Swagat Kumar Das, Dibyajyoti Samantaray and Hrudayanath Thatoi*
Department of Biotechnology, College of Engineering and Technology, Biju Patnaik, University of Technology, hubaneswar-751003, Odisha, India
Received Date: October 26, 2014; Accepted November 28, 2014; Published Date: December 01, 2014
Citation: Das SK, Samantaray D, Thatoi H (2014) Ethnomedicinal, Antimicrobial and Antidiarrhoeal Studies on the Mangrove Plants of the Genus Xylocarpus: A Mini Review. J Bioanal Biomed S12:004. doi: 10.4172/1948-593X.S12-004
Copyright: © 2014 Das SK, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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Mangroves being stress tolerant plants possess unique metabolites with significant amount of bioactive compounds which could be isolated and evaluated for possible drug development with suitable biotechnology tools. The mangrove genus Xylocarpus comprises of four species viz. Xylocarpus granatum (Koenig), X. moluccensis (lamk.) and X. mekongensis Pierre and X. rumphii. However, X. rumphii is a less abundant mangrove plant. There have been reports that different species of Xylocarpus are used ethnomedicinallly for treatment of various diseases such as fever, malaria, cholera, diarrhoea, swelling of breast, elephantiasis, inflammation, dyslipidemia, pain, hyperglycaemia etc. Recent studies revealed that the extracts from different parts of the plant such as leaves, stem, bark and fruits possess phytoconstituents like alkaloids, glycosides, steroids, limnoids, terpenoids, flavonoids, tannins and other phenolics. Further, it has been established that the different solvent extracts of the plants have exhibited antimicrobial and antidiarrhoeal activities against a number of human pathogens which could be correlated to their phytoconstituents such as flavonoids, alkaloids, limnoids, tannins etc. The present study is aimed at compiling information on phytochemical, pharmacological and ethnomedicinal properties of mangrove plants of genus Xylocarpus, with a view to critically assess the legitimacy of the use of these plants for antimicrobial and antidiarrhoeal activities as well as providing directions for further research.
Mangrove; Xylocarpus; Ethnomedicine; Phytochemical; Antimicrobial; Antidiarrhoeal
Plants and plant based metabolites are widely used in ethnomedicinal practices around the world. Plants are rich in wide variety of secondary metabolites such as tannins, terpenoids, alkaloids, flavonoids, flanonoids, phonolics, glycosides, saponins, and steroids etc. which have been used for treatment of various diseases for ages. Like any other plant communities, the mangrove plants have also been reported for there ethnomedicinal uses. Mangroves are the unique plant communities inhabiting the estuarine and intertidal regions of both tropical and subtropical coasts are largely confined to the region between 30° north and south of the equator. These are salt tolerant plant communities comprising of trees, herbs, shrubs and grasses. There are about 39.3 million acres of mangrove forests in the warm coastlines of tropical oceans all over the world distributed in 112 countries and territories . Out of the given total mangrove species and their associates, the number of exclusive or true mangrove species in the world is 68 and they belong to 27 genera. Approximately 55 species of mangroves from 22 genera were distributed in Indian Ocean region . These plants inhabit an extremely challenging environmental abiotic stress condition enumerated by high salinity, water logging condition, high and low tides of water, high temperature, low oxygen, low nutrition, muddy anaerobic soil and strong wind conditions where other plants cannot grow. Along with these abiotic stress factors, the insects and microorganisms and other anthropological condition also contribute a large in developing the biotic stress to these unique plant community. However, these mangrove plants adapted well to these ecological hostile condition by alterations in their physiological processes resulting in the synthesis of novel chemical compounds that offer protection to these plants against various biotic and abiotic stresses mentioned above . A number of these phytocompounds or secondary metabolites have significant pharmacological properties are being used traditionally for treatment of number ailment .
