Glucosinolates (Cruciferous Extract).

Glucoraphanin is the storage form and sulforaphane is what myrosinase releases from it. A formula carrying both supplies the finished isothiocyanate plus a reserve that converts over time.

Converting glucosinolates to isothiocyanates needs myrosinase, and intact sprout material is the usual source of that enzyme. Without it the conversion falls back on gut bacteria and yields much less.

Glucobrassicin breaks down to indole-3-carbinol, which condenses in stomach acid to diindolylmethane. Supplying DIM covers the same endpoint the glucosinolate reaches through two steps.

Sinigrin is the glucosinolate that myrosinase converts to allyl isothiocyanate, so the pair is the same molecule before and after hydrolysis.

Ascorbate is a cofactor for myrosinase and pushes hydrolysis toward isothiocyanates rather than nitriles, raising the usable yield from the same glucosinolate load.

Glucosinolate breakdown yields thiocyanate ions that compete with iodide at the sodium-iodide symporter and lower iodide uptake into the thyroid. A high glucosinolate load raises the iodine intake that should sit alongside it.

Thiocyanate from glucosinolate hydrolysis competes with kelp-sourced iodide at the same symporter, so the two pull against each other at that transport step.

Isothiocyanates react quickly with free thiols to form dithiocarbamates, so N-acetylcysteine dosed alongside binds a share of the released isothiocyanate and lowers what stays free.

Released isothiocyanates are conjugated to glutathione by glutathione S-transferases and exported through the mercapturic acid route. Glutathione supply sets the pace of that handling step.

Aliphatic glucosinolates are built from chain-elongated methionine, so methionine is the amino acid backbone of that family.

Indole glucosinolates such as glucobrassicin derive from tryptophan, which is why brassica material carries indole forms alongside aliphatic ones.

Aromatic glucosinolates such as gluconasturtiin are built from phenylalanine, the route behind phenethyl isothiocyanate in watercress-type material.

Each glucosinolate carries two sulfur atoms, one in the thioglucose link and one in the sulfate group, so sulfate supply limits how much can be formed.

Selenate and sulfate share assimilation and transport machinery in brassica tissue, so selenium enrichment and a high glucosinolate load draw on the same route and trade off.

Selenium-enriched mustard accumulates selenium through the sulfate route that also feeds glucosinolate formation, so the same material cannot maximise both at once.

Epithiospecifier protein needs ferrous iron to divert glucosinolate hydrolysis toward nitriles rather than isothiocyanates, so iron-rich conditions lower the isothiocyanate share.

Watercress is the standard source of gluconasturtiin and its phenethyl isothiocyanate, widening the profile beyond broccoli-type aliphatic forms.

Rocket seed supplies both glucosinolates and a high myrosinase load, so substrate and converting enzyme arrive in the same material.

Moringa carries glucomoringin, a rhamnose-substituted glucosinolate with its own isothiocyanate, adding a distinct member of the same family.

Isothiocyanates raise conjugating enzyme expression while glucarate slows the beta-glucuronidase step that undoes glucuronide conjugation, so the two act at opposite ends of the same sequence.

Glucosinolates are inert storage compounds until the thioglucosidase myrosinase cleaves them into isothiocyanates. Cooking or extract processing destroys plant myrosinase, and a product supplying active enzyme restores the conversion step. Enzyme-active and enzyme-free preparations therefore behave differently even at identical glucosinolate content.

When plant myrosinase is absent, colonic bacteria carry out the hydrolysis instead, and human conversion rates vary several-fold between individuals with different microbiota. Supplying bacterial species with thioglucosidase activity is the rationale for pairing. Which specific strains matter in people is not settled.

Certain Lactobacillus plantarum strains hydrolyse glucosinolates to isothiocyanates in culture, which is why the species turns up in fermented brassica products. Strain matters a great deal and the effect does not generalise across the species. The evidence is laboratory and food-fermentation work, not human conversion trials.

Colonic Bifidobacterium contributes to the general fermentative environment where glucosinolate hydrolysis occurs after plant myrosinase has been lost. The link is to the community rather than to a characterised enzyme in this species. Read it as ecological support, not a direct conversion claim.

Since a large share of glucosinolate conversion in humans happens in the colon, the state of the resident microbiota is part of the dose that actually gets delivered. Inulin is a fermentable substrate that shifts that community. The mechanism is indirect and the size of any effect on isothiocyanate yield in people is not established.

Isothiocyanates derived from glucosinolates modify Keap1 cysteines and release Nrf2, which switches on phase II conjugating enzymes. Quercetin engages the same transcriptional programme through a different chemistry. Combined induction is described in cell work, and enzyme induction is a marker rather than a clinical outcome.

Alpha-lipoic acid is a dithiol that also engages Nrf2-driven phase II induction, the same node isothiocyanates hit. The two are chemically unrelated but converge on one transcription factor. Evidence sits at the cell and marker level.

EGCG and isothiocyanates both raise glutathione S-transferase and NAD(P)H quinone oxidoreductase activity in cultured cells. Formulators pair them for that reason. Enzyme activity is a marker and its translation to a health outcome is not established in this pairing.

Curcumin is a Michael acceptor that reacts with reactive cysteines much as isothiocyanates do, and the two induce overlapping detoxification enzymes in vitro. The pairing is common in detoxification-positioned formulas. The overlap can also mean redundancy rather than addition.

Isothiocyanates are conjugated to glutathione, then processed down the mercapturic acid pathway to cysteine conjugates and N-acetylcysteine conjugates that appear in urine. Cysteine availability is what limits glutathione synthesis. The conjugation route is textbook; whether extra cysteine changes isothiocyanate handling in people has not been shown.

Taurine sits downstream of cysteine in sulfur amino acid metabolism, the same pool that supplies glutathione for isothiocyanate conjugation. The connection is to a shared substrate pool rather than a direct interaction. Read it as metabolic context, not a measured pairing.

Silymarin is used in the same detoxification-positioned formulas and also raises glutathione-linked enzyme activity in preclinical work. The pairing is conventional and mechanistically plausible. No combination study in humans supports it.

Sulfite oxidase, a molybdenum-dependent enzyme, handles the sulfite generated when sulfur-containing compounds are catabolised. A diet loaded with sulfur-rich brassica constituents runs that enzyme harder. The cofactor requirement is settled; no trial has tested whether extra molybdenum matters at ordinary intakes.

Glutathione reductase is an FAD-dependent flavoenzyme, and it regenerates the reduced glutathione that isothiocyanate conjugation consumes. Riboflavin is the source of that FAD. The cofactor link is textbook biochemistry rather than a tested combination.