Antimicrobial, antioxidant, and cytotoxic properties of endophytic fungi isolated from Thysanolaena maxima Roxb., Dracaena spicata Roxb. and Aglaonema hookerianum Schott.

Abstract

Background Endophytic fungi have recently been recognized as an impressive source of natural biomolecules. The primary objective of the research was to isolate fungal endophytes from Thysanolaena maxima Roxb., Dracaena spicata Roxb. and Aglaonema hookerianum Schott. of Bangladesh and assess their pharmacological potentialities focusing on antimicrobial, antioxidant, and cytotoxic properties. Methods The fungal isolates were identified up to the genus level by analyzing their macroscopic and microscopic characteristics. Ethyl acetate extracts of all the fungal isolates were screened for different bioactivities, including antimicrobial (disc diffusion method), antioxidant (DPPH scavenging assay), and cytotoxic (brine shrimp lethality bioassay) activities. Results Among the thirteen isolates, Fusarium sp. was the most recognized genus, while the others belonged to Colletotrichum sp. and Pestalotia sp. Comparing the bioactivity of all the extracts, Fusarium sp. was shown to be the most effective endophyte, followed by Colletotrichum sp. and Pestalotia sp. In the antimicrobial study, two isolates of Fusarium sp. (internal strain nos. DSLE-1 and AHPE-4) showed inhibitory activity against all the tested bacteria and the highest zone of inhibition (15.5 ± 0.4 mm) was exerted by AHPE-4 against Bacillus subtillis. All the fungal isolates produced mild to moderate free radical scavenging activity, where the highest antioxidant activity was revealed by one isolate of Fusarium sp. (internal strain no. AHPE-3) with an IC50 value of 84.94 ± 0.41 µg/mL. The majority of Fusarium sp. isolates exhibited notable cytotoxic activity, where AHPE-4 exhibited the highest cytotoxicity, having the LC50 value of 14.33 ± 4.5 µg/mL. Conclusion The findings of the study endorsed that the fungal endophytes isolated from T. maxima, D. spicata, and A. hookerianum hold potential as valuable origins of bioactive substances. Nevertheless, more comprehensive research is warranted, which could develop novel natural compounds from these endophytes to treat various infectious and cancerous diseases.

Phytochemical characterization, antimicrobial and antioxidant activities of Terminalia catappa methanol and aqueous extracts

“…For the measurement of absorbance of the test solutions by UV-Vis spectrophotometer, Microprocessor double beam model: AVI-2704 (Avi scientific India) 517 nm was used, with methanol as the blank. The radical scavenging activities (RSA) of the studied extracts were calculated using the formula below [28]. The amount at which the sample gives 50% inhibition (IC50) scavenging activity was determined by plotting the graph against the concentrations of the sample.…”

“…The capacity of the crude extracts to reduce the stable free radical from DPPH was used as a quantitative determination of free radical scavenging properties [29]. This was determined by measuring absorbance using a UVvis spectrophotometer at a wavelength of 517 nm [28]. The relative scavenging activities and IC 50 values of the extracts and ascorbic acid were determined (Table 4).…”

Anti-HIV Activity and Immunomodulatory Properties of Fractionated Crude Extracts of Alternaria alternata

“…Endophytic fungi, for example, synthesise chemically complex compounds that confer a selective advantage to the plant host in natural environments [ 7 ]. Secondary metabolites produced by endophytic fungi have a high level of chemical and structural diversity, with a range of bioactive properties, including cytotoxic, immunosuppressive, antimicrobial, antimalarial, antiviral, and antioxidant [ 8 , 9 , 10 , 11 ].…”