Changes

:Chromosome number: ''x''= 6, 7, 8, 9, 13, 15, most commonly 13;''P. acidus'': 2''n''= 26,''P. amarus'': 2''n''= 26, 52,''P. emblica'': 2''n''= 98, 104,''P. maderaspatensis'': 2''n''= 26, 52,''P. pulcher'': 2''n''= 78,''P. reticulatus'': 2''n''= 26,''P. simplex'': 2''n''= 26,''P. urinaria'': 2''n''= 52

*''Phyllanthus acidus'' (L.) Skeels, *''P. amarus'' Schum., *''P. emblica'' L., *''P. reticulatus'' Poiret.

*Phyllanthus, seaside laurel (En). *Phyllanthe, bois à enivrer, bois de gaulettes (Fr)

The medicinal applications of ''Phyllanthus'' have a long history. Several ''Phyllanthus'' species have been used in India for about 2000 years in the Ayurveda, Unani and Siddha systems of medicine, especially for the treatment of jaundice. Although the species may vary locally, ''Phyllanthus'' is used in virtually the whole of South-East Asia, the Pacific, East, West and Central Africa, the Caribbean and South America. Generally ''Phyllanthus'' has aphrodisiac, diuretic and purgative properties, and is used in the treatment of chest complaints, conjunctivitis, cough, diabetes, diarrhoea, oedema, fevers, hepatitis, nephritis, ophthalmic diseases, smallpox and venereal diseases. Some of the medicinal ''Phyllanthus'' species are also used for dye and tanning purposes (e.g. ''P. emblica'' , ''P. reticulatus'' ), as edible fruits ( ''P. acidus'' , ''P. emblica'' ), and as ornamentals ( ''P. pulcher'' ). The wood of ''Phyllanthus'' ( ''P. acidus'' , ''P. emblica'' , ''P. reticulatus'' ) can be used for utensils and other small objects, and as firewood.

In India, ''P. amarus'' , ''P. debilis'' and ''P. fraternus'' Webster are generally collected from natural stands, often on well-drained, cultivated ground in the rainy season. ''P. amarus'' is sometimes also cultivated in small plots and sold on local markets. Fruits of ''P. emblica'' are gathered from wild and garden trees and used for local consumption or sold on the market. In India, preserves made from these fruits are manufactured and marketed on a large scale.

The latex of many members of the ''Euphorbiaceae'' is known for its toxicity; it causes inflammations of the skin and mucous membranes, conjunctivitis and sometimes even blindness. The latex of ''Phyllanthus'' can also cause allergic reactions. Several ''Phyllanthus'' species are poisonous to livestock or fish and can be allelopathic to desirable forage plants. Various groups of medicinally interesting compounds are present in ''Phyllanthus'' , including triterpenoids, flavonoids, tannins, alkaloids and phenolic acids. Triterpenoids have been isolated from ''P. acidus'' (phyllanthol, β-amyrin), ''P. discoides'' Muell. Arg. (betulinic acid), ''P. emblica'' (lupeol, lupenone), ''P. reticulatus'' (friedelin, β-sitosterol, betulinic acid, glochidonol, friedelan-3-β-ol, 21α-hydroxyfriedelan-3-one, 21α-hydroxyfriedel-4(23)-en-3-one) and ''P. urinaria'' (β-amyrin, β-sitosterol, triacontanol). Flavonoids have been found in ''P. amarus'' (quercetin-3-O-glucoside, rutin), ''P. emblica'' (quercetin, kaempferol, kaempferol-3-O-glucoside (= astragalin)) and ''P. urinaria'' (quercetin, kaempferol, rutin). Tannins have been isolated from ''P. amarus'' (mainly geraniin, amariin and gallocatechin) and ''P. emblica'' (e.g. phyllembin, gallotannin as 1,2,3-trigalloylglucose and the ellagitannins terchebin, corilagin, chebulagic acid and chebulinic acid). Alkaloids, mainly of the quinolizidine type, have been reported for ''P. amarus'' (phyllantine, securinine, norsecurinine, isobubbialine, epibubbialine) and ''P. discoides'' (allosecurine, phyllantidine, phyllantine). The quinolizidine alkaloid phyllantine (= methoxy-securinine) must not be confused with phyllanthin and hypophyllanthin, which are lignans isolated from e.g. ''P. amarus'' and ''P. urinaria'' . Furthermore, a range of phenolic acids has been isolated from ''P. acidus'' , ''P. emblica'' , ''P. maderaspatensis'' , ''P. reticulatus'' and ''P. simplex'' .

