Genetic diversity of Saccharomyces cerevisiae isolated from different feed sources: applications and implications for biotechnological animal health

Background Saccharomyces cerevisiae strains were isolated from various sources and studied due to their significant potential as probiotics for treating different diseases. They act as adjuvants against gastrointestinal tract disorders, including bowel disease and various types of diarrhea in humans and animals. Consequently, identifying different strains of S. cerevisiae and confirming their safe consumption by humans and animals became crucial. Objective This study aims to isolate, identify, and characterize 36 S. cerevisiae isolates from different animal feed sources. The primary goal is to examine the diversity among these isolates. Materials and methods Yeast isolation from feed involved using Rose Bengal agar, which was incubated at a temperature of 30°C for 48 h. Isolate identification was performed using an internal transcribed spacer and S. cerevisiae -specific primers. Molecular markers, specifically sequence-related amplified polymorphism (SRAP) and inter-simple sequence repeat (ISSR), were used to determine the genetic diversity. Polymorphic information content was estimated, and genotype-specific markers were detected. A phylogenetic relationship was established based on data obtained from the molecular markers. Results and conclusion S. cerevisiae- specific primers confirmed that all 36 yeast isolates belonged to the S. cerevisiae species. Molecular identification was achieved through amplification of internal transcribed spacer sequences, followed by sequencing and database matching. Phylogenetic analysis further confirmed their classification as S. cerevisiae . Genetic diversity among the 36 strains was assessed using SRAP and ISSR markers, which show 23.4 and 30 polymorphism percentages, respectively. The results revealed that 26 SRAP and 18 ISSR genotype-specific markers were identified for the 36 S. cerevisiae isolates. The cluster analyses indicated that the strains were separated into 20 distinct clusters based on their genetic similarities. These findings demonstrate the effectiveness of S. cerevisiae -specific primers, molecular identification techniques, and genetic marker analyses in characterizing and understanding the genetic diversity and relatedness within a population of S. cerevisiae isolates.