CRUCIFEROUS VEGETABLES

by Dr. Lawrence Wilson

All information in this article is for educational purposes only. It is not for the diagnosis, treatment, prescription or cure of any health condition.

This important group of vegetables are so named because their flowers are shaped like a cross. The following has been excerpted from Wikipedia:

‪ Cruciferous vegetables are vegetables of the family Brassicaceae (also called Cruciferae). These vegetables are widely cultivated, with many genera, species, and cultivars being raised for food production such as cauliflower, cabbage, cress, bok choy, broccoli and similar green leaf vegetables. The family takes its alternate name (Cruciferae, New Latin for "cross-bearing") from the shape of their flowers, whose four petals resemble a cross.

Ten of the most common cruciferous vegetables eaten by people, known colloquially as cole crops,[1] are in a single species (B. oleracea); they are not distinguished from one another taxonomically, only by horticultural category of cultivar groups. Numerous other genera and species in the family are also edible. Cruciferous vegetables are one of the dominant food crops worldwide. They are high in vitamin C and soluble fiber and contain multiple nutrients and phytochemicals.

WHICH OF THE VEGETABLES ARE CRUCIFERS?

Extensive selective breeding has produced a large variety of cultivars, especially within the genus Brassica.

The taxonomy of common cruciferous vegetables

common name	genus	specific epithet	Cultivar Group
horseradish	Armoracia	rusticana
land cress	Barbarea	verna
ethiopian mustard	Brassica	carinata
kale	Brassica	oleracea	Acephala Group
collard greens	Brassica	oleracea	Acephala Group
Chinese broccoli (gai-lan)	Brassica	oleracea	Alboglabra Group
cabbage	Brassica	oleracea	Capitata Group
Brussels sprouts	Brassica	oleracea	Gemmifera Group
kohlrabi	Brassica	oleracea	Gongylodes Group
broccoli	Brassica	oleracea	Italica Group
broccoflower	Brassica	oleracea	Italica Group × Botrytis Group
broccoli romanesco	Brassica	oleracea	Botrytis Group / Italica Group
cauliflower	Brassica	oleracea	Botrytis Group
wild broccoli	Brassica	oleracea	Oleracea Group
bok choy	Brassica	rapa	chinensis
komatsuna	Brassica	rapa	pervidis or komatsuna
mizuna	Brassica	rapa	nipposinica
Rapini (broccoli rabe)	Brassica	rapa	parachinensis
flowering cabbage	Brassica	rapa	parachinensis
chinese cabbage, napa cabbage	Brassica	rapa	pekinensis
turnip root; greens	Brassica	rapa	rapifera
rutabaga	Brassica	napus	napobrassica
siberian kale	Brassica	napus	pabularia
canola/rapeseed	Brassica	rapa/napus	oleifera
wrapped heart mustard cabbage	Brassica	juncea	rugosa
mustard seeds, brown; greens	Brassica	juncea
mustard seeds, white	Brassica (or Sinapis)	hirta
mustard seeds, black	Brassica	nigra
tatsoi	Brassica	rosularis
arugula (rocket)	Eruca	vesicaria
field pepperweed	Lepidium	campestre
maca	Lepidium	meyenii
garden cress	Lepidium	sativum
watercress	Nasturtium	officinale
radish	Raphanus	sativus
daikon	Raphanus	sativus	longipinnatus
wasabi	Wasabia	japonica

Drug and toxin metabolism

Chemicals contained in cruciferous vegetables induce the expression of the liver enzyme CYP1A2.[2] Furthermore some drugs such as haloperidol and theophylline are metabolized by CYP1A2. Consequently consumption of cruciferous vegetable may decrease bioavailability and half-life of these drugs.[3]

Brassicaceae contain a number of hepato-protective agents.[4] Alliaceous and cruciferous vegetable consumption induces glutathione S-transferases, uridine diphosphate-glucuronosyl transferases, and quinone reductases[5] all of which participate in detoxification of carcinogens such as aflatoxin.[6]

Antimicrobial activity

Iso-thio-cyanates are an important factor in the action of wasabi against Helicobacter Pylori,[7][8][9] and ITC is not a molecule, but a functional group of many different molecules, Sinigrin being a notable precursor of allyl-ITC, and AITC being a larger part of Wasabi than of most other Brassicaceae. Sulforaphane demonstrates anti-inflammatory effects on Helicobacter pylori-infected gastric mucosae in mice and human subjects.[10]

Taste

People who can taste phenylthiocarbamide, which is either very bitter or tasteless, are less likely to eat cruciferous vegetables,[11] due to the resemblance between isothiocyanate (ITC) and PTC.

