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Lutzomyia intermedia (Diptera: Psychodidae) features as one of the main vectors that are involved in the transmission of American cutaneous leishmaniasis (ACL) in the Neotropical region. However, genetic studies involving this taxon are still incipient and important for understanding the level of variability of different populations, their role, and implications as vectors. The aim of this study was to determine the level of genetic diversity of L. intermedia present in the Ribeira River Valley, an area of ACL transmission in the state of Paraná, Brazil, through the Random amplified polymorphic DNA (RAPD). Two municipalities were chosen to collect sand flies: Cerro Azul (new transmission area of the ACL) and Adrianópolis (endemic area of the ACL). The insects were captured in the house, in the peridomicile and in the wild (forest). Two of the used markers made it possible to estimate the polymorphism of the studied populations, resulting in 40 genotypes, most of them from peridomicile. The dendrogram generated by the analysis with the primer A10 showed different degrees of similarity, suggesting that there may be gene flow in the studied populations. The Principal Coordinate Analysis (PCO) with the A2 primer, was useful in grouping L. intermedia according to its ecological and geographical origin. There was no distinction between the lineages composing the L. intermedia complex. The results of this study, with the record of great genotypic diversity in L. intermedia, may contribute to explain the maintenance of the life cycle of Leishmania braziliensis (Kinetoplastida: Trypanosomatidae) in the region. RESUMEN Lutzomyia intermedia (Diptera: Psychodidae) es uno de los principales vectores que participan en la transmisión de leishmaniasis cutánea americana (LCA) en la región Neotropical. A pesar de que aún los estudios genéticos que involucran a este taxón son incipientes, tienen una gran importancia para comprender el nivel de variabilidad de las diferentes poblaciones y sus implicaciones en su papel vectorial. El objetivo de este estudio fue determinar el nivel de diversidad genética de L. intermedia presente en el Valle del Río Ribeira, área de transmisión de LCA en el estado de Paraná, Brasil, mediante RAPD (ADN polimórfico amplificado aleatoriamente). Los flebótomos fueron recolectados en los municipios Cerro Azul (nueva área de transmisión de LCA) y Adrianópolis (área endémica de LCA), donde fueron capturados en ambientes residenciales, en el peridomicilio y en el bosque. Dos de los marcadores utilizados permitieron estimar el polimorfismo en las poblaciones estudiadas con la obtención de 40 genotipos, la mayoría de ellos en el peridomicilio. El dendrograma generado por el análisis con el cebador A10 mostró diferentes grados de similitud, lo que sugiere que puede haber flujo gènico en las poblaciones. El Análisis de Coordenadas Principales (PCO) con el cebador A2 fue útil para agrupar L. intermedia según su origen ecológico y geográfico. No hubo distinción entre los linajes que componen el complejo L. intermedia. Los resultados de este estudio, con el registro de gran diversidad genotipica en L. intermedia, pueden contribuir a explicar el mantenimiento del ciclo biológico de Leishmania braziliensis (Kinetoplastida: Trypanosomatidae) en la región.

The aims of this study were to optimize the medium composition, culture conditions and define a bioprocess using types of bioreactor to increase phytase production through submerged cultivation by Ganoderma sp. MR-56. Metal salts, carbon and nitrogen sources had been evaluated upon the overall enzyme production on wheat bran broth. The results showed increase of 81, 95 and 36% of phytase activity, compared to control, by the supplementation of soybean molasses, yeast extract and CaCl 2 , respectively. Phytase activity in optimized medium reached 14.5 U mL ⿿1 , a 5.8-fold increase compared to control. Also, at optimized medium, the associated effects of culture conditions as vessel type and aeration were achieved at 30 °C, pH 6.0 and 3% inoculum rate. Maximum phytase production was obtained in Dreschel bottles at 2.0 vvm, which resulted in 20.9 U mL ⿿1 at 264 h and productivity of 0.08 U mL ⿿1 h ⿿1 , while 11.1 U mL ⿿1 in Erlenmeyer Flasks at 96 h (productivity of 0.12 U mL ⿿1 h ⿿1 ). The greatest productivity was 0.14 U mL ⿿1 h ⿿1 obtained in stirred tank reactor and reaching 10.3 U mL ⿿1 of phytase activity at 72 h. Overall, was proven that Ganoderma sp. MR-56 can successfully produce phytase in different bioreactors through submerged cultivation using a by-product medium.

