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Genus Enterolobium : traditional uses, chemistry and biological activities Genus Enterolobium: traditional uses, chemistry and biological activities

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Keywords: Enteroobium, traditional uses, chemical constituents and biological activities The chemical composition, pharmacological activity and traditional uses of 20 species attributed to the genus Enterolobium (Fabaceae) as used in the South and Central America, and Tropical Africa, were revised and compared. A survey of the available literature shows that these species are used mostly for their anti-inflammatory and cytotoxic activities. Additionally, some of these Enterolobium species showed antibacterial, antifungal, insecticidal, molluscicidal and larvicidal activities. Generally, the triterpenes or the phenolic compounds isolated from these plant extracts are assumed to be the bioactive principles.
Archives of Pharmaceutical Sciences 2017; Vol. 1(1):16-25
Research Article
Genus Enterolobium: Traditional uses, chemistry, and biological activities
Mariam I. Gamal El-Dina, Omayma A. Eldahshana, Abdel-Nasser B. Singaba*,
and Nahla A. Ayoubb
aDepartment of Pharmacognosy, Faculty of Pharmacy, Ain-Shams University, Cairo, 11566, Egypt.
bDepartment of Pharmacognosy, Faculty of Pharmacy, British University in Egypt (BUE), Egypt.
ABSTRACT
The chemical composition, pharmacological activity and traditional uses of 20 species attributed to the genus
Enterolobium (Fabaceae) as used in the South and Central America, and Tropical Africa, were revised and
compared. A survey of the available literature shows that these species are used mostly for their anti-inflammatory
and cytotoxic activities. Additionally, some of these Enterolobium species showed antibacterial, antifungal,
insecticidal, molluscicidal and larvicidal activities. Generally, the triterpenes or the phenolic compounds isolated
from these plant extracts are assumed to be the bioactive principles.
Keywords: Enteroobium; traditional uses; chemical constituents; biological activities.
*Correspondence | Prof. Dr. Abdel Nasser B. Singab; Department of Pharmacognosy, Faculty of Pharmacy, Ain Shams University, African
union organization street Abassia, 11566, Cairo, Egypt. Email: Abdelnasser.sengab@pharma.asu.edu.eg; dean@pharma.asu.edu.eg
Citation | Mariam IG, Omayma AE, Abdel-Nasser BS, and Nahla AA. 2017. Genus Enterolobium: traditional uses, chemistry and biological
activities. Arch Pharm Sci 1(1): 16-25
DOI: 10.21608/aps.2017.10358
Online ISSN: 2356-8380
Print ISSN: 2356-8399
Journal no. 1
Copyright: © 2017 Gamal El-Din et al. This is an open-access article licensed under a Creative Commons Attribution 4.0 International License
(CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author(s) and source are
credited.
Published by: Ain Shams University, Faculty of Pharmacy.
1. INTRODUCTION
In recent times, interest in plant research has
increased all over the world owing to its potential
use in traditional systems of medicine for treating
a wide variety of diseases. Various medicinal
plants have been identified and modern scientific
approaches have been used to study their
authenticity, safety, and efficacy of their
therapeutic use. The results highlight the great
potential of medicinal plants in the field of
pharmacology. Enterolobium is an important
genus of family Fabaceae belongs to subfamily
Mimosoideae. It comprises 12 species of
flowering plants native to tropical and warm-
temperate regions of the Americas. They are
medium-sized to large trees. Some of these
Enterolobium sp, including, Enterolobium
timbouva are cultivated in Egypt [1]. Genus
Enterolobium is closely related to Albizia and
Samanea and is probably only maintained as a
separate genus due to its widespread cultivation.
The focus of this review is to provide information
on the structures and biological activities of
compounds isolated and identified from genus
Enterolobium.
2. MATERIALS AND METHODS
Genus Enterolobium: Traditional uses, chemistry, and biological activities
17
The pharmacological activities of compounds
isolated and identified from Enterolobium were
searched through SciFinder that retrieves
information in databases produced by Chemical
Abstracts Service (CAS) as well as the
MEDLINE database of the National Library of
Medicine. The CAS databases are CAplusSM
(reference database), REGISTRYSM (chemical
structure database), CASREACT® (chemical
reaction database), CHEMCATS® (commercial
source database), and CHEMLIST® (regulatory
database). The data were updated in Septemper
2016, using biological activities or chemical
constituents and Enterolobiumas keywords.
