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1.
J Chromatogr A ; 1732: 465208, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39088897

RESUMO

Piper gaudichaudianum Kunth essential oil (EO) is a natural source of bioactive components, having multiple therapeutic applications. Its chemical composition is highly variable, and strictly depends on abiotic factors, resulting in various biological activities. The present study details the utilization of multiple gas chromatographic techniques alongside nuclear magnetic resonance (NMR) spectroscopy to characterize the essential oil of Piper gaudichaudianum Kunth from Brazil. Seventy-six components were identified using GC-MS analysis, while enantio­selective multidimensional gas chromatography elucidated the enantiomeric distribution of eight chiral components, for the first time in the literature. Following GC-MS analysis, an unidentified component, constituting approximately 27 % of the total oil, prompted an isolation step through preparative gas chromatography. Through the combined use of nuclear magnetic resonance, GC-Fourier transform infrared spectroscopy (FTIR), and mass spectrometry (MS), the unknown molecule was structurally identified as 4-[(3E)­dec-3-en-1-yl]phenol. Remarkably, it was identified as a known molecule, gibbilimbol B, and not previously listed in any MS database. Subsequently, the spectrum was included in a commercial library, specifically the FFNSC 4.0 MS database, for the first time.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Óleos Voláteis , Piper , Piper/química , Óleos Voláteis/química , Óleos Voláteis/análise , Brasil , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Óleos de Plantas/química , Cromatografia Gasosa/métodos
2.
Plants (Basel) ; 12(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37111810

RESUMO

Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus are the primary bacteria that cause clinical infections, such as urinary and intestinal infections, pneumonia, endocarditis, and sepsis. Bacterial resistance is an innate natural occurrence in microorganisms, resulting from mutations or the lateral exchange of genetic material. This serves as evidence for the association between drug consumption and pathogen resistance. Evidence has demonstrated that the association between conventional antibiotics and natural products is a promising pharmacological strategy to overcome resistance mechanisms. Considering the large body of research demonstrating the significant antimicrobial activities of Schinus terebinthifolius Raddi, the present study aimed to evaluate the chemical composition and antibiotic-enhancing effects of Schinus terebinthifolius Raddi essential oil (STEO) against the standard and multidrug-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The STEO was extracted by hydrodistillation using a Clevenger-type vacuum rotary evaporator. The Minimum Inhibitory Concentration (MIC) of the STEO was assessed by the microdilution method to evaluate the antibacterial activity. The antibiotic-enhancing activity of the essential oil was assessed by determining the MIC of antibiotics in the presence of a sub-inhibitory concentration (MIC/8) of the natural product. The GC-MS analysis revealed alpha-pinene (24.3%), gamma-muurolene (16.6%), and myrcene (13.7%) as major constituents of the STEO. The STEO potentiated the enhanced antibacterial activity of norfloxacin and gentamicin against all the strains and increased the action of penicillin against the Gram-negative strains. Therefore, it is concluded that although the STEO does not exhibit clinically effective antibacterial activity, its association with conventional antibiotics results in enhanced antibiotic activity.

3.
Bol. latinoam. Caribe plantas med. aromát ; 21(4): 548-560, jul. 2022. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1527072

RESUMO

Yerba mate ( Ilex paraguariensis ) produces several secondary metabolites of interest to the phar maceutical industry, such as chlorogenic acids and methylxanthines. These compounds have been produced in vitro by callus culture from different species. However, for I. paraguariensis , no studies upon the production of these compounds in vitro have been p erformed to date. In this work, we show that the concentration of secondary metabolites from I. paraguariensis callus is possible and highly dependent on the callus growth phase. We observed that the best phase for the production of secondary compounds in calli of yerba mate is the stationary growth phase on both genotypes tested. In this phase, higher levels of phenolic compounds, chlorogenic acid and 3,5 - dicaffeoylquinic acid and greater antioxidant activity were observed. Chlorogenic acid and 3,5 - dicaffe oylquinic acid presented positive correlation with antioxidant activity. For the first time, secondary compounds were reported in yerba mate calli cultivated in vitro .


