RESUMEN
The continuous use of synthetic anthelmintics against gastrointestinal nematodes (GINs) has resulted in the increased resistance, which is why alternative methods are being sought, such as the use of natural products. Plant essential oils (EOs) have been considered as potential products for the control of GINs. However, the chemical composition and, consequently, the biological activity of EOs vary in different plant cultivars. The aim of this study was to evaluate the anthelmintic activity of EOs from cultivars of Ocimum basilicum L. and that of their major constituents against Haemonchus contortus. The EOs from 16 cultivars as well the pure compound linalool, methyl chavicol, citral and eugenol were used in the assessment of the inhibition of H. contortus egg hatch. In addition, the composition of three cultivars was simulated using a combination of the two major compounds from each. The EOs from different cultivars showed mean Inhibition Concentration (IC50) varying from 0.56 to 2.22 mg/mL. The cultivar with the highest egg-hatch inhibition, Napoletano, is constituted mainly of linalool and methyl chavicol. Among the individual compounds tested, citral was the most effective (IC50 0.30 mg/mL). The best combination of compounds was obtained with 11% eugenol plus 64% linalool (IC50 0.44 mg/mL), simulating the Italian Large Leaf (Richters) cultivar. We conclude that different cultivars of O. basilicum show different anthelmintic potential, with cultivars containing linalool and methyl chavicol being the most promising; and that citral or methyl chavicol isolated should also be considered for the development of new anthelmintic formulations.
Asunto(s)
Antihelmínticos , Haemonchus , Ocimum basilicum , Aceites Volátiles , Extractos Vegetales , Animales , Antihelmínticos/farmacología , Haemonchus/efectos de los fármacos , Ocimum basilicum/química , Aceites Volátiles/farmacología , Óvulo/efectos de los fármacos , Extractos Vegetales/farmacologíaRESUMEN
The effects of unfavorable conditions responsible for the viability loss of Lactococcus cells during spray drying can be minimized by the application of dairy matrices as encapsulating materials. This study aimed to evaluate the use of dairy matrices with different lactose contents on the survival of Lactococcus lactis during drying and storage. The use of hydrolyzed-lactose milk resulted in notable loss of cell viability (3.90 log cycles). However, milk enriched with lactose or without fat showed better protection (viability loss between 0.26 and 1.41 log cfu/g) and greater cell survival during storage at room temperature. The enrichment of milk with lactose seems to be ideal for the drying of heat-sensitive bacteria.
Asunto(s)
Desecación/métodos , Lactococcus lactis/metabolismo , Lactosa/metabolismo , Leche/metabolismo , Análisis de Varianza , Animales , Calor , Hidrólisis , Leche/químicaRESUMEN
Spray drying presents a promising technology for preserving bacteria despite a low survival rate of heat-sensitive cultures when subjected to the drying process. The aim of this study was to determine the ideal powder parameters [water activity (Aw) and temperature (T°Cpowder)] needed to produce dehydrated Lactococcus lactis ssp. lactis with a high viability after drying. Cell concentrates injected into a spray dryer using varying cell concentrate flow rates (Fconcentrate = 0.3 to 1.0 kg/h), inlet air temperatures (T°Cinlet air = 115 to 160°C), and outlet air temperatures (T°Coutlet air = 70 to 115°C) resulted in powders with different values of Aw and T°Cpowder, and levels of cell viability loss. Lower cell viability reduction (â¼0.43 log cycles) was obtained in conditions of Aw = 0.198 and T°Cpowder = 52°C, which can be met by using T°Cinlet air â¼126°C and T°Coutlet air = 88.9°C regardless of Fconcentrate values. After 60 d of storage at room temperature, cell population varied from 7.0 × 105 to 1.1 × 108 cfu/g. The initial powder Aw had no influence on cell death rate, but T°Cpowder influence was observed. The approach adopted in this study can be applied to other bacteria or spray dryer equipment to determine optimal drying conditions.
