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Mayapple: A review of the literature from a horticultural perspective

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Species of the Podophyllum genus contain important anti-cancer compounds: podophyllotoxin, -peltatin, and -peltatin. A Podophyllum species found in India, Podophyllum emodi Wall. (Syn. P. hexandrum Royale, Berberidaceae), has been over-harvested to meet pharmaceutical industry demand. The Indian species P. emodi Wall, is considered an endangered species because the compound is found in the roots and whole plant was harvested. On the other hand, American Mayapple is a rhizomatous herbaceous perennial found in the wild throughout North America from Quebec and Minnesota to Florida and Texas and source of compound is leaves. Commercial plantings of mayapple have the potential to reduce harvest pressure on this species. In a review of the scientific literature, few references about commercial production or field establishment were found. To begin to understand mayapple as a horticultural crop, this review presents a summary of the plant's botany, climate and soils, growth and development, sexual and asexual propagation, pests and diseases, and medicinal uses. Sixty references are listed.
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Journal of Medicinal Plants Research Vol. 5(7), pp. 1037-1045, 4 April, 2011
Available online at http://www.academicjournals.org/JMPR
ISSN 1996-0875 ©2011 Academic Journals
Review
Mayapple: A review of the literature from a horticultural
perspective
Muhammad Maqbool
Department of Horticulture, University College of Agriculture, Bahauddin Zakariya University, Multan, Pakistan.
E-mail: maqboolmsu@hotmail.com.
Accepted 5 January, 2011
Species of the Podophyllum genus contain important anti-cancer compounds: podophyllotoxin, -
peltatin, and -peltatin. A Podophyllum species found in India, Podophyllum emodi Wall. (Syn. P.
hexandrum Royale, Berberidaceae), has been over-harvested to meet pharmaceutical industry demand.
The Indian species P. emodi Wall, is considered an endangered species because the compound is
found in the roots and whole plant was harvested. On the other hand, American Mayapple is a
rhizomatous herbaceous perennial found in the wild throughout North America from Quebec and
Minnesota to Florida and Texas and source of compound is leaves. Commercial plantings of mayapple
have the potential to reduce harvest pressure on this species. In a review of the scientific literature, few
references about commercial production or field establishment were found. To begin to understand
mayapple as a horticultural crop, this review presents a summary of the plant’s botany, climate and
soils, growth and development, sexual and asexual propagation, pests and diseases, and medicinal
uses. Sixty references are listed.
Key words: American mayapple, Podophyllum peltatum, Podophyllum emodi, Podophyllum hexandrum,
podophyllotoxin, -peltatin, -peltatin, rhizome, field establishment.
INTRODUCTION
The American Mayapple (P. peltatum) has become well
known for containing anti-cancer, anti-viral, and anti-
mitotic compounds (Meijer, 1974; Bedow and Hatfield,
1982; Canel et al., 2000b). These compounds are lignans
found in podophyllin, a term used to describe ethanolic
extracts of the American Mayapple and other
Podophyllum species. Three lignans have been identified
with health-related activity: podophyllotoxin, -peltatin,
and -peltatin (Figure 1). Podophyllotoxin has anti-
cancer, anti-mitotic and immunostimulatory activities
(Kaplan, 1942; Loike et al., 1978; Pugh et al., 2001)
whereas - and -peltatin have purgative (laxative)
properties. Native Americans and other indigenous
people used these plants as purgatives and also for
treatment of genital warts and skin cancers (Krochmal et
al., 1969). It is important to mention, however, that all
parts of the mayapple plant are considered poisonous to
humans with the only exception thought to be the ripe
fruit.
P. peltatum and P. emodi are the major sources of
podophyllotoxin. Podophyllotoxin is used as the precursor
in the manufacture of the semi-synthetic derivatives
etoposide, teniposide, and etopophos. The United States
Food and Drug Administration approved these drugs for
the treatment of testicular and small cell lung cancer
(Foster, 1989). Since 1995, when the patent covering
these uses expired, the National Cancer Institute has
listed 190 clinical trials for etoposide in new cancer
therapies or as positive control (Ajani et al., 1999; Holm
et al., 1998; Ekstrom et al., 1998). Another compound,
known as CPH 82, is a semi-synthetic derivative of
podophyllotoxin and is in its third phase of clinical trials
for the treatment of rheumatoid arthritis (Lerndal and
Svensson, 2000). A highly purified preparation of
podophyllotoxin has been tested for the treatment of
psoriasis (Lender and Rosen, 1988). P. peltatum and P.
emodi are not the only sources of podophyllotoxin.
Similar lignans have been found in the roots and
1038 J. Med. Plant. Res.
Podophyllotoxin -Peltatin -Peltatin
Figure 1. Structures of three health related lignans found in mayapple.
rhizomes of P. pleianthum (Jackson and Dewick, 1985)
and P. versipelle (Broomhead and Dewick, 1990a). Yu et
al. (1991) isolated a new podophyllotoxin–type lignan, 4´-
demethylisopodophyllotoxin, from Dysosma versipellis
var. Tomentosa. Podophyllotoxin and related aryltetralin
lignans have also been reported in various genera such
as Linum, Hyptis, Teucrium, Nepeta, Jeffersonia,
Thymus, Thuja, and Juniperus (Broomhead and Dewick,
1990a; (Broomhead and Dewick, 1990b; Konuklugil,
1996; Kuhnt et al., 1994; Muranaka et al., 1998; San
Feliciano et al., 1989a; San Feliciano et al., 1989b).
