David W. Unander

Usage and bioassays in Phyllanthus (Euphorbiaceae). IV. Clustering of antiviral uses and other effects

A number of species of the genus Phyllanthus (Euphorbiaceae) have been tested for their efficacy as antivirals, partly on the basis of references to traditional usage for the treatment of diseases possibly having a viral origin. There are also many references to indigenous uses and to laboratory assays for other biological activities in this large genus (550+ species). These citations have been arranged by subgenus, section, subsection and species and have been published in three previous papers. This paper summarizes selected clustering of usage and effect by subgeneric taxa. Consideration of the data from ethnobotany, in vitro assays and clinical trials supported the presence of some type of biological activity(s) particularly within the subgenus Phyllanthus. Although the herbaceous species of subgenus Phyllanthus have been extensively used to treat jaundice, and have generally inhibited hepadnavirus DNAp, effects on chronic infection with hepatitis B virus (HBV) or related viruses have generally been negative. Alternative explanations for the wide usage have been little explored. Other medical categories suggested possible leads for research, or possibly, herbal or galenic remedies with bona fide effects. In most cases, the data remain suggestive but not conclusive.

Uses and bioassays in Phyllanthus (Euphorbiaceae): a compilation: II. The subgenus Phyllanthus

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four parts, including (Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part II) covers the subgenus Phyllanthus.

Buckwheat. Fagopyrum esculentum Moench. Promoting the conservation and use of underutilized and neglected crops, Vol. 19

This book is a collaborative effort on multiple levels: between a scientist and an avid gardener as authors, and between a government ministry and a commercial firm as publishers. As such it is a book with identity issues, reflected throughout in the blending of styles, organization of information, and even the design of the text. The subject matter is fascinating and the authors are to be commended for writing a book for those who live and garden in extremely cold climates in North America. Sadly, not everything in this graft chimaera works. The introductory 15 pages or so describe methods for garden design and horticultural techniques suited to a climate where trapping and conserving heat, as well as making optimal use of the short growing season, is crucial to success. Cloches, cold frames, hot beds, and water jackets are all clearly explained and nicely illustrated. So far, so good. The main body of the book, comprising 145 pages, catalogs herbs that can be grown successfully under hard-winter conditions; these are keyed to a plant hardiness zone map that emphasizes the continental North America. The main entries are ordered by common name, with scientific name, plant family, and alternative common names provided. The total number of species covered is elusive; a number of taxa are mentioned in passing under some main entries, for example 3 cultivars and 3 additional species of Salvia are mentioned in the account of garden sage. Because there is no index it is impossible to access information about these herb taxa unless you remember what main entry they are described under. The lack of an index to all names used in the text is a serious shortcoming for a book organized in this way. However, once one gets oriented in the text, there is a great deal here to delight. The species accounts are organized in a logical sequence, filled with interesting information organized as bulleted points rather than prose. Selected bits of (usually historical) information have been set off in tinted boxes inserted in the text. The illustrations are set in the text, with lines of text often varying in length so they abut the artworks. These design features I found visually distracting, even irksome. The use of botanical art reproduced from 18th and 19th century works is unusual. The sources, however, are not identified, which precludes access to the information originally published with these historical artworks. A few species have been illustrated with original artwork that imitates the older style; these have been credited to the artists that created them. All in all Culinary Herbs for Short-Season Gardeners is a mixed bag. The authors have created an authoritative text, which fills a niche not addressed in the herb gardening literature. However, the amateurish design and layout do not serve the text well. For those avid herb growers and fanciers living in hard winter areas, the book is worth having. But it will require taking the time to become thoroughly familiar with it in order to use it effectively. This is not a book one can pick up to quickly answer a particular question, but rather one to sit and browse through by the fire on a long dark winter’s night.

Records of usage or assays in Phyllanthus (Euphorbiaceae) I. Subgenera Isocladus, Kirganelia, Cicca and Emblica

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published as three separate papers, followed by a paper discussing the apparent clustering of some uses or effects within taxa. This paper, the first of the series, covers the subgenera Isocladus, Kirganelia, Cicca and Emblica.

In vitro activity of Phyllanthus (Euphorbiaceae) species against the DNA polymerase of hepatitis viruses: effects of growing environment and inter- and intra-specific differences.