3. RESULTS AND DISCUSSION
3.1. Chemical constituents
Deep reviewing of literature concerning genus
Enterolobium revealed the isolation and
separation of different following classes of
compounds:
3.1.1 Triterpenes
Marx and Trusch, 1963, isolated lupeol (1)
and lupeyl acetate (2) from the hexane fraction of
E. contortisiliquum [1]. Marx and Trusch, 1967,
isolated triterpene of the β-amyrin type, the
lactone of machaerenic acid from the fruits of E.
contortisiliquum [2]. Delgado et al., 1984,
isolated the triterpenes -hydroxy-21β-E-
cinnamoyl-oxyolean-12-en-20-oic acid (3), 3β,
21β-dihydroxyolean-12-en-28-oic acid
(machaerinic acid) (4) and its lactone (3β-
hydroxyolean-12-en-21β→28-lactone) (5) from
the fruits of E. contorstisiliquum. Methyl and
ethyl esters of 3β, 21β-dihydroxyolean-12-en-oic
acid was isolated and characterized as artifacts
[3] as shown in figure Fig. 1
Mimaki et al., 2003, isolated two triterpene
bisdesmosides, designated as enterolosaponins A
(6) and B (7), from the n-butanol soluble fraction
of the aqueous extract of the pericarps of E.
contortisiliquum as shown in Fig. 2 [4].
Mimaki et al., 2004, isolated seven
bisdesmosidic triterpene saponins, with up to
eight monosaccharides, which were given the
trivial names contortisiliosides A→G (8-14) from
the n-butanol soluble fraction of the aqueous
extract of the pericarps of E. contortisiliquum [6]
as shown in Fig. 3.
Fig. 1 Chemical structures of compounds (1-5) isolated from
E. contortisiliquum
Mariam I. Gamal El-Din, et al. Arch Pharm Sci 1(1): 16-25
18
Fig. 2 Chemical structures of Enterolosaponins A (6) (R= α-
l-arabino-furanosyl group) and Enterolosaponins B (7) (R=
H) isolated from E. contortisiliquum
Fig. 3 Chemical structures of compounds (8-14) isolated
from E. contortisiliquum
Fig. 4 Chemical structures of compounds (15-20) isolated
from E. contortisiliquum
Triterpenes maslinic acid (15), betulinic acid
(16), 3-oxo-β-amyrin (17), ursolic acid (18), β
amyrin (18), lupeol (19) and squalene (20) Fig. 4
were isolated from the fruits of Enterolobium
contortisiliquum [5]. Hanna, 1981, identified
three saponins from E. cyclocarpum. All have
machaerenic acid aglycone, differing in their
sugar moiety either glucosylgalactose or rhamno-
galactoside or glucoside [6].
3.1.2 Phenolics
Ten phenolic compounds were isolated for the
first time from Enterolobium contortisiliquum
leaf extract including 3,4-Dihydroxy-Cinnamic
acid (Caffeic acid) (21); Quercetin-3-O-β-D-
glucopyranoside (Isoquercitrin) (22); Quercetin-
3-O-β-D-galactopyranoside (Hyperin) (23);
Kaempferol-3-O-β-Dglucopyranoside
(Astragalin) (24); Hesperetin-7-O-rutinoside
(Hesperidin) (25); Quercetin 3-O-rutinoside
(Rutin) (26); Quercetin (27); Kaempferol (28); 7-
methoxycoumarin (Herniarin) (29); and Chrysin
(30) Fig. 5 [7]. Gallic acid, protocatechuic acid,
quercetin-7-rutinoside, catechin, isovitexin, and
quercetin were isolated from Enterolobium
contortisiliquum pods using polyamide column
fractionation. Besides, HPLC analysis of the
phenolic fraction revealed the presence of
pyrogallol, syringic and p-coumaric acids [8].
Fig. 5 Chemical structures of compounds (21-30) isolated
from E. contortisiliquum
Genus Enterolobium: Traditional uses, chemistry, and biological activities
19
3.1.3 Fatty Acids
Ikechukwu et al., 1998, studied 15 tropical
seeds gathered in Nigeria including Enterolobium
cyclocarpium seeds to determine their fat content
and the fatty acid composition of their oils. The
oil of Enterolobium cyclocarpium was found to
contain high proportions of linoleic and oleic acid
as well as palmitic and linolenic acid. It was
assumed that some of these less familiar wild
seeds could be used as sources for industrial or
edible oils, provided that possible toxic
constituents could be removed [9]. GC-MS
analysis of unsaponifiable matter of
Enterolobium contortisiliquum revealed that α-
and β-amyrin and 4-methyl 2, 6-di-tert-
butylphenol are the main components, while
palmitic and 9, 12-octadecadienoic acids were the
major fatty acids [10].
3.1.4 Essential oils
Shahat et al., 2006, isolated essential oils from
seeds of Enterolobium contortisiliquum. Seeds of
Enterolobium contortisiliquum were subjected to
steam distillation to obtain a light yellow
essential oil in a yield of 3 ml/kg of seeds. The
major components of the oil were identified using
gas chromatography/mass spectrometry (GC-MS)
and were furfural, limonene, linalool, estragole,
carvone, and apiole with carvone representing
more than 50% of the total composition [11].
