Streptococcus infantarius Endophthalmitis after XEN Gel Stent Implantation

Purpose: To report a case of Streptococcus infantarius endophthalmitis related to the use of a XEN® Gel Stent.Case summary: A 75-year-old male was referred to our practice with a diagnosis of endophthalmitis 55 days after XEN® Gel Stent implantation. He had primary open-angle glaucoma. Visual acuity was 20/50. Slit-lamp examination revealed conjunctival injection and anterior chamber inflammation with hypopyon. Fundus examination showed inflammatory cells with exudative materials in the vitreous. The aqueous sampling for culture of causative micro-organisms was followed by removal of the XEN® Gel Stent, along with anterior chamber irrigation and intracameral and intravitreal injection of antibiotics. Streptococcus infantarius was isolated after 5 days. Vitrectomy, anterior chamber lavage, and intravitreal injection of antibiotics were additionally performed to control the intraocular inflammation. Sixteen days after vitrectomy, the intraocular inflammation disappeared. The choroidal detachment was resolved 34 days after vitrectomy. Visual improvement was limited to 20/100 at 6 months.Conclusions: XEN® Gel Stent-related bacterial endophthalmitis was successfully treated by implant removal, vitrectomy, and proper intraocular antibiotic treatment.

The Functionality of African Streptococcus Thermophillus and Streptococcus Infantarius Sub Sp. Infantarius in Milk Fermentation

Fermentation serves a key role in inhibiting spoilage microorganism through acidification and production of antimicrobial compounds. The technological information on properties of Streptococcus infantarius sub sp. infantarius which is predominant in most African fermented is dairy products very little. This study was therefore carried out to determine the functionality of selected African Streptococci strains in fermented dairy products. Pasteurized milk samples from camels and cows were inoculated with different strains and a selected combination at a rate of 3% v/v and incubated at different temperatures of 25 oC, 30 oC, 37 oC, and 45 oC for 9 hours. Analysis was done after every 3 hours for pH and titratable acidity while viscosity was done after incubation and cooling of the product. The different fermented milk samples were subsequently evaluated for consumer acceptability. Milk inoculated with both African type Streptococcus thermophillus (146A8.2) and Streptococcus infantarius sub sp. infantarius CJ 18 (9377), and incubated for nine hours recorded the highest amount of titratable acidity of 0.97 for the camel milk and had the least pH value of 4.12 for cow milk compared to the other strains. The cow milk had the highest viscosity level of 59.64 cPs compared to camel milk which was 29.44 cPs. The levels of titratable acidity and viscosity depended on the strain and incubation temperature. The African type Streptococcus thermophillus (146A8.2) and Streptococcus infantarius sub sp. infantarius CJ 18 (9377), isolated from fermented camel milk had good technological properties that are useful as starter culture for development of fermented milk products.

Streptococcus infantarius 25124 isolated from pozol produces a high molecular weight amylopullulanase, a key enzyme for niche colonization

Pozol is a beverage made with maize dough that is prepared after boiling the kernels in limewater, causing a decrease in soluble sugars, with starch being the main fermentable carbohydrate in the dough. Previously, Streptococcus infantarius ssp. infantarius 25124 (Sii-25124) was identified as the most amylolytic bacteria isolated in this product. Analysis of Sii-25124 amylolytic enzymes revealed two amylases, a cytoplasmic α-amylase of 55.7 kDa and an extracellular amylopullulanase of 246.3 kDa, with two catalytic domains, one typical of an α-amylase and another typical of a pullulanase/glycogen debranching enzyme. Characterization of the joint activity of both enzymes using Sii-25124 cell lysate supernatant demonstrated stability between 30 °C and 45°C, and pH stability in a range between 6.8 and 8.0. The joint activity of Sii-25124 amylases showed a fast production of reducing sugars when starch was used as the substrate. In contrast, reducing sugar production from amylopectin was lower, but it steadily increased throughout the reaction time. The amylopullulanase produced by Sii-25124 hydrolyzes the starch in the dough to produce low molecular weight oligosaccharides, which may be transported into Sii-25124 cells, so that intracellular α-amylase hydrolyzes them to mono- and disaccharides. Amylopullulanase production by Sii-25124 could be an example of a specialized enzyme that successfully dominates starchy food fermentation.

Atividade antagonista in vitro de bactérias ácido láticas isoladas de queijo de coalho artesanal do Sertão paraibano frente a microrganismos indicadores

Bactérias ácido láticas (BAL) produzem substâncias inibitórias de patógenos e deteriorantes de alimentos e isso tem despertado interesse sobre seu uso na preservação e na segurança sanitária desses produtos. Assim, o estudo foi realizado com o objetivo de avaliar a atividade inibitória de Streptococcus infantarius subsp. infantarius isoladas de queijo de coalho artesanal do Sertão da Paraíba frente a microrganismos indicadores. A avaliação do potencial antagônico foi realizada pela técnica de difusão em disco frente à estirpe reveladora Escherichia coli, isolada das mesmas amostras de queijos e frente ao patógeno de referência Escherichia coli ATCC 3539. Das 11 estirpes analisadas, 81,8% foram capazes de inibir o microrganismo indicador isolado dos mesmos queijos de coalho, enquanto 36,4% das bactérias láticas apresentaram inibição frente ao patógeno de referência. Conclui-se que as cepas Streptococcus infantarius subsp. infantarius isoladas de queijos de coalho do Sertão da Paraíba apresentam potencial antagônico e podem assegurar a qualidade microbiológica de alimentos fermentados, inclusive o queijo de coalho.

Bactérias ácido láticas isoladas de queijo de Coalho do nordeste brasileiro na produção de laticínios: Uma triagem para aplicação tecnológica

No Brasil, a produção laticínios é o segundo segmento mais importante da indústria de alimentos, devido as suas características nutricionais e sensoriais. As culturas lácticas são empregadas na tecnologia de produção para acentuar o sabor, aroma, textura e acidez dos laticínios que os tornam mais aceitáveis pelos consumidores. Portanto, o objetivo desse estudo foi avaliar o potencial tecnológico de espécies do gênero Enterococcus e cepas de Streptococcus infantarius subsp. infantarius isoladas de queijo de Coalho artesanal da Paraíba, Brasil, a fim de selecioná-las para a fabricação de produtos lácteos fermentados. Foram avaliados a capacidade acidificante, atividade proteolítica, produção de aroma, atividade de β-Galactosidase, tolerância ao cloreto de sódio e atividade antagonista contra diferentes patógenos. Das cepas analisadas, 26,67% foram consideradas rápidas acidificantes, 33,33% foram capazes de produzir enzimas proteolíticas, 26,67% apresentaram atividade enzimática de β-galactosidase e 33,33% foram tolerantes ao cloreto de sódio. Os patógenos formam inibidos por 40,00% das bactérias ácido láticas (BAL) testadas. As cepas de Enterococcus apresentaram valores mais elevados do que as cepas de S. infantarius subsp. infantarius, em especial a cepa Enterococcus faecium KT990027. Assim podemos concluir que E. faecium KT990027 pode ser usada como cultura iniciadora, pois apresentou as melhores características tecnológicas gerais aplicáveis a este tipo de cultura. Esses resultados confirmam que o queijo de Coalho artesanal da Paraíba possui BAL que podem ser utilizadas na indústria de laticínios.