Blog

The large plant family of brassicales or BRASSICACEAE(formerly cruciferous) includes the genus raphanus (mainly the various radishes and wild radish (Raphanus raphanistrum) and other genera also interesting because they include useful and medicinal plants, examples: the numerous species of cabbage-turnip-mustard-rapeseed-Chinese cabbage (brassica), watercress (nasturtium), horseradish (armoracia), white mustard (sinapis)….

These plants with tuberous roots are characterized by their flowers with 4 free petals in the shape of a cross, and the majority of brassicales contain glucosinolates, a family of chemical compounds, which enzymatically transform into thiocyanates and isothiocyanates, pharmacologically active molecules with a spicy taste.

Radishes are plants that have been cultivated for a long time in Eurasia for their tuberous roots; we do not really know the original wild plant.

There are many varieties which differ in the appearance of the root (edible) and foliage, their nutritional value, their adaptation to different climates, and the secondary compounds they contain (glucosinolates, phenolic compounds, seed oil) .

The PINK RED RADISH or EUROPEAN RADISH (RAPHAHUS SATIVUS var SATIVUS) can be grown in many climates and is small.

The WHITE RADISH or DAIKON (RAPHAHUS SATIVUS,var ACANTHIFORMIS or LONGIPINNATUS)

The BLACK RADISH (RAPHAHUS SATIVUS var NIGER)

Black and white radishes can have a medium to large elongated root, they are difficult to grow in tropical regions (except at altitude).

Radishes differ in appearance, color of the skin and size of their roots but their flesh is generally very white.

Tuberous radish roots are eaten raw or cooked ; they are very popular in Asia (China, Korea, Japan).

Radishes are grown in the majority of countries in temperate and subtropical zones.

The edible and medicinal parts are: the root, root juice, foliage, oilseeds.

RADISH BLACK WHITE DAIKON VEGETABLE DIETARY MEDICINAL INSUFFICIENCY OF BILIARY SECRETION DIGESTIVE MIGRAINE CONSTIPATION COMMON RESPIRATORY INFECTION CANCER PREVENTION DIABETES BLOOD LIPIDS ABNORMALITIES

CHEMICAL COMPOSITION AND PROPERTIES

RADISH ROOTS

Radish roots contain:

• 90 to 95% water,
• soluble and insoluble fibers (1 to 3%), the percentage of which increases as the radish becomes more fibrous,
• abundant mineral salts: notably potassium ( 250 mg per 100g of raw root), but also salts of calcium, sodium, magnesium, phosphorus, copper, iron, selenenium, iodine… in varying quantities depending on the quality of the soil and growing conditions,
• phenolic substances in small quantities: phenolic acids, flavonoids, plant dyes for red-colored varieties (pelargonidin and cyanidin),
• vitamin C, vitamin A and provitamin A (beta carotene), group B vitamins,
• and GLUCOSINOLATES (eg: glucoraphasatin, glucorapanin, glucobrassicin), these sulfur compounds are hydrolyzed by an enzyme present in the radish (myrosinase), when the root is cut or crushed.

This enzymatic reaction releases compounds which have a strong odor and a very spicy taste, a little burning for the respiratory (nose) or digestive (mouth, stomach) mucous membranes.
The compounds thus released are ISOTHIOCYANATES which have interesting pharmacological properties.
The myrosinase enzyme is destroyed by cooking.
Glucosinolates are also partly hydrolyzed in the colon into isothiocyanates by the intestinal flora.

The quantity of glucosinolates and therefore releasable isothiocyanates varies depending on the variety of radish and the growing conditions (humidity, heat):

• Small PINK RADISHES contain little, especially when they are young; as they age they become spicier and more fibrous.
• The large roots of BLACK RADISH contain much more, they are very spicy, a little burning for the mucous membranes.
• White or DAIKON radishes contain less than black radishes, their flesh is more juicy and less firm than that of black radishes, but this varies greatly depending on the variety.