3.1.5 Carbohydrates
Oliveira, Silva et al. 2001, investigated the
composition, structure and rheological properties
of Enterolobium contortisilliquum gum. The gum
proved to contain galactose, arabinose, rhamnose
and glucuronic acid as main monosaccharide
components. 13C nuclear magnetic resonance
spectroscopy revealed that the anomeric
composition is similar to the Enterolobium
cyclocarpum exudate; however, no 4-O-
methylglucuronic acid was detected for E.
contortisilliquum [12]. Nine sugar components
were identified in hydrolysate of Enterolobium
contortisilliquum mucilage with glucose
(34.89%), xylose (6.78%) and rhamnose (5.98%)
being the predominant sugars by GLC [10]. Oliva
et al. 1987 carried out a structural study of the
gum exudate from Enterolobium cyclocarpum
using chemical methods and 13C NMR
spectroscopy. The results revealed that the
structure of this gum is essentially a beta-(1-->3)-
galactan. Some galactoses are 6-O-linked and
others also occur as terminal residues. There is
evidence that supports the presence of alpha-L-
arabinofuranose and beta-L-arabinopyranose.
The beta-d-glucuronic acid may be present as
terminal and internal residues, while the 4-O-
methyl-alpha-D-glucuronic acid residues exist
predominantly in internal positions [13].
3.2 Biological activities of genus Enterolobium:
3.2.1 Cytotoxic activity
The aqueous alcohol extract of Enterolobium
contortisilliquum leaves exhibited potent
cytotoxic activity against different cancer cell
lines with IC50 values of 2.67 μg/mL against
MCF-7 cell line, 3.89 μg/mL against HCT116
cells, 4 μg/mL against HEp2 cells, 4.5 μg/mL
against HeLa cells, 1.7 μg/mL against PC-3 cells,
and 5.7 μg/mL against Huh-7 cells. In vitro
cytotoxic assay of the isolated pure compounds
against Huh-7 cell Line showed that compounds
1, 9 and 10 are the only tested compounds
exhibiting potent cytotoxic activity with IC50 of 3
μg/mL, 0.76 μg/mL, and 18.51 μg/mL
respectively. The rest of the tested compounds
exhibited IC50 exceeding 1000 μg/mL which
reflects their safety [1]. Mimaki et al., 2003,
examined the cytotoxic activities of
enterolosaponins A and B isolated from E.
contortisiliquum against BAC1.2F5 mouse
macrophages, EL-4 mouse lymphoma cells, and
L-929 mouse fibroblasts. Although
enterolosaponin B and the de-(E)-cinnamoyl
derivative of enterolosaponin A did not show any
apparent cytotoxic activities against all the cell
lines, enterolosaponin A exhibited a highly
Mariam I. Gamal El-Din, et al. Arch Pharm Sci 1(1): 16-25
20
selective cytotoxicity against BAC1.2F5 mouse
macrophages with an LD50 value of about 3 μM.
The cinnamoyl group attached to the C-21β-
hydroxyl group and the terminal α-l-arabino-
furanosyl groups were considered to be essential
for the selective cytotoxicity [6]. It should be
notable that the macrophage death caused by
enterolosaponin A was shown to be neither
necrotic nor apoptotic from the morphology of
the dead cells, whose cytosol occurred in
vacuolation. Although the precise mechanism is
unknown, one possibility could be raised that
enterolosaponin A caused fusion of endosomal
membranes to make the large vacuole structure
after it internalized by macrophages. Mimaki et
al., 2004, evaluated for the cytotoxic activities of
the seven triterpene saponins (contortisiliosides
A-G) isolated from E. contortisiliquum against
BAC1.2F5 mouse macrophages, EL-4 mouse
lymphoma cells, and L-929 mouse fibroblasts.
Whereas contortisiliosides A and C were
moderately cytotoxic to both BAC1.2F5
macrophages and EL-4 cells, and
contortisiliosides D-G did not show any apparent
cytotoxic activities against the three cell lines,
contortisilioside B exhibited selective cytotoxic
activity against BAC1.2F 5 mouse macrophages,
with an IC50 value of 3.4 μM [14]. The above
results imply that the cinnamoyl group at C-(21)
of the aglycone is essential for the cytotoxicities
against macrophages and lymphoma cells. The
selective cytotoxicity against macrophages is
particularly sensitive to the structures of the
oligosaccharide moieties. It should be noted that
the macrophage death caused by contortisilioside
B was shown to be neither necrotic nor
apoptosis-inducing according to the unique
morphological change of the dead cells, whose
cytosols were converted into large vacuolar
structures. Oliva et al., 2007, identified and
characterized proteinase inhibitors from the seed
of E. contortisiliquum that can be used to prevent
proteolysis of the extracellular matrix in the
treatment of cancer. The inhibitors have distinct
spectra of inhibition and show different levels of
effectiveness in inhibiting the growth of tumor
cell lines in culture. They interacted
synergistically with 5-fluorouracil in the
inhibition of tumor cell growth [15].