Extracts of Phyllanthus amarus (Euphorbiaceae) are known to reduce or eliminate detectable hepatitis B virus surface antigen in humans or surface antigen of woodchuck hepatitis virus in woodchucks. The objectives of the experiments in this paper were to evaluate the in vitro inhibición of viral DNA polymerase (DNAp) among (1) different species of Phyllanthus; (2) within the most promising species; and (3) to evaluate differences in activity that might be correlated with environmental effects. The ultimate goal of our studies is to develop a system for producing high quality plants for large scale extraction.Inhibitory activity varied significantly among species. InP. urinaria there were also significant differences among intraspecific accessions. Accessions ofP. amarus from various locations did not differ significantly. Experiments with one seedlot showed highly significant plant-to-plant differences in anti-viral activity, but clear-cut heritable differences were not established among progeny of the plants at extremes in the distribution. Differences in general soil fertility, soil moisture, pH or Ca generally did not significantly affect inhibición of viral DNAp but temperature differences did. Except for temperature, the detectable environmental effects were generally less than the size of the genetic differences among species.P. amarus was successfully grown as a row crop with inputs of fertilizer and irrigation and showed no loss of activity when compared to samples from the wild. Thus, once an accession of Phyllanthus with potent inhibición of viral DNAp is identified, it can be grown under cultivated conditions for extraction without a loss of activity.RésuméExtractosde Phyllanthus amarus (Euforbiaceae), reducieron o eliminaron los antigenos superficiales del virus hepatitis B en humanos o los antigenos superficiales de virus de la hepatitis de marmota en marmotas. Los objetivos de los experimentos descriptos en esta comunicaciôn son: evaluar por una medida de la actividad antiviral, la inhibición in vitro de la polimerasa viral DNA dependiente (DNAp), (1) la existencia de diferencias entre especies dePhyllanthus, (2) dentro de las especies mäs potentes, o (3) debidas a efectos ambientales. El objetivo ultimo de estos estudios era él de desarrollar un sistema para producir plantas de alta calidad para la extractión en gran escala.Dicha inhibitión es variable entre las especies probadas del género y, en un ensayo, entre varias lineas de P. urinaria. Lineas de P. amarus derivadas de semillas de varias localidades no mostraron diferencias en la inhibitión del DNAp viral. Un ensayo usando semillas de una localidad exclusivamente, mostró diferencias al nivel de P = 0.01 en la actividad antiviral entre plantas individuates pero estas diferencias no fueron muy heredables en los proles de la plantas más extremas de la distributión. Ensayos para probar diferentes condiciones en el suelo, como por ejemplo fertilidad general, humedad del suelo, pH o nivel de Ca, por lo general no mostraron un efecto significativo sobre la inhibitión del DNAp viral, sino la temperatura ambiental, sí. Cuando existieron efectos ambientales significativos, fueron menores que los efectos genéticos vistos en los otros experimentos, con la excepción del efecto de temperatura. Plantas de P. amarus de buena calidadfueron obtenidas sembradas en hueras y usando abono y riego por goteo. Estas plantas cultivadas no perdieron su actividad contra el DNAp viral al compararlas con extrados de plantas silvestres. Por lo tanto, una vez que se identifica una linea de Phyllanthus caracterizada por inhibición potente, se puede sembrar bajo condiciones del cultivo sin perder la actividad.

Callus induction in Phyllanthus species and inhibition of viral DNA polymerase and reverse transcriptase by callus extracts.

SummaryStudies on callus induction and growth in Phyllanthus amarus Schum. & Thonn. (Euphorbiaceae) and some related species are described, as well as the inhibition of enzymes of hepatitis B and related viruses by callus extracts. Callus was induced from stem or branch pieces of P. amarus placed on several media combinations. Optimum induction and growth of friable, undifferentiated calli occurred on Murashige and Skoog medium supplemented with either 0.5 mg or 1 mg of BA/liter and 1 mg/liter of either 2,4-D or IBA, but not IAA. Callus induction using the same media was also attempted with other Phyllanthus spp. The best success was with P. abnormis. Aqueous extracts from fieldgrown plants were more active in vitro against viral DNA polymerase and reverse transcriptase than extracts of calli.

Cultivation of Phyllanthus amarus and evaluation of variables potentially affecting yield and the inhibition of viral DNA polymerase.

