(1) bubble para-enriched hydrogen gas into the precursor solution to produce hyperpolarized fumarate; (2) pneumatically shuttle the sample into an NMR tube containing fumarase in D2O held in an 11.7 T magnet; (3) apply either OPE-45, OPE-s90, or a 45° pulse every 4 s and detect the resulting NMR signal. The results are shown in Fig. . Each pulse sequence destroys most or all of the hyperpolarized spin order in malate-D2 with each application, but the singlet order for fumarate molecules is unaffected. We observe persistent NMR signals for ~1 minute, which is possible because new molecules of malate-D2 form between the application of each pulse sequence. The water signal is significantly attenuated in the OPE-45 spectra, and virtually absent from the OPE-s90 spectra.