Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5442_Библиотеки_им_академика_М_И_Перельмана.pdf
Google Scholar and Pubmed) were consulted by using specific keywords such as “plant”
and “diarrhea,” combined with countries’ names from the lower Mekong basin:
“Thailand” or “Lao PDR” or “Vietnam” or “Cambodia.” Libraries from France, Cambodia,
and Lao PDR were also consulted to gather books, thesis, and reports by focusing on eth-
nobotanical data from Southeast Asia.
From these documents, information on plant species names, botanical tissues, therapeu-
tic indications, and countries of origin were extracted. All botanical names (genus and spe-
cies) were checked on The Plant List website (
http://www.theplantlist.org/).
A score was then calculated to rank the plant species by order of ethnobotanical impor-
tance, and thus generated a list of the most frequently used plants in the area. For each
plant species, citation frequency (number of bibliographic references citing the plant spe-
cies) and citation distribution (number of countries where the plant was reported to be
used) were obtained, and these two categories were multiplied to give a score. Only plants
with the highest score were considered in the discussion below.
Overview of the dataset
Overall, 431 plant species belonging to 307 botanical genera and 101 botanical families
were identified from 51 bibliographic referen ces. Among the latter, 35 references were
original ethnobotanical surveys, while 16 were review articles or documents presenting
anecdotal ethnomedical uses. Twenty-three documents reported ethnobotanical uses from
Thailand, 14 from Lao PDR, 12 from Cambodia, and 11 from Vietnam.
Of the 431 plant species reported, the most represented botanical families were
Fabaceae (48 plant species, 11.1%), Zingiberaceae (18, 4.2%), Rubiaceae (16, 3.7%),
Asteraceae (15, 3.5%), and Malvaceae (14, 3.2%). Terminalia was the most represe nted
botanical genus with seven plant species (1.6%), followed by Bauhinia, Calamus,andFicus
with five plant species each (1.2%), and Alpinia, Amomum, Dillenia, Dioscorea, Euphorbia,
Lagerstroemia, Melastoma, Rubus, Smilax, Syzygium, Zingiber, and Ziziphus with four plant
species each (0.9%). The most represented plant tissues were root (148 plant species,
34.3%), bark (124, 28.7%), leaf (118, 27.3%), stem (58, 13.4%), and fruit (54, 12.5%).
Regarding ethnobotanical uses, diarrhea and dysentery were mentioned for 351 and 185
plant species respectively. A total of 20 plants were mentioned for treating diarrhea and
vomiting (e.g., Psidium guajava L., Chromolaena odorata (L.) R.M.King & H.Rob., and Careya
arborea Roxb.), 11 for diarrhea in children (e.g., P. guajava, Oroxylum indicum (L.) Kurz, and
Saccharum officinarum L.), and 9 for cholera (e.g., Holarrhena pubescens Wall. ex G.Don).
Only 6 plant species (i.e., P. guajava, C. odorata, Alstonia scholaris (L.) R. Br., Centella asiatica
(L.) Urb., Allium sativum L., Caesalpinia sappan L.) were used in the four countries from the
lower Mekong area, 10 species (i.e., Punica granatum L., Mangifera indica L., H. pubescens, O.
indicum, Piper nigrum L., Coscinium fenestratum (Goetgh.) Colebr., Rhodomyrtus tomentosa
(Aiton) Hassk., Cyperus rotundus L., Ageratum conyzoides (L.) L., and Curcuma aromatica
Salisb.) were used in three different countries, 49 were used in two countries, and 366 plant
species were used in only one country from the lower Mekong basin. Of the 431 plant spe-
cies, 203 (47.1%) plant species were reported in Cambodia for the treatment of diarrheal ill-
nesses, 113 (26.2%) in Thailand, 112 (26.0%) in Vietnam, and 75 (17.4%) in Lao PDR.
The top 24 plant species with the highest score are shown in
Table 7.1
244 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
TABLE 7.1 Most used plant species for diarrheal illnesses in the lower Mekong basin.
