Changes

:Chromosome number: ''x''= 9;''P. acinosa'':''n''= 9, 2''n''= 36, 72,''P. americana'':''n''= 9, 2''n''= 36,''P. dodecandra'': 2''n''= 36,''P. octandra'': 2''n''= 36

*''Phytolacca acinosa'' Roxb., *''P. americana'' L.

The young shoots and leaves of several ''Phytolacca'' species, when cooked, are used as a vegetable. After their toxic constituents have been removed, the red fruits of ''P. americana'' can be used to colour wine and foods. Some species, particularly ''P. americana'' , are common ornamentals in temperate climates. They are sometimes weeds.

Anti-inflammatory activity is attributed to the triterpenoid saponins, such as phytolaccoside and esculentoside, which are common e.g. in the roots. The inhibition of antibody production may partially explain the anti-inflammatory effect. Fungistatic properties have also been attributed to the saponins (e.g. yiamoloside from ''P. octandra'' ). The bark and the roots of several species (e.g. ''P. dodecandra'' ) are poisonous for people and animals. The toxicity may manifest in hallucinations. Lethal poisoning of horses caused by ''Phytolacca'' roots has been reported. Patients using Chinese drugs containing ''Phytolacca'' have also been poisoned. Aerial parts of ''P. americana'' have been found to have antigalactagogic effects in cattle. The roots of ''P. acinosa'' and ''P. americana'' have hypotensive properties; they contain the hypotensive agents histamine and gamma-aminobutyric acid. When ingested, leaves of ''P. americana'' typically produce self-limited but severe gastro-enteritis, characterized by intense vomiting and frothy diarrhoea.

Tests with mice suggest that ''P. acinosa'' polysaccharides augment the immunological functions in vivo and inhibit tumour growth; the antitumour effect may be mainly related to the augmenting effect on macrophages in the mice. Leaf and seed extracts of several species have shown antiviral activity in tests, e.g. against golden mosaic virus and tobacco mosaic virus in beans and tobacco, and against sugar cane mosaic virus and cucumber green mottle mosaic virus, and also against viruses in animal cells. The complete amino acid sequence of antiviral protein from ''P. americana'' seeds has been determined. The proteins are ribosome-inactivating. The lectins from the roots of ''P. octandra'' are mitogenic for unseparated human peripheral blood lymphocytes and stimulate plasma cell formation. Lectins from the roots of ''P. americana'' are called pokeweed mitogen (PWM). They are haemagglutinating (tested with human blood group A erythrocytes) and mitogenic (determined by³H-thymidine incorporation in lymphocyte cultures). Pokeweed mitogen plays an important role in fundamental leukocyte research.

In Japan, roots of ''Cynanchum caudatum'' Maxim. are used as a substitute for ''Phytolacca'' roots; they are also diuretic. ''Hibiscus sabdariffa'' L., ''Tamarindus indica'' L. and ''Tacca leontopetaloides'' (L.) O. Kuntze show toxic activity against snails transferring the parasitic trematode ''Schistosoma mansoni'' (causing bilharzia), which is comparable to ''Phytolacca dodecandra'' .

*Erect or scandent perennial herbs, sometimes shrubs and rarely trees, usually glabrous except for the often papillate or short-haired main axis of the inflorescence; stems up to 3 m long, but up to 10 m when scandent, often angular; roots often long and fleshy or tuberous. *Leaves alternate, simple and entire, usually ovate-oblong to oblong-lanceolate, herbaceous, acute at both ends, petiolate; stipules absent. *Inflorescence terminal or pseudolateral, racemose, often long, sometimes spiciform. *Flowers usually bisexual, but sometimes functionally male or female, actinomorphic, pedicel often short; perianth 5-partite, herbaceous, greenish, whitish or pinkish during anthesis and dark red under the ripe fruit, tepals free, equal or slightly unequal, ovate or obovate to lanceolate, persistent, spreading during anthesis, later often reflexed; stamens (6-)7-22(-33), in 1 or 2 series, inserted on the outer margin of the disk, sometimes also partly on the underside of the disk, filaments usually free, filiform-subulate, anthers dorsifixed, bilobed at both ends; carpels (3-)5-10(-16), whorled, laterally connate into a superior depressed-globose ovary, or almost free ( ''P. acinosa'' and ''P. dodecandra'' ), ovules solitary and basal in each carpel, styles terminal on the inner angle of the carpels, subulate, short, erect or recurved. *Fruit a depressed-globose berry, longitudinally 5-10-furrowed, or apocarp, juicy, orange or dark red to black, usually 5-10-seeded. *Seeds strongly laterally compressed, oval to lenticular, inaequilateral at base, shining black; embryo large, peripheric, enclosing the endosperm.

''Phytolacca'' belongs to the subfamily ''Phytolaccoideae'' , together with the genera ''Anisomeria'' and ''Ercilla'' , which are both restricted to South America.

Mass multiplication is done by non-woody stem cuttings. It is advantageous to use a 50-75 mg/kg α-naphthalene acetic acid solution as root-promoting substance, and a slightly acid soil medium. After 6-8 weeks rooted cuttings can be planted in the field, usually at 1-3 m × 2-3 m. Propagation by seed is only appropriate for selection purposes. Soaking seed of ''P. americana'' in e.g. concentrated H₂SO₄prior to sowing improves germination rate. Seed of ''P. dodecandra'' takes about 14 days to germinate.

Betacyanins have been produced in cell cultures of ''P. americana'' initiated from stem explants. The cells were maintained in Schenk-Hildebrandt medium. The suspension was subcultured every week in darkness at 25°C, and calluses were subcultured every 3 weeks. Whereas in fruits prebetanin (betanin 6'-O-sulphate) and its isoform predominate, in the cell culture feruloylated derivatives occur as the major components. Callus cultures of ''P. americana'' can be stored at 4°C for at least 3 months, but betalain production of cultures that have been stored is inferior. A dual culture consisting of callus of ''P. americana'' and the fungus ''Botrytis fabae'' showed marked fungicidal activity to ''Cladosporium herbarum'' . The main active constituent of this extract was identified as phytolaccoside B.

''P. dodecandra'' plantings may be attacked by leaf and stem borers ( ''Gitona'' spp.), so far the only serious insect pests. Precautions have to be taken against soilborne insect larvae.

''Phytolacca'' occurs in South-East Asia only in cultivation or as an escape. The species highlighted here have a wide distribution and are rather commonly cultivated and naturalized outside South-East Asia. With the exception of ''P. dodecandra'' and some ornamentals (particularly ''P. americana'' ) there has been no serious selection and breeding.

*Razali Yusuf