''P. amarus'' , ''P. debilis'' and ''P. urinaria'' have all been found to inhibit DNA polymerase of the hepatitis B virus and other hepatitis-DNA-viruses, such as the woodchuck hepatitis virus (WHV). Lesser known species of the same subgenus ''Phyllanthus'' also showed this effect, but species from other subgenera generally show much weaker inhibitory activity. However, intraspecific differences make it difficult to compare the activity of the different species. In some other studies, ''P. urinaria'' extracts showed inhibitive effects on duck hepatitis B virus (DHBV) polymerase, whereas ''P. amarus'' and ''P. maderaspatensis'' extracts were found to lack antiviral activity against DHBV.

The triterpenoid triacontanol isolated from ''P. urinaria'' has hepatoprotective properties, e.g. against galactosamine-induced cytotoxicity in rat hepatocytes. This may, at least partly, confirm the hepatoprotective action shown by alcohol extracts of ''P. urinaria'' in rats. Furthermore, hydroalcoholic extracts of ''P. urinaria'' have shown analgesic effects against formalin-induced and capsaicin-induced pain in mice (antinociceptive activity), and methanol extracts have demonstrated hypoglycaemic activity in diabetic rats. ''P. urinaria'' plant extracts exhibited some antibiotic activity against ''Staphylococcus'' , ''Escherichia coli'' , ''Salmonella typhi'' , ''Vibrio cholerae'' and ''Shigella dysenteriae'' bacteria.

Finally, extracts of ''P. reticulatus'' , especially aqueous extracts of the leaves, have shown in vitro activity against ''Plasmodium falciparum'' .

*Monoecious or dioecious herbs, shrubs or trees of various habit; branching either unspecialized (the phyllotaxy spiral or distichous) or phyllanthoid, i.e. the spiralled leaves on the main axes reduced to cataphylls which subtend a deciduous branchlet with distichous leaves, the latter resembling a compound leaf; indumentum present or absent, simple or rarely dendritic. *Leaves alternate, simple, entire, shortly petiolate; stipules present, those of cataphylls larger than those of foliage leaves. *Inflorescence axillary, composed of a solitary flower or of a vestigial, bisexual or unisexual cyme, these cymes occasionally aggregated into thyrses. *Flowers unisexual, small, apetalous; calyx 4-6-lobed, the lobes imbricate in bud; disk nearly always present. Male flowers with 2-6(-15) stamens, filaments free or connate, anthers free or connate (and forming a "synandrium"), extrorse; pistillode absent. Female flowers usually without staminodes; ovary superior, sessile or stipitate, 3(-12)-locular with 2 ovules in each cell, styles 3 or rarely more, free or connate at base, bifid, multifid, or dilated into an entire or lacerate stigma. *Fruit usually a dehiscent capsule, less commonly baccate or drupaceous. *Seeds usually triquetrous, smooth or variously ornamented, testa usually thinly crustaceous; endosperm present. *Seedling with epigeal germination; cotyledons emergent, leafy, persistent; hypocotyl elongated, often first curved in a loop above the soil; all leaves alternate, sometimes the first few scale-like, in species showing phyllanthoid branching a few normal leaves are generally produced, followed by cataphylls.

In Java, all medicinal ''Phyllanthus'' species flower throughout the year, except for ''P. emblica'' , which flowers in August. In India, the fruits of ''P. emblica'' remain dormant throughout the summer and begin to develop as the monsoon starts.

''Phyllanthus'' belongs to the subfamily ''Phyllanthoideae'' and is related to ''Breynia'' , ''Glochidion'' , ''Phyllanthodendron'' and ''Sauropus'' which all show phyllanthoid branching. The genera ''Cicca'' and ''Emblica'' are incorporated in ''Phyllanthus'' , although occasionally still treated as being distinct. ''Phyllanthus'' has been subdivided into 10 subgenera which are sometimes further divided into a number of sections.

