Food as medicine, broccoli, bioactive compounds, glucosinolates, isothiocyanates, glucoraphanin, glucobrassicin, sulforaphane, diindolylmethane, antioxidant, anti-inflammatory, anticancer, anti-diabetic, meta-analysis.

1. VEGETABLE AS MEDICINE:
BROCCOLI,
BRASSICA OLERACEA VAR. ITALICA
By
Kevin KF Ng, MD PhD.
Former Associate Professor of Medicine
Division of Clinical Pharmacology
University of Miami, Miami, FL., USA
Email: kevinng68@gmail.com
A slide presentation for HealthCare Providers June 2020

2. America's favorite vegetable is broccoli (2018)
open-ended survey from April 20 to May 4 of 2018 that polled nearly
4,000 Americans across the nation
https://www.foxnews.com/food-drink/americas-favorite-vegetable-is-broccoli-survey-says

3. Outline of Lecture
▪ Broccoli: origin, US production
▪ Scientific classification
▪ Anatomy and varieties
▪ Nutrient composition
▪ Bioactive compounds
▪ Bioavailability of glucosinolates
▪ Pharmacological properties
▪ Meta-analysis of clinical studies
▪ Summary

4. Origin of Broccoli
▪ Broccoli, botanically known as Brassica oleracea italica, is
native to the Mediterranean
▪ It is a human invention that was bred by Italian farmers
more than 2,000 years ago.
▪ The word broccoli comes from the Italian plural of broccolo,
which means "the flowering crest of a cabbage.“
▪ It was introduced to England and America in the 1700s

5. Top Broccoli and Cauliflower Production Countries
http://chartsbin.com/view/39898

6. Scientific classification of Broccoli

7. Some examples of species of Brassica oleracea
https://www.semanticscholar.org/paper/Glucosinolates-and-isothiocyanates-from-
broccoli-Shimoda-Hirano/6d4a5155ec2cdf9aceed4a924b89d111b6d18414

8. Number of publications on “Broccoli” in PubMed from
1929 to 2019
https://www.ncbi.nlm.nih.gov/pubmed/?term=Broccoli
Total 20,185

9. Anatomy of Broccoli
https://ohioline.osu.edu/factsheet/hyg-1605

10. Varieties of Broccoli

11. Nutrient composition of 100 g of raw broccoli
https://fdc.nal.usda.gov/fdc-app.html#/food-details/747447/nutrients

12. Nutrient and phytochemical compositions of
100 g of raw broccoli
https://fdc.nal.usda.gov/fdc-app.html#/food-details/747447/nutrients

13. What are phytochemicals?
▪ Phytochemicals are bioactive chemical compounds
produced by plants.
▪ They help plants to thrive or defend against competitors,
predators, or pathogens.
▪ Some phytochemicals are used as poisons and others as
traditional medicine.
▪ The examples of phytochemicals in broccoli are:
▪ carotenoids
▪ phenolics
▪ glucosinolates
▪ Phytochemicals are not essential nutrients but are
beneficial for human health.
Most widely studied

14. Phytochemicals are secondary metabolites
https://www.intechopen.com/books/oxidative-stress-and-chronic-degenerative-diseases-a-role-
for-antioxidants/food-phenolic-compounds-main-classes-sources-and-their-antioxidant-power
Glucosinolates

15. Chemical structure of glucosinolate
••
•
•
•
•
•
• R: Aliphatic, Aromatic, Indole
glucosinolate

16. Glucosinolates and Respective Derivatives (Isothiocyanates)
https://link.springer.com/chapter/10.1007/978-3-319-51639-4_1

17. Concentrations of glucosinolates in the florets of
8 reference broccoli cultivars (two commercial cultivars and six trial cultivars)
grown in the field. •
https://journals.ashs.org/jashs/view/journals/jashs/139/4/article-p460.xml
•
•