Though podophyllotoxin has been reported in plants of
these genera, quantitative data is limited.
Commercial plantings will provide a consistent and high
quality product to the drug industry and may provide
opportunities for agricultural producers of high-value
specialty products. To meet pharmaceutical industry
demand, P. emodi is still harvested from the wild.
However, it is difficult to collect from the wild and to
properly supervise the harvest of a high quality product.
Furthermore, excessive harvest has resulted in a
significant decline of wild populations. Such decline has
been reported in India with P. emodi now considered an
endangered species (Foster, 1993). Commercial
plantings of mayapple have the potential to reduce
harvest pressure on this endangered species.
Findings reported by National Center for Natural
Products Research (NCNPR) at the University of
Mississippi support the potential of establishing field
plantings of mayapple for the commercial production of
podophyllotoxin. It was found that leaves of P. emodi
were a poor source of podophyllotoxin compared to the
traditional source from the rhizomes. In contrast, leaves
of P. peltatum contain relatively high levels of
podophyllotoxin (Canel et al., 2001; Moraes et al., 2001).
Podophyllotoxin content of P. peltatum leaves is lower
than that of P. emodi rhizomes but still enough to
consider P. peltatum leaves a potential commercial
source of the compound. NCNPR and USDA increased
the potential of using leaves as a commercial source by
patenting an easy and efficient water-based method to
extract lignans from mayapple tissue (Canel et al., 2000a;
Moraes et al. 2002).
BOTANY AND CLASSIFICATION
Common names for the American Mayapple are
Mandrake, Wild Lemon, Raccoon Berry, Wild Jalap,
Devil’s–apple, Hog Apple, Indian Apple, and Umbrella
Plant (Cornell Univ, 1976; Reader’s Digest Assoc., 1986).
In the southern U.S., it is often referred to as “Maypop.”
Mayapple is an erect herbaceous perennial to 2 feet
in height, with a solitary or forked stem topped with one
or two leaves that are palmately lobed and up to 12
inches wide (Figure 2a). The solitary, creamy white,
fragrant flowers vary from 2 to 3 inches across, and arise
in the v-shaped axil of the stem (Figure 2a). The
rhizomes grow close to the soil surface (Figure 2b).
Individual plants, or shoots, arise at each node of the
underground rhizome and form dense clonal communities
(Figure 2c). Mature fruits are yellow, 1½ to 2½ inches
long, ovoid and may contain up to 25 seeds, each in a
mucilaginous aril (Figure 2d). The seeds are dark brown,
oval, flattened, and tapered at the apex, with a dull brown
rough surface and an oval, inconspicuous hilum. As the
seeds age, they become wrinkled (Krochmal et al., 1974).
Pearce and Thieret (1993) described mayapple fruit as
green-yellow to yellow when ripe (mid to late summer),
many seeded, and about the size and shape of a hen’s
egg. They reported an average weight of 13.4 g per fruit,
with 34.3% of the total weight being made up of seeds
Maqbool 1039
Figure 2a. Mayapple plant showing a solitary flower on a forked stem.
Figure 2b. Mayapple rhizome.
and attached arils. According to their findings mayapple
fruit contains extremely high water contents (94.7%),
higher even than watermelon (92%), grapefruit (91%),
melons (90%) or papaya (89%).
Fifteen species of the Podophyllum genus have been
described, but most are now placed taxonomically in the
related genera of Dysosma and Sinopodophyllum. The
Podophyllum genus is placed in the Berberidaceae
family. Species in the Podophyllum genus can be difficult
to research because they have been moved from genus
to genus and have at times been renamed. For example,
P. emodi and P. hexandrum are synonyms. Older
manuscripts often refer to this species as P. hexandrum.
In addition, P. plieanthum and Dysosma plieantha are
synonyms. Chinese scientists separated the
Podophyllum genus from the Berberidaceae family and
created a new family, Podophyllaceae (Foster, 1989).
Much confusion still remains in that there are many
1040 J. Med. Plant. Res.
Figure 2c. Mayapple colony in the wild.
Figure 2d. Mayapple fruit.
suggestions for further rearrangements. For example,
one suggestion is to place the Podophyllum genus in a
subfamily, Podophylloideae (Heywood, 1993).
BIODIVERSITY IN POPULATIONS
Finding by NCNPR showed that podophyllotoxin content
of P. peltatum leaves varied by location (Moraes et al.,
2001). About 17 wild populations were sampled from
Illinois, Indiana, Missouri, North Carolina, Ohio and West
Virginia (Figure 3) with podophyllotoxin content ranging
from 1.1 to 56.0 mgg-1. Eleven wild populations were
also sampled from Lafayette County, Miss. with
podophyllotoxin content ranging from almost 0 to 23.6
mgg-1. After two years of cultivation in plastic containers,
accessions with low podophyllotoxin content remained
low while accessions with relatively high podophyllotoxin
Maqbool 1041
Map showing distribution of
mayapple in North America
Figure 3. Distribution of mayapple (Podophyllum peltatum) in North America (USA and
Canada). Adopted from USDA database.
