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1.
Braz J Biol ; 83: e276127, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422265

RESUMO

The study aimed to evaluate the insecticidal activity of extracts of edible mushrooms Pleurotus ostreatus and Lentinula edodes against Rhyssomatus nigerrimus. Methanol:water extracts (70:30) of P. ostreatus and L. edodes were made and evaluated in two in vitro tests (exposure and immersion toxic effect) against R. nigerrimus. Subsequently, the toxicity test of the extracts against Artemia salina was evaluated. These extracts were subjected to colorimetric tests and gas chromatography-mass spectrometry. The results showed a mortality effect against R. nigerrimus of 50% for the P. ostreatus 2 extracts at a concentration of 20% in the immersion test. Likewise, in the toxic effect test, 90% mortality was observed after five days of exposure to a concentration of 10%. On the other hand, for the toxicity test, the extract that showed the values with the highest mortality against A. salina was P. ostreatus, starting with 80% mortality at 100µg/mL. The functional groups present in the extracts were saponins, coumarins, and alkaloids. Furthermore, the presence of more than 7 compounds in the mushroom extracts evaluated is reported. This study demonstrates the insecticidal activity of P. ostreatus and L. edodes fungal extracts and indicates the importance of using different in vitro tests to elucidate the mechanism of action for future studies.


Assuntos
Artrópodes , Inseticidas , Pleurotus , Cogumelos Shiitake , Gorgulhos , Animais , Metanol , Artemia
2.
J Helminthol ; 96: e13, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35195061

RESUMO

In the present study, the nematicidal activity of a Moringa oleifera ethyl acetate leaf extract against the eggs and larvae of Haemonchus contortus and Nacobbus aberrans, nematodes of agricultural importance, was evaluated. The experimental design for the evaluation of the effects against both nematodes consisted of eight treatments (n = 4). Distilled water, Tween (4%) and a commercial anthelmintic agent (ivermectin, 5 mg/mL) were used as controls, and for treatments 4-8, the concentrations of the extract were 20, 10, 5, 2.5 and 1.25 mg/mL, respectively. Readings were taken at 12 h and 24 h for N. aberrans and 48 h and 72 h for H. contortus post-treatment under an optical microscope (10× and 40×). The data obtained were analysed by analysis of variance through a completely randomized factorial design using the SAS V9 program. The results show that, for H. contortus egg hatching, 85.88% inhibition was obtained at a concentration of 20 mg/mL at 48 h, while for third-stage larva (L3) mortality, the highest percentage was 68.19% at 1.25 mg/mL at 72 h. In the case of N. aberrans, the greatest inhibition of egg hatching was 90.69% at 5 mg/mL at 12 h post-treatment, and for larval mortality, it was 100% at 10 mg/mL at 24 h post-treatment. The main major compounds identified by qualitative analysis and by gas chromatography coupled to mass spectrometry were 9,12,15-octadecatrienoic acid, (Z,Z,Z)-, n-hexadecanoic acid and 2,4-di-tert-butylphenol, and the minor compounds included phytol, γ-sitosterol and α-tocopheryl acetate. It was demonstrated that the ethyl acetate leaf extract of M. oleifera Lam. shows great potential for combating agricultural nematodes.


Assuntos
Anti-Helmínticos , Haemonchus , Moringa oleifera , Animais , Anti-Helmínticos/farmacologia , Antinematódeos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Larva , Extratos Vegetais/química , Extratos Vegetais/farmacologia
3.
J Appl Microbiol ; 127(2): 495-507, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31077511

RESUMO

AIMS: The aim of this study was to investigate the dynamic changes in the bacterial structure and potential interactions of an acclimatized marine microbial community during a light crude oil degradation experiment. METHODS AND RESULTS: The bacterial community effectively removed 76·49% of total petroleum hydrocarbons after 30 days, as evidenced by GC-FID and GC-MS analyses. Short-chain alkanes and specific aromatic compounds were completely degraded within the first 6 days. High-throughput sequencing of 16S rRNA gene indicated that the starting bacterial community was mainly composed by Marinobacter and more than 30 non-dominant genera. Bacterial succession was dependent on the hydrocarbon uptake with Alcanivorax becoming dominant during the highest degradation period. Sparse correlations for compositional data algorithm revealed one operational taxonomic unit (OTU) of Muricauda and an assembly of six OTUs of Alcanivorax dieselolei and Alcanivorax hongdengensis as critical keystone components for the consortium network maintenance and stability. CONCLUSIONS: This work exhibits a stabilized marine bacterial consortium with the capability to efficiently degrade light crude oil in 6 days, under laboratory conditions. Successional and interaction patterns were observed in response to hydrocarbon consumption, highlighting potential interactions between Alcanivorax and keystone non-dominant OTUs over time. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results contribute to the understanding of interactions and potential roles of specific members of hydrocarbonoclastic marine bacterial communities, which will be useful for further bioaugmentation studies concerning the associations between indigenous and introduced micro-organisms.


