ArticlePDF Available

Natural compounds discovered in Helleborus sp. (Ranunculaceae) with important medical potential,

Authors:
Central European Journal of Biology
* E-mail: maria.maior@ubbcluj.ro
Review Article
1Institute of Technology, Babeş-Bolyai University,
400294 Cluj-Napoca, Romania
2Department of Molecular Biology and Biotechnology,
Faculty of Biology, Babeş-Bolyai University,
400084 Cluj-Napoca, Romania
Maria Cornelia Maior1,*, Cristina Dobrotă1,2
Natural compounds with important medical
potential found in
Helleborus
sp.
1. Introduction
Current studies regarding species of Helleborus are
opening new ways to cure diseases using natural
compounds. Plants belonging to this group have long
been used in traditional medicine to treat various
conditions, such as edema, arthritis and ulcer. In the
Balkan area, Helleborus extracts have been used for
a long time in traditional medicine as painkillers or as
anti-inammatory remedies and in veterinary medicine
against infectious diseases. Several active compounds
including cardioactive glycosides, sterol saponosides,
ecdysteroids and γ-lactones have recently been isolated
from plants of this genus and shown to exert antioxidant,
anti-inammatory and antimicrobial effects. Anti-diabetic
and antitumoral properties were suggested, but further
investigations are required. Due to the scarcity of clinical
trials, there are few published reports on target-organ
toxicity or side effects. This review summarizes the latest
literature on the pharmacological, toxicological, and
clinical studies of Helleborus and its active compounds.
Advancing our understanding of the secondary
metabolite biosynthesis and ability to detect cell lines
with high level of active principles may positively impact
human health at a worldwide scale.
2. Biology and traditional use of
Helleborus spp.
Helleborus spp. (Ranunculaceae), or hellebore, is a
perennial herb native to Europe and Asia. The genus
comprises around 20 species. The underground parts
– rhizomes - containing starch granules and oleosomes
Cent. Eur. J. Biol. • 8(3) • 2013 • 272-285
DOI: 10.2478/s11535-013-0129-x
272
Received 12 June 2012; Accepted 29 November 2012
Keywords: Helleborus sp. • Phytochemicals • Secondary metabolites • Active compounds • Therapeutic potential • Anticancer properties
• Cytotoxicity • Immunomodulation
Abstract: Helleborus (family Ranunculaceae) are well-known as ornamental plants, but less known for their therapeutic benets. Over the
past few years, Helleborus sp. has become a subject of interest for phytochemistry, pharmacology and other medical research
areas. On the basis of their usefulness in traditional medicine, it was assumed that their biochemical prole could be a source
of metabolites with the potential to overcome critical medical issues. There are studies involving natural extracts from these
species which demonstrate that Helleborus plants are a valuable source of chemical compounds with great medical potential.
Some phytochemicals produced by these species have been separated and identied a few decades ago: hellebrin, degluco-
hellebrin, 20-hydroxyecdysone and protoanemonin. Lately, many other active compounds have been reported and considered
as promising remedies for severe diseases such as cancer, ulcer, diabetes and also for common medical problems such as
toothache, eczema, low immunity and arthritis. This paper is an overview of the Helleborus genus focusing on some recently-
discovered compounds and their potential for nding new drugs and useful biochemicals derived from these species.
© Versita Sp. z o.o.
M.C. Maior, C. Dobrotă
[1,2] accumulate the largest amount of metabolites. Most
of the hellebores are acaulescent (leaves and ower
stalks emerge from the rhizomes), only a few species
being caulescent. Leaves are pedate or palmate. The
color of the owers are given by the sepals which
remain on the ower long after fertilization; the petals
are reduced at the base of sepals. Hellebores bloom in
late winter or early spring, between February and April.
Roots, rhizomes and leaves are still used in traditional
medicine to treat humans and animals. Rhizome
extracts in particular have been reported as possessing
a broad spectrum of pharmacological and therapeutic
effects such as cardiotonic, abortive and sedative, as
well as having antioxidative, anti-inammatory and
antimicrobial activities.
There are old archives that mention species of
Helleborus in the Roman Empire and ancient Greece
[3,4]. Helleborus niger was used from antiquity until
Byzantine times to strengthen the heart and has a
positive effect on arteries and nerves [5]. Paracelsus
was prescribing to his patients “an elixirium for a long
life” made by dried leaves of H. niger [6]. There are
16 species of Ranunculaceae found in Renaissance
herbals that were used to treat malaria, 3 of them being
hellebores (H. foetidus, H. niger and H. viridis) [7]. In
Mt. Pelion, Greece, H. cyclophyllus is still used to treat
toothache. A decoction made of the entire plant or only
a piece from the underground part, held temporarily
in the mouth, could numb the entire mouth and stop
tooth pain. A tea made from leaves of H. cyclophyllus
was used by speakers to strengthen their voice [4]. In
Italy, roots of H. foetidus and H. bocconei were used
in the same way as in Greece to treat tooth pains [8]
and in Turkey, roots of H. orientalis were used for the
same purpose [9]. In the Montenegro region, eczema,
skin redness and itching [10] were treated using roots
of H. odorus. Peeled root of H. foetidus introduced into
the vagina, provoked hemorrhage followed by abortion
[8]. In the Italian Apennines, people are still using aerial
parts of H. foetidus to clean house chimneys, stoves,
wood ovens and as oil lamp wicks [11]. Even though
there are many species of Helleborus known as having
active principles, H. niger is the most widely used in
traditional medicine for a wide range of symptoms and
diseases [12]. In European folk medicine, H. niger was
used in expelling thick slime, as a remedy for sore joints,
as an emetic and laxant and for preparing sneezing
powders [13]. Alkaloids, glycosides and saponosides
found in species of Helleborus are considered to
be the constituents responsible for central nervous
system activity [14]. Tea from hellebore leaves, having
a sedative effect, was used in Danish folk medicine to
treat epilepsy and convulsions [15].
In traditional veterinary practice, different species
of Helleborus were used to treat infectious and
inammatory diseases. In Italy, H. foetidus and H. viridis
were used to treat many kinds of disease in pigs, cows,
sheep, mules and donkeys. Pneumonia was diagnosed
by inserting a piece of root in a subcutaneous cut or
in an incision on the ear of the pigs, with the animals
declared ill if the cuts swelled during the next day
[8,16]. In Sicily, H. bocconei subsp. siculus was used
to diagnose and to cure pneumonia in cattle [17,18].
H. odorus was used in a similar way in Serbia, with a
part of the stem being inserted in a hole in a sick sheep’s
ears [19]. Chronic inammatory diseases in pigs and
sheep [20] and infectious diseases [21] were treated
based on the anti-inammatory and antibacterial effects
of H. purpurascens roots, used as a transcutaneous
implantation. A decoction of H. foetidus was used to
clean wounds of animals when no better option was
available [11]. Crushed leaves of H. niger were used in
veterinary medicine in Pakistan as an antihelmintic [22].
H. foetidus is reported as having anti-insect
activity [23]. Many insects avoid hellebores, but some
species are using specic chemical compounds
contained in the plants to defend themselves against
predators. A furostanol saponin found in leaves of
H. foetidus and H. viridis was also found in the
hemolimph of Monophadnus sp. larvae at a more
than 200 fold higher concentration compared to plant
cells. It seems likely that this compound is involved in
the chemical defence of Monophadnus larvae against
potential insect predators [24].
3. Toxicity of Helleborus sp.
The use of H. orientalis extracts is mentioned in Homer’s
Odyssey [25]. Helleborus species are considered to
be toxic, but usually the poisonings are related to an
incorrect dosage [26]. Toxic features of hellebores are
determined mostly by the aglycons of cardiac steroids
but protoanemonin - a toxic γ–lactone, is also a toxic
compound.
Poisoning by cardioactive steroids is primarily
localized to the digestive system with severe
gastrointestinal irritation, vomiting and diarrhea [25,27].
Acute toxicity effects on the central nervous system
include lethargy, confusion and weakness that are not
caused by hemodynamic changes. Chronic toxicity
due to hellebore poisoning is difcult to diagnose and
less obvious. It could determine anorexia, weight loss,
neuropsychiatric disorders (confusion, drowsiness,
headaches, delirium, and hallucinations) and visual
disturbances. Cardiac manifestations of this kind of
273
Natural compounds with important medical
potential found in
Helleborus
sp.
poisoning include a multitude of cardiac dysrhythmias
[25].
Poisoning with protoanemonin occurs mostly in
animals and starts with salivation, vomiting, inammation
of the mouth and throat, abdominal pain that can be
followed by severe ulcerations of the mouth and damage
to the digestive and urinary systems. A severe poisoning
will present colored diarrhea and dark or blood stained
urine, unsteady gait, dizziness, impaired or lost vision.
Although fatal poisoning is rare, when it occurs death
is preceded by convulsions [28,29]. Protoanemonin has
also a toxic effect as a sub-epidermal vesicant, caused
by inactivation of enzymes containing SH groups [30,31].
4. Chemical analysis of Helleborus sp.
The rst reports of a general chemical composition of
hellebores date from 1943 when Karrer isolated for the
rst time from H. niger a cardiac glycoside named hellebrin
[32]. A few classes of compounds from Helleborus spp.
were identied and reported starting with the 1970s
[33,34], including: cardioactive glycosides (hellebrin,
degluco-hellebrin), steroidal saponins, ecdysteroids and
γ-lactones (protoanemonin).
4.1 Cardioactive glycosides
In plants, cardioactive glycosides were discovered in
angiosperms, both in monocotyledons and dicotyledons.
The therapeutic action of cardioactive glycosides
depends on the structure of the aglycone, and on the
type and number of sugar units attached. Two types of
aglycone are known: cardenolides (digitoxigenin from
Digitalis purpurea - C23 compounds), and bufadienolides
(hellebrigenin from Helleborus niger - C24 structures).
