Optimization of process parameters for production of antimicrobial metabolites by an endophytic fungus Aspergillus sp. CPR5 isolated from Calotropis procera root.

Abstract

Objective: To study the antimicrobial activity of crude ethyl acetate extract from endophytic fungus in Calotropis procera root.Methods: Endophytic fungus was screened for production of antimicrobial metabolites. Fermentation was carried out in 500 ml Erlenmeyer flask. Disc diffusion method was used to test antimicrobial activity of crude extract using chloramphenicol sulfate and fluconazole as a positive control.Results: A total of 14 endophytic fungi were isolated (CPR1-CPR14). Among these 14 isolates, CPR5 was found to show maximum antimicrobial activity, in compare to other isolates, against Gram-positive, Gram-negative bacteria and fungi. The antimicrobial activity was tested in opposition to Escherichia coli, Pseudomonas aeroginosa, Bacillus subtilis, Staphylococcus aureus, Ralstonia solanacearum, Xanthomonas oryzae, Penicillium chrysogenum, Candida albicans, Phoma exigua, Sclerotium rolfsii, and Sclerotinia scleratiourum. Minimum inhibitory concentration of crude extract against test microorganisms was determined. Fungus was identified as Aspergillus sp. production parameters (temperature, pH, carbon source, nitrogen source, and sodium chloride concentration) were optimized. Conclusion:Crud extract produced by the isolated endophytic fungus could be an important source of broad-spectrum antimicrobial metabolites.

Effect of Ampicillin and Chloramphenicol on Chick Serum

“…It inhibits the process of mitochondrial protein synthesis [26]. Addition of this antibiotic on chick serum indicates the role of chloramphenicol on chick serum and also validates Beer-Lambert's law (Table 6).…”

Antibacterial activity of endophytic fungus, Penicillium griseofulvum MPR1 isolated from medicinal plant, Mentha pulegium L.

“…Anwar and Iqbal (2017) also studied the effect of growth media on antibacterial activity, and suggested that secondary metabolites are highly affected by the composition of the growth medium. Verma et al (2017) found that starch was the source of carbon allowing the endophytic fungus to produce the highest amount of bioactive molecules followed by glucose. This is in agreement with the results obtained with MPR1 on PDA and MEA that contain the appropriate concentration of starch and glucose.…”

Bioprospecting of endophytes in medicinal plants of Thar Desert: An attractive resource for biopharmaceuticals

“…It has been reported that each group of plants from thallophytes to spermatophytes and from hydrophytes to xerophytes harbor endophytic microbiota [ [35] , [36] , [37] ]. Endophytes like fungus, bacteria, and actinomycetes have been found as the most useful and greatly diverse group of microbiota to reside within the plants of the different part of the globe, such as rainforests [ 38 ], oceans [ 39 ], mangrove swamps [ 40 ], Arctic [ 41 ], Antarctic [ 42 ], coastal forests [ 43 ], geothermal lands [ 44 ], and deserts [ 45 ].…”

“…They also have been isolated from ferns, gymnosperms, and angiosperms of the tropical forests, diverse xeric climates, extreme arctic flora, and boreal forests [ 46 , 47 ]. There are myriad reports indicates that diversified environmental conditions comprising drought [ 32 , 33 ], low temperature [ 48 ], elevated temperature [ [49] , [50] , [51] ], high salinity [ 52 ], and multiple extreme conditions [ [35] , [36] , [37] , 53 ] are responsible for niche-specific diversity of the microbial community. Moreover, the term endophyte is a topographical term that comprises all the organisms that asymptomatically reside within the living internal tissues of the plant parts of the host at any stage of their life.…”

“…Identification of the fungal strains based on the type of colony, reproductive structure, and internal transcribed spacer (ITS) region analysis revealed that the predominant fungal strains belonged to the species Aspergillus , Phoma , and Penicillium [ 86 ]. Verma et al [ [35] , [36] , [37] ] found Aspergillus niger to predominant fungal isolates among 14 endophytic isolates from the root of the C. procera . Chowdhury et al [ 84 ] identified and characterized four endophytic fungi by 18S rRNA sequencing approach namely, Pencillium sp., Aspergillus sp.…”