For centuries, mangroves have been traditionally used for food (fruits and nectar), feed and medicinal purposes in different parts of the world. They are well known to produce natural metabolites with diverse biological activities. Several mangrove plants viz. Acanthus ilicifolius, Aegiceras majus, Avicennia africana, A. marina, A. officinalis, Ceriops caudolleana, Exocoecaria agallocha, Kandelia rhecdi, Nypa fruticans, Rhizophora mangle, R. mucornata and Sonneatia caseolaris are widely used by local medical practitioners in many countries like Africa, South East Asia, South America and Australia including India. These plants are used to cure some diseases like leprosy, elephantiasis, tuberculosis, malaria, dysentery, ulcers and some skin diseases . The mangroves plants are reported to contain some unique class of diverse compounds that includes phorbol esters, phenolics and related compounds, steroids, triterpenes, and their glycosides, tannins, other terpenes and related compounds, flavonoids, tannins, anthocyanins, alkaloids etc . A number of these compounds or secondary metabolites have significant medicinal properties that can be exploited in shaping better human health care needs.
The genus Xylocarpus consists of ethnomedicinally important mangrove plant species viz. Xylocarpus granatum, X. moluccensis, X. mekongensis, X. rumphii that are used in traditional medicine practices. Extracts of leaves, barks and fruits of these plants have been reported for various ethnomedicinal uses such as fever, malaria, inflammation, dysentery, diarrhoea, cholera, abdominal problems, diabetes, elephantiasis, antimicrobials etc. Recently, these plants are also reported for their antioxidant, anticancer, antidiabetic, antidyslipidemia, antimicrobials, antidiarrhoeal, antifilarial, antiulcer and cardiotonic properties [6-14]. The comprehensive uses of Xylocarpus species in human sufferings provide strong evidence of their healing power and demands further research.
The present review aims to compile the ethnomedicinal, antimicrobial and antidiarrhoeal reports of different mangrove plants belonging to the genus Xylocarpus.
Species: Xylocarpus granatum, X. moluccensis, X. mekongensis
The genus Xylocarpus consists of trees growing around littoral of the tropical Indian Ocean and extending to the Pacific Islands distributed widely in the coastal areas of South-East Asia, Australia and East Africa . The genus Xylocarpus belonging to the family Meliaceae has three distinct species in India viz. Xylocarpus granatum (Koenig), X. moluccensis (lamk.) and X. mekongensis Pierre . However, it has been reported that another species i.e. X. rumphii belonging to the genus Xylocarpus genus inhabits sandy and rocky seashores in the tropics like Srilanka, Malaysia and some parts of Australia . Out of these four species, X. rumphii appears to be less common in distribution and abundance. X. granatum commonly known as a ‘cannon ball tree’ is a large spreading medium mangrove tree growing in inter-tidal silty clay soil, with rounded coriaceous leaves, smooth thin bark, and abundant red heartwood forming well developed buttresses surrounding the trunk base. Mature fruits hang on the mother plants almost throughout the year. Diameter of the fruit is up to 20 cm or slightly more, yellowish brown fruit coat, completely round with long woody stalk. X. moluccensis is a medium-sized crooked, much branched ever green tree up to 10 m tall growing generally on the sandy or rocky bay, away from the frequent tidal inundation. They are found on the fringes of backwater creeks. They have pointed leaves, deeply serrated bark and an undistinguished timber. The fruit is the size of a mandarin orange of 5-7 cm in diameter. The X. mekongensis is a medium sized tree that grows generally on the inter-tidal silty but consolidated clay or on the sandy or rocky bay. The plant has well developed aerial blunt end pneumatophores or root suckers. It has green coloured fruit of diameter generally not exceeding 15 cm. The morphological features and distribution of these plants have been summarised in (Table 1).
|Mangrove species||Features||Occurrence||Ethnomedicinal uses|
|X. garanatum||Plant: Small to medium-sized, glabrous, evergreen tree
Leaf: Paripinnate, the leaves
have 1 or 2 pairs of leaflets. The leaflets are characteristically obovate with a rounded apex. The lamina is gradually tapering towards the thick, distinct petiolule. The lamina is coriaceous with a shining surface.
Bark: Trunk surface is pale, smooth with its thin bark peeling in flakes or patches
Fruit: large, globose up to 20–30 cm across.