The lactone ring is ve-membered in cardenolides and
six-membered in the bufadienolides [35]. Cardenolides
are common substances and there are a few genera
that yield these compounds: Strophanthus, Convallaria
and Digitalis [35]. The bufadienolides are found in
Helleborus, Cotyledon, Kalanchoe, Scylla, Bowiea,
Homeria, Moraea, Bersama, Melianthus and Thesium.
Animal sources of bufadienolides include reies
(Photinus spp.), snakes (Rhabdophis spp.) and toads
(Bufo spp.) [36].
Hellebrin, shown in Figure 1, is the most familiar
cardioactive glycoside of Helleborus, being isolated and
quantied in roots and rhizomes of H. purpurascens
[37]. The structure of hellebrin was determined in 1995
by Muhr et al. using 2D NMR techniques [38]. Its ratio
was monitored in the whole plant, compared to degluco-
hellebrin [34]. This fraction was calculated also in
cultivated H. odorus and H. viridis over the annual cycle,
and the results showed that concentration of hellebrin
is higher in H. purpurascens compared to other species
[34].
4.2 Steroidal saponins
Saponins are steroid or triterpene glycosides widely
distributed in the plant and marine animal kingdoms
and include a large number of biologically active
compounds. In 1976, a medicine proposed to treat
ulcers and containing the main sapogenins from roots
and rhizomes of Helleborus spp. was registered under a
U.S. patent (O.I. Bruchköbel, 1976, Medicine containing
the main sapogenin from Helleborus, U.S. Patent
3,956,491). This class of natural compounds has a wide
structural diversity which may explain their multiple
ranges of bioactivity reported so far [39]. Some of the
steroidal saponins have cancer-related activity, as well
as immunomodulating, antihepatotoxic, antiviral, and
antifungal activities. Saponins have important action
Figure 1. Hellebrin.
O
O
O H
O H
O
O
O
O
O H
H O
O
O H
O H
HO
HO
Figure 2. Saponins skeletons found in Helleborus sp.
O
F u ro st an
O
O
S p ir o s ta n
274
M.C. Maior, C. Dobrotă
on the cardiovascular, central nervous and endocrine
systems [40-42]. Saponins reported in Helleborus spp.
have furostan and spirostan skeleton structures, shown
in Figure 2.
4.3 Ecdysones
Ecdysones are plant derived sterols, classed
as triterpenoids, with a very polar structure [35].
Phytoecdysteroids have been reported to occur in
over 100 terrestrial plant families representing ferns,
gymnosperms and angiosperms [43]. Ecdysteroids
can be found also in insect and crustacean families
and play a defensive role against predators or are
involved in plant metabolism [26,43]. Plant cells
synthesize phytoecdysteroids from mevalonic acid
in the mevalonate pathway, using acetyl-CoA as a
precursor. The largest concentration of ecdysteroids
was found in tissues involved in the defense mechanism
of the plants. Ecdysteroids are used by plants as a
protective mechanism against phytophagous insects.
Phytoecdysteroids can mimic the activity of moulting
hormones in insects and can disrupt moulting, perturbing
normal insect development [44]. When ingested by
non-adapted insects they lead to weight loss, moulting
disruption and/or mortality [45].
Some of the pharmacological effects of
phytoecdysteroids are summarized below: adaptogenic
and antidepresive, hepatoprotective (related to
phospholipid metabolism), chemopreventive (in
cancer treatment), effective in the control of diabetes,
and antimicrobial effects against some fungi and
bacteria species [43]. A well-known ecdysteroid,
20-hydroxyecdysone, found frequently in Helleborus
spp. is shown in Figure 3.
4.4 Protoanemonin
Protoanemonin (Figure 4) is a toxic γ-lactone of
hydroxy-penta-2,4-dienic acid [13]. Frohne and
Pfander described protoanemonin as a volatile, oily
and irritant substance with high afnity for SH groups
[31]. Protoanemonin is considered a biologically active
compound having antimicrobial [46,47], fungicidal
[48], and antimutagenic effects [49,50]. However,
Dickens reported brosarcoma development when
2 mg protoanemonin was injected repeatedly in rats
[51]. When drying the plant, protoanemonin comes
into contact with air and dimerizes to anemonin, a
non-stable compound which is hydrolyzed to a non-
toxic carboxylic acid [52]. Anemonin is also fungicidal
(less potent than protoanemonin) [48] and both of them
(anemonin and protoanemonin) have a sedative effect
[53]. Anemonin has also antispasmodic properties
[54]. Anemonin inhibits cellular tyrosinase activity and
affects protein and mRNA levels in human melanocytes
inhibiting melanin synthesis. That is why, anemonin
may be used as a cosmetic agent for hypopigmentary
purposes [55]. Anemonin is able to inhibit nitric oxide
(NO) production by modulating the expression of iNOS
(inducible nitric oxide synthase) [56,57]. This could
explain its anti-inammatory effects [57,58]. It was also
reported that anemonin inhibits endothelin-1 (ET-1)
[56,57] and intercellular adhesion molecule-1 (ICAM-1)
in RIMEC (rat intestinal microvascular endothelial cells)
preventing intestinal microvascular dysfunction [57]. It
was suggested that anemonin can be used for treating
various other diseases, including cardiovascular
diseases and arthritis when ET-1 and NO activation are
involved in mediation of pathogenesis [57].
Figure 4. Degradation pathway of protoanemonin.
O
O
H
2
C
P ro to a n em o n in
OO
O
O
C H
2
H
2
C
H
H
H
H
A ne m o nin
O H
H O
D im e r iz at io n
H y dr o ly si s
O
O
O
O
Figure 3. 20-Hydroxyecdysone
O H
O H
O H
O H
O
HO
H O
H
H
275
Natural compounds with important medical
potential found in
Helleborus
sp.
4.5 Current chemical analysis on Helleborus sp.
Over the past few years, different Helleborus species
have become the subject of phytochemical studies due to
their putative potential in producing valuable secondary
metabolites and due to the development of analytical
methods that offered the opportunity to perform faster
biochemical characterization of plant extracts. In order
to decipher their biochemical content, different chemical
analysis techniques were used: chemical transformations;
analytical methods (chromatography): TLC (Thin Layer
Chromatography), HPLC-MS (High Performance
Liquid Chromatography - Mass Spectrometry), RP-
HPLC (Reverse Phase - High Performance Liquid
Chromatography) GC (Gas Chromatography) and
various spectroscopic methods using 1D and 2D NMR
techniques: COSY (Correlated SpectroscopY), TOCSY
(Total Correlation SpectroscopY), ROESY (Rotating
frame nuclear Overhauser Effect SpectroscopY),
HMQC (Heteronuclear Multiple Quantum Correlation),
HMBC (Heteronuclear Multiple Bond Correlation). New
chemical compounds were identied and described
in Helleborus spp. and many of them seem to have
pharmacological activity and promising potential for
medical research. Chemical analysis advances on
Helleborus spp. through the last years are shown in
Table 1.
Species Tissue source Compounds Reference
H. odorus ssp. laxus,
H. viridis ssp. viridis
Roots and
rhizomes
hellebrin, degluco-hellebrin, hellebrigenin, bufatetraenolide, spirostane-
type steroids, β-ecdysterone, 5β-hydroxyecdysterone [59]
H. purpurascens Roots 1 new steroidal saponin, hellebrin,
β-ecdysterone, 5α-hydroxyecdysterone [60]
H. torquatus Seeds 3 new bufadienolides, 2 new ecdysteroids [61]
H. atrorubens Leaves 8 avonoids, 7 phenolic acids [62]
H. orientalis Rhizomes 1 novel polyoxygenated spirostanol glycoside [63]
H. orientalis Rhizomes 1 new bufadienolide rhamnoside, 2 bufadienolide glycosides, 5 new
spirostanol saponins [64]c
H. orientalis Rhizomes 2 new bisdesmosidic furostanol saponins,
2 new furospirostanol saponins [65]c
H. orientalis Rhizomes 2 new polyoxygenated spirostanol bisdesmosides, 1 new
polyoxygenated spirostanol trisdesmoside [66]c
H. viridis Leaves 2 new furostanol saponins, 3 new quercetin glycosides [67]
H. orientalis Roots a furostanol saponin, a phytoecdysteroid [68]
H. foetidus Leaves 1 new caffeoylated quercetin glycoside, 1 steroidal saponin, anemonin,
2 phenol glycosides [69]
H. caucasicus Roots and
rhizomes 2 sapogenins [70]
H. caucasicus Roots and
rhizomes
4 new polyhydroxylated and polyunsaturated furostanol glycosides
(caucasicosides) [71]
H. caucasicus Leaves 20-hydroxyecdysone, 1 spirostan [72]
H. bocconei ssp.
intermedius Roots 2 new furostanol saponins, 1 furospirostanol saponin, ecdysterone,
5β-hydroxyecdysterone [73]c
H. orientalis Rhizomes 8 new furostanol glycosides, 2 known furostanol glycosides [74]c
H. thibetanus Rhizomes 2 new bufadienolides, 2 bufadienolides [75]c
H. thibetanus Rhizomes 2 new bufadienolide glycosides, 2 ecdysteroids, 6 bufadienolide [76]
H. viridis Leaves 3 new steroidal saponins [77]
H. caucasicus Leaves 9 new furostanol glycosides, 9 furostanol glycosides, 1 bufadienolide,
1 ecdysteroid [78]
H. niger Leaves 1 new phenyllactic acid, 1 new avonol glycoside, 1 kaempferol
glycoside [79]
Table 1. Progress made over the last years on chemical analysis of Helleborus sp. c Authors that tested the compounds described in their papers
for cytotoxicity.
