Molecular identification and Anticandidal Activity Assessment of Desmodesmus subspicatus Against Multidrug-Resistant Candida Isolates from Intensive Care Units

Desmodesmus exhibits significant morphological diversity, leading to multiple synonyms being assigned to this species based solely on optical microscopic morphology. Prior studies have demonstrated that Candida spp. displays increased resistance in critical care units relative to non-ICU isolates. In the current study, the green alga Desmodesmus subspicatus (Scenedesmaceae) from AL-Hilla River in Iraq was isolated, purified, and identified morphologically via optical microscope and at the level of molecular using 5.8S ribosomal RNA genes, as well as the isolate species recorded in NCBI gene bank with PQ192620.1. Using the MEGA and BLAST programs, we constructed a phylogenetic tree and analyzed the similarities and differences with international isolates. The results showed that the antifungal activity of the alcoholic extract of the algae Desmodesmus subspicatus against C. dubliniensis had a standard deviation of 4.66 and a mean inhibition zone of 23.90. The average inhibition zone against Candida albicans was 25.23, with a standard deviation 5.54. C. glabrata had an inhibition zone with an average of 24.20 and a standard deviation of 4.04.