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Key research themes
1. How can molecular and phenotypic techniques improve the accuracy and speed of yeast species identification in clinical and industrial settings?
This theme investigates the efficacy and optimization of various molecular, biochemical, and culture-based methods for the reliable identification of yeast species, especially in clinical diagnostics and biotechnological processes. Accurate species identification is critical for targeted antifungal treatment, detection of mixed infections, and quality control in fermentation, as different yeast species can differ significantly in pathogenicity, drug resistance, and technological traits.
Key finding: Combining chromogenic medium subculture with MALDI-TOF MS yielded a yeast species identification turnaround time under 0.35 days with 98.79% isolates identified on the first or second MALDI-TOF attempt, and detected mixed... Read more
Key finding: The 21-plex PCR assay accurately identified 87.3% of yeast isolates, outperforming API 20C AUX (83.7%) and achieving 100% identification of key Candida species; combining 21-plex PCR and API 20C AUX raised correct... Read more
Key finding: Expanding the MALDI Biotyper database with 143 locally relevant yeast strains improved identification accuracy to near 100% for 388 regional clinical yeast isolates across 55 species, highlighting the importance of database... Read more
Key finding: API 20 C microtube biochemical tests correctly identified 95% of 300 clinical yeast isolates compared to 98.7% by conventional methods, showing good agreement in carbohydrate fermentation and assimilation tests. While useful... Read more
Key finding: While conventional phenotypic methods remain common in clinical yeast diagnosis, molecular techniques like DNA sequencing have significantly improved sensitivity and specificity, enabling reliable differentiation of Candida... Read more
2. What is the ecological diversity and biotechnological potential of yeast species isolated from natural, food, and industrial environments?
This theme explores the discovery, molecular identification, and characterization of yeast strains from diverse environments such as marine ecosystems, fermented food matrices, forest soils, and bio-waste residues. Insights include the taxonomic diversity present, adaptation to environmental stresses, biochemical profiles relevant for biotechnology (e.g., lipid content, enzyme activities), and utilization as starter cultures or single cell proteins/oils. Understanding these characteristics enhances strain selection for industrial applications like bioethanol production, food fermentation, and oleochemical synthesis.
Key finding: Five marine yeast strains were identified molecularly (ITS1 and D1/D2 sequencing) as species including Yarrowia lipolytica and Candida tenuis, exhibiting protein content up to 40%, essential amino acids up to 64% of total... Read more
Key finding: Identification of nine yeast species from 433 isolates across fermented doughs and cereal matrices revealed species diversity with low intra-dough but high inter-dough variation. Phenotypic assessments identified strains with... Read more
Key finding: From 127 yeast strains isolated from mountain forest soils, 78 strains representing 10 species accumulated cellular lipids exceeding 20% of dry biomass, including two species (Papiliotrema terrestris and P. flavescens) newly... Read more
Key finding: Molecular techniques (PCR-RFLP and MSP-PCR) identified diverse yeast genera including Debaryomyces, Yarrowia, and Candida in Turkish cheeses. Isolates exhibited proteolytic, lipolytic, and antagonistic activities (e.g.,... Read more
3. What is the clinical and environmental distribution of opportunistic and pathogenic yeast species, and how does this impact infection risk and diagnosis?
This research area focuses on identifying pathogenic yeast species beyond clinical settings, understanding their environmental reservoirs, assessing their role in infections, and improving detection in clinical samples. It addresses the rising clinical importance of non-albicans Candida and other novel yeasts, their antifungal resistance profiles, and the implications for infection management. This theme underscores the complexity of yeast ecology in natural carriers and fomites, which affects disease epidemiology and diagnostic accuracy.
Key finding: Fifty-four opportunistic pathogenic yeast strains, including Candida albicans, C. glabrata, and Pichia kudriavzevii, were isolated from approximately 1,000 diverse U.S. environmental samples such as fruits and soil,... Read more
Key finding: Molecular identification of 202 clinical yeast strains revealed 121 non-albicans Candida (NAC) species and uncommon yeasts like Trichosporon asahii and Pichia terricola; P. terricola was first reported as a urinary pathogen... Read more
Key finding: Among 176 yeast isolates predominantly from Candida genus, DNA sequencing identified species with higher accuracy (99.4%) than MALDI-TOF MS (89%). Most isolates were resistant to azole antifungals, especially non-albicans... Read more
Key finding: The study verified the non-cytotoxic nature of isolated marine yeasts on human embryonic kidney (HEK 293) cells, indicating potential safety for biotechnological applications and suggesting that environmental yeast isolates... Read more