276
M.C. Maior, C. Dobrotă
4.6 Hellethionins
A new family of thionins was discovered in the roots of
H. purpurascens and named hellethionins. Hellethionins
are part of group of α/β thionins, small-sized multiple-
cystine peptides, that were found in endosperms
of grains, in seeds and in parasitic plants [80,81].
These are considered to be excellent candidates as
biocontrol agents of plant pathogens [82]. In vitro
experimental studies suggest that thionins are toxic to
bacteria, fungi, and yeasts due to their interaction with
membrane phospholipids and their capacity to form
ion channels. Possible roles in the defense of plants
against pathogens, directly at the membrane level,
are assumed. Also, hellethionins are thought to have a
function in cell death [83]. All thionins have the property
to refold correctly into the native structure, making them
robust scaffolds that can be exploited for screening of
optimized membrane activities and of cytotoxicity [81].
5. Pharmacological and therapeutic
effects
Studies concerning the pharmacological and therapeutic
effects of whole or partial Helleborus spp. extract have
been conducted in various animal models and in vitro
systems.
5.1 Antirheumatic and anti-inammatory
activity
Kerek presented for the rst time the benecial action
of a drug named Boicil [84], which was made from
H. purpurascens root and stem extract (V. Boici, 1977,
Analgesic substance derived from the Helleborus plant
and method of making same, U.S. Patent 4,012,505)
and has been successfully used in Romania for decades
to treat rheumatic pains. H. purpurascens extracts
exhibited high biological activity with lasting analgesic,
myorelaxant, and blood vessel regulating actions.
H. orientalis was tested in mice, using a carrageenan-
induced hind paw edema model, to determine anti-
inammatory activity and a p-benzoquinone-induced
abdominal constriction test, to determine antinociceptive
activity. The authors reported that a dose of 500 mg/kg
ethanolic extract of roots of H. orientalis showed anti-
inammatory activity without inducing any gastric
damage. Root and herb extracts, both alcoholic and
aqueous, were reported as antinociceptive, when a
dose of 500 mg/kg was tested [85].
5.2 Immunomodulatory activity
Many studies made on animals have demonstrated the
immunostimulatory effect of Helleborus spp. extracts.
Immunostimulatory effect of H. purpurascens was
reported in sheep. Increased number of lymphocytes
(2×) and neutrophiles (3.5×) after 48 h of injecting young
sheep with 5% decoct of radix and rhizome showed an
improved immune response of the animals [86]. Activation
of rapid, non-specic defensive mechanisms and poor
haemolysis has been reported when subcutaneous,
intraperitoneal and intramuscular application of different
concentrations of the extract of rhizome and root of
H. odorus were performed. A pronounced leukocytosis
and an increased percentage of neutrophil granulocytes
have been recorded [87]. These results were conrmed
by other authors supporting the idea that Helleborus
extracts can trigger unspecic immune response in
animals [20].
A feature related to immunomodulation was
assigned to chemical compounds found in Helleborus
spp. MCS-18 (macrocyclic carbon suboxide), a
multi-anionic compound extracted and puried from
H. purpurascens roots, classied as New Chemical Entity
(NCE) and originated in plants [88], was characterized
as a highly potent inhibitor of Na, K-ATPase and of the
SR Ca-ATPase [89,90].
MCS-18 has a complex structure and in the last
years has been intensively studied. It induces in vitro
up-regulation of the immune modulatory cytokines IL-10
and TGF-β [91]. Also, MCS-18 efciently downregulates
T-cell-dependent antibody (Ab) formation in mice, where
a Toll-like-receptor (TLR) blockade might be involved.
MCS-18 leads to a strong attenuation of antibodies
against tetanus toxoid if administered together with
the Ab elicitor Freund’s Complete or TLR antagonists
in various combinations. These ndings suggest that
MCS-18 could be a potent, non-toxic antagonist or
a down-regulator of the TLR signaling pathway [92].
MCS-18 proved to be a potent antagonist of the capsaicin
activated vanilloid type pain receptors (TRPV1) and
explains its local analgesic action [93].
To MCS-18 was assigned an important role in
autoimmunity. MCS-18 strongly reduced the paralysis
associated with the experimental autoimmune
encephalomyelitis (EAE), which is a murine model
for human multiple sclerosis. This compound can be
used in the EAE model not only as a prophylactic, but
also as a therapeutic setting. It was also proved that
MCS-18 induces a long-lasting suppressive effect and
is able to inhibit the expression of typical molecules of
mature dendritic cells (DC). This compound impeded
the formation of the typical DC/T-cell clusters, which
are essential to induce potent immune responses [94].
Another paper that supported the above mentioned facts,
added that MCS-18 also reduced B-cell proliferation and
immunoglobulin production [95].
277
Natural compounds with important medical
potential found in
Helleborus
sp.
MCS-18 treatment almost completely reduced
leukocyte inltration in the brain and in the spinal
cord. Using EAE assay in vitro as well in vivo the
authors were able to show that MCS-18 exerts a
strong immunosuppressive activity with remarkable
potential for the therapy of diseases characterized by
a pathologically over-activated immune system. They
concluded that MCS-18 is an efcient modulator of
immune response in vitro and in vivo and that is able
to inhibit the disease symptoms at different stages [94].
The authors demonstrated that MCS-18 has a very
potent non-toxic immune-suppressive activity and their
results were strongly supported by clinical trial data
reporting that MCS-18 is a highly effective drug in the
treatment of arthritis.
Type I diabetes is still a serious problem for which
the medical community is looking for new ways to
prevent and overcome. MCS-18 could become a
promising answer for people suffering diabetes.
NOD-mouse model was used to observe the MCS-18
treatment, indicating signicantly reduced islet T-cell
inltrates and the rate of T-cell proliferation. Periinsular
inltrates in the MCS-18 treated animals showed a
signicantly enhanced number of Foxp3(+) CD25(+) T
cells, indicating the increased presence of regulatory T
cells. In the animal group which had been treated with
MCS-18, 70% of the animals showed a diabetes free
survival, in comparison with untreated animals where
only less than 10% were free of diabetes. These
studies showed that MCS-18 exerts an efcient
immunosuppressive activity with remarkable potential
for the therapy of diseases characterized by pathological
over-activation of the immune system [96].
5.3 Antioxidant activity
ROS (reactive oxygen species) are products of cellular
metabolism having important functions in cell signaling,
homeostasis and apoptosis, activation of host defense
genes and mobilization of ion transport systems. ROS
have an important role in immune system functioning.
Five progressively puried MCS-products from
H. purpurascens were tested as possible antioxidants
and/or modulators of ROS production and released
from human polymorphonuclear granulocytes cells.
One of the fractions MCS-Dx proved to be a potent ROS
scavenger and it could be used as adjuvant in antioxidant
therapy [97]. Even a simple aqueous or hydroalcoholic
extract, concentrated by ultraltration, proved to have
high antioxidant activity. The DPPH (2,2-diphenyl-
1-picrylhydrazyl) inhibition value of hydroalcoholic
extract showed the highest antioxidant activity (79%),
while the concentrated aqueous extract showed 73%
DPPH inhibition [98]. Čakar et al. measured antioxidant
activity in root and leaf extracts from H. odorus,
H. multidus and H. hercegovinus leaf extract exhibiting
a higher antioxidant activity (IC50 values between
0.12-0.89 mg/ml) compared to root extract (IC50 values
between 0.72-3.10 mg/ml) [99]. Another compound
found in Helleborus spp. that proved to be antioxidant
is 20-hydroxyecdysone, an ecdysteroid that acts
as a uoride-stimulated respiratory burst modulator
in the same manner as water soluble antioxidants,
chlorpromazine and emoxipin [100]. This compound,
alone or acting in synergy, could render the antioxidant
activity assigned to these plants.
5.4 Antimicrobial activity
Although many Helleborus spp. have been used to treat
infectious diseases in animals, the antimicrobial activity
of these species was not screened. There are just a few
studies concerning this aspect [101,102]. Roots from H.
bocconei ssp. siculus were tested for their antibacterial
activity against microorganisms responsible for
respiratory infections. Seven strains of microorganisms
responsible for these types of infections were tested:
Staphylococcus aureus ATCC 29213, Streptococcus
pneumoniae ATCC 49619, Escherichia coli ATCC
25922, Haemophilus inuenzae ATCC 49247, Moraxella
catarrhalis ATCC 25238, Pseudomonas aeruginosa
ATCC 27853, and Stenotrophomonas maltophilia ATCC
13637. The root methanolic extract and its bufadienolide
fraction showed the lowest Minimum Inhibitory
Concentration values (100 μg/ml) against Moraxella
catarrhalis (0.2, 0.1) and Streptococcus pneumonia
(0.4, 0.1) [101].
5.5 Cytotoxicity and anticancer properties
Many species of Helleborus are seen today as potential
sources for anticancer drugs. Studies involving extracts
or chemical compounds gave optimistic results related
to cancer inhibition and cytotoxicity. Lindholm et al.
[103] tested, through a large-scale screening protocol,
100 fractionated plant extracts, seven of them showing
interesting cytotoxic properties. The cytotoxic activity
was not fully characterized, but H. cyclophyllus extract
proved to have antitumoral potential. Another species,
H. caucasicus, also showed cytotoxic activity. Root and
rhizome alcoholic extracts were tested against human
lung cancer (A-549), human colorectal cancer (DLD-1)
and normal skin broblasts (WS1) and their cytotoxic
dose was reported as being rather low (0.002 μg/ml)
[104].
H. niger extracts were used for in vitro tests
involving hematological malignancies. Inhibition of cell
proliferation is caused by specic apoptosis induction
via mitochondrial pathway and caspase-3 processing.