Asunto(s)
Técnicas Bacteriológicas/métodos , Desecación , Lactococcus lactis/fisiología , Agua/análisis , Polvos/análisis , TemperaturaRESUMEN
AIMS: The study investigated whether the interaction with Lactobacillus rhamnosus (ATCC7469) interfere with the expression of virulence factors by Candida albicans (ATCC18804). METHODS AND RESULTS: These micro-organisms were grown in biofilms for 24, 48 and 72 h, Candida was isolated and the expression of the major virulence factors were investigated. The production of phospholipase, protease and haemolysin were observed in appropriate media; observation of germ tubes formation in serum; biofilm formation, after growth in microtitre plates and reading in spectrophotometer. Candida was also tested for antifungal sensitivity to amphotericin B, fluconazole and ketoconazole. The results were compared with the cells of Candida grown in the absence of lactobacilli (control group). Candida cells, which interacted with Lact. rhamnosus (test group), showed significantly lower proteinase and haemolysin activity, when compared with control group. The germ tube formation and biofilm formation capacity also decreased in tested groups, which demonstrated alterations in susceptibility to antifungal drugs. CONCLUSIONS: The results suggest that Lact. rhamnosus is able to influence the expression of virulence factors by C. albicans and can alter its antifungal sensitivity profile. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest reduction in the pathogenicity of Candida and improvement in candidiasis therapy and control.
Asunto(s)
Candida albicans/efectos de los fármacos , Candida albicans/patogenicidad , Lacticaseibacillus rhamnosus/fisiología , Antifúngicos/farmacología , Biopelículas/crecimiento & desarrollo , Candida albicans/aislamiento & purificación , Candida albicans/fisiología , Interacciones Microbianas , Factores de Virulencia/metabolismoRESUMEN
Several species within the genus Theobroma have particularly high economic value, including T. cacao and T. grandiflorum. Other species in this genus, such as T. speciosum and T. subincanum, have potential value for use in the conservation of genetic diversity in breeding programs. These latter species could also be domesticated or improved to produce commercial products. Using 13 simple sequence repeat loci, the population structure and genetic diversity of T. speciosum and T. subincanum natural populations in the Juruena National Park, Mato Grosso State, Brazil, was studied. We sampled all individuals of each species (N = 25) present inside a designated research area established by the Program for Research on Biodiversity. The average number of alleles per locus was 5 for T. speciosum and 6.69 for T. subincanum, with average PIC values above 0.5 in both species. All evaluated individuals varied genetically. Seeds from the individuals analyzed will be useful for the development of germplasm banks and for establishment of breeding programs.
Asunto(s)
Genética de Población , Malvaceae/genética , Parques Recreativos , Alelos , Brasil , Frecuencia de los Genes/genética , Variación Genética , Geografía , Heterocigoto , FilogeniaRESUMEN
Cassia angustifolia Vahl. (senna) is commonly used in self-medication and is frequently used to treat intestine constipation. A previous study involving bacteria and plasmid DNA suggested the possible toxicity of the aqueous extract of senna (SAE). The aim of this study was to extend the knowledge concerning SAE genotoxicity mechanisms because of its widespread use and its risks to human health. We investigated the impact of SAE on nuclear DNA and on the stability of mitochondrial DNA in Saccharomyces cerevisiae (wt, ogg1, msh6, and ogg1msh6) strains, monitoring the formation of petite mutants. Our results demonstrated that SAE specifically increased Can(R) mutagenesis only in the msh6 mutant, supporting the view that SAE can induce misincorporation errors in DNA. We observed a significant increase in the frequency of petite colonies in all studied strains. Our data indicate that SAE has genotoxic activity towards both mitochondrial and nuclear DNA.
