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1.
Int J Biol Macromol ; 268(Pt 1): 131661, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38641286

RESUMO

In this study, two nanoemulsions were formulated with essential oil (EO) of Ocimum gratissimum with (EON) or without (EOE) cashew gum (CG). Subsequently, inhibition of melanosis and preservation of the quality of shrimp stored for 16 days at 4 ± 0.5 °C were evaluated. A computational approach was performed to predict the system interactions. Dynamic light scattering (DLS) and atomic force microscopy (AFM) were used for nanoparticle analysis. Gas chromatography and flame ionization detector (GC-FID) determined the chemical composition of the EO constituents. Shrimps were evaluated according to melanosis's appearance, psychrotrophic bacteria's count, pH, total volatile basic nitrogen, and thiobarbituric acid reactive substances. EON exhibited a particle size three times smaller than EOE. The shrimp treated with EON showed a more pronounced sensory inhibition of melanosis, which was considered mild by the 16th day. Meanwhile, in the other groups, melanosis was moderate (EOE) or severe (untreated group). Both EON and EOE treatments exhibited inhibition of psychrotrophic bacteria and demonstrated the potential to prevent lipid oxidation, thus extending the shelf life compared to untreated fresh shrimp. EON with cashew gum, seems more promising due to its physicochemical characteristics and superior sensory performance in inhibiting melanosis during shrimp preservation.


Assuntos
Anacardium , Ocimum , Óleos Voláteis , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Ocimum/química , Anacardium/química , Penaeidae/química , Gomas Vegetais/química , Conservação de Alimentos/métodos
2.
J Ethnopharmacol ; 309: 116348, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-36894109

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Egletes viscosa (L.) (macela) is a native wild herb that can be found in different states of northeastern Brazil. The infusions of its flower buds are traditionally used for the treatment of gastrointestinal disorders. E. viscosa possesses two chemotypes (named A and B), distinguishable by the composition of the essential oil from the flower buds. Although there are previous studies of the gastroprotective effect of the isolated constituents of E. viscosa, its infusions have not been investigated yet. AIM OF THE STUDY: The present study aimed to evaluate and compare the chemical composition and the gastroprotective effect of flower bud infusions of E. viscosa from chemotype A (EVCA) and chemotype B (EVCB). MATERIALS AND METHODS: Sixteen infusions were brewed with flower buds according to the traditional preparation mode and were analyzed through a UPLC-QTOF-MS/MS based metabolomic approach for determination of their metabolic fingerprints and quantification of bioactive compounds. Afterward, these data were analyzed by chemometric methods (OPLS-DA) for discrimination of the two chemotypes. Additionally, infusions of EVCA and EVCB (50, 100 and 200 mg/kg, p.o.) were evaluated on gastric ulcers induced by absolute ethanol (96%, 0.2 mL, p.o.) in mice. To elucidate the gastroprotective mechanisms, the effect of EVCA and EVCB on gastric acid secretion and gastric wall mucus was determined and the role of TRPV1 channels, prostaglandins, nitric oxide and KATP channels were assessed. Moreover, the oxidative stress-related parameters and the histological aspects of the stomach tissue were analyzed. RESULTS: The chemotypes can be discriminated from each other using UPLC-QTOF-MS/MS chemical fingerprints. Both chemotypes presented similar chemical compositions, consisting basically of caffeic acid derivatives, flavonoids and diterpenes. The quantification of bioactive compounds demonstrated that chemotype A possesses more ternatin, tanabalin and centipedic than chemotype B. EVCA and EVCB (50, 100 and 200 mg/kg, p.o.) significantly decreased the severity of ethanol-induced gastric lesions, as shown by a reduction in histological alterations and leucocyte infiltration in gastric tissue. The gastroprotective mechanism of both infusions involves an antioxidant effect, maintenance of gastric mucus and reduction gastric secretion. Stimulation of endogenous prostaglandins and nitric oxide release, activation of TRPV1 channels, and KATP channels are also involved in the gastroprotection of the infusions. CONCLUSION: The gastroprotective effect of EVCA and EVCB was equivalent and mediated through antioxidant and antisecretory actions, including the activation of TRPV1 receptors, stimulation of endogenous prostaglandins and nitric oxide, and opening of KATP channels. The presence of caffeic acid derivatives, flavonoids and diterpenes in both infusions is involved in mediating this protective effect. Our findings support the traditional use of infusions of E. viscosa for gastric disorders regardless of the chemotype.


