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234 6. Antibacterial activity of some selected medicinal plants of Pakistan
Medicinal Plants as Anti-infectives
CHAPTER
7
Medicinal plants used as antidiarrheal
agents in the lower Mekong basin
Franc¸ois Chassagne
UMR 152 PharmaDev, IRD, UPS, Universite
´
de Toulouse, Toulouse, France
Introduction
The Mekong is the 10th largest river in the world, it originates in the Tibetan Plateau and
runs through six different countries: China, Myanmar, Lao PDR, Thailand, Cambodia, and
Vietnam before emptying into the South China Sea (
Adamson, Rutherfurd, Peel, & Conlan,
2009
). The lower part of the Mekong, also known as the lower Mekong basin, flows from
Lao PDR to Vietnam, and is home to about 67 million people including more than 100 eth-
nic groups (
Laws & Semone, 2009; Mainuddin, Kirby, & Hoanh, 2011)(Fig. 7.1). This area is
also highly biodiverse with about 20,000 plant species, 430 mammals, 1200 bird species, 800
reptile and amphibian species, and 1148 fish species (
The Mekong River Commission, 2019).
This rich biodiversity is supporting by a large variety of landscapes with the highlands of
northern Thailand and northern Lao PDR, the Annamites mountains of eastern Lao PDR
and western Vietnam, the plains in Lao PDR, Thailand and Cambodia, and the Mekong
delta and costal mangroves (
Douglas, 2005). Different forest formations are encountered in
the area such as wet evergreen forests, semievergreen forests, mixed deciduous forests,
deciduous dipterocarp woodlands, montane forests, wetlands, and swamp forests (
Rundel,
2009
). This unique biodiversity provides a wide range of ecosystem services which benefit
human well-being and human health. It represents a significant source of food for rural and
indigenous communities living in the area, and it also plays an important role in health care
systems by providing medicinal resources such as medicinal plants (
Walther et al., 2016).
In the lower Mekong basin, diarrheal diseases are frequent and remain one of the leading
causes of morbidity and mortality, especially among children under five (
Fischer Walker,
Perin, Aryee, Boschi-Pinto, & Black, 2012; Troeger et al., 2016
). From 2010 to 2015, 147, 90,
and 27 diarrhea outbreaks have been reported in Cambodia, Lao PDR, and Vietnam, respec-
tively (
Lawpoolsri et al., 2018). Moreover, global change (i.e., climate change, rapid popula-
tion growth, industrialization, and intensive agricultural development) in the area affect
235
Medicinal Plants as Anti-infectives
DOI:
https://doi.org/10.1016/B978-0-323-90999-0.00015-X Copyright © 2022 Elsevier Inc. All rights reserved.
236 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
water quality and can increase the number of diarrheal events (Boithias et al., 2016; Chea,
Grenouillet, & Lek, 2016; McIver et al., 2014; Phung, Huang, Rutherford, Chu, Wang, &
Nguyen, 2015; Phung, Huang, Rutherford, Chu, Wang, Nguyen, ... Nguyen, 2015
).
The WHO defines diarrhea as the passage of three or more loose or liquid stools per
24 h, or more frequently than is normal for the individual (
WHO, 2020). Various clinical
manifestations of diarrhea have been described including acute ( , 7 days), prolonged
(713 days), persistent (1419 days), and chronic (1429 days) diarrhea (
Shane et al.,
2017
). Two main forms of acute diarrhea are recognized: acute watery diarrhea (includes
cholera), and acute bloody diarrhea, also called dysentery, which manifests as frequent
scant stools with blood and mucus (
Shane et al., 2017).
Acute diarrhea is mainly caused by bacteria and viruses and to a lesser extent by para-
sites (
Marcos & DuPont, 2007). In the lower Mekong basin, the main causative agents are
rotaviruses and diarrheagenic Escherichia coli strains including enterotoxigenic E. coli (ETEC),
enteroaggregative E. coli, enteropathogenic E. coli (EPEC), and enteroinvasive E. coli (EIEC)
(
Meng et al., 2011; Thompson et al., 2015; Vu Nguyen, Le Van, Le Huy, Nguyen Gia, &
Weintraub, 2006
). Other bacterial agents have also been reported in the area: Salmonella spp.,
Shigella spp., Vibrio cholerae,andCampylobacter jejuni/coli (
Mahapatra et al., 2014; Ngoc, 2017;
Phetsouvanh et al., 2008; Poramathikul et al., 2016; Von Seidlein et al., 2006
).