Asunto(s)
Núcleo Celular/genética , Genoma Mitocondrial/efectos de los fármacos , Inestabilidad Genómica/efectos de los fármacos , Extractos Vegetales/farmacología , Saccharomyces cerevisiae/genética , Senna/química , Agua/química , Saccharomyces cerevisiae/efectos de los fármacosRESUMEN
Yacon is a highly perishable tuberous root, rich in fructooligosaccharides (FOS). Convective drying preceded by ethanol treatment (ET) is an alternative for increasing shelf life in a shorter process. The aim of this study was to investigate the impact of ET and temperature (50 °C and 70 °C) on quality parameters (fructan retention, total phenolic content, antioxidant capacity, shrinkage, color and microstructural parameters) and process parameters (drying time, drying kinetics, and energy consumption) in the convective drying of yacon slices. The ET induced structural alterations in the tissues and cells that aids in the reduction of drying time up to 28.00 %. ET resulted in an increase in effective diffusivity and leaded to noteworthy reduction in energy consumption (up to 22.72 %). The quality parameters such as color, shrinkage, and total phenolic content showed no significant differences among the treatments. The use of ethanol promoted highest preservation of antioxidant activity; however, it caused degradation of FOS. The ethanol pretreated drying at 50 °C was the better condition for lower consumption and preservation of quality parameters as total phenolic content, antioxidant capacity and fructan retention, but the samples dried at 50 °C were the ones with the highest fructan retention (55.11 ± 2.19 %).
Asunto(s)
Antioxidantes , Etanol , Antioxidantes/química , Fenoles/química , Desecación/métodos , FructanosRESUMEN
Duguetia furfuracea (St. Hil.) Benth & Hook f. (1862), popularly known as "sofre-do-rim-quem-quer" and "araticum-seco", is a shrub of the Annonaceae family that grows in several regions of Brazil. Infusions of its leaves and twigs are used in folk medicine to treat rheumatism and renal colic, whereas the seed powder is mixed with water to treat pediculosis. Studies on the plant have reported biological activities with cytotoxic, antitumoral, trypanocidal, leishmanicidal, antiplasmodial, and antiprotozoal effects. Our previous studies using a prophage λ induction test (SOS-Inductest) and the micronucleus assay demonstrated that D. furfuracea lyophilized leaf extract (DFE) displayed cytotoxic but not genotoxic activity. In the present study, antigenotoxic and anticytotoxic activities of DFE were evaluated using SOS-Inductest and mouse bone marrow micronucleus tests. Our results showed that DFE decreased the induction of either prophage λ (P < 0.05; SOS-Inductest) or micronucleated polychromatic erythrocytes (P < 0.05; micronucleus test) at all doses, suggesting antigenotoxic activity in both tests. On assessing the anticytotoxic activity of DFE, a significant increase in the number of bacteria at lower doses (P < 0.05) as well as a significant increase in the polychromatic and normochromatic erythrocyte ratio were observed (P < 0.05), demonstrating the anticytotoxic activity of DFE. Thus, D. furfuracea displayed antigenotoxic and anticytotoxic activity in both assays.
Asunto(s)
Annonaceae/química , Antimutagênicos/farmacología , Bacterias/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Citotoxinas/farmacología , Daño del ADN/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Masculino , Ratones , Pruebas de Micronúcleos , Hojas de la Planta/químicaRESUMEN
Salacia crassifolia (Mart. Ex. Schult.) G. Don., popularly known in Brazil as "bacupari", "cascudo", and "saputá", is a shrub of the Celastraceae family that is unique to the Brazilian Cerrado region. In folk medicine, this plant has been mainly used to treat skin cancer and gastric ulcers. In the present study, the genotoxic, cytotoxic, antigenotoxic, and anticytotoxic effects of S. crassifolia stem bark fractions (hexane, ethyl acetate, and hydroalcoholic extracts) were evaluated using the mouse bone marrow micronucleus test. Our results showed that none of the S. crassifolia fractions led to a significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCE) (P > 0.05), suggesting the absence of genotoxicity. In the antigenotoxicity assessment, a significant decrease in the MNPCE frequency was observed in all fractions of this plant (P < 0.05), demonstrating its protective action against genotoxicity induced by mitomycin C (MMC), which was used as the positive control. Only the hexane fraction of S. crassifolia significantly decreased the poly- and normochromatic erythrocyte ratio (PCE/NCE) in all doses tested (P < 0.05), demonstrating its cytotoxic activity. In association with MMC, both ethyl acetate and hydroalcoholic fractions significantly increased the PCE/NCE ratio in almost all doses tested (P < 0.05), demonstrating the protective action of S. crassifolia against the cytotoxic effect of the positive control. In contrast, the hexane fraction presented a significant decrease in the PCE/NCE ratio in all treatments (P < 0.05), demonstrating an increase in this plant's cytotoxicity in mouse bone marrow cells.
