Resumo
The identification of mitochondrial DNA polymorphisms is one of the most efficient methods for species differentiation. Genotyping of molecular markers using PCR/RFLP is a reliable, sensitive and inexpensive method for the detection of species specific mutations. The major causes of decline in Sirenia populations are accidental and intentional catches, collisions with boats and habitat loss. The goal of the present study was to identify, in silico, nucleotide mutations in the cytochrome b gene that can be used for the future development of forensic tools capable of using small tissue fragments to discriminate manatee meat from domesticated species meat commonly used as food sources (bovine, ovine, caprine and swine). DNA sequence alignments revealed two polymorphic sites distinguishing the manatee species from domestic species. The present study reinforced the power of cytochrome polymorphisms as powerful markers for species identification, which may be particularly useful for identifying vulnerable/endangered species. The data provided herein also suggest such mtDNA markers as important conservation tools for combating predatory manatee hunting for illegal meat trade in the Americas
Resumo
The identification of mitochondrial DNA polymorphisms is one of the most efficient methods for species differentiation. Genotyping of molecular markers using PCR/RFLP is a reliable, sensitive and inexpensive method for the detection of species specific mutations. The major causes of decline in Sirenia populations are accidental and intentional catches, collisions with boats and habitat loss. The goal of the present study was to identify, in silico, nucleotide mutations in the cytochrome b gene that can be used for the future development of forensic tools capable of using small tissue fragments to discriminate manatee meat from domesticated species meat commonly used as food sources (bovine, ovine, caprine and swine). DNA sequence alignments revealed two polymorphic sites distinguishing the manatee species from domestic species. The present study reinforced the power of cytochrome polymorphisms as powerful markers for species identification, which may be particularly useful for identifying vulnerable/endangered species. The data provided herein also suggest such mtDNA markers as important conservation tools for combating predatory manatee hunting for illegal meat trade in the Americas
Resumo
The identification of mitochondrial DNA polymorphisms is one of the most efficient methods for species differentiation. Genotyping of molecular markers using PCR/RFLP is a reliable, sensitive and inexpensive method for the detection of species specific mutations. The major causes of decline in Sirenia populations are accidental and intentional catches, collisions with boats and habitat loss. The goal of the present study was to identify, in silico, nucleotide mutations in the cytochrome b gene that can be used for the future development of forensic tools capable of using small tissue fragments to discriminate manatee meat from domesticated species meat commonly used as food sources (bovine, ovine, caprine and swine). DNA sequence alignments revealed two polymorphic sites distinguishing the manatee species from domestic species. The present study reinforced the power of cytochrome polymorphisms as powerful markers for species identification, which may be particularly useful for identifying vulnerable/endangered species. The data provided herein also suggest such mtDNA markers as important conservation tools for combating predatory manatee hunting for illegal meat trade in the Americas
Resumo
A sobrevivência de bactérias probióticas durante o trânsito no trato gastrointestinal é fundamental, e implica na capacidade de sobrevivência dos microrganismos à acidez do estômago e a bile para que elas possam exercer os seus efeitos benéficos sobre o hospedeiro. O objetivo deste estudo foi avaliar, "in vitro", cepas de Lactobacillus originadas de material fecal de crianças de um ano de idade para o processo de seleção de microrganismos probióticos. Linhagens comerciais de L. casei (Lc 01TM) e L. acidophilus (La-05 TM) foram utilizadas como controle. A primeira triagem resultou no isolamento de 75 colônias provenientes de seis amostras de fezes. Os isolados foram apresentados como Gram positivos, principalmente bacilos (cocobacilos, bacilos longos e finos), e raramente cocos. Estes foram submetidos a testes de catalase e avaliados quanto à presença de esporos, resultando em 30 amostras pré-selecionadas. Entre estas cepas, oito linhagens: L4, L5, L12, L19, L20, L22, L23, L24 foram as mais resistentes à inibição por Oxgall. Estas oito cepas foram também resistentes às condições ácidas (pH 3,0) e todas as cepas foram capazes de crescer na presença de fenol. Os resultados dos tratamentos foram comparados através do teste Student Neuman Keuls a 5% de probabilidade, com análises de regressão feitas em diferentes tempos, para verificar a tolerância às condições do trato intestinal.
The probiotic bacteria survival during the gastrointestinal transit is primordial, and implies in the ability of microorganisms to survive at the stomach acidity and bile, so they can exert their beneficial effects on the host. The aim of this study was to evaluate, in vitro, Lactobacillus strains originated from one year old children fecal material in the selection of probiotic microorganisms. Two commercial strains, L. casei (Lc 01TM) and L. acidophilus (La-05 TM) were used as controls. The first screening resulted in 75 colonies and they were isolated from six samples faeces. Isolates were Gram positive, mostly rod shaped (cocobacilli, long and thin rods) and rarely cocci. They were submitted to catalase test and evaluated for the presence of spores, resulting in 30 pre-selected strains. Among those strains, eight strains: L4, L5, L12, L19, L20, L22, L23, L24 were the most resistant to Oxgall (bile salts) concentration (0.3 w/v). These eight strains were also resistant to acid conditions (pH 3.0) and all strains were able to grow in the presence of 0.3 w/v of phenol. The results of treatments were compared to the Neuman Keuls Student test at 5% of probability, with regression analyses made at different times for tolerance to intestinal conditions. The results demonstrated that all these strains were able to survive under gastrointestinal stress condition, indicating potent