La yerba mate ( Ilex paraguariensis ) produce varios metabolitos secundarios de interés para la industria farmacéutica, como los ácidos clorogénicos y las metilxantinas. Estos compuestos se han producido in vitro mediante cultivo de ca llos de diferentes especies. Sin embargo, para I. paraguariensis , hasta la fecha no se han realizado estudios sobre la producción de estos compuestos in vitro . En este trabajo, mostramos que la concentración de metabolitos secundarios desde callos de I. pa raguariensis es posible y altamente dependiente de la fase de crecimiento del callo. Observamos que la mejor fase para la producción de compuestos secundarios en callos de yerba mate es la fase de crecimiento estacionario en ambos genotipos probados. En es ta fase se observaron niveles más altos de compuestos fenólicos, ácido clorogénico y ácido 3,5 - dicafeoilquínico y una mayor actividad antioxidante. El ácido clorogénico y el ácido 3,5 - dicafeoilquínico presentaron correlación positiva con la actividad antio xidante. Por primera vez, se reportaron compuestos secundarios en callos de yerba mate cultivados in vitro .


Assuntos
Ilex paraguariensis/crescimento & desenvolvimento , Ilex paraguariensis/química , Compostos Fenólicos , Antioxidantes/análise , Xantinas/análise , Cromatografia Líquida de Alta Pressão
4.
Semina ciênc. agrar ; 43(3): 1373-1394, maio.-jun. 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1369587

RESUMO

Hop (Humulus lupulus L.) female inflorescences are important raw materials used to produce beers, cosmetics, and medicines. Vegetative propagation is the preferred way of obtaining seedlings for commercial cultivations as female plants produce more lupulin than male plants, a component of commercial interest. It can be carried out by macropropagation (stem cuttings or rhizomes) or micropropagation. This review aimed to systematize different techniques of hop vegetative propagation, with no time frame, from searches in the main academic research bases: Capes Journal Portal, Scielo, Scopus, Web of Science, Science Direct, Google Scholar, and ResearchGate. Most studies are related to micropropagation, mainly addressing different plant regulators and concentrations, as well as types of explants and culture media, strategies to produce virus-free plants, artificial lighting, and cryopreservation. Experiments with stem cuttings are more common regarding macropropagation, but factors such as size and origin of cuttings, rooting period, and the response of different cultivars need to be better evaluated. Cultivation by cuttings allows the production of clones of female plants and micropropagation the production of virus-free clones in a short time and less physical space. Currently, micropropagation has been widely applied to cryopreservation.(AU)


As inflorescências femininas do lúpulo (Humulus lupulus L.) são matérias-primas importantes utilizadas na produção de cervejas, cosméticos e medicamentos. Como as plantas femininas produzem mais lupulina que as masculinas, componente de interesse comercial, a propagação vegetativa é a forma preferencial de obtenção de mudas para os cultivos comerciais. Esta pode ser realizada por macropropagação (estaquia caulinar ou rizomas) ou micropropagação. O objetivo desta revisão foi sistematizar as diferentes técnicas de propagação vegetativa do lúpulo, sem recorte temporal, a partir de buscas nas principais bases de pesquisa acadêmica: Portal de Periódicos Capes, Scielo, Scopus, Web of Science, Science Direct, Google Acadêmico e Research Gate. A maioria dos trabalhos são relacionados à micropropagação, abordando principalmente diferentes reguladores vegetais e concentrações, além de tipos de explantes e meios de cultura, estratégias para produzir plantas livres de vírus, iluminação artificial e criopreservação. Quanto à macropropagação, experimentos com estaquia caulinar são mais comuns, porém fatores precisam ser melhor avaliados tais como tamanho e origem das estacas, período de enraizamento e resposta de diferentes cultivares. O cultivo por estacas permite a produção de clones de plantas femininas e a micropropagação a produção de clones isentos de vírus, em pouco tempo e em menor espaço físico. Atualmente, a micropropagação tem sido muito aplicada à criopreservação.(AU)


