# Percy Julian

*Percy Julian turned plant chemistry into life-saving medicines and industrial steroids, making once-expensive compounds affordable and forcing American science to reckon with Black authorship in a field built to exclude it.*

> Black's Encyclopedia — the sourced record of Black American life.
> Portal: Science & Invention · Status: In review · Revised: July 21, 2026 · Revisions: 1
> Canonical: https://www.blacksencyclopedia.com/record/percy-julian

## Questions this record answers

- Who was Percy Julian?
- Did Percy Julian make steroids affordable?
- What did Percy Julian invent or synthesize?
- How did Percy Julian shape modern medicinal chemistry?

## Summary

Percy Julian transformed plant sterols into practical medicines, helping make steroids and other costly compounds affordable to produce at scale. His work in synthetic organic chemistry made him one of the central architects of modern steroid chemistry.

## The archive's standing

Percy Julian stands as a major American chemist whose laboratory work changed how medicine was made. He did not merely participate in the field; he redirected it toward large-scale synthesis from plant sources, a move that widened access to drugs that had once been scarce and expensive. The archive holds him as an author of modern medicinal chemistry and a decisive Black scientific pioneer.

## Chemistry

Julian’s core achievement was synthetic organic chemistry, especially the conversion of plant sterols into valuable medicinal compounds. Sources credit him as a pioneer in the large-scale synthesis of human hormones such as progesterone and testosterone from plant sterols including stigmasterol and sitosterol, and as the first to synthesize physostigmine.

## Scale and access

His importance lies not only in isolated laboratory success but in industrial method. By showing how to produce important drugs from abundant plant sources, Julian helped lower costs and expand supply, which made these medicines more accessible to ordinary people and to the pharmaceutical industry.

## Black scientific authorship

Julian’s career also matters because it enlarges the record of Black scientific authorship in a profession structured by exclusion. A Black chemist born in 1899, he rose to national scientific distinction and became the second Black member elected to the National Academy of Sciences, evidence of the level of mastery his work reached even under systemic racism.

## Public memory

The public often remembers Julian through the hardships surrounding his career, but the archive places the emphasis on what he made. His legacy is not damage endured; it is chemistry made usable, mass-produced, and socially consequential. The home firebombing and other attacks belong in the record as acts done against a scientist whose work had already changed the field, not as the core of his identity.

## Sources

1. Evelyn B. Kellogg and William H. H. Lough, "Percy Lavon Julian," Science History Institute, Scientific Biographies, accessed July 18, 2026.
2. Jeffrey T. Borgan et al., "Percy Lavon Julian: A man who rose to every occasion," Proceedings of the American Philosophical Society / PMC full text, 2022.
3. Harvard University Department of Chemistry and Chemical Biology, "Cortinsone: Percy Lavon Julian, A.M. '23," 2023.
4. Encyclopedia.com, "Percy Lavon Julian 1899–1975," Encyclopedia of World Biography / Gale reference entry, accessed July 18, 2026.
5. "Percy Lavon Julian: A man who rose to every occasion," PMC article noting Julian as first Black chemist and second Black member elected to the National Academy of Sciences, 2022.

## Related records

- https://www.blacksencyclopedia.com/record/steroid-chemistry
- https://www.blacksencyclopedia.com/record/physostigmine
- https://www.blacksencyclopedia.com/record/cortisone
- https://www.blacksencyclopedia.com/record/progesterone
- https://www.blacksencyclopedia.com/record/testosterone

---

Cite as: Black's Encyclopedia, "Percy Julian," revised July 21, 2026. https://www.blacksencyclopedia.com/record/percy-julian

Text under the Black's Record License: cite the record, keep attribution attached, cite the revision date.