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1.
Insects ; 12(10)2021 Oct 06.
Article in English | MEDLINE | ID: mdl-34680680

ABSTRACT

The broad mite (BM) Polyphagotarsonemus latus is a pest of great prominence for several crops, including the common bean (Phaseolus vulgaris). The objective of this study was to select resistant genotypes and to determine chemicals associated with resistance. In the first experiment, BM incidence was assessed for 36 genotypes in a greenhouse study. A group of 10 genotypes was selected according to the development of BM populations. Mite populations and phytometric and biochemical variables were then determined to study eventual differential genotypic responses to mite infestation. Lower numbers of mite mobile forms (larvae + adults) were found on Verdão, Negrão and Carioca Original genotypes. The magnitude of differences reached 5.4 times more BM in the IAC Alvorada than the Verdão genotype. Plant yields were reduced for the genotypes TAA Bola Cheia, IPR Sabiá, IPR Uirapuru, IAC Alvorada and Carioca Original when plants were infested with BM. The yields for LP 13833, BRS Esteio, Negrão 11, Verdão and MD 1133 were similar between infested and non-infested genotypes, indicating tolerance. Verdão and Negrão 11, besides the tolerance, exhibited low offspring development, indicating antibiosis and/or antixenosis. Higher phenolic compound levels were found in the Verdão genotype. Increased contents of catalase and peroxidase were detected for Negrão 11 genotype when infested with BM. This work allowed the detection of common bean genotypes that express resistance and tolerance to BM. These genotypes can be used in places with a history of BM infestation, or used in breeding programs to incorporate these characteristics in other genotypes.

2.
Bol. latinoam. Caribe plantas med. aromát ; 19(5): 495-507, 2020. tab, graf
Article in English | MOSAICO - Integrative health, LILACS | ID: biblio-1145991

ABSTRACT

La composición química del aceite esencial obtenido de las ramas de Ocotea paranaensis se estudió por cromatografía de gases/espectrometría de masas (CG/MS). Se identificaron veintisiete compuestos, que comprenden el 94,82% de los componentes totales. El aceite se caracterizó por una concentración relativamente alta de sesquiterpenos (62,96%), sesquiterpenos oxigenados (33,33%) y diterpeno (3,70%). En cuanto a los compuestos principales, se destacaron Z-nerolidol (19,16%), germacreno D (12,92%) y α-bulnesene (8,47%), que correspondieron al 40,55% de las sustancias encontradas. El aceite esencial analizado de Ocotea paranaensis tiene una buena acción reductora de fosfomolibdeno y es moderadamente tóxico para la Artemia salina (LC50 = 147,91 µg/mL). Mostró potencial hemolítico y actividad moderada contra Staphylococcus aureus (concentración inhibitoria mínima MIC = 250 µg/mL) y Pseudomonas aeruginosa (MIC = 500 µg/mL). No se observaron resultados satisfactorios de citotoxicidad en el linaje H460 y HeLa.


The chemical composition of the essential oil obtained from the branches of Ocotea paranaensis was studied by gas chromatography/mass spectrometry (GC/MS). Twenty-seven compounds, comprising 94.82% of the total components, were identified. The oil showed relatively high concentration of sesquiterpenes (62.96%), oxygenated sesquiterpenes (33.33%), and diterpene (3.70%). Regarding the major compounds, Z-nerolidol (19.16%), germacrene D (12.92%) and α-bulnesene (8.47%) could be highlighted, which corresponded to 40.55% of the substances that were found. The essential oil from Ocotea paranaensis has phosphomolybdenum reducing action and is moderately toxic to the Artemia salina (LC50 = 147.91 µg/mL). It showed haemolytic potential and moderate activity against Staphylococcus aureus, (minimum inhibitory concentration MIC = 250 µg/mL) and Pseudomonas aeruginosa (MIC = 500 µg/mL). No satisfactory cytotoxicity results were observed in lineage H460 and HeLa.


Subject(s)
Ocotea/chemistry , Anti-Infective Agents , Antineoplastic Agents , Antioxidants , Plant Extracts , Chromatography , Medicine, Traditional
3.
Braz. J. Pharm. Sci. (Online) ; 55: e18471, 2019. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1055309

ABSTRACT

The article has aimed to characterize the essential oil extracted from Ocotea diospyrifolia (Meisn.) Mez. leaves, in terms of its chemical composition and antioxidant, hemolytic, and phytotoxic potentials, as well as its toxicity against Artemia salina. The major constituents identified by CG-MS were d-elemene, spathulenol, and b-atlantol. When screened for potential biological activities, the essential oil presented low toxicity against Artemia salina, and a capacity of lysing red blood cells. Also, the evaluation of its in vitro antioxidant activity, using the phosphomolybdenum method, showed better results when compared to butylhydroxytoluene (BHT) and rutin. In conclusion, the results obtained showed certain in vitro toxicity, leading to an interesting target for cytotoxicity evaluations of carcinoma cells.

4.
Braz. j. pharm. sci ; 49(3): 537-547, July-Sept. 2013. ilus
Article in English | LILACS | ID: lil-689907

ABSTRACT

Stigmasterol - a plant sterol with several pharmacological activities - is susceptible to oxidation when exposed to air, a process enhanced by heat and humidity. In this context, microencapsulation is a way of preventing oxidation, allowing stigmasterol to be incorporated into various pharmaceutical forms while increasing its absorption. Microparticles were obtained using a blend of polymers of sodium alginate, starch and chitosan as the coating material through a one-stage process using the external gelation technique. Resultant microparticles were spherical, averaging 1.4 mm in size. Encapsulation efficiency was 90.42% and method yield 94.87%. The amount of stigmasterol in the oil recovered from microparticles was 9.97 mg/g. This technique proved feasible for the microencapsulation of stigmasterol.


