Vanete Thomaz-Soccol

Potential carbon dioxide fixation by industrially important microalgae

The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbon dioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbon dioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii.

Lutzomyia whitmani (Diptera: Psychodidae) as vector of Leishmania (V.) braziliensis in Paraná state, southern Brazil

The phlebotomine sandflies in the northern areas of the state of Paraná, Brazil, particularly those in the ‘16a’ health region, were investigated over a 3-year period. Using CDC light traps (with and without hamster bait) and Shannon traps (with lights and horse or human bait), 16 species were collected from seven municipal districts which were known foci for cutaneous leishmaniasis: Arapongas; Apucarana; Cambira; Marumbi; Faxinal; Florestópolis; and Sabáudia. Although the frequency at which each species was collected varied with the collection site, Lutzomyia whitmani predominated (62.0% of all the sandflies collected), followed by Lu. fischeri (13.3%), Lu. pessoai (10.8%), Lu. migonei (8.2%) and Lu. intermedia (2.8%). Lutzomyia monticola, Lu. shanonni, Lu. firmatoi, Lu. lanei, Lu. alphabetica, Lu. misionensis, Lu. correalimai, Lu. cortellezzii, Lu. longipenis, Brumplomyia brumpti and B. nitzulescui together represented the remaining 3.0% of the collected sandflies. Three of the 1961 female sandflies collected and dissected in the municipal district of Cambira, where a recent case of cutaneous leishmaniasis had been registered, were found to have flagellates in their guts. All three were Lu. whitmani. The parasites from each of these infections were successfully isolated in NNN and ‘Tobie and Evans’ media and/or by inoculation into a hind foot of a golden hamster. The results of isoenzyme electrophoresis indicated that all three isolates were of Leishmania (Viannia) braziliensis.

Resistance of gastrointestinal nematodes to anthelmintics in sheep (Ovis aries)

O teste de reducao da contagem de ovos de helmintos por grama de fezes (FECRT) foi usado para testar a eficiencia dos antihelminticos em 42 propriedades produtoras de ovinos, em cinco diferentes regioes no Estado do Parana, Brasil. O estudo foi realizado entre Julho 1996 a Julho de 2000. Foram avaliados animais com infeccao natural. Cinco drogas foram usadas so ou em combinacao (benzimidazole, imidazothiazole, ivermectin, milbemicina e closantel). Resultados mostraram que a prevalencia de resistencia foi alta para todos os antihelminticos avaliados: 88.1% para benzimidazoles (oxfendazole), 78.6% para ivermectin, 56.4% para closantel, 38.7% para closantel + oxfendazole, 38% para levamisole, e 23.6% para moxidectin. Havia resistencia multipla em todas fazendas estudadas. Na identificacao das larvas de helmintos recuperadas das culturas de fezes apos o tratamento verificou-se que maioria pertenciam a Haemonchus sp. e Trichostrongylus sp. O fracasso das drogas existentes no mercado em combater a verminose e considerado um assunto importante. No presente artigo algumas sugestoes sao discutidas para melhorar a situacao, elas incluem uma mudanca de atitude em relacao ao uso indiscriminado de antihelminticos.

Application of the biorefinery concept to produce L-lactic acid from the soybean vinasse at laboratory and pilot scale.

Lactic acid is a product that finds several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work was the development of a bioprocess to produce L(+)-lactic acid using soybean vinasse as substrate. Among ten strains, Lactobacillus agilis LPB 56 was selected for fermentation, due to its ability to metabolize the complex oligosaccharides. Fermentation was conducted without need for supplementary inorganic nitrogen sources or yeast extract. Kinetic and yield parameters determined at laboratory scale were 0.864 and 0.0162 for YP/S and YX/S, 0.0145 g/L h (rx), 1.32 g/L h (rs) and 1.13 g/L h (rp). The use of vinasse enriched with soybean molasses provided higher lactic acid concentration (138 g/L), the best proportion of inoculum being 25% (v/v). After scale-up to a pilot plant, kinetic and yield parameters were 0.849 and 0.0353 for YP/S and YX/S, 0.0278 g/L h (rx), 0.915 g/L h (rs) and 0.863 g/L h (rp).

