Bioactivities of Mangrove-Associated Filamentous Fungi from Jepara, Indonesia: Anti-Bacterial Metabolites and Wood-Degrading Enzymes.

Abstract

Background: Mangrove-associated fungi are widely known due to their bioactivities, especially their antibacterial and lignocellulose-degrading enzymes activity. However, research on their bioactivity in Indonesia, particularly in Jepara Regency remain limited. This research aims to explore the antibacterial and wood-degrading enzymatic properties from mangroves-associated fungi of Jepara, Indonesia.

Methods: A total of 43 isolates were successfully collected from leaf and barks of Excoecaria agallocha, Acanthus ilicifolius, as well as Lumnitzera racemosa. Antibacterial screening against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was then conducted to all isolates, where 1 isolate was active against E. coli, 12 against S. aureus, and 5 isolates active against both pathogens. All active isolates were identified through microscopic observation.

Results: Isolates with the most consistent inhibition zone, namely AB1, E2D2, E2B4, and LB10 continued to have metabolite extraction and antibacterial assay through disc-diffusion methods against the same 2 pathogens. Isolate E2B4 was able to produce the largest halo zone diameter measuring 22.28±1.59 mm at concentration of 50 mg/mL against S. aureus. Based on preliminary phytochemical screening, crude extract of E2B4 contains flavonoid and alkaloid as secondary metabolite. To search for further bioactivity, wood-degrading enzymatic assay was conducted, where the result showed that 6 isolates were actively produced cellulase, 1 laccase, 7 tannase, and 5 lignin peroxidase. DNA barcoding revealed that AB1, E2D2, and E2B4 isolates were identified as Phaeophleospora eucalypticola, Curvularia lunata, and Paraconiothyrium sp., respectively.

Conclusion: Therefore, these findings highlight mangrove-associated fungi bio-activities potential through screening assay and provide critical information regarding the rarely studied Indonesian fungi.