Isothiocyanates have medicinal properties:

• GASTROPROTECTOR: their spicy flavor promotes the secretion of mucus in the stomach, thus protecting the gastric mucosa and giving appetite,
• RESPIRATORY DECONGESTANT: they have an anti-allergic effect, decongestant of the respiratory mucous membranes (nose, sinuses, bronchi ), antitussive and thinning of bronchial secretions,
• CHOLAGOGUE AND CHOLERETIC: there is an increase in hepatic secretion of bile and excretion of bile into the intestine, reduction in the number and reduction in the size of gallbladder stones,
• ACTION ON CHOLESTEROL: the increase in the secretion and excretion of bile salts promotes an overall reduction in blood and intrahepatic cholesterol,
• ACTION ON URINARY STONES (urolithiasis): probable action to reduce the size of urinary stones (uric stones),
• ANTI-CANCER: in vitro studies suggest an anti-cancer effect with probably a possible reduction in colon and rectal cancers,
• ANTI-OXIDANTS: the combination of glucosinolates, their isothiocyanate derivatives and flavonoids present in radish counteracts the action of free radicals and interacts with the inflammatory reaction.

RADISH LEAVES

Radish leaves can be eaten raw or cooked:

• raw they provide vitamins (A, C and B), mineral salts and spicy glucosinolates or isothiocyanates if the leaves are crushed or finely cut,
• lightly cooked in soups or accompaniment to vegetables, they lose their spicy side and we can consume a larger quantity: soluble and insoluble fibers, protective phenolic substances more abundant than in the root, vitamin A and provitamin A, abundant mineral salts.

RADISH SEEDS

Radish seeds are oilseed; they contain an oil which is not considered edible (because of the significant presence of erucic acid).
average composition of the main fatty acids:
alpha-linolenic acid (tri unsaturated) (52–55%),
erucic acid (mono unsaturated) (30–33%),
and palmitic acid (saturated) (20–22%).

These seeds are interesting because they are easy to germinate.
The sprouted seed contains vitamins, glucosinolates, mineral salts, the slightly « spicy » taste of the radish sprout enhances the blandness of a dish or a vegetable salad and promotes appetite.
An animal study shows that crushed radish seeds regulate intestinal transit by probably acting on the secretion of gastrointestinal hormones and proteins which act on intestinal mobility.

RADISH DEFENSINS

Defensins are low molecular weight proteins secreted by plants and animals to fight infections. Radish defensin called RsAFP2 is a peptide that helps fight Candida albicans fungal infection.
This defensin prevents or delays the production of a biofilm by yeasts. The biofilm encapsulates and protects the yeast-fungus against the action of antibiotics.
There is therefore potential synergy of action between defensin and antifungal antibiotics.

USES

RADISH, EDIBLE AND DIETETIC PLANT

Small fresh pink-red radishes are excellent vegetables with or without their leaves, they provide vitamins, glucosinolates in small quantities, mineral salts (especially potassium) and protective phenolic compounds.
Eaten as a starter, pink radishes whet the appetite and promote digestion.

Black radish contains much more glucosinolates and therefore isothiocyanates, it is used raw sparingly, it can also be eaten cooked.

White radish or DAIKON is still little known in Europe but widely used in Asian cuisine, raw, cooked, dried or fermented.

Radish seeds are easy to germinate, sprouted seeds are dietary.

BLACK RADISH MEDICINAL VEGETABLE

Black radish is considered a MEDICINAL ROOT VEGETABLE:

• As a liver protectant,
• for its cholagogue and choleretic properties (activation of secretion by the liver and excretion of bile) limiting the formation of gallstones,
• this increase bile excretion helps reduce blood lipid levels and regularize intestinal transit which is accelerated: fight against constipation, improvement of type 2 diabetes, reduction of atherosclerotic plaques in the blood vessels, better digestion,
• the consumption of black radish acts positively on the microbiome of the intestine (microbial flora of the colon): improvement of metabolic syndrome linked to overweight and associated digestive disorders,
• volatile isothiocyanates act on the respiratory mucosa: anti-allergic effect, can be antibacterial, decongestant and facilitate expectoration,
• several laboratory studies on cancer cell cultures show that black radish extracts promote apoptosis (cell death) of certain cancer lines,
• increase in diuresis (urine ) and protection against uric acid stones.