278
M.C. Maior, C. Dobrotă
Apoptosis induction was observed in lymphoma (BJAB),
leukemia (REH, Nalm6, Sup-B15) and melanoma
(Mel-HO) cells. A better efciency in inducing apoptosis
was recorded when whole plant and root extracts were
used compared to leaf and blossom extracts. When
a concentration of 0.75 mg/ml H. niger extract was
added to a BJAB cell line, an inhibition up to 96.5% of
the proliferation rate was recorded. Synergistic effects
were also observed when a cytostatic drug - vincristine
- was added to the BJAB cell culture in combination with
H. niger whole plant extract.
Although apoptosis in Mel-OH cell line was correlated
with Bcl-2 protein overexpression, sensitivity to H. niger
extract was clearly recorded [105]. Another extract from
roots of H. bocconei ssp. intermedius proved to have
cytotoxic activity against rat C6 glioma cells. Three
isolated compounds, a hydrolyzed form of helleboroside
B, a furospirostanol saponin and polypodyne B showed
signicant cytotoxic activity, recording a 60-70%
inhibition of the cell growth [73].
In a similar comparative study, root extracts from
H. odorus, H. multidus and H. hercegovinus proved to
be more efcient than leaves extract of the same species
on inhibiting growth of BJAB cell lines. The strongest
antiproliferative activity was indicated for root extracts of
H. multidus and H. hercegovinus which inhibited BJAB
cell lines growth with 50.14% and 49.04%, respectively
[99]. Hellebosaponin C, a spirostanol glycoside,
and another two furostanol glycosides isolated from
rhizomes of H. orientalis exhibited a moderate cytotoxic
activity against human oral squamous cell carcinoma
(HSC-2) [66,74].
Two new bufadienolides (tigencaoside A, B) found in
rhizomes of H. thibetanus were also tested for cytotoxic
activity against human cancer cells 3LL, MCF-7, QGY-
7701 and BGC-823. The IC50 values of tigencaoside A
on the tested cell lines ranged between 105.23–253.12
μg/ml and for tigencaoside B exhibited values were
between 56.54–86.45 μg/ml [75].
Potential cytostatic and cytotoxic effects of
H.purpurascens hydrous extract (HphE) and
H. purpurascens hydroalchoholic extract (HphaE) were
recently evaluated by Vochita et al. [106]. Total and
fractionated polyphenolic compounds were extracted
from roots and rhizomes of H. purpurascens and tested
on HeLa cancerous cells. Tested biopreparations as
0.45 µm MF-HphE (microltrate of HphE), 30,000 Da
UF1P-HphE (permeate of rst ultraltrate), 10,000 Da
UF2C-HphE (concentrate of second ultraltrate),
10,000 Da UF2P-HphE (permeate of second ultraltrate)
exert a very strong cytostatic effect with values over
90%. Other biopreparations as HphE (total hydrous
extract), 30,000 Da UF1P-HphE, 3,000 Da UF3C-HphE
(concentrate of third ultraltrate), 3,000 Da UF3P-HphE
(permeate of third ultraltrate) induce an inhibition of the
tumor cell between 59.46% and 67.80%.
Thionins - the class of peptide that was found also
in H. purpurascens - have been proposed as potential
immunotoxins in tumor therapy. Cytotoxicity of thionins
has led to the development of a potential application:
targeting thionins by tumor-specic antibodies, which is
expected to support antitumor therapy [81]. Anticancer
properties of hellethionins were reported by Kerek.
Acting alone or synergistic, hellethionins proved
to inhibit proliferation in different cancer cell lines.
Hellethionin C, at very low concentration (2 µg/ml),
causes a clear inhibition of proliferation in MFC-7 cell
line (breast cancer cell culture). Hellethionin C and
hellethionin D, at a concentration of 100 µg/ml, strongly
inhibit (48.36% and 58.66%, respectively) the culture of
Colo 205 (colon cancer cell line). Hellethionin C at 50 µg/ml
in combination with MCS-18 at 100 µg/ml inhibits the
growth of Colo 205 with 66%. A mixture of hellethionins
B (B1: B2: B3 = 1:1:1), hellethionin C and hellethionin D
at a concentration of 100 µg/ml were also able to inhibit
with 50% the growth of a lung carcinoma cell line (Kerek
F., 2010, Petides having a high cysteine content, U.S.
Patent 7,750,114 B2).
Another recently registered patent is describing
methods for obtaining new cardiac steroids starting
from hellebrin and hellebrigenin and using conventional
techniques of synthetic organic chemistry (J. Dewelle, M.
El Yazidi, E. Van Quaquebeke, N. De Neve, T. Mijatovic,
L. Ingrassia, et al., 2010, Hellebrin and hellebrigenin
derivatives, WO2010/102673). Apparently, the 21 novel
hellebrin and hellebrigenin derivatives have a cytotoxic
activity with reduced general toxicity. These compounds
were tested against six human cancer cell lines in
the MTT tests, and a number of these compounds
showed very potent in vitro antitumor activity with IC50
values in the nanomolar range. That was why these
compounds were proposed as medicines for cancer
treatment. The authors also used two normal broblast
cell lines to investigate potential compound selectivity
towards cancer. Almost all described compounds
displayed in vitro marked selectivity toward cancer cells
(J. Dewelle, M. El Yazidi, E. Van Quaquebeke, N. De
Neve, T. Mijatovic, L. Ingrassia, et al., 2010, Hellebrin
and hellebrigenin derivatives, WO2010/102673). We
may consider that Helleborus spp., having so many
valuable chemical compounds, are potential pools for
a wide range of pharmacological agents and bioactive
molecules.
H. niger aqueous extracts were tested in order
to asses a DNA destabilizing risk. Sister Chromatid
Exchange assay (SCE) was used to detect DNA
279
Natural compounds with important medical
potential found in
Helleborus
sp.
damage. The authors found that H. niger aqueous
extract possesses immunomodulating properties
and also exerts slight effects of DNA destabilization
and might have a mutagenic effect on human PBMC
(peripheral blood mononuclear cells) [107].
6. Micropropagation and genetic
transformation
Harvesting wild medicinal plants is often nonproductive.
In the case of plants such as Helleborus, where the
targeted medicine is located in roots and the seeds have
a low germination rate, sustainable propagation could
be a better option. The latest considerable discoveries
concerning hellebores have used in vitro cultivation as
an easier way to study them and for nding new methods
to use their features. In vitro techniques consisting of
micropropagation, callus culture, cell suspension culture
or somaclonal variation, could improve the production of
secondary metabolites. Smulders and de Klerk reported
that 4 different lines of Helleborus spp., having the same
source, remained unmodied during many subcultures,
a feature which may be used in producing new
varieties and in synthesizing new chemical compounds
[108]. The antimicrobial activity of hellethionins could
be used in genetic engineering. Transgenic plants
containing thionin genes can enhance resistance
against pathogens. Hellethionins are peptides that are
promising candidates for engineered plant resistance
in the agricultural industry (81, Y. Ohashi, I. Mitsuhara,
M. Oshshima, M. Ugaki, H. Hirochika, R. Honkura,
et al., 1998, Method for producing disease resistant
plant with thionin gene from Avena sativa, U.S. Patent
6, 187, 995).
After the isolation and identication of these new
important chemicals, the next step in using this potential
would be molecular farming. Genetically engineered
plants with new traits could have extra resistance to
insect attack and improved weed control, or could
produce a large quantity of pharmaceutically active
compounds.
Computer- based analysis revealed that natural
products exhibit a remarkable structural diversity of
molecular frameworks and scaffolds that could be
systematically exploited for combinatorial synthesis.
Natural products offer a rich pool of unique molecular
frameworks and desirable drug-like properties,
rendering them ideal starting points for molecular design
considerations [109].
7. Conclusions and perspectives
Important progress on isolation and identication
of bioactive compounds from Helleborus species
has been made in the past few years. However,
further studies concerning the assessment of their
pharmacological and therapeutic effects and clinical
trials concerning the target-organ toxicity or side
effects, are still required.
There are many studies which strongly support
the view that extracts of the plants belonging to this
genus have benecial therapeutic actions. It is known
that the active principles are effective remedies in anti-
inamatory and antirheumatic conditions, and have
proven efciency as immunostimulators, antioxidants,
antimicrobial and antitumoral agents.
Even if there are some patents concerning active
compounds, Helleborus species are still insufficiently
explored as a source of valuable products and that
further studies need to be done. Precise clinical
trials using a large number of patients have to be
encouraged in order to evidence the efficacious and
possible side effects of the newly found compounds.
New research approaches on this topic may concern
the assessment of the effects of novel compounds
discovered, the mechanisms of their action, the
interplay with known regulatory components at the
protein level to provide an understanding of their
dynamic interactions and how these interactions
orchestrate the biosynthesis of secondary
metabolites in plants. Achieving these goals will
translate into a major advance in our understanding
of how plant bioactive compounds actually work,
since our understantding of interactions at the
cellular level is limited. This will not only generate
fundamental knowledge about the dynamics of plant
biosynthesis, but will ultimately provide us with the
tools to rationally reprogram secondary metabolism
for genetically engineering more useful plants.
Acknowledgements
This work was possible with the nancial support of the
Sectoral Operational Programme for Human Resources
Development 2007-2013, co-nanced by the European
Social Fund, under the project number POSDRU
89/1.5/S/60189 with the title „Postdoctoral Programs
for Sustainable Development in a Knowledge Based
Society”.
280
M.C. Maior, C. Dobrotă
[1] Toma C., Rugină R., Medicinal plant’s anatomy.