Assuntos
Humulus/crescimento & desenvolvimento , Rizoma , Inflorescência , Cannabaceae/crescimento & desenvolvimento , História
5.
An Acad Bras Cienc ; 93(1): e20181299, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909815

RESUMO

Eugenia uniflora, known as the "Brazilian cherry", is an economically important neotropical Myrtaceae in the cosmetics and pharmaceutical industries due the production of essential oils with antioxidant activity. On account of its significant genetic variability, genotype evaluations are needed in order to identify genetic features related to the essential oil production that meet the industry requirements. The main objective of the present study was to evaluate the yield, composition, and antioxidant activity of essential oils isolated from the leaves of 36 genotypes of E. uniflora. Essential oil samples were obtained by hydrodistillation, and their composition was determined by gas chromatography coupled with mass spectrometry. A variation of 0.22% to 1.68% in the essential oil yield was observed, in which 78 compounds, namely oxygenated sesquiterpenes, were identified. According to the cluster analysis of the major compounds, six groups were revealed. The observed diversity demonstrates the genetic variability of the species. Also, the antioxidant activity was affected by the composition of the essential oils, ranging from 176.66 to 867.57 µM TEAC.


Assuntos
Eugenia , Óleos Voláteis , Antioxidantes , Brasil , Eugenia/genética , Cromatografia Gasosa-Espectrometria de Massas , Genótipo , Folhas de Planta
6.
Arch Microbiol ; 203(6): 3077-3087, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33787988

RESUMO

This study aimed to investigate the chemical composition and antifungal potential of the essential oil of Baccharis trimera (Less.) DC. against Candida strains. The half maximal inhibitory concentration (IC50) was assessed by the microdilution method using the essential oil at a concentration range of 8192 to 8 µg/mL. The minimum fungicide concentration (MFC) was determined by subculture in solid medium. The ability of the essential oil to modulate the activity of antifungals was determined in wells treated simultaneously with the oil at a subinhibitory concentration (MFC/16) and fluconazole (FCZ). The fungal morphology was analyzed by microscopy. Gas chromatography coupled with mass spectrometry (GC/MS) was used to identify the chemical composition. The essential oil presented an CI50 of 11.24 and 1.45 µg/mL, which was found to potentiate the effect of FCZ against Candida albicans. On the other hand, this combined treatment resulted in antagonism against Candida tropicalis and no evident modulation against Candida krusei was observed. The essential oil significantly inhibited hyphae growth. However, with a MFC ≥ 16,384 µg/mL, it is assumed that it has a fungistatic action. The antifungal properties demonstrated in this study might be related to the presence of sesquiterpenes and monoterpenes, and the interaction between them. In conclusion, Baccharis trimera showed promising anti-Candida effects, in addition to potentiating the activity of FCZ against Candida albicans, affecting its morphological transition. Therefore, this species constitutes a source of chemical compounds with the potential to be used in the combat of fungal infections.


Assuntos
Baccharis , Candida , Óleos Voláteis , Antifúngicos/farmacologia , Baccharis/química , Candida/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Pichia/efeitos dos fármacos
7.
Acta Trop ; 217: 105869, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33631121