The first-line treatment of acute diarrhea is oral rehydration solution for all cases, while anti-
biotics are mostly used for severe cases of diarrhea, at-risk populations (e.g., child, elderly per-
son, immunocompromised patients), and traveler’s diarrhea (
Riddle, Dupont, & Connor, 2016).
However, these bacterial agents are becoming increasingly resistant to antibiotics, caus-
ing problems in the management of patients with infectious diarrhea. Antibiotic-resistant
bacteria include strains of Campylobacter, ETEC, Salmonella, Shigella, and V. cholerae in
Cambodia (
Meng et al., 2011; Poramathikul et al., 2016); strains of Campylobacter,
Salmonella, Shigella, and all types of E. coli in Vietnam (Thompson et al., 2015; Vu Nguyen
et al., 2006
); and strains of nontyphi Salmonella, Shigella, and V. cholerae in Lao PDR
(
Iwanaga et al., 2004; Phuong et al., 2017; Yamashiro et al., 1998).
Traditional medicine for diarrheal diseases in the Mekong Basin
The role of traditional medicine in the management of diarrhea
Traditional practices, especially medicinal plants, have been reported to treat diarrhea in
various continents including Africa, Europe, India, and South America (
Palombo, 2006). In the
lower Mekong region, they continue to play an important role in primary health care, espe-
cially for rural populations due to their availability, accessibility, low cost, and effectiveness
(
Maneenoon et al., 2015; Nguyen, Bun, Ollivier, & Dang, 2020). Sydara et al. (2005) inter-
viewed 592 villagers of the Champasak province in Lao PDR and found that 77% had already
L
FIGURE 7.1 Map showing the four countries from the lower Mekong basin. Source: From Adamson, P.T.,
Rutherfurd, I.D., Peel, M.C., & Conlan, I.A. (2009). The hydrology of the Mekong River. In: The Mekong (pp. 53-76).
Australia: Elsevier Inc. https://doi.org/10.1016/B978-0-12-374026-7.00004-8. Mekong River Commission. (2018). An intro-
duction to MRC procedural rules for Mekong water cooperation. Retrieved from
https://www.mrcmekong.org/assets/
Publications/MRC-procedures-EN-V.7-JUL-18.pdf. (Accessed December 2021).
237Traditional medicine for diarrheal diseases in the Mekong Basin
Medicinal Plants as Anti-infectives
used traditional medicine, and 59% had used traditional medicine in the last 6 months
(
Sydara et al., 2005). Among the interviewees using traditional medicine, almost all of them
reported using traditional medicine for treating diarrhea (
Sydara et al., 2005). In a Kho-Cil
community from the South of Vietnam (Lam Dong province), 79% of the 124 informants inter-
viewed reported to use medicinal plants for their health problems including diarrhea
(
Nguyen et al., 2020). In northern Thailand, Panyadee, Balslev, Wangpakapattanawong, and
Inta (2019) inventoried medicinal plants found in 195 home gardens from four villages and
showed that diarrhea was one of the most common ailment treated with these plants
(
Panyadee et al., 2019). In another study, Tangjitman, Wongsawad, Kamwong, Sukkho, and
Trisonthi (2015) studied the medicinal plants used by Karen people of northern Thailand for
digestive disorders and showed that diarrhea was associated with the highest number of plant
species and uses recorded (
Tangjitman et al., 2015). In a Vietnamese rural district, mothers
mentioned traditional herbs as being the most used therapies for treating diarrhea in children
under the age of five (
Le,Ottosson,Nguyen,Kim,&Allebeck,2011). In northeastern
Cambodia, Chassagne, Hul, Deharo, and Bourdy (2016) reported that 87% of Bunong people
used traditional medicine as a first step for treating diarrhea (
Chassagne et al., 2016).
The cultural belief system of people living in the Mekong area
The use of traditional medicine for diarrhea is also associated with local perceptions and
beliefs that can influence the management of the disease by villagers. Shawyer, Gani,
Punufimana, and Seuseu (1996) identified four main factors in the belief system influencing
decision making and behavior including diagnostic categories, explanatory models, per-
ceived ill-effects, and appropriate treatments (
Shawyer et al., 1996). Here, I present some
examples of beliefs and practices related to these four factors in the Mekong population.