Nakahata et al., 2011, stated that
supplementary to the efficient inhibition of
trypsin, chymotrypsin, plasma kallikrein, and
plasmin already described by E. contortisiliquum
Trypsin Inhibitor (EcTI) from E.
contortisiliquum, it also blocks human neutrophil
elastase and prevents phorbol ester (PMA)-
stimulated activation of matrix metalloproteinase
(MMP)-2 probably via interference with
membrane-type 1(MT1)-MMP. Moreover,
plasminogen-induced activation of proMMP-9
and processing of active MMP-2 was also
inhibited. Furthermore, the effect of EcTI on the
human cancer cell lines HCT116 and HT29
(colorectal), SkBr-3 and MCF-7 (breast), K562
and THP-1 (leukemia), as well as on human
primary fibroblasts and human mesenchymal
stem cells (hMSCs) was studied. EcTI inhibited
rather specifically tumor cell viability without
targeting primary fibroblasts and hMSCs. It was
stated that the polyspecific proteinase inhibitor
EcTI prevents proMMP activation and is
cytotoxic against tumor cells without affecting
normal tissue remodeling fibroblasts or
regenerative hMSCs being an important tool in
the studies of tumor cell development and
dissemination. de Paula et al., 2012, studied the
effect of the plant proteinase inhibitor (EcTI)
from E. contortisiliquum, on the adhesion,
migration, and invasion of gastric cancer cells.
EcTI showed no effect on the proliferation of
gastric cancer cells or fibroblasts but inhibited the
adhesion, migration and cell invasion of gastric
cancer cells, however, had no effect upon the
adhesion of fibroblasts. EcTI was shown to
decrease the expression and to disrupt the cellular
organization of molecules involved in the
formation and maturation of invadopodia, such as
integrin β1, cortactin, N-WASP, MT1-MMP, and
MMP-2. Moreover, gastric cancer cells treated
Genus Enterolobium: Traditional uses, chemistry, and biological activities
21
with EcTI presented a significant decrease in
intracellular phosphorylated Src and FAK,
integrin-dependent cell signaling components
[16]. Together, these results indicate that EcTI
inhibits the invasion of gastric cancer cells
through alterations in integrin-dependent cell
signaling pathways. The aqueous alcohol extract
of Enterolobium contortisilliquum leaves
exhibited potent cytotoxic activity against
different cancer cell lines with IC50 values of 2.67
μg/mL against MCF-7 cell line, 3.89 μg/mL
against HCT116 cells, 4 μg/mL against HEpG2
cells, 4.5 μg/mL against HeLa cells, 1.7 μg/mL
against PC-3 cells, and 5.7 μg/mL against Huh-7
cells. In vitro cytotoxic assay of the isolated pure
compounds against Huh-7 cell Line showed that
compounds 1, 9, and 10 are the only tested
compounds exhibiting potent cytotoxic activity
with IC50 of 3 μg/mL, 0.76 μg/mL, and 18.51
μg/mL, respectively. The rest of the tested
compounds exhibited IC50 exceeding 1000 μg/mL
which reflects their safety [1].
The cytotoxicity of the methanolic extract of
Enterolobium cyclocarpum leaves was
investigated using the brine shrimp lethality
assay, MTT assay using cervical (HeLa) and
breast (MCF7) cancer cell lines, cell cycle
analysis and Annexin V-FITC/PI assay. The
extract showed cytotoxic activity with the LC50
value of 31.63 μg/mL. Significant growth
inhibition was observed in both cell lines with
IC50 values of 2.07±1.30 μg/mL and 11.84±1.18
μg/mL for HeLa and MCF7, respectively. Cell
cycle analysis indicated that HeLa cells were
arrested in the G2/M phase while MCF7 cells
arrested in the G1/G0 phase. The Annexin V-
FITC/PI assay revealed phosphatidylserine
translocation in both cell lines and thus apoptosis
induction upon treatment with the extract. The
crude extract (70% alcohol) of Enterolobium
contortisiliquum pods and the saponin fraction
exhibited potent cytotoxic activity on HepG2
(IC50 14 and 29 μg/mL) and MCF7 (IC50 16 & 31
μg/mL) cell lines [18]. The mucilage and
petroleum ether fractions showed cytotoxicity
activity on HepG2 with (IC50 19 & 61 μg/mL),
while phenolic fraction showed cytotoxicity
towards MCF7 cells with the IC50 value of 79
μg/mL [12].
3.2.2 Inflammatory activity
Castro-Faria-Neto et al., 1991, investigated
the pro-inflammatory activity of enterolobin, a
hemolytic protein from E. contortisiliquum seeds.
In doses ranging from 1 to 20 μg/site, enterolobin
induced a dose-dependent paw edema and
pleurisy in rats. One hour after the intrathoracic
injection of enterolobin, the total leukocyte
content of the pleural cavity increased
significantly, mainly due to mononuclear and
neutrophil accumulation. At 24 h, although the
no. of mononuclear and neutrophil cells tended to
decrease, a great rise in eosinophil counts was
noted. Intraperitoneal treatment with the dual
lipoxygenase and cyclooxygenase blockers, BW
755c (25 mg/kg) and NDGA (50 mg/kg), or the
corticosteroid dexamethasone (0.1 mg/kg)
inhibited enterolobin-induced paw edema by 35,
38, and 47% resp., whereas indomethacin (2
mg/kg) was inactive. The H1 antagonist,
meclizine (25 mg/kg), was also effective against
enterolobin edema, while the PAF antagonists
WEB 2086 and PCA 4248 (20 mg/kg) did not
modify the reaction. It was concluded that
enterolobin is a potent inducer of pleural
exudation, cellular infiltration, and paw edema.
