Rutaceae include about 130 genera and more than 1500 species of trees or shrubs mainly from warm regions.
The leaves of rutaceae are often punctuated with small vesicular inclusions containing aromatic compounds (essential oil).
The most important of the genera is Citrus; they are generally small trees with hardwood, often thorny trunk and branches, and leaves with a "winged" petiole.
The fruit is a complex berry (an hesperidium) whose colored envelope (from green to orange) contains many essential oil glands.
It contains an often edible pulp formed of succulent "hairs" wrapped in a spongy, fibrous and white tissue, the mesocarp.
Seeds in varying numbers, white or green, may be absent in some cultivated varieties.
This botanical genus (citrus) includes:
* wild species whose fruit pulp is generally inedible (it contains essential oil) and the leaf petiole is very often much more "winged" than that of cultivated species (example: Citrus macroptera from New Caledonia) ,
* cultivated species with less acid pulp and without inclusion of essential oil.
Botanists find it very difficult to classify Citrus species because these species are often hybrids and continue to hybridize including with wild species.
The most important fruits are: lemon, lime, orange, grapefruit, tangerine, pomelo.
Citrus aurantium, the bitter orange or sour orange and Citrus sinensis, the sweet orange, are closely related, both native to South Asia.
Citrus sinensis, the common or sweet orange tree is not a wild species but an hybrid which has many cultural varieties (example: valence orange, blood orange, "navel" orange); note that tropical varieties remain green even when ripe.
The bitter orange tree has been known in Europe since the 11th century, the sweet orange tree since the 15th (it was introduced into the new world by Christopher Columbus on his second trip!).
The bitter orange tree was therefore the first used in European medicine; it is a very hardy species resistant to parasites whose fruit has a fairly irregular rind and whose pulp is not very dense, generally leaving a central part empty.
Bitter and sweet orange trees are medicinal trees by their fruits, flowers and leaves, sweet orange juice is dietetic.
CHEMICAL COMPOSITION AND PROPERTIES
Here is an average chemical composition valid for the pulp of the two types of oranges:
- 88% water,
- less than 1% of proteins and lipids,
- 8 to 12% of carbohydrates,
- vitamins B1, B2, PP,
- small amount of vitamin A
- and at least 40mg / 100g of vitamin C, so it is a fruit rich in vitamin C.
Organic acids are well represented (citric, malic), their quantity decreases when the orange becomes very ripe.
ORANGE PEEL = ZEST
The bitter flavor of the zest is due to the presence of essential oil and flavonoids (in the form of heterosides), some of which are characteristic of Citrus, let us mention: diosmin, naringosin, hesperidoside, rutoside, tangeretin, nobiletin.
The rinds of immature fruits contain a little more alkaloids than ripe fruits, the most important are: sinephrine and octopamine.
The rind of the fruit is rich in pectic matter.
These chemical compounds (citrus flavonoids) are considered to be good protectors of small blood vessels by a direct action of "toning" of the walls of the capillaries.
They also seem to be active on the veins but it is more disputed (varicose veins, hemorrhoids) .
Their anti-inflammatory and protective action on various tissues (including blood vessels) is also due to their ability to trap free radicals.
The most widely used citroflavonoid is hesperidin present in the majority of citrus peels (lemon, orange, grapefruit), in particular in the zest and membranes of orange and therefore in unfiltered orange juice.
Recent studies are interested in the pharmacological properties of flavonoids including those extracted from Citrus:
- for the regulation of adipocytes activity (cells which store lipids (fatty substances)) and the fight against obesity,
- for their anticancer properties (by an anti-viral or cell protection action),
- for their specific anti-viral properties (hepatitis),
- for their ability to modify the action of certain enzymes important in the absorption of drugs.
Immature fruits are used in oriental medicine.
Studies have shown that green fruit extract opposes hyperglycemia by inducing the secretion of insulin and glucagon. In vitro, the hydroalcoholic extract of green fruit is hepatoprotective while the aqueous extract is not.
ALKALOIDS: SYNEPHRINE AND OCTAMINE
These two natural plant substances have a chemical structure and properties similar to those of ephedrine.
These are nervous system stimulants that cause excitement, irritability, increased heart rate, increased blood pressure, and sleeplessness much like caffeine .
Some consider them to be “fat burners”, but recent studies show that their harmful side effects on health are greater than the temporary slimming effect they induce.
They are doping substances.
These alkaloids are present but in small quantities in orange juice (or grapefruit), but not enough to cause a doping effect or cause nervous disorders (unless you drink several liters of orange juice per day).