In the Khon Kaen province of Thailand, diarrheal illnesses are classified into different
categories which have their own perceived causes and their own therapeutic practices
(
Shawyer et al., 1996). While most of these categories present similar features than those
from the biomedical classification, one hold “spirits” responsible for the manifestation of
diarrhea. In this case, the only treatment recommended by villagers is to ask a spirit
medium for ceremony to apologize to spirits. Als o, one of the most frequently cited causes
of diarrhea is centered around food taboos. This widespread belief involves the eating of
wrong food such as sour foods and fermented foods. Regarding therapeutic practices,
herbal medicine was reported in the treatment of some categories of diarrhea especially
the type called “tong sia” or “tong ruang” also described as a common watery diarrhea.
In rural Vietnam, mothers consider that diarrhea without fever is a minor illness and thus
can be treated by self-medication such as traditional therapies (
Le et al., 2011). In another study,
Vietnamese people living in urban area mentioned that traditional medicine is “much safer”
than Western medicine, and they often used it for mild symptoms (
Hoa, O
¨
hman, Lundborg, &
Chuc, 2007
). Similar perceptions were noted among four ethnic groups in northern Vietnam. In
this study, it was shown that ethnic minority caregivers recognized the danger signs of child
diarrhea. They administer home remedies such as herbal mixtures for minor episodes of diar-
rhea lasting 24 days, but they consult the communal health station if the diarrhea lasts more
than 4 days, reemerged shortly after recovery, or include high fever, very frequent defecation,
loss of weight, and lethargy (
Rheinla
¨
nder, Samuelsen, Dalsgaard, & Konradsen, 2011 ).
238 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
An important medical concept to consider when studying the management of diarrheal
illnesses is the hot-cold explanatory model for illnesses. In Vietnam,
Kaljee et al. (2004)
reported that diarrhea and dysentery are perceived as “hot” diseases that should be trea-
ted by “cold” medicine (
Kaljee et al., 2004). In this study, herbs are considered by
Vietnamese people as “cold,” while modern medicine is considered to be “hot” (Kaljee
et al., 2004
). For this reason, some informants reported to be reluctant to use Western med-
icine for diarrhea and dysentery.
In Thai and Cambodian medicine, “wind illness” has been reported as another explana-
tory model for diarrheal illnesses (
Chassagne et al., 2016; Muecke, 1979). The “hot-cold”
balance and “wind illness” are linked to the humoral theory which states that the human
body is composed of four basic elements, namely, earth, water, fire, and wind. In this the-
ory, health is maintained through equilibrium, and a dysfunction of one of these elements
can cause illnesses (
Chassagne, Deharo, Punley, & Bourdy, 2017; Shawyer et al., 1996).
Organoleptic properties (i.e., taste, smell, color, shape) have also been reported as major
selection criteria of plants for diarrhea (
Ankli, Sticher, & Heinrich, 1999; Leonti, Sticher, &
Heinrich, 2002
). In traditional Thai medicine, the taste of drug is of utmost importance to iden-
tify antidiarrheal plant species, and Thai people consider that astringent tasting plants have
healing properties for diarrhea (
Neamsuvan, Phumchareon, Bunphan, & Kaosaeng, 2016). In
Cambodian medicine, astringent taste is also a criterion to select the plant species used for
treating diarrhea (
Chassagne et al., 2016). Odor can also play a role in the selection of plants
for diarrhea. For example, Paederia foetida L., an herbaceous plant native to Asia, has a strong
sulfurous odor resembling that of a flatus or feces. This plant is widely used in Asia for intesti-
nal disorders such as diarrhea and dysentery because native doctors think that the odor given
off by the leaves identifies them as a specific treatment (
Steinmetz, 1961). In Vietnam, the plant
has been reported for the treatment of diarrhea and dysentery (
van Sam, Baas, & Keßler, 2008).
Pharmacological validation of plants used for diarrhea
The use of medicinal plants for diarrhea is based on empirical knowledge of traditional
healers and villagers and influenced by sociocultural factors. In a scientific context, the ethno-
medical use of plants can be validated by pharmacological assays to provide rationalization of
their presumed clinical effect. In this approach, in vitro models are used as a first step due to
their low cost, simplicity, lack of ethical constraints, and the small amount of material required
(
Brusotti, Cesari, Dentamaro, Caccialanza, & Massolini, 2014; Butterweck & Nahrstedt, 2012).