content remained high. These results indicate that
podophyllotoxin content is a stable genetic trait rather
than an effect of location or environment. These results
also indicate that mayapple leaves harvested from the
wild may—or may not—produce acceptable yields of
podophyllotoxin. The implications of this research
indicate that genetic improvement of mayapple may be
possible by identifying, propagating, and genetically
manipulating high-yielding genotypes. In this same study,
a negative correlation was found between
podophyllotoxin content and peltatin content. Genotypes
with higher levels of podophyllotoxin had lower levels of
-peltatin and -peltatin. Similarly, Zheljazkov et al.,
(2009) collected American mayapple leaves from 37
mayapple colonies across 18 states indicated a
significant variation in podophyllotoxin, -peltatin, and -
peltatin content and the presence of chemotypes. Overall,
the concentrations of podophyllotoxin, -peltatin, and -
peltatin in the collected accessions ranged from below
detectable levels to 45.1, 47.3, and 7.0 mg·g–1 dry weight,
respectively. They also classified American mayapple
accessions into seven groups:
1) With very high concentration of podophyllotoxin
(greater than 20 mg·g–1) and no - or -peltatin;
2) High podophyllotoxin (greater than 10 mg·g–1) and no
-peltatin but trace amounts of –peltatin;
3) Medium podophyllotoxin (1 to 10 mg·g–1) and no - or
-peltatin;
4) Low podophyllotoxin (0.05 to 1 mg·g–1) and high -
peltatin;
5. Trace amounts of podophyllotoxin and high
concentration of -peltatin and -peltatin;
6. High -peltatin and trace amounts of podophyllotoxin or
–peltatin; and
7. High –peltatin and no podophyllotoxin or -peltatin.
The results from this study may contribute toward the
development of high podophyllotoxin containing varieties
of American mayapple and the development of a new
cash crop for farmers.
Sultan et al. (2010) narrated that that RAPD and
chemical markers are very useful tools to compare the
genetic relationship and pattern of variation among
different populations of Podophyllum hexandrum
collected from high altitude regions of North Western
Himalayas declared an endangered medicinal plants.
It has been observed that Podophyllotoxin and total
lignin contents of American mayapple at 0% shade were
significantly greater than those at 80% shade and shade
did not affect -peltatin content. However, contents of -
peltatin were greatest at 0% shade compared to the other
three shade treatments (Cushman et al., 2005). Crushing
injury drastically improved podophyllotoxin content of
1042 J. Med. Plant. Res.
American mayapple leaves when dried at 40°C within 24
h of harvest (Bedir et al., 2006). In contrast,
podophyllotoxin content was greatly reduced when dried
at room temperature at 15% relative humidity and 24°C.
However, Podophyllotoxin content was stable, with no
significant changes over time, when leaves were dried,
ground, and stored under different conditions for up to 60
days.
SOIL AND CLIMATE
P. peltatum is found in the wild, often in large colonies in
eastern North America from Quebec and Minnesota to
Florida and Texas (Meijer, 1974; Pearce and Thieret,
1993). The wide distribution of mayapple in the wild
shows that it can survive under a wide range of
conditions from the extreme below-zero winter
temperatures of northern climates to the high summer
temperatures of southern climates. Krochmal et al. (1974)
analyzed the soil of a typical forest mayapple habitat
located in the Daniel Boone National Forest, Jackson
County, Kentucky. The soil was defined as a typical
southern Appalachian cove soil with alluvial and colluvial
material. The analysis showed mineral element and
organic matter (OM) contents of 0.4-1.9 ppm P, 200-540
ppm Ca, 80-120 ppm Mg, 125-300 ppm K, 0.27-2.57 %
C, and 0.46-3.75 % OM. Soil samples were recently
collected from local mayapple populations in Lafayette
County, Miss. in the fall of 2000 and analyzed for soil
texture and mineral element (unpublished data). It was
found that these populations were growing in silt loam,
sandy loam, and loamy sand soils. The analysis showed
mineral element and OM contents of 4-25 ppm P, 53-430
ppm Ca, 15-109 ppm Mg, 21-85 ppm K, 102-212 ppm S,
and 1.41-2.94 % OM. The soils tested for pH in a range
of 4.7 to 6.0. According to Zheljazkov et al., (2009)
American mayapple was found to grow on various soil
types with a range of soil pH (4.6 to 7.6) and dissimilar
concentrations of phytoavailable soil nutrients. Tissue
zinc concentration was positively correlated to
podophyllotoxin, whereas soil and tissue phosphorus was
positively correlated to the concentration of -peltatin
GROWTH AND DEVELOPMENT
Plants grown from seed remain juvenile for 4 to 5 years.
During this time, shoots arise annually from a bud located
on the terminal end of an underground vertical stem.
After 4 to 5 years, plants then produce a single horizontal
rhizome. The rhizome continues to develop annually,
producing elongated internodes between nodes. Each
node is a complicated structure composed of a highly
compressed stem, a main bud that develops into the next
season’s growth, and many minor buds that any one of
them can develop and continue rhizome growth. Roots
develop predominately from rhizome tissue at the base of
the node. Roots can arise from the internodal tissue near
the terminal bud of the rhizome. For a review of
mayapple morphology, including seedlings, rhizomes,
nodes, and elongated internodes (Foerste, 1884; Holm,
1899).
A single shoot arises from each node of the rhizome.
Shoots are either asexual, producing a single vegetative
stem and leaf, or sexual, producing a single stem, two
leaves, and a solitary flower in a fork formed by the
petioles of the two leaves. A complex relationship of
environmental signals exists that determines whether any
particular node produces a sexual or asexual shoot. Prior
history of the node, whether it produced a sexual or
asexual shoot in the previous year, also greatly
influences the sexual or asexual status of the shoot. For
a thorough discussion of factors affecting not only sexual
or asexual shoot status but also rhizome branching, see
Geber et al. (1997).