Furthermore, enterolobin-induced edema is
partially dependent on lipoxygenase metabolites
and histamine, while PAF and prostaglandins did
not seem to be important in this reaction [19].
3.2.3 Insecticidal, molluscicidal and larvicidal
activities
Rehr et al., 1973, studied the presence of
insecticidal amino acids in different legume
seeds. They stated that certain legumes are free
from predation on their seeds due to the presence
of insecticidal amino acids in these seeds. E.
cyclocarpum seeds proved to be one of those
Mariam I. Gamal El-Din, et al. Arch Pharm Sci 1(1): 16-25
22
seeds due to the presence of albizziine amino
acid [H2NCONHCH2CH(NH2)COOH]. Soussa et
al., 1993, tested for the toxic effects enterolobin,
the cytolytic and inflammatory protein isolated
from E. contortisiliquum seeds, on larvae of the
coleopteran Callosobruchus maculatus and the
Lepidopteran Spodoptera littoralis [21].
Bioassays performed with enterolobin
incorporated into artificial seeds showed that the
phytocytolysin was toxic to larvae of C.
maculatus, and proved to be innocuous to S.
littoralis larvae. In vitro proteolysis studies using
larval gut enzymes, analyzed on SDS-PAGE,
showed that only S. littoralis proteases could
digest enterolobin, suggesting that the insect's
digestive proteases were able to inactivate the
cytolysin before it could exert any toxic effect. C.
maculatus proteases, on the other hand, were
unable to hydrolyze enterolobin. The mechanism
of toxicity of enterolobin did not appear to
involve any damage to the microvilli of the
epithelial gut cells of C. maculatus as shown by
electron microscopy. Some tentative hypotheses
are considered in order to explain the toxic
mechanism of action of enterolobin towards C.
maculatus. Moura et al., 2007, purified Chitin-
binding vicilin from E.contortisiliquum seeds by
ammonium sulfate followed by gel filtration on
Sephacryl 300-SH and on Sephacryl 200-SH. The
vicilin, called E.contortisiliquum vicilin (EcV), is
a dimeric glycoprotein. It was tested for anti-
insect activity against Callosobruchus maculatus
and Zabrotes subfasciatus larvae and for
phytopathogenic fungi, Fusarium solani and
Colletrichum lindemuntianum. EcV was very
effective against both bruchids, and also exerted
an inhibitory effect on the germination of F.
solani at concentrations of 10 and 20 μg mL-1
[20]. Farias et al., 2010, assessed the toxicity of
seed water extracts of 15 leguminous species
including E.contortisiliquum upon Aedes aegypti
larvae responsible for dengue and yellow fever.
A partial chemical and biochemical
characterization of water extracts, as well as
assessment of their acute toxicity in mice, were
performed. E.contortisiliquum extract, as well as
other three leguminous species, extracts caused
100% of larval mortality after 1 to 3 h of
exposure. The extracts showed low toxicity to
mice (LD50 > 0.15 ± 0.01 g/kg body weight), but
despite these promising results, further studies
are necessary to understand the toxicity of these
extracts and their constituents from primary and
secondary metabolism upon Aedes aegypti [22].
3.2.4 Spermicidal activity
Elbary and Nour, 1979, investigated the
spermicidal effects of saponins isolated from E.
cyclocarpum. They showed that all saponins
tested were spermicidal independent on their
nature.
3.2.5 Antifungal activity
Quiñones et al., 1995, tested the antifungal
activity of ethanol and water extracts from the
heartwood of E. cyclocarpum. The fungi tested
were Trametes versicolor (white rot), Coniophora
puteana (brown rot), Chaetomium globosum (soft
rot) and the mold-fungus Trichoderma viride.
Only the ethanol extract showed a distinct
fungistatic effect, even at low concentrations. But
the water extract had no impact on fungal growth
[23].
3.2.6 Hepatogenous photosensitization activity
Grecco et al., 2002, reported three outbreaks
of hepatogenous photosensitization in cattle
caused by E. contortisiliquum pods. Clinical
signs were anorexia, depression, photo-
sensitization, and abortion. Most affected cattle
recovered in 30-40 days. At necropsies, the liver
was present, the gallbladder was enlarged and
edematous, and numerous seeds of E.
contortisiliquum were in the forestomachs and
abomasum. Fruits of the plants administrated to 2
calves produced clinical signs and 2/4 died.
Clinical chemistry, gross necropsies, and
histopathology confirmed gastrointestinal
irritation and liver degeneration. One calf dosed
Genus Enterolobium: Traditional uses, chemistry, and biological activities
23
with only E. contortisiliquum leaves did not
develop clinical signs [24].