Plant species Botanical family
Geographical
distribution Tissue Ethnomedical uses Countries and ethnic groups
a
Citation
distribution
b
Citation
frequency
c
Score
d
Psidium guajava L. Myrtaceae Five
continents
(native to
Central and
South
America)
Bark, bud,
fruit, leaf, leaf
(young), stem,
root, trunk,
wood
Diarrhea, diarrhea
(infant), diarrhea
(mucus), diarrhea
(vomiting),
dysentery
Cambodia (Bunong, Khmer), Lao
PDR, (Brou, Hmong, Kry, Saek),
Thailand (Karen, Lahu, Lisu,
other, Thai Yuan, Yao), Vietnam
41560
Chromolaena odorata
(L.) R.M.King & H.
Rob.
Asteraceae Five
continents
(native to
America)
Leaf, leaf
(young), root
Diarrhea, diarrhea
(vomiting),
dysentery
Cambodia (Bunong), Lao PDR
(Brou, Hmong, Kry, Saek),
Thailand (Karen), Vietnam (Van
Kieu, other)
4832
Alstonia scholaris
(L.) R. Br.
Apocynaceae Asia,
Australia
Bark, leaf,
stem bark
Diarrhea, dysentery Cambodia, Lao PDR, Thailand,
Vietnam
4728
Allium sativum L. Amaryllidaceae Five
continents
(native to
Central Asia)
Bulb Diarrhea, dysentery Cambodia, Lao PDR, Thailand,
Vietnam
4624
Centella asiatica (L.)
Urb.
Apiaceae Five
continents
(native to
Africa, Asia
and Oceania)
Leaf, whole
plant
Diarrhea, dysentery Cambodia, Lao PDR (Kry),
Thailand (Karen, Lahu), Vietnam
4624
Punica granatum L. Lythraceae Five
continents
(native to
Central Asia)
Flower, fruit
(pericarp),
leaf, leaf
(young), root
Diarrhea, dysentery Cambodia, Thailand (Karen,
other), Vietnam
3721
Caesalpinia sappan L. Fabaceae Southeast
Asia
Bark, leaf,
root, stem
wood
Diarrhea, dysentery Cambodia, Lao PDR, Thailand
(Karen, Yao), Vietnam
4520
Mangifera indica L. Anacardiaceae Five
continents
(native to
South Asia)
Bark, root,
seed
Diarrhea, dysentery Cambodia (Bunong, Khmer),
Thailand (Lahu, Lisu), Vietnam
(Van Kieu)
3618
(Continued)
TABLE 7.1 (Continued)
Plant species Botanical family
Geographical
distribution Tissue Ethnomedical uses Countries and ethnic groups
a
Citation
distribution
b
Citation
frequency
c
Score
d
Holarrhena pubescens
Wall. ex G.Don
Apocynaceae Asia, Africa Bark, root,
stem
Cholera, diarrhea,
dysentery
Cambodia, Lao PDR, Thailand
(Tai Yai)
3618
Oroxylum indicum
(L.) Kurz
Bignoniaceae Asia Bark, root Diarrhea, diarrhea
(infant), dysentery
Cambodia, Lao PDR (Brou,
Saek), Vietnam
3515
Piper nigrum L. Piperaceae Africa,
America, Asia
(native to
South India)
Fruit Diarrhea, dysentery Cambodia, Thailand, Vietnam 3 5 15
Careya arborea Roxb. Lecythidaceae Asia Bark, leaf, leaf
(young), root,
stem, trunk
Diarrhea, diarrhea
(mucus), diarrhea
(simple), diarrhea
(vomiting),
dysentery
Cambodia (Bunong, Khmer),
Vietnam
2612
Coscinium
fenestratum
(Goetgh.) Colebr.
Menispermaceae Asia Liana, root,
stem
Diarrhea, dysentery Cambodia, Lao PDR (Brou, Kry),
Vietnam
3412
Rhodomyrtus
tomentosa (Aiton)
Hassk.
