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Examinando Artículos, Informes Técnicos y presentaciones en Congresos por Autor "Alippi, Adriana Mónica"
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Acceso Abierto The 60th volume of the Journal of Apicultural Research - a look into the past and future(2021) Bouga, Maria; Parejo, Melanie; Alippi, Adriana Mónica; Bobis, Otilia; Brodschneider, Robert; Chantawannakul, Panuwan; Corby-Harris, Vanessa; Dahle, Bjørn; Dimou, Maria; Gajda, Anna; Henriques, Dora; Kandemir, Irfan; Pickard, Robert; Rangel, Juliana; Soroker, Victoria; Stevanovic, JevrosimaThis is the fifth and final issue of the 60th volume of the Journal of Apicultural Research (JAR) - an excellent opportunity to reflect on the highlights in honey bee research and revise the latest developments of our journal. In this extended editorial, we briefly review the importance of JAR in a historical context, followed by the latest developments in the field of honey bee research in terms of main contributors and topics. Then, we look into the latest developments of JAR regarding its impact. Finally, we share our view on the future topics in bee research and conclude by thanking all involved parties for the ongoing success of JAR. - Documento de conferencia
Acceso Abierto Absence of Pseudomonas syringae pv. actinidiae in kiwifruit leaves and flowers from Buenos Aires Province, Argentina(2017) Sánchez, María Clara; Clemente, G.E.; Yommi, A.K.; Alippi, Adriana Mónica; Ridao, AzucenaArgentina has around 1000 ha of kiwifruit orchards in Buenos Aires Province. This country is recognized as free of Pseudomonas syringae pv. actinidiae (Psa). In 2013, the National Sanitary Service (SENASA) imposed measures to avoid the entrance of this pathogen to the kiwifruit production areas. In this way, a vigilance plan was established and the introduction of plant material was regulated. In March 2015, three infected samples with Psa were detected in orchards at the South-East of Buenos Aires Province and they were immediately eradicated by SENASA. The objective of this work was to identify the bacteria associated with kiwifruit leaf spots and flower blights in commercial orchards of Actinidia deliciosa ‘Hayward’ at Buenos Aires Province, during the 2015-2016 growing season. On spring and autumn seasons, plant tissues were collected from a 100 ha area located in the North and South-East of this Province. Bacterial isolates were obtained from flowers and leaves by tissues mashing and inoculation on nutrient agar supplemented with 5% sucrose (NSA). The primary identification of isolates was performed by biochemical and physiological tests. To confirm their identity, duplex-PCR tests were performed, including negative and positive controls (no template and Psa DNA, respectively). From symptomatic and asymptomatic samples, 120 bacterial isolates were obtained. Thirty of these isolates were morphologically similar to Psa, forming white-creamy, convex, domed and mucoid colonies on NSA. Also, all of them were Gram-negative, produced a green fluorescent pigment on King’s B medium and their metabolism was aerobic. However, none of these strains examined produced any bands following the amplification by PCR with Psa specific primers. Our results show the absence of Psa in the analyzed samples. Further studies are needed to identify these non-Psa bacteria associated with kiwifruit leaf spots and flower blights. - Artículo
Embargado Bacillus and Brevibacillus strains as potential antagonists of Paenibacillus larvae and Ascosphaera apis.(2018) Bartel, Laura, Abrahamovich, Eliana; Abrahamovich, Eliana; Mori, Consuelo; López, Ana Claudia; Alippi, Adriana MónicaSpecies of Bacillus and Brevibacillus associated with honey bees are interesting sources of bioactive compounds with potential uses beyond the field of apiculture. Most Bacillus species and related genera produce a broad range of antimicrobial compounds, with activity against bacteria and fungi that include peptides, lipopeptides, bacteriocins, and bacteriocin-like inhibitory substances. By using biological tools, we evaluated the antagonistic activity of 34 bacterial strains against Paenibacillus larvae and Ascosphaera apis, the causal agents of American Foulbrood and Chalkbrood diseases of honey bee larvae, respectively. Data reveal that the antagonistic response was strain-specific, species-specific, and also medium-dependent. By using molecular tools, we investigated the distribution of antimicrobial peptide genes in the antagonist strains. The presence of homologous sequences to nine genes encoding for the synthesis of the antimicrobial peptides bacillomycin L (bmyB), fengycin (fenD), bacilysin (bacA), subtilin (spaS), iturin A (ituD, lpa-14; ituC), and surfactin (sfp; srfAA) was assayed by PCR. The distribution and frequency of these genes within the bacterial antagonists were also variable and strain-dependent, being the most common surfactins (srfAA = 44% and lpa-14 = 38%), iturins (ituD = 47%), and bacilysin (bacA = 32%). Moreover, a positive correlation between presence of antimicrobial peptide genes and antagonism was found taking into account that 85% of the antagonists had at least one of the antimicrobial peptide genes. We also identified those antagonists active against different P. larvae genotypes. To our knowledge, this is the first study of the association between the presence of homologous sequences of antimicrobial peptide genes and antagonism against P. larvae and A. apis strains. - Documento de conferencia
Acceso Abierto Bacterias esporuladas aerobias asociadas con polen apícola(2019) Alippi, Adriana Mónica; Fernández, Leticia A.; López, Ana ClaudiaEl polen apícola es el resultado de la aglutinación del polen de las flores con néctar y sustancias salivares de las abejas, recolectado y transportado por las mismas a la colmena. Es un producto natural expuesto a las condiciones ambientales por lo que contiene una variada microbiota representada principalmente por lactobacillus, levaduras y bacterias esporuladas procedentes de las abejas, de las superficies florales, de otros insectos o de las prácticas apícolas. Las especies de los géneros Bacillus y Paenibacillus, entre otros, son los citados con mayor frecuencia en miel, larvas y abejas adultas. Muchos representantes son ubicuos y, entre ellos, se encuentran especies patógenas como Paenibacillus larvae, agente causal de la enfermedad de las larvas de abejas denominada loque americana y Bacillus cereus sensu lato y Bacillus megaterium, potencialmente enterotóxicos para el hombre. Objetivo: Identificar especies de bacterias esporuladas aerobias presentes en la microbiota de polen obtenido directamente de trampas de apiario. - Documento de conferencia
Acceso Abierto Caracterización microbiológica de polen apícola recolectado en dos períodos de cosecha(2016) Alippi, Adriana Mónica; Fernández, Leticia A.; Susca Tomba, J.; López, F.; Gallez, LilianaEl polen apícola es el resultado del aglutinamiento del polen de las flores efectuado por las abejas mediante néctar y sustancias salivares, y transportado a la colmena en sus patas traseras. Este polen, destinado al consumo humano, se cosecha utilizando trampas ad hoc en las colmenas. Objetivo: Caracterizar microbiológica y fisicoquímicamente muestras de polen provenientes del centro-sur de la provincia de Buenos Aires, Argentina obtenidas al inicio del procesamiento. - Artículo
Acceso Abierto A case of intoxication due to a highly cytotoxic Bacillus cereus strain isolated from cooked chicken(2015) López, Ana C.; Minnaard, Jessica; Pérez, Pablo F.; Alippi, Adriana MónicaOutbreaks of Bacillus cereus infection/intoxication are not commonly reported because symptoms are often mild, and the disease is self-limiting. However, hypervirulent strains increase health risks. We report a case, which occurred in Argentina, of severe food The studied strain was highly cytotoxic, showed high ability to detach Caco-2 cells and was positive for the hblA, hblB, and hblC genes of the hbl complex, bceT, entS and ces. As it is considered that B. cereus emetic cluster evolved from a panmictic population of diarrhoeal strains, B. cereus MVL2011 could constitute an intermediate strain between diarrhoeal and emetic strains. - Artículo
Acceso Abierto Characterization of Argentinean commercial bee pollen intended for human consumption(2023) Fernández, Leticia Andrea; Fernández Echegaray, Victoria; Grandinetti, Gisela; Ledesma González, Matías Francisco; Medici, Sandra; Alippi, Adriana MónicaBee pollen is consumed as a dietary supplement. Its quality parameters are regulated by the Argentine Food Code (AFCode). The present study characterized 10 commercial dehydrated samples from five Argentine provinces to provide information on hygienic quality and health safety. We assessed their microbiological quality, including potential mycotoxins. We also determined their botanical origin and moisture. Results showed that seven out of ten samples presented lower counts of culturable heterotrophic mesophilic bacteria than those allowed by the AFCode. In contrast, all samples showed higher filamentous fungi and yeast counts than the level approved by the AFCode. No fumonisin or deoxynivalenol was detected; we observed only aflatoxin B2 in one sample and ochratoxin A in two. The results of the botanical origin of samples showed that all samples had a predominant pollen type, except one. The microbiological quality of all samples agreed with that required by the AFCode, except filamentous fungi and yeasts. In addition, we found variations among samples from the same province. Therefore, if pollen is intended for human consumption, appropriate hygiene standards must be applied to all bee pollen production operations. - Artículo
