BROAD-LEAVED SPURGE

Euphorbia platyphyllos

Spurge Family [Euphorbiaceae]

month8jun month8june month8jul month8july month8aug month8sep month8sept

status
statusZarchaeophyte
flower
flower8green
inner
inner8yellow
morph
morph8actino
petals
petalsZ0
type
typeZumbel
stem
stem8round
stem
stem8hollow
stem
stem8milkysap stem8milkylatex
toxicity
toxicityZmedium
contact
contactZmedium
rarity
rarityZuncommon

23rd July 2006, arable field, Medina Marina, Newport, IoW Photo: (CC by 2.0) Geoff Toone
An arable weed which grows in fields. It is much scarcer than most other Spurges apart from Upright Spurge which is very rare and the same order of rarity as Irish Spurge (which is a very rare [RRR]) and Sun Spurge and Portland Spurge (at an uncommon [R])


23rd July 2006, arable field, Medina Marina, Newport, IoW Photo: (CC by 2.0) Geoff Toone
In-between lanes in a field. It grows to 80cm.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
The plant is usually erect and lacks stipules.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
Here the stems are red, but they aren't always. Your Author assumes that, like all (most?) other Spurges, the stems are hollow and contain a toxic milky-white latex.


8th Sept 2008, Duxmore, Ryde, IoW. Photo: (CC by 2.0) Geoff Toone


8th Sept 2008, Duxmore, Ryde, IoW. Photo: (CC by 2.0) Geoff Toone
The bracts associated with flowers are in opposite pairs and rhombic in shape, attached directly to the stem without stalks.


9th Sept 2007, field, Brighstone Down, IoW. Photo: (CC by 2.0) Geoff Toone
There are no stipules (short protuberances from the stem just under branches or other junctions).


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
A circle of bracts occurs at the end of the stem where it splits into a few thinner stems (4 on the right stem with a 4-way split; only 3 on the left stem which splits into 3.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
It is a branched plant with round stems.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
The flowers are in 'umbels' of umbels, usually splitting in twos or threes, but it can be more.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
The large yellow-green bracts beneath the flowers in opposite pairs are broad at the flower end and taper to a point; some almost triangular in shape.


8th Sept 2008, Duxmore, Ryde, IoW. Photo: (CC by 2.0) Geoff Toone
The four glands on the cyathia (centre of photo, deep yellow) are rounded on their outer edge. There is only one stamen on each flower for Spurges, in the top flower it can be seen emerging from the centre of the yellow cyathia, along with the ovary (not yet ripe) with its nominal two to three styles atop.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
Four yellow rounded cyathia visible.


24th June 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
The fruit capsules have three compartments and 2 or 3 stigmas, sometimes branched like the one on the right; all with small yellow styles atop. The capsules are hairless and have hemispherical pimples on the surface. Inside are smooth seeds.


9th Sept 2007, field, Brighstone Down, IoW. Photo: (CC by 2.0) Geoff Toone
The leaves are often different in shape to the bracts. Also, the leaves on the main stem are alternate (rather than opposite as they are on Caper Spurge).


Midsummer's Day!, 2006, a field, Tennyson Down, Totland, IoW Photo: (CC by 2.0) Geoff Toone
The leaves can be broader than these leaves, or even narrower, which is strange given the common name. Sorry, your Author does not have a better photo of a 'broad' leaf, which are obovate to elliptic. They are alternate on the stem, never opposite. The stem is round and hollow, without hairs, but the leaves can have hairs. The leaves do not have leaf-stalks and are attached directly to the stem (sessile) and are cordate at the stem clasping it, but they lack auricles.


Many similarities to : Sun Spurge (Euphorbia helioscopia). see captions for differentiating from other similar spurges.

It is a glabrous or hairy archaeophyte and annual plant growing to 80cm high. The stem is hollow and contains a toxic milky latex, as do most (all?) other Spurges.

The diterpenoids obtained from Broad-leaved Spurge are four Jatrophanes similar to those isolated from Upright Spurge (Euphorbia stricta (Previously known as E. serrulata), which is of taxonomic importance enabling a botanical similarity between the two species to be established. It also contains Abietane diterpenoids (unless these are the same as the Jatrophanes???)

JATROPHANE DITERPENOIDS

Jatrophanes selectively bind to and inhibit the ATP-dependent efflux pump P-glycoproten (Pgp). As such, they may be valuable in treating multi-drug resistant cancers which are common encountered. Unforyunately, to make new Jatrophane type diterpenoids for testing, several routes to synthesize them in the laboratory are required, but only a few routes have been found.

In most Jatrophanes, the cyclo-Pentane ring is fused to a larger ring which in turm is fused to another large ring; three fused rings in all. But in these Jatrophanes, the second two rings are broken resulting in a single large 12-membered ring with a broken bridge. In the case of the first 3 shown here, the bridging moiety is still present, but broken.

