Economic model for obtaining cyclodextrins from commercial cgtase

A repetitive batch process was employed followed by membrane ultrafiltration system to produce low-cost cyclodextrins (CDs) using commercial enzymes Toruzyme® cyclomaltodextrin glucanotransferase (CGTase) and its kinetic parameters were determined. The ultrafiltration system enabled the removalof inhibitory products from the reaction medium, allowing the enzyme to be recovered for reuse. A 10 kDa membrane was used to separate the different CDs produced by the CGTase. The substrates evaluated were maltodextrin, corn starch and cassava starch at 5, 10 and 15% (w/V), in the presence and absence of 10% (V/V) ethanol. After reaction for 132 h, 10% (w/V) cassava starch in the presence of ethanol provided the best results with 32.1 mg/mL of ß-CD. Maximum production occurred after 72 h of reaction, with a yield of 87.4% of ß-CD and an α-CD, ß-CD and γ-CD production ratio of 1:1:0.08 g, respectively. When eight repetitive batches of 72 h followed by ultrafiltration and crystallization of ß-CD were performed, 2.1 g of precipitate was obtained with a purity of 67.6% ß-CD. The supernatant from the crystallization process was lyophilized and resulted in 35.3% α-CD. The developed model can be used industrially for the production of low cost CDs from easily obtained raw material

Sandfly fauna and behavior (Diptera: Psychodidae) in municipalities of the Mesoregion North Pioneer of Paraná, Brazil

Abstract The occurrence of cutaneous leishmaniasis (CL) in the municipalities of Jaboti, Japira, Pinhalão, and Tomazina in the North Pioneer of the State of Paraná, where this disease is endemic, prompted the investigation of sandfly fauna, their population changes throughout the year, and their behavior in and around human accommodation. In these municipalities, the collection of sandflies was conducted using Falcão traps from 7 pm to 6 am once a month. 32,994 sandflies, 18,442 males and 14,552 females, were collected and represented by the species Brumptomyia brumpti, Brumptomyia cunhai, Evandromyia correalimai, Evandromyia cortelezzii, Expapillata firmatoi, Micropygomyia ferreirana, Migonemyia migonei, Nyssomyia neivai, Nyssomyia whitmani, Pintomyia fischeri, Pintomyia monticola, Pintomyia pessoai, and Psathyromyia bigeniculata. Ny. neivai (SISA = 0.9808) predominated in Japira (46.9%), Pinhalão (53.1%), and Tomazina (38.9%), while Ny. whitmani (SISA = 0.9423) predominated in Jaboti (53.8%). Most sandflies were captured in domestic animal shelters, with a peak in September. The high number of sandflies collected in domestic animal shelters, species richness, and presence of species involved in the epidemiology of CL reveal the need for permanent entomological surveillance in the municipalities mentioned. The use of phlebotomine control measures in these municipalities should be considered in conjunction with the anthropogenic actions that have resulted in changes to sandfly fauna and behavior.

Different strategies for cyclodextrin production: Ultrafiltration systems, CGTase immobilization and use of a complexing agent.

The study comparatively evaluated diverse strategic models of cyclodextrin (CD) production by the CGTase of Bacillus firmus strain 37: continuous production and repetitive batches in ultrafiltration systems; immobilization of CGTase on curdlan and vegetable sponge natural supports; the use of the glycyrrhizin complexing agent to modulate CGTase selectivity in favor of γ-CD production. All strategies had in common the possibility of separation of CGTase from its inhibitory products and its reuse. In the continuous production model, at 48 h of assay, the highest productivity and selectivity for ß-CD were obtained, 1.47 mmol/L/h and 92.8%, respectively. Glycyrrhizin was able to modulate the production of γ-CD with selectivity of 61.2% for 30-h batches. The comparative evaluation of the different strategic models for obtaining CDs showed particularities that should be considered, and most of the models studied returned satisfactory yields as well as excellent selectivity.

Mathematical modelling and kinetic study for CD production catalysed by Toruzyme® and CGTase from Bacillus firmus strain 37.

A new mathematical model was developed for the kinetics of α-, ß- and γ-cyclodextrin production, expanding an existing model that only included the production of ß- and γ-cyclodextrins, because a detailed kinetic modelling of the reactions involved allows the manipulation of the process yields. The kinetic behaviour of the commercial enzyme Toruzyme® was studied with maltodextrin as substrate at different concentrations and for CGTase from Bacillus firmus strain 37 at a concentration of 100 g L-1. The mathematical model showed a proper fit to the experimental data, within the 24-h period studied, confirming that the considered hypotheses represent the kinetic behaviour of the enzymes in the reaction medium. The kinetic parameters generated by the model allowed reproducing previous observed qualitative tendencies as it can be seen that changing experimental conditions in the reaction process such as enzyme and substrate concentrations results in large changes in the enzyme kinetics and using high substrate concentrations does not guarantee the highest conversion rates due to enzyme inhibition and reverse reactions. In addition, this new mathematical model complements previous qualitative observations enabling the manipulation of the direct and reverse reactions catalysed by the enzyme by adjusting the reaction conditions, to target quantitative results of increased productivity and better efficiency in the production of a desired cyclodextrin.