Flowers: Flowers small in axillary few-flowered cymose panicles, 4-7 cm long.
Root: Erect, conical knee roots are absent but the horizontal cable roots develop into ribbon-like plank roots
|East Africa, South east asia, Australia
and Indian Costal region
|Bark: cholera, fever, malaria, diarrhoea
Leaves: microbial, diarrhoea
Fruits: hyperglycaemia, dyslipidemia,idiarrhoea
|X. moluccensis||Plant: Moderate-sized trees (5-20m in height) with well-developed woody trunk
Leaf: Leaflets ovate
Bark: Bark longitudinally fissured,
Fruit: Fruit elliptical (8-12cm in diameter) containing 5-10 seeds.
Flowers: Flowers tiny white to pinkish in clusters on an inflorescence.
Root: small or no buttress roots, many peg-shaped, pneumatophores.
|Coastal region of
India, Bangladesh, Burma, Ceylon Malaya and Indonesia
|Bark: fever, malaria, astringent, febrifuge, dysentery, diarrhoea.
Leaves: bacterial, cancer and inflammation
Fruits: aphrodisiac, cure
for elephantiasis and swelling of the breasts, bactericidal. hyperglycaemia and dyslipidemia
|X. mekogenesis||Plant: Tree 5-20m tall
Leaf: Paripinnate, the leaves have 1, 2 or 3 pairs of leaflets. The leaflets are ovate or oblong with a pointed or blunt tip. The surface of the lamina is flat.
Bark: Trunk surface is rough, dark brown, fissured with the bark peeling in long thick narrow strips.
Fruit: subglobose up to 10 cm across, with 10–15 pyramidal seeds.
Flowers: The inflorescence 10 cm long. The flowers are creamy white with an attractive orange red disc
Root: Horizontal cable roots produce vertical, conical, laterally compressed knee roots or pneumatophores which may grow up to 30 cm tall
|Bengal, Burma, the Andaman’s, the Malay Peninsula and Archipelago, Australia, Fiji
|Bark: malaria, diarrhoea, antinociceptive activities, inflammation and oxidant
Fruits: elephantiasis, preventing swelling of the breast
Table 1: Botanical features, distribution and ethnomedicinal uses of Xylocarpus plants.
Ethnomedicine refers to the study of traditional medicinal uses practised by different ethnic groups in concerned with the cultural interpretation of health, diseases and illness. The practice of ethnomedicine involves written documents, experience and knowledge that have been shared from generation to generation . The ethnomedicinal study plays a vital role in drug discovery and anthropological research. It constitutes the scientific backbone for developing active therapeutics based on traditional medicines of different human indigenous societies.
Ethnomedicinal studies on X. granatum have been documented by several researchers. It has been reported that extracts of different parts of X. granatum are used traditionally as relief for fever including malaria, inflammation, dysentery, cholera and other abdominal problems in certain parts of the globe [19,20]. Different extracts of roots, barks , fruit seed coat, seed kernels  are used to treat cholera and treatment of diarrhoea.
X. mekongensis, another species of the genus Xylocarpus has been reported to have ethnomedicinal uses. The bark and pneumatophore of X. mekongensis possess antimalarial, antidiarrhoeal and antinociceptive activities [3, 22,23]. Traditionally X. mekongensis is used as an astringent and in the treatment of fever, dysentery, diarrhoea . The kernel root of this plant also reported for their anti-inflammatory properties .
Yet another species of the genus Xylocarpus i.e. X. moluccensis is also used in traditional medicinal practices as reported by several studies. The fruit and bark of X. moluccensis is used in the treatment of fever, malaria, antidiarrhoea, antiemetic, elephantiasis and swelling of the breast etc. . An ointment prepared from seed ash of the plant X. moluccensis along with sulphur and coconut oil is used for treatment of itch . The ethnomedicinal uses of the different species of the Xylocarpus plants have been summarized in (Table 1).