ORANGE ESSENTIAL OILS
THE DIFFERENT ESSENTIAL OILS EXTRACTED FROM ORANGE TREES
Several types of essential oil are extracted from orange trees:
* flowers of the bitter orange tree, Citrus aurantium, the essential oil of neroli,
* leaves and small branches of two orange trees (when pruning the trees), petitgrain essential oil,
* bitter orange zest, essential oil of Curacao,
* sweet orange zest, orange tree essential oil.
The essential oil of the zest is often obtained as a by-product in orange juice packaging factories.
ORANGE ZEST ESSENTIAL OIL
The essential oil of orange peels sweet and bitter varieties look similar and contain:
- almost exclusively monoterpenes including limonene (95 to 98%), pinene and myrcene (1 to 2%)
- and less than 1% of aldehydes which give the differences in fragrance to essential oils.
Orange essential oil:
- is slightly antiseptic,
- soothing and calming,
- it promotes digestion, gives appetite and increases the amount of mucus secreted in the stomach, thus protecting the gastric mucosa a little more against the risk of gatritis or ulcer.
PETIT GRAIN ESSENTIAL OIL (leaves and small branches)
Petitgrain essential oil contains many compounds but it is dominated mainly by linalyl acetate (about 50%) and linalool (20 to 25%).
It is an essential oil:
- especially interesting for its ability to calm, to find sleep,
- to reduce mild anxiety, neurovegetative disorders, digestive spasms,
- slightly antiseptic .
BITTER ORANGE BLOSSOM ESSENTIAL OIL OR NEROLI ESSENTIAL OIL
This very fragrant essential oil dominated by monoterpenes and linalool contains sesquiterpéols absent from other types of orange essential oils.
She acts :
- as a modulator of the activity of the nervous system both as a tonic and as a calming agent depending on the situation,
- in doing so, it regulates mood: feeling of well-being, reduction of anxiety, stage fright.
These 3 types of essential oils are therefore very different but have in common calming, digestive and slightly antibacterial-antimycotic properties.
When applied to the skin, they can induce a photo-sensitization reaction and some people are allergic to them.
Fresh orange juice is a good source of Vitamin C, it is the subject of a very active international trade, huge orange groves (in Brazil, Florida ..) provide fruits which are processed in the factory, the Raw fruit juice is sometimes carried by tanker across oceans.
We will always prefer the orange from an orchard not treated with pesticides.
Consuming fresh orange juice in the morning for breakfast is an interesting North American custom, but not everyone can stand the relative "acidity" of this juice.
ORANGE FRUIT AND ORANGE TREE EXTRACTS
Orange and orange extracts are digestive antispasmodics, soothing, they calm benign palpitations, cardiac erethism and facilitate the onset of sleep .
They can be used in cases of nervousness, insomnia, aerophagia, belching, digestive cramps due to emotion or anxiety, for example:
* Flowers in infusion: a tablespoon for a cup of very hot water, 1 to 3 times a day.
* The leaf infusion: 20 g of dried leaf or 3 to 5 fresh leaves per cup of very hot water, 15 minutes of infusion, 1 to 3 cups per day.
* Flower essential oil (rather for "nervous" disorders): 2 to 3 drops, 2 times a day in honey or on bread or in milk.
* The essential oil of orange, or small grain rather for digestive disorders and insomnia, 2 to 3 drops, 2 to 3 times a day in honey, on bread or in milk.
* You can incorporate the essential oils of orange and petit grain in dermatological or cosmetic preparations, but you must not then expose yourself to the sun (risk of photosensitization).
* orange essential oil is interesting in cooking or drinks, it brings a pleasant "exotic" note and can promote digestion.
There are specialties in pharmacies that contain citroflavonoids,to protect small blood vessels.
Finally, if you are used to eat all the orange (except the skin), that is to say the pulp plus the whitish and tasteless mesocarp, you will regulate your digestive transit thanks to the pectic matter it contains.
ORANGE EXTRACT AND SLIMMING DIET
We think that slimming supplements that contain bitter orange peel extracts are not recommended , they are often mixed with caffeine and the risk of cardiovascular disorders is not negligible: arrhythmias , palpitations, hypertension and even potentially myocardial infarction.
They can cause nervousness, insomnia and even increase food intake !!
THE FRUIT OF THE HESPERIDES GARDEN
The Chinese orange gives us the sweet orange full of vitamin .
Its leaves are used to make a soothing herbal tea
The bitter orange tree is the ancestor, the medicinal orange tree with its flowers, leaves, fruits and essential oil.
Both are plants that calm, help digest and facilitate the onset of sleep.
Some dietary supplements for weight loss contain bitter orange extracts rich in synephrine, their interest is controversial.
Copyright 2020 : Dr Jean-Michel Hurtel