Abstract
Background:
The fungi Rhodotorula species are widespread airborne contaminants and are thought to be natural occupants of human skin, lungs, urine, and feces. Rhodotorula mucilaginosa, R. minuta, and R. glutinis are the three most prevalent species.
Aim:
The purpose of this study is to isolate Rhodotorula mucilaginosa from cow rumen fluid in the province of Mosul, as well as to determine how laser light irradiation affects the growth and morphological traits of this organism.
Methods:
From the fluid rumen of AL-restaki and AL-karadi cows, the Rhodotorula mucilaginosa was isolated. Using a traditional approach and the ID-Yst card system Vitek 2, isolated colonies were purified, recognized, and described. A semiconductor laser system with a power of 50 mW and a wavelength of 450 nm was used in the experiment to evaluate the light laser irradiation effects on the direct culture growth of Rhodotorula mucilaginosa under two light irradiation conditions of 30 and 60 minutes.
Results:
According to traditional methods and the ID-Yst card system Vitek 2, Rhodotorula mucilaginosa predominated 7/30 (23.3%), and these strains effectively thrived on medium containing dextrose agar as evidenced by the carotenoid pigments that gave their colonies a salmon-pink to coral-red hue. When compared to a control group where no laser was used, the impact of light laser irradiation was assessed 24 hours after the irradiation using a biomass (dry weight measuring yeast cell content in suspension) and microscopic analysis using Gram stain. The irregular shape of the cells and their link to one another were shown by macroscopic and microscopic examinations. The irradiated culture subculture on sabouraued dextrose agar and incubation at 37 C for 3 days demonstrated inhibited growth in 4/7 (57.1%) isolates. Also, there was no discernible difference between the control group and the Rhodotorula mucilaginosa biomass concentration under light irradiation circumstances (30 and 60 min).
Conclusion:
This was the first study identifying Rhodotorula mucilaginosa in Iraqi cow rumen fluid.

Key words: Laser application, Rhodotorula mucilaginosa, Rumen fluid of cow