Effects of cumulative doses of vinasse on soil microorganisms in cerrado

Counts of colony forming units of actinomycetes, bacteria and filamentous fungi were determined in cerrado soil treated with vinasse (processed sugar cane effluent) for 5 yr, using doses of 20 l m-2a-1 and 50 l m-2a-1. A temporary increase in the counts of actinomycetes and bacteria for some months after the addition of vinasse was observed. An increased number of fungi was detected throughout the experiment together with qualitative changes in the population. The most abundant fungi in cerrado soil not treated with vinasse (control soil) were Chaetomium, yeasts, Mucor, Penicillium and Trichoderma, while in vinasse treated soils, the same genera adding Verticillium, with the exception of yeasts, were the most common fungi. -Author

Factors determining rock phosphate solubilization by microorganisms isolated from soil

Forty two soil isolates (31 bacteria and 11 fungi) were studied for their ability to solubilize rock phosphate and calcium phosphate in culture medium. Eight bacteria and 8 fungi possessed solubilizing ability. Pseudomonas cepacia and Penicillium purpurogenum showed the highest activity. There was a correlation between final pH value and titratable acidity (r = - 0.29 to -0.87) and between titratable acidity and soluble phosphate (r = 0.22 to 0.99). Correlation values were functions of insoluble phosphate and of the group of microorganisms considered. A high correlation was observed between final pH and soluble phosphate only for the rock phosphates inoculated with the highest concentration of solubilizing bacteria (r = -0.73 to -0.98).

Produção de biomassa por fungos Filamentosos em meio de vinhaça de cana-de-açúcar suplementado com melaço

Three species of filamentous fungi, Aspergillus niger, Penicillium fellutanum and Mucor hiemalis, were selected and cultivated in vinasse media with different addition of molasses, pasteurized to 85°C for 30 minutes and with pH = 5.0. The microorganisms, previously adapted to the respective medium for 48 hours, from a solution of 107 spores.ml-1, were cultivated in pure and mixed cultures in Erlenmeyer vessel of 500ml, to 30°C, with constant agitation of 170 rpm, for 24, 48 and 72 hours, with four repetition for each samples. The biomass was separated by vacuum filtration in filter Whatman #1 and dried in oven at 105°C until right weight, the obtained liquid was submited to COD analysis. The datas were statistically analysed using a response surface methodology, to improve the effect on the molasses proportion and culture time, in the biomass production by microorganism in research. According to the obtained results (5.02% of molasses, 55.59h, 70% of spores solution of A. niger and 30% of spores solution of P. fellutanum), cultivating was carried out in Microferm Fermentor New Brunswick for 48 hours at 300 rpm, aired at 1v/v/m, using 5 liters of medium added with 5.0% of molasses on the conditions above described. The average of the results obtained (6.81g.l-1) was higher than the confidence interval (5.937 ; 6.369) and was inside the prediction interval (4.471 ; 7.834) both of them significant at 95% by the statistical test employed.

Fungus incidence on peanut grains as affected by drying method and Ca nutrition

An experiment was conducted to study the effects of liming and drying method on Ca nutrition, fungus infection and aflatoxin production potential on peanut (Arachis hypogea) grains. Peanut cv. Botutatu was grown in the absence or presence of liming to raise the base saturation of the soil from 20 to 56%. Calcium contents of the soil were increased from 5.5 to 14.6 mmol((c))kg-1 and pH from 4.2 to 4.9. After harvest, plants and pods were dried in (1) shade, (2) field down to 100 g water kg-1 (3) field down to 250 g water kg-1 and transferred to a forced-air oven at 30°C, (4) field down to 360 g water kg-1 and transferred to a forced-air oven at 30°C. Calcium contents were analyzed in the grains, pericarps and seed coats. The incidence of Aspergillus spp., Penicillium spp., Rhizopus spp. and potential aflatoxin production in vitro were evaluated, as well as the seed coat thickness. The seed coat was thicker when peanut was grown in the presence of lime, leading to a decrease in seed infection by Aspergillus spp. and Penicillium spp. When plants were dried in shade, the growth of aflatoxinogenic fungi was independent of liming. However, in plants dried in the field or field + oven, the development of these fungi was decreased and even suppressed when the Ca content of the seed coat was increased from 2.2 to 5.5 g kg-1.

Influence of different drying temperatures on the amount of essential oils and citral content in Cymbopogon citratus (DC) Stapf. - Poaceae

Studies were conducted to show the effect of different temperatures in the drying process on the amount and quality of essential oils of Cymbopogon citratus (DC) Stapf. Leaves were harvested in the experimental field of the Agronomical Sciences College, UNESP, Botucatu, SP, Brazil in September, 1996. Blades of the leaves were cut in small parts (about 1-1,5 cm length), dried for several days at 30°, 50°, 70° and 90°C, until establishment of the weights. In the following process a hydrodistillation, during 2.5 hours, by Clevenger apparatus, was subsidized to extract the essential oils. A higher amount of oil could clearly be collected with the lower drying temperatures, except at 30°C, affected by fungus growing. Aspergillus sp., Penicillium sp., Rhyzopus sp., Cladosporium sp., Trichoderma sp. and Alternaria sp. were observed in the leaves. The analysis of the oil by GC-MS showed the variation of citral concentration of the treatments (86,1 to 95,2%). The results proved it is worthwhile to spend more time and effort in the production process using longer times of careful drying.

Microbiota fúngica de um prédio com laboratórios da região de Araraquara-SP

From September 2000 to January 2001, airborne fungi were isolated from the building of the Clinical Analyses laboratories, including its didactic and research rooms, in Araraquara São Paulo State, Brazil, by using Andersen, MAS-100® (MERCK) machine, with Sabouraud chloramphenicol medium. After 5 days of incubation at 25°C, the colonies of the fungi were counted, resulting in the identification of 21 taxa. Cladophialophora spp. was the most isolated in internal and external environments as well, followed by Penicillium spp. and Mycelia spp. In accordance with the resolution n° 9, January 2003 (ANVISA), fungi considered unacceptable were found in nine internal environments and one of these presented the amount of fungi above of the acceptable limit. Among the obtained fungi, at least 16 taxa were reported as opportunistic, nine were related to plant diseases and seven were associated to allergy problems.

Aspectos físico-químicos e microbianos do queijo maturado por mofo obtido da coagulação mista com leite de cabra congelado e coalhada congelada

Milk goats are indicated as an economic alternative for small farmers and cheese making could improve their profits. Goat's milk has a seasonal production characteristic and shows periods of abundance and others of scarcity. The use of frozen milk or frozen curd to make cheese can be used to solve the problem. The aim of this work was to evaluate the preparation of cheese made from mixed curd and ripened by Penicillium candidum mould using slow frozen milk (in a domestic freezer) or fast frozen milk (by liquid nitrogen). The slow frozen curd and fast frozen curd without whey were used. It was observed that the cheese from the slow and fast frozen milk and from the slow and fast frozen curd did not differ from the control cheese for the yield, chemicophysical characteristics, chemical composition, extention ripened rate, depth ripened rate and microbiological aspects, even when it was expressed as a dry matter content of cheeses.

Qualidade fisiológica e sanitária de sementes de feijoeiro (Phaseolus vulgaris L.) provenientes do estado de Goiás

The common beans (Phaseolus vulgaris L.) is a fabacea sufficiently spread out in all domestic territory. However, the quality of its seeds represents one of the main causes of low productivity in the beans farmings in Brazil. The objective of this work was to evaluate physiological and sanitary seed qualities of eleven bean cultivars. The physiological seed quality was evaluated trough standard germination and vigor tests. The sanitary seed quality was evaluated through two tests: blotter test was employed to evaluate fungi incidence and Koch & Menten method was employed to observe Sclerotinia sclerotiorum (Lib) de Bary occurrence. Xamego, BRS Valente, Bambu and Pérola had the best results of physiological tests. Jalo Precoce, Roxo 90, Corrente and Aporé had no good results of vigor and germination, besides presenting the lowest indices of died seeds. Fusarium sp., Aspergillus spp., Penicillium sp., Phoma sp., Rhizopus sp. and Botrytis sp. were the fungi detected in the sanity tests.

Patulina: Incidência e controle em derivados de maçã

The patulin, (4hydroxy-4furo[3,2-c]pyran(6H)-1), is a thermal resistent mycotoxin produced by several species of fungi are common in plants, mainly in derivatives and apples. Studies on the toxicity in animals have shown that mycotoxin has character teratogenic, and carcinogenic in mice immunotoxic. Its biosynthesis is well understood involving a series of reactions of condensation and oxiredução, many catalyzed by enzymes. The danger of contamination of food with patulin, warning about the need for a more rigorous control. Recent research aimed their removal and degradation as well as increase the sensitivity of the tests, making them faster and at less cost. The removal of patulin of food is made with composite adsorbents, with inconvenience to diminish the quality of the product by adsorbs other components desirable. The degradation is made with sulfur compounds, which are not allowed in food in many countries, and the growth of yeasts, such as the production of cider. Many yeasts have resistance against patulin and produce compounds capable degrade it. Here, we reviewed research on patulin with emphasis on its influence in food industry, incidence of patulin in apple juice and other foods, maximum permissible concentrations, health effects, biosynthesis, removal, degradation and most widely used methods for its detection and quantification.

Qualidade fisiológica e sanitária de sementes de mamona submetidas a diferentes tratamentos químicos

The use of fungicides for treating seeds has become an essential measure in the control of pathogens. However, the effectiveness of many products is not well-known to some crops. The objective of this research was to evaluate the effect of different doses of carbendazin and carboxin + thiram fungicides for controlling pathogens and their interference on the physiologic quality of castor bean seeds. The test consisted of the following treatments (g i.a./100 kg of seeds): carbendazin (15, 30, and 60), carboxin + thiram (25 + 25, 50 + 50, and 100 + 100), formol 0.15% (v/v), and control (distilled water). The physiologic quality of the seeds was determined by germination, first counting, field emergence, speed emergence index, length, fresh and dry weight of the aerial part, and electrical conductivity. There were no statistical differences for germination and fresh and dry matter index. The treatment with formol provided lower values for first counting and field emergence. Seeds treated with fungicides presented higher values for electrical conductivity, but did not differ, statistically, among themselves. The fungi Cladosporium spp.; Bipolaris spp.; Curvularia spp.; Aspergillus flavus; Aspergillus niger; Rhizopus sp.; Penicillium sp.; Rhizoctonia sp.; Verticillium sp.; Fusarium sp.;Arthrobotrys sp.; and Epicocum sp. were identified. All tested products, independently of the dose, provided efficient control for pathogens.

Efeito do tratamento químico na sanidade de sementes de espécies florestais

This study evaluated the effect of different fungicide and sodium hypochlorite treatments in reducing the incidence of fungi on seeds of native species of the Atlantic rainforest. The experiment was done using the completely randomized design in a 5×5 factorial with five levels of factor A (forest species) and five levels of factor B (chemical treatment and surface disinfection with sodium hypochlorite) with four replications. The fungal genera Fusarium, Alternaria, Aspergillus and Penicillium were identified. The species 'Jacarandáda- Bahia' and 'Ipê-roxo' had lower fungal incidence, 1.0% and 1.3%, respectively. Except for 'Angico Vermelho', the fungicide pencycurom and sodium hypochlorite were not significantly different from the control in the species evaluated. Seed treatment with fungicides 'Captan' and 'Tiram' yielded satisfactory results in reducing the incidence of fungal contamination in forest species seeds.

Estudo da mcrobiota fúngica gastrintestinal de morcegos (Mammalia, Chiroptera) da região noroeste do estado de São Paulo: Potencial zoonótico

Bats are hosts of a rich diversity of microorganisms. Many studies indicate a close link between bats and fungi with pathogenic potential, especially for living in environments such as caves, caverns and hollow trees, favorable to the maintenance and spread of fungi. The objective was to study the gastrointestinal mycoflora of bats. Of the 98 samples belonging to 11 species of bats coming from 15 studied cities, 20% of the species were Carollia perspicillata, 19% Artibeus lituratus, 17% Molossus rufus, 13% Glossophaga soricina, 9% Nyctinomops macrotis, 8% Molossus molossus, 7% Desmodus rotundus, 2% Lasiurus ega and 1% Eptesicus furinalis, Myotis nigricans and Tadarida brasiliensis. The genus Aspergillus sp. was isolated from 29% of the samples, followed by 6% Microsporum sp. and Penicillium sp. 4% Trichophyton sp. and zygomycetes and 2% Fusarium sp. Of yeast species, 14% were from Rhodotorula sp., 10% Candida sp. and 2% Cryptococcus sp., 22% of isolates remained unidentified. All 82 cultures of organs were negative for Histoplasma capsulatum. There was a statistically significant association between the results of microbiological culture and bat species (p < 0.05). We conclude that the bats can act as disperser agents of fungi with pathogenic potential, although other studies should be performed to establish strategies to identify the main factors correlated with the growth and spread of microorganisms in nature and implication of bats in the epidemiological cycle.

Filamentous fungi from the Atlantic marine sponge Dragmacidon reticulatum

Dragmacidon reticulatum is a marine sponge of wide occurrence in the Eastern and Western Atlantic. Little is known about D. reticulatum fungal diversity. Filamentous fungi recovered from D. reticulatum were assessed in the present study using a polyphasic taxonomic approach, including classical morphology, molecular biology and MALDI-TOF ICMS. Ninety-eight fungal strains were isolated from two D. reticulatum samples by using six different culture media, which were identified up to the genus level. Sixty-four distinct fungal ribotypes were obtained, distributed among twenty-four different genera belonging to the Ascomycota and Zygomycota. Representatives of Penicillium and Trichoderma were the most diverse and abundant fungi isolated. Amongst Penicillium spp. three isolates belonged to the same ribotype can be considered as a putative new species. Data derived from the present study highlight the importance of using a polyphasic approach to get an accurate identification in order to structure a reliable culture collection. © 2012 Springer-Verlag Berlin Heidelberg.

Xylo-oligosaccharides from lignocellulosic materials: Chemical structure, health benefits and production by chemical and enzymatic hydrolysis

Currently, there is worldwide interest in the technological use of agro-industrial residues as a renewable source of food and biofuels. Lignocellulosic materials (LCMs) are a rich source of cellulose and hemicellulose. Hemicellulose is rich in xylan, a polysaccharide used to develop technology for producing alcohol, xylose, xylitol and xylo-oligosaccharides (XOSs). The XOSs are unusual oligosaccharides whose main constituent is xylose linked by β 1-4 bonds. The XOS applications described in this paper highlight that they are considered soluble dietary fibers that have prebiotic activity, favoring the improvement of bowel functions and immune function and having antimicrobial and other health benefits. These effects open a new perspective on potential applications for animal production and human consumption. The raw materials that are rich in hemicellulose include sugar cane bagasse, corncobs, rice husks, olive pits, barley straw, tobacco stalk, cotton stalk, sunflower stalk and wheat straw. The XOS-yielding treatments that have been studied include acid hydrolysis, alkaline hydrolysis, auto-hydrolysis and enzymatic hydrolysis, but the breaking of bonds present in these compounds is relatively difficult and costly, thus limiting the production of XOS. To obviate this limitation, a thorough evaluation of the most convenient methods and the opportunities for innovation in this area is needed. Another challenge is the screening and taxonomy of microorganisms that produce the xylanolytic complex and enzymes and reaction mechanisms involved. Among the standing out microorganisms involved in lignocellulose degradation are Trichoderma harzianum, Cellulosimicrobium cellulans, Penicillium janczewskii, Penicillium echinulatu, Trichoderma reesei and Aspergillus awamori. The enzyme complex predominantly comprises endoxylanase and enzymes that remove hemicellulose side groups such as the acetyl group. The complex has low β-xylosidase activities because β-xylosidase stimulates the production of xylose instead of XOS; xylose, in turn, inhibits the enzymes that produce XOS. The enzymatic conversion of xylan in XOS is the preferred route for the food industries because of problems associated with chemical technologies (e.g., acid hydrolysis) due to the release of toxic and undesired products, such as furfural. The improvement of the bioprocess for XOS production and its benefits for several applications are discussed in this study. © 2012 Elsevier Ltd.

Fungal communities in the garden chamber soils of leaf-cutting ants

Leaf-cutting ants modify the properties of the soil adjacent to their nests. Here, we examined whether such an ant-altered environment impacts the belowground fungal communities. Fungal diversity and community structure of soil from the fungus garden chambers of Atta sexdens rubropilosa and Atta bisphaerica, two widespread leaf-cutting ants in Brazil, were determined and compared with non-nest soils. Culture-dependent methods revealed similar species richness but different community compositions between both types of soils. Penicillium janthinellum and Trichoderma spirale were the prevalent isolates in fungus chamber soils and non-nest soils, respectively. In contrast to cultivation methods, analyses of clone libraries based on the internal transcribed spacer (ITS) region indicated that richness of operational taxonomic units significantly differed between soils of the fungus chamber and non-nest soils. FastUnifrac analyses based on ITS sequences further revealed a clear distinction in the community structure between both types of soils. Plectania milleri and an uncultured Clavariaceae fungus were prevalent in fungus chamber soils and non-nest soils, respectively. FastUnifrac analyses also revealed that fungal community structures of soil from the garden chambers markedly differed among ant species. Our findings suggest that leaf-cutting ants affect fungal communities in the soil from the fungus chamber in comparison to non-nest soils. © 2013 WILEY-VCH Verlag GmbH & Co.