Asunto(s)
Citotoxinas/farmacología , Daño del ADN , Corteza de la Planta/química , Extractos Vegetales/farmacología , Salacia/química , Animales , Antibióticos Antineoplásicos/farmacología , Células de la Médula Ósea/efectos de los fármacos , Fraccionamiento Químico , Citotoxinas/química , Citotoxinas/toxicidad , Eritrocitos/efectos de los fármacos , Ratones , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Mitomicina/farmacología , Extractos Vegetales/química , Extractos Vegetales/toxicidad , Tallos de la Planta/química , Salacia/anatomía & histologíaRESUMEN
Hymenaea courbaril L., popularly known as jatobá, is a plant species that grows in the forests of South America. The species has been used for culinary purposes and in folk medicine to treat arthritis and inflammations. Due to the increasing use of this plant globally, the present study aimed to evaluate the toxic, genotoxic, recombinogenic, and antigenotoxic effects of H. courbaril sap (Hycs) using the mouse bone marrow micronucleus test and the somatic mutation and recombination test (SMART) in Drosophila melanogaster. To evaluate the aneugenic and clastogenic activities revealed by the micronucleus test, the animals were treated with 3 doses of Hycs (5, 10, and 15 mL/kg body weight). To evaluate the antianeugenic and anticlastogenic activities, the animals were simultaneously treated with Hycs and mitomycin C (4 mg/kg body weight). To assess the mutagenic and recombinogenic activities using SMART, 3-day-old larvae derived from standard and high bioactivation crosses were treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) for approximately 48 h. To evaluate antimutagenic and antirecombinogenic activities, larvae derived from both crosses were co-treated with 3 doses of Hycs (3.0, 1.5, and 0.3 mL) and doxorubicin (0.125 mg/ mL). The mouse bone marrow micronucleus test revealed that Hycs exhibited no cytotoxic, clastogenic and/or aneugenic effects, but did show anticytotoxic, anticlastogenic and/or antianeugenic activities. The SMART revealed no mutagenic or recombinogenic effects, but antimutagenic and antirecombinogenic activities were observed in somatic cells of D. melanogaster from both crosses.
Asunto(s)
Daño del ADN , Hymenaea/química , Mutagénesis/efectos de los fármacos , Extractos Vegetales/toxicidad , Recombinación Genética/efectos de los fármacos , Animales , Células de la Médula Ósea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Drosophila melanogaster , Larva/efectos de los fármacos , Ratones , Micronúcleos con Defecto Cromosómico/inducido químicamente , Extractos Vegetales/farmacologíaRESUMEN
Lafoensia pacari (Lythraceae), popularly known in Brazil as "pacari", is a small tree native to the Cerrado that is used in folk medicine to treat cancer and as an anti-inflammatory and cicatrizing agent. We evaluated the genotoxic, cytotoxic, antigenotoxic, and anticytotoxic activities of an ethanol extract of L. pacari stem bark (EESB) using the Ames test and the mouse bone marrow micronucleus test. In the Ames test, EESB did not significantly increase the number of His(+) revertants in Salmonella typhimurium tester strains TA98 and TA100 at all doses, demonstrating lack of mutagenicity. Only the highest dose of EESB significantly increased the micronucleated polychromatic erythrocyte frequency in the micronucleus test, indicating mild genotoxicity. EESB produced a mutagenic index lower than the negative control in the Ames test. In the micronucleus test, at all doses, EESB caused a significant decrease in the polychromatic/normochromatic erythrocyte ratio (PCE/NCE) at 24 h compared with the negative control. EESB co-administered together with the respective positive control caused a significant decrease in the number of His(+) revertant colonies in the Ames test and in the frequency of micronucleated polychromatic erythrocytes in the micronucleus test, demonstrating a DNA protector effect. EESB co-administered with mitomycin C significantly increased the PCE/NCE ratio at all doses, showing an anticytotoxic effect. We conclude that EESB has antigenotoxic and anticytotoxic properties.