Assuntos
Antiulcerosos , Diterpenos , Úlcera Gástrica , Camundongos , Animais , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/prevenção & controle , Etanol/farmacologia , Espectrometria de Massas em Tandem , Óxido Nítrico/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Antioxidantes/farmacologia , Prostaglandinas/metabolismo , Diterpenos/farmacologia , Flavonoides/farmacologia , Trifosfato de Adenosina/metabolismo , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Mucosa Gástrica
3.
J Pharm Biomed Anal ; 199: 114061, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33845386

RESUMO

Hippeastrum elegans is an Amaryllidaceae species producing alkaloids with pharmaceutical potential including lycorine and galanthamine. Herein, we developed a non-targeted metabolomic study associated to chemometrics and biological evaluations to identify the H. elegans constituents that were able to reduce the human neutrophils proinflammatory mechanisms. The alkaloid fractions were extracted from bulbs cultivated for 15 months (m) and harvested in six harvest periods (5, 7, 9, 11, 13, and 15 m). The GC-MS analysis allowed the detection of 41 alkaloids being 31 identified. All alkaloid components varied over the cultivation and most of them were lycorine-type skeletons. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) distinguished three groups according to the chemical profile (group I: 5, 7, and 9 m; group II: 11 m and group III: 13 and 15 m). Therefore, the biological assays were only performed with one of the representative samples of each group: 7 m, 11 m and 15 m. None of them was toxic to human neutrophils by LDH activity and MTT test. The 7 m and 15 m-alkaloid fractions showed anti-inflammatory effects by reducing human neutrophil degranulation. However, the former one was more effective in inhibiting the cell activation based on the reduction of myeloperoxidase (MPO) release and reactive oxygen species (ROS) production. Afterwards, Partial Least Squares analysis (PLS) indicated lycorine and 11,12-dehydro-2-methoxy-assoanine as the compounds responsible for the anti-inflammatory activity of the bioactive fraction. Thus, the 7 m-alkaloid fraction of H. elegans seems to be a promising anti-inflammatory drug that deserves additional research.


Assuntos
Alcaloides , Alcaloides de Amaryllidaceae , Amaryllidaceae , Alcaloides de Amaryllidaceae/farmacologia , Anti-Inflamatórios/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Neutrófilos , Extratos Vegetais
4.
Mem Inst Oswaldo Cruz ; 112(6): 458-468, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28591408

RESUMO

BACKGROUND: Dengue fever may present hemorrhages and cavitary effusions as result of exacerbated immune responses. We investigated hydro-alcoholic extracts from leaves (UGL) and bark (UGB) of the medicinal species Uncaria guinanensis with respect to antiviral effects in Dengue virus (DENV) infection and in immunological parameters associated with in vivo physiopathological features. METHODS: Chemical profiles from UGB or UGL were compared in thin layer chromatography and 1H nuclear magnetic resonance using flavonoid compounds and a pentacyclic oxindole alkaloid-enriched fraction as references. DENV-2-infected hepatocytes (Huh-7) were treated with extracts. Cell viability, DENV antigens and immunological factors were detected by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. FINDINGS: The UGL mainly differed from UGB by selectively containing the flavonoid kaempferitrin. UGB and UGL improved hepatocyte viability. Both extracts reduced intracellular viral antigen and inhibited the secretion of viral non-structural protein (NS1), which is indicative of viral replication. Reduction in secretion of macrophage migration inhibitory factor was achieved by UGB, of interleukin-6 by UGL, and of interleukin-8 by both UGB and UGL. MAIN. CONCLUSIONS: The U. guianensis extracts presented, antiviral and immunomodulatory effects for DENV and possibly a hepatocyte-protective activity. Further studies may be performed to consider these products as potential candidates for the development of an herbal product for the future treatment of dengue.


