Antimicrobial, and Antibiofilm Forming Activities of Red Pigment of Talaromyces marneffei Strain SA2a on Multidrug-Resistant Burkholderia sp.

Abstract

Burkholderia are Gram-negative bacteria found in moist environments, soil, and water, where they can survive for months. These bacteria are resistant to several antibiotics of choice in treating Burkholderia-associated infections and diseases. This study aims to evaluate the activities of red pigment of Talaromyces marneffei on multidrug-resistant Burkholderia sp. Pigment producing fungus was obtained from microbial culture collections and it was properly identified by sequencing of the 18S rRNA partial sequence. Red pigment from the fungus was extracted with ethyl acetate and characterized with a UV-visible spectrophotometer, FTIR, and GCMS. Antibacterial activities of the pigment were determined on multidrug-resistant Burkholderia pseudomallei and Burkholderia cepacia complex isolates with agar well diffusion method. Antibiofilm formation was evaluated in 96-well microtiter plates and antioxidant properties were also determined. The molecular characterization identified the fungus as Talaromyces marneffei strain SA2a. The ethyl acetate efficiently extracted the pigment, and UV-visible identified the red pigment as purpuride at a wavelength of 512nm. The FTIR revealed the functional group as alkanes, esters, and carbonyl groups, and the GCMS showed the prominent compounds in the pigment as Ethanol, 2-nitro- (m/z 91.07), Bis(n-propylthio)methane (m/z 164.3), Acetic acid (m/z 60.05), and Purpuride (m/z391.5). The pigment demonstrated good inhibitory potential on 18(90%) of the B. pseudomallei and 11(85%) of the B. cepacia complex isolates at 200mg/mL-12.5mg/mL with zones of inhibition around the wells. The pigment prevented biofilm formation with 25 - 96% biofilm inhibition on B. pseudomallei and 19 - 94% on B. cepacia complex isolates. The crude pigment showed 48.22% DDPH scavenging activities at the lowest concentration of 100mg/mL, 11.37±0.04 FRAP content at 100mg/mL and 11.58±0.01 ABTS at 100μg/mL. The result of this study suggests that the pigment of Talaromyces marneffei could be a promising alternative therapy in treating Burkholderia infections. Further research is required to show these potential applications in pharmaceutical industries for drug production.