Lignocellulosic Bioethanol: Current Status and Future Perspectives

Publisher Summary Lignocellulosic biomass is an attractive alternative material for bioethanol fuel production. Lignocellulose is the most abundant renewable resource on Earth, and it constitutes a large component of the wastes originating from municipal, agricultural, forestry, and some industrial sources. The more widespread geographical distribution of lignocellulose sources, compared to fossil reserves, can provide security of supply by using domestic sources of energy. The use of lignocellulosic materials would minimize the conflict between land use for food (and feed) production and energy feedstock production. This raw material is less expensive than conventional agricultural feedstock and can be produced with lower input of fertilizers, pesticides, and energy. Biofuels from lignocellulose generate low net GHG (greenhouse gas) emissions, reducing environmental impact, particularly on climate change. Currently, some countries are producing ethanol from cellulosic feedstock at different development stages, and several public/private international projects have been developed in the biorenewable sector to promote a bio-based economy. Depending on the feedstock considered, its availability for bioethanol production can vary considerably from season to season, and depending on geographic locations, could also pose difficulty in their supply. The changes in the price of feedstocks can highly affect the production costs of bioethanol. Because feedstocks typically account for greater than one third of the production costs, maximizing bioethanol yield would be imperative. Each country must find the best and economical way to use their feedstocks and residues in order to produce biofuels. Brazilian bioethanol program is an example of the efficiency of sugarcane production and high technology bioethanol production.

Milk kefir: composition, microbial cultures, biological activities, and related products

In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir’s exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir’s microflora and the importance of kefiran as a beneficial health substance.

Reorganization and cleanness of peridomiciliar area to control sand flies (Diptera, Psychodidae, Phlebotominae) in South Brazil

The objective of the present work was to evaluate the impact of the reorganization and cleaning of the peridomicily seeking the control of Phlebotominae vectors of Leishmania. Collections of insects were made in domestic animal shelters and in peridomiciliar area located in Jussara farm, Municipality of Jussara, State of Parana, Brazil where cutaneous leishmaniasis has been endemic. The collections were accomplished five nights for month of the 21:00pm for fie hours, in 1996 and 1997. The results were compared the those obtained in the same places in 1992 and 1994. After the collections of 1992 peridomiciliar area was cleaned and organic matter was removed and domestic animals were reallocated. In 1992, 1994 and 1996/97, 10, 7 and 12 Phlebotominae species were observed. Lutzomyia (Nyssomyia) whitmani was predominant species in whole the collection. The total population of phlebotomine in 1992 was 64,725. After the reorganization measures and cleaning the phlebotomine population decrease in 90%. In 1996/97 the environmental conditions retaked the patterns of the beginning of the work and the population increased for 61.51%. The present work demonstrates that the reorganization and cleaning of the peridomicily can take to a decrease in the Phlebotominae population and like this to decrease the risk of transmission of Leishmania in endemic areas.

Survey of giardiosis in household and shelter dogs from metropolitan areas of Curitiba, Paraná state, Southern Brazil.

Giardia duodenalis is a protozoan parasite that causes a broad range of clinical symptoms varying from none--in asymptomatic carriers--to mild recurring diarrhea consisting of soft, light-colored stools to acute severe diarrhea. In different parts of the world this parasite has raised increased interest due to its possible zoonotic transmission. Among domestic animals, dogs can play an important role in environmental contamination. As there is little information on the frequency of giardiosis in dogs from the Metropolitan Area of Curitiba-State of Paraná, Southern Brazil, the aim of the present work was to evaluate the prevalence of G. duodenalis in two dog populations (household and shelter). To attain the proposed aim, we collected fecal samples from 200 dogs and utilized three diagnostic techniques: Fausts technique (Faust et al. 1939), Benbrooks technique (1963) and polymerase chain reaction (PCR). Fausts technique presented the best results, as it was able to detect a larger number of Giardia cases. Taking Fausts technique as the standard, Benbrooks technique presented 66% sensitivity and PCR demonstrated 69% sensitivity. The shelter dog population showed a 24% occurrence of G. duodenalis while the household population showed a 9% occurrence. Other epidemiological aspects like age, sex, environmental conditions and methodological aspects are discussed in the present article.

