Hyperpolarized fumarate can be used as a probe of real-time metabolism in vivo, using carbon-13 magnetic resonance imaging. Dissolution dynamic nuclear polarization is commonly used to produce hyperpolarized fumarate, but a cheaper and faster alternative is to produce hyperpolarized fumarate via PHIP (parahydrogen induced polarization). In this work we <i>trans</i>-hydrogenate [1-¹³C]acetylene dicarboxylate with <i>para</i>-enriched hydrogen using a commercially available Ru catalyst

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... in water to produce hyperpolarized [1-¹³C]fumarate. We show that fumarate is produced in 89% yield, with succinate as a side product in 11% yield. The proton polarization is converted into ¹³C magnetization using a constant adiabaticity field cycle, and a polarization level of 25% is achieved using 86% <i>para</i>-enriched hydrogen gas. We inject the hyperpolarized [1-¹³C]fumarate into cell suspensions and track the metabolism. This work opens the path to greatly accelerated preclinical studies using fumarate as a biomarker.