ArticlePDF Available

The in vitro Antibacterial Activity and Ornamental Fish Toxicity of the Water Extract of Indian Almond Leaves (Terminalia catappa Linn.)


Abstract and Figures

Objective __ To determine concentration of tannin, an antimicrobial substance, in the water extract of Indian almond leaves (Terminalia catappa Linn.), evaluate in vitro antibacterial activity against bacteria isolated from aquatic animals, and assess toxicity of the extract in three species of ornamental fish: a guppy, a fancy carp, and the Siam fighting fish. Materials and Methods __ The dried leaves of Indian almond were extracted with water for 1, 3, and 7 days. Then, the amount of tannin in the extract was measured. Based on tannin analysis, only the extract for 3 days was used in this study. For in vitro antimicrobial activity test, 15 strains of bacteria isolated from ill aquatic animals were used. Minimal inhibitory concentration (MIC) of the extract was determined by agar dilution technique. For in vivo toxicity test, guppies, fancy carps, and Siamese fighting fish, with 30 fish in each species, were used. Fifty percent lethal concentration (LC50) was also determined.
Content may be subject to copyright.
36 «“√“√—µ«·æ∑¬»“µ√å ¡¢. ªï∑’Ë 18 ©∫—∫∑’Ë 1 ¡°√“§¡ - ¡‘∂ÿπ“¬π 2551
The in vitro Antibacterial Activity and Ornamental
Fish Toxicity of the Water Extract of Indian
Almond Leaves (Terminalia catappa Linn.)
Nantarika Chansue1* Nongnut Assawawongkasem2
Objective __ To determine concentration of tannin, an antimicrobial substance, in the water
extract of Indian almond leaves (Terminalia catappa Linn.), evaluate in vitro antibacterial activity
against bacteria isolated from aquatic animals, and assess toxicity of the extract in three species
of ornamental fish: a guppy, a fancy carp, and the Siam fighting fish.
Materials and Methods __ The dried leaves of Indian almond were extracted with water for 1, 3,
and 7 days. Then, the amount of tannin in the extract was measured. Based on tannin analysis,
only the extract for 3 days was used in this study. For in vitro antimicrobial activity test, 15 strains
of bacteria isolated from ill aquatic animals were used. Minimal inhibitory concentration (MIC) of
the extract was determined by agar dilution technique. For in vivo toxicity test, guppies, fancy
carps, and Siamese fighting fish, with 30 fish in each species, were used. Fifty percent lethal
concentration (LC50) was also determined.
Results __ Total tannin levels of the extracts for 1, 3, and 7 days were 4.02, 13.60, and 14.08
mg/ml, respectively. For antimicrobial test, MIC of the extract for 3 days was ranged from
0.8-2.0 mg/ml. For toxicity test, a guppy were more sensitive to the extract than a fancy carp
and the Siamese fighting fish, respectively. In a guppy, a fancy carp, and the Siamese fighting
fish, LC50 at 24 hours were 6.2, 7.6 and 8.6 mg/ml; LC50 at 48 hours were 5.4, 7.0 and
8.2 mg/ml; LC50 at 72 hours were 5.8, 5.9 and 7.6 mg/ml; and LC50 at 96 hours were 5.6,
5.8 and 7.0 mg/ml, respectively.
Conclusion __ This study indicated that the extract had a potential to use as an antibacterial
alternative for ornamental fish culture.
KKU Vet J. 2008;18(1):36-45
Key words: Aeromonas hydrophila; Fish; Indian almond leaves; Toxicity
1Veterinary Medical Aquatic Research Center, Department of Medicine, Faculty of Veterinary Science, Chulalongkorn University,
Pathumwan, Bangkok, 10330, Thailand.
2 Student of Master Degree, Department of Medicine, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok,
10330, Thailand.
* Corresponding author:
KKU. Vet. J. Vol. 18 No. 1 JANUARY - JUNE 2008
Indian almond tree (Terminalia catappa Linn.) is a Combretaceous plant (tropical
almond family), presenting throughout any region of Thailand. The plant is a large tree, which can
reach up to 30 m height with a thick broad trunk; the leaves cluster toward the end of the
branches with glossy, obovate blades mostly 8-30 cm in length and turn red before turning
brown and falling [1].
In Southeast Asia, leaves and barks of Indian almond tree are widely used in human as
a folk medicine to treat dermatosis, hepatitis, thrush and other oral infections, and intestinal
ailments in children. Decoction of the leaves is used to treat indigestion, furred tongue, bronchitis,
and tuberculosis. The crushed leaves mixed with coconut oil or coconut cream were used to
relieve muscle pain from fractures and sprain [1]. On the other hand, in modern medicine, many
pharmacological studies on various extracts of the leaves and barks have been reported to
possess anti-cancer [2], antioxidation [3], anti-HIV reverse transcriptase [4], hepatoprotection
[5], anti-inflammation [6], aphrodisiac activities [7], antifungal properties againt Pythium ultimum,
Rhizoctonia solani, Sclerotium rolfsii, and Aspergillus fumigatus [8], and antibacterial properties
