Angio-Suppressive Activity and Molecular Identification of Aspergillus niger strain ArMCN-01 Endophytic on Avicennia rumphiana

Abstract The escalating global burden of cancer necessitates the exploration of novel therapeutic agents, particularly those targeting angiogenesis—the physiological process critical for tumor growth and metastasis. This study evaluated the angio-suppressive potential of the ethanolic extract of Aspergillus niger (ArLEFEE), an endophytic fungus isolated from the leaves of the "Vulnerable" mangrove species Avicennia rumphiana (Api-api) collected in Barangay Catandunganon, Mercedes, Camarines Norte, Philippines. This isolation establishes A. rumphiana as a novel host record for this fungal endophyte. The fungal isolate was definitively identified as a novel strain, designated as Aspergillus niger strain ArMCN-01, through morphological characterization and molecular sequencing of the ITS1-5.8S-ITS2 region (99.67% similarity), with genetic data deposited in GenBank (Accession No. PX567897) and the Barcode of Life Data Systems (Process ID: MNGPH001-25). Qualitative phytochemical profiling of the crude extract revealed the presence of bioactive secondary metabolites, specifically flavonoids, polyphenols, and tannins, while alkaloids were absent. The biological activity was assessed using the in vivo Duck Chorioallantoic Membrane (CAM) assay. Results demonstrated a statistically significant dose-dependent inhibition of neovascularization (ANOVA: F=5.65, p=0.027). Post-hoc analysis identified the 1.25% concentration as the optimal therapeutic dose, achieving a statistically significant reduction in vessel formation (p=0.0229) comparable to the positive control. Hierarchical vascular analysis revealed a targeted anti-sprouting mechanism, characterized by an 85.65% reduction in Tertiary Blood Vessels and a 70.71% reduction in vascular branching points. However, concentrations exceeding 1.25% exhibited potent cytotoxicity, leading to embryo mortality. These findings confirm that A. niger ArMCN-01 produces pharmacologically active metabolites that disrupt the structural integrity of the neovasculature, validating the Avicennia rumphiana mangrove ecosystem as a vital reservoir for potential anti-cancer drug discovery. The comprehensive dataset is openly accessible via Zenodo (DOI: 10.5281/zenodo.17764232). Note: This dataset includes raw ITS rDNA sequencing chromatograms, phylogenetic tree alignments, phytochemical analysis reports, and raw vessel counts from the Duck Chorioallantoic Membrane (CAM) assay.