Use of FT-IR, FT-Raman and thermal analysis to evaluate the gel formation of curdlan produced by Agrobacterium sp. IFO 13140 and determination of its rheological properties with food applicability.

Curdlan is a linear polysaccharide composed of glucose units joined by ß-(1,3) bonds that possesses unique gelation properties. This study aimed to characterize the structure and evaluate the gelling properties of curdlan produced by Agrobacterium sp. IFO 13140 and its gels, as well as apply it in food. FT-Raman analysis highlighted the structural changes that occurred during the formation of gels, with variations related to the hydrogen bonds and hydrophobic interactions, which occur with the formation of the low-set and high-set gels, respectively. Rheological analysis showed that the pre-gelled commercial curdlan and the curdlan produced by Agrobacterium sp. IFO 13140 differed in terms of gelation properties, which depends of the degree of polymerization of the polysaccharide, but when applied to pasta products, both improved the texture parameters. The curdlan gels were found to have great potential as gelling agents to improve texture, water retention capacity and stability of food products.

Description of recovery method used for curdlan produced by Agrobacterium sp. IFO 13140 and its relation to the morphology and physicochemical and technological properties of the polysaccharide.

Curdlan is a linear polysaccharide considered a dietary fiber and with gelation properties. This study evaluated the structure, morphology and the physicochemical and technological properties of curdlan produced by Agrobacterium sp. IFO 13140 recovered by pre-gelation and precipitation methods. Commercial curdlan submitted or otherwise to the pre-gelation process was also evaluated. The data obtained from structural analysis revealed a similarity between the curdlan produced by Agrobacterium sp. IFO 13140 (recovered by both methods) and the commercial curdlans. The results showed that the curdlans evaluated differed significantly in terms of dispersibility and gelation, and only the pre-gelled ones had significant potential for food application, because this method influence on the size of the particles and in the presence of NaCl. In terms of technological properties, the curdlan produced by Agrobacterium sp. IFO 13140 (pre-gelation method) had a greater water and oil holding capacity (64% and 98% greater, respectively) and a greater thickening capacity than the pre-gelled commercial curdlan. The pre-gelled commercial curdlan displayed a greater gelling capacity at 95°C than the others. When applied to food, only the pre-gelled curdlans improved the texture parameters of yogurts and reduced syneresis. The curdlan gels, which are rigid and stable in structure, demonstrated potential for improving the texture of food products, with potential industrial use.

Insulin complexation with hydroxypropyl-beta-cyclodextrin: Spectroscopic evaluation of molecular inclusion and use of the complex in gel for healing of pressure ulcers.

The pressure ulcer healing is a complex process and difficult to be achieved. Insulin is known to promote wound healing, and when complexed with cyclodextrin presents improved solubility, stability and biological activity. Complexation of insulin with hydroxypropyl-beta-cyclodextrin (HPßCD) was performed in this work through the coprecipitation method, providing the inclusion complex (HPßCD-I). The spectroscopic techniques used to analyze the complex were H(1) NMR, FT-Raman and FT-IR/ATR. A gel containing the HPßCD-I complex was prepared and a clinical study was conducted in patients with pressure ulcers. The spectroscopic techniques allowed to confirm the complex formation through the inclusion of aromatic amino acids, such as phenylalanine present in the HPßCD cavity. Data obtained from the FT-Raman and FT-IR/ATR techniques, combined with the H(1) NMR results, showed the effectiveness of these techniques in evaluating the inclusion complex of HPßCD with insulin. Clinical studies demonstrated tissue revitalization and a trend (p=0.06) for a significant difference between the healing effect of the control gel and that with HPßCD-I complex. The creation of the gel prepared with insulin and HPßCD-I complex and its use in patients with pressure ulcers appears to be promising in wound healing and its possible use in hospital care.

Ultrafiltration system for cyclodextrin production in repetitive batches by CGTase from Bacillus firmus strain 37.

This study aimed to improve the yield of cyclodextrins (CDs) production in repetitive batches. An innovative ultrafiltration system was used to remove the inhibitory products that accumulated in the medium and to recover the enzyme. The assays were performed with the CGTase from Bacillus firmus strain 37 in purified, semi-purified, and crude extract forms. Maltodextrin (10% w/v) and corn starch (5% w/v) were used as substrates. After eight repetitive 24-h batches, the yield of ß-CD obtained with the purified enzyme and the corn starch substrate was 0.54 mmol/L/h, which was 36% greater than that observed with the 10% maltodextrin substrate. The crude CGTase extract with the corn starch substrate showed a productivity of 0.38 mmol/L/h, which was 29% lower than using the purified enzyme and the corn starch substrate but 7% higher than using the purified enzyme and the maltodextrin substrate. The crude extract, assayed with the corn starch substrate in the presence of 10% ethanol reached 0.43 mmol/L/h productivity, which was 12% higher compared to the assay without ethanol. The semi-purified enzyme was assayed with the corn starch substrate in the presence of 10% ethanol for eight batches lasting 12 h and an excellent selectivity for the ß-CD was obtained, reaching a mean percentage of 96.0%. Therefore, this ultrafiltration system enabled several batches of CD production, with efficient removal of products inhibitory to the CGTase and recovery of the enzyme. The possibility of industrial application of this system is promising.