However, in vitro tests are less clinically relevant than in vivo assays which must be consid-
ered as a second step in the validation process of medicinal plants (
Houghton, Howes, Lee, &
Steventon, 2007
). Furthermore, clinical trials are the last step in the process to verify or refute
empirical knowledge, and only well-designed randomized double-blind placebo-controlled
clinical studies should be used (
Gertsch, 2009).
In the case of plants used for diarrhea, several pharmacological actions can be involved
in the observed clinical effect (
Fig. 7.2). First, plants can act on the signs and symptoms of
diarrhea (e.g., frequent loose stools, abdominal cramps), and thus exhibit anti-diarrheal
and/or antispasmodic effect. Second, plants can act on the pathophysiology of diarrhea
(e.g., alteration in intestinal motility, abnormal water adsorption or electrolyte secretion
into the intestinal lumen) and display antimotility or antisecretory activity. Third, plants
239Traditional medicine for diarrheal diseases in the Mekong Basin
Medicinal Plants as Anti-infectives
can target the specific agents causing diarrhea (e.g., viruses, bacteria, and parasites), and
show antibacterial, antiviral or antiparasitic activity. This leads to the analysis of the main
pharmacological models currently employed for evaluating plants used for diarrhea.
Models assessing the effect of plants on the signs and symptoms of diarrhea
Antidiarrheal effect
One of the most popular ways to evaluate the antidiarrheal effect of plants is to induce a diar-
rhea in an animal model (e.g., mice or rats) and to monitor changes in feces consistency, mass,
and frequency with and without administration of plant extracts. The in vivo castor oil-induced
diarrhea model is the most employed one and consists of administering a castor oil (a
vegetable oil obtained from the bean of Ricinus communis L.) treatment to mice or rats (
Kinuthia,
Muriithi, & Mwangi, 2016; Palla et al., 2015
). Other agents are also used to induce diarrhea such
as magnesium sulfate, and lactose (
Boakye, Brierley, Pasilis, & Balemba, 2012; Uddin et al., 2005).
Spasmolytic activity
To evaluate the antispasmodic effect of plants, ex vivo models (i.e., isolated intestinal tissues
taken from a living animal) are usually employed. Isolated rabbit jejunum is widely used due
FIGURE 7.2 Current pharmacological models used to evaluate the effect of plants treating diarrhea. In red: phar-
macological models targeting microbes causing diarrhea. In brown: pharmacological models acting on the diarrheal
symptoms and pathophysiology. In blue: pharmacological model studying the change in intestinal microbiota.
240 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
to its spontaneous rhythmic contractions in controlled experimental conditions, avoiding the
use of an agonist to test the relaxant activity (
Kinuthia et al., 2016; Saqib et al., 2015). In a
lesser manner, isolated guinea ileum is also employed, but this model requires the use of an
agonist (e.g., acetylcholine) to induce ileum contraction (
Ghayur & Gilani, 2005).
By using the same ex vivo models, additional experiments can be performed to assess
the mechanism behind the spasmolytic activity. For example, a high concentration of K
1
can be added to the ex vivo preparation to test a potential calcium channel blocking activ-
ity. Indeed, a high concentration of K
1
induces a contraction of smooth muscle through
influx of Ca
21
, and extracts or compounds inhibiting this contraction are known to block
calcium channels (
Palla et al., 2015; Saqib et al., 2015). Also, standard antagonists such as
naloxone (μ opioid blocker), propranolol (β-adrenergic blocker), tamsulosin (α1-adrenergic
blocker), and yohimbine (α2-adrenergic blocker) can be used to determine the type of
receptor involved in the spasmolytic activity (
Kinuthia et al., 2016).
Models assessing the antimotility and antisecretory activities
Antimotility activity
Inhibition of intestinal motility by plants can be assessed by using the gut meal travel
test. In this model, castor oil is used as a pharmacological agent to increase peristaltic
activity, and the transit of a charcoal meal (5%10% activated charcoal in an aqueous sus-
pension) along the small intestine is measured. A peristaltic index is usually calculated by
comparing the distance traveled by the charcoal plug from pylorus to the cecum to the
total length of the small intestine (
Kinuthia et al., 2016; Palla et al., 2015).
