ANALISIS HASIL OKSIDASI BROMOCRESOL PURPLE OLEH LAKASE Trichoderma asperellum LBKURCC1 MENGGUNAKAN SPEKTROFOTOMETER FOURIER TRANSFORM INFRA RED

Abstract

Trichoderma asperellum LBKURCC1 is one of the biocontrol agents capable of producing the enzyme laccase. Laccase (EC 1.10.3.2) is an extracellular enzyme that contains copper ions and catalyzes the four-electron oxidation of various -OH containing substrates. T. asperellum LBKURCC1 laccase is able to oxidize several triphenylmethane textile dyes, including Bromocresol purple (BCP) dye. This study explores chemical changes of the dye, Bromocresol purple (BCP) by treatment with crude extracts of T. asperellum LBKURCC1 by analyzing its Fourier Transform Infra Red (FTIR) spectrum to determine changes in functional groups. The FTIR results did not show any addition or reduction of functional groups in BCP buffer controls, in BCP treated with the inactive enzyme, and with BCP treated with the active enzyme for 30 minutes and 6 days, respectively. However, there was a slight difference in the FTIR spectrum between 30 minutes and 6 days treatments, for all experiments, namely a decrease in the stretching of 2850 cm-1 due to the widening of the O-H stretching. This indicates that BCP is oxidized and leads to a more polar compound because the intensity of the O-H stretch increases and C-H which is a non-polar group decreases.