18. Sulforaphane content in different Italian broccoli landraces
https://www.researchgate.net/figure/Sulforaphane-content-in-different-Italian-broccoli-landraces-conteudo-de-sulforafano-em_fig3_291014969

19. Classification of glucosinolates
about 130 glucosinolates have been identified
https://www.mdpi.com/1420-3049/23/6/1313/htm

20. Classification of glucosinolates
about 130 glucosinolates have been identified
https://www.mdpi.com/1420-3049/23/6/1313/htm
Diindolylmethane (DIM)

21. Effect of the enzyme (myrosinase) on glucosinulate
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6885086/

22. Effect of pH on specific activity of broccoli myrosinase
https://www.mdpi.com/1420-3049/23/6/1313/htm

23. Anticancer properties of isothiocyantes
▪ Modulation of phase I and II enzymes
▪ Inhibition of cell growth by causing cell
cycle arrest and inducing cell death
▪ Prevention of metastasis and
angiogenesis
▪ Regulation of the epigenetic machinery
https://www.mdpi.com/2076-3921/8/4/106/htm

24. Biological activities of major broccoli phytochemicals

25. Mechanisms of action of bioactive compounds in Brassicaceae.
https://www.iris.unina.it/retrieve/handle/11588/696754/156335/Raiola%20et%20al%202018.pdf

26. The formation of sulforaphane from glucoraphanin
https://www.researchgate.net/figure/The-myrosinase-reaction-and-
the-interconversion-of-sulforaphane-and-erucin-The_fig3_228104419

27. Physicochemical properties of sulforaphane
▪ Sulforaphane is a small molecule with a
▪ molecular weight of 177.28 g/mol
▪ molecular formula is C6H11NOS2
▪ melting point between 58.6 and 91.2 °C
▪ Although glucoraphanin is hydrophilic,
sulforaphane, like other isothiocyanates, is
typically an aliphatic lipophilic molecule.

28. Pharmacological actions of sulforaphane
▪ Antioxidant
▪ Antimicrobial
▪ Anti-inflammatory
▪ Anticancer
▪ Anti-diabetic

29. Anti-diabetic effect of sulforaphane: amylase inhibition assay
https://pdfs.semanticscholar.org/95c6/bbe8a2364cb915823c02fda9e44a70d14750.pdf
sulforaphane

30. Effects of highly concentrated SFN (sulforaphane) provided as BSE
(broccoli sprout extract) in T2D patients. (2017)
https://stm.sciencemag.org/content/9/394/eaah4477HOMA-IR = Homeostatic Model Assessment of Insulin Resistance

31. Anti-inflammatory effect of sulforaphane on NF-κB pathways and
antioxidant effect on Nrf2 pathway (2019)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6885086/
Activates Inhibits
Anti-inflammationAnti-oxidation

32. The formation of Indole-3-carbinol from glucobrassicin
https://www.researchgate.net/figure/Breakdown-of-glucosinolates-adapted-from-3_fig1_6489397

33. Formation of 3,3’-diindolymethane (DIM) from Indole-3-carbinol (I3C)
https://supplementsinreview.com/testosterone/diindolylmethane-dim-testosterone/
Inactive ActivePrecursor

34. Distribution of diindolylmethane (DIM) in tissues of a mouse.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5059820/

35. Indole-3-carbinol (I3C) and 3,3’-diindolylmethane (DIM)
regulate the expression of phase I metabolizing enzymes via AHR pathway
https://lpi.oregonstate.edu/book/export/html/500

36. Overview of DIM’s (Diindolylmethane’s) Anti-Cancer and
Immune Modulating Properties
https://www.diindolylmethane-dim.com/molecular_biology.htm#.XrdWdmhKiUk
Diindolylmethane

37. Diindolylmethane (DIM) In-Vivo Effect on Key
Immune Modulating Cytokines
https://www.diindolylmethane-dim.com/molecular_biology.htm#.XrdWdmhKiUk
G-CSF iL-12
iL-6 IFN-γ

