Herbs from Distant Lands: Pilea melastomoides

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PLANT PROFILE

Pilea trinervia is a tropical, perennial semi-succulent subshrub from Urticaceae family. It grows naturally in mountainous regions of India, Sri Lanka, Indo-China, Taiwan, the Philippines and Indonesia. It's leaves are eaten as a vegetable, but except for Indonesia it is not commonly known as such and if so, than usually it is just gathered from it's wild state by villagers. In Indonesia, especially in Java, Sumatra and Bali, it is so much appreciated that it is also cultivated in vegetable gardens, on small scale farms, and often sold on local vegetable markets.
Pilea trinervia has a high reputation for it's unique aroma, good nutritious value and health benefits. That is why, although it is not very popular as other vegetables in the region, in last years it get some attention from scientific world. And few studies has been made in Indonesia to evaluate best techniques for it's commercial, big scale cultivation, and to test it's potential as a medicinal plant. Pilea trinervia is also occasionally planted as ornamental or hedge plant.
It's most popular common name used in Indonesia and Malaysia is Pohpohan, but Popongan and Seureuh Leuweung are also used in Java. It's other vernacular names include : Thuy Ma La Mua (Vietnam), Narali (Malayalam), Dongorbhori (Telugu), Chang Xu Leng Shui Hua (Chinese), Melastome Clearweed (English), Schwarzschlundige Kanonierblume (German).
Pilea trinervia is still often known as Pilea melastomoides, but it's other synonyms like Urtica melastomoides, Urtica trinervia are nowadays out of use.

CULTIVATION AND HARVESTING

Pilea trinervia is perennial subshrub with succulent young stems and semi-succulent leaves. It is usually less than 1m height but can reach even 2m, and it's leaves are 5-15cm long. It naturally grows in tropical, mountainous regions at elevation 700-2200m, in wet shady places in forests, near streams or lakes. It like wet but well drained rich compost soils, but can even grow on rocks with very little organic matter and withstand even very severe, long term droughts.
P. trinervia can be easily propagated by cuttings or layerings or from seeds. But the species is dioecious, which means that you have to have both male and female plants in order for pollination take place.
It was observed that Pohpohan plants are more susceptible to diseases if it grows in dry areas, and less in humid areas. Also that plants that grows in shade are even five times larger than those under full sunshine, and of course it produce more juicy and crispy vegetable parts.
Because of it's preference for shade, it is probably much more suitable for indoor pot cultivation than most of perennial, tropical, sun loving vegetables.
Pohpohan leaves can be harvested of it's own, but whole young stems are usually harvested. As it is more convenient, retain it's freshness better, plus tops of the stems are tender and juicy and can be consumed just like the leaves. It can be harvested all year round.

CULINARY USES

Pilea trinervia is quite popular wild vegetable in Java, Sumatra and Bali, where it is called Pohpohan. The leaves or whole young tender stems tops are mostly eaten raw as a salad, especially as a part of Lalapan dish (which is meat or fish, vegetables and sambal - sauce or paste made from chili that can have added ginger, shallots or shrimps for example), or rolled with chili paste inside. It is also steamed (to be a side dish for rice meal or other), boiled in soups and stews, or fried in tempura (for example with shrimp filling).
P. trinervia leaves have quite strong aroma for which it is highly appreciated, as most of people find this smell as nice, but some people call it too intense. Probably that is why I found one report stating that in India this plant is used more as a seasoning than a vegetable. But other source states that it is one of the wild edible plants that are important constituent of traditional diets in the Meghalaya.
I myself really like Pohpohan's distinguish refreshing aroma, but the leaves are for me too astringent, tart to be good as a leafy vegetable to be eaten fresh in quantities. It might be though that my plants had too much sun, and maybe it would have milder taste, if it would grow in shade and in softer compost instead of clayish one.
Since I much like good astringent teas like black Camellia sinensis or Persimon leaf tea, I get an idea to make a tea from Pohpohan leaves (although I didn't found anywhere any, even vague information about P. trinervia infusions or decoctions used as a beverage or even just as a cure). And the result is that I have another herbal tea on the list of my favorite beverages. The tea made from fresh chopped Pohpohan leaves has mild taste, with moderate astringency and quite strong, wonderful aroma unique to this herb. When it is dried and storaged carefully, the infusion made from crushed dried Pohpohan leaves taste just the same as the one from fresh leaves, without any loss of intensity of it's very pleasant aroma.

