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A thiol-yne click chemistry approach was adopted for the first time to prepare highly water-soluble bile acid derived dicationic amphiphiles. The synthesized amphiphiles dicationic cysteamine conjugated cholic acid (DCaC), dicationic cysteamine conjugated deoxycholic acid (DCaDC), and dicationic cysteamine conjugated lithocholic acid (DCaLC) exhibited hierarchically self-assembled microstructures at various concentrations in an aqueous medium. Interestingly at below critical micellar concentration (CMC) the amphiphiles showed distinct fractal patterns such as fractal grass, microdendrites and fern leaf like fractals for DCaC, DCaDC and DCaLC respectively. The fractal dimension (Df) analysis indicated that the formation of fractal like aggregates is a diffusion limited aggregation (DLA) process. The preliminary aggregation studies such as determination of CMC, fluorescence quenching, wettability and contact angle measurements were elaborately investigated. The morphology of the aggregates were analyzed by SEM and OPM techniques. Further, we demonstrated the antimicrobial and hemolytic activity for the cationic amphiphiles. DCaC had potent antimicrobial activity and showed no toxicity on human RBCs indicating that DCaC could be used in biomedical applications, in addition to their industrial and laboratory applications such as detergency, surface cleaning, and disinfection agent.

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is a common species isolated both from clinical specimens and the environment. Human infections caused by C. guilliermondii are uncommon particularly in immunocompetent individuals. 1 Molecular typing methods have helped to characterize the strains of C. guilliermondii into different groups, one of which has been named as Candida fermentati. 2 This species includes organisms phenotypically similar to C. guilliermondii but with minimal nucleotide divergence in the D1/D2 domains of 26S rDNA. 3 This is the first report of the isolation of C. fermentati from the oral cavities of HIV patients.C. fermentati was isolated from five HIV patients, four of whom had oral lesions, while one was asymptomatic. Only one patient had a CD4 cell count below 50 cells/mm 3 (Table 1). The isolates were initially speciated by sugar fermentation and assimilation tests. Susceptibility to azole antifungals fluconazole and itraconazole was tested by determination of minimum inhibitory concentrations (MIC) using the agar dilution method according to Troke and Pye. 4 The isolates resembled C. guilliermondii by sugar fermentation and assimilation tests, but differed from C. guilliermondii in their inability to assimilate glycerol. They were confirmed to be C. fermentati by Dr Wieland Meyer, University of Sydney at the Westmead Millennium Institute, Australia, by PCR fingerprinting, and the primer used was 5 0 GAGGGTGGCGGTTCT 3 0 from the core sequences of wild type phage M13. 5 All the five isolates showed PCR fingerprint-