The aim of this study was to investigate the occurrence of anti-Leishmania spp. antibodies in dogs from localities in the city of Foz do Iguaçu, Paraná state, Brazil, on the border with Argentina and Paraguay. Blood samples dogs were collected to perform the following serologic tests: immunochromatographic DPP® rapid test, indirect immunoenzymatic assay (ELISA) and indirect immunofluorescence assay (IFA). In 2012, 285 dogs were analyzed on Argentina border, and in 2013, serum samples from 396 dogs on the border of Paraguay were collected. Using ELISA for screening and IFA for the confirmatory test, the results showed that the antibody prevalence was 1.8% (5/285) on the border of Argentina and 3.0% (12/396) on Paraguay border. When using the DPP® for screening and ELISA as a confirmatory analysis, we observed a seroreagent prevalence in dogs of 2.5% (7/285) on Argentina border and 5.1% (20/396) on Paraguay border. The non-public collection of domestic waste (p= 0.0004) was shown to be associated with leishmaniasis. This study shows the presence of leishmaniasis and suggest the emergence of canine visceral leishmaniasis in state of Paraná due to the confirmed occurrence of seroreactive dogs on Argentina and Paraguay border, which has environmental and geographical characteristics that favor the spread of the parasite. Resumo O objetivo deste estudo foi investigar a ocorrência de anticorpos anti- Leishmania spp. em cães da cidade de Foz do Iguaçu, estado do Paraná, Brasil, fronteira com a Argentina e o Paraguai. Amostras de sangue de cães foram coletadas para realização dos seguintes testes sorológicos: teste rápido imunocromatográfico DPP®, ensaio imunoenzimático indireto (ELISA) e ensaio de imunofluorescência indireta (IFI). Em 2012, 285 cães foram analisados na fronteira com Argentina e, em 2013, amostras de soro de 396 cães na fronteira com o Paraguai. Utilizando ELISA para triagem e IFA para o teste confirmatório, os resultados mostraram uma prevalência de anticorpos de 1,8% (5/285) na fronteira da Argentina e 3,0% (12/396) na fronteira com o Paraguai. Ao usar o DPP® para triagem e ELISA como uma análise confirmatória, observou-se uma prevalência de cães sororreagentes de 2,5% (7/285) na fronteira com a Argentina e 5,1% (20/396) na fronteira com o Paraguai. A não coleta pública de lixo doméstico (p = 0,0004) mostrou-se associada à leishmaniose. Este estudo demonstra a presença de leishmaniose e sugere a emergência da leishmaniose visceral canina no estado do Paraná devido à ocorrência de cães sororreagentes na fronteira Argentina e Paraguai, que possuem características ambientais e geográficas que favorecem a disseminação do parasito.

Leishmaniosis is a disease that can manifest in two different forms, visceral or cutaneous. The prevalence is estimated to be 12 million people in 98 countries, with about 1.5 million new cases annually. Existing treatments for leishmaniosis are invasive, require long-term care, and result in severe side effects. Biotechnological strategies are needed to develop better pharmaceuticals against leishmaniosis. In this chapter, the current state of art of drugs for the treatment of leishmaniosis is reviewed and perspectives to develop new antileishmanials by biotechnological methods are proposed.