Contraindications (if raw)- Goiter

Raw cruciferous vegetables can potentially be goitrogenic (inducing goiter formation). They contain enzymes that interfere with the formation of thyroid hormone in people with iodine deficiency.[12][13]

Cooking for 30 minutes significantly reduces the amount of goitrogens and nitriles. At high intake of crucifers, the goitrogens inhibit the incorporation of iodine into thyroid hormone and also the transfer of iodine into milk by the mammary gland.[14]

References

1. http://www.botgard.ucla.edu/html/botanytextbooks/economicbotany/Brassica/index.html

2. Lampe JW, King IB, Li S, Grate MT, Barale KV, Chen C, Feng Z, Potter JD (June 2000). "Brassica vegetables increase and apiaceous vegetables decrease cytochrome P450 1A2 activity in humans: changes in caffeine metabolite ratios in response to controlled vegetable diets". Carcinogenesis 21 (6): 1157–62. doi:10.1093/carcin/21.6.1157. PMID 10837004.

3. Bibi Z (2008). "Role of cytochrome P450 in drug interactions". Nutr Metab (Lond) 5: 27. doi:10.1186/1743-7075-5-27. PMC 2584094. PMID 18928560.

4. Aggarwal BB, Ichikawa H (September 2005). "Molecular targets and anticancer potential of indole-3-carbinol and its derivatives". Cell Cycle 4 (9): 1201–15. doi:10.4161/cc.4.9.1993. PMID 16082211.

5. Kensler TW, Curphey TJ, Maxiutenko Y, Roebuck BD (2000). "Chemoprotection by organosulfur inducers of phase 2 enzymes: dithiolethiones and dithiins". Drug Metabol Drug Interact 17 (1-4): 3–22. doi:10.1515/DMDI.2000.17.1-4.3. PMID 11201301.

6. Kensler TW, Chen JG, Egner PA, Fahey JW, Jacobson LP, Stephenson KK, Ye L, Coady JL, Wang JB, Wu Y, Sun Y, Zhang QN, Zhang BC, Zhu YR, Qian GS, Carmella SG, Hecht SS, Benning L, Gange SJ, Groopman JD, Talalay P (November 2005). "Effects of glucosinolate-rich broccoli sprouts on urinary levels of aflatoxin-DNA adducts and phenanthrene tetraols in a randomized clinical trial in He Zuo township, Qidong, People's Republic of China". Cancer Epidemiol. Biomarkers Prev. 14 (11 Pt 1): 2605–13. doi:10.1158/1055-9965.EPI-05-0368. PMID 16284385.

7. Shin IS, Masuda H, Naohide K (August 2004). "Bactericidal activity of wasabi (Wasabia japonica) against Helicobacter pylori". Int. J. Food Microbiol. 94 (3): 255–61. doi:10.1016/S0168-1605(03)00297-6. PMID 15246236.

8. Haristoy X, Fahey JW, Scholtus I, Lozniewski A (April 2005). "Evaluation of the antimicrobial effects of several isothiocyanates on Helicobacter pylori". Planta Med. 71 (4): 326–30. doi:10.1055/s-2005-864098. PMID 15856408.

9. Fahey JW, Haristoy X, Dolan PM, Kensler TW, Scholtus I, Stephenson KK, Talalay P, Lozniewski A (May 2002). "Sulforaphane inhibits extracellular, intracellular, and antibiotic-resistant strains of Helicobacter pylori and prevents benzo[a]pyrene-induced stomach tumors". Proc. Natl. Acad. Sci. U.S.A. 99 (11): 7610–5. doi:10.1073/pnas.112203099. PMC 124299. PMID 12032331.

10. Yanaka A (2011). "Sulforaphane enhances protection and repair of gastric mucosa against oxidative stress in vitro, and demonstrates anti-inflammatory effects on Helicobacter pylori-infected gastric mucosae in mice and human subjects". Curr. Pharm. Des. 17 (16): 1532–40. doi:10.2174/138161211796196945. PMID 21548875.

11. Wooding S, Kim UK, Bamshad MJ, Larsen J, Jorde LB, Drayna D (April 2004). "Natural selection and molecular evolution in PTC, a bitter-taste receptor gene". Am. J. Hum. Genet. 74 (4): 637–46. doi:10.1086/383092. PMC 1181941. PMID 14997422. Lay summary – Science Blog.

12. Shomon M (August 27, 2009). "What are Goitrogens and How Do they Affect the Thyroid?". Thyroid Disease. About.com.

13. McDougall J (December 2005). "Thyroid Deficiency Strikes One in Six". McDougall Newsletter 4 (12).

14. Masterjohn C (15 February 2008). "Bearers of the Cross: Crucifers in the Context of Traditional Diets and Modern Science". The Weston A. Price Foundation for Wise Traditions in Food, Farming, and the Healing Arts.