Both types of growth, asexual and sexual, emerge in
early spring before trees produce leaves and then
senesce by midsummer. Watson and Lu (1999) observed
that several factors might influence the timing of shoot
senescence such as the current or future reproductive
status of the shoot, the past and current vigor of the
rhizome system, the genotype, and the environment to
which the plant was exposed. For example, sexual
shoots senesced later than asexual shoots. Sexual
shoots that produced fruit senesced later than sexual
shoots without fruit. Shoots arising from large rhizomes
senesced later than those from small rhizomes.
According to de Kroon et al. (1991) shoots that senesce
later produce longer and heavier rhizomes. Landa et al.
(1992) showed with 14C tracers that photoassimilates
were translocated to roots, rhizomes, and nodes at the
onset of leaf senescence. The stored carbohydrates are
then translocated to newly developing growing points the
following spring.
To explore the domestication of this species, Cushman
et al. (2005) harvested mayapple rhizome segments from
the wild and transplanted to raised beds using two mulch
types (pine bark or wheat straw), two depths of mulch (0
or 5 cm) and two planting depths (0 or 5 cm) of rhizome
segments and found that rhizome segments planted 0 cm
deep and covered with wheat straw mulch consistently
produced fewer shoots with less leaf area and dry mass
compared to other treatment combinations. They
recommended either bark or straw mulch for the purpose
of establishing field plantings in full sun as long as
rhizome planting depth is 5 cm.
SEXUAL PROPAGATION
The American Mayapple is described as self-
incompatible. Many researchers believe colonies of
mayapple in the wild are clonal populations comprised of
one genotype (Laverty and Plowright, 1988; Swanson
and Sohmer, 1976a). It is thought that an entire colony
may come from a single seedling. The seedling
eventually develops into a colony of plants with identical
genes. In contrast to this view, Policansky (1983) found
mayapple colonies comprised of more than one
genotype.
Laverty and Plowright (1988) observed a significant
increase in mayapple fruit and seed production when
populations of mayapple and Pedicularis canadensis
were located adjacent to each other and when insect
pollinators regularly visited both populations. This
increase in mayapple seed set by cross-pollination was
also observed with species of the genus Bombus
(Swanson and Sohmer, 1976b). They observed that intra-
population crosses in mayapple resulted in lower seed
set than inter-population crosses, thus adding to the
evidence that mayapple is at least partially self-
incompatible. Whisler and Snow (1992) found a 26-fold
increase in seed set by hand pollination in mayapple
compared to natural levels of pollination during one year
of observation and a 5-fold increase in the next. Rust and
Roth (1981) described that improper pollination is the
most important factor affecting seed set. They also
described other factors that could affect seed set, such
as flower abortion, immature fruit abortion, and failure of
fruits and seeds to be transported away from clonal
populations.
Krochmal et al. (1974) were unable to germinate
mayapple seeds even after finding 88 % of them viable
with a tetrazolium test. Badhwar and Sharma (1963) were
unsuccessful in germinating seeds of P. emodi even after
testing a wide variety of treatments to increase
germination. However, they found that seeds sown with
fresh mayapple fruit pulp germinated in 9 to 10 months.
Similar results were found in P. peltatum (Meijer, 1974).
Rust and Roth (1981) reported that turtle-ingested seeds
germinate faster and have higher probability of success
than non-ingested seeds of mayapple.
Asexual propagation
Troup, an investigator from India, was quoted as saying
that mayapple plants raised from rhizome cuttings “would
probably take at least 12 years to produce fair-sized
marketable rhizomes” (Badhwar and Sharma, 1963). The
investigator was also quoted as saying that plants raised
from seedlings would take even longer. Another
investigator, Chopra, was quoted as saying that
“rhizomes are fit to be collected for the market when they
are 2 to 4 years old.” Badhwar and Sharma (1963)
themselves experimented briefly with P. emodi rhizome
cuttings that were trimmed to ½ to 1 inch in length. From
34 to 98 % of the cuttings sprouted when planted from
May to July. Best results were obtained with cuttings
planted from late June to early July and with cuttings
Maqbool 1043
taken from the youngest portion of the rhizome.
It was narrated that fall planted propagules produced
greater leaf area and dry mass than spring or summer
planted propagules and Nt+N1 type of propagules
produced greater leaf area than Nx or Nt (Maqbool et al.,
2002; Cushman and Maqbool, 2005). Maqbool et al.,
(2004), further reported that two-node rhizome segments
of American mayapple performed better than one-node
propagules and segments chilled 60 days or longer
performed far better than those chilled for shorter
duration under greenhouse conditions.
Successful propagation of P. peltatum using in vitro
techniques has been reported (Moraes-Cerdeira et al.,
1998). Rooted buds and rooted plantlets were produced
from micro-propagated rhizome terminal buds and it was
found that rooted buds acclimated more readily to in vivo
conditions than rooted plantlets. In 2004, Moraes et al.,
found that survival of P. peltatum plantlets from In vitro
propagation was higher in a medium containg non-sterile
soil (NS)–sand (2:1 v/v) substrate than in Miracle–Gro
potting mix®-sand (2:1 v/v) with or without inocula of
arbuscular mycorrhiza (AM). Plantlets inoculated with
Entrophospora colombiana had a superior survival rate
(73%) than plantlets inoculated with Glomus mosseae,
Gigaspora ramisporophora or Scutellospora fulgida
(57%). Ex vitro G. ramisporophora inoculated plants
yielded more podophyllotoxin and related lignans than
the control, non-inoculated plants. Similar observation
was also reported by Kapoor et al. (2008).