38. In-Vivo Animal Study: DIM (diindolylmethane) Inhibits DMBA-induced
Mammary Tumor Growth
https://www.diindolylmethane-dim.com/molecular_biology.htm#.XrdWdmhKiUk

39. Fate of glucosinolates and their breakdown products
in the human gut.
https://www.frontiersin.org/articles/10.3389/fnut.2016.00024/full

40. Bioavailability and pharmacokinetic parameters of sulforaphane
following administration of dietary doses in rat
http://epubs.surrey.ac.uk/286622/3/Natalya-PK.pdf
•
•

41. Comparative bioavailability of phytochemicals commonly used
in dietary supplements (2019)
https://www.hindawi.com/journals/omcl/2019/2716870/

42. Effects of cooking on sulforaphane content in Broccolini
https://www.mdpi.com/2304-8158/8/7/257/htm

43. Health Benefits of Broccoli
▪ Packed with dietary fiber, vitamins, minerals and bioactive compounds
▪ Antioxidants: glucoraphane when converted to sulforaphane
▪ Anti-inflammatory: flavonoids e.g. kaempferol
▪ Immuno-modulatory: glucobrassicin when converted to diindolylemethane
▪ Anti-cancer activity in vitro:
▪ Breast
▪ Prostate
▪ Stomach
▪ Colon
▪ Kidney
▪ Bladder
▪ Anti-diabetic
▪ Anti-hyperlipidemia
https://www.healthline.com/nutrition/benefits-of-broccoli#section14

44. Meta-analysis of effects of broccoli on cancers

45. What is meta-analysis: evidence-based medicine
https://rdfeinman.files.wordpress.com/2015/08/meta-anal_whatis.png

46. Example of a Meta-analysis: Hierarchy of evidence in clinical studies
use of statistical methods to summarise the results of these studies.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3049418/
Example

47. Cruciferous vegetable consumption and lung cancer risk:
a systematic review (2009)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2735794/

48. Cruciferous vegetables intake reduced the risk of breast cancer:
A meta-analysis (2012)
https://www.thebreastonline.com/article/S0960-9776(12)00164-6/fulltext

49. Cruciferous Vegetables Intake Is Associated with
Lower Risk of Renal Cell Carcinoma:
Evidence from a Meta-Analysis of Observational Studies 2013
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0075732

50. Cruciferous vegetable consumption reduced the risk of
pancreatic cancer: a meta-analysis (2015)
https://wjso.biomedcentral.com/articles/10.1186/s12957-015-0454-4

51. Cruciferous vegetable consumption reduced colon cancer risk.
(2014)
http://projects.hsl.wisc.edu/SERVICE/champions/EFWH/articles/Day%202%20Modules%207-
13/Module%207/Tse,%20Cruciferous%20Vegetables%20and%20Risk%20of%20Colorectal%20Neoplasms%202014.pdf

52. Broccoli consumption reduced colorectal
neoplasm risk (2014)
http://projects.hsl.wisc.edu/SERVICE/champions/EFWH/articles/Day%202%20Modules%207-
13/Module%207/Tse,%20Cruciferous%20Vegetables%20and%20Risk%20of%20Colorectal%20Neoplasms%202014.pdf

53. Summary
▪ Broccoli originated in Italy and was introduced to America in the 1700s.
▪ Broccoli is America’s favorite vegetable in 2018.
▪ Besides macronutrients and micronutrients, broccoli is rich in
phytochemicals: carotenoids, phenolics and glucosinolates.
▪ The notable glucosinolates are glucoraphanin, glucobrasicin and their
active metabolites sulfurophane and diindolylmethane
▪ These bioactive compounds have been widely studied for the following
properties: antioxidant, anti-inflammation, anticancer, antidiabetic, and
anti-hyperlipidemia.
▪ Favorable results are seen in all clinical studies.

54. ANY QUESTION?
Please contact
Kevin KF Ng, MD, PhD
Email: kevinng68@gmail.com