Teste imunoenzimático (enzyme-linked immunosorbent assay) para diagnóstico da cisitcercose bovina e estudo da cinética de produção de anticorpos contra-Cysticercus bovis

An indirect ELISA (ENZYME-LINKED IMMUNOSORBENT ASSAY) was developed for searching of antibodies against-Cysticercus bovis in bovine. Three antigens were studied: partial antigen of C. cellulosae, total antigen of C. bovis, and total antigen of C. longicollis. In the standardization of the ELISA the following combinations were analyzed: antigen 250 and 500 ng of protein/well, dilution of the sera 50, 100, 200, and 400 times, dilution of the conjugated (anti bovine -IgG conjugated IgG of goat with peroxidase) 400 and 800 times. The crossing of the conditions above resulted in the following standardization: antigen 250 ng/well, sera and conjugated diluted 100 and 400 times respectively. The reaction cut-off between reagents and non-reagents animals was determined by the average of the optic densities of 54 negative sera plus three standard deviation resulting in the value of 0,303. The reactivity of the three antigens used in the ELISA test was compared using sera from experimentally infected calves, using sera dilutions and conjugated standardized previously. Using the antigen of C. bovis was verified high correlation with the test standardized with C. cellulosae. However, the absorbance values were significantly smaller. With C. longicollis was observed low reactivity, but increasing the amount of antigen, up to 3000ng/well, there was a proportional increase of the response. The kinetics of antibodies anti-C. bovis production was studied in ten calves experimentally infected with 2 x 104 T. saginata eggs. Six non-infected calves were used as control. After 90 days from the infection date, the animals were killed. Thirteen samples of sera of each animal were analyzed. The first was picked in the day of the infection and the remaining at each 15 days. The maximum production of antibody was observed between 30 and 60 days post infection. With the standardized test it was detected antibodies against-C. bovis, in 2 from 20 cattle considerated as non-holder of cyst by the inspection service. These animals could be considered possible cyst holders.

Tratamento anaeróbio de esgoto e sua eficiência na redução da viabilidade de ovos de helmintos

This study evaluates the prevalence and viability of helminth eggs and protozoan cysts in sludge obtained by anaerobic treatment in four treatment stations in Curitiba, Parana State, Brazil. The parasites observed were helminths: Ascaris sp (85%), Toxocara sp (5.5%), Trichuris sp (4.5%), Hymenolepis diminuta (3.7%), H. nana (1%) and Taenia sp (0.4%), protozoan: Isospora sp, Entamoeba coli, Entamoeba histolytica, Giardia lamblia, Endolimax nana. In biological treatment based on the anaerobic digestion the effectiveness depends on the duration and temperature. The treatment showed efficiency for pathogen reduction of between 59.7 to 93%. However, the number of helminth eggs found in treatment stations was still high and new higher performance treatment is necessary for land application or for other objectives, seeking to reduce the risks for human and animal health.This study evaluates the prevalence and viability of helminth eggs and protozoan cysts in sludge obtained by anaerobic treatment in four treatment stations in Curitiba, Parana State, Brazil. The parasites observed were helminths: Ascaris sp (85%), Toxocara sp (5.5%), Trichuris sp (4.5%), Hymenolepis diminuta (3.7%), H. nana (1%) and Taenia sp (0.4%), protozoan: Isospora sp, Entamoeba coli, Entamoeba histolytica, Giardia lamblia, Endolimax nana. In biological treatment based on the anaerobic digestion the effectiveness depends on the duration and temperature. The treatment showed efficiency for pathogen reduction of between 59.7 to 93%. However, the number of helminth eggs found in treatment stations was still high and new higher performance treatment is necessary for land application or for other objectives, seeking to reduce the risks for human and animal health.This study evaluates the prevalence and viability of helminth eggs and protozoan cysts in sludge obtained by anaerobic treatment in four treatment stations in Curitiba, Parana State, Brazil. The parasites observed were helminths: Ascaris sp (85%), Toxocara sp (5.5%), Trichuris sp (4.5%), Hymenolepis diminuta (3.7%), H. nana (1%) and Taenia sp (0.4%), protozoan: Isospora sp, Entamoeba coli, Entamoeba histolytica, Giardia lamblia, Endolimax nana. In biological treatment based on the anaerobic digestion the effectiveness depends on the duration and temperature. The treatment showed efficiency for pathogen reduction of between 59.7 to 93%. However, the number of helminth eggs found in treatment stations was still high and new higher performance treatment is necessary for land application or for other objectives, seeking to reduce the risks for human and animal health.