Barbosa Jr. A.M.,Federal University of Minas Gerais |
Barbosa Jr. A.M.,Laboratorio Of Microbiologia Aplicada Lma |
De Oliveira Santos B.F.,Federal University of São Paulo |
De Oliveira Carvalho E.,Cardiology |
And 4 more authors.
Jornal Brasileiro de Patologia e Medicina Laboratorial | Year: 2013
Introduction: Cryptococcus neoformans and Cryptococcus gattii are encapsulated basidiomycetous yeasts with worldwide distribution. They cause cryptococcosis with features of systemic infection, affecting the central nervous system, lungs and skin in humans and animals. These fungi present numerous virulence factors that allow them to invade the host and multiply, among which extracellular enzyme capacity and microbial adaptation to different temperatures are worth mentioning. Objective: To evaluate the production of protease and investigate possible differences in thermotolerance and urease activity in clinical and environmental yeast isolates. Material and methods: Culture methods and Pz analysis were applied to assess urease and protease, whereas the optical density method was used to analyze biological activity in thermotolerance. Results: There was no significant results as to microbial growth at the tested temperatures (25°, 37° and 42°C). It was observed that clinical specimens grew better than environmental ones at elevated temperatures. As to C. neoformans, the moderate production of urease enzyme prevailed in both clinical and environmental isolates within 24h or 48h. Moreover, there was significant production on the seventh day of reading. The best reading time for viewing protease production in both isolates and species was the seventh day: 96% clinical samples and 94% environmental isolates. Conclusion: Further studies are required in order to investigate the virulence factors of C. neoformans and C. gattii cerebrospinal isolates from patients with meningoencephalitis and environmental samples from Sergipe. Furthermore, a higher technical accuracy and statistical precision are indispensable.
Gola D.,Applied Microbiology Laboratory |
Dey P.,Applied Microbiology Laboratory |
Bhattacharya A.,Applied Microbiology Laboratory |
Mishra A.,Applied Microbiology Laboratory |
And 3 more authors.
Bioresource Technology | Year: 2016
Towards the development of a potential remediation technology for multiple heavy metals [Zn(II), Cu(II), Cd(II), Cr(VI) and Ni(II)] from contaminated water, present study examined the growth kinetics and heavy metal removal ability of Beauveria bassiana in individual and multi metals. The specific growth rate of B. bassiana varied from 0.025 h−1 to 0.039 h−1 in presence of individual/multi heavy metals. FTIR analysis indicated the involvement of different surface functional groups in biosorption of different metals, while cellular changes in fungus was reflected by various microscopic (SEM, AFM and TEM) analysis. TEM studies proved removal of heavy metals via sorption and accumulation processes, whereas AFM studies revealed increase in cell surface roughness in fungal cells exposed to heavy metals. Present study delivers first report on the mechanism of bioremediation of heavy metals when present individually as well as multi metal mixture by entomopathogenic fungi. © 2016 Elsevier Ltd