Biological Evaluation of Endophytic Fungus, Chaetomium globosum JN711454, as Potential Candidate for Improving Drug Discovery

Abstract

The main objective of this research work focused on investigating the biological and chemical aspects of endophytic fungus Chaetomium globosum, for pharmaceutical purposes to improve the drug discovery process. The endophytic C. globosum was isolated from healthy leaves of Egyptian medicinal plant Adiantum capillus-veneris collected from Saint Katherine Protectorate, Sinai, Egypt. The identification of C. globosum was on the basis of classical and molecular taxonomy. Gene encoding for 18S rRNA was partially sequenced, submitted to the GenBank and got the accession number JN711454, to resolve the phylogenetic relations with fungal ancestor using phylogenetic tree. To explore the biosynthetic power of endophytic C. globosum JN711454, the fungus was cultivated over five different media, oatmeal, rice, yeast malt glucose, potato dextrose agar (PDA) and Czapek's dox media, for 3 weeks at 30 °C, followed by extraction with different solvents, ethyl acetate (EA), and methanol. The ethyl acetate extract of C. globosum cultivated on PDA medium was the most potent extract. It showed strong antioxidant activity with EC50 11.5 μg/ml, potent anticancer activity with 55 % toxicity toward HepG-2 cells at 100 μg/ml and 66 % cytotoxicity to FGC4 cells at 250 μg/ml, promising butyrylcholinesterase inhibitory activities (>85 %), and moderate antimicrobial and stopped the attachment of HSV-2 virus to VERO cells. The metabolomic profiling of PDA-EA extract using LC-MS revealed the presence of several metabolites to which the observed bioactivities could be attributed. Here we report for the first time inhibitory activity of endophytic C. globosum JN711454 secondary metabolites to butyrylcholinesterase, one of neuro hydrolase enzymes that play a major role in development of Alzheimer's disease.

Antiviral and Antioxidant Potential of Fungal Endophytes of Egyptian Medicinal Plants

“…Accordingly, we concluded that the host-microbe interaction is one of the driving forces for endophytic secondary metabolites production [3][4][5]8]. The previous results confirmed that C. globosum was considered as a promising source of bioactive metabolites which could be used in drug industry [10].…”

“…Of all the 99 crude extracts, only Chaetomium globosum isolated from the internal tissues of Adiantum capillus-veneris revealed a promising antioxidant activity (99%) DPPH scavenging activity at the level 100 µg/mL of total extract (Table 2). Genetic identification (18S rDNA) of the active antioxidant isolate was achieved in our previous report [10]. It showed a high similarity to Chaetomium globosum.…”

“…It showed a high similarity to Chaetomium globosum. The sequence of the fungus nucleotides was submitted to GenBank to estimate DNA similarities, and was assigned the accession number JN711454 [10]. In our previous study [10], we attributed the antioxidant potential of C. globosum to the phenolic compounds.…”

“…The sequence of the fungus nucleotides was submitted to GenBank to estimate DNA similarities, and was assigned the accession number JN711454 [10]. In our previous study [10], we attributed the antioxidant potential of C. globosum to the phenolic compounds. The phenolic hydroxyl groups are considered as functional and characteristic groups responsible for the main antioxidant activity.…”

“…Nowadays, this area attracts more attention for studying the diversity of endophytic mycobiota from medicinal plants [8,9]. The importance of compounds with antioxidant activity is their protective effect against the oxidative stress caused by oxygen-derived free radicals [10]. The culture filtrate of Pestalotiopsis microspora, which was isolated from combretaceaous plant Terminalia morobensis, showed promising antioxidant activity [11].…”