Assuntos
Antivirais/farmacologia , Quimiocinas/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Vírus da Dengue/efeitos dos fármacos , Dengue/virologia , Extratos Vegetais/farmacologia , Uncaria/química , Antígenos Virais/efeitos dos fármacos , Antígenos Virais/imunologia , Sobrevivência Celular/efeitos dos fármacos , Quimiocinas/imunologia , Citocinas/imunologia , Dengue/imunologia , Dengue/fisiopatologia , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos
5.
Mem. Inst. Oswaldo Cruz ; 112(6): 458-468, June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841802

RESUMO

ABSTRACT BACKGROUND Dengue fever may present hemorrhages and cavitary effusions as result of exacerbated immune responses. We investigated hydro-alcoholic extracts from leaves (UGL) and bark (UGB) of the medicinal species Uncaria guinanensis with respect to antiviral effects in Dengue virus (DENV) infection and in immunological parameters associated with in vivo physiopathological features. METHODS Chemical profiles from UGB or UGL were compared in thin layer chromatography and 1H nuclear magnetic resonance using flavonoid compounds and a pentacyclic oxindole alkaloid-enriched fraction as references. DENV-2-infected hepatocytes (Huh-7) were treated with extracts. Cell viability, DENV antigens and immunological factors were detected by enzyme-linked immunosorbent assay (ELISA) or flow cytometry. FINDINGS The UGL mainly differed from UGB by selectively containing the flavonoid kaempferitrin. UGB and UGL improved hepatocyte viability. Both extracts reduced intracellular viral antigen and inhibited the secretion of viral non-structural protein (NS1), which is indicative of viral replication. Reduction in secretion of macrophage migration inhibitory factor was achieved by UGB, of interleukin-6 by UGL, and of interleukin-8 by both UGB and UGL. MAIN CONCLUSIONS The U. guianensis extracts presented, antiviral and immunomodulatory effects for DENV and possibly a hepatocyte-protective activity. Further studies may be performed to consider these products as potential candidates for the development of an herbal product for the future treatment of dengue.


Assuntos
Humanos , Antivirais/farmacologia , Extratos Vegetais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Citocinas/imunologia , Quimiocinas/efeitos dos fármacos , Quimiocinas/imunologia , Uncaria/química , Dengue/fisiopatologia , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/efeitos dos fármacos , Vírus da Dengue/imunologia , Antígenos Virais/efeitos dos fármacos , Antígenos Virais/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo
6.
Planta Med ; 82(16): 1431-1437, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27336315

RESUMO

Coumarin, o-coumaric, and kaurenoic acid are bioactive compounds usually found in the leaves of Mikania laevigata. Genetic and environmental variations in the secondary metabolites of plants may have implications for their biological effects. Three different accessions of M. laevigata cultivated in four sites between the Equator and the Tropic of Capricorn in Brazil were evaluated aiming to present potential raw materials and discuss relationships among these three bioactive compounds. The results revealed effects of plant accessions and environmental factors and suggested two contrasting chemical phenotypes of M. laevigata. The first phenotype presented the highest levels of kaurenoic acid (2283 ± 316 mg/100 g) besides lower levels of coumarin (716 ± 61 mg/100 g), which was also stimulated by the environment and mild climate at the site nearest to the Tropic of Capricorn. The other phenotype presented the lowest levels of kaurenoic acid (137 ± 17 mg/100 g) besides higher levels of coumarin (1362 ± 108 mg/100 g), which was also stimulated by the environment and tropical climate at the site nearest to the Equatorial beach.


Assuntos
Cumarínicos/análise , Diterpenos/análise , Mikania/química , Ácidos Cumáricos/análise , Meio Ambiente , Fenótipo
7.
Braz. j. microbiol ; 45(2): 699-705, Apr.-June 2014. tab
Artigo em Inglês | LILACS | ID: lil-723136

RESUMO

The objective of this study was to evaluate the antimicrobial potential of Lippia alba essential oil (EOLa) and to investigate the effect of food ingredients on its efficacy. The antimicrobial potential of the oil was determined by the presence or absence of inhibition zones, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Escherichia coli, Listeria innocua, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella choleraesuis and Staphylococcus aureus. The effect of food ingredients and the pH on the antimicrobial efficacy of oil was assessed by monitoring the maximum growth rate of Listeria monocytogenes in model media. The model media included potato starch (0, 1, 5 or 10%), beef extract (1, 5, 3, 6 or 12%), sunflower oil (0, 5 or 10%) and TSB broth at pH levels of 4, 5, 6 or 7. The EOLa showed efficacy at all concentrations (50%, 25%, 6.25%, 3%, 1.5%, 0.8%, 0.4% and 0.2%) evaluated, against all bacterial species, Gram-positive and Gram-negative. The antimicrobial efficacy of EO was found to be a function of ingredient manipulation. Proteins and lipids had a negative impact on the oil effectiveness, indicating the protective action of both on the microbial specie tested. On the contrary, at the highest concentration of starch (10%), the lower rate growth of L. monocytogenes was detected, therefore indicating a positive effect of carbohydrates on the oil effectivenes. Regarding the pH, the studies showed that the rate of microbial growth increased with increasing pH. It was concluded that the use of EOLa is more effective control pathogenic and spoilage bacteria when applied to starchy foods under an acidic pH.