The species ''P. simplex'' and ''P. virgatus'' P. Forst. are sometimes regarded as a single species, ''P. virgatus'' sensu lato, but the mainland populations ( ''P. simplex'' ) appear separable from those in the Pacific ( ''P. virgatus'' sensu stricto) although there are records of intermediate specimens. Another taxonomic problem concerns ''P. niruri'' L. Asiatic specimens formerly assigned to this species actually belong to either ''P. amarus'' , ''P. debilis'' or ''P. fraternus'' Webster, whereas true ''P. niruri'' is restricted to the West Indies. Much of the research performed with " ''P. niruri'' " in Asia, mainly in India, thus needs botanical correction.

''P. amarus'' (often reported as ''P. niruri'' ) is a troublesome weed in pulses, soya bean, groundnut, cereals, sugar cane, cassava, taro, sesame, sunflower, and cotton. Less important weeds are ''P. debilis'' , ''P. maderaspatensis'' , ''P. simplex'' and ''P. urinaria'' , outside South-East Asia also ''P. fraternus'' . The species belonging to the subgenera ''Phyllanthus'' (e.g. ''P. amarus'' , ''P. debilis'' , ''P. emblica'' , ''P.urinaria'' ) and ''Isocladus'' (e.g. ''P. maderaspatensis'' ) show a marked preference for calcareous sites in humid tropical areas. In China, warm, well-drained sandy soils and fertilization with N and K are recommended for cultivated ''P. urinaria'' . ''P. urinaria'' is more drought-sensitive than ''P. amarus'' and ''P. debilis'' and is generally found in wetter sites. ''P. amarus'' grown in greenhouses at a temperature of 15°C showed much less inhibitory activity on the DNA polymerase of woodchuck hepatitis virus (WHV) than when grown at 25°C. ''P. emblica'' is a short-day plant, requiring photoperiods of 12-13.5 hours for flowering. It can be grown in both light and heavy soils, but it prefers well-drained, fertile loamy soils. Seeds of the herbaceous ''P. debilis'' , ''P. simplex'' and ''P. urinaria'' are dispersed by water and animals.

Callus can be induced from stem or phyllanthoid branch pieces of ''P. amarus'' and ''P. urinaria'' , but callus extracts showed less activity against viral DNA polymerase and reverse transcriptase than extracts from field-grown plants. Phyllemblin present in extracts of in vitro ''P. emblica'' tissue cultures showed antimicrobial activity against bacteria ( ''Escherichia coli'' , ''Staphylococcus aureus'' , ''Salmonella typhosa'' ) and a fungus ( ''Candida albicans'' ).

Most material used for medicinal purposes is collected from the wild. Though ''P. amarus'' is also cultivated in India, there is no information on any specific cultivation measures. Soil fertility and soil moisture experiments in the United States affected morphology and yield of ''P. debilis'' and ''P. urinaria'' , with plants being shorter, more branched and with a higher dry weight under favourable conditions. Differences in soil fertility and soil moisture generally did not affect these species' in vitro inhibitory activity on WHV viral DNA polymerase. In ''P. amarus'' , maximum dry weight is obtained in wet neutral soils, but differences in soil moisture, pH and Ca content did not affect the inhibitory activity of plant extracts. These findings imply that plant yields can be maximized through cultivation measures, without affecting the antiviral activity of plant material.

In India, ''P. simplex'' is infected by mildew ( ''Erysiphe cichoracearum'' ), which appears as small, circular, whitish powdery spots on leaves, petioles and stems.

Caterpillars of ''Parallelia absentimacula'' and ''P. joviana'' feed on ''Phyllanthus acidus'' in Indonesia. The main pest of ''P. emblica'' in India is the bark-eating caterpillar ''Indarbela'' sp., which tunnels into the trunk and branches. ''P. urinaria'' weed in Indian rice fields is infested with the rice root-knot nematode ( ''Meloidogyne graminicola'' ).

There is rich genetic diversity in cultivated and wild relatives of ''P. emblica'' in India, but genetic erosion is severe because of deforestation and the use of only a few popular cultivars. Germplasm survey, collection and evaluation work has been done and accessions are maintained at Narendra Dava University of Agriculture and Technology in Faizabad (India). Other accessions are reported to be kept in Havana (Cuba), Uttar Pradesh (India), Udaipur (India), Bangkok (Thailand) and Miami (United States). No breeding has been done on other ''Phyllanthus'' , except for ''P. emblica'' .