Assuntos
Bactérias/metabolismo , Consórcios Microbianos , Petróleo/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Golfo do México , RNA Ribossômico 16S/genética
4.
Bull Environ Contam Toxicol ; 101(2): 160-165, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29721597

RESUMO

We examined the sediments of four coastal lagoons (Ria Lagartos, Bocas de Dzilam, Laguna de Chelem and Ria Celestun) from the state of Yucatan, Mexico, for three widely used commercial polybrominated diphenyl ethers formulations (penta-, octa- and deca-BDE). The most commonly found congeners in all four lagoons were BDEs 47, 99 and 100 (all in the penta-BDE formulation) and BDE209 (deca-BDE formulation). The greatest variety and highest concentrations of brominated flame retardants were found in Ria Lagartos, which also showed the highest BDE 100 concentration (24.129 ng/g). Hexabromocyclododecane was found in all lagoons, but at lower concentrations than those of the various polybrominated diphenyl ethers. Dispersal routes of these compounds are discussed, such as a ring of sinkholes (cenotes) adjacent to the lagoons. Moreover, electronic waste is a serious problem because municipal landfills have been the primary disposal method for these wastes and therefore represent a reservoir of brominated fire retardants.


Assuntos
Retardadores de Chama/análise , Sedimentos Geológicos/análise , Éteres Difenil Halogenados/análise , Hidrocarbonetos Bromados/análise , Monitoramento Ambiental , Estuários , México
5.
Med. interna Méx ; 33(4): 443-451, jul.-ago. 2017. graf
Artigo em Espanhol | LILACS | ID: biblio-894283

RESUMO

Resumen: OBJETIVO: determinar la frecuencia del síndrome metabólico en una cohorte de pacientes con lupus eritematoso sistémico y su relación con la actividad de la enfermedad y los factores de riesgo cardiovascular. MATERIAL Y MÉTODO: estudio descriptivo, transversal y observacional en el que de junio de 2015 a junio de 206 se incluyeron pacientes con diagnóstico de lupus eritematoso sistémico según los criterios SLICC 2012, la actividad de la enfermedad se evaluó mediante el índice SLEDAI 2K. Se estableció la existencia de síndrome metabólico de acuerdo con los criterios NECP ATP III. Las variables categóricas se compararon con χ2 y las continuas con U de Mann-Whitney o t de Student. Finalmente se utilizó un modelo de regresión logística multivariante para determinar la asociación de las variables estudiadas y el síndrome metabólico. RESULTADOS: se incluyeron 102 pacientes de los que 41% tenía síndrome metabólico (60% de los hombres y 39% de las mujeres). Las principales alteraciones fueron hipoalfalipoproteinemia (75.5%), perímetro abdominal aumentado (63%) e hipertrigliceridemia (60%). Se observó que a mayor número de componentes del síndrome metabólico existía mayor actividad de la enfermedad. Un índice SLEDAI 2K ≥ 4 se asoció independientemente con síndrome metabólico (RR 2.89; IC 1.21-6.89; p=0.017). La administración de hidroxicloroquina se asoció de manera independiente con la ausencia de síndrome metabólico (RR 0.48; IC 0.19-0.39; p=0.14). Se encontró significación entre la actividad de la enfermedad y la hipoalfalipoproteinemia (p=0.007) y la hipertrigliceridemia (p=0.035). CONCLUSIONES: existe frecuencia alta de síndrome metabólico en las pacientes con lupus eritematoso sistémico, la cual se asocia con la actividad de la enfermedad.


Abstract: OBJECTIVE: To determine the frequency of metabolic syndrome in a cohort of patients with systemic lupus erythematous and its relationship with disease activity and cardiovascular risks factors. MATERIAL AND METHOD: A descriptive, cross-sectional and observational study including patients diagnosed with systemic lupus erythematous according to the SLICC 2012 criteria, disease activity was evaluated through SLEDAI 2K from June 2015 to June 2016. The presence of metabolic syndrome was established according to the NECP ATP III criteria. Categorical variables were compared with χ2 and the continuous ones with Mann-Withney U or Student t. Finally, a logistic regression multivariate model was used to determine the association of the studied variables and the metabolic syndrome. RESULTS: One hundred two patients were included; from which 41 % of the patients presented with metabolic syndrome (60% of men and 39% of women). The main alterations were hypoalphalipoproteinemia (75.5%), elevated abdominal circumference (63%) and hypertriglyceridemia (60%). It was observed that with a higher number of components of the metabolic syndrome a major disease activity existed. An SLEDAI 2K index ≥ 4 was associated independently with the presence of metabolic syndrome (RR 2.89; IC 1.21-6.89; p=0.017). Hydroxicloroquine use was associated in an independent manner with the absence of the metabolic syndrome (RR 0.48; IC 0.19-0.39; p=0.14). Statistic significance was found between disease activity and hypoalphalipoproteinemia (p=0.007) and hypertriglyceridemia (p=0.035). CONCLUSION: There is a high frequency of metabolic syndrome in patients with systemic lupus erythematous, which is associated with disease activity.

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