Myrtaceae America, Asia
(native to
South Asia)
Fruit, leaf,
root, stem,
wood
Diarrhea, dysentery Cambodia (Bunong), Thailand,
Vietnam
3412
Cyperus rotundus L. Cyperaceae Five
continents
(native to
Africa, Asia,
and Europe)
Root Diarrhea, dysentery Lao PDR, Thailand, Vietnam 3 4 12
Cratoxylum
formosum (Jacq.)
Benth. & Hook.f. ex
Dyer
Hypericaceae Southeast
Asia
Bark, leaf,
root, stem,
trunk
Diarrhea (mucus),
diarrhea
(vomiting),
dysentery
Cambodia (Bunong), Thailand
(Lahu, Lawa)
2510
Eurycoma longifolia
Jack
Simaroubaceae Southeast
Asia
Bark, fruit,
leaf, root
Diarrhea, dysentery Cambodia, Vietnam 2 5 10
Ageratum conyzoides
(L.) L.
Asteraceae Five
continents
(native to
Central
America)
Leaf, root Diarrhea, dysentery Cambodia (Bunong), Lao PDR
(Brou), Vietnam
339
Curcuma aromatica
Salisb.
Zingiberaceae Asia Rhizome Diarrhea, diarrhea
bloating, diarrhea
piles
Cambodia, Lao PDR, Thailand 3 3 9
Musa 3 paradisiaca
L.
Musaceae Five
continents
(native to
Malaysia)
Flower, fruit,
trunk (young)
Diarrhea, dysentery Cambodia (Bunong, Khmer),
Thailand (Karen, Yuan)
248
Zingiber officinale
Roscoe
Zingiberaceae Five
continents
(native to
India)
Rhizome Diarrhea Cambodia (Bunong), Thailand
(Karen, Other)
248
Areca catechu L. Arecaceae Africa, Asia
(native to
Philippines)
Leaf, fruit,
root, seed
Diarrhea, dysentery Cambodia, Vietnam 2 4 8
Shorea obtusa Wall.
ex Blume
Dipterocarpaceae Southeast
Asia
Bark, root, sap,
stem, trunk,
wood
Diarrhea, diarrhea
(mucus)
Cambodia (Bunong), Thailand
(Tai Yai)
248
Xylia xylocarpa
(Roxb.) Taub.
Fabaceae Africa, Asia
(native to
South Asia)
Bark, fruit,
root, stem,
trunk, wood
Diarrhea (mucus),
diarrhea
(vomiting),
dysentery
Cambodia (Bunong), Thailand
(Yuan)
248
a
Countries and ethnic groups in which the plant species were reported to be used. When the ethnic group was not mentioned in the reference, the term “other” was employed.
b
Number of countries reporting the plant in the treatment of diarrhea illnesses.
c
Number of bibliographic references reporting the plant in the treatment of diarrheal illnesses.
d
Calculated by multiplying “citation frequency” and “citation distribution” numbers.
Of these 24 plant species, four are endemic to Southeast Asia (C. sappan L., Cratoxylum
formosum (Jacq.) Benth. & Hook.f. ex Dyer; Eurycoma longifolia Jack; Shorea obtusa Wall. ex
Blume), 21 are native to Asia and 10 are distributed throughout the five continents. The
following section focuses on the first 10 most represented plant species.