The mangrove plants that belong to the genus Xylocarpus have shown enormous ethno medicinal potential; however, few reports are available about their active principles responsible for their biological activities. The presence of alkaloids, flavonoids, monoterpnes, triterpenoids, tetratriterpenoids, limonoids, phenolic acids, steroids etc. has been reported in the leaves, stem bark and fruits of these plants [3,19]. Numerous alkaloids have been reported in the barks, roots and fruits extracts of X. granatum . Four alkaloids viz. N-methyl flindersine, chelerythrine, dihydrochelerythrine, acetonyl dihydrochelerythrine were isolated from the root barks of X. granatum . Besides, its fruits also contain many alkaloids like xylogranatinin, granatoin [28-30]. Flavonoids like catechin, epicathechin, kaempferol, 3-O-β-D-glucoside are found in different parts (bark, fruits and leaves) of the plant X. granatum [19,28,31]. Similarly, the bark of X. moluccensis is reported to contain flavonoids like catechin and epicatechin . X. granatum seeds are rich source of limonoid xylocarpin  and hispidol B . Its bark is rich in gedunin, xyloccensins L-V, 6-dehydroxyxylocarpin D [19,33-37]. Several limnoids viz. Xyloccensin (A-I), Xylocarpin, Humilin B are also reported in bark and leaves extracts of X. moluccenesis . The presence of four novel tetranotriterpenoids named xylogranatins A-D (1-4) with have been demonstrated by phytochemical exploration of seed extracts of X. garanatum . The seeds of X. granatum plant have been reported to contain rich sources of tirucallane-type triterpednoids . These plants are also reported to have many compounds of limonoids from its different species that include Gedunin group, Andirobin group, Mexicanolide group and Obacunol group . The mangroves X. granatum and X. moluccenesis are distinguished for producing antifeedant limonoids especially mexicanolides and phargmalins. Recently Protoxylogranatin, a new derivative of phargmalins has been isolated from X. granatum which plays a pivotal role in oxidative cleavage in biogenetic pathway to limonoid . X. granatum leaves are rich in cholesterol, campestrol, stigmasterol, sitosterol, 28-isofucosterol. Seeds and fruits of this plant contain some important sterols like ergosterol peroxide, β-sitosterol fatty acid esters . The Bark of X. granatum is reported to contain procyanidin B1, procyanidin trimer and pentamer . Similarly, bark of X. moluccensis are rich sources of variety of proanthocyanidins like procyanidin B1, procyanidin B3, procyanidin trimer, procyandin pentamer, procyanidin hexamer, procanidin decamer and procyandinin undecamer . However, very few compounds are reported in X. mekongensis. Compounds like xyloccensin, xylocarpin are reported in different extracts of X. mekongensis [3,43]. The different species of the genus Xylocarpus along with their major phytoconstituents and bioactivity are summarized in (Table 2).
|Major Phytoconstituents||Bioactivity||Compounds Isolated||References|
|4-hydroxybenzoic acid, ethyl 3,4- dihydroxybenzoate,
xylogranatinin, granatoin, N-Methylflindersine,
β-Sitosterol, β -Sitosterol β -D-glucoside
Gedunin and 1α-hydroxy-1,2-dihydrogedu., xyloccensin O , xyloccensin P , xyloccensin Q
Catechin, epicatechin, procyanidins of the B, trimer and pentamer
xyloccensins O-P, xyloccensins Q-V,
Xyloccensin L, xyloccensin K, xyloccensin IJ.
Chelerythrine and dihydrochelerythrine
|Procyanidin decamer , procyanidin undecamer
Catechin, epicatechin, procyanidin B1 , B3, procyanidin trimer , procyanidin pentamer , procyanidin hexamer, procyanidin decamer procyanidin undecamer
Xyloccensins X and Y
|Xylocarpin, xyloccensin|| [8-9,56-58]
Table 2: Phytochemical constituents and bioactivity of Xylocarpus species.
Antimicrobial and Antidiarrhoeal Activities of Xylocarpus Sp.