Acceso Abierto Characterization of Bacillus larvae White, the causative agent of American Foulbrood of honey bees(1992) Alippi, Adriana MónicaAmerican fouldbrood caused by Bacillus larvae white is recorded for the first time on brood combs of Argentinian hives. The identification of the causative agent was based on disease symptomatology, morphological characters, pathogenicity tests and physiological and biochemical reactions. Studies by scanning electron microscopy showed the occurrence of large flagellar bundles of Bacillus larvae strains growing in biphasic BL medium. An electron microscope survey of the surface configuration of bacterial spores was also made. - Documento de conferencia
Acceso Abierto Correlación entre la presencia de plásmidos y resistencia a tetraciclina en cepas de Bacillus cereus aisladas de miel(2016) Abrahamovich, Eliana; López, Ana Claudia; Alippi, Adriana Mónica. - Artículo
Acceso Abierto Data associated with the characterization and presumptive identification of Bacillus and related species isolated from honey samples by using HiCrome Bacillus agar(Elsevier BV, 2019) Alippi, Adriana MónicaThe dataset described in this paper provides information on the morphological features of 24 different species of the genera Bacillus, Paenibacillus, Brevibacillus, Lysinibacillus, and Rummeliibacilluswhen growing in HiCrome Bacillus agar. The species studied are common contaminants of honey. In support to the recent publication entitled “HiCrome Bacillus agar for presumptive identification of Bacillus and related species isolated from honey samples” (2), a collection of 197 bacterial isolates belonging to 24 different species of aerobic spore-forming bacteria have been screened for their colony appearance and color and any substrate color change of HiCrome Bacillus agar at 24 and 48 h of incubation. Two simple flowcharts utilizing a combination of colony and media characteristics in the chromogenic medium and a set of simple biochemical and morphological tests were developed for quick presumptive identification. - Documento de conferencia
Acceso Abierto Detección de cepas de Bacillus cereus sensu lato con potencial toxicogénico en muestras de polen apícola(2018) López, Ana Claudia; Fernández, Leticia A.; Gallez, Liliana; Alippi, Adriana Mónica. - Artículo
Acceso Abierto Determinación de la dosis óptima de tartrato de tilosina para el control a campo de la loque americana de las abejas(2009) Reynaldi, Francisco J.; Albo, Graciela; Alippi, Adriana Mónica; De Giusti, Marisa RaquelLa loque americana es la enfermedad más grave de origen bacteriano que afecta a las larvas de las abejas melíferas en todo el mundo. En este trabajo, se evaluó la eficacia de 3 dosis diferentes de tartrato de tilosina administradas bajo la forma de “paperpack” en colmenas inoculadas artificialmente con esporas de Paenibacillus larvae, agente etiológico de la enfermedad. La ausencia de larvas con síntomas clínicos demostró que las dosis de 1.000 mg y 1.200 mg de tilosina fueron las más efectivas in vivo protegiendo a las colmenas por un período de hasta 365 días desde la aplicación del tratamiento. Paralelamente, se encontró una mayor efectividad de la dosis de 1.000 mg con el agregado de gelatina de cereza como saborizante. La utilización del tartrato de tilosina en Argentina puede ser una herramienta alternativa para el control de la loque americana a campo, principalmente en colmenares en los cuales se haya detectado resistencia a tetraciclina. Un tratamiento otoñal de 1.000 mg de p.a. de tilosina con saborizante junto con otras pautas de manejo facilitaría el control integrado de la enfermedad evitando la difusión de cepas del patógeno resistentes a tetraciclina. - Documento de conferencia
Acceso Abierto Diagnosis and detection of different genotypes of Paenibacillus larvae, the causal agent of American Foulbrood disease(2017) Alippi, Adriana MónicaAmerican foulbrood (AFB) is the most contagious and destructive infectious disease affecting the larval and pupal stages of honey bees (Apis mellifera) and other Apis species. The causative agent, Paenibacillus larvae, is a Gram-positive bacterium that can produce over one billion spores in each infected larva. AFB occurs in temperate or subtropical regions throughout the world and leads to huge losses not only in the apicultural economy but also in pollination rates since Apis mellifera is the most widely used actively managed pollinator in the world. The disease is classified within the World Organization for Animal Health (OIE) list and considered to be of socio-economic impact and significance in the international trade of bees and bee products. Only bacterial spores are capable of inducing the infection. Spores can remain viable for long periods and survive adverse conditions (desiccation, high temperatures, ultraviolet light exposure) and contact with standard disinfectants. The spread of the disease is facilitated by normal beekeeping practices, including exchanging hive components between colonies, maintaining many hives in a confined area, and trading queens, package bees and honey - Documento de conferencia