Asunto(s)
Antimutagênicos/farmacología , Daño del ADN/efectos de los fármacos , Lythraceae/química , Corteza de la Planta/química , Extractos Vegetales/farmacología , Animales , Relación Dosis-Respuesta a Droga , Eritrocitos/química , Etanol/metabolismo , Masculino , Ratones , Pruebas de Micronúcleos , Mitomicina/farmacología , Mutágenos/análisis , Salmonella typhimurium/efectos de los fármacosRESUMEN
A subtractive cDNA library from cotton buds was constructed to prospect for differentially expressed genes related to early bud development. A library was constructed and 768 cDNA sequences were obtained, comprising 168 clusters, with 126 contigs and 42 singlets. Both the Gossypium as well as Arabidopsis databases were utilized for the in silico analysis, since some genes identified in cotton have not yet been studied for functionality, although they have homology with genes from other species. The transcriptome revealed a large number of transcripts, some of them with unknown function, and others related to pollen development, pollen tubes, ovules, and fibers at different stages. The most populated contig was identified as fiber from 0-10 days after anthesis, with 12 reads. The success and novelty rates generated from the library were 67 and 51%, respectively. The information obtained here will provide a framework for research on functional cotton genomics.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Gossypium/crecimiento & desarrollo , Gossypium/genética , Fibra de Algodón , ADN Complementario/genética , Biblioteca de Genes , Transcriptoma/genéticaRESUMEN
Salinity is harmful to crops when the concentration of soluble salts overcomes the salinity threshold of the crop, causing osmotic stress and limitations in plant growth. In this scenario, adopting tolerant cultivars is the most adequate strategy to minimize agricultural losses. However, the inheritance of tolerance depends on the genotype. From this perspective, this study assessed the tolerance to severe salt stress in 11 cotton cultivars based on gas exchange parameters and the free proline content. The cultivars were grown in a greenhouse and subjected to 34 days of saline irrigation (10 dS m-1), starting 45 days after seedling emergence (B1 phase). Plant growth was monitored weekly until the end of the salt stress period. The treatments consisted of a combination of two factors: eleven cultivars associated with two electrical conductivity levels of irrigation water (ECw: 0.3 and 10.0 dS m-1). The experimental design was in randomized blocks in a 11 × 2 factorial arrangement with three replications (66 plots), with the experimental unit consisting of one plant per plot. Salinity impacted plant growth, being reflected on the gas exchange and free proline data of most cultivars. However, BRS 286, FMT 705, BRS 416, and BRS Acácia, and CNPA 7MH withstood the effects of stress and osmotically adjusted to the salt stress conditions, thus minimizing the damage to growth. Those cultivars are the most indicated for improvement programs aiming at tolerance to salt stress based on the results found in this research.
Asunto(s)
Estrés Salino , Tolerancia a la Sal , Plantones , Salinidad , ProlinaRESUMEN
The thermoelastic properties of ferropericlase Mg(1-x)Fe(x)O (x = 0.1875) throughout the iron high-to-low spin cross-over have been investigated by first principles at Earth's lower mantle conditions. This cross-over has important consequences for elasticity such as an anomalous bulk modulus (K(S)) reduction. At room temperature the anomaly is somewhat sharp in pressure but broadens with increasing temperature. Along a typical geotherm it occurs across most of the lower mantle with a more significant K(S) reduction at approximately 1,400-1,600 km depth. This anomaly might also cause a reduction in the effective activation energy for diffusion creep and lead to a viscosity minimum in the mid-lower mantle, in apparent agreement with results from inversion of data related with mantle convection and postglacial rebound.