PESTS
Mayapple is susceptible to rust. The causal organism is
Puccinia podophylli and it produces a non-systemic
infection that has two generations per year. The initial
infection occurs as shoots emerge in the early spring via
contact with soil that contains overwintering teliospores
(Whetzel et al., 1925). Bright orange lesions (aecia)
develop on leaves within two weeks. Aecia produce
airborne aeciospores that then re-infect the mayapple
leaves. Black lesions (telia) develop from which
overwintering teliospore are produced. The first
generation is the most harmful, since plants are damaged
early in their growth cycle. There is less damage during
the second generation, since telia development occurs in
the late spring just before normal leaf senescence.
According to Parker (1988), the demographic impact of
the disease in most mayapple colonies is minimal
because the plant has an effective morphological defense
that minimizes contact between spore-contaminated soil
and the emerging shoot in spring. Parker (1989)
observed however, higher levels of P. podophylli infection
on some non-native mayapple genotypes than on native
genotypes. Septotonia podophyllina infects mayapple, as
well as species of poplar and Salix. Large spots form on
leaves and the infection leads to premature leaf drop.
1044 J. Med. Plant. Res.
Pustules (sporodochia) with hyaline conidia appear,
allowing spread of the fungus to neighboring leaves and
plants (Gremmen, 1987).
Mayapple is poisonous to humans, but it is also thought
to produce toxins that prevent insect feeding. Faeth
(1978), however, identified three species of Lepidoptera
insects that were capable of detoxifying or metabolizing
these compounds. The larvae were able to mature to
adulthood when placed on live mayapple plants in the
laboratory.
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... The placement of this small genus within the family Berberidaceae was the subject of investigations by a few authors, and different classifications have been proposed [18][19][20]. Despite of these studies, the phylogenetic relationship between the genera within the Berberidaceae needs to be further investigated [21,22]. Meanwhile, some issues regarding the botanical classification of Podophyllum remain to be resolved. ...
... Etoposide (21) and teniposide (22) stabilize the covalent DNA-enzyme ternary complex inhibiting the catalytic activity of topoisomerase II irreversibly. These compounds act in late S or G2 phases of the cell cycle, preventing the DNA repair by topoisomerase II [61,62,69,70]. ...
... Several mechanisms of the antiviral action of lignans have been proposed [64,65]. Bedows and Hatfield [72] showed that podophyllotoxin (1), deoxypodophyllotoxin (13), and β-peltatin (22) were active against the measles virus (RNA virus) and herpes simplex virus type I (HSV-I, DNA virus). They proposed that this activity is likely due to the disruption of cellular microtubules interfering with viral replication. ...
Chapter
Podophyllums have been used extensively as medicinal plants and are part of the folklore in Asian and American cultures. Their use dates back to the Chinese culture of 2,000 years ago where they were used as an antitumor drug. The resin podophyllin was first recommended as an antiviral agent and provided clues for new applications. The most important secondary metabolite isolated from the rhizomes and roots of the Podophyllum species is podophyllotoxin and its related lignans. This lignan is the precursor of the semisynthetic drugs etoposide, teniposide, and etopophos, which are clinically used in the therapeutic treatment of cancer. Moreover, other derivatives have shown different types of biological activity. With an increasing worldwide market for anticancer drugs, supplies of podophyllotoxin for the pharmaceutical industry are under great pressure. As the chemical synthesis of podophyllotoxin is not economic on a commercial scale, supplies are still obtained from wild populations of Podophyllum. Concern has been expressed about the shortage of Podophyllum which is now an endangered species due to overexploitation and a lack of cultivation. Attempts to increase plant yields have improved through in vitro technology while the production of podophyllotoxin will require further studies. This chapter provides an overview of the Podophyllum species and its lignans. Podophyllum biotechnology still presents challenges to be overcome and some of these are, in part, discussed in this chapter.
... The placement of this small genus within the family Berberidaceae was the subject of investigations by a few authors, and different classifications have been proposed [18][19][20]. Despite of these studies, the phylogenetic relationship between the genera within the Berberidaceae needs to be further investigated [21,22]. Meanwhile, some issues regarding the botanical classification of Podophyllum remain to be resolved. ...
... Etoposide (21) and teniposide (22) stabilize the covalent DNA-enzyme ternary complex inhibiting the catalytic activity of topoisomerase II irreversibly. These compounds act in late S or G2 phases of the cell cycle, preventing the DNA repair by topoisomerase II [61,62,69,70]. ...
... Several mechanisms of the antiviral action of lignans have been proposed [64,65]. Bedows and Hatfield [72] showed that podophyllotoxin (1), deoxypodophyllotoxin (13), and β-peltatin (22) were active against the measles virus (RNA virus) and herpes simplex virus type I (HSV-I, DNA virus). They proposed that this activity is likely due to the disruption of cellular microtubules interfering with viral replication. ...