RESUMO

Haemonchus contortus, a blood-sucking parasite of small ruminants, produces very important economic losses in the productive sector. This abomasum parasite has become resistant to most commercial drugs worldwide, and alternatives to fight this problem are urgently needed. Essential oils (EO) are a complex mixture of volatile secondary metabolites, composed mainly by terpenoids and phenolic compounds, from plants that have several pharmacological properties, including anthelmintic activity. Particularly, citrus peel is a source of cold-pressed EO, where limonene is its major component, and can be used as an additional food component for ruminants. The aim of the present work was to determine the in vitro anthelmintic activity of EO from Citrus bergamia (EOB), C. x paradisii (EOG) and limonene against the benzimidazole-susceptible Kirby isolate of H. contortus, using the egg hatch test (EHT) and the exsheathed third stage larval motility test (XLMT) using a WMicroTracker equipment. Albendazole (ABZ) and monepantel (MON) were used as positive controls. The 50% inhibitory concentrations (IC50) in XLMT were 8.77 and 13.88 µg/ml for EOB and EOG respectively, after an incubation of 72 h. An interesting observation on XLMT resulted when the positive controls were tested on the same plate, but in different well of the EOB. The volatile components of the EO significantly influenced (P < 0.05) the percentage of larval motility, reducing values from 66.9 to 19.6% for ABZ, and from 72.8 to 33.7% for MON, when comparing the activity of positive controls in a control plate without EO. The in vitro anthelmintic activity of EOB and EOG shows that they could be interesting candidates for nematode control. It is still necessary additional studies against the adult stage of H. contortus in efficacy trials in infected animals to validate their anthelmintic activity.


Assuntos
Anti-Helmínticos/farmacologia , Citrus/química , Haemonchus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Larva/efeitos dos fármacos
8.
Vet Parasitol ; 289: 109317, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33246235

RESUMO

Parasitic diseases caused by gastrointestinal nematodes (GIN) are responsible for a major impact on ruminant welfare. Although the available anthelmintics have a safe margin of toxicity to the animals, their indiscriminate use has increased the selection of resistant parasite populations. In this scenario, essential oils (EO) stand out as a promising ecofriendly therapeutic alternative against GIN. The objective of this work was to determine the effect of the EO of Mentha villosa Hubs (MVEO) collected in 2017 and 2018, M. x piperita (MPEO) and their main components, carvone and limonene, against the third stage larvae (L3) of Haemonchus spp. and Trichostrongylus spp. The solutions, including in nanoemulsion preparations, were tested in a range of concentrations using the larval migration inhibition test (LMIT). The EO and carvone were also tested in combination with nitroxynil (NTX) to determine their effect as drug enhancers (additive or synergy). MVEO/2017, MVEO/2018, MPEO and carvone showed 70.6 (73.4 mg/mL), 86.3 (74.9 mL/mL), 95.5 (143.6 mg/mL), and 88.2 % (38.3 mg/mL) efficacy against L3, respectively. Carvone alone had approximately a 3-fold higher efficacy when compared to its concentration in each EO: 68.8 % in MVEO/2017 and 83.9 % in MVEO/2018. Limonene did not show any significant effect on inhibiting L3 migration. The combination of MPEO and NTX, and carvone and NTX showed a statistically significantly (P <  0.05) synergic and additive effect, respectively, when compared to the isolated treatment. The nanoemulsion of MVEO/2017 at 0.367 mg/mL, inhibited L3 migration by 83.1 %, demonstrating to be highly effective (concentration ratio of 1:0.004), when compared to the MVEO/2017 (70.6 % at 73.4 mg/mL) extraction. The in vitro data from the combination of MPEO or carvone plus NTX suggest that these products can be considered for in vivo experiments against the most important GIN of ruminants as drug enhancers, possibly reducing the final concentration of NTX`. The efficacy of carvone was higher (EC50 = 1.96 mg/mL) than its expected efficacy, based on its concentrations on both EO. Therefore, this component does not need the entire EO composition to exert its L3 motility action. The remarkable efficacy demonstrated by the MVEO/2017/nanoemulsion (EC50 = 0.10 mg/mL), supports its potential to be a candidate to the next-generation therapy to alleviate clinical parasite infections and combat GIN resistant populations.