Atlas, [Anatomia plantelor medicinale. Atlas],
Romanian Academy Ed., Bucharest, 1998 (in
Romanian)
[2] Kemertelidze E.P., Biologically active compounds
and original remedies from plants growing in
Georgia, Bull. Georgian Natl. Acad. Sci., 2007,
175, 91-96
[3] van Tellingen C., Pliny’s pharmacopoeia or the
Roman treatment, Neth. Heart J., 2007, 15, 118-
120
[4] Brussel D.E., Medicinal plants of Mt. Pelion,
Greece, Econ. Bot., 2004, 58, S174-S202
[5] Ramoutsaki I.A., Askitopoulou H., Konsolaki E.,
Pain relief and sedation in Roman Byzantine texts:
Mandragoras ofcinarum, Hyoscyamos niger and
Atropa belladonna, International Congress Series,
2002, 1242, 43–50
[6] Ciulei I., Grigorescu E., Stănescu U., Medicinal
plants, phytochemistry and phytotherapy [Plante
medicinale, tochimie si toterapie, Vol. 1], Medical
Ed., Bucharest, 1993 (in Romanian)
[7] Adams M., Althera W., Kessler M., Kluge M.,
Hamburger M., Malaria in the renaissance:
Remedies from European herbals from the 16th
and 17th century, J. Ethnopharmacol., 2011, 133,
278–288
[8] Scherrer A.M., Motti R., Weckerle C.S., Traditional
plant use in the areas of Monte Vesole and Ascea,
Cilento National Park (Campania, Southern Italy),
J. Ethnopharmacol., 2005, 97, 129–143
[9] Fujita T., Sezik E., Tabata M., Yeşilada E., Honda
G., Takeda Y., et al., Traditional medicine in Turkey
VII. Folk medicine in Middle and West Black Sea
regions, Econ. Bot., 1995, 49, 406–422
[10] Menković N., Šavikin K., Tasić S., Zdunić G.,
Stešević D., Milosavljević S., et al., Ethnobotanical
study on traditional uses of wild medicinal
plants in Prokletije Mountains (Montenegro), J.
Ethnopharmacol., 2011, 133, 97–107
[11] Idolo M., Motti R., Mazzoleni S., Ethnobotanical
and phytomedicinal knowledge in a long-
history protected area, the Abruzzo, Lazio and
Molise National Park (Italian Apennines), J.
Ethnopharmacol., 2010, 127, 379–395
[12] Duke J.A., Bogenschutz-Godwin M.J., duCellier J.,
Duke P.-A.K., Handbook of Medicinal Herbs, 2nd
ed., CRC Press LLC, Boca Raton, Florida, 2002
[13] Adams M., Berset C., Kessler M., Hamburger M.,
Medicinal herbs for the treatment of rheumatic
disorders—A survey of European herbals from the
16th and 17th century, J. Ethnopharmacol., 2009,
121, 343-359
[14] Gomes N.G.M., Campos M.G., Órfão J.M.C.,
Ribeiro C.A.F., Plants with neurobiological activity
as potential targets for drug discovery, Prog.
Neuro-Psychopharmacol Biol Psychiatry, 2009, 33,
1372–1389
[15] Jäger A.K., Gauguin B., Adsersen A., Gudiksen L.,
Screening of plants used in Danish folk medicine to
treat epilepsy and convulsions, J. Ethnopharmacol.,
2006, 105, 294–300
[16] Cornara L., La Rocca A., Marsili S., Mariotti M.G.,
Traditional uses of plants in the Eastern Riviera
(Liguria, Italy), J. Ethnopharmacol., 2009, 125, 16-
30
[17] Passalacqua N.G., De Fine G., Guarrera P.M.,
Contribution to the knowledge of the veterinary
science and of the ethnobotany in Calabria region
(Southern Italy), J. Ethnobiol. Ethnomed., 2006, 2,
52
[18] Pieroni A., Nebel S., Quave C., Münz H., Heinrich
M., Ethnopharmacy of the ethnic Albanians
(Arbëreshë) of northern Basilicata, Italy. Fitoterapia,
2002, 73, 217-241
[19] Jarić S., Popović Z., Mačukanović-Jocić M.,
Djurdjević L., Mijatović M., Karadžić B., et al., An
ethnobotanical study on the usage of wild medicinal
herbs from Kopaonik Mountain (Central Serbia), J.
Ethnopharmacol., 2007, 111, 160–175
[20] Bogdan I., Nechifor A., Basea I., Hruban E., From
Romanian folk medicine: nonspecic stimulus
therapy using transcutaneous implantation
of hellebore (Helleborus purpurascens, Fam.
Ranunculaceae) in agriculturally useful animals,
Dtsch. Tieraerztl. Wochenschr., 1997, 97, 525-
529
[21] Pârvu C., Plant’s Universe. Small encyclopaedia
[Universul plantelor. Mica enciclopedie], 3rd ed.,
Encyclopaedia Ed., Bucharest, 2000 (in Romanian)
[22] Hussain A., Khan M.N., Iqbal Z., Sajid M.S., An
account of the botanical anthelmintics used in
traditional veterinary practices in Sahiwal district of
Punjab, Pakistan, J. Ethnopharmacol., 2008, 119,
185–190
[23] Pascual-Villalobos M.J., Robledo A., Screening for
antiinsect activity in Mediterranean plants, Indust.
Crops Prod., 1998, 8, 183–194
[24] Prieto J.M., Schaffner U., Barker A., Braca A.,
Siciliano T., Boevé J.-L., Sequestration of furostanol
saponins by Monophadnus sawy larvae, J. Chem.
Ecol., 2007, 33, 513–524
References
281
Natural compounds with important medical
potential found in
Helleborus
sp.
[25] Flomenbaum N.E., Goldfrank L.R., Hoffman R.S.,
Howland M.A, Lewin N.A., Nelson L.S., Goldfrank’s
Toxicologic Emergencies, 8th ed., McGraw Hill
Companies Inc., 2006
[26] Bruneton J., Pharmacognosy, Phytochemistry,
Medicinal plants [Pharmacognosie, Phytochimie,
Plantes medicinales], 4th ed., Tec & Doc Ed.,
Éditions médicales internationals, Paris, France,
2009 (in French)
[27] True B.L., Dreisbach R.H., Dreisbach’s Handbook
of Poisoning: Prevention, Diagnosis & Treatment,
13th ed., The Parthenon Publishing Group,
London, UK, 2002
[28] Cooper, M.R., Johnson A.W., Poisonous Plants
& Fungi: An Illustrated Guide Stationery Ofce
Books, Norwich, 1988
[29] Fuller T.C., McClintock E.M., Poisonous Plants of
California, University of California Press, Berkeley,
California, 1986
[30] Karaca S., Kulac M., Kucuker H., Phytodermatitis
caused by Ceratocephalus falcatus
(Ranunculaceae), Eur. J. Dermatol., 2005, 15, 404-
405
[31] Frohne, D., Pfander, H.J., Poisonous Plants: a
handbook for doctors, pharmacists toxicologists,
biologists and veterinarians, 2nd ed. Manson
Publishing Inc., London, 2005
[32] Karrer W., About hellebrin, a crystallized glycosid
from Helleborus nigri roots [Über Hellebrin, ein
kristalisiertes Glycosid aus Radix Hellebori nigri],
Helv. Chim. Acta, 1943, 26, 1353 (in German)
[33] Wissner W., Kating H., Botanical and phytochemical
investigations of species of the genus Helleborus
growing in Europe and Asian Minor. II. Comparative
phytochemical investigations of the cardio active
glycosides and saponins, Planta Med., 1974, 26,
228–249
[34] Wissner W., Kating H., Botanical and phytochemical
investigations of species of the genus Helleborus
growing in Europe and Asian Minor - III. The
quantitative contents of hellebrin in plants of the
natural biotops and in culture, Planta Med., 1974,
26, 364-374
[35] Dewick P.M., Medicinal Natural Products: A
Biosynthetic Approach, 2nd ed., John Wiley &
Sons Inc., New York, USA, 2002
[36] Gao H., Popescu R., Kopp B., Wang Z.,
Bufadienolides and their antitumor activity, Nat.
Prod. Rep., 2011, 28, 953-969
[37] Cioca C., Cucu V., Quantitative determination of
hellebrin in the rhizomes and roots of Helleborus
purpurascens W. et K., Planta Med., 1974, 26, 250-
253
[38] Muhr P., Kerek F., Dreveny D., Likussar W.,
Schubert-Zsilavecz M., The structure of hellebrin,
Liebigs Ann., 1995, 2, 443-444
[39] Challinor V.L., Piacente S., De Voss J.J., NMR
assignment of the absolute conguration of C-25 in
furostanol steroidal saponins, Steroids, 2012, 77,
504-511
[40] Lacaille-Dubois M.A., Wagner H., A review of
the biological and pharmacological activities of
saponins, Phytomedicine, 1996, 2, 363-386
[41] Lacaille-Dubois M.A., Wagner H., Bioactive
saponins from plants: An update, In: Atta-ur-
Rahman (Ed.), Studies in Natural Products
Chemistry, Vol. 21, Elsevier, 2000
[42] Lacaille-Dubois M.A., Bioactive saponins with
cancer related and immunomodulatory activity:
Recent developments, In: Atta-ur-Rahman (Ed.),
Studies in Natural Products Chemistry, Vol. 32,
Elsevier, 2005
[43] Dinan L., Phytoecdysteroids: biological aspects,
Phytochemistry, 2001, 57, 325-339
[44] Walters D., Plant Defense: Warding off attack by
pathogens, herbivores and parasitic plants, 1st ed.,
Blackwell Publishing Ltd., 2011
[45] Klein R., Phytoecdysteroids, Journal of American
Herbalists Guild, 2004, 18-28
[46] Mares D., Antimicrobial activity of protoanemonin,
a lactone from ranunculaceous plant.