Discussion of some selected plant species
Psidium guajava
Psidium guajava (Myrtaceae) (Fig. 7.3), also known as guava tree, is a shrub or small tree
native to Central and South America, and widely cultivated throughout the world (Sitther
et al., 2014
). According to the bibliographic review, a total of 13 ethnic groups distributed
throughout the four countries from the lower Mekong area mentioned the use of guava for
the treatment of diarrheal illnesses. Various parts of the tree were reported to be used as
antidiarrheic, with leaves and bark being the most used ones. Also, guava tree was men-
tioned for the treatment of different diarrheal illnesses such as simple diarrhea, infant diar-
rhea, diarrhea with mucus, diarrhea with vomiting, and dysentery. P. guajava was already
reported to be used for diarrheal illnesses in other countries such as Brazil, China, Congo,
Fiji, Mexico, Mozambique, Peru, Philippines, Senegal, South Africa, Trinidad, and USA
(
Gutie
´
rrez, Mitchell, & Solis, 2008). From a pharmacological perspective, a wide range of
in vitro and in vivo assays validated the use of P. guajava for infectious diarrhea. Its in vitro
antibacterial activity was confirmed using a hot aqueous extract of dried leaves of P. guajava
on S. flexneri and V. cholerae. The same extract also demonstrated an antiadherence effect on
FIGURE 7.3 Photographs of the three most used antidiarrheal plant species from the lower Mekong basin: (A)
Psidium guajava; (B) Chromolaena odorata; (C) Alstonia scholaris.
248 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
EPEC and an antiinvasive effect on both EIEC and S. flexneri, and finally decreased the pro-
duction of E. coli heat-labile toxin and cholera toxin (
Birdi et al., 2010). Antirotavirus activity
was also evaluated with a methanolic extract of P. guajava leaves which showed activity
against a simian rotavirus (SA-11) at a concentration of 8 μg/mL (
Gonc¸alves et al., 2005).
Regarding in vivo studies, P. guajava leaf extract (300 mg/kg per day) showed quicker clear-
ance of infection after 19 days in an infectious diarrhea model using Citrobacter rodentium-
infected mice (
Gupta & Birdi, 2015). In another in vivo model using S. flexneri-infected rats,
P. guajava leaf extract at 200 mg/kg reduced the number and weight of stools collected, and
the density of S. flexneri after 5 days of treatment (
Hirudkar et al., 2020a, 2020b). Similar
results were obtained in another study performed by the same authors in an EPEC-induced
diarrhea rat model (
Hirudkar et al., 2020). Clinical trials have also been performed to con-
firm the antidiarrheal effect of guava tree. In Mexico, a phytodrug containing guava leaves
administered every 8 h during 3 days to 50 patients with acute diarrheic disease signifi-
cantly reduced the duration of abdominal pain in these patients (
Lozoya et al., 2002). In
India, an oral guava leaf decoction administered to 109 patients suffering from acute diar-
rhea significantly decreased stool frequency after 24 h and reduced the intensity of abdomi-
nal pain after 48 h (
Birdi, Krishnan, Kataria, Gholkar, & Daswani, 2020). All these studies
demonstrate that P. guajava is of great interest in the treatment of diarrheal illnesses. Some
bioactive compounds (e.g., quercetin and quercetin derivatives) have been isolated, but
none of them seem to be solely responsible for the antidiarrheal effect observed (
Birdi et al.,
2010
). Thus the development of guava-based phytomedicines should be encouraged, and
then be added to the therapeutics used in the management of infectious diarrhea.
Chromolaena odorata
Chromolaena odorata (Asteraceae) (Fig. 7.3) is a small herbaceous plant native to the
Americas and is considered one of the worst terrestrial invasive species in the Old World
tropics (
Yu, He, Zhao, & Li, 2014). In the literature review, C. odorata was cited as antidiar-
rheal agents by eight ethnic groups from the lower Mekong basin. Leaf and root of the
plant are used for treating simple diarrhea, diarrhea with vomiting, and dysentery. C.
odorata is also used for treating diarrheal illnesses in Bangladesh and Nigeria (
Aba et al.,
2015; Jahan et al., 2019
). Antidiarrheal effect (reduction in number of feces) of a methanolic
extract of C. odorata leaves at 50, 100, and 200 mg/kg was demonstrated on a castor oil-
induced diarrhea in mice. In the same study, the extract significantly reduced the intestinal
motility in mice at the same concentrations (
Taiwo, Olajide, Soyannwo, & Makinde, 2000).