O estigmasterol, um fitoesterol com diversas atividades farmacológicas, é suscetível à oxidação quando exposto ao ar, calor e umidade. Neste contexto, a microencapsulação é uma forma de proteção contra oxidação, permitindo a incorporação do estigmasterol em diversas formas farmacêuticas e aumentar sua absorção. As micropartículas foram obtidas por gelificação iônica externa, em uma etapa, utilizando como revestimento polímeros naturais de alginato de sódio, amido de milho e quitosana. As micropartículas apresentaram formato esférico com tamanho aproximado de 1,4 mm. O rendimento foi de 94,87% e a eficiência média de encapsulação de 90,42%. A quantidade de estigmasterol no óleo recuperado das micropartículas foi de 9,97 mg/g. O método mostrou-se viável para a microencapsulação do estigmasterol.


Subject(s)
Stigmasterol/analysis , Alginates/classification , Gelling Agents , Starch , Chitosan , Drug Compounding/classification , /classification
5.
Braz. arch. biol. technol ; 52(6): 1333-1340, Nov.-Dec. 2009. ilus, tab
Article in English | LILACS | ID: lil-539099

ABSTRACT

Several synthetic and commercial analogs of 1,4-dimethoxybenzene, a kairomone of Diabrotica speciosa, along with other compounds already shown to be attractive to other species of Diabrotica, were tested as attractant to D. speciosa. Yellow cup traps were lured with the compounds and installed in a common bean field. Assessments were conducted 24 h later. 1,4-dimethoxybenzene lured traps caught significantly more beetles than the control traps. Captures of traps lured with 1,4-dimethoxybenzene analogs did not differ from the control traps. Results showed that position and nature of the substituents on the aromatic ring played a crucial role in the activity of the natural compound. The aromatic ring was also very important to the activity of the kairomone.


Uma série de compostos, sintéticos e comerciais, análogos ao 1,4-dimetoxibenzeno, um cairomônio de Diabrotica speciosa, juntamente com outros compostos comerciais atrativos para outras espécies de Diabrotica, tiveram suas atividades testadas frente à D. speciosa. Armadilhas de copos amarelos contendo os compostos foram instaladas em plantação de feijão. As avaliações foram realizadas 24 horas depois. Armadilhas com 1,4-dimetoxibenzeno capturaram significativamente mais insetos do que armadilhas testemunha. Armadilhas com análogos do 1,4-dimetoxibenzeno não capturaram mais insetos que as armadilhas testemunha. Os resultados mostraram que a posição e a natureza dos substituintes, juntamente com a aromaticidade verificada na estrutura do composto natural, são cruciais para a atratividade.

6.
Behav Processes ; 82(3): 236-43, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19591909

ABSTRACT

Signals of different modalities are involved during courtship of the brown spider Loxosceles intermedia. A spine on the pedipalp is rubbed against the grooves on the retrolateral region of the chelicerae producing stridulatory signals, which have a dominant frequency of the airborne component range around 770 Hz for females and around 170 Hz for males. These values are significantly lower for the substrate-borne component. The sound pressure level of stridulatory signals lies below 50 dB and the velocity values below 1mm/s. The copulation frequency does not depend on the presence of pedipalps in females; however, in males the removal of pedipalps decreases the courtship frequency. During courtship, females vibrate their abdomens after being touched by the courting male, producing tremulatory signals with the dominant frequency below 100 Hz, sound pressure level below 60 dB and velocity below 3mm/s. This vibration may function as a sign of the akinesia state since it precedes the introduction of the embolus. Cuticular compounds probably determine the recognition of the male by the female. Data from the present study corroborate the generalist nature of L. intermedia in which signals of different modalities are used during courtship.


Subject(s)
Animal Communication , Copulation/physiology , Courtship , Pheromones/physiology , Spiders/physiology , Analysis of Variance , Animals , Chi-Square Distribution , Female , Male , Microscopy, Electron, Scanning , Motor Activity/physiology , Sound , Spiders/anatomy & histology , Vibration
7.
J. bras. ginecol ; 95(5): 165-8, maio 1985. tab
Article in Portuguese | LILACS | ID: lil-6224

ABSTRACT

Estudamos 65 pacientes primigestas matriculadas no ambulatório pré-natal da Maternidade-Escola da Universidade Federal do Rio de Janeiro. Para seleçäo da populaçäo era condiçäo fundamental a primigestaçäo e o conhecimento preciso do último catamênio. Após rigorosa história clínica e apurado exame físico eram excluídas as portadoras de qualquer patologia clínica ou obstétrica. Realizamos dois testes da hipertensäo supina em épocas diferentes. O primeiro teste feito entre a 22§ e 24§ semanas de gravidez e o segundo entre a 28§ e 32§ semanas. Concluímos que o segundo teste tem maior poder preditivo do que o primeiro sendo que a associaçäo dos dois testes melhora a especificidade e piora a sensibilidade. O segundo teste apresentou sensibilidade de 77,27% e especificidade de 82,14%, mostrando que deve ser mais valorizado quando negativo do que quando positivo


Subject(s)
Pregnancy , Humans , Female , Hypertension/diagnosis , Pre-Eclampsia/diagnosis , Pregnancy Trimester, Second , Pregnancy Trimester, Third , Prenatal Care
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