Biological Activities of the Alkaloid Quinazoline Extracted from Aspergillus nomius

TWENTY FIVE Aspergillus isolates were screened from Giza Governorate and Saint Catherine Protectorate soils in Egypt. The antimicrobial activity of the crude extracts was tested against two Gram positive bacteria (Bacillus subtilis NRRL-B-4219, Staphylococcus aureus ATCC29213), four Gram negative bacteria (Alcaligenes faecalis B-170, Escherichia coli ATCC25922, Klebsiella pneumoniae ATCC10131, Pseudomonas aeruginosa ATCC27953), and one yeast (Candida albicans ATCC10231). The antioxidant activity using free radical scavenging model was assayed for the crude extracts. The antitumor activity for all of crude extracts was determined against HCT116 (Colon carcinoma cell line), HEPG2 (Liver carcinoma cell line), and MCF-7 (Breast carcinoma cell line). Aspergillus nomius was the most potent fungal species accordingly, it was chosen for bioactivity assay. Identification of this species was further confirmed at the molecular level based on nuclear ribosomal DNA 18s identities. An accession number, LC199488, was given at the DDBJ GenBank. The column chromatography of its crude extract yielded five distinguished fractions. The biological (antimicrobial, antioxidant and antitumor) activities of these fractions were assayed. Fraction B proved to be of most potential. HPLC analysis of this fraction showed that there was a sharp and clear peak at about 18.1 min. This denoted the presence of an active compound. The compound at this peak was purified and its structure was elucidated via 1HNMR and 13CNMR spectroscopy. It was concluded that it would be 1,2,3,9 tetrahydropyrrolo [2,1-b] quinazolin-3-ol.