Sinigrine

Sinigrin is a mustard oil glycoside that belongs to the glucosinolate family allyl isothiocyanate (AITC) and is found in plants of the Brassicaceae family, such as broccoli and Brussels sprouts, in the seeds of Brassica nigra (mustard seeds contain large amounts of sinigrin) as well as in horseradish and in Raphanie sativi radix, the black radish root.

Sinigrin is converted to allyl isothiocyanate by the action of β-sulphoglucosidase, myrosinase (myrosinase is stored elsewhere in the plant cell), splitting off glucose. Released allyl isothiocyanate is the carrier of the pungent taste. Allyl isothiocyanate, together with other substances of the glucosinolate family, is part of a sophisticated defense system that plants have developed over several hundred million years of evolution to protect themselves from parasitic attacks by aphids, ticks, bacteria or nematodes (Melrose J 2019; Bhattacharya A et al. 2010).
Allyl isothiocyanate is also used therapeutically as allyl mustard oil. However, the substance is not stable in the long term and is further degraded in aqueous media, including to allylamine, which irritates the skin and eyes. Allyl isothiocyanate released in the mouth also causes pungency in the throat and nose.

AITC is as effective as vancomycin in treating bacteria classified by the WHO as antibiotic-resistant "priority pathogens" and also has oncological effects through the induction of phase II antioxidant enzymes that inactivate potential carcinogens.

Glucosinolates may be useful in the treatment of biofilms formed on medical implants and catheters by problematic pathogenic bacteria such as Pseudomonas aeruginosa and Staphylococcus aureus, and are effective antimicrobial agents against a number of clinically important bacteria and fungi.

Glucosinolates are also used to prevent bacterial and fungal spoilage of foods in modern atmospheric packaging technology, improving the shelf life of these products (Melrose J (2019)

1. Bhattacharya A et al. (2010) Allyl isothiocyanate-rich mustard seed powder inhibits bladder cancer growth and muscle invasion. Carcinogenesis 31:2105-2110.
2. Melrose J (2019) The Glucosinolates: A Sulphur Glucoside Family of Mustard Anti-Tumour and Antimicrobial Phytochemicals of Potential Therapeutic Application. Biomedicines 7:62.
3. Nair AB et al. 82020) Development of HPLC Method for Quantification of Sinigrin from Raphanus sativus Roots and Evaluation of Its Anticancer Potential. Molecules 25: 4947.