The Lipase Activities of Malassezia Species Isolated from Seborrhoeic Dermatitis/Dandruff Patients DC17-DC19
Dr. Shivaprakash M Rudramurthy,
Professor, Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research,
Introduction: Malassezia a commensal yeast, can become pathogenic leading to different clinical forms of dermatosis. Being an obligatory lipophilic, the lipolytic enzymes produced by them help in their growth by obtaining useful lipids from the environment further contributing to the pathogenesis of dermatosis. There are no comparative reports concerning secreted lipase activities of Malassezia species associated with Seborrhoeic Dermatitis/Dandruff (SD/D).
Aim: To analyse and compare lipase activities of Malassezia spp. isolated from SD/D patientâ€™s lesional area and Healthy Controls (HC) and correlates this feature in pathogenesis of SD/D.
Materials and Methods: Lipase activities of Malassezia species isolated from lesional area of SD/D patients and HC were analysed and compared. Extracellular proteins of Malassezia spp. were extracted from the Leeming and Notman agar after removing and weighing the yeast cells from the agar surface. The lipase activity was measured using an assay based on hydrolysis of p-Nitrophenylpalmitate (pNPP). ANOVA test and GraphPad were used for statistical analysis.
Results: Malassezia furfur wet fungal weight was higher (1.1Â±0.13 g) compared to M. globosa (0.36Â±0.4 g) and M. restricta (0.26Â±0.4 g). The mean extracellular lipase activity of M. globosa (0.15 U) and M. restricta (0.18 U) was significantly higher than M. furfur (0.08 U) isolates (p<0.001). No significant difference was observed among M. globosa (SD/D-0.15 U vs. HC-0.14 U), M. restricta (SD/D-0.2 U vs. HC-0.16 U) and M. furfur (SD/D-0.08 U vs. HC-0.1 U) isolated from SD/D patientâ€™s lesional area and HC.
Conclusion: The lipase activity of M. globosa and M. restricta was higher despite slow growth rate. Lipase activity alone may not play a role in the onset of SD/D. As the pathogenic mechanism of fungi is complex, it is difficult to explain the pathogenicity of Malassezia based only on lipase activities.