3.2.7 Antimicrobial activity
The antibacterial activity of different fractions
of E. contortisiliquum fruit extract was evaluated
against seven Gram-positive and six Gram-
negative microorganisms using the agar well
diffusion assay method. Maximum inhibition was
observed with compounds at 1 mg/mL; catechin
and protocatechuic acid against Pseudomonas
aeruginosa (-ve) (14.5 and 17 mm, respectively)
while, the crude and petroleum ether extracts
showed antimicrobial activity against
Micrococcus luteus (+ve) (inhibition zone 12 and
10 mm, respectively). Whereas, polysaccharide
and protein exhibited antimicrobial activity
against Klebsiella pneumonia (-ve) (16 and 13
mm, respectively) [10]. Shahat et al., 2008,
evaluated for the antimicrobial activities of the
essential oil isolated from seeds of E.
contortisiliquum.
The antimicrobial activities were determined
against four species of Gram-positive bacteria
(Bacillus subtilis, Bacillus cereus,
Staphylococcus aureus, Micrococcus luteus) and
two Gram-negative bacteria (Klebsiella
pneumoniae, Serratia Marcescencs). The
essential oil inhibited the growth of all tested
bacteria but was most effective against the gram-
positive bacteria. Chemicals that are responsible
for the antibacterial effect of the essential oil
were determined using the bio-autography thin
layer chromatography (TLC) technique. The
active compounds responsible for the activity
were found to be carvone and estragole.
3.2.8 Proteinase inhibitor
Oliva et al., 1987, purified two types of
proteinase inhibitors from E. contortisiliquum
beans. The inhibitor of serine proteinases
inhibited trypsin, chymotrypsin, and plasma
kallikrein, but not tissue kallikreins. The 2nd
inhibitor, with activity directed against
mercaptoproteinases, was isolated by CM-
papain-Sepharose. Papain and bromelain were
inhibited [24]. Sampaio et al., 1992, studied
serine proteinase inhibitors, in the seeds of E.
contortisiliquum using bovine trypsin, Factor
XIIa, and human plasma kallikrein. E.
contortisiliquum inhibitor inactivated all three
enzymes. It was assumed that the trypsin
inhibitor isolated from E. contortisiliquum, is of
the Kunitz type [25]. Batista et al., 1996, isolated
a trypsin inhibitor from E. contortisiliquum
seeds. It was found that ECTI (contortisiliquum
trypsin inhibitor) strongly inhibits bovine trypsin
and chymotrypsin and also some serine
proteinases involved in the blood clotting cascade
and fibrinogen proteolysis: human plasma
kallikrein, factor XIIa and plasmin. ECTI showed
no inhibitory activity on factor Xa, thrombin or
tissue kallikrein or as on cysteine proteinases
such as papain and bromelain. ECTI didn't affect
thrombin time (TT) or prothrombin time (PT) but
increased activated partial thrombin time (APTT)
[17].
3.3 Folk and traditional uses of genus
Enterolobium
The wide spreading canopy of a mature
Enterolobium makes it an ideal shade tree,
whether for livestock in pasture lands, for
perennial crops such as coffee, or in roadside and
urban plantings [26]. Enterolobium cyclocarpum
has been proposed as an alternative for
rehabilitation of marginal soils, due to its ability
to form a symbiotic association with nitrogen-
fixing soil microorganisms [27]. Fruits and leaves
are used as forage allowing cattle to feed directly
from the tree or as a nutritional complement in
combination with the fodder [28]. The wood E.
cyclocarpum is resistant to attack by dry-wood
termites, which makes it feasible to be used in
house construction. It is also used as firewood
due to its high caloric content.
Enterolobium wood may also be used for
boat-building because of its durability in water; it
Mariam I. Gamal El-Din, et al. Arch Pharm Sci 1(1): 16-25
24
has been used in the past for water-troughs and
dug-out canoes. Mature fruits contain a gummy-
resinous juice which along with their own
smashed pulp is used to produce charcoal [29].
Seeds of E. cyclocarpum are rich in protein (up to
35%), and its amino acid composition is
comparable to that of wheat or fish flour. Seeds
also contain iron, calcium, phosphorus and
ascorbic acid. In some places, they are consumed
in sauces, soups and as a coffee substitute, and
several medicinal properties have been attributed
to them [30]. The root decoction of E. saman is
used in hot baths for stomach cancer in
Venezuela. Rain Tree is a traditional remedy for
colds, diarrhea, headache, intestinal ailments, and
stomachache. The leaf infusion is used as a
laxative In the West Indies; seeds are chewed for
a sore throat. The alcoholic extract of the leaves
inhibits Mycobacterium tuberculosis. In
Colombia, the fruit decoction is used as a
sedative [31]. Besides the traditional uses, several
biotechnological applications have been proposed
for this tree, such as the use of its gum as a fungi
culture substrate or for the production of ice
cream and yogurt [32].
4. CONCLUSION AND RECOMMENDATIONS
The plants of the genus Enterolobium have long
been used in folk medicine for the treatment of
different pathological conditions. In recent years, the
scientific interest in plants of Enterolobium genus has
increased greatly. Substantial progress on chemistry
and pharmacological properties of this genus has
shown it. Some species showed antimicrobial, anti-
inflammatory, antifungal, and anticancer activities.
