Abstract This study aimed to make and characterize a fresh cheese using the surplus of bovine colostrum from dairy farms. The bovine colostrum was characterized in terms of fat (4.00%), protein (16.30%), moisture (79.68%), ash (0.95%), minerals, pH (6.32), titratable acidity (0.27 g/100 mL), immunoglobulin G (>50 g/L), lactose (1.60%), color, and the presence of pathogenic bacteria. The fresh cheese made with colostrum was characterized in the same terms as the bovine colostrum (fat (7.00%), protein (22.95%), moisture (67.98%), ash (1.85%), minerals, pH (6.15), titratable acidity (0.04 g/100 mL), immunoglobulin G (30.95 g/L), lactose (not detectable), color, and the presence of pathogenic bacteria), with the addition of the texture and sensory analysis. The colostrum cheese had high moisture content (67.98%) and low-fat content (7.00%). The protein content was also high (22.95%), whose major percentage was composed by immunoglobulins. An important finding in this work was associated with the possible absence of lactose in the colostrum cheese, thus opening opportunities for future research regarding the development of dairy products for lactose intolerant consumers. In addition, the high concentration of immunoglobulin G might give this product an immune boost feature. The sensorial analysis showed that the recipe of the fresh cheese requires improvement to achieve higher acceptance from the public, especially regarding texture.

Resumo Este trabalho teve como objetivo a elaboração e caracterização de um queijo fresco a partir do excedente de colostro bovino de fazendas leiteiras. O colostro foi caracterizado quanto aos teores de gordura (4,00%), proteínas (16,30%), umidade (79,68%), cinzas (0,95%), minerais, pH (6,32), acidez titulável (0,27 g/100 mL), imunoglobulina G (>50 g/L), lactose (1,60%), cor e presença de bactérias patogênicas. O queijo fresco elaborado com colostro foi submetido às mesmas caracterizações do colostro: gordura (7,00%), proteínas (22,95%), umidade (67,98%), cinzas (1,85%), minerais, pH (6,15), acidez titulável (0,04 g/100 mL), imunoglobulina G (30,95 g/L), lactose (não detectável), cor e presença de bactérias patogênicas, além da avaliação dos parâmetros de textura e da análise sensorial. O queijo fresco elaborado com colostro apresentou alto teor de umidade (67,98%) e baixo teor de gordura (7,00%). A porcentagem de proteína foi elevada (22,95%), sendo grande parte composta por imunoglobulinas. O teor de lactose do queijo fresco elaborado com colostro foi muito baixo para ser quantificado, indicando a possibilidade de desenvolvimento de novos produtos lácteos a partir de colostro para consumidores intolerantes à lactose. Além disso, o queijo apresentou elevada concentração de imunoglobulina G, que pode conferir a esse produto a propriedade de reforço imunológico. A análise sensorial mostrou que o processo de elaboração do queijo fresco com colostro deve ser aprimorado para aumentar a aceitação dos consumidores, principalmente no que se refere à textura.

Abstract We investigated the immobilization of a tetrameric Kluyveromyces lactis β-galactosidase (EC: 3.2.1.23) (KL-Gal) on Immobead 150 using different support modification strategies. Immobead support was modified using an acid solution of H2SO4:HNO3 (3:1) (Immobead-Ac) or 5 % (v/v) glutaraldehyde (Immobead-Glu). Its unmodified form (Immobead) was also tested. Immobilization yields and efficiencies were evaluated by testing protein loads from 10 to 200 mg.g-1 support. The thermal, physico-chemical, textural and catalytic properties of the supports (modified and unmodified) and their derivatives (Immobead-KL-Gal, Immobead-Ac-KL-Gal and Immobead-Glu-KL-Gal) were analyzed. The highest immobilization yields and efficiencies were achieved with a protein load of 100 mg.g-1 support. Surface and pore areas of the Immobead support were greatly decreased after modification. Michaelis constant of the immobilized β-galactosidase increased in the derivatives. Maximum velocity decreased approximately 2.8 times for Immobead-KL-Gal and Immobead-Glu-KL-Gal, and approximately 1.4 times for Immobead-Ac-KL-Gal. In batch processes, the three derivatives could be reused successfully at least 15 times, maintaining high residual enzymatic activity during the lactose hydrolysis (in both cheese whey and milk). The tetrameric K. lactis β-galactosidase immobilized on Immobead supports via the tested treatments was stabilized and is an alternative tool for lactose hydrolysis in the dairy industry.

