Coccidioidomycosis in Latin America

Coccidioidomycosis is a highly prevalent systemic mycosis in Latin America and has been reported (human and zoonotic cases) in México, Guatemala, Honduras, Colombia, Venezuela, Brazil, Paraguay, Bolivia, and Argentina. The incidence of coccidioidomycosis in Latin America is unknown due to lack of clinical awareness and limited access to laboratory diagnosis. Coccidioidomycosis is as prevalent in Mexico as in the endemic regions of the United States. The number of cases reported in Brazil and Argentina has progressively increased during the last decade, including areas that were not considered as endemic. Genetic studies have shown that the prevalent species in Latin America is Coccidioides posadasii. Coccidioides immitis has been reported sporadically in indigenous cases from Mexico and Colombia. Coccidioidomycosis and tuberculosis share some risk factors such as immunosuppression and residing in areas endemic for these conditions, so their coexistence in the same patient is not uncommon in Latin America. In most regions, clinical diagnosis of coccidioidomycosis is based on direct sputum examination and histopathology results from biopsies or autopsies. This would explain why primary coccidioidomycosis is rarely diagnosed, and most cases published are about chronic pulmonary or disseminated disease

Emulsifying Activity and Stability of a Non-Toxic Bioemulsifier Synthesized by Microbacterium sp MC3B-10

A previously reported bacterial bioemulsifier, here termed microbactan, was further analyzed to characterize its lipid component, molecular weight, ionic character and toxicity, along with its bioemulsifying potential for hydrophobic substrates at a range of temperatures, salinities and pH values. Analyses showed that microbactan is a high molecular weight (700 kDa), non-ionic molecule. Gas chromatography of the lipid fraction revealed the presence of palmitic, stearic, and oleic acids; thus microbactan may be considered a glycolipoprotein. Microbactan emulsified aromatic hydrocarbons and oils to various extents; the highest emulsification index was recorded against motor oil (96%). The stability of the microbactan-motor oil emulsion model reached its highest level (94%) at 50 degrees C, pH 10 and 3.5% NaCl content. It was not toxic to Artemia salina nauplii. Microbactan is, therefore, a non-toxic and non-ionic bioemulsifier of high molecular weight with affinity for a range of oily substrates. Comparative phylogenetic assessment of the 16S rDNA gene of Microbacterium sp. MC3B-10 with genes derived from other marine Microbacterium species suggested that this genus is well represented in coastal zones. The chemical nature and stability of the bioemulsifier suggest its potential application in bioremediation of marine environments and in cosmetics