Pharmacological studies have confirmed some uses in
folk medicine. Triterpenes and phenolic compounds
are of particular interest as many are highly potent
bioactive and perhaps responsible for most of the
activities shown by the plants of this genus.
A detailed study is recommended to understand the
structure-activity relationship of these constituents.
Many plant extracts of Enterolobium showed
biological activity. However, the particular constituent
responsible for the activity has not always been
isolated in the further process. Furthermore, some
plant extracts were only preliminary studied for their
in vitro activities, so, the advanced clinical trial of
them deserves to be further investigated.
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... Enterolobium is represented by 13 species characterized by bush or tree habit, bipinnate leaves, and auriculate and blackish fruits. These plants are typical of tropical and Neotropical regions with warm and temperate climates in the Americas (Lewis et al., 2005;El-Din et al., 2017;Silveira et al., 2017;Luz et al., 2021). ...
Article
Enterolobium contortisiliquum (Vell.) Morong (Fabaceae) is a plant widely distributed in several regions of Brazil, occurring in the phytogeographic domains of Atlantic Forest, Cerrado, and Caatinga. Cases of serious poisoning in cattle, goats, and sheep in the country caused by the ingestion of beans of this species have been reported by several studies. The present work aimed to carry out a systematic review of cases of poisoning by E. contortisiliquum in ruminants and list the main chemical compounds isolated from this plant. For this, searches were performed in the Google Academic, PubMed®, ScienceDirect®, and SciELO databases. A total of 26 articles published in the last 20 years (2001-2021) were included. Studies on cases of natural and experimental poisoning indicate that this species mainly causes photosensitization, abortions, digestive problems, and acute ruminal lactic acidosis in animals that ingest the pods of the plant. The main chemical compounds that occur in the species belong to the triterpene saponins, monoterpene, phenylpropene, and triterpene classes. It is likely that triterpene saponins isolated from E. contortisiliquum are associated with reported cases of photosensitization in cattle. New studies must be conducted to assess the mechanisms of action of chemical compounds isolated from this species in in vivo systems.
... Little attention has been paid to species-specific life history traits and their relevance under stress, particularly salinity. In this study, Enterolobium, a nitrogen (N 2 )-fixing legume from inland dry forests (El-Din et al. 2017), maintained relatively good growth up to 40 % seawater, beyond which growth strongly decreased, possibly indicating adverse effects of high soil salinity on the N 2 -fixing bacteria (Rhizobium). The importance of effective N 2 -fixing bacteria associations among plant species has been highlighted by Hanin et al. (2016), suggesting that salt-tolerant Rhizobium strains might significantly help plants cope with increased soil salinity. ...
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Three outbreaks of hepatogenous photosensitization caused by pods of Enterolobium contortisiliquum are reported in cattle. Clinical signs were anorexia, depression, photosensitization and abortion. Most affected cattle recovered in 30-40 d. At necropsies, liver was present, the gallbladder was enlarged and edematous, and numerous seeds of E contortisiliquum were in the forestomachs and abomasum. Fruits of the plants administrated to 2 calves produced clinical signs and 2/4 died. Clinical chemistry, gross necropsies and histopathology confirmed gastrointestinal irritation and liver degeneration. One calf dosed with on E contortisiliquum leaves did not develop clinical signs.
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Enterolobium cyclocarpum (Mimosaceae), a specie located in Venezuela, produces gum with very interesting physicochemical characteristics and high yield. The functionality of this gum as additive in the preparation of low fat yogurt was tested. Five treatments were applied, e.i. control treatment and the other ones with different gum concentration (0.05, 0.10, 0.15, 0.20%). Physico-chemical characteristics (fat, not fat solids, lactic acidity, viscosity, syneresis) and sensory properties were researched. Statistical analysis (ANOVA) of the results was applied. The product found with the highest gum concentration (0.20%) differs statistically (P<0.05) from those obtained with lower gum concentrations and with the control treatment (without gum). The gum tested (0.20%) provided a suitable viscosity for the yogurt, with corresponding low syneresis phenomenon and good texture. In addition, the product exhibited better sensory attributes, and exhibited the highest score for appearence (6.98), flavor (7.12), texture (7.18) and acceptability (7.48). These results showed good functionality for Enterolobium cyclocarpum gum in the preparation of low fat yogurt.