Toxoplasma gondii é um protozoário parasita que infecta animais de sangue quente, incluindo seres humanos. Pequenos roedores e marsupiais têm papel importante na epidemiologia do T. gondii, pois são fontes de infecção para os felídeos domésticos e selvagens. Amostras de soro de 151 roedores e 48 marsupiais, capturados na Mata Atlântica, Estado de São Paulo, Sudeste do Brasil, foram analisadas para a pesquisa de anticorpos anti-T. gondii. Os anticorpos foram detectados pelo Teste de Aglutinação Modificada (MAT ≥ 25), com 8,6% (13/151) dos roedores e 10,4% (5/48) dos marsupiais soropositivos, com títulos variando de 25 a 6.400 e de 25 a 3.200, respectivamente, para os roedores e os marsupiais. Três das oito espécies de roedores (Akodon spp., Oligoryzomys nigripes e Rattus norvegicus) e uma das quatro espécies de marsupiais (Didelphis aurita) apresentaram animais positivos. A presença de anticorpos anti-T. gondii foi descrita pela primeira vez no roedor Oligoryzomys nigripes.

Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and marsupials play an important role in the epidemiology of T. gondii because they are sources of infection for domestic and feral cats. Serum samples from 151 rodents and 48 marsupials, captured in the Atlantic Forest, São Paulo State, southeastern Brazil, were analyzed for the presence of T. gondii antibodies. Antibodies detected by the modified agglutination test (MAT ≥ 25) were found in 8.6% (13/151) of the rodents and 10.4% (5/48) of the marsupials, with titers ranging from 25 to 6400 and from 25 to 3200, respectively for the rodents and marsupials. Three of the eight species of rodents (Akodon spp., Oligoryzomys nigripesand Rattus norvegicus), and one from the four marsupial species (Didelphis aurita) presented positive animals. T. gondii was described for the first time in the rodent Oligoryzomys nigripes.

Foram avaliados 304 cães de ambiente rural e urbano do município de Monte Negro, Rondônia, através do Antígeno Acidificado Tamponado (AAT), Soroaglutinação Lenta em Tubos (SAL) e 2-Mercaptoetanol (2-ME) para a pesquisa de anticorpos anti-Brucella abortus e da Imunodifusão em gel de ágar (IDGA) e Imunodifusão em gel de ágar com soro tratado com 2-Mercaptoetanol (IDGA-ME) para Brucella canis. Foram consideradas positivas as amostras reagentes nas provas confirmatórias do 2-ME e IDGA-ME. Verificaram-se 56 (18,4%) animais reagentes ao AAT e 12 (4,0%) reagentes a SAL. Apenas um cão (0,3%) foi considerado positivo, confirmado pela prova do 2-ME. Foram observadas 11 (3,6%) reações á IDGA, porém não houve confirmação na prova do IDGA-ME. Ressalta-se a baixa ocorrência de cães positivos ao 2-ME e a ausência de animais reagentes á IDGA-ME.

Serum samples from 304 dogs living in urban or rural areas of Monte Negro County, Rondônia State, Brazil, were evaluated for Brucella abortus reactivity using the Rose-Bengal Test (RBT), Standard Tube agglutination Test (SAT), and Mercaptoethanol Test (MET), and for Brucella canis reactivity using the Immunodiffusion test (AGID) and Immunodiffusion test with 2-Mercaptoethanol (ME-AGID). Serum was considered positive if reacted in the MET or ME-AGID. Fifty-six (18.4%) dogs reacted by the RBT, and 12 (4.0%) by the SAT. One (0.3%) dog was positive by the MET. Eleven (3.6%) dogs reacted by the AGID, but with no confirmation by the ME-AGID. It the small occurrence of dogs reacting by the MET and the absence of reactivity by ME-AGID is emphasized.