Fig. 3

Determining EG in PG using enzymatic assays. PG was spiked with different percentages of EG. (a) End-point 340 nm absorbance readings of NADH after using alcohol dehydrogenase and aldehyde dehydrogenase. (b) Relative fluorescence unit (RFU) readings after additionally using glycolate oxidase in the glycolic acid assay. Milli-Q water was used as a no-matrix control. The dotted line shows the limit of neat PG. Error bars show the standard deviations of two replicates. Ordinary one-way ANOVA with Dunnett’s multiple comparison. ns, not significant; *p < 0.05; **p < 0.01; ****p < 0.0001.