Chapter
Podophyllums have been used extensively as medicinal plants and are part of the folklore in Asian and American cultures. Their use dates back to the Chinese culture of 2,000 years ago where they were used as an antitumor drug. The resin podophyllin was first recommended as an antiviral agent and provided clues for new applications. The most important secondary metabolite isolated from the rhizomes and roots of the Podophyllum species is podophyllotoxin and its related lignans. This lignan is the precursor of the semisynthetic drugs etoposide, teniposide, and etopophos, which are clinically used in the therapeutic treatment of cancer. Moreover, other derivatives have shown different types of biological activity. With an increasing worldwide market for anticancer drugs, supplies of podophyllotoxin for the pharmaceutical industry are under great pressure. As the chemical synthesis of podophyllotoxin is not economic on a commercial scale, supplies are still obtained from wild populations of Podophyllum. Concern has been expressed about the shortage of Podophyllum which is now an endangered species due to overexploitation and a lack of cultivation. Attempts to increase plant yields have improved through in vitro technology while the production of podophyllotoxin will require further studies. This chapter provides an overview of the Podophyllum species and its lignans. Podophyllum biotechnology still presents challenges to be overcome and some of these are, in part, discussed in this chapter.
... Mature fruits are of yellow colour, between 3.5 and 6.5 cm long, of ovoid shape and may contain up to 25 brown, flattened and rough seeds, each in an aril (Krochmal et al. 1974). It is significant to mention that all parts of P. peltatum are poisonous except for the ripe fruit (Maqbool 2011). Main anti-cancer chemical source in P. peltatum are leaves (Maqbool 2011). ...
... It is significant to mention that all parts of P. peltatum are poisonous except for the ripe fruit (Maqbool 2011). Main anti-cancer chemical source in P. peltatum are leaves (Maqbool 2011). Well known compounds of this species are podophyllotoxin and alpha and beta peltanin. ...
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Full-text available
The purpose of this paper is to present a review of highly developed medicinal usages of plants in the treatment of cancer. In the last decades, the cancer treatment has been included in this range of plant use, due to plant active substances. Active substances or secondary metabolites are generally known for their widespread application. When it comes to the cancer treatment, these substances affect the uncontrolled cell division. Therefore, the plants which are the source of these substances are proved to be irreplaceable in this field of medicine. This paper deals with some of the most significant plants well known for their multiple aspects of beneficial medicinal influence. The group of the plants described is comprised of the following species: Taxus brevifolia (Taxaceae), Catharanthus roseus (Apocynaceae), Podophyllum peltatum (Berberidaceae), Camptotheca accuminata (Cornaceae), and Cephalotaxus harringtonia (Cephalotaxaceae). The comprehensive description of the plants in this paper includes the morphological characteristics, the features and the representation of the molecular structures of active substances, the particular influence that these active substances have and the general importance of the substances as seen from the aspect of cancer treatment mostly with reference to the impacts on cell cycle.
... The paradox is that now the major suppressors of the indigenous knowledge are not the westerners but the local people with the western education. Today a number of plants around the globe are highly regarded for medicinal value, among them are; Mayapple or American mandrake, or mandrake (Podophyllum peltatum Linnaeus) (Maqbool 2011) found in American, Cape bush-willow (Combretum caffrum) found in South African and Pacific Yew or Canadian Yew (Taxus brevifolia) found in Canada have anticancer properties and some research may be going on to make medicine from them (Srivastava et al. 2005). However, very little is going on in Kenya to value add herbs like Red Stinkwood (Prunus africana) that is also reputed to have anticancer properties. ...
Chapter
Through the lens of a 16-year-old Nigerian secondary school student, this case study illustrates the human development and education crisis in Nigeria where the education system (represented by the private education sector) is focused on developing citizens for “global citizenship” but fails to prepare young Nigerians to learn about themselves as cultural-historical beings and agents for local and continental leadership. Although the school highlighted in this study is fictional, the experiences presented in the case are real. The case study was developed based on several research projects on private schools in Nigeria and my own personal schooling and advocacy experience in Nigeria. Focusing on the Magnum Prep Secondary School (MPSS) (pseudonym), the case highlights that the global citizenship curriculum measures its success based on the number of students who gain admission and attend Western universities. This pursuit is achieved by immersing the students in a colonial curriculum that upholds Western standards and values as the epitome of humanity. In effect, the curriculum denies these Nigerian students their humanity and right to equitably participate in the “global society” by not teaching them about their culture and history. Students’ voice is also stifled in this school. For example, even though, students had critical and constructive views about their curriculum, student programming and student life, their views were not considered. In so doing, the school system fails to develop Nigerians who are academically nuanced and embody the capacity and human agency to drive human development in the country.
... On the contrary, those root lines producers of 6-metoxipodophyllotoxin or betapeltatin, did not produce PTOX. Maqbool (2011) reported a similar relationship between plants of Podophyllum peltatum, collected in several sites along forests of USA, observing that those plants that produce PTOX do not produced β-peltatin, and contrariwise, those that produced β-peltatin do not produce PTOX 28 . ...
