Isolating Yeasts from Aqueous Sediments and Investigating their Enzymatic Properties

The aquatic sediments of the rivers and the Caspian Sea provide numerous microscopic habitats for a large community of microbial organisms that are actively producing fuel enzymes due to favorable conditions.

Surface sediment sampling of the Sefidrood, Siahrood, and Haraz rivers as well as the Caspian Sea was carried out. The samples were cultured in YGC agar medium by the pour plate method. Fungi grown on these plates were examined for the presence of Protease, Amylase, Lipase, Dnase, Chitinase, Lectinase and Pectinase. Then, the differentiation between yeast isolates was performed by chromagar media; the molecular identification of the isolated yeasts was performed by PCR and sequencing of PCR products.

A set of four isolates was isolated from fourteen stations in three stages by sampling of rivers and Caspian sediments after continuous sequencing and cultivation on YGC Agar. All isolates produced Lipase, DNase and Amylase. Two isolates produced Protease and Lisetinase. None of the isolates had the ability to produce Chitinase and Pectinase. Two isolates, SHOO2 and SHOO7, had the most diverse enzyme production. Biochemical and morphological identification of four isolates was also performed accurately, and then genetic identification of two isolates SHOO2 and SHOO14 was performed, which were similar to Candida tropicalis species and Candida fameta, respectively.

Based on the available sources, there have been reports of Pectinase and Kinase activity in yeasts isolated from different sources. To justify this observation, it can be said that the region was affected by the isolation and the enzymatic activity of the isolated yeasts.Aquatic sediments can be a good source of yeasts with the ability to produce a wide range of useful enzymes needed in the industry.