Preliminary study of fungi from mangrove sediments as a bioremediation agent of lead (Pb) heavy metal

Abstract

The mangrove ecosystem in Tapak Village is one of the coastal areas in Tugu District, Semarang, Central Java and close to the industrial area. This mangrove ecosystem presumed to be contaminated by heavy metals. This study aims to analysis of lead heavy metal in Tapak, isolate fungi from mangrove sediments, and identify the potential fungus according to molecular approach. The sampling method used a purposive random sampling method with 4 sampling points. The isolation of fungi was carried out using the dilution method and then cultured on the general Potato Dextrose Agar (PDA) media. The purified isolates were tested its ability as a bioremediation agent of lead heavy metal (Pb) and were identified molecularly using ITS1 and ITS4 as universal primers. The results of the analysis of the Pb content in the sediment samples using the Atomic Absorption Spectrophotometer (AAS) ranged from 59.07-76.76mg/Kg, where these results exceeded the CCME (Canadian Council of Ministers of the Environment) quality standards, 2001, with Pb standards of 35mg/Kg. Based on the screening of fungal isolates on media supplemented with (Pb) of 70 ppm, a total 18 isolates were purified. There were 9 isolates with the fastest growth in observations for 7 days. One of the 9 fastest-growing isolates, MT.1.E, was identified molecularly using Internal Transcribe Spacer (ITS) region and the homology was closely related to Aspergillus fumigatus which has a 100% similarity. According to this study, fungi can be proposed as a bioremediation agent.