RESUMEN
The potential of edible mushrooms as an unexploited treasure trove, although rarely included in known food guidelines, is highlighted. Their role in shielding people against the side effects of an unhealthy stylish diet is reviewed. Mushrooms complement the human diet with various bioactive molecules not identified or deficient in foodstuffs of plant and animal sources, being considered a functional food for the prevention of several human diseases. Mushrooms have been widely used as medicinal products for more than 2,000 years, but globally the potential field of use of wild mushrooms has been untapped. There is a broad range of edible mushrooms which remain poorly identified or even unreported which is a valuable pool as sources of bioactive compounds for biopharma utilization and new dietary supplements. Some unique elements of mushrooms and their role in preventative healthcare are emphasized, through their positive impact on the immune system. The potential of mushrooms as antiviral, anti-inflammatory, anti-neoplastic, and other health concerns is discussed. Mushrooms incorporate top sources of non-digestible oligosaccharides, and ergothioneine, which humans are unable to synthesize, the later a unique antioxidant, cytoprotective, and anti-inflammatory element, with therapeutic potential, approved by world food agencies. The prebiotic activity of mushrooms beneficially affects gut homeostasis performance and the balance of gut microbiota is enhanced. Several recent studies on neurological impact and contribution to the growth of nerve and brain cells are mentioned. Indeed, mushrooms as functional foods' nutraceuticals are presently regarded as next-generation foods, supporting health and wellness, and are promising prophylactic or therapeutic agents.
RESUMEN
Understanding the mating patterns of populations of tree species is a key component of ex situ genetic conservation. In this study, we analysed the genetic diversity, spatial genetic structure (SGS) and mating system at the hierarchical levels of fruits and individuals as well as pollen dispersal patterns in a continuous population of Theobroma cacao in Pará State, Brazil. A total of 156 individuals in a 0.56 ha plot were mapped and genotyped for nine microsatellite loci. For the mating system analyses, 50 seeds were collected from nine seed trees by sampling five fruits per tree (10 seeds per fruit). Among the 156 individuals, 127 had unique multilocus genotypes, and the remaining were clones. The population was spatially aggregated; it demonstrated a significant SGS up to 15 m that could be attributed primarily to the presence of clones. However, the short seed dispersal distance also contributed to this pattern. Population matings occurred mainly via outcrossing, but selfing was observed in some seed trees, which indicated the presence of individual variation for self-incompatibility. The matings were also correlated, especially within (Ρ(p(m))=0.607) rather than among the fruits (Ρ(p(m))=0.099), which suggested that a small number of pollen donors fertilised each fruit. The paternity analysis suggested a high proportion of pollen migration (61.3%), although within the plot, most of the pollen dispersal encompassed short distances (28 m). The determination of these novel parameters provides the fundamental information required to establish long-term ex situ conservation strategies for this important tropical species.
Asunto(s)
Cacao/genética , Frutas/genética , Variación Genética/genética , Brasil , Flujo Génico/genética , Genética de Población , Genotipo , Repeticiones de Microsatélite/genética , Polen/genética , Polinización/genética , Reproducción/genéticaRESUMEN
The present study reports mosquito larvicidal potential of green synthesized silver nanoparticles by using Annona glabra leaves (An-AgNPs). Synthesized An-AgNPs were characterized by Ultraviolet-Visible spectroscopy (UV-VIS), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS) technique and Fourier transform infrared spectroscopy (FTIR). Colur change from pale yellow to brick red of the plant extract and AgNO3 solution indicated the formation of An-AgNPs initially. Surface Plasmon Resonance (SPR) band at 435 nm in the UV-Vis confirmed the formation of An-AgNPs. SEM images showed that An-AgNPs were spherical in shape. FTIR proved that An-AgNPs were functionalized with biomolecules in A. glabra leaves. Based on DLS analysis the average size range of synthesized An-AgNPs was determine to be 10-100 nm and 100-1000 nm. Third instar larvae of dengue vector mosquitoes, Aedes aegypti and Aedes albopictus were subjected to larvicidal bioassays in a range of concentrations of An-AgNPs and A. glabra crude aqueous leaf extract (2-10 mg/L). An-AgNPs exhibited very high larvicidal activity against dengue vector mosquito larvae; LC50 value for Ae. aegypti at 24 h exposure to An-AgNPs (Plant extract: AgNO3 1 : 10) 5.29 mg/L; An-AgNPs (Plant extract: AgNO3 2 : 10) 2.43 mg/L while LC50 value for Ae. albopictus at 24 h exposure to An-AgNPs (Plant extract: AgNO31:10) 3.02 mg/L; An-AgNPs (Plant extract: AgNO3 2:10) 2.51 mg/L. LC50 values obtained for A. glabra leaf extract tested against Ae. aegypti and Ae. albopictus are 5.94 mg/L and 5.00 mg/L respectively at 24-hour exposure. This study further revealed that Ae. albopictus is more susceptible than to Ae. aegypti to a given concentration of An-AgNPs and to crude aqueous leaf extract of A. glabra. Larvicidal effect of An-AgNPs is superior to the crude aqueous leaf extract of A. glabra. An-AgNPs is a potent larvicide for dengue vector control.
