STUDY OF MICROBIAL PIGMENTS AS ANTIDANDRUFF AGENTS

Dandruff is common problem affecting human beings and thus hair care industries are focusing on development of antidandruff agents. Malassezia species, lipophilic yeasts are the main causative agents of dandruff. Currently Zinc pyrithione, Ketoconazole are widely used as antidandruff agents. As there is an increase in demand towards the use of the natural antimicrobial agents, microorganisms can be one such source to be tapped. Microorganisms produce pigments which have antimicrobial property and can be assessed for antidandruff activity. The current study focusses on isolation of pigment producing bacteria from soil and water samples from different ecological niche. Pigments were extracted from the pigment producing organisms. The pigments were screened for their antimicrobial activity against Malassezia sp. and Candida albicans which are dandruff causing organisms. The pigments showed effective antimicrobial property in control of dandruff causing organisms and can be further used as antidandruff agents in shampoo or cream.

Clinico epidemiological and mycological study of pityriasis versicolor PITYRIASIS VERSICOLOR

Background: Pityriasis versicolor, a chronic superficial fungal infection caused by lipophilic yeasts of the genus, Malassezia is a common infection in the tropical and subtropical regions. Objective was to study the epidemiology, clinical presentation, associations, etiological agents and clinico-mycological correlation of pityriasis versicolor. Methods: Hundred patients with clinical diagnosis of pityriasis versicolor who attended the mycology out-patient (OP) clinic between September 2014 and August 2015 were enrolled. Skin scrapings from these patients were subjected to 10% potassium hydroxide (KOH) and culture.Results: Out of the 100 patients with pityriasis versicolor (PV), 70% were males and 30% were females and the most affected age group was between 21-30 years (43%). The youngest age affected was a 13 years old male while the oldest was a 65 years old male. Duration of the infection ranged between 1 month to 6 months in 65% while it was more than 1 year in 9% of patients. Recurrence was observed in 35% of them. Back was the most common site (48%) to be involved. Seventy percent of patients had more than 30% body surface area involvement. Achromic type of PV was the most common clinical presentation in 68% of patients. Out of the 76 isolates, Malassezia globosa was the predominant isolate (48.7%), followed by M. sympodialis (25%), M. furfur (10.5%), M. restricta (7.9%) and M. obtusa (6.6%).Conclusions: Achromic type of PV is the most common clinical presentation. Malassezia globosa is the most common etiological agent of pityriasis versicolor.

Occurrence of Malassezia Yeasts in Dermatologically Diseased Dogs

The Malassezia genus is represented by several lipophilic yeasts, normally present on the skin of many warm-blooded vertebrates, including humans. The aim of this study was to investigate the occurrence of Malassezia yeasts in dogs with skin lesions (dermatitis, interdigital dermatitis and inflammation of anal sacs) and otitis externa. The presence of Malassezia spp. was investigated in a group of 300 dogs exhibiting clinical manifestations. The isolates of Malassezia were identified by using phenotypic (biochemical-physiological and morphological characteristics) and genotypic methods (PCR, RFLP-AluI, BanI and MspA1I) which allowed their precise identification. Malassezia yeasts were isolated from 84 specimens obtained from 76 positive dogs. M. pachydermatis was the most frequently isolated species (79 isolates) in this study. M. furfur was identified in four dogs and M. nana in one dog. The prevalence of isolated Malassezia spp. was 25.3 % in dogs with skin lesions; from which 36.0 % were dogs suffering from otitis externa, 24.5 % from dogs having dermatitis, 16.4 % from dogs with interdigital dermatitis and 14.3 % from dogs having inflammation of the anal sacs. A higher prevalence of Malassezia spp. was observed in animals with pendulous ears in comparison with dogs having erect ears.

Isolation of Malassezia species from healthy cats and cats with otitis

Lipid-dependent Malassezia species have recently been cultured from veterinary specimens. The identification of Malassezia species isolates from animals is important to clarify the epidemiology of these lipophilic yeasts. Malassezia species were cultured from the external ear canals of 63 out of 99 cats with otitis and 12 of 52 (23%) healthy control cats. The rate of isolation in affected animals versus controls was highly significant ( P<0.01). Malassezia pachydermatis was isolated as a pure culture in 33 (45.2%) cats, associated with Malassezia globosa and Malassezia furfur in 20 (50%) and 17 (42.5%) animals, respectively. Three different species were isolated simultaneously in three cats (two cats with M pachydermatis, M globosa and M furfur, one subject with M pachydermatis, M furfur and Malassezia sympodialis). M globosa was isolated as the sole species in two animals. The present work confirms the presence of some lipid-dependent species of Malassezia in both healthy and otitic cats.