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Enterolobium contortisiliquum (Vell.) Morong is a tree belonging to family Leguminosae. Nevertheless, it is widely spread in Egypt; the chemical composition was not yet investigated. GC-MS analysis of unsaponifiable matter of E. contortisiliquum revealed that α- and β-amyrin and 4-methyl 2,6-di-tert-butylphenol to be its main components, while palmitic and 9,12-octadecadienoic acids were the major fatty acids. Nine sugar components were identified in hydrolysate of mucilage with glucose (34.89%), xylose (6.78%) and rhamnose (5.98%) being the predominant sugars by GLC. Fourteen amino acids have been identified in protein fraction. The phenolic fraction was chromatographed over polyamide to yield gallic acid, protocatechuic acid, quercetin-7-rutinoside, catechin, isovitexin and quercetin, which were characterized by the comparison of their physical and spectral data with those in the literature. Further, HPLC analysis of the phenolic fraction revealed the presence of pyrogallol, syringic and p-coumaric acids. The crude extract (70% alcohol) and the saponin fraction exhibited potent cytotoxic activity on HepG2 (IC50 14 and 29 µg/mL) and MCF7 (IC50 16 & 31 µg/mL) cell lines. The mucilage and petroleum ether fractions showed cytotoxicity activity on HepG2 with (IC50 19 & 61 µg/mL), while phenolic fraction showed cytotoxicity towards MCF7 cells with IC50 value of 79 µg/mL. The antibacterial activity of different fractions were evaluated against seven Gram-positive and six Gram-negative microorganisms using agar well diffusion assay method. Maximum inhibition was observed with compounds at 1 mg/mL; catechin and protocatechuic acid against Pseudomonas aeruginosa (-ve) (14.5 and 17 mm, respectively) while, the crude and petroleum ether extracts showed antimicrobial activity against Micrococcus luteus (+ve) (inhibition zone 12 and 10 mm, respectively). Whereas, polysaccharide and protein exhibited antimicrobial activity against Klebsiella pneumonia (-ve) (16 and 13 mm, respectively).
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Enterolobium cyclocarpum (Jacq.) Griseb. is a tropical tree that has folkloric implications against many ailments and diseases including cancer. To explore the ethnopharmacological claims against cancer, the cytotoxicity of the methanolic extract of the leaves, was investigated using the brine shrimp lethality assay, MTT assay using cervical (HeLa) and breast (MCF7) cancer cell lines, cell cycle analysis and Annexin V-FITC/PI assay. In the brine shrimp lethality assay, the extract showed cytotoxic activity with LC50 value of 31.63µg/ml. Significant growth inhibition was observed in both cell lines with IC50 values of 2.07±1.30µg/mL and 11.84±1.18µg/mL for HeLa and MCF7 respectively. Cell cycle analysis indicated that HeLa cells were arrested in the G2/M phase while MCF7 cells arrested in the G1/G0 phase. The Annexin V-FITC/PI assay revealed phosphatidylserine translocation in both cell lines and thus apoptosis induction upon treatment with the extract. The study demonstrated the potential antiproliferative activity of E. cyclocarpum thereby supporting the traditional claim and provides basis for further mechanistic studies and isolation of active constituents. Copyright © 2014. Published by Elsevier Ireland Ltd.
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The triterpenes 3β-hydroxy-21β-E-cinnamoyloxyolean-12-en-20-oic acid, 3β,21β-dihydroxyolean-12-en-28-oic acid (machaerinic acid) and its lactone (3β-hydroxyolean-12-en-21β→28-lactone) were isolated from the fruits of Enterolobium contorstisiliquum. Methyl and ethyl esters of 3β,21β-dihydroxyolean-12-en-oic acid were isolated and characterized as artifacts. The structures of these triterpenes have been established by a study of their chemical and spectroscopic (IR, MS and NMR) data.
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Crude cyclohexane and ethanol extracts from D. granadillo as well as ethanol extracts from E. cyclocarpum proved inhibitive to fungal growth. Purification of the cyclohexane extract from D. granadillo, using silica-gel column chromatography, revealed even higher anti fungal activity for the second fraction.
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The value of the tropical browse legumes Acacia cornigera (ACA), Albizia lebbekoides (ALB), Enterolobium cyclocarpum (ENT) and Leucaena leucocephala (LEU) as ruminal N sources was examined. The N content (g/kg dry matter) was 38.0, 28.6, 35.1 and 46.7, and acid detergent insoluble N (ADIN; g/kg dry matter) was 9.0, 10.7, 18.7 and 19.8 for ACA, ALB, ENT and LEU, respectively. In vitro gas production at 24 h ranked ACA > ENT > LEU > ALB (P < 0.001), except that there were no differences between ENT and LEU after 12 h of incubation. The N degradability was estimated by the in vitro relationship between gas production and ammonia N concentration (NDg), N disappearance from incubation residue (NDd), and incubation with Streptomyces griseus enzymes (NDe). To determine NDg, legume samples (601 ± 0.54 mg) were incubated with 0 mg (n = 3), 150 mg (n = 2) or 300 mg (n = 2) starch for 24 h in two experiments. Regression of ammonia (y, mg) on gas produced (x, ml) for each browse in each experiment (n = 7) yielded r2 coefficients between 0.974 and 0.997. Average estimated NDg were 0.32, 0.22, 0.63 and 0.22 for ACA, ALB, ENT and LEU, whereas NDd had N digestion coefficients of 0.40, 0.17, 0.70 and 0.36, and NDe 0.41, 0.24, 0.44 and 0.36, respectively. NDg was lower than NDd and NDe for LEU, but higher than NDe for ENT (P < 0.05). However, methods correlation ranged from 0.73 to 0.92. In vitro estimated N digestion suggested that 0.52, 0.17, 0.30 and 0.41 of undegraded N from ACA, ALB, ENT and LEU was intestinally digestible.