against; Staphylococcus epidermidis, S.aureus, Bacillus cereus, B. subtilis, and Pseudomonas
aeruginosa [9].
The chemical compositions of this plant consist of tannins (punicalagin, punicalin, terflavin
A and B, tergallagin, tercatain, chebulagic acid, geranin, granatin B, corilagin), flavanoids, isovitexin,
vitexin, isoorientin, rutin and triterpenoiods (ursolic acid, 2α, 3β, 23-trihydroxyurs-12-en-28
oic acid) [10]. Tannin, a polyphenolic compound commonly found in most herbs, has antibacterial
properties. [11]
In aquaculture, The Indian almond leaves have been claimed as a promoting substance
for wound healing, especially for injured Siamese fighting fish after fighting matches. Chansue
et al. [12] reported increasing thickness of keratin layer in Siamese fighting fish scale. The leaves
have a potential to use as an alternative treatment for chemical substances and antibiotics.
Various concentrations of the extracts in water to prevent fish pathogen have been examined.
Chansue and Tangtrongpiros [13] found that water extracts of the dry leaves can rapidly promote
regeneration of fin tail of fancy carp. Chitmanat et al. [14] reported effectiveness of 0.8 mg/l
concentration of leaf extracts of Indian almond tree against Trichodina and other bacterial
infections in tilapia, and against fungal infection in tilapia egg. In addition, the leaf extracts can
eliminate Zoothamnium spp. infection of black tiger postlarva shrimp within 24 hours after
exposure [15], and can significantly decrease the number of Gyrodactylus and Dactylogyrus
infection of gold fish [16].
In Thailand, leaves of Indian almond tree have been widely used in Siamese fighting
fish culture as bath supplement for treating the injured fish and promoting the fish breeding.
However, the breeders still use their experiences to estimate the concentration of the leaves.
38 «“√“√—µ«·æ∑¬»“µ√å ¡¢. ªï∑’Ë 18 ©∫—∫∑’Ë 1 ¡°√“§¡ - ¡‘∂ÿπ“¬π 2551
Chansue [17] reported effects of the extract on hematology and blood chemistry of Siamese
fighting fish but not reported on its toxicity level. The objectives of this study were to evaluate
the antibacterial activity of the water extract of dried Indian almond leaves and to evaluate its
toxicity in ornamental fishes.
Materials and Methods
Collection of the leaves and preparation of the extract
Leaves of Indian almond tree were collected from some area in Bangkok, Thailand.
The leaves were dried in laboratory room at room temperature. To yield 50 mg/ml concentration,
1 kilogram of dried leaves was minced and soaked in 20 liters of distilled water for 1, 3, and
7 days at room temperature. The extracted solution was filtered (Whatman paper No. 4). Then,
various dilutions of the extract were prepared for optical density (OD) measurement by using
Spectrophotometer at 245 nm. wave length. Antibacterial activity and toxicity test were
determined by using the extract for 3 days.
Tannin analysis
Total tannin concentration was determined by Colorimetric method [18].
Antibacterial activity
Minimum Inhibitory Concentration (MIC) was done by the agar dilution technique.
The bacterial isolates used in this study were derived from fish and other aquatic animals from
the Veterinary Medicine Aquatic Reserch Center (VMARC), Chulalongkorn University,
Thailand. The isolates consisted of: Aeromonas hydrophila , A. sobria, Photobacterium damsela,
Pasteurella pneumotropica, Burkholderia cepacia, P. aeruginosa, P. oryzihabitans, Proteus valgaris,
Vibrio parahemolyticus, V. fluvialis, V. alginolytica, Shewanella putrefaciens, Stenotrophomonas
maltophilia, Klebsiella pneumoniae, and Enterococcus fecalis. The API-20E test (bioMerieux,
SA France) was used for bacterial identification.
A. hydrophila, A. sobria, P. aeruginosa, P. damsela, P. valgaris, E. fecalis and P.
pneumotropica were cultured on Mueller-Hinton agar plate. Other bacterial isolates were cultured
on Mueller-Hinton +1% NaCl agar plates. The bacterial suspension was diluted into 104 cfu/ml
(MacFarland nephelometer tube No. 0.5) and was spreaded on to the surface of agar medium
plates containing each concentration (5.0, 4.0, 3.5, 3.0, 2.5, 2.0, 1.5, 1.0, 0.8, 0.6, 0.4 and
0.2 mg/ml) of the 3 days extract. In the control plates, we used distilled water and 95% ethanol.
All samples were tested in triplicates.
KKU. Vet. J. Vol. 18 No. 1 JANUARY - JUNE 2008
Acute toxicity test of the extract
We used 3 species of ornamental fish including 210 guppy fish (Poecilia reticulate),
fancy carp (Cyprinus carpio), and Siamese fighting fish (Betta splendens) with average length of
2.0+0.21, 4.2±0.4 cm, 2.25±0.25, respectively. All fish, 30 fish of each type, were
acclimated for 14 days. Feed was given at 3% body weight twice daily. Static renewal system
was also applied daily.
Fifty percent lethal concentration (LC50)
The acute toxicity of the extract was observed in guppy, fancy carp, and Siamese fighting
fish. Concentrations (1.0, 2.0, 4.