Molecular profiling and bioactive potential of an endophytic fungus Aspergillus sulphureus isolated from Sida acuta : a medicinal plant

Abstract

Context: Sida acuta Burm.f. (Malvaceae) extracts are reported to have applications against malaria, diuretic, antipyretic, nervous and urinary diseases. No fungal endophytes of S. acuta are reported. Objective: Isolation, identification and evaluation of antibacterial, antioxidant, anticancer and haemolytic potential of fungal endophytes from the ethnomedcinal plant S. acuta. Materials and methods: Sida acuta stem segments were placed on PDA medium to isolate endophytic fungi. The fungus was identified by genomic DNA analysis and phylogenetic tree was constructed using ITS sequences (GenBank) to confirm species. The antibacterial efficacy of Aspergillus sulphureus MME12 ethyl acetate extract was tested against Gram-positive and Gram-negative pathogenic bacteria. DPPH free radical scavenging activity, anticancer and DNA fragmentation against EAC cells, and direct haemolytic activity (100-500 lg/mL) using human erythrocytes were determined. Results and discussion: The ethyl acetate extract of A. sulphureus (Fresen.) Wehmer (Trichocomaceae) demonstrated significant antibacterial potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi compared to streptomycin. MIC against test pathogens was in the range of 15.6-62.5 lg/mL. The antioxidant results revealed significant RSA from 12.43% to 62.02% (IC 50 ¼ 350.4 lg/ mL, p 0.05). MME12 offered considerable inhibition of EAC proliferation (23% to 84%, IC 50 ¼ 216.7 lg/mL, p 0.05) supported by DNA fragmentation studies. The extract also offered insignificant haemolysis (5.6%) compared to Triton X-100. Conclusions: A single endophytic fungus, A. sulphureus MME12 was isolated and identified using molecular profiling. The above-mentioned findings support the pharmacological application of A. sulphureus MME12 extract and demand for purification of the active principle(s).

Isolation and Characterization of Fungal Endophytes Isolated from Medicinal Plant Ephedra pachyclada as Plant Growth-Promoting

“…In the same regard, PGPF promotes plant growth by nitrogen fixation and phosphate solubilizations [ 10 ], the production of different enzymes, such as amylase, cellulase, urease, catalase, and protease [ 7 , 11 ], in addition to ammonia production [ 12 ]. Moreover, fungal endophytes have high potential to protect plants against different pathogens and, hence, reduce crop loss through the secretion of different bioactive compounds such as antibiotics [ 13 ].…”

Fungal Endophytes as Growth Promoters and Inducers of Resistance in Tomato (Lycopersicon esculentum Mill.) against Alternaria solani

“…Among the microorganisms of importance, endophytic fungi are gradually gaining importance in biocontrol strategies as they are previously known to produce many secondary metabolites of importance to human welfare in various fields. 40,13,11,15 Hence, in the study endophytic fungi isolated from some of the medicinally important plants and screened for their effectiveness against the induction of resistance against the early blight disease and plant growth promotion in tomato. A total of five medicinal plants namely S. macranthum, D. indica, S. glauca, C. quadrangularis and C. alata were collected from the Mysore region and 78 endophytic fungi were isolated following the imprint method.…”

“…[5][6][7] Endophytes (both fungi and bacteria) are the microorganisms that inhabit inter/ intra cellularly within the host forming systemic or local associations showing mutuality to that of a symbiotic relationship without causing apparent disease symptoms. [8][9][10][11] These endophytes are often known to promote plants' growth, recycle nutrients, fitness and improve their ability to cope with stress. [12][13][14][15] Among the different forms of endophytes, myco-endophytes have been least explored compared to that of bacterial forms irrespective of their application in the scientific field.…”

The Evaluation of Antimicrobial and Antibiofilm Activity of Bioactive Compounds Obtained from Aspergillus Sclerotiorum

“…Using the same method, Murali et al (2017) have reported that evaluated the antibacterial potential of Aspergillus sulphureus isolated from Sida Acuta. Similar data were obtained for S. aureus in this study.…”

“…Santos et al (2015) reported that among the 18 fungi isolates, Nigrospora sphaerica (URM-6060) and Pestalotiopsis maculans (URM6061) gave the best results against test pathogens similarly. Thin-layer Chromatography(TLC) and Overlay Murali et al (2017) reported that TLC bioautography is the ideal method for separation of bioactive compounds. Extraction of culture filtrate with ethyl acetate is a good solvent for distinguishing bioactive compounds from other substances that may be present in filtrate.…”