Antisecretory activity
Under physiological conditions, the small intestine (mainly intestinal crypts) secretes fluid
and electrolytes to prepare for digestion, and this process is balanced by fluid absorption by
the intestinal villi (
Farthing, 2006). In diarrheal diseases, particularly during cholera, entero-
toxigenic bacterial infection, and rotavirus infection, the normal balance between absorption
and secretion in the crypt-villus axis is disrupted. A hypersecretion across the intestinal lumen
occurs and induces an excess in intestinal fluid losses. This secretory process results predomi-
nantly from the active secretion of chloride ions through cystic fibrosis transmembrane con-
ductance regulator (CFTR) channels or calcium-activated chloride channels (CaCCs) (
Farthing,
2006; Thiagarajah, Donowitz, & Verkman, 2015
). In secretory diarrhea, CFTR channels are
mostly activated by the bacterial enterotoxins released in cholera and ETEC infection, while
CaCCs channels seem to be the main target of rotavirus infection and drug-induced secretory
diarrhea (
Thiagarajah & Verkman, 2013). Other pathways are also involved in the intestinal
fluid secretion and thus could serve as alternative therapeutic targets such as Na/K/Cl trans-
porters, calcium-sensing receptors, and K
1
channels (Thiagarajah et al., 2015).
To date, the main pharmacological assays used to evaluate the antisecretory activity of
plant extracts are (1) animal-based models aiming to measure the fluid accumulation in
the intestine, using ligated intestinal loop, after administration of toxins (e.g., cholera toxin
241Models assessing the antimotility and antisecretory activities
Medicinal Plants as Anti-infectives
or heat-stable enterotoxin of ETEC), castor oil, or prostaglandin E2 (Kinuthia et al., 2016;
Palla et al., 2015; Vela
´
zquez et al., 2012
). These experiments are also called enteropooling
assays; (2) ex vivo models aiming to evaluate the action on ions transports (Na
1
absorption,
Cl
2
secretion) across the intestinal epithelium by using intestinal pieces of mice mou nted
in Ussing chambers (Makrane et al., 2019); (3) in vitro tests aiming to assess the CFTR
channel inhibitory activity in intestinal cells (e.g., T84, Caco-2, HT29-CL19A) or other types
of cells (e.g., recombinant FRT) (
Akrimajirachoote, Satitsri, Sommart, Rukachaisirikul, &
Muanprasat, 2020; Dawurung et al., 2020; Gabriel et al., 1999; Ma et al., 2002; Ren et al.,
2012; Zhang, Fujii, & Naren, 2012; Zhang et al., 2014
).
Models assessing the antiinfective properties
Antibacterial activity
In vitro models are commonly used to assess the antibacterial activity of plant
extracts by targeting diarrhea-causing bacteria (e.g., E. coli, Salmonella spp., Shigella boy-
dii, Shigella flexneri, Shigella sonnei,andV. cholerae). Traditional strategies aim at killing
or preventing the growth of bacteria (
Chassagne et al., 2020; Porras et al., 2020). For
this purpose, different methods have been described such as the disk diffusion assay
(or agar diffusion method), the agar dilution method, and the broth microdilution test
(
Alanı
´
s, Calzada, Cervantes, Torres, & Ceballos, 2005; De Esparza, Bye, Meckes, Lo
´
pez,
&Jime
´
nez-Estrada, 2007; Madikizela, Ndhlala, Finnie, & Van Staden, 2012
). Due to its
simplicity, the disk diffusion method is widely employed, but the diffusion of the sub-
stance will depend mainly on its polarity a nd molecular weight, and thus prevent any
comparison of different samples (
Tan & Lim, 2015). For quantitative analysis, agar dilu-
tion and the broth microdilution methods are more appr opria te (
Wiegand, Hilpert, &
Hancock, 2008
).
Because killing or preventing the growth of bacteria leads to strong selective pressure, and
thus development of resistance, other antibacterial approaches have been developed including
targeting virulence factors (
Rasko & Sperandio, 2010). Among the latter, we can mention the
interaction of plant extracts with bacterial toxins. For example, the binding properties of natu-
ral substances to heat-labile enterotoxin from ETEC or to cholera toxin have been studied
using an ELISA assay and an SDS-PAGE analysis, respectively (
Chen et al., 2007; Vela
´
zquez
et al., 2012
). More recently, antibiofilm and quorum quenching assays have been used to tar-
get biofilm produced by bacteria and to interfere with bacterial signaling molecules (e.g., AI-
2) (
Castillo, Heredia, Arechiga-Carvajal, & Garcı
´
a, 2014; Oh et al., 2017).