Article
Full-text available
Abstract. The wild shurb Hyptis suaveolens also known as “chia” was used as food and medicine since prehispanic times in Mexico, and nowadays is employed to treat several ailments. The anticancer lignan podophyllotoxin (PTOX) was recently reported in this plant, and its highest accumulation occurs in roots. This work reports the establishment of several lines of hairy root cultures of H. suaveolens producing PTOX. Three Agrobacterium rhizogenes strains (ATCC 15834, K599 + pGus-GFP+ , and ATCC 15834 pTDT) were used to induce hairy roots. The strain 15834 of Agrobacterium rhizogenes carrying its wild type Ri plasmid was transformed by introducing the TDT binary vector which contains the Tomato Threonin Deaminase gene. Hairy roots induced by infection with this new strain, showed red fluorescence; while those roots induced by infecting with K599+pGus-GFP+ showed green fluorescence as well as the expression of GUS gene. The transformed roots derived from explants infected with A. rhizogenes ATCC 15834 wild type exhibited the characteristic morphology of hairy roots. Fourteen root lines out of more than 100 lines obtained were selected. Cytotoxicity, fluorescence, GUS gene expression, growth rate and morphology, were used as selection criteria. Cytotoxic activity of different extracts obtained from these hairy roots against four cell lines of human carcinomas (KB, HF6, MC7 and PC3) was determined by the sulfurodamine B method. The cytotoxic values (IC50) of some root extracts were lower than 20 µg/mL, and some others even lower than 4 µg/mL. PTOX-like lignans, as β-peltatin and 6-methoxy podophyllotoxin (6-MPTOX), were identified by LC/MS
... Fig. (1) shows the morphological aspects of five plant species known by the remarkable medicinal properties concerning the production of the four valuable metabolites focused on this review. Galanthus woronowii, Papaver somniferum and Taxus brevifolia are sources of galanthamine, morphine and paclitaxel, respectively, while podophyllotoxin is the major secondary metabolite produced by Podophyllum emodi and Podophyllum peltatum plants [12][13][14][15][16]. The next sessions will focus on the total synthesis of galanthamine, morphine, paclitaxel and podophyllotoxin, substances that contribute for improving humans life quality. ...
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Nature is an irrefutable source of inspiration for the modern man in many aspects. The observation and understanding of nature have allowed the development of new materials, new sources of energies, new drugs etc. Specifically, natural products provide a great contribution to the development of new agents for the treatment of infections and antitumor agents. However, obtaining natural products directly from animals, fungi, bacteria, plants etc has been considered not enough to attend the high demand by pharmaceutical industries. In this regard, various strategies based on biotechnological processes or synthetic approaches have been developed. In this scenario the total synthesis can be undoubtedly a useful and powerful tool for obtaining higher amounts of natural products and/or structural modifications thereof. Herein, we emphasize successful examples of total synthesis of galanthamine, morphine, paclitaxel and podophyllotoxin - natural products approved as pharmaceuticals.
Chapter
Cancer is a serious public health problem that affects both men and women. Globally cancer is one of the leading causes of death. The risk factors associated with cancer development are categorized into intrinsic and extrinsic. The treatment modalities used in the treatment of cancer, such as chemotherapy, radiotherapy, surgery, and targeted therapies have adverse effects either during or after therapy. Currently, plant-derived anticancer compounds are being used in the treatment of various cancers. The variation of these compounds is according to their origin, general classification, and mechanism of action. Various studies have shown that anticancer agents of natural origin have fewer side effects when compared to traditional therapies. Anticancer agents of natural origins are a revolution in the field of cancer research and treatment as they are easy to isolate, cost-effective, and reliable to use. The advantage of anticancer agents of natural origin over synthetic ones and conventional therapeutic options is that their functions are selective and specific to a tumor undergoing treatment. This article is aimed at covering the success of plant-derived anticancer agents in the treatment of cancer, as well as their mechanism of action and the limitations associated with current therapeutic options.
Chapter
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The domination of “colonization shadow” may have reduced the manifestation of young indigenous technologies and innovations that with minimal value addition could help local communities overcome many challenges. Rediscovery of these technologies can bring about wealth and well-being to the local people who are also the inventors. Some of these technologies have either been suppressed or picked up by colonizers to the disadvantage of local inventors. This chapter discusses the useful, locally found technological resources that have not helped local communities but sometimes fetch millions of dollars elsewhere. This knowledge is expected to bring about rediscovery and decolonization so as to use the technologies to improve local lives. In this aspect decolonization is necessary in many sectors of the economy such as medicine which failed to take off from herbal- to industrial-based pharmaceutics. For instance, Kenya is the home of over 1100 species, many have medicinal value. While such herds are condemned at “home” as illegal herbal concoctions, they are glorified in other countries as medicine and food supplements. Today, many Kenyans import such medicine and food supplements at unaffordable prices as disease continues to bite. The conclusion is that there are a number of unexploited indigenous technologies and wealth that have remained dormant due to colonized minds and with little decolonization they can earn wealth that can increase wellness and improve livelihoods for the growing population in Kenya.
Chapter
Lignans are secondary metabolites synthesized by plants and exhibit a wide range of remarkable biological activities. In this chapter, the biosynthesis, metabolism, and the role of lignans in plant defense are extensively treated. All these details have been developed according to structures of main families and types in order to signify, when possible, the relationship between structures and biological activities . A special attention has been paid to podophyllotoxin and related substances due to their remarkable antitumoral properties.
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Podophyllotoxin is an aryltetralin lignan synthesized in several plant species, which is used in chemotherapies for cancers and tumor treatment. More potent semisynthetic derivatives of podophyllotoxin such as etoposide and teniposide are being developed and evaluated for their efficacy. To meet the ever increasing pharmaceutical needs, species having podophyllotoxin are uprooted extensively leading to the endangered status of selective species mainly Sinopodophyllum hexandrum. This has necessitated bioprospection of podophyllotoxin from different plant species to escalate the strain on this endangered species. The conventional and non-conventional mode of propagation and bioprospection with the integration of biotechnological interventions could contribute to sustainable supply of podophyllotoxin from the available plant resources. This review article is focused on the understanding of different means of propagation, development of genomic information, and its implications for elucidating podophyllotoxin biosynthesis and metabolic engineering of pathways. In addition, various strategies for sustainable production of this valuable metabolite are also discussed, besides a critical evaluation of future challenges and opportunities for the commercialization of podophyllotoxin.