Acceso Abierto Diferenciación rápida de especies de Bacillus, Brevibacillus, Paenibacillus, Lysinibacillus y Rummeliibacillus aisladas de miel mediante PCR-RFLP(2018) López, Ana Claudia; Alippi, Adriana MónicaLas bacterias mesófilas del género Bacillus y otros géneros relacionados son las especies esporuladas que aparecen con mayor frecuencia en muestras de miel. Una misma muestra puede contener más de una especie de este grupo, por lo que el empleo de medios de cultivo semi-selectivos y diferenciales y pruebas microbiológicas posteriores para llegar a una correcta identificación resulta complicada y laboriosa. Por otra parte, si bien la secuenciación completa del gen 16S rDNA permite la identificación de las distintas especies bacterianas presentes en una muestra, secuenciaciones parciales en el caso de especies estrechamente relacionadas pueden resultar en una identificación errónea. El estudio de los polimorfismos por restricción de la longitud de los fragmentos de ADN generados por la digestión de enzimas endonucleasas en combinación con PCR (PCR-RFLP) permite detectar diferencias entre las secuencias de alelos. - Artículo
Acceso Abierto Diversidad de cepas de Agrobacterium rubi aisladas de arándanos(Asociación Argentina de Microbiología, 2014) Abrahamovich, Eliana; López, Ana C.; Alippi, Adriana MónicaSe estudió la diversidad de una colección de cepas de Agrobacterium rubi aisladas de arándanos provenientes de distintas regiones de la República Argentina estableciendo su grado de heterogeneidad mediante pruebas microbiológicas clásicas y técnicas de biología molecular. Los resultados obtenidos en las pruebas bioquímicas y fisiológicas, así como mediante rep-PCR y RFLP del gen 23S ADNr, demostraron una alta variabilidad intraespecífica, tanto fenotípica como genotípica. - Artículo
Embargado Diversity among strains of four Agrobacterium species isolated from diseased plants of blueberry (Vaccinium corymbosum) in Argentina.(2012) Alippi, Adriana Mónica; Lopez Ana Claudia; Balatti, Pedro AlbertoThe aim of this study was to isolate, identify and analyze the diversity of the causative agents of crown galls and hairy roots from symptomatic plants ofVaccinium corymbossumby means of biological, biochemical and molecular tools. All the bacteria isolated from blueberries (n = 78) were found to beAgrobacteriumsince they grew on three differential media, provoked cell and/or root proliferation on Kalanchoe, and contained a 730bp partial sequence that codes for virulence genes within thevirC operon found on Ti and/or Ri plasmids. Isolates were highly variable considering the ERIC-PCR patterns as well as biochemical reactions and were all represented by 7 different restriction patterns of the 16SrDNA. While most of the isolates belonged toAgrobacteriumbv. 1 (n = 33) orAgrobacteriumbv. 2 (n = 31) only fourteen wereAgrobacterium rubi.A representative isolate of each of these three groups was further identified by sequencing the approximately 400bp 16SrDNA. We concluded thatVacciniumplants are particularly susceptible toAgrobacteriumbv. 1,Agrobacteriumbv. 2, and also toAgrobacterium rubi.To our knowledge this is the first survey ofAgrobacteriumaffecting blueberries in Argentina. - Artículo
Acceso Abierto Diversity of aerobic spore-forming bacteria isolated from fresh bee pollen intended for human consumption(2021) Alippi, Adriana Mónica; López, Ana Claudia; Fernández, Leticia A.Bee pollen is the result of the agglutination of pollen grains collected from flowers and mixed with nectar and salivary secretions by honey bees. Bee pollen is a natural product exposed to environmental conditions and also provides a unique microhabitat for yeasts and bacterial com munities. We analyzed 30 fresh bee pollen samples obtained from the main producing areas of Argentina to identify aerobic-spore-forming bacteria. We obtained 73 isolates belonging to 16 different species through isolation on selective and differential media, morphological and bio chemical tests, and PCR and RFLP analysis of genes encoding 16S rRNA. Our data revealed