The antidiarrheal activity (reduction in the frequency and wetness of stools) of C. odorata
was later conf irmed in a rat model of castor oil-induced diarrhea using an ethanolic leaf
extract of C. odorata at 200 and 400 mg/kg (
Aba et al., 2015). A dichloromethane extract of
C. odorata demonstrated antibacterial activity against V. cholerae with a MIC value of
156 μg/mL. Two flavonoid compounds (i.e., scutellarein tetramethyl ether, sinensetin)
were identified as being responsible for this antibacterial activity (
Atindehou et al., 2013 ).
Despite its efficacy, the use of C. odorata is controversial due to the presence of pyrrolizi-
dine alkaloids which exhibit hepatotoxicity and carcinogenicity (
Anyanwu et al., 2017 ).
Therefore more research is needed to investigate the dosage range that is safe for humans
(
Omokhua, McGaw, Finnie, & Van Staden, 2016).
249Discussion of some selected plant species
Medicinal Plants as Anti-infectives
Alstonia scholaris
Alstonia scholaris (Apocynaceae) (Fig. 7.3) is a tree native to tropical and subtropical
Asia and North Australia (Pandey et al., 2020). In the literatu re analysis, a total of seven
references reported the use of A. scholaris as antidiarrheal and antidysenteric agents all
over the four countries of the lower Mekong basin. Bark and leaf were the two most cited
plant tissues. Other studies from India, Indonesia, Papua New Guinea, and the
Philippines also reported the use of A. scholaris for treating diarrheal illnesses (
Khyade
et al., 2014
). Regarding its pharmacological properties, a methanolic extract of A. scholaris
showed antidiarrheal effect (reduction in the frequency of defecation) in the castor-oil
induced diarrhea in mice model and its spasmolytic activity was confirmed using an iso-
lated rabbit jejunum preparation (
Shah et al., 2010). The methanolic extract was also stud-
ied for its acute and sub-acute toxicity, and showed liver damage (slight degeneration and
centrilobular necrosis) after 28 days at 500 and 1000 mg/kg but no toxicity was observed
after 14 days (
Bello et al., 2016). It was previously noted that the subacute toxicity might
be due to the presence of echitamine (
Baliga et al., 2004). Moreover, teratogenic effect was
also observed in mice using a hydroalcoholic extract of A. scholaris at doses above 240 mg/
kg (
Jagetia and Baliga, 2003). Therefore, the long-term use of A. scholaris should be
avoided, and more studies should be performed to evaluate its safety in humans.
Allium sativum
Allium sativum (Amaryllidaceae) is a bulb crop native to Central Asia that has been cul-
tivated all over the world for thousands of years. In the lower Mekong region, the bulb
was reported to be used for treating diarrhea and dysentery in Cambodia, Lao PDR,
Thailand, and Vietnam. In Palestine, the raw bulb is mixed with yogurt then eaten thrice a
day to treat diarrhea (
Jaradat, Ayesh, & Anderson, 2016). The bulb of A. sativum was also
cited as an antidysenteric agent in Mexico (
Alanı
´
s et al., 2005). Most of the studies validat-
ing the use of garlic in the treatment of diarrhea have focused on its antiinfective proper-
ties, especially its antibacterial and antiprotozoal activities. A methanolic extract of A.