MEDICINAL USES

As a medicinal plant Pilea trinervia belongs to those shady herbs about which little is known, only few traditional claims of unknown genesis and scarce modern science data. But growing interest in medicinal properties of this well appreciated vegetable, might make this plant one day a widely used herbal cure, as it's high potential is already clear to see.
Just a few ethnobotanical reports contain scarce information that P. trinervia leaves are consumed as a treatment for cancer and stomachache in Bali, and cough, diabetes, stomach pain and post pregnancy in West Java. It is also said that Pohpohan leaf effectively increase body stamina. And there is one report from India, that - '' The leaves of the plant are used to cure allergies at the time of child birth. ''

Laboratory tests proved that Pohpohan is effective in lowering blood sugar level. Also it's strong antioxidant properties and antimicrobial actions was scientifically proved. Tests results shown that Pilea trinervia extracts are effective against Gram positive bacteria, but not effective for Gram negative bacteria. Tests on essential oil extracted from aerial parts of Pilea trinervia proved it to be antibacterial, antifungal and anti-candida (The Minimum Inhibitory Concentration values of Pohpohan essential oil are : against Staphylococcus aureus 2.52 µg/mL, Bacillus subtilis 5.04 µg/mL, Escherichia coli 322.5 µg/mL, Candida albicans 20.16 µg/mL, Aspergillus niger 1.26 µg/mL, and Microsporum gypseum 5.04 µg/mL).
From my own experience, I would add that it also an astringent and diuretic herb, certainly good for respiratory tract and stomach infections.

As the laboratory tests results has shown that Pilea trinervia is effective against Microsporum gypseum, fungus that can be the cause of ringworms, and Staphylococcus aureus, bacteria that is common cause of many minor skin infections such as pimples, impetigo, boils, cellulitis, folliculitis, carbuncles, scalded skin syndrome and abscesses. I think that use of poultice of smashed fresh Pohpohan leaves for those kinds of skin diseases, might be very helpful.
In Indonesia Pohpohan leaves are used for generations to heal burns. Test has shown that gel with Pohpohan leaf extract has burns healing activity.

Pilea trinervia leaves contains : flavonoids (quercetin, kaempferol, luteoin, apigenin, anthocyanins), alkaloids, steroids, polyphenols, tannins, monoterpenoids and sesquiterpenoids (including sulfur containing sesquiterpene - mintsulfide), chlorogenic acid, caffeic acid, ferulic acid, phenol and quinone compounds.
It have high content of proteins and available carbohydrates, also contains good amounts of calcium, potasium, magnesium, copper, beta-carotene, vitamin C, B1 and alpha-tocopherol (type of vitamin E).
Pilea trinervia aerial parts essential oil contains mainly : 2(10)pinene (14.85%), 1R-alpha-pinene (12.95%), Sabinene (12.66%), o-menth-8-ene (8.33%), germacrene-D (5.00%), beta-phellandrene (4.86%), 2-beta-pinene (3.91%), cis-ocimene (3.54%), cyclosativene (3.40%), zerumbone (2.95%), beta-elemene (2.81), 1,3,6-octarienene,3,7 dimethyl (2.78%), full list here.

Although there are no reports about any side effects of Pilea trinervia, either from Indonesia where a lots of people consume it regularly as a vegetable for generations, or from elsewhere. And laboratory tests results indicate that it is non toxic and safe for developed as pharmaceutical and nutraceutical products. The scientific data about this herb and it's folk use reports are still quite limited, and there is a risk that there might be some contraindications for it's uses. Therefore I would advice moderation in Pohpohan consumption for those which health condition is poor and can not be compromise.

PILEA BENGUETENSIS C.B.Rob.

Pilea benguetensis is a species endemic to the Philippines, that can be found only on damp shaded cliffs, ravines, etc., at high elevations (1300-2000m) in the mountains of Luzon. And these are the only information about this rare species, that can be found in literature and internet.
I have found it growing only in one area, on rocky, seasonally dry, river bed on outskirts of Baguio, Benguet. It get my attention due to resemblance to both Elatostema and Pilea species, as many species of those genus and even in whole family of Urticaceae it both belongs to, are edible and medicinal plants. And when I saw that it is actually very closely related to Pilea plataniflora (used in Traditional Chinese Medicine) and to Pilea trinervia, I decided to test it's potential edibility. With my own high cautiousness, safety protocol : first smell it, if smells good tear the leaf and lick the edge, if it tastes good and I feel good then after some time I take tiny bite to chew and spit out, if it tastes good and feel good then next day I can chew and swallow small bite, and if that caused no harm or unpleasantness then following day I can try bigger bit, and so on.
So now I can say that for healthy individuals like myself Pilea benguetensis can be probably as good as a vegetable/potherb as Pilea trinervia. I eat regularly few fresh leaves of P. benguetensis and I like it even more than leaves of P. trinervia. As it is less astringent and more aromatic than trinervia. I would say that it's aroma is more pungent, very herbal, hard to describe but with somewhat rosemary character. It is definitely worth species to be tested for it's possible medicinal value, that might be just like it's aroma even stronger than that of Pilea trinervia.