Biosynthesis of gold nanoparticles by biotechnologically important active and inactive form of the ascomycetes-pichia membranifaciens and debaryomyces hansenii

The two biotechnologically important Ascomycetes, Pichia membranifaciens and Debaryomyces hansenii, were tested (in active and inactive form), in the present study for efficient bioreduction of trivalent aurum to gold nanoparticles. Strong surface plasmon resonance was observed, between 530 and 540 nm, from the gold nanoparticles recovered from the test Ascomycetes. The characterization of the gold nanoparticles thus formed was performed by HR-TEM, FE-SEM, FTIR spectroscopy. Comparing the active and inactive form of the two Ascomycetes, the inactive form showed better productivity and recovery of gold nanoparticles. It was also found that P. membranifaciens is more productive in terms of time, quality and quantity, than D. hansenii. The nanoparticles were relatively monomorphic in P. membranifaciens than in D. hansenii. The present study also presents a promising outlook towards the effective recycling of the bioactive wastes.