Exogenous myrosinase from mustard seed increases bioavailability of sulforaphane from a glucoraphanin-rich broccoli seed extract in a randomized clinical study.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 41692762 · doi:10.1038/s41598-026-39389-4
What was done
In a randomized, double-blind, crossover study, 16 subjects (9 females, 7 males) received a single oral dose of glucoraphanin (GR) from broccoli seed extract either combined with myrosinase-containing mustard seed powder or alone (both formulations administered with ascorbic acid). The primary outcomes were urinary metabolite measurements to assess sulforaphane (SF) bioavailability and early (first 8 hours) conversion rate, along with analysis of fecal bacterial communities and GR-converting genes.
What was found
Co-administration of mustard seed myrosinase with glucoraphanin (GR + Myr) doubled the bioavailability of SF compared to GR alone (39.8 ± 3.1% vs 18.6 ± 3.1%). The conversion rate in the first 8 hours was higher with GR + Myr than with GR alone (25.4% ± 2.7% vs 8.0% ± 2.7%). A single dose produced no differences in fecal bacterial communities, but four bacterial GR-converting genes correlated significantly with GR conversion (p < 0.0155).
Why it matters
Glucoraphanin requires enzymatic conversion to produce bioactive sulforaphane, which is otherwise reliant on variable gut microbial activity. This study shows that pairing broccoli seed extract with a plant-derived myrosinase source substantially increases both the speed and overall yield of sulforaphane bioavailability in humans.
Limits
The study is limited by a small sample size of 16 participants and a single-dose exposure design, meaning sustained pharmacokinetic effects, safety, and clinical outcomes were not evaluated.
Cited by
- partial The majority of the conversion of glucoraphanin to sulforaphane is performed by gut bacteria in the colon.