Eco-friendly sugarcane production is constantly faced with growing demands for increased productivity. Current biotechnology, based on growth promotion through bacterial inoculants, presents us with the opportunity to increase production without an adverse environmental impact. To this end, plant growth-promoting bacteria (PGPB) with their diverse agricultural characteristics, like nitrogen fixation and production of plant regulators, are a good choice in achieving this goal. Characterization of the abilities of different strains will define their potential use, which for the most part is not limited to a single desirable feature. Therefore, our aim was to contribute to the present understanding of the principal activities of PGPB in sugarcane, to provide some simple and common methods for selecting them, and to draw attention to sugarcane breeding for selection of responsive clones for PGPB inoculation.

Citric pulp is an agro-industrial residue from the citrus processing industry with low inorganic phosphorus content applied in animal feed. A new bioprocess was developed to produce and purify a new phytase generated on citric pulp fermentation by Aspergillus niger FS3. The phytase was purified by cationic-exchange, anionic-exchange chromatography and chromatofocusing steps. From SDS–PAGE analysis, the molecular weight of the purified phytase was calculated to be 108 kDa. The phytase had an optimum pH of 5.0–5.5 and an optimum temperature of 60°C. The phytase displayed high affinity for phytate, and the Km was 0.52 mM. The purified phytase was sufficiently able to withstand pelleting temperatures, retaining sufficiently high phytate-degrading activity.

Xylanases are glycosidases mainly responsible for the hydrolysis of β-1,4 linkages in xylan. Xylanase was produced in this work by solid-state fermentation using agro industrial residues with Aspergillus niger strain, which was screened through qualitative and quantitative methods. Extraction processes with different solvents were evaluated. Solvent volume, time, and agitation speed (shaker) were optimized using statistical designs. Drying studies of the solid fermented material were also conducted in a laboratory oven where the following conditions were applied: 42°C and 50°C for 20 h and 80°C for 1 h; 50°C and 75°C for 6 and 3 h, respectively. Best extraction conditions were 37 mL of solvent composed by NaCl solution (0.9%) with Tween 80 (0.1%) in 3 g of cultured material with agitation at 133 rpm in shaker for 4 min. Highest xylanase activity was 2,327 IU/gdm. The drying at 42°C for 20 h provided a better maintenance of xylanase activity (58% of xylanase activity).

The study of xylanase production was conducted by Streptomyces viridosporus T7A in submerged (SmF) and solid-state fermentation (SSF), using agro-industrial residues and sub-products. Napier grass, sugarcane bagasse and soybean bran were used as carbon source, substrate/support, and nitrogen source, respectively. In SmF, Napier grass (1% v/w) supplemented with soybean bran, hydroxyethylcellulose and B complex vitamins were used. Soybean bran (1.5 % w/v), B complex vitamins (0.1%), and hydroxyethilcellulose (0.15%) led to an increase in xylanase production (23.41 U/mL). In SSF, the effects of the following parameters were studied: substrate composition (sugarcane bagasse, Napier grass and soybean bran), initial moisture, and inoculum rate. In SSF, the highest xylanase activity (423.9 U/g) was reached with: 70 % sugarcane bagasse, 20% Napier grass and 10% soybean meal, 90% of moisture, and 10(7)/g substrate.A produção de xilanase por Streptomyces viridosporus T7A foi realizada em fermentação submersa (FSm) e fermentação no estado sólido (FES) utilizando resíduos e sub-produtos agroindustriais. Capim Napier, bagaço de cana e farelo de soja foram empregados como fonte de carbono, suporte/substrato e fonte nitrogênio, respectivamente. Em FSm, o capim Napier (1 % p/v) foi suplementado com farelo de soja (1,5 % p/v), hidroxietilcelulose (0,15 %) e vitaminas do complexo B (1,5 %) sendo que a produção de xilanase atingiu 23.41 U/mL. Em FES, o efeito dos seguintes parâmetros foi estudado: composição do substrato (bagaço de cana, Capim Napier e farelo de soja), umidade inicial, aeração e taxa de inoculação. A mais elevada produção de xilanase (423,9 U/g) foi atingida com 70% bagaço de cana, 20% de capim Napier e 10 % farelo de soja, 90 % de umidade inicial e 10(7) células/g substrato.