Sandfly frequency in a clean and well-organized rural environment in the state of Paraná, Brazil.

INTRODUCTION: Sandflies caught in Santa Juliana Farm in Sarandi, State of Paraná, Brazil, were assessed in terms of their fauna, seasonality, and frequency in the homes and in shelters of domestic animals around the homes, as well as in the nearby forest. METHODS: In Santa Juliana Farm, there are no records of cases of ACL, differing from other relatively clean and organized areas where surveys of sandflies have been conducted in Paraná. Samples were collected with Falcão light traps, fortnightly from 22:00 to 02:00 hours, from November 2007 to November 2008. RESULTS: A total of 4,506 sandflies were captured, representing 13 species, predominantly Nyssomyia whitmani (71.8%). More sandflies were collected in the forest (52.6%) than outside the forest (residences and pigsty) (47.4%). However, Ny. whitmani was collected in greater numbers outside (38.3%) than inside the forest (33.5%). Most sandflies were collected in the warmer months and during periods with regular rainfall. CONCLUSIONS: The results suggest that cleaning and organization around the houses could reduce sandfly population in peridomicile. Constructing shelters for animal at a distance of approximately 100m from domiciles is recommended to prevent the invasion of sandflies, as this farm has an area of preserved forest, with wild animals and sandflies present to maintain the enzootic cycle of Leishmania.

Sandfly frequency in a clean and well-organized rural environment in the state of Paraná, Brazil / Frequência de flebotomíneos em ambiente rural com boas condições de limpeza e organização, no estado do Paraná, Brasil

INTRODUCTION: Sandflies caught in Santa Juliana Farm in Sarandi, State of Paraná, Brazil, were assessed in terms of their fauna, seasonality, and frequency in the homes and in shelters of domestic animals around the homes, as well as in the nearby forest. METHODS: In Santa Juliana Farm, there are no records of cases of ACL, differing from other relatively clean and organized areas where surveys of sandflies have been conducted in Paraná. Samples were collected with Falcão light traps, fortnightly from 22:00 to 02:00 hours, from November 2007 to November 2008. RESULTS: A total of 4,506 sandflies were captured, representing 13 species, predominantly Nyssomyia whitmani (71.8 percent). More sandflies were collected in the forest (52.6 percent) than outside the forest (residences and pigsty) (47.4 percent). However, Ny. whitmani was collected in greater numbers outside (38.3 percent) than inside the forest (33.5 percent). Most sandflies were collected in the warmer months and during periods with regular rainfall. CONCLUSIONS: The results suggest that cleaning and organization around the houses could reduce sandfly population in peridomicile. Constructing shelters for animal at a distance of approximately 100m from domiciles is recommended to prevent the invasion of sandflies, as this farm has an area of preserved forest, with wild animals and sandflies present to maintain the enzootic cycle of Leishmania.

INTRODUÇÃO: Relatam-se os resultados de coletas de flebotomíneos na Fazenda Santa Juliana, município de Sarandi, Estado do Paraná, Brasil, onde se verificou a fauna, a sazonalidade e a frequência desses insetos nos ambientes florestal e extraflorestal. MÉTODOS: O trabalho foi realizado nesta fazenda pela inexistência de registro de casos de LTA e por diferir de outras áreas onde foram realizadas pesquisas com flebotomíneos, no Paraná, e pela limpeza e organização do peridomicílio. As coletas foram realizadas com sete armadilhas luminosas de Falcão, quinzenalmente das 22 às 2 horas, de novembro de 2007 a novembro de 2008. RESULTADOS: Foram capturados 4.506 flebotomíneos de 13 espécies, com predomínio de Nyssomyia whitmani (71,8 por cento). Coletou-se maior proporção de flebotomíneos no ambiente florestal (52,6 por cento) do que no extraflorestal (residências e chiqueiro) (47,4 por cento), entretanto a proporção de Ny. whitmani coletada foi maior no ambiente extraflorestal (38,3 por cento) do que no florestal (33,5 por cento). A maioria dos flebotomíneos foi coletada nos meses mais quentes e com quedas regulares de chuva. CONCLUSÕES: Os resultados sugerem que a limpeza e a organização do peridomicílio podem auxiliar a reduzir a população de flebotomíneos no domicílio e no peridomicílio, recomendando-se que a construção de abrigos de animais guarde a distância aproximada de 100m das residências, para evitar a invasão desses insetos, uma vez que nesta fazenda existe uma área de mata de preservação, com a presença de animais silvestres e flebotomíneos, que mantem o ciclo enzoótico de Leishmania.