Mycopathologia, 1987, 98, 133-140
[47] Tocan V., Baron O., Antibiotic effect of
protoanemonine isolated from Ranunculus
oxyspermus M.B., Boll. Chim. Farm., 1969,108,
789-791
[48] Misra S., Dixit S., Antifungal principle of Ranunculus
sceleratus, Econ. Bot. 1980, 34, 362-367
[49] Minakata H., Komura H., Nakanishi K., Kada T.,
Protoanemonin, an antimutagen isolated from
plants, Mutation Research/Genetic Toxicology,
1983, 116, 317-322
[50] Martin M.L., San Roman L., Dominguez A., In vitro
activity of protoanemonin, an antifungal agent,
Planta Med., 1990, 56, 66-69
[51] Dickens F., Jones H.E.H., Carcinogenic activity of a
series of reactive lactones and related substances,
Br. J. Cancer, 1961, 15, 85–100
[52] Habermehl G.G., Ziemer P., Mitteleuropäische
Giftpanzen und ihre Wirkstoffe [Central European
poisonous plants and their active ingredients]
Springer, Berlin, 1999 (in German)
[53] Martin, M.L., Ortiz de Urbina A.V., Montero M.J.,
Carron R., San Roman L., Pharmacologic effects
of lactones isolated from Pulsatilla alpina subsp.
Aphfolia, J. Ethnopharmacol., 1988, 24, 185-191
282
M.C. Maior, C. Dobrotă
[54] Roth L., Daunderer M., Kormann K., Giftpanzen-
Panzengifte [Poisonous plants-phytotoxins] Nikol
Verlag, Hamburg, 2006 (in German)
[55] Huang, Y.-H., Lee T.-H., Chan K.-J., Hsu F.-L., Wu
Y.-C., Lee M.-H., Anemonin is a natural bioactive
compound that can regulate tyrosinase-related
proteins and mRNA in human melanocytes, J.
Dermatol. Sci., 2008, 49, 115-123
[56] Hu Y., Chen X., Duan H., Hu, Y.L., Mu X., Pulsatilla
decoction and its active ingredients inhibit secretion
of NO, ET-1, TNF-alpha, and IL-1 alpha in LPS-
induced rat intestinal microvascular endothelial
cells, Cell Biochem. Funct., 2009, 27, 284-288
[57] Duan H., Zhang Y., Xu J., Qiao J., Suo Z., Hu
G., Mu X., Effect of anemonin on NO, ET-1 and
ICAM-1 production in rat intestinal microvascular
endothelial cells, J. Ethnopharmacol., 2006, 104,
362-366
[58] Lee T.H., Huang N.K., Lai T.C., Yang A.T.Y., Wang
G.J., Anemonin, from Clematis crassifolia, potent
and selective inducible nitric oxide synthase
inhibitor, J. Ethnopharmacol., 2008, 116, 518-
527
[59] Colombo M.L., Tome’ F., Servettaz O., Bugatti C.,
Phytochemical evaluation of Helleborus species
growing in northern Italy, Pharm. Biol., 1990, 28,
219-223
[60] Dirsch V., Lacaille-Dubois M.-A., Wagner H.,
Dracoside, a new steroidal saponin from Helleborus
purpurascens, Nat. Prod. Lett., 1994, 4, 29-33
[61] Meng Y., Whiting P., Šik V., Rees H. H., Dinan L.,
Ecdysteroids and bufadienolides from Helleborus
torquatus (Ranunculaceae), Phytochemistry, 2001,
57, 401–407
[62] Maleš Z., Medić-Šarić M., Optimization of TLC
analysis of avonoids and phenolic acids of
Helleborus atrorubens Waldst. et Kit., J. Pharm.
Biomed. Anal., 2001, 24, 353-359
[63] Watanabe K., Mimaki Y., Sakuma C., Sashida Y.,
A novel polyoxygenated spirostanol trisdesmoside
from the rhizomes of Helleborus orientalis, Chem.
Lett., 2002, 31, 772–773
[64] Watanabe K., Mimaki Y., Sakagami H., Sashida
Y., Bufadienolide and spirostanol glycosides from
the rhizomes of Helleborus orientalis, J. Nat. Prod.,
2003, 66, 236–241
[65] Watanabe K., Sakagami H., Mimaki Y., Four new
steroidal saponins from the rhizomes of Helleborus
orientalis, Heterocycles, 2005, 65, 775–785
[66] Mimaki Y., Watanabe K., Sakuma C., Sakagami
H., Sashida Y., Novel polyoxygenated spirostanol
glycosides from the rhizomes of Helleborus
orientalis, Helv. Chim. Acta, 2003, 86, 398-407
[67] Braca A., Prieto J.M., De Tommasi N., Tomè F.,
Morelli I., Furostanol saponins and quercetin
glycosides from the leaves of Helleborus viridis L.,
Phytochemistry, 2004, 65, 2921-2928
[68] Akin S., Anil H., A furostanol saponin and
phytoecdysteroid from roots of Helleborus
orientalis, Chem. Nat. Compd., 2007, 43, 90-92
[69] Prieto J.M., Siciliano T., Braca A., A new acylated
quercetin glycoside and other secondary
metabolites from Helleborus foetidus, Fitoterapia,
2006, 77, 203–207
[70] Muzashvili T.S., Benidze M.M., Skhirtladze A.V.,
Sulakvelidze Ts. P., Steroidal sapogenins from
subterranean organs of Helleborus caucasicus,
Chem. Nat. Compd., 2006, 42, 613
[71] Bassarello C., Muzashvili T., Skhirtladze A.,
Kemertelidze E., Pizza C., Piacente S., Steroidal
glycosides from the underground parts of
Helleborus caucasicus, Phytochemistry, 2008, 69,
1227–1233
[72] Muzashvili T.S., Kemertelidze E.P., Steroidal
compounds from Helleborus caucasicus leaves,
Chem. Nat. Compd., 2009, 45, 925-926
[73] Rosselli S., Maggio A., Bruno M., Spadaro V.,
Formisano C., Irace C., et al., Furostanol saponins
and ecdysones with cytotoxic activity from
Helleborus bocconei ssp. intermedius, Phytother.
Res., 2009, 23, 1243–1249
[74] Mimaki Y., Matsuo Y., Watanabe K., Sakagami H.,
Furostanol glycosides from the rhizomes of Helleborus
orientalis, J. Nat. Med., 2010, 64, 452–459
[75] Yang J., Zhang Y.-H., Miao F., Zhou L., Sun W.,
Two new bufadienolides from the rhizomes of
Helleborus thibetanus Franch, Fitoterapia, 2010,
81, 636–639
[76] Yang F.-Y., Su Y.-F., Wang Y., Chai X., Han X., Wu
Z.-H., et al., Bufadienolides and phytoecdysones
from the rhizomes of Helleborus thibetanus
(Ranunculaceae), Biochem. Sys. Ecol., 2010, 38,
759–763
[77] Stochmal A., Perrone A., Piacente S., Oleszek W.,
Saponins in aerial parts of Helleborus viridis L.,
Phytochem. Lett., 2010, 3, 129–132
[78] Muzashvili T., Perrone A., Napolitano A.,
Kemertelidze E., Pizza C., Piacente S.,
Caucasicosides E–M, furostanol glycosides from
Helleborus caucasicus, Phytochemistry, 2011, 72,
2180–2188
[79] Vitalini S., Braca A., Fico G., Study on secondary
metabolite content of Helleborus niger L. leaves,
Fitoterapia, 2011, 82, 152-154
[80] Stec B., Plant thionins – the structural perspective,
Cell. Mol. Life Sci., 2006, 63, 1370-1385
283
Natural compounds with important medical
potential found in
Helleborus
sp.
[81] Milbradt A.G., Kerek F., Moroder L., Renner C.,
Structural Characterization of Hellethionins from
Helleborus purpurascens, Biochemistry, 2003,
42, 2404-2411
[82] Bhave M., Methuku D.R., Small cysteine-
rich proteins from plants: a rich resource of
antimicrobial agents, In: Science against
microbial pathogens: communicating current
research and technological advances, Ed. A.
Méndez-Vilas, 2011, 1074-1083
[83] Pelegrini P.B., Franco O.L., Plant γ-thionnins:
Novel insights of the mechanism of action of the
multi-functional class of defence proteins, Int. J.
Biochem. Cell B., 2005, 37, 2239-2253
[84] Kerek F., Boicil, a new and very efcient antialgic,
spasmolytic, and blood vessel regulating
drug obtained from the plant Helleborus. First
International Conference on Chemistry and
Biochemistry of Biologically Active Natural
Compounds (FECS, 1981), 2, 22–37
[85] Erdemoglu N., Küpeli E., Yeşilada E., Anti-
inammatory and antinociceptive activity
assessment of plants used as remedy in Turkish
folk medicine, J. Ethnopharmacol., 2003, 89,
123–129
[86] Nueleanu V.I., The effect of the unspecic therapy
with hellebore (Helleborus purpurascens) on
young sheep, Proceedings. Animal Husbandry.
43rd Croatian and 3rd International Symposium
on Agriculture, (18-21 February 2008, Opatija,
Croatia), 791-794
[87] Davidović V., Joksimović Todorović M., Stojanović
B., Relić, R., Plant usage in protecting the
farm animal health, Biotechnology in Animal
Husbandry, 2012, 28, 87-98
[88] Lupu A.R., MCS-18 – potential therapeutic agent
in neuro-immunological pathology [MCS-18
- potential agent terapeutic in patologii neuro-
imune], Ph.D. Thesis, University of Bucharest,
Faculty of Biology, Bucharest, Romania, 2009
(in Romanian)
[89] Kerek F., Stimac R., Apell H.-J., Freudenmann F.,
Moroder L., Characterization of the macrocyclic
carbon suboxide factors as potent Na, K-ATPase
and SR Ca-ATPase inhibitors, Biochim. Biophys.
