Growth conditions of clostridium perfringens type B for production of toxins used to obtain veterinary vaccines.

The diseases caused for Clostridium perfringens are generically called enterotoxemias because toxins produced in the intestine may be absorbed into the general circulation. C. perfringens type B, grown in batch fermentation, produced toxins used to obtain veterinary vaccines. Glucose in concentrations of 1.4-111.1 mM was used to define the culture medium. The minimum concentration for a satisfactory production of vaccines against clostridial diseases was 55.6 mM. Best results were brought forth by meat and casein peptones, both in the concentration 5.0 g l(-1) in combination with glucose and a culture pH maintained at 6.5 throughout the fermentation process. The production of lactic, acetic and propionic organic acids was observed. Ethanol was the metabolite produced in the highest concentration when cultures maintained steady pH of 6.5 with exception of cultures with initial glucose concentration of 1.4 mM, where the highest production was of propionic acid. Maximal cell concentration and the highest toxin title concomitantly low yield coefficient to organic acids and ethanol were obtained using basal medium containing 111.1 mM glucose under a controlled pH culture (pH) 6.5 in batch fermentations of C. perfringens type B. These data contribute to improve process for industrial toxin production allowing better condition to produce a toxoid vaccine.

Atividade antimicrobiana de extratos hidroalcoolicos das folhas de alecrim- pimenta, aroeira, barbatimão, erva baleeira e do farelo da casca de pequi / Antimicrobial activity of hydroalcoholic extracts from rosemary, peppertree, barbatimão and erva baleeira leaves and from pequi peel meal

Avaliou-se o perfil fitoquímico de extratos hidroalcoólicos padrão (EAPs), obtidos a partir das folhas de alecrim-pimenta (Lippia sidoides), aroeira (Myracrodruon urundeuva), barbatimão (Stryphnodendron adstringens), erva baleeira (Cordia verbenacea) e do farelo da casca do fruto do pequi (Caryocar brasiliense) e a atividade antimicrobiana de diferentes concentrações desses EAPs contra Staphylococcus aureus e Escherichia coli. Após coleta e identificação, as folhas das plantas e cascas do pequi foram usadas para preparação dos EAPs e submetidas a rastreamento fitoquímico. A atividade antimicrobiana dos EAPs em diferentes diluições (200, 300, 400 e 500mg mL-1) foi testada pela técnica de difusão em ágar. O rastreamento fitoquímico detectou componentes com potencial antimicrobiano em todos os EAPs. Nos testes de difusão em ágar, os extratos de aroeira (≥200mg mL-1), barbatimão (≥300mg mL-1) e erva-baleeira (≥400mg mL-1) inibiram o crescimento de S. aureus, mas não de E. coli. Os EAPs não mostraram atividade sobre E.coli, todavia as folhas de aroeira, barbatimão e erva-baleeira evidenciaram potencial para inibir o crescimento de S. aureus. O uso das folhas e cascas dessas espécies vegetais pode constituir-se numa alternativa sustentável, viável e acessível para tratamento antimicrobiano.

This study evaluated the phytochemical profile of standardized hydroalcoholic extracts (EAPs) obtained from leafs of rosemary (Lippia sidoides), peppertree (Myracrodruon urundeuva), barbatimão (Stryphnodendron adstringens), erva baleeira (Cordia verbenacea) and from the meal of pequi fruit peel (Caryocar brasiliense) and the activity of different levels of these EAPs against Staphylococcus aureus and Escherichia coli. After collection and identification of the species, plant leaves and pequi peel were separated to prepare the EAPs. The EAPs underwent phytochemical screening. The antimicrobial activity of the EAPs at different dilutions (200, 300, 400 and 500mg mL-1) was tested using the disk diffusion method. The phytochemical screening detected components with antimicrobial potential in the EAPs tested. The disk diffusion test showed that peppertree (≥200mg mL-1), barbatimão (≥300mg mL-1) and erva-baleeira (≥400mg mL-1) extracts inhibited S. aureus growth, but not E. coli development. The EAPs did not affect E. coli development, but the leaves from peppertree, barbatimão and erva-baleeira exhibited potential to inhibit S. aureus growth. The leaves and bark of the studied plants may consist in a sustainable, affordable and feasible alternative to treat microbial infections.