Assuntos
Anti-Helmínticos/farmacologia , Mentha/química , Nematoides/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Óleos de Plantas/farmacologia , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/química , Monoterpenos Cicloexânicos/administração & dosagem , Monoterpenos Cicloexânicos/química , Monoterpenos Cicloexânicos/farmacologia , Sinergismo Farmacológico , Quimioterapia Combinada , Limoneno/administração & dosagem , Limoneno/química , Limoneno/farmacologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Nitroxinila/administração & dosagem , Nitroxinila/química , Nitroxinila/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/química , Óleos de Plantas/química , Ovinos , Doenças dos Ovinos/parasitologia
9.
Braz. arch. biol. technol ; 64: e21190253, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153292

RESUMO

HIGHLIGHTS Essential oils from populations of B. dracunculifolia were investigated. β-pinene and (E)-nerolidol were the main compounds in B. dracunculifolia populations. The difference in the chemical profile of the essential oils is quantitative only. There is a negative correlation between the antioxidant activity and spathulenol.


Abstract Baccharis dracunculifolia DC. is a Brazilian native plant, presenting wide chemical diversity and numerous pharmaceutical and industrial applications. This research assessed the yield, antioxidant activity and the chemical similarity of essential oils from 10 populations of B. dracunculifolia in the state of Paraná, southern Brazil. The extraction of the volatile compounds was carried out by hydrodistillation, the chemical composition was determined by GC/FID and GC/MS and the antioxidant activity by the DPPH method. The essential oil yield of wild B. dracunculifolia populations ranged from 0.14 to 0.87%. The oils were predominantly composed of oxygenated sesquiterpenes (34.16 - 51.01%), monoterpene hydrocarbons (18.02 - 46.17%) and sesquiterpenes hydrocarbons (9.60 - 17.70%). The major compounds found in all populations were β-pinene (7.65 - 29.8%) and (E)-nerolidol (9.11 - 21.68%). Essential oil solutions (20%) from different populations presented antioxidant capacity ranging from 27.78 to 91.67%. A negative correlation was found between the antioxidant activity and spathulenol (r = -0.696). Multivariate analyses separated the populations into three groups: (1) low concentrations of α-pinene (2.02 - 2.06%), (2) high concentrations of α-pinene (4.17 - 4.61%) and β-pinene (22.54 - 29.80%), and (3) intermediate concentrations of α-pinene (2.38 - 3.31%), β-pinene (12.77 - 19.03%) and spathulenol (6.02 - 9.06%).


Assuntos
Óleos de Plantas/química , Óleos Voláteis/química , Baccharis/química , Antioxidantes/química , Plantas Medicinais/química , Óleos de Plantas/isolamento & purificação , Brasil , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/isolamento & purificação
10.
An Acad Bras Cienc ; 92(3): e20181251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206796

RESUMO

Ilex paraguariensis (yerba mate) is a native species from South America and is a rich source of bioactive compounds. There is a lack of research efforts on the phytochemical investigation of callus culture from this species. In the present study, an effort was made to optimize callus culture conditions and to identify secondary compounds. Calli were induced from 10 genotypes using leaf explants and the best genotype was selected to evaluate the effects of cytokinin types and concentrations on callus induction and biomass accumulation. The best genotype and cytokinin treatment were used to conduct one last experiment with sucrose concentrations in culture media and its effects on calli biomass, antioxidant activity and secondary compounds accumulation. Callus initiation was genotype dependent, and the 6-156-6 line had the best response. Zeatin supplemented medium showed higher callus induction rate (82%) and higher biomass accumulation after 120 days (328.2 mg). Higher biomass and secondary compounds accumulation were observed for calli on 3% sucrose medium. Antioxidant activity was not affected by sucrose concentrations. Yerba mate callus culture allowed the accumulation of chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, theobromine and caffeine.


Assuntos
Ilex paraguariensis , Genótipo , Extratos Vegetais , Folhas de Planta , América do Sul
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