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Author Institution: Department of Biological Sciences, University of Cincinnati
Article
Genotypic diversity is restricted within local colonies of mayapple (Podophyllum peltatum), due to extensive asexual reproduction. Transplant experiments were used to examine whether disease impact from a specialist fungal pathogen (Puccinia podophylli) was affected by the local frequency of host genotypes within colonies. In each of six large mayapple colonies, I measured infection intensity on 1) ramets replanted in their native colony (which were thus surrounded mostly by identical genotypes) and 2) transplants from two foreign colonies (surrounded by different genotypes). Disease incidence during the pathogen's first generation did not vary significantly between native (11% infected) and foreign host genotypes (6% infected). In the pathogen's second generation, significant variation in infection intensity occurred among ramets from different source populations. However, at five of the six transplant sites, mean infection intensity was higher on some nonnative plants (locally rare host genotypes) than on natives (locally common host genotypes). In this system, pathogen attack does not act in a frequency-dependent manner to promote local genetic diversity among hosts.
Article
Data on the content of podophyllotoxin, 5-methoxypodophyllotoxin, α- and β-peltatin in 26 plants belonging to the Linum genus are presented.
Article
Two new natural products, the acetates of epipodophyllotoxin and epipicropodophyllotoxin, were isolated from the lignan fraction of a n-hexane extract of the leaves of Juniperus sabina, along with deoxypodophyllotoxin, deoxipicropodophyllotoxin, (-)-deoxypodorhizon, β-peltatin A methyl ether and picropodophyllotoxin.
Article
The degree of physiological integration among compartments within modular plants and animals, as measured by the sharing of resources, can determine the response of such organisms to environmental variability. We used 14 C tracer methods to determine distribution patterns for photoassimilate in mayapple, Podophyllum peltatum L., a rhizomatous perennial herb with a simplified clonal architecture. Over half of the carbohydrate fixed during mid May, 1988, ended up in older segments of the rhizome system by early autumn, 1988. Roots, rhizomes and nodes along the entire length of the rhizome system all contained labelled material. By the following spring, 1989, there was a proportionate increase in label in the newly developing segment. Increases in activity in new roots and shoot between autumn and spring were accompanied by steep declines in activity in nearby rhizomes. Autoradiograms showed support of damaged rhizome branches by carbohydrate from attached, undamaged branches and the presence of carbohydrate fixed in 1988 throughout all structures of the developing 1989 shoot. No differences were seen in this study in the allocation patterns of systems with sexual or vegetative shoots. Mayapples exhibit high levels of physiological integration for carbohydrate compared to other, similar clonal perennials. This translocation may serve several functions, including storage and remobilization to support new growth, maintenance of an extensive root system and maintenance of a bud bank.
Article
Genotypic diversity is restricted within local colonies of mayapple (Podophyllum peltatum), due to extensive asexual reproduction. Transplant experiments were used to examine whether disease impact from a specialist fungal pathogen (Puccinia podophylli) was affected by the local frequency of host genotypes within colonies. In each of six large mayapple colonies, I measured infection intensity on 1) ramets replanted in their native colony (which were thus surrounded mostly by identical genotypes) and 2) transplants from two foreign colonies (surrounded by different genotypes). Disease incidence during the pathogen's first generation did not vary significantly between native (11% infected) and foreign host genotypes (6% infected). In the pathogen's second generation, significant variation in infection intensity occurred among ramets from different source populations. However, at five of the six transplant sites, mean infection intensity was higher on some nonnative plants (locally rare host genotypes) than on natives (locally common host genotypes). In this system, pathogen attack does not act in a frequency-dependent manner to promote local genetic diversity among hosts.
Article
The timing of leaf senescence may be imposed by the environment or controlled internally by the plant; the latter form of senescence we term endogenous senescence. Controls on the timing of endogenous senescence may reflect an evolutionarily derived compromise between the plant's carbon and mineral nutrient requirements. To examine the validity of this hypothesis, we examined the relationship between variation in mean shoot senescence time and demographic status in the long-lived perennial understory herb, the mayapple, Podophyllum peltatum. We found that mean shoot senescence time extends over a 30-d period, with the timing related to the recent history of the rhizome system, the demographic status of the current shoot, and the demographic status of the terminal bud on the extending rhizome axis (i.e., whether it will form a sexual or vegetative shoot in the following year). We found that (1) sexual shoots senesce later than vegetative shoots; (2) fruiting shoots senesce later than sexual shoots without fruits; and (3) shoots on rhizome systems where last year's rhizome segment was larger senesce later than those with a shorter ultimate rhizome segment. Of particular interest are our observations that (4) current shoots that give rise to larger new rhizome segments senesce later than those that give rise to smaller ones and (5) current shoots on rhizome systems that give rise to sexual new shoot buds senesce later than those that give rise to vegetative ones. We conclude that, in mayapple, the timing of endogenous shoot senescence is influenced by current and future reproductive status as well as the past and current vigor of the rhizome system. The patterns of relationship that we identify are consistent with the hypothesis that carbon rather than mineral nutrients is the resource most limiting mayapple growth. Significant differences in mean shoot senescence time also were detected among colonies and among years. These differences suggest the existence of genotype and environmental effects on the expression of endogenous leaf senescence time. It remains unclear whether variation in mean shoot senescence time, in and of itself, significantly affects the future demographic fate of rhizome systems.