Solanum torvum

Solanum torvum has a native range from Mexico to Peru and Venezuela, and in the West Indies and Bermuda . This plant is highly invasive and has become a noxious weed in many countries. Solanum torvum has both edible and medicinal properties.

Fig 1. From Rendle's 1938 The classification of flowering plants.

Solanum torvum	Pea eggplant/Thai eggplant
SOLANACEAE
Identification Shrub <3m. Alternate, lobed to deeply lobed leaves 7-25cm,  ovate to ellipticpetioles 1-5cm, entire leaf and young shoots covered in stellate hairs.  Stems with recurved thorns <10mm. Inflorescence racemose panicles. Stellate pubescent peduncle.	Cultivation  Weed status in Australia. Subtropical-tropical, enjoys moist environments. Please don’t cultivate this weed, wild harvest is preferable. In unrelated plant studies, plants grown in wild as opposed to cultivated environments exhibited higher concentrations of active ingredients.
Flowers  Year round	Fruits   May...
Etymology	Warning   Some Solanum species are poisonous, dangerous or hallucinogenic.
Edibility Edible fruit	Medicinal Anti-bacterial Anti-inflammatory Analgesic Anti-viral Anti-ulcerogenic

Figure 2. Solanum torvum habit; growing as a midstorey on a wetland edge.

Figure 3. Solanum torvum fruit, “Pea eggplants”.

Solanum torvum has been used as a wild food for centuries, and although it is known in many parts as “Thai eggplant”, it was only introduced into Thailand relatively recently. Pea eggplant has been introduced and naturalized throughout tropical Africa, Asia, Australia, and the Pacific Islands. The fruit are picked when immature and pale green, and cooked before eating. They can be very bitter, depending on the maturity of the fruit, and are commonly used in curries.

I stir-fried some berries that I picked locally, but they were too bitter for me to eat. My friend from Thailand said that steaming them is better, and makes them less bitter, so I will try that.

Solanum torvum has been used a traditional medicinal plant by many peoples, and several of its attributes are the subject of current pytopharmalogical research. In Cameroon (Africa), S. torvum has been used to treat abscesses, jigger wounds, skin infections (ringworm, athletes foot), and dermatophilosis in animals. Additionally it has been used to treat stomach complaints, such as ulcers.  Under laboratory conditions, Solanum torvum has been shown to inhibit bacterial growth, and exhibits anti-ulcerogenic properties.

S. torvum has also been used in “folk medicine” to treat fever, and for analgesic and anti-inflammatory purposes. In India it has been used to treat respiratory tract disorders, gastro-intestinal tract  disorders and STD’s.

I bought these once, from a market stall, not knowing what they were. They tasted quite bitter, and I did not eat many, as I knew my body had never had them before, and it is always best to be cautious when trying something for the first time, especially plants with toxic species in the family. I was quite surprised to find out that they were the same fruit that grow on a common weed in my local area.

I have never used this plant medicinally, but am interested in experimenting with it now, as it has some great anti-fungal and anti-bacterial properties. I don’t plan on contracting ringworm just to see if it is effective, but if I have the opportunity to test S. torvum I will add an edit post.

Fig 4. S. Torvum flowers, showing 5 petals, with the key identifying solanum feature, 5 prominent stamen. 

References Chah, K., Muko, K. & Oboegbulem. 2000. Antimicrobial activity of methanolic extract of Solanum torvum fruit. Fitoterapia, 71:187-189 Nguelefack ,T., Feumebo , C., Ateufack , G., Watcho , P., Tatsimo , S., Atsamo , A. & Tane , P. 2008. Anti-ulcerogenic properties of the aqueous and methanol extracts from the leaves of Solanum torvum Swartz (Solanaceae) in rats. Journal of Ethnopharmacology, 119; 135-140   Mollick, Hossan, Paul, Rahman, Jahan & Rahmatullah. 2010.  A Comparative Analysis of Medicinal Plants Used by Folk Medicinal Healers in Three Districts of Bangladesh and Inquiry as to Mode of Selection of Medicinal Plants. Ethnobotany research & applications 8:195-218

Pipturus argenteus

This Australian native plant is useful both as a bush food plant and as a medicinal plant.

Pipturus argenteus	Native Mulberry
URTICACEAE
Identification Small tree or shrub <8m. Petioles; 0.5-9cm. Blades; ovate to narrow ovate. Apex; acuminate. Base; cuneate to obtuse. Margin; serrate. Leaf; 3.5-18cm x 1.8-8cm. Lower leaf surface; hoary white pubescent. Inflorescence; axillary, 3-7 clusters of flowers along a spike. Fruits; white/transparent  ~1cm, pitted irregularly.	Cultivation  Occurs naturally in rainforest margins, native to south-eastern QLD. Easily cultivated in backyards, prefers subtropical area. I have this growing ~2km from the coast, in sandy soil.
Flowers  summer to winter	Fruits   May-?
Etymology   “The generic name Pipturus is derived from the Greek pipto, to fall, and oura, tail, in reference to the caducous stigma.” From nativeplants.hawaii.edu.	Warning   None

  Figure 1. Leaves, note pubescence on underside of left leaf.

Figure 2. Fruit

Figure 3. Bark is olive green/brown,  with raised, textured striations that are warm brown.

Figure 4. Leaves are alternate.

Pipturus argenteus is a great plant, and very easy to grow. I never watered it, and it thrived. I have two growing, and one has a shrub habit, while the other (younger) has a tree habit, and is ~4.5 metres high, at ~3 years old. I have seen this plant self seed very easily in semi-natural rainforest, but it has not done so on my property yet.

A member of the Nettle family, this plant has NO sting. The fruit are quite nice, not particularly flavoursome, but gently sweet with a delicate flavour, and very soft, in fact it is difficult to pick them without squishing them, so they may never make it as a commercial crop despite being more-ish. They are eaten raw, but I suppose that they could be cooked.

Whilst I am not aware of any medicinal usage of this plant in Australia (that does not mean that there was none, there probably was, and if you know of any, please let me know), research conducted in Papua New Guinea states that it was used (on Buka Island) for several ailments. For coughs and stomach aches, the leaves are crushed with a little water, the solution is then squeezed out and drunk twice daily. For centipede bites, the scraped roots are chewed with betel nut and lime, the mixture then being rubbed into the bites, or leaves are crushed and applied directly to the bite. To help fresh wounds or tooth-ache, the sap is applied directly. Additionally, in Simbu Province, the sap feom the scraped inside bark is heated with the leaf of Rubus ledermanii and eaten daily to soothe a bad cough.

Edit; on the 17 August (2 days ago) I pruned my Pipturis, and found the green bark stripped off in long strips, I plaited some, and it holds together really well. Two days later, it is dry but still strong. I am reasonably strong and I couldn't break it by pulling. I think if three plaits were plaited together, or if it was made 2-ply before plaiting it could be used for many purposes. Plus, it is winter - the dry season here, so for bark to strip in winter is rare-ish.

It is almost 90cm long.

These photos were taken 2 days after making the cordage.

It is about 2mm thick.

References

Holdsworth, D. 1980. Traditional medicinal plants of the North Solomons Province Papua New Guinea. Quart. J. Crude Drug Res, 18;33-34

Holdsworth, D, & Sakulas, H. 1992. High altitude medicinal plants of Papua New Guinea Part II. Mount Wilhelm, Simbu province. Int. J. Pharmacognosy, 30; 1-4

Stanley, t, & Ross, E. 1995. Flora of south-eastern Queensland. Department of Primary Industries