Assuntos
Antibacterianos/farmacologia , Interações Medicamentosas , Análise de Alimentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lippia/química , Óleos Voláteis/farmacologia , Antibacterianos/isolamento & purificação , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação
8.
Ciênc. agrotec., (Impr.) ; 32(1): 11-16, jan.-fev. 2008. tab
Artigo em Português | LILACS | ID: lil-479090

RESUMO

Conduziu-se este trabalho, com o objetivo de introduzir e avaliar 40 genótipos de cafeeiros das espécies Coffea arabica e Coffea canephora nas condições edafoclimáticas do Estado do Acre, visando disponibilizar aos cafeicultores acreanos, cultivares com melhor potencial produtivo. Da espécie C. arabica foram avaliados genótipos das cultivares Icatu, Bourbon, Mundo Novo, Catuaí, Obatã e Catimor. Da espécie C. canephora foram avaliadas as cultivares Conilon e Robusta, caracterizadas como Grupo Robusta. Os genótipos utilizados foram provenientes do Instituto Agronômico de Campinas (IAC) e da Embrapa Rondônia. O experimento foi conduzido no Campo Experimental da Embrapa Acre, Rio Branco, AC, no período de 1995 a 2004. O delineamento experimental foi em blocos casualizados com cinco repetições. As características avaliadas foram: produtividade, altura, diâmetro da copa e vigor. Da espécie C. arabica, grupo Icatu, destacou-se Icatu-PR-182039-1(IAC H 4782-7-788) com produtividade média de café beneficiado de 34 sc/ ha, Icatu IAC-4041; Icatu IAC-2945; Icatu IAC-2944-MT; Icatu IAC-4040 e Icatu IAC-4046 com produtividade variando de 20 a 26 sacas. Para o grupo Catuaí os melhores genótipos foram Obatã IAC 4275, Obatã IAC 1169 e Catimor IAC 4466 com produtividade média de café beneficiado de 49, 45 e 37 sacas por hectare respectivamente. Na espécie C. canephora foram avaliados 8 genótipos das cultivares Conilon e Robusta e quanto à produtividade não houve diferença estatística, observou-se incremento de 7 sacas/ha para a variedade Conilon IAC 66-3 quando comparado ao Conilon plantado na região. Nesta espécie os genótipos apresentaram sintomas de deficiência hídrica na época seca (julho/agosto).


This work aimed to introduce and evaluate 40 coffee genotypes of Coffea arabica e Coffea canephora species in soil and weather conditions of Acre and had as main goal to provide cultivars to coffee producers with better potential of production. It was evaluated the genotypes Icatu, Bourbon, Mundo Novo, Catuaí, Obatã e Catimor from Coffea arabica species and genotypes Conilon and Robusta from Coffea canephora species. The genotypes were originated from Instituto Agronômico de Campinas (IAC) and Embrapa Rondônia. The study was carried out in the experimental field of Embrapa Acre, Rio Branco, AC from 1995 to 2004 following a randomized block design, with 5 replicates. One studied characteristics such as yield, height, plant diameter and vigor. The best genotype of Coffea arabica species, Icatu group, showed to be the Icatu-PR-182039-1(IAC H 4782-7-788), which yielded 34 sacks/ha of clean coffee; right after came Icatu IAC-4041, Icatu IAC-2945, Icatu IAC-2944-MT, Icatu IAC- 4040 and Icatu IAC-4046 with mean yeld from 20 to 26 sacks. For Catuai group, the best genotypes were Obatã IAC 4275, Obatã IAC 1169 e Catimor IAC 4466 with mean yield of 49, 45 e 37 sacks per hectare of clean coffee respectively. In the Canephora species were evaluated eigth genotypes of conilon and robusta which did not show significant difference among them related to yield, although it was observed a difference of 7 sacks/ha more for the gentotypes IAC 66-3 when compared to the local Conilon. In this group it was noted drought stress during the dry season (July/August) for all the genotypes.

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