sativum was tested on E. coli, Salmonella sp., S. flexneri, and S. sonnei, but failed to inhibit
their growth at 8 mg/mL using the agar dilution method (
Alanı
´
s et al., 2005). In another
study, a garlic concentrate along with its organosulfur compounds demonstrate a bacteri-
cidal activity on C. jejuni. This activity was due to cell membrane damages (
Lu et al.,
2011
). Its antibacterial activity was also confirmed on Salmonella typhi using in vitro and
in vivo assays. In the latter experiment, the consumption of garlic extract in infected mice
caused a significant reduction in S. typhi load in the feces and reduced the duration of
infection (
Adebolu, Adeoye, & Oyetayo, 2011). Other studies focused on its antiprotozoal
activity. A methanolic extract of A. sativum showed moderate in vitro antiprotozoal activ-
ity against E. histolytica (IC
50
5 61.8 μg/mL) and G. lamblia (IC
50
5 64.9 μg/mL) (Calzada,
Ye
´
pez-Mulia, & Aguilar, 2006
). In another study, some compounds (i.e., allyl alcohol, allyl
mercaptan) were identified as being responsible for the antiprotozoal activity against
Giardia intestinalis (
Harris, Plummer, Turner, & Lloyd, 2000). Also, an aqueous extract of
garlic was administered to mice infected with Blastocystis spp. at 20 mg/kg per day and
showed a reduction in shedding of cysts (
Abdel-Hafeez, Ahmad, Kamal, Abdellatif, &
250 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
Abdelgelil, 2015). Garlic also presents some adverse effects and can induce contact derma-
titis along with bleeding events. This explains why garlic should not be used by patients
using anticoagulant therapy (
Kuete, 2017). Besides the numerous studies aiming to eva lu-
ate its antiinfective properties, there is a lack of studies validating its use for diarrhea.
Therefore more effort should be done to confirm its antidiarrheal potential.
Centella asiatica
Centella asiatica (Apiaceae) is a small herbaceous plant species native to Asia, Africa,
and Oceania and widely distributed throughout the five continents. According to the liter-
ature review, its leaf and the whole plant have been used for treating diarrhea and dysen-
tery in Cambodia, Lao PDR, Thailand, and Vietnam. In India, the whole plant is ground to
extract the juice which is used orally to relieve diarrhea and dysentery (
Laloo &
Hemalatha, 2011
). The antibacterial activity of a dichloromethane/methanol extract (1:1,
vol./vol.) was tested on bacteria responsible for diarrhea such as E. coli, S. typhi, and S.
sonnei, but the very high MIC values found (MIC . 50 mg/mL) did not confirm its activity
(
Sieberi, Omwenga, Wambua, Samoei, & Ngugi, 2020). While C. asiatica is widely studied,
especially for its neuroprotective activity, antidiabetic effect, or wound healing activity, its
effect on diarrhea has been poorly investigated (
Sun et al., 2020). Thus further pharmaco-
logical studies should be performed to validate the use of C. asiatica for diarrheal illnesses.
Punica granatum
Punica granatum (Lythraceae), also known as pomegranate, is a shrub native to Central Asia
and now cultivated in most regions of the five continents (
Shaygannia, Bahmani, Zamanzad, &
Rafieian-Kopaei, 2015
). Regarding its use in the lower Mekong region, the flower, fruit, leaf,
and root of P. granatum were mentioned for treating diarrheal illnesses (i.e., diarrhea and dys-
entery) in Cambodia, Thailand, and Vietnam. Pomegranate was also reported to be used for
diarrheal illnesses in Algeria, China, Iran, Mexico, Pakistan, and Turkey (
Bouasla & Bouasla,
2017; Ghorbani, 2005; Lee, Xiao, & Pei, 2008; Navarro, Villarreal, Rojas, & Lozoya, 1996; Rashid
et al., 2015; Rose, O
¨
zu
¨
nel, & Bennett, 2013
). The effect of an aqueous extract of P. granatum peel
at 100, 200, 300, and 400 mg/kg was evaluated for its antisecretory, antimotility, and antidiar-
rheal activities using the enteropooling assay in isolated rat ileum, the charcoal meal test in
rats, and the castor oil-induced diarrhea in rats, respectively. The results revealed that P. grana-
tum reduced diarrhea in a dose-dependent manner by inhibiting intestinal motility and fluid
