*2.1. Chemicals Used*

In the current study, magnesium nitrate hexahydrate (Mg (NO3)2·6H2O) and sodium hydroxide (NaOH) were used as analytical grade and obtained from Sigma Aldrich, Cairo, Egypt. The Malt Extract agar (MEA) media used for fungal isolations and Mueller-Hinton agar media used for antimicrobial activities were ready-made (Oxoid, Cairo, Egypt). All biological reactions were carried out using distilled water (dis. H2O). The tannery wastewater was collected from Robbiki Leather City, 10th of Ramadan, Cairo, Egypt (GPS: 30◦17′898′′ N, 31◦76′840′′ E).