Phyllanthus amarus (Euphorbiaceae) possesses activity against hepatitis B virus and related hepadnaviruses. One such activity, the inhibition of endogenous hepadnavirus DNA polymerase, differed little between cultivatedP. amarus and plants collected from the wild. Inhibitory activity equivalent to that in wild plants was obtained from both shoots and roots sown at different times of the year in a subtropical region (Dade County, Florida, U.S.A.). Plant size and two levels of fertilization did not significantly affect activity. Plots were planted using a cellulose gel to evenly disperse the small seeds. Gel amendments used at sowing had no significant effect on the antiviral activity of harvested plants. Drip irrigation permitted successful cultivation during the dry season. Plastic mulch was used to control weeds.Phyllanthus amarus grows slowly, and reaches a maximum size and vigor at about 5–7 months after sowing. Under south Florida conditions, the greatest biomass ofP. amarus was produced when seeds were sown in mid-winter for a summer harvest. With weed control by the mulch, water and fertilization via the drip irrigation, six and a half month old plants (from sowing) reached an average dry weight of approximately 40 glplant when harvested in July or August.ResumenPhyllanthus amarus (Euphorbiaceae) posee actividades contra el virus hepatitis B y otros hepadnavirus relacionados. Una actividad específica, la inhibición de la polimerasa DNA endógena de los hepadnavirus, no varió entre las plantas cultivadas y colecciones de plantas silvestres. Un nivel de actividad inhibitoria equivalente a plantas silvestres se obtuvo de vástagos y raices de plantas sembradas en diferentes epocas del ano en una región subtropical (Dade County, Florida, EE UU). El tamaño de la planta y dos niveles de abonamiento no tuvo efecto significativo sobre la actividad. Las parcelas fueron sembrados usando un gel de celulosa para dispersar homogéneamente las pequeñas semillas. Diferentes enmiendas de gel al sembrar no tuvieron efecto sobre la actividad antiviral de las plantas cosechadas. El uso de riego por goteo permitio el cultivo exitoso durante la temporada seca. Se usó plástico para controlar las malezas. El crecimiento deP. amarus es lento, y llega asu máximo tamaño y vigor entre los 5 y 7 meses después de la siembra. Bajo las condiciones del sur de la Florida, se produjo la máxima bíomasa cuando se sembró en medio del invierno para cosechar en el verano. Por medio del uso de plástico para controlar malezas, riego por goteo y la fertilizatión a través del riego, el promedio de peso seco por planta de seis meses y medio de edad fue de 40 g al cosecharlas en julio o agosto.

Factors affecting germination and stand establishment ofphyllanthus Amarus (Euphorbiaceae)

Interest inPhyllanthus amarus (Euphorbiaceae) has been generated by reports of antiviral activity and wide usage in traditional medicine. Attempts at cultivation resulted in poor stands. The objectives of these studies were to determine the effects of light, storage temperature, age of seeds, time ofdehiscence, and a scarification procedure on the germination ofP. amarus. Seeds ofP. amarus require light to germinate, and thus should not be covered at sowing. Freezing did not significantly affect the germination of dry seeds compared to seeds stored at ambient room temperature or higher, but storage at 10°C was deleterious. Percent germination was typically less than 50% and significantly decreased with time. Germination of freshly harvested seeds was slower than older seeds. Seeds from the first capsules to dehisce had a higher percent germination. A scarification procedure rendered seeds inviable. These results helped explain poor stands seen infield plots. In a previously planted plot, the re-established stand by natural reseeding was equivalent to that following intentional reseeding procedures.RésuméSegún se ha informado el interés en cuanto a Phyllanthus amarus (Euphorbiaceae) es debido a su actividad antiviral y su uso en la medicina tradicional. Al intentar su cultivo, la post-germinación fue menos de lo esperado. Los objetivos de estos estudios fueron probar los efectos de la luz, la temperatura de almacenamiento, la edad de las semillas, el periodo de la apertura de las cápsulas conteniendo las semillas y un procedimiento de escarificación en la germinación deP. amarus. Las semillas deP. amarus necesitan luz para germinar; es por eso que no se las debe cubrir al sembrar. Temperaturas de congelamiento no afectaron significativamente la germinación de las semillas secas al compararlas con las semillas mantenidas bajo temperatura ambiental o más aha, pero sin embargo el almacenamiento a 10°C sí afectó severamente la viabilidad. El porcentaje de viabilidad por lo general fue bajo, generalmente menos de 50%, y disminuyó con el tiempo. Las semillas nuevas germinaron más lentas que las semillas más viejas. Las primeras semillas que salieron de las cápsulas mostraron un mayor porcentaje de germinación. El procedimiento de escarificación que seprobó dio semillas inviables. Estos resultados ayudan a explicar la baja post-germinación observada en el campo. En terrenos anteriormente sembrados, la post-germinación de siembra natural fue equivalente a los procedimientos intencionales de siembra.

Usage and bioassays in Phyllanthus (Euphorbiaceae): a compilation III. The subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and a complete list of the species cited in the three-part series

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four papers, including (in Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part III) covers the subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and also includes a list of the species cited in this three-part series.