MAIN INDICATIONS

• Difficult digestion due to insufficient bile secretion, digestive migraines, anorexia (lack of appetite), chronic constipation, prevention of colon cancer,
• chronic bronchitis without fever, wet cough, sinusitis,
• type 2 diabetes, overweight and increased blood lipids,
• skin disorders linked to poor digestion: certain eczemas, acne

EXAMPLES OF DOSAGE
If you do not have fresh black radish, you can find many specialties in pharmacies containing black radish extracts: powder capsules, juice ampoule, alcoholic tincture.
Comply with laboratory instructions because these phytomedicines or food supplements have varied compositions of active ingredients.
For the black radish tincture which is standardized: 30 to 60 drops per day in two doses.

BLACK RADISH SYRUP

This is a classic preparation of black radish in Western medicine to calm a common respiratory tract infection, it is done « at home ».
Stack thin slices of black radish in a glass container, interspersing a little sugar between them.
Over the hours, the sugar absorbs the radish « juice » and after 24 hours we filter everything to collect the radish syrup. This syrup can be kept in the cold for a few days.
Dosage: 3 to 4 teaspoons per day and half dose for children, suspend treatment in case of digestive disorders (heartburn).

PRECAUTIONS AND CONTRAINDICATIONS

• Black radish extracts are contraindicated when the gallbladder contains gallstones (gallstones) because the increased flow of bile and contractions of the gallbladder could send these small stones into the common bile duct and increase the risk of an attack of hepatic colic due to blockage of the bile ducts,
• some people are allergic to isothiocyanates,
• others with fragile stomachs cannot tolerate black radishes, or pink or white radishes that are too « spicy »,
• the compounds Sulfur from black radish can modify the metabolism of the thyroid when consumed in large quantities,
• black radish extracts are therefore contraindicated in people with an abnormal functioning of the thyroid (hypo or hyperthyroidism)
• isothiocyanates are active compounds: It is best to avoid black radish or its extracts when you are pregnant or breastfeeding.

CULTIVATION OF RADISHES.

Pink radishes are very easy to grow, they are often the first vegetable that children grow.
The seeds are sown in place in fine weather in light or sandy soil that is regularly moistened; the harvest can be done 3 to 5 weeks later depending on the local climate.
There are many varieties of crops available in seed stores.

Black radishes are sown in summer in very loose, moist soil. They can be harvested in the fall or left in the ground until the first frost. Once dug up, they are stored in a silo like carrots.
You can also cut them into strips and dry them.

White radishes (sometimes a little colored), daikon or Chinese radishes are grown in the same way as black radishes; they are a vegetable plant that is harvested in the fall and in winter, they are often preserved dried in Asia.

SUMMARY

RADISHES, DIETARY AND MEDICINAL ROOT VEGETABLES
Pink, white or black radishes are very easy to grow vegetables that can be eaten raw or cooked.
They contain sulfur compounds which after enzymatic reaction are transformed into isothiocyanates with a spicy flavor.
These compounds have interesting medicinal properties, mainly: protection of the liver, increase in bile flow, regularization of bowel movements, action on inflamed respiratory tract, probable reduction in the risk of colon cancer

Copyright 2024 : Dr Jean-Michel Hurtel

You are on www.phytomania.com
French site dedicated to medicinal plants and essential oils
PHYTOTHERAPY, AROMATHERAPY, MEDICINAL PLANTS, ESSENTIAL OILS