Jatrophane diterpenoids with a macrocyclic ring occur exclusively in both the Spurge Family (Euphorbiaceae) and Mezereon Family (Thymelaeaceae) families. Some of these compounds are of profound interest due to their cytotoxicity and antitumour properties, as well as their anti-viral and their ability to reverse multi-drug resistance. Jatrophane diterpenoids are found in nature, such as plants like thse, in their partly oxidised forms, mainly as polyesters (those side-groups sticking out - not polyester the plastic).

Similar, but not identical, Jatrophane diterpenoids to those found in Broad-leaved Spurge are to be found in Upright Spurge (Euphorbia stricta) (old name Euphorbia serrulata).

There are two totally different compounds with the same common name: Pubescenol, one a Jatrophane Diterpenoid, the other a Withanolide. Only the Jatrophane Pubescenol is present in Broad-leaved Spurge.


The Withanolide version of Pubescenol is not present in any Spurge, but instead in Chinese Lantern (Physalis pubescens) [which should not be confused with another plant with the same common name: Chinese Lantern (Abutilon pictum) which belongs in a differing family (Malvaceae)]. As you can see, the two are totally different, which fact had your Author completely puzzled when he tried to look up the chemical structural formula for Pubescenol and ended up with a totally unexpected structural formula.



Altotibetin, as its name may imply, was first found in Euphorbia altotibetic which some Chinese scientists observe. They may mean Euphorbia altotibetica? In fact they found not one, but 4 new Jatrophanes in this Spurge which they named Altotibetin A, Altotibetin B, Altotibetin C, Altotibetin D; a fifth was named Altotibetin E by another group of researchers. It is not known which, if any, of these Altotibetins it is that is also found in Broad-leaved Spurge. One presumes the 'A' version.


Pl-3 is yet another jatrophane-type diterpenoid found in Broad-leaved Spurge. Both Pl-3 and Pl-4 have a benzene ring moiety as a side group attached to the cyclopentane ring. Altotibetin has the benzene ring side-group attached to the main 12-membered ring instead, whilst Pubescenol lacks it altogether.


Pl-4 is yet another jatrophane-type diterpenoid found in Broad-leaved Spurge. Pl-4 has two double-bonds in the 12-membered ring, all the others have but one. All four have at least 4 (most have 5) acetoxy side-groups, which is what is meant by the 'polyester' moniker.

CEREBROSIDES

Broad-leaved Spurge also contains four Cerebrosides, Cerebroside 1 to Cerebroside 4, the first 3 (Cerebroside 1 to 3) which are the 1-O-β-D-Glycosides of PhytoSphingosines. In Cerebroside 1-3 the PhytoShingosides comprise of the same long-chain base, a 2-AminoOctadec-8-ene-1,3,4-triol while that last of a 2-AminoOctadeca-4,8-Diene-1,3-Diol; but all are terminated by 2-Hydroxy Fatty Acids of various chain lengths (C16:0, C24:0, C26:1 and C28:1 which is linked to the amino group. Those with a number other than zero after the colon, :, are Singly UnSaturated Fatty Acids.

The C16:0 is Palmitic Acid (aka HexaDecanoic Acid), CH3(CH2)14)COOH.

The C18:0 is Stearic Acid (aka OctaDecanoic Acid), CH3(CH2)16)COOH and is found in tallow (candle-wax) and cocoa butter the ester of which is used to make soap, shampoos and shaving cream.

Whilst the following are singly un-saturated fatty acids:
The C16:1 is Palmitoleic Acid, CH3(CH2)5CH=CH(CH27)COOH which is found in Macadamia Nuts.

The C24:1 is Nervonic Acid (aka SelaCholeic Acid), CH3(CH2)7CH=CH(CH213)COOH, which is found in the seeds of Flax, sesame Seed, and Macadamia nuts.

The C26:1 is HexaCosenoic Acid. [Your Author has failed to find the long formula for this one]

These large compounds are all amines, containing a single Nitrogen atom (in the top chain)

Broad-leaved Spurge accumulates complex SphingoGlycoLipids such as these.

This has only recently been found in Broad-leaved Spurge but was previously known in Mediterranean Spurge (Euphorbia characias ssp. wulfenii); the other 3 constituents have been known about for some time and they have also been identified in the rare Purple Spurge (Euphorbia peplis)







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Distribution
 family8Spurge family8Euphorbiaceae

 BSBI maps
genus8Euphorbia
Euphorbia
(Spurges)

BROAD-LEAVED SPURGE

Euphorbia platyphyllos

Spurge Family [Euphorbiaceae]