Figure 1.

The ¹³C NMR spectra of 50 mM GDCA, with 3.5 mM ¹³C-4 cholesterol, in the presence of coffee extracts (S1 and S3 coffee pods). The spectra were acquired with ¹H decoupling and NOE, in 10% D₂O aqueous solution, at 37 °C. The peak of ¹³C-4 enriched cholesterol appears at 44 ppm. Note that the relative area of this peak decreases in the presence of coffee extracts, particularly for the S3 coffee extract (insert graph).