Not to be semantically confused with : Pasque Flower (Pulsatilla vulgaris) [a plant with similar name belonging to the Buttercup Family (Ranunculaceae)]
Uniquely identifiable characteristics
Distinguishing Feature :
Despite the numerous rayed petals this plant does not belong to the Dandelion & Daisy Family (Asteraceae).
It is a climber, clambering by tendrils up to 10 metres in length, although not necessarily all in height. It has an un-pleasant odour said to be similar to turpentine. It bears rather small bright orange coloured fruits which although edible, are somewhat insipid.
There are about 500 different varieties of Passion Flower, many are cultivated garden plant. The fruit is edible in one variety,
Purple Passionflower (Passiflora edulis), and is grown in South America, South Florida, South Africa and the Caribbean as a commercial crop abroad which are called 'Passion Fruit', this variety producing a purple fruit. Passion Fruit is often added to other fruits in the making of concentrated cordials to enhance the aroma. In Israel a wine or 'Sicar' is made from Passion Fruits. Sweet Grandilla (Passiflora ligularis). Another much rarer non-native variety,
Giant Grandilla (Passiflora quadrangularis) is also grown commercially for its much larger Passion Fruit. Several other species are grown for their fruits, some banana-shaped as in the Banana Passionfruits produced by two species, (Passiflora tripartita var. mollissima) and (Passiflora tarminiana).
Most other species of Passionflower produce poisonous fruits and are poisonous themselves.
It is much more likely to be found growing in someones' garden as a garden flower than in the wild. The one variety which does grow wild, Passiflora caerulea, is rather tender and sensitive to heavy frosts, and is therefore only likely to be found growing wild in a major city in the UK which has a considerable 'heat-island' effect such that temperatures at night do not fall quite so low as in the rural areas. Such a place appears to be Greater London, which is where it is most often found wild.
Many species of Passion flower exude a nutrient-rich nectar which attracts ants that will then attack and kill other insect pests of the plant that happen to be feeding on the flowers. It thus encourages ants for its own defence.
Chrysin is a flavone which is harvested from Blue Passionflower for its supposed health properties, and is said to reduce anxiety and treat insomnia, hysteria and epilepsy. Chrysin is yellow and it will variously yield a yellow dye when mordanted with aluminium, an orange dye mordanted with chromium or a chocolate-brown dye mordanted with iron, the same as does Apigenin.
Pelargonidin is a bright orange coloured anthocyanidin, which are all necessarily anti-oxidants.
It is found as the glycoside or diglycoside (or both) in Red Geraniums and in the fruits of
Plum, Cranberry and in large amounts in Red Kidney Beans.
The diglycoside of Pelargonidin is found in Blue Passionflower. Much reference is made of the 3-diglycoside of Pelargonidin within Blue Passionflower, but no structural diagrams are ever presented and neither is it claimed to be present in any other plant. However, the 3-,5-diglycoside of Pelargonidins are extensively referenced within the literature, with structural diagrams too, and your Author therefore believes that it is the 3-,5-diglycoside that is present in Blue Passionflower rather than the oft quoted and probably non-existent '3-diglycoside' (although there is a 3-glycoside of Pelargonidin which is also found in the fruits of
Strawberry) and many other reddish plants.
It seems probable that Pelargonidin-3,5-diglycoside adopts a red colour within the acidic environment of the fruits of Blue Passionflower.
β-Carbolines are all based upon the Carboline skeleton, shown above, which is an indole moiety with an extra fused
pyridine ring. It is not said to be present in Blue Passionflower. β-Carboline has a similar structure to Tryptoline and Pinoline, which are all related to the Tryptamines which like β-Carboline are all indole alkaloids. Tryptamine plays a natural role in the human brain as a neurotransmitter and neuromodulator and Pinoline is produced in the pineal gland during the metabolism of Melatonin, so it is little wonder that chemical mimics like the β-carbolines can interfere with this system. And so it is: the β-carbolines are psychoactive substances.
Blue Passionflower contains small quantities (up to 0.01%) of several β-carboline harmala alkaloids which are Monoamine Oxidase Inhibitors (MAOI) and have anti-depressant properties.
Harman is the most common, but
Harmaline, Harmine and
Harmol have also been found within Blue Passion Flower (and several other Passionflowers).
Harmaline is a CNS stimulating alkaloid and many of these compounds, and some others, play a role in the mind altering properties of a drink called ayahuasca which is prepared from the Banisteriopsis caapi vine, which grows in South America in countries such as Peru.
Harmine is fluorescent green under UV illumination.
β-Carbolines are also produced within the poisonous
Syrian Rue (Peganum harmala) (from which the Harmala alkaloids are named) is another non-native plant native to Iran which has medicinal uses. Compared to Passionflower which has only 0.01% Harmala alkaloids and is not considered very psychoactive, Syrian Rue contains over 5% and is.
ODOROUS ESTERS WITHIN PASSION FRUITS
Esters such as EthylButyrate,
Ethyl Caproate (aka
Ethyl Hexanoate) (both of these smells similar to
n-Hexyl butyrate (apple like smell) and
n-Hexyl Caproate (aka
Hexyl Hexanoate) give the fruits their fruity smell. Many of these fruity-smelling compounds are used in the baking, confectionery, food and perfume industry. Many have deleterious effects in the concentrated pure liquid form, but are innocuous in the tiny amounts used commercially. Indeed, since many fruits contain these or similar esters, they too would be inedible if they were deleterious to health.
Nonacosane is also present in some species but this cannot be the terpene responsible for the un-pleasant turpentine-like odour in Blue Passionflower since nonacosane is odourless, but it may play a role in the attraction of ants, since Nonacosane has been reported to be a pheromone component of the moth Ogyryia leucostigma.
Other alkaloids found within Blue Passionflower include the Cyanogenic Glycoside
Gynocardin, which was originally found in the seeds of Gynocardia odorata, a non-native evergreen tree from the Far East belonging to the Achariaceae family which is unknown in the UK.
Gynocardin, as a
cyanogenic glycoside containing latent hydrocyanic acid (by means of the CN group), is poisonous when eaten, the poisonous cyanide only being released as the sugar(s) are metabolized. For modus operandi of cyanogenic glycosides, see Bracken.
CAROTENOID DEGRADATION PRODUCTS
β-Damascenone is a florally scented compound found in
Tomatos, and in the fruits of Raspberry,
Passionfruit. It is also found in drinks such as beer, wine and rum.
Theaspirone is a spirofuran compound found in the fruits of Yellow Passionflower but also in the non-natives
Black Tea and
Burley Tobacco. It too is a volatile aroma compound and an odiferous principle of tea.
Oxoedulan I and
Oxoedulan II are both found within Purple Passionfruits (rather than the yellow fruits of Blue Passionflower). The only difference between the two Oxoedulans are the stereoisometric positioning of one of the two the lone methyl groups, both are flavour/aroma compounds derived from the decomposition of carotenoids. They are also both found in the non-native plants
Virginia Tobacco and shrubs of the Osmanthus Genus (in the (Oleaceae) family).
AROMA COMPOUNDS containing SULFUR
Both of these sulfurous ring compounds are to be found in trace amounts (less than 20ppb) in yellow Passionfruits, such as Passiflora edulis f. flavicarpa, where even in those minuscule amounts contribute to the odour and flavour. The γ-Sultines (chiral cyclic (or bicyclic) sulfinates and are not 'sulfines' mis-spelled) were a new class of flavour compounds in the year 2000.