Isolation and Characterization of Pigment-Producing Yeasts from Various Natural Sources and Assessment of Their Antimicrobial Activity

Abstract

This study explores the isolation and characterization of pigment-producing yeasts from diverse natural sources and evaluates their antimicrobial properties. Pigment-producing yeasts are increasingly significant in biotechnology and industry due to their natural pigments, which serve as eco-friendly alternatives to synthetic colorants. Samples were collected from various ecological niches, followed by the isolation of yeast strains. The characterization process involved morphological, physiological, and molecular techniques to identify strains capable of pigment production. The antimicrobial activity of these yeast isolates was assessed against several pathogenic microorganisms. Samples were obtained from soil, fruit surfaces, and leaves across different geographical locations. Yeast strains were isolated using standard microbiological methods and cultured on selective media to promote yeast colony growth. Pigment-producing colonies were identified based on visual coloration. Characterization included microscopic examination, physiological tests assessing growth under varying conditions, and molecular identification using DNA sequencing, particularly the ITS region. Results indicated that a subset of isolated yeasts demonstrated notable pigment production. The pigments were extracted, and their chemical properties analyzed, with evaluations of pigment yield and stability under different environmental conditions. Additionally, the antimicrobial activity of these pigment-producing yeasts was tested against common bacterial pathogens, including Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Several yeast strains exhibited significant antimicrobial effects, effectively inhibiting pathogen growth. The dual benefits of pigment production and antimicrobial activity in these yeasts suggest promising applications in food preservation, pharmaceuticals, and as natural colorants in various industries. This study underscores the potential of pigment-producing yeasts in offering sustainable and non-toxic alternatives to synthetic colorants, along with added antimicrobial benefits. Future research should focus on optimizing pigment extraction and scaling up production processes for industrial applications.