The isolation and molecular characterization of uv-protective pigment producing fungi for using in commercial formulations of fungal biopreparats

The ultraviolet radiation from sunlight is the most important factor affecting the viability of entomopathogenic fungi. The UV protectants are added to the formulated conidia in most applications to increase the persistence of microbial agents in the environment. However, the field efficiency of the formulated conidias in many cases are still not sufficient to control the pests. So, there is a need for the discovery of new UV protection products such as pigments. For this purpose, soil samples, 1800 m and above altitude in Erzurum, were collected at 20 different points. Isolation studies in the laboratory, 2 filamentous fungi and 6 yeasts were identified that produced pigment. In this preliminary selection, only the A2 and A3-coded yeast isolates from this pigment producer fungus were selected because of their susceptibility to pigment extrusion and the pigments purified. The pigment samples of these two isolates were then added to B. bassiana spore suspensions as 0.5 mg / ml, 1 mg / ml and 2.5 mg / ml. The suspensions added with pigment were exposed to UV rays for 15, 30 and 60 minutes. In the light of the results obtained, the addition of pigments increased the conidial germination by providing protection against UV rays in all experiments. The best results were obtained by the addition of pigment, which is belonged to the A2 isolate. As a result of exposed to the UV light for 30 minutes of B. bassiana isolate, which is coded PaF04, the conidia germination rate decreased to 39.58%, while the addition of A2 pigment at a concentration of 0.5 mg / ml was recorded as 99.16%.Therefore, the antimicrobial properties of the A2 pigment, the antioxidant activity and the molecular characterization of the yeast have been realized. As a result of the studies carried out, it was concludedthat the pigment exhibits antioxidant activity as well as UV protective properties. In addition, while showing antibacterial properties against Gram negative and Gram positive bacterial, it did not show antifungal activity. According to the results of ITS sequence analysis, A2-coded isolate was identified as Sporobolomyces roseus and deposited with the GenBank database under the accession number KY705066.