RESUMEN
Parasitoids of Ceroplastes Gray were surveyed in the State of São Paulo, Brazil. Among the parasitoids reared, seven species of Metaphycus Mercet (Hymenoptera, Encyrtidae) were obtained. Metaphycusanaluciaesp. nov., M. floridensissp. nov., and M. grandissp. nov., are described as new species, and M. ceros Noyes, M. comes Noyes, M. dardanus Noyes, M. opis Noyes are recorded for the first time from Brazil. Ten new host-parasitoid associations are reported: M. analuciaesp. nov. parasitizing C. formicarius Hempel, C. glomeratus Peronti and C. iheringi Cockerel; M. ceros parasitizing C. cirripediformis Comstock; M. comes parasitizing C. formicarius; M. dardanus parasitizing C. glomeratus; M. floridensissp. nov. parasitizing C. floridensis; M. grandissp. nov. parasitizing C. grandis Hempel; and M. opis parasitizing C. glomeratus and C. janeirensis (Gray). A checklist of Metaphycus species associated with Ceroplastes, their distribution and host ranges are summarized and discussed.
Asunto(s)
Hemípteros/parasitología , Avispas/anatomía & histología , Avispas/clasificación , Animales , Brasil , Femenino , Masculino , Clima TropicalRESUMEN
Chromosome numbers in Cyperaceae lower than the typical basic number x = 5 have been described for only three species: Rhynchospora tenuis (n = 2), Fimbristylis umbellaris (n = 3) and Eleocharis subarticulata (n = 3). Eleocharis maculosa is recorded here as the fourth species of Cyperaceae that has a chromosome number lower than 2n = 10, with 2n = 8, 7 and 6. The karyotype differentiation in E. maculosa was studied using conventional staining (mitosis and meiosis), FISH with 45S and 5S rDNA and telomere probes. The results allow us to determine which chromosomes of the chromosome race with 2n = 10 fused to form the remaining reduced numbers, as well as to understand how the symploidy and translocation mechanisms were important in karyotype differentiation and the formation of chromosome races in Eleocharis.
Asunto(s)
Cromosomas de las Plantas/genética , Eleocharis/genética , ADN Ribosómico/genética , Eleocharis/crecimiento & desarrollo , Hibridación Fluorescente in Situ , Cariotipificación , Meiosis/genéticaRESUMEN
Senna (Cassia angustifolia Vahl.) is widely used as a laxative, although potential side effects, such as toxicity and genotoxicity, have been reported. This study evaluated genotoxic and mutagenic effects of senna aqueous extract (SAE) by means of four experimental assays: inactivation of Escherichia coli cultures; bacterial growth inhibition; reverse mutation test (Mutoxitest) and DNA strand break analysis in plasmid DNA. Our results demonstrated that SAE produces single and double strand breaks in plasmid DNA in a cell free system. On the other hand, SAE was not cytotoxic or mutagenic to Escherichia coli strains tested. In effect, SAE was able to avoid H(2)O(2)-induced mutagenesis and toxicity in Escherichia coli IC203 (uvrA oxyR) and IC205 (uvrA mutM) strains, pointing to a new antioxidant/antimutagenic action of SAE.