The phytochemicals as remedy for various ailments including microbial infections have been known for centuries which form the basis for their use in ethnomedicinal practices around the world . Recently, the indiscriminate use of antibiotiotics has led to the emergence of multidrug resistant microbial strains; hence the search for novel antimicrobial compounds is the need of the hour.
Phytochemicals possessing antimicrobial activities can provide an alternative source as the natural products contains diversified chemical compounds that can be exploited scientifically for development of novel drugs. In this respect, mangrove plants can play a very important role as they offer a very rich source of valuable bioactive compounds and thus merit serious consideration for the discovery of novel drugs having antimicrobial properties. The antimicrobial properties of the mangrove plants have been recently attracted the researchers’ worldwide since the mangrove plants possess strong antimicrobial compounds (viz. flavonoids, tannins, terpenoids, coumarins, alkaloids, lectins) that may act against a broad range of disease causing microorganisms. Patra and Mohanta  have reported the antimicrobial activities in several mangrove plants that include Avicennia marina, A. officinalis, Bruguiera gymnorrhiza, B.conjugate, B. sexangula, C. odorata, Ceriops decandra, Exoecaria agallocha, Heritiera littoralis, Rhizophora apiculata, R. mucronata, X. granatum.
The mangrove plants of genus Xylocarpus exhibited promising antimicrobial activities and are also reported for possession of several unique antimicrobial compounds. Several studies have shown that the bark, leaves and fruit extracts of the plant X. granatum exhibited effective antimicrobial activities against several Gram positive and Gram negative bacteria. The ethanol, petroleum ether, chloroform, carbon tetrachloride  and methanol [61,62] extracts of stem of X. granatum exhibited antimicrobial activity against various microbes like Staphylococcus aureus, S. epidermis, Shigella boydii, Proteus sp., Escherichia coli, Streptococcus pyogenes, Bacillus subtilis. Similarly, Rao and Chaitanya  reported the antibacterial and antiyeast activities of ethanolic extracts of leaf and stem (100 mg/ml and 300 mg/ml) of X. granatum. It has been suggested that different parts of the mangrove plant X. granatum exhibit antimicrobial properties which may be due to the presence of phytoconstituents such as alkaloids, flavonoids, tannins etc. 
Another species of the genus Xylocarpus, i.e. X. moluccensis also possessed promising antimicrobial properties as reported by various studies. The different parts like barks , pneumatophores , fruit husk , leaves  of X. moluccensis exhibited considerable antibacterial activity against a wide range of both Gram positive and Gram negative bacterial strains that include E. coli, Enterobacter aerogenes, Pseudomonas aeruginosa, Salmonella typhi, S. boydii, S. dysenteriae, S. flexneri, S. sonnei, Staphylococcus aureus, Staphylococcus epidermidis, S. pyogenes and Vibrio cholera, Klebsiella pneumoniae, Enterobacter aerogenes and Pseudomonas aeruginosa.
Amongst the three species of Xylocarpus, X. mekongensis have been least reported for its antimicrobial activities. However, Ahmed et al.  reported the antibacterial activity of different solvent extracts of bark of X. mekongensis against various bacterial strains viz. Vibrio cholera, S. flexneri, S. boydii, Salmonella typhi, S. paratyphi and S. aureus. The ethyl acetate and chloroform extracts of bark showed relatively higher antibacterial activity amongst the different solvent extracts studied. The details of the antimicrobial compounds from the different Xylocarpus species are described in (Table 3).
|Plant name||Plant part (s) used||Test method||Compounds identified||References|
|X. granatum||Ethanol extract of stem bark, methanolic extracts of rootlet and shoot||• Agar disc diffusion method
||Xyloccensin, procyanidin B3, catechin,
epicatechin, procyanidin B1, procyanidin trimer,
procyanidin pentamer, xyloccensin Q, gedunin,
alkaloids,xylocarpin, N-methylflindersine xylogranatins A-D
|X. moluccensis||Hexane, Benzene, Chloroform, Ethyl Acetate, Methanol, Acetone, Ethanol and Water extracts of leaves and stem;
methanol extract of
fruit husk; ethanol extracts of the pneumatophores
|• Agar disc diffusion method
• Agar cup-plate diffusion
|flavonoids, alkaloids and glycosides||[56,63,64]|
|X. mekongensis||methanol, ethyl acetate and chloroform extracts of bark||• Agar disc diffusion method
• Broth macro- dilution assay
|Saponins, tannins, flavonoids|||
Table 3: Antimicrobial activities of Xylocarpus species.