accumulation (
Qnais, Elokda, Ghalyun, & Abdulla, 2007). Another study confirmed the antidi-
arrheal activity of pomegranate, by testing a methanolic extract of P. granatum fruitat800mg/
kg on a castor oil-induced diarrhea rat model (
Souli et al., 2015). Punicalagin, corilagin, and
ellagic acid were identified as responsible for the antidiarrheal effect of anethylacetatefraction
of P. granatum peels (
Zhao et al., 2018). Regarding its antimicrobial effect, a methanolic extract
of P. granatum dried fruit peel showed a significant antibacterial activity against a multidrug-
resistant S. typhi with a MIC value of 32 μg/mL (
Rani & Khullar, 2004). A mouse Salmonella
typhimurium infection model was used to study the in vivo antibacterial activity of an ethanolic
extract of P. granatum peel and resulted in significant reduction of mouse mortality after
251Discussion of some selected plant species
Medicinal Plants as Anti-infectives
6 days. In the extract used, the major compounds were gallic acid, ellagic acid, and punicalagin
(
Choi et al., 2011). Also, an aqueous extract of P. granatum leaf was tested on human (HCR3)
and simian (SA-11) rotaviruses but did not show any inhibition activity (
Gonc¸alves et al.,
2005
). In a randomized controlled clinical trial, 62 patients with ulcerative colitis were treated
with an aqueous extract of pomegranate peel (6 g of dry peel per day) and resulted in a reduc-
tion of antidiarrheal medication need after 4 weeks (
Kamali et al., 2015). Overall, the effect of
P. granatum fruit has been validated by various pharmacological models which encourage the
development of pomegranate-based phytomedicines for treating diarrheal illnesses. However,
some concerns regarding its long-term toxicity have been raised and this should incite further
exploration of its safety (
Ismail, Sestili, & Akhtar, 2012).
Caesalpinia sappan
Caesalpinia sappan (Fabaceae) is a tree found in Southeast Asia and is mainly used as a
dyeing plant (
Nirmal, Rajput, Prasad, & Ahmad, 2015). According to the literature analy-
sis, the bark, leaf, root, and stem wood of C. sappan are used to treat diarrhea and dysen-
tery in the four countries from the lower Mekong region. Its antibacterial activity has been
widely studied using in vitro models. An ethanolic and an aqueous extract of C. sappan
exhibited good growth inhibition activity against S. typhi and E. coli using the disk diffu-
sion method (
Srinivasan et al., 2012). 5-Hydroxy-1,4-naphthoquinone isolated from C. sap-
pan heartwood showed growth inhibition activity on Clostridium perfringens, a bacteria
causing food poiso ning (
Lim, Jeon, Jeong, Lee, & Lee, 2007). Brazilin, another compound
from C. sappan, also showed growth inhibition on S. typhimurium (MIC 5 64 μg/mL) and
E. coli (MIC 5 256 μg/mL) (
Xu & Lee, 2004). Besides its antibacterial activity, no studies
have been yet performed to validate its full antidiarrheal potential, and thus a better inves-
tigation of its pharmacological activities is needed.
Mangifera indica
Mangifera indica (Anacardiaceae), commonly known as mango, is a tree native to Asia
and widely cultivated in tropical regions (
Ediriweera, Tennekoon, & Samarakoon, 2017). In
the lower Mekong area, the bark, root, and seed of M. indica are used for treating diarrhea
and dysentery in Cambodia, Thailand, and Vietnam. Other studies from Bangladesh,
Canary Islands, Guyana, India, Senegal, and Sri Lanka also reported the use of mango in
the treatment of diarrheal illnesses (
Ediriweera et al., 2017). Several in vivo studies were per-
formed on mango to test for its antidiarrheal effect. Two studies focused on the antidiarrheal
potential of mango seeds.
Sairam et al. (2003) demonstrated that a methanolic and an aque-
ous extract of M. indica seeds administered orally at 250 mg/kg to mice using a castor oil-
induced diarrhea model significantly reduced the number of feces excreted. In the same
study, the authors also showed a significant reduction in intestinal transit time with the
methanolic extract of M. indica seeds administered orally at 250 mg/kg (
Sairam et al., 2003).