Acta, 2002, 1567, 213-220
[90] Kerek F., The structure of the digitalis like and
natriuretic factors identied as macrocyclic
derivatives of the inorganic carbon suboxide,
Hypertens. Res., 2000, 23, 33-38
[91] Szegli G., Herold A., Cremer L., Călugaru
A., Matache C., Durbaca S., et al.,
Immunpharmacology studies on MCS-18,
Investigational Medicinal Product Dossier, 2005,
Part 2.2, 1–42
[92] Kerek F., Szegli G., Cremer L., Lupu A.R.,
Durbaca S., Călugaru A., et al., The novel arthritis
drug-substance MCS-18 down-regulates in vivo
antibody production, Acta Microbiol. Immunol.
Hung., 2008, 55, 15-31
[93] Neacşu C., Ciobanu C., Barbu I., Toader O.,
Szegli G., Kerek F., et al., Substance MCS-
18 isolated from Helleborus purpurascens is
a potent antagonist of the capsaicin receptor,
TRPV1, in rat cultured sensory neurons, Physiol.
Res., 2010, 59, 289-298
[94] Horstmann B., Zinser E., Turza N., Kerek
F., Steinkasserer A., MCS-18, a novel
natural product isolated from Helleborus
purpurascens, inhibits dendritic cell activation
and prevents autoimmunity as shown in vivo
using the EAE model, Immunobiology, 2008,
212, 839–853
[95] Littmann L., Röβner S., Kerek F., Steinkasserer
A., Zinser E., Modulation of murine bone marrow-
derived dendritic cells and B-cells by MCS-
18 a natural product isolated from Helleborus
purpurascens, Immunobiology, 2008, 213, 871–
878
[96] Seifarth C., Littmann L., Resheq Y., Röβner S.,
Goldwich A., Pangratz N., et al., MCS-18, a
novel natural plant product prevents autoimmune
diabetes, Immunol. Lett., 2011, 139, 58-67
[97] Apetrei N.S., Lupu A.-R., Calugaru A., Kerek F.,
Szegli G., Cremer L., The antioxidant effects
of some progressively puried fractions from
Helleborus purpurascens, Rom. Biotechnol.
Lett., 2011, 16, 6673-6681
[98] Păun-Roman G., Neagu E., Radu G.L.,
Membrane processes for the purication and
concentration of Helleborus purpurascens
extracts and evaluation of antioxidant activity,
Rev. Chim. (Bucharest), 2010, 61, 877-881
[99] Čakar J., Parić A., Vidic D., Haverić A.,
Haverić S., Maksimović M., et al., Antioxidant
and antiproliferative activities of Helleborus
odorus Waldst. & Kit, H. multidus Vis. and H.
hercegovinus Martinis, Nat. Prod. Res., 2011,
25, 1969–1974
[100] Trenin D.S., Volodin V.V., 20-hydroxyecdysone as
a human lymphocyte and neutrophil modulator:
In vitro evaluation, Arch. Insect Biochem.
Physiol., 1999, 41, 156–161
[101] Puglisi S., Speciale A., Acquaviva R., Ferlito G.,
Ragusa S., De Pasquale R., et al., Antibacterial
activity of Helleborus bocconei Ten. subsp.
284
M.C. Maior, C. Dobrotă
siculus root extracts, J. Ethnopharmacol., 2009,
125, 175–177
[102] Rosselli S., Maggio A., Formisano C., Napolitano
F., Senatore F., Spadaro V., et al., Chemical
composition and antibacterial activity of extracts
of Helleborus bocconei Ten. subsp. intermedius,
Nat. Prod. Commun., 2007, 2, 675–679
[103] Lindholm P., Gullbo J., Claeson P., Göransson
U., Johansson S., Backlund A., et al., Selective
cytotoxicity evaluation in anticancer drug
screening of fractionated plant extracts, J.
Biomol. Screen., 2002, 7, 333-340
[104] Muzashvili T., Skhirtladze A., Sulakvelidze T.,
Benidze M., Mshviladze V., Legault J., et al.,
Cytotoxic activity of Helleborus caucasicus A.
Br., Georg. Chem. J., 2006, 6, 684–685
[105] Jesse P., Mottke G., Eberle J., Seifert G., Henze
G., Prokop A., Apoptosis-inducing activity of
Helleborus niger in ALL and AML, Pediatr. Blood
Cancer, 2009, 52, 464-469
[106] Vochita G., Mihai C.T., Gherghel D., Iurea D.,
Roman G., Radu G.L., et al., New potential
antitumoral agents of polyphenolic nature
obtained from Helleborus purpurascens by
membranary micro- and ultraltration techniques,
SAAIC, 2011, 12, 41-51
[107] Büssing A., Schweizer K., Effects of a
phytopreparation from Helleborus niger
on immunocompetent cells in vitro, J.
Ethnopharmacol., 1998, 59, 139–146
[108] Smulders M.J.M., de Klerk G.J., Epigenetics in
Plant Tissue Culture, J. Plant Growth Regul.,
2011, 63 137–146
[109] Grabowski K., Schneider G., Properties and
Architecture of Drugs and Natural Products
Revisited, Curr. Chem. Biol., 2007, 1, 115-127
285
... 6 -9 Therefore, determining the chemotype of its dried powdered root has become an increasingly important task of interest in the area of analytical chemistry. 6,10,11 It seems that mainly responsible for the rhizome's cytotoxic activity is the cardiotonic steroid hellebrigenin and its glycosidic analog hellebrin. 11,12 Cardiotonic steroids exhibit an extremely attractive in vitro cytotoxic activity against both malignant and normal cell lines demonstrating a very promising therapeutic window as they selectively induce apoptosis rather to cancer than to normal cells. ...
... 11,12 Hellebrigenin/ Hellebrin pair is the sine qua non of the hellebores dried powdered root's chemotype since it is invariably present in 0.5%-1.5 % w/w concentration range. 5,6 Cardioactive steroids exhibit a very promising therapeutic window as they selectively induce apoptosis in cancer cells rather than normal cells, via binding to the cardioactive steroidbinding pocket on the extracellular segment of the transmembrane caveolae Sodium/Potassium ATPase pump. [13][14][15][16][17] From that point of view, our results regarding dried powdered root's extract therapeutic window are in accordance with cardioactive steroids -induced, malignant cell-selective documented, cytotoxicity. ...
... cardiac glycosides, steroidal saponins, ecdysones, and protoanemonin (Szabó 2005). Steroidal saponins have wide structural diversity as both furostan and spirostan skeleton structures (Challinor et al. 2012;Maior and Dobrotȃ 2013). Concentration of helleborin, the most wellknown cardioactive glycoside of hellebores, was found to be higher in H. purpurascens Waldst. ...
... Hellebore species have antioxidant potential (Pȃun-Roman et al. 2010;Apetrei et al. 2011;Č akar et al. 2011), and they can be used for heart failure in human therapy under medical control (Szabó 2005), for various diseases of the immune system (Szabó 2005;Horstmann et al. 2008;Littmann et al. 2008;Neacşu et al. 2010), as antitumoral agents (Vochita et al. 2011), for diabetes, eczema, toothache, and arthritis (Maior and Dobrotȃ 2013). ...
Article
Full-text available
The use of hellebore (Helleborus) species for medical purposes has a long-standing tradition. Our work aimed at providing a historical survey of their medicinal application in Europe, and data on current ethnobotanical use of H. purpurascens Waldst. et Kit. in Transylvania (Romania), compared with earlier records of this region and other European countries. While the chemistry and pharmacology of hellebores have been researched extensively, little is known about their anatomical traits. Thus, we intended to provide a detailed histological analysis of Helleborus odorus Waldst. et Kit., H. purpurascens, and H. niger L., based on transverse sections of aerial parts and root. Our survey revealed that H. purpurascens is known for immunotherapy, wounds, and as antiemetic drug in ethnoveterinary medicine, but not in human therapy in the study area. Distinctive histological characters included diverse stele structure in the root; sclerenchymatous bundle caps around compound vascular bundles in the stem and the main leaf veins of H. odorus; and amphistomatic leaves in H. purpurascens. Quantitative vegetative traits also revealed significant differences among species, but they may reflect environmental influences, too. In all three species the sepal was hypostomatic with mesomorphic stomata, while the modified petal comprised a proximal nectar-producing and a distal non-secretory part. Distinctive floral traits included shape of modified petal, presence of papillae and thickness of non-secretory part; as well as ornamentation of tricolpate pollen grains. Our findings suggest that the anatomy of various plant parts varies slightly with each species, including ethnomedicinally known H. purpurascens, even though the basic structure is the same within the genus.
... Helleborus species are herbaceous species found in the temperate zone in Europe. Their chemical composition includes cardiotonic glicosides bufadienolidic-type (e.g., hellebrin), steroidal saponins, ecdisteroids, and gamma-lactones, as protoanemonin [127]. In Romanian folk medicine, the root is used to treat respiratory infections in pigs and sheep [128]. ...
Article
Full-text available
Background. Nowadays, phytotherapy offers viable solutions in managing respiratory infections, disorders known for considerable incidence in both children and adults. In a context in which more and more people are turning to phytotherapy, finding new remedies is a topical goal of researchers in health and related fields. This paper aims to identify those traditional medicinal plants that show potentially antibacterial effects against four Gram-negative germs (Chlamydia pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae, and Moraxella catarrhalis), which are considered to have high involvement in respiratory infections. Furthermore, a comparison with Romanian folk medicines was performed. Methods. An extensive review of books and databases was undertaken to identify vegetal species of interest in the context of the topic. Results. Some traditional Romanian species (such as Mentha × piperita, Thymus vulgaris, Pinus sylvestris, Allium sativum, Allium cepa, Ocimum basilicum, and Lavandula angustifolia) were identified and compared with the plants and preparations confirmed as having antibacterial effects against specific germs. Conclusions. The antibacterial effects of some traditionally used Romanian medicinal plants are poorly investigated, and deserve further attention.