The antibacterial property [66,67] of the different species of the mangrove genus Xylocarpus can be attributed to the presence of different secondary metabolites like flavonoids, saponins, polyphenols. Some important antimicrobial phytochemicals isolated from the mangrove plants of genus Xylocarpus have been included in (Figure 1).
According to WHO census for developing nations, diarrhoea remains a major cause of infant mortality and morbidity . Though various drugs are available for treatment of diarrhoea still numerous side-effects (e.g. abdominal discomfort, dry mouth, nausea, constipation and headache) are associated with these drugs. In comparison to conventional drugs, numerous herbal antidiarrhoeal remedies from various medicinal plants are available having lesser side effects and better efficacy. The bioactive compounds from these plants exert their antidiarrhoeal activity by decreasing the gastrointestinal motility as well as the secretions in vivo . Phytoconstituents like tannins, tannic acid, flavonoids, alkaloids, sesquiterpenes, diterpenes, terpenes and terpenoids are present in many plants that may contribute to antidiarrhoeal activity. As part of the continuing research on antidiarrhoeal activity, mangroves plants have not been left out. Different mangrove species like Carapa moluccensis, C. obovata, Heritiera littoralis, R. apiculata, R. mangle, X. garantum, X. moluccensis and X. mekogenesis have been reported to exhibit antidiarrhoeal activity .
It has been reported that the extracts of different parts of two Xylocapus species such as X. granatum and X. moluccensis are traditionally used for treatment of diarrhea. The ethanolic bark and leaves extracts of X. granatum showed antidiarrhoeal activity in number diarrhoeal animal models. They were found to exhibit significant antidiarrhoeal activity in a dose dependent manner . The purging indices and percent purging indices for bark extracts of X. granatum were reported to be 32.09, 22.75% (500 mg/kg) and 14.07, 10.30% (1000 mg/kg) and for leaves extract as 51.56, 40.66% (500 mg/ kg) and17.62, 28.83% (1000 mg/kg) respectively. The decreased percent purging indices represent the potential antidiarrheal activity of bark and leaf extracts. In another experiment, the methanol extracts of X. granatum bark has been reported for their antidiarrhoeal activities in experimental castor oil and magnesium sulphate induced by diarrhoeal mice. The methanol extract showed dose-dependent antidiarrhoeal activity in both models at 250 and 500 mg/kg dose as evident by reduced number of faeces and total number of diarrhoeic faeces. The antidiarrhoeic activity of these extracts may be due to antisecretory mechanism, decreased water reabsorption or delayed gastrointestinal transit . Lakshmi et al.  also reported that fruit seed coat of X. garantum showed promising antidiarrheal activity at 500 mg/kg dose level in castor oil induced diarrhoeal mice model. The ethanol extracts of the fruit on further fractionation leads to isolation of many bioactive molecules  like gedunin, photogedunin, palmitic acid as listed in (Table 4).
|Plant name||Plant part (s) used||Test method||Compounds identified||References|
|X. granatum||Ethanol extract of stem bark, leaves and fruits||• Castor oil induced diarrhoeal model
||Gedunin, Photogedunin, Palmitic acid.
Flavonoids, tannins, saponins, anthraquinone
|X. moluccensis||Methanol extracts of bark||• Magnesium sulphate-induced diarrhea models.
• Gastrointestinal motility model
• The disc-diffusion method
Table 4: Antidiarrhoeal activities of Xylocarpus species.