Rajan, Suganya, Thirunalasundari, and Jeeva (2012) showed similar results by testing M.
indica seed kernels in a castor oil-induced diarrhea model and in a charcoal meal test (
Rajan
et al., 2012
). Another in vivo study focused on the antidiarrheal potential of mango stem
bark. In this work, Tchoumba Tchoumi et al. (2020) demonstrated an antidiarrheal (i.e.,
252 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
reduction in the frequency of stools), antisecretory, and antimotility effect of an aqueous
and a methanolic extract of M. indica stem bark by testing concentrations ranging from 300
to 500 mg/kg (
Tchoumba Tchoumi et al., 2020). In Yakubu and Salimon (2015),anaqueous
extract of M. indica leaves was tested at 25, 50, and 100 mg/kg using a castor oil-induced
diarrhea model, an enteropooling assay, and a charcoal meal test. In this work, M. indica
leaves reduced by half the total number of wet feces, reduced the mass and volume of intes-
tinal fluid, and reduced the intestinal motility in a dose-dependent manner (
Yakubu &
Salimon, 2015
). Not only various parts of M. indica have proven their antidiarrheal activity
but the plant has also demonstrated a good antibacterial activity against enteric pathogens.
For example, an organic extract of M. indica leaves has shown to inhibit the growth of S. flex-
neri with an MIC value of 250 μg/mL (
van Vuuren, Nkwanyana, & de Wet, 2015), and an
aqueous and an ethanolic extract of M. indica seeds have demonstrated an inhibition of
Shigella dysenteriae growth with MIC values of 380 and 190 μg/mL, respectively (
Rajan,
Thirunalasundari, & Jeeva, 2011
). Regarding in vivo studies, an aqueous and a methanolic
extract of M. indica stem bark at concentrations ranging from 300 to 500 mg/kg showed a
significant reduction of bacterial load in feces after 14 days using an EPEC-infected mice
model (
Tchoumba Tchoumi et al., 2020). Several compounds might be involved in the anti-
bacterial activity of M. indica including gallic acid, kaempferol, linalool, mangiferin, methyl
gallate, and quercetin (
Ediriweera et al., 2017). In a recent clinical trial, a mango juice by-
product comprising peel and pulp of mango significantly reduced the severity of diarrheal
events in children of 68 years old over a period of 2 months. This effect was attributed to
the presence of gallotannins (
Anaya-Loyola et al., 2020).Thesafetyofmangowasalsostud-
ied using a subchronic (28 days) toxicity assay, and it was shown that the aqueous extract of
M. indica leaves does not present genotoxic, clastogenic, and cytotoxic effect at doses of 150,
250, 500, and 1000 mg/kg (
Villas Boas et al., 2019). Overall, M. indica present a good safety
profile and multiple pharmacological actions which make it a good candidate for further
development as an antidiarrheal phytomedicine.
Holarrhena pubescens
Holarrhena pubescens (syn. H. antidysenterica (Roth) Wall. ex A.DC., Apocynaceae) is a
flowering plant native to southern Africa, India, Southeast Asia, and southern China
(
Zahara, Panda, Swain, & Luyten, 2020). In the literature analysis, H. pubescens was men-
tioned in six bibliographic references originating from Cambodia, Lao PDR, and Thailand.
In these countries, the bark, root, and stem of H. pubescens have been used for treating
cholera, diarrhea, and dysentery. This plant is also used in other parts of the world suc h
as India where the bark is used to treat dysentery (
Gairola, Sharma, Gaur, Siddiqi, &
Painuli, 2013
), and Pakistan where the beans are mixed with yogurt to treat diarrhea and
cramps (
Ahmad et al., 2018). The antidiarrheal activity of an ethanolic extract of H. pubes-
cens seeds was evaluated in rats using a castor oil-induced diarrhea model, and an oral
administration of this extract was shown to reduce the severity of diarrhea at 200 and
400 mg/kg. In the same study, this extract was administered orally to rats using an ETEC-
infected model, and it showed a reduction in body weight change comparable to the posi-
tive control gentamicin (
Sharma et al., 2015). Further investigation of the antibacterial
253Discussion of some selected plant species
Medicinal Plants as Anti-infectives