Although less common, other in vitro tests have been reported to be used for assessing
the effect of plant extracts on the adherence and invasiveness of bacterial enteric patho-
gens to epithelial cells (
Brijesh et al., 2006).
Finally, animal-based studies have also been employed to evaluate the antibacterial
activity of plant extracts. In this case, a bacteria causing diarrhea is administered to ani-
mals and different physiological, biochemical, hematological, and histopathological para-
meters are measured (
Choi et al., 2011; Fokam Tagne, Noubissi, Fankem, & Kamgang,
2018; Mukherjee et al., 2013; Noubissi et al., 2019; Thakurta et al., 2007).
242 7. Medicinal plants used as antidiarrheal agents in the lower Mekong basin
Medicinal Plants as Anti-infectives
Antiviral and antiparasitic activity
While bacteria are the most common pathogens used in pharmacological studies, viruses
and parasites are also employed to explain the clinical effect of plant extracts used for diarrhea.
Rotaviruses are the main viruses to be tested as they represent the major causes of infantile
gastroenteritis worldwide (
Marcos & DuPont, 2007). Several rotaviruses strains have been
reported to be used in pharmacological studies, including Human (HCR3), simian (RRV or
SA-11 strains), porcine (KJ2051), and bovine (KJ561) rotaviruses. These strains were multi-
plied in monkey kidney cells (i.e., MA-104 or TF-104 a cloned derivative of MA-104), then dif-
ferent strategies were used to determine the antirotavirus effect such as blocking effect of the
viral infection, virucidal activity, or reduction of infection particles produced postinfection
(
Gonc¸alves et al., 2005; Kwon et al., 2010; Te
´
llez, Te
´
llez, Ve
´
lez, & Ulloa, 2015).
Regarding the antiparasitic effect, most of the studies focused on the antiprotozoal
activity of natural substances either in vitro or in vivo. In vitro cytotoxicity activity of these
substances were evaluated against trophozoites of Giardia lamblia (
Brandelli, Giordani, De
Carli, & Tasca, 2009
), trophozoites of Entamoeba histolytica (Calzada, Bautista, Ye
´
pez-Mulia,
Garcı
´
a-Hernandez, & Ortega, 2015
), and the intestinal protozoa Blastocystis hominis
(
Sawangjaroen & Sawangjaroen, 2005). Infection with trophozoites of G. lamblia in animal
model was also reported (
Barbosa, Calzada, & Campos, 2007).
Other models
Last but not least, new pharmacological models have been developed to evaluate the
interaction of plants with gut microbes. Indeed, there is growing evidence showing that
plants interact with the gut microbiota and exhibit beneficial health effect on gastrointesti-
nal disorders (
Thumann, Pferschy-Wenzig, Moissl-Eichinger, & Bauer, 2019). With the
emergence of new technologies such as metagenomics, metabolomics, and metatranscrip-
tomics, researchers are now able to study the complex relationship between gut microbio-
ta, genes, and metabolites (
Feng, Ao, Peng, & Yan, 2019). For example, Li et al. (2019)
studied the effect of Panax ginseng polysaccharides on the diversity and composition of the
gut microbiota in mice with antibiotic-associated diarrhea. The authors showed that P. gin-
seng polysaccharides positively affected the gut microbiota by increasing beneficial bacte-
ria such as Lactobacillus or Lactococcus species, and also promoted the recovery of the
mucosa by reversing carbohydrate, amino acid, and energy metabolism to normal levels.
Altogether, these effects helped to alleviate the symptoms of diarrhea (
Li et al., 2019).
This emerging field of study opens the way for a better understanding of the interaction
of plant with gut microbiota in diarrheal diseases, and more researchers shou ld integrate
these experiments into their laboratory workflow when studying plants used for diarrhea.
Medicinal plants used for diarrhea in the lower Mekong basin
Literature search methodology
A review of the scientific literature was performed to identify medicinal plants used in
traditional medicine for the treatment of diarrheal illnesses. Electronic databases (i.e.,
243Medicinal plants used for diarrhea in the lower Mekong basin
Medicinal Plants as Anti-infectives