that Bacillus cereus sensu stricto was the most predominant species (50%), followed by Bacillus mega terium (40%) and Bacillus subtilis (40%), respectively. In a minor proportion, Paenibacillus poly myxa (20%), Paenibacillus larvae (17%), Bacillus pumilus (13%), Bacillus licheniformis (13%), Bacillus amyloliquefaciens (10%), Lysinibacillus sphaericus (7%), Bacillus coagulans (7%), Rummelliibacillus stabekisii (7%), Bacillus thuringiensis (7%), Bacillus clausii (3%), Paenibacillus alvei (3%), Bacillus simplex (3%), and Paenibacillus amylolyticus (3%) were also found. Our results showed that Argentinean bee pollen could transmit honey bee diseases due to the presence of viable spores of P. larvae and also spores of toxicogenic B. cereus s.s. and B. megaterium strains. - Artículo
Embargado Diversity of Bacillus megaterium isolates cultured from honeys(Elsevier, 2009) López, Ana C.; Alippi, Adriana MónicaBacillus megaterium isolates recovered from Argentinean honeys (n ¼ 48) were compared with isolates recovered from honey from other countries (n ¼ 4) and with strain NRRL B-939. All the isolates and the NRRL strain were characterized using rep-PCR fingerprinting with primers BOX-, REP- and ERIC-; restriction fragment length polymorphism analysis of a 16S rRNA gene fragment (16S rRNA PCR/RFLP), and morphological and biochemical tests. There was a high degree of diversity, both phenotypic and genotypic among the isolates of B. megaterium. Our results not only show considerable levels of diversity among isolates of B. megaterium analyzed here but also that repetitive sequences such as BOX, ERIC and REP are reliable tools to characterize isolates at the genomic level. Haemolytic activity was shown by 77% of the isolates, as b-haemolysis (40 isolates) or a-haemolysis (one isolate). Within the b-haemolytic group, 10% of isolates produced a discontinuous haemolytic pattern, which is usually correlated with enterotoxin activity in other bacterial species. In addition, coagulase activity was detected in 74% of 53 isolates tested suggesting a pathogenic activity not ordinarily reported as a property of B. megaterium. According to our knowledge, this is the first report of phenotypic and genotypic characterization of B. megaterium isolates from honey. - Artículo
Acceso Abierto Draft genome sequence of Bacillus thuringiensis strain m401 isolated from honey in Argentina(2018) Abrahamovich, Eliana; Franco, Mario Emilio Ernesto; López, Ana Claudia; Alippi, Adriana Mónica; Balatti, Pedro AlbertoWe report here the 6,092,003-bp draft genome sequence of Bacillus thuringiensis strain m401, a tetracycline-resistant isolate recovered from honey. The isolate contained three plasmids of 8,307 bp, 9,934 bp, and 69,561 bp and a tetracycline resistance gene with high homology to tet45 in a contig of 236,180 bp. - Artículo
Acceso Abierto Enterotoxigenic gene profiles of Bacillus cereus and Bacillus megaterium isolates recovered from honey(Asociación Argentina de Microbiología, 2010) Alippi, Adriana Mónica; López, Ana Claudia; Alippi, Adriana MónicaOne hundred and thirty two Bacillus cereus and 52 Bacillus megaterium isolates from honeys were evaluated for the presence of genes encoding enterotoxin HBL, enterotoxin-T, cytotoxin K and the NHE complex, respectively. The relationship between hemolytic and coagulase activity and its correlation with the presence of the four mentioned enterotoxins was determined by principal component analysis (PCA). PCA in B. cereus revealed a positive correlation among free coagulase, hemolysis and the presence of genes hblA, hblB, hblC, hblD (HBL complex) and bceT (enterotoxin-T), but no correlation with the clumping factor (bound coagulase) and the presence of sequences of the NHE complex. On the other hand, PCA in B. megaterium showed a high positive correlation between coagulase (bound and free) and the haemolytic activity but no correlation in relation to the presence of genes of the HBL complex, cytotoxin K, enterotoxin T and the NHE complex. To our knowledge, this is the first report of the detection of cytotoxin K and of the NHE complex genes in B. megaterium. The relationship between the coagulase activity and the presence of virulence factors has not been described before in the genus Bacillus, being this work the first report of this correlation. Interestingly, the presence of the cytK gene was almost independent of the presence of the rest of virulence factors herein analyzed both in B. cereus and B. megaterium populations. Our results suggest that honey could be a possible vehicle for foodborne illness due to the presence of toxigenic B. cereus and B. megaterium strains containing different virulence factors.
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