... On the basis of morphological similarity with the genus Helleborus L., some investigators have assigned Eranthis to the tribe Helleboreae DC., subtribe Helleborinae Jensen [49][50][51]. On the other hand, ongoing research in the field of Helleborus phytochemistry indicates that a distinctive feature of this genus is the accumulation of substances from the class of cardioactive glycosides: cardenolides and bufadienolides [52], which have not been found in Eranthis species. In phytochemical characteristics, Eranthis is closer to the genus Actaea because chromones are synthesized in these genera via normal physiological processes [53]. ...
Article
Full-text available
Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranuncu-laceae Juss.)-collected from natural populations of Kyrgyzstan-were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono-and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid-related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Couma-rins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3′-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chro-mones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family.
... For this reason, studies on the phytochemical structure and phytochemical properties of Helleborus species have been of interest in the last few years. There are studies including inherent extracts from these species which indicate that Helleborus plants are a helpful origin of chemical compounds with excellent therapeutic potency years [1]. ...
Article
Full-text available
The aims of the present study were to evaluate the antioxidant activity and DNA Protective effect of Helleborus orientalis (HO) leaf extract against oxidative damage, and to determine the total phenolic and flavonoid contents of the plant species studied. Original Research Article Öztürk et al.; AJBGMB, 1(4): 1-12, 2018; Article no.AJBGMB.47680 2 Methods: The total phenol content (TPC) of H. orientalis (Ranunculaceae) extract was determined using the Folin-Ciocalteu technique. The aluminum chloride colorimetric assay in the determination of The total flavonoid content (TFC) and was used, Analysis of Phenolic Acids was identified by High-Performance Liquid Chromatography (HPLC). Antioxidant activity was analyzed by the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) Assay. Protective effect of H. orientalis leaf extract against to H 2 O 2 was evaluated by using TAS, TOS methods and Comet assay. Key Findings: H. orientalis ethanol extracts contain high amounts of antioxidants. The HO leaf methanol extract (LME) decreased the DNA damage at all tested concentrations in a dose-dependent manner (r=0.86 p<0.01) against to H 2 O 2. Conclusions: The total phenol content in the extracts of different parts of the plant varied from 4.00 mg GAE/1 gr to 19.42 mg GAE/1 gr. The flowers had the highest phenol content (19.42 mg GAE/1 gr sample) and followed by the leaves (17.20 mg GAE/1 gr sample). The total flavonoid content in the extracts from different parts of the plant varied from 2.57 mg QE/1 gr to 11.88 mg QE/1 gr. The flowers had the highest flavonoid content (11.88 mg QE/1 gr sample) and followed by the leaves (10.21 mg QE/1 gr sample). Antioxidant activity of fractions was explained as a percentage of DPPH radicals' scavenging and IC 50 values (μg/ml). Leaf and flowers of HO are richer in antioxidant than its root and stem. As the concentration of leaf extracts used increased, the DNA protective effect increased and it was statistically significant at overdoses of 2500 μg/mL. Total antioxidant status (TAS) levels were significantly (p <0.05) decreased in the H 2 O 2 group (3.4±0.21) but H. orientalis was significantly (p<0.05) increased TAS levels in this group. When the concentration of leaf extracts used increased, the protective effect has also increased and statistically significant at overdoses of 2500 μg / mL (6.3±0.67). Total oxidant status (TOS) levels were significantly (p <0.05) increased in the H 2 O 2 group (25.3±0.74) and H. orientalis was significantly (p<0.05) decreased TOS levels in groups.
Article
Ethnopharmacological relevance: In Romanian folk medicine, Helleborus niger L. is used for the treatment of rheumatoid arthritis or viral infections and in complementary therapy, especially in anthroposophic medicine (AM), where the plant is administered as an adjuvant to treat malignant diseases. In the present study, we investigated the differential cytotoxic effects of H. niger on human tumour and healthy cells of the human immune system in vitro. Material and methods: Protoanemonin and saponins, as significant constituents of H. niger extracts, were quantified in five individual batches using validated HPLC methods. Further, the impact of H. niger on proliferation capacity (MTT assay) as well as on apoptosis and necrosis induction in a panel of tumour cell lines and human lymphocytes (combined annexin V and propidium iodide staining) was monitored. In addition, NK cell function (degranulation-CD107a assay and IFN-gamma secretion) was also investigated since these immunocompetent cells are important for the control of malignancies within the human body. Results: Extracts of H. niger induced proliferation inhibition not only of lymphoblastic leukaemia cells (MOLT4; IC50: 171 µg/mL) but also of myosarcoma (SK-UT-1b; IC50: 304 µg/mL) and melanoma cells (HT-144; IC50: 569 µg/mL) due to the induction of apoptosis. Purified T cells or NK cells were significantly affected through the presence of high H. niger concentrations while bulk lymphocytes were not affected. NK cells' anti-tumour functions expressed by degranulation capacity as well as IFN-y production were unaffected by the presence of the H. niger extract. Since protoanemonin and saponins have been reported in the literature to exert cytotoxic effects, their content was also determined. Conclusions: H. niger extracts exhibit differential cytotoxicity towards tumour cell lines and healthy human T- and NK-cells.
Article
Full-text available
This study aim was to prove the efficiency of ultrafiltration process for the concentration of Helleborus purpurascens extracts and to evaluate the extract antioxidant activity. The aqueous and hydro alcoholic extracts of H. purpurascens were concentrated by a multi-stages ultrafiltration cascade, as a novelty in medicinal plant processing. The results revealed that the concentrated extracts have a high antioxidant activity (over 70% DPPH inhibition for hellebore concentrated aqueous extract and over 78% DPPH inhibition for hellebore concentrated hydro alcoholic extract), thus it can be considered a good source for further medicinal applications.
Article
Full-text available
Phytotherapy, as form of traditional and conventional veterinary medicine, includes curing, alleviation and prevention the onset of diseases in animals based on natural medicinal raw materials and folk remedies made from plants. In animal health care, the use of medicinal and other plants as supporting therapy, in preventive purposes or as a complete therapy has a large potential regardless whether it is the question of individual or combined plant medicinal preparations which act synergistically. Phytotherapy is very intensively used in prophylactic purposes and with the aim of treatment of milder forms of diseases, chronic diseases and recurrent infections as well as in organic livestock production. Extracts and preparations from different plants are used with the aim of intensifying the activity of immune system and stimulations some functions of organism. The great number of herb metabolites shows antimicrobial and antiparasitic activity and gives the positive effects in the treatment of ectoparasitoses and endoparasitoses. This research paper gives a review of the plants most frequently used in ethnoveterinary medicine for health purposes of farm animals.
Article
Helleborus bocconei Ten. subsp. intermedins (Ranunculaceae) is a Sicilian medicinal plant used for the treatment of pneumonia affecting cows and horses and for the removal of human decayed molars. The goal of our study was to assess the biological activity of Helleborus bocconei subsp. intermedins by testing its extracts for their activity against bacteria known to cause respiratory diseases. The two more active extracts (light petroleum from roots and aerial parts), as well as the dichloromethane extracts, were analyzed by GC/MS and their composition is reported.
Article
Medicinal Natural Products: A Biosynthetic Approach, Third Edition, provides a comprehensive and balanced introduction to natural products from a biosynthetic perspective, focussing on the metabolic sequences leading to various classes of natural products. The book builds upon fundamental chemical principles and guides the reader through a wealth of diverse natural metabolites with particular emphasis on those used in medicine. There have been rapid advances in biosynthetic understanding over the past decade through enzymology, gene isolation and genetic engineering. Medicinal Natural Products has been extended and fully updated in this new edition to reflect and explain these developments and other advances in the field. It retains the user-friendly style and highly acclaimed features of previous editions: A comprehensive treatment of plant, microbial, and animal natural products in one volume. Extensive use of chemical schemes with annotated mechanistic explanations. Cross-referencing to emphasize links and similarities. boxed topics giving further details of medicinal materials, covering sources, production methods, use as drugs, semi-synthetic derivatives and synthetic analogues, and modes of action. Medicinal Natural Products: A Biosynthetic Approach, Third Edition, is an invaluable textbook for students of pharmacy, pharmacognosy, medicinal chemistry, biochemistry and natural products chemistry.
Article
Plant saponins are a group of naturally occuring triterpene or steroid glycosides which include a large number of biologically and pharmacologically active compounds. Saponins have been shown in both in vitroand in vivoexperimental test systems during the last decade to possess a broad spectrum of biological and pharmacological activities. This review will summarize some of the recent advances concerning cancer-related activity, immunostimulating, immunoadjuvant, antihepatotoxic, antiphlogistic, antiallergic, molluscicidal, hemolytic, antifungal, antiviral, and hypoglycemic activities. In addition, the effects on the cardiovascular system and the central nervous system will be discussed together with other miscellaneous effects. Studies of structure/activity relationships and mechanism of action will be presented.
Article
A phytochemical analysis has been carried out on theglycoside-enriched fraction of a McOH extract of Helleborus orientalis rhizomes, resulting in the isolation of two new bisdesmosidic furostanol saponins (1 and 2) and two new furospirostanol saponins (3 and 4). The structures of 1-4 were determined on the basis of extensive spectroscopic analysis and acid hydrolysis followed by chromatographic and spectroscopic analysis. Compound (3) showed moderate cytotoxic activity against HSC-2 human squamous cell carcinoma cells with an IC50 value of 16 μg/mL.