Study on the potential of cold-active lipases from psychrotrophic fungi for detergent formulation

Abstract

Lipases from psychrotrophic fungal isolates BPF4 and BPF6 identified as Penicilium canesense and Pseudogymnoascus roseus respectively were characterized for their compatibility towards laundry detergent. BPF4 and BPF6 lipases showed maximum activity at pH 11 and 9 respectively and at 40 °C. The residual activities at 20 °C and 4 °C of BPF4 lipase were 35% and 20% and of BPF6 lipase were 70% and 20 °C respectively. Both the enzymes were stable at 4 °C, 20 °C and 40 °C for 2 h losing at the most 20% of activities. Both the enzymes were metalloenzymes with activity enhancement by nearly threefold by Ca²⁺. Contrary to BPF6 lipase, BPF4 enzyme was not stimulated by EDTA nor inhibited, rather stimulated by SDS and Triton X-100 by 125% and 330% respectively. Both the lipases showed minor to moderate inhibition by NaClO₃ and H₂O₂, and exhibited nearly 90% residual activity after 1 h of incubation in selected detergent brands thus indicating potential for their inclusion in detergent formulation thereby facilitating cold-washing as a step towards mitigation of climate change.

Keywords: Cold-active lipases; Detergent lipases; Penicilium canesense BPF4; Pseudogymnoascus roseus BPF6; Psychrophilic fungus; Psychrotolerant fungus.

Fig. 1

Phylogenetic relationship with 10 closely related isolates retrieved from Genbank on the basis of ITS sequences of fungal isolates (a) BPF4 and (b) BPF6.

Fig. 2

Effect of temperature on the activity of (a) BPF4 lipase and (b) BPF6 lipase.

Fig. 3

Effect of pH on the activity of (a) BPF4 lipase and (b) BPF6 lipase.

Fig. 4

Effect of temperature (4°C, 20 °C and 40 °C) on the activity and stability of (a) BPF4 lipase and (b) BPF6 lipase.

Fig. 5

Effect of higher temperature (50 °C) on the stability of (a) BPF4 lipase and (b) BPF6 lipase.

Fig. 6

Effect of selected laundry detergent brands on the activity of (a) BPF4 lipase and (b) BPF6 lipase.

Supplementary Figure 1