifungal activity, the serial microdilution method was used in varying concentrations, and the modifier of fluconazole in sub-inhibitory concentrations (CFM/16). Cytotoxicity was evaluated using the MTT method 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazol bromide in five cell lines (HL-60, NCI–H292, HCT-116, P815 and L929). Eight compounds were identified, including gallic acid, luteolin, epicatechin gallate and agathisflavone. An antifungal effect of the extract was observed for the strains of Candida albicans, Candida krusei and Candida tropicalis, with IC50 lower than 400 μg/mL. In addition, there was a synergistic action with fluconazole against C. albicans and C. tropicalis. As for antitumor activity, there was a moderate activity against all cancer lines, showing low cytotoxicity for the normal line, making the extract an excellent candidate for drug development. The ethnopharmacological use of A. occidentale by populations for the treatment of DIP's and neurodegenerative diseases, reveal that this organ has biological actions against microorganisms that cause infections, as well as being capable of causing toxicity in cancer cells.
•The extract of the bark of A. occidentale has anti-Candida effect.•Anacardium occidentale has the ability to intensify the effect of the antifungal Fluconazole.•The barks of A. occidentale have phenolic acids, flavonoids and tannins.•The bark extract presented a greater cytotoxic activity over tumor cells.
This study aimed to evaluate the antibiotic effects of the fixed oils of Acrocomia aculeata (FOAA) and Syagrus cearenses (FOSC) against the bacterial strains and the fungi strains of the genus ...Candida spp. The method of serial microdilution using different concentrations was used for measuring the individual biological activity of the fixed oils. The fixed oil of A. aculeata showed the presence of oleic acid (24.36%), while the oil of S. cearensis displayed the content of myristic acid (18.29%), compounds detected in high concentration. The combination FOAA + Norfloxacin, and FOSC + Norfloxacin showed antibacterial activity against E. coli and S. aureus strains, demonstrating possible synergism and potentiation of the antibiotic action against multidrug-resistant strains. The combination FOAA + Fluconazole displayed a significant effect against Candida albicans (IC50 = 15.54), C. krusei (IC50 = 78.58), and C. tropicalis (IC50 = 1588 μg/mL). Regarding FOSC + Fluconazole, it was also observed their combined effect against the strains of C. albicans (IC50 = 3385 μg/mL), C. krusei (IC50 = 26.67 μg/mL), and C. tropicalis (IC50 = 1164 μg/mL). The findings of this study showed a significant synergism for both fixed oils tested when combined with the antibiotic.
•– Were identifed the presence of eight fatty acids in the FOAA and FOSC.•– Were observed high percentages of oleic acid in FOAA and myristic acid in FOSC.•- Significant synergism was observed when the fixed oils were associated with Norfloxacin.•- Significant synergism was observed when the fixed oils were associated with Fluconazole.
Infections by multiresistant microorganisms have led to a continuous investigation of substances acting as modifiers of this resistance. By following this approach, the chemical composition of the ...essential oil from Piper caldense leaf and its antimicrobial potential were investigated. The antimicrobial activity was determined by broth microdilution method providing values for minimum inhibitory concentration (MIC), IC50, and minimum fungicidal concentration (MFC). The essential oil was tested as a modulator for several antibiotics, and its effect on the morphology of Candida albicans (CA) strains was also investigated. The chemical characterization revealed an oil composed mainly of sesquiterpenes. Among them are caryophyllene oxide (13.9%), spathulenol (9.1%), δ-cadinene (7.6%) and bicyclogermacrene (6.7%) with the highest concentrations. The essential oil showed very low activity against the strains of CA with the lowest values for IC50 and MFC of 1790 μg/mL and 8192 μg/mL, respectively. The essential oil modulated the activity of fluconazole against CA URM 4387 strain, which was demonstrated by the lower IC50 obtained, 2.7 μg/mL, whereas fluconazole itself presented an IC50 of 7.76 μg/mL. No modulating effect was observed in the MFC bioassays. The effect on fungal morphology was observed for both CA INCQS 40006 and URM 4387 strains. The hyphae projection was completely inhibited at 4096 μg/mL and 2048 μg/mL, respectively. Thus, the oil has potential as an adjuvant in antimicrobial formulations.
This study aimed to evaluate the antibacterial and inhibitory action of NorA, Tet(K), MsrA and MepA efflux pumps in S. aureus strains using the sesquiterpenes named trans-caryophyllene and ...caryophyllene oxide, both isolated and encapsulated in liposomes. The antibacterial and inhibitory action of these efflux pumps was evaluated through the serial microdilution test in 96-well microplates. Each sesquiterpene and liposome/sesquiterpene was combined with antibiotics and ethidium bromide (EtBr). The antibiotics named norfloxacin, tetracycline and erythromycin were used. The 1199 B, IS-58, RN4220 and K2068 S. aureus strains carrying NorA, Tet(K), MsrA and MepA, respectively, were tested. In the fluorescence measurement test, K2068 S. aureus was incubated with the sesquiterpenes and EtBr, and the fluorescence emission by EtBr was measured. The tested substances did not show direct antibacterial activity, with MIC >1024 μg/mL. Nonetheless, the isolated trans-caryophyllene and caryophyllene oxide reduced the MIC of antibiotics and EtBr, indicating inhibition of NorA, Tet(K) and MsrA. In the fluorescence test, these same sesquiterpenes increased fluorescence emission, indicating inhibition of MepA. Therefore, the sesquiterpenes named trans-caryophyllene and caryophyllene oxide did not show direct antibacterial action; however, in their isolated form, they showed possible inhibitory action on NorA, Tet(K), MsrA and MepA efflux pumps. They may also act in antibiotic potentiation. Further studies are needed to identify the mechanisms involved in antibiotic potentiation and efflux pump inhibitory action.
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•Trans-Caryophyllene and caryophyllene oxide were encapsulated in liposomes.•Trans-Caryophyllene and caryophyllene oxide possibly inhibit NorA efflux pump (EP).•The sesquiterpenes possibly inhibit Tet(K), MsrA, and MepA efflux pumps.•Liposomal nanoformulations with sesquiterpenes showed no inhibitory action on EPs.
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