Another species of the mangrove plant that belongs to the Xylocarpus genus i.e. X. moluccensis is also reported for it’s antidiarrhoeal activities. The methanol bark extracts of X. moluccensis exhibited significant antidiarrhoeal activity in castor oil and magnesium sulphate induced diarrheal mice models at 250 and 500 mg/kg doses [21,22]. Structures of some important antidiarrhoeal compounds isolated from Xylocarpus plants have been included in (Figure 2).
Possible Mechanism of Action
Although there are very few reports are available on the on the isolated compounds from the Xylocarpus species, but assumptions can be made about the possible mechanism of action of these mangrove isolates on their antibacterial and antidiarrhoeal activities. The Xylocarpus plants are known for the occurrence of a characteristic compound called limonoids that have a wide spectrum of biological activities, particularly insecticidal action . Some of the other phytochemical compounds such as glycosides, saponins, tannins, flavonoids, terpenoids, and alkaloids are also reported to have antimicrobial activity [63,73]. The phytochemical screening of these Xylocarpus plants have shown the presence of diverse class of compounds like alkaloids, terpenoids, tannins, glycosides, saponins, steroids, coumarins etc. which may be responsible for its antimicrobial activities against a wide range of microbes including Gram positive and Gram negative bacteria, yeast, fungi .
Diarrhoea is usually a result of gastrointestinal infection, which can be caused by a variety of bacterial, viral and parasitic organisms. Further, disturbances in the transport of electrolytes and water in the intestines give rise to diarrhoea leading to increased luminal osmolarity, increased electrolyte secretion, decreased electrolyte absorption and deranged intestinal motility causing a decreased transit time . Studies on X. granatum, and X. moluccensis revealed that these plants are rich in potential antidiarrhoeal bioactive compounds like tannins, tannic acid, flavonoids, alkaloids, sesquiterpenes, diterpenes, terpenes and terpenoids  that can be utilized in antidiarrhoeal drug development . The complex content of chemicals derived from these plants may have multiple targets of action and might therefore have several potential effects against diarrhoeal disease. The involvement of synergistic effects of astringent and antibacterial effect in combination with decreased intestinal movements might be responsible for their antidiarrhoeal potentials.
Future Prospects and Conclusion
The mangrove plants inhabit a unique ecological habitat exemplified by various stress conditions like high salinity, water logging, low oxygen condition, light stress, low nutrition conditions are reported to be biochemically unique and possess several bioactive compounds. Compounds isolated from the mangrove species have the potential to act as lead compounds for drug discovery. The different mangrove species of Xylocarpus possess significant pharmacological activities which can be pharmaceutically exploited. These plants have shown promising therapeutic applications in treatment of various ailments particularly in microbial infection and diarrhoea as reported by various ethnomedicinal and experimental studies. Even though extracts from mangroves and mangrove-associated species possess therapeutically activity moieties against a number of diseases, the specific metabolites responsible for these bioactivities are remained to be elucidated.
The bioactive compounds isolated from mangrove plants like Xylocarpus have advantages over the conventional medicines as the ethnomedicinal studies suggested that the diversified chemical content from these plants have multiple targets of action and might therefore have several potential therapeutic effects against diarrhoeal diseases. The involvement of synergistic effects of astringent and antibacterial effect of these plant extracts in combination with decreased intestinal movements may play vital role for their antidiarrhoeal potentials. However, safety, adverse effects and toxicity assays of these plant products has to be carried out in order to have a basis of these mangrove plant species to be recommended as phytomedicines useful against diarrhoea. Though many plants have been used in folklore medicine worldwide, recently, extracts from mangroves and their associated species have been proven to possess antimicrobial activities against a number of human, animal and plant pathogens.
The information presented in this review clearly indicates that the different mangrove species of Xylocarpus viz. X. granatum, X. moluccensis and X. mekogenesis possess pharmacologically active compounds such as alkaloids, flavonoids, limonoids, terpenoids, phenolic glycosides etc. having enormous therapeutic potential in alleviating a number of ailments. However, bioactivity guided isolation of these phytoconstituents is needed to establish the activity-structure relationship that may reveal the bioactive compounds responsible for different pharmacological activities in general and antimicrobial and antidiarrhoeal activities in particular.