Antifungal, anticoagulant, thrombolytic and antioxidant activities of gold nanoparticles phytosynthesized from blighia sapida husk extract

Abstract

The green synthesis of gold nanoparticles (AuNPs) using crude aqueous extract of Ackee (Blighia sapida) husk as a reducing/capping agent was investigated for its antifungal, anticoagulant and thrombolytic activities in this work. The synthesis of AuNPs was monitored through the colour change for 15 min at photoactivation which turned out to be dark brown colouration and further characterized using UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The UV-visible spectrum of the AuNPs displayed a clear peak at 556.0 nm which was not observed in the spectra of the aqueous gold chloride and the crude aqueous extract of the plant. The prominent peaks of AuNPs in FTIR spectrum were 3792.9, 3346.2, 2971.4 and 1704.9 cm-1 which lent credence to the fact that proteins and phenolic compounds were involved in the biofabrication and capping of the AuNPs. Energy dispersive X-ray (EDX) analysis showed that gold (Au) was the prominent metal present; the AuNPs were fairly spherical with sizes ranging from 23 to 126.7 nm. The biosynthesized AuNPs showed a significant effect against the growth of Can-dida albicans (38.0%), Aspergillus niger (50%), Aspergillus flavus (63.4%), As-pergilus fumigatus (61.4%) and Fusarium solani (58.9%). The free radical scavenging properties of the AuNPs were very potent against the stable organic free radical DPPH, the varying concentration of the AuNPs (10, 20, 40 and 60 μg/ml) scavenged DPPH by 80.75, 81.11, 87.91 and 89.34%. Furthermore, the AuNPs showed anticoagulant activities of 48.70, 49.13, 50.00 and 54.74% at 250, 500, 750 and 1000 μg/ml and thrombolytic activities of 54.31, 56.46, 75.00 and 96.12% at 250, 500, 750 and 1000 μg/ml. The biomedical and antifungal properties of AuNPs against toxigenic/pathogenic fungi established in this research work would grant lasting solutions to many medical, agricultural and biotechnological challenges in this dispensation.