Ana Maria Queijeiro López

Evaluation of sugar-cane vinasse treated with Pleurotus sajor-caju utilizing aquatic organisms as toxicological indicators

Toxicity tests with aquatic organisms constitute an effective tool in the evaluation, prediction and detection of the potential effect of pollutants from environmental samples in living organisms. Vinasse, a highly colored effluent, is a sub-product rich in nutrients, mainly organic matter, with high pollutant potential when disposed in the environment. Assays for vinasse decolorization were performed using the fungus Pleurotus sajor-caju CCB020 in vinasse biodegradation study, were occurred reductions of 82.8% in COD, 75.3% in BOD, 99.2% in the coloration and 99.7% in turbidity. The vinasse toxicity reduction was determined by the exposition to the following organisms: Pseudokirchneriella subcapitata, Daphnia magna, Daphnia similis and Hydra attenuata. This work concluded that the systematic combination of P. sajor-caju and vinasse can be applied in the bioprocess of color reduction and degradation of complex vinasse compounds, with reduction in the toxicity and improving its physical-chemical properties.

Influence of seasonality on the chemical composition of oysters (Crassostrea rhizophorae).

This paper aimed to evaluate the influence of seasonality on the chemical composition of oysters (Crassostrea rhizophorae). Samples were collected during summer and winter from the estuary and lagoon complex of the municipality of Barra de São Miguel, Alagoas, Brazil. Statistical differences (p<0.05) between summer and winter were observed in relation to chemical composition. The oysters cultivated in the winter presented some nutritional advantages because of the higher levels of proteins and functional nutrients, such as the eicosapentaenoic-docosahexaenoic acid combination and percentages of polyunsaturated fatty acids (n-3 and n-6), and the lower levels of saturated fatty acids. Therefore, the animals in winter presented a higher content of cholesterol oxides. The levels of cholesterol oxides found in these products during winter may encourage researchers to investigate the composition of oysters cultivated in different climates all over the world.

Composition and antioxidant activity of honey from Africanized and stingless bees in Alagoas (Brazil): a multivariate analysis

Summary The purpose of this study was to evaluate the antioxidant activity of honey from different entomological sources which were harvested in the dry season of 2008–2009 from distinct mesoregions of the State of Alagoas in the North East of Brazil. Honey produced by five different species of bees, even from the same region and season, showed a statistically significant difference (p <0.05) in the content of phenols, flavonoids and antioxidants, with higher levels of these compounds found in honey produced by Plebeia spp. and A. mellifera. Honey from stingless bees was quite different from that of A. mellifera, especially from the Plebeia spp. A dendrogram of the five species of bees showed the formation of 3 groups, one being formed by Apis mellifera, one by the genus Melipona (M. subnitida, M. quadrifasciata and M. scutellaria and another formed by Plebeia spp.

Colletotrichum isolates related to Anthracnose of cashew trees in Brazil: morphological and molecular description using LSU rDNA sequences

Thirty six isolates of fungi obtained from anthracnose lesions of cashew and associated host plants in Brazil, were compared by their cultural, morphological and partial sequences of the 28S ribosomal DNA characters. They showed a high degree of cultural variability. The average mycelial growth rate on all tested media ranged from 10.2-13.3 mm/day between the isolates. Most of them produced perithecia (sterile and fertile) and some produced setae (sterile and fertile). All the isolates produced acervuli with predominantly cylindrical conidia (12.4-17.7 µmX 4.8-6.0 µm in width) with round ends, which became septate on germination, and produced unlobed or slightlylobed appressoria. Comparison of the D2 domain of the large subunit (LSU) rDNA sequences with those of other defined species of Colletotrichum and Glomerella grouped 35 of the isolates with known strains of C. gloeosporioides from different hosts (> 98.9% homology). The one exception (LARS 921) was identical to G. cingulata (LARS 238) from Vigna unguiculata.

Microfiltração do soro de leite de búfala utilizando membranas cerâmicas como alternativa ao processo de pasteurização

The purpose of this work was to evaluate the efficiency of a ceramic membrane with (porosity of 0.8 µm) to filter the whey of buffalos milk aiming to reduce the microbial charge and characterize the nutritional value of this product. The results were compared with those of the pasteurization process (65 oC, 30 minutes). Seven assays were carried out by submitting the samples to filtration or pasteurization processes. The samples were then analyzed before (SBF) and after (SAF) filtration and after pasteurization (SAP) regarding the mesophyllic aerobic bacteria count. The milk whey samples before filtration (SBF) was also characterized regarding physico-chemical parameters (pH, density, acidity, humidity, total dried extract, concentration of total fats, lactose, and protein). The results indicate a reduction of the microbial charge from 4.04 x log CFU.mL-1 to 1.50 x log CFU.mL-1 in the SAP samples and to 0.70 x log CFU.mL-1 in the SAF samples. Other findings were pH = 6.29, acidity = 10.07, humidity = 89.94, total dried extract = 10.06, density = 1.029, protein = 1.19%, lactose = 5.85%, and fat = 1.37%. The microfiltration process using a ceramic membrane proved more efficient than the pasteurization process regarding microbial charge reduction.

Total carotenoids and antioxidant activity of fillets and shells (in natura or cooked) of “Vila Franca” shrimp (Litopenaeus Schmitti) in different intervals of storage under freezing

Shrimps are sources of carotenoids, astaxanthin is the predominant, responsible for their special and desirable properties, as well as for their instability under heat treatment during the domestic preparation, industrial processing or storage under freezing. These can cause discoloration and reduce the beneficial health properties. This study aimed to evaluate the effect of heat treatment and storage under freezing (0, 45 and 90 days) on the levels of total carotenoids and stability of the antioxidant activity of ethanolic extracts of fillets and shells, raw and cooked, of the white shrimp (“Vila Franca”) Litopenaeus schmitti (Burkenroad, 1938). The antioxidant ability of the extracts was evaluated using the radicals DPPH• (2,2-diphenyl-1-picryl-hydrazyl) and ABTS+• (2,2’-azino-bis (3-ethylbenzothiazoline-6 sulfonic acid), as well as by the iron reducing power (FRAP) test. The extracts of cooked or in natura shrimps (fillets and shells) represent dietary sources of carotenoids, displaying antioxidant activity through all the tested methods, after heat treatment and storage under freezing. The antioxidant activity of the extracts was superior to the one of ascorbic acid, mainly in the cooked fillet and shells. The samples of shrimp shells seemed a valuable source of carotenoids, whose antioxidant activity was verified even 90 days after freezing, and can be used in food products as functional natural supplement, adding value to this waste.

SELEÇÃO POLIFÁSICA DE MICRORGANISMOS PRODUTORES DE POLIHIDROXIALCANOATOS

Polyhydroxyalkanoates (PHAs) are fully biodegradable biopolyesters produced by many prokaryotes and accumulated as insoluble cytoplasmatic inclusions. The detection of these intracellular granule is usually provided using lipofilic azodyes, which are not specific. Another way to screen PHA-producing bacteria is through culture-independent molecular techniques such Polymerase Chain Reaction (PCR), and the search for new PHA-producer strains is essential to reduce the cost at industrial level. The application of these both methods is desirable. In the present study, 24 bacteria isolated from soil of the Atlantic forest in Maceio (AL, Brazil) and from agri-industrial sludge (Coruripe-AL, Brazil) were studied regarding to their capacity of growing in mineral salt medium, as indicative of PHA synthesis. All strains were submitted to biochemical characterization, whilst PCR has proved that isolates BMA-05, BMA-10, BMA-13 and BDL-07 has the gene phaC, which encodes a PHA synthase, the key for PHA synthesis. The amplification and sequencing of their 16S r-DNA region was able to identify these bacteria respectively as Pseudomonas fluorescens, Enterobacter aerogenes, Klebsiella oxytoca and Bacillus pumilus. The same minimal medium supplement with peptone demonstrated to induce growing of those strains.

Reaction of dwarf cashew clones to Colletotrichum gloeosporioides isolates in controlled environment

A cultura de caju (Anacardium occidentale L.) e uma fonte de renda importante para a populacao do Nordeste brasileiro, sendo a antracnose causada por Colletotrichum gloeosporioides a doenca que mais conduz a perdas de sua producao. Entretanto, ha pouca informacao para a resistencia desse hospedeiro ou para a variacao na agressividade do patogeno em ambiente controlado. A reacao de clones comerciais (CCP-06, CCP-09, CCP-76 e CCP-1001) e um nao comercial (CAP-14) de cajueiros anao-precoce, contra 36 isolados desse fungo, foi avaliada sob condicoes controladas. Todos os isolados, incluindo os provenientes de diferentes hospedeiros, foram capazes de causar lesoes sobre folhas e hastes da maioria dos clones, ainda que em graus diferenciados. O clone CCP-06 foi o mais suscetivel, enquanto o clone CCP-1001 foi resistente a mais isolados, incluindo o 905, enquanto os isolados 910 e 912 foram agressivos a todos os clones testados. A injuria mecânica das folhas aumentou a suscetibilidade dos clones a todos os isolados, indicando que a resistencia pode tambem estar associada a barreiras estruturais que impedem a penetracao. Os pseudofrutos amadurecidos (8 semanas) dos clones comerciais avaliados, foram suscetiveis a ambos os isolados testados (905 e 910), mas os jovens (2 semanas), com excecao daqueles do clone CCP-76, suscetiveis aos dois isolados, apresentaram resistencia a ambos, sugerindo a acao de obstaculos estruturais e quimicos diferenciados. As castanhas desenvolvidas (8 semanas), no entanto, foram mais resistentes a ambos os isolados do que as jovens (2 semanas), talvez devido a espessa cuticula do exocarpo e baixo numero de estomatos.

THE FUNGAL ABILITY FOR BIOBLEACHING/BIOPULPING/BIOREMEDIATION OF LIGNIN-LIKE COMPOUNDS OF AGRO-INDUSTRIAL RAW MATERIAL

Lignin is present in plant cell secondary wall, associated to carbohydrates preventing their efficient hydrolysis, and cellulose pulp manufacture basically consists in breaking down the middle lamella of plant cells, individualizing fibers such as cellulose from the other biopolymers. Different levels of lignocellulose are found in plant residues and they can be decomposed by extracellular fungal lignin modifying enzymes, used as a tool to reduce waste materials in contaminated soils and effluents. In the paper mill industries, for instance, they are a suitable or complementary alternative to the traditional methods of pulping/bleaching, contributing to improve paper strength as well as to reduce the pitch content, the quantity of chemicals and the consume of electrical energy. The aim of this review was to describe the fungal degradation of lignocellulosic like-material, the non-specific enzymatic aspects of the attack of wood and agricultural wastes, the fungal ability for biosorption and bioconversion, and its applications in the pulp/paper industry and bioremediation.

Physicochemical composition and antioxidant potential of bee pollen from different botanical sources in Alagoas, Brazil

Bee pollen results from the mixture of pollen and floral nectar with the salivary substances of bees and has increasingly been used as a food with therapeutic properties. In this study, 30 samples of bee pollen from Apis mellifera apiaries in three mesoregions of Alagoas (Brazil) Mata Atlântica, South Coast and Caatinga, were collected during the dry season of 2008/09 and analysed. Mata Atlântica and Caatinga had good production of bee pollen. In the same season, Mata Atlântica contained a higher diversity of pollen types for feeding bees with a predominance of herbaceous pollen (63%), whereas the Caatinga samples contained monofloral pollen. Physicochemical data were analysed with the nonparametric Kruskal-Wallis statistical test. The Caatinga samples were analysed to determine their contents of total phenolic compounds (25.85 ± 10.80 mg gallic acid eq/g) and flavonoids (45.62 ± 32.19 mg quercetin eq/g) and their antioxidant activity (for instance, 70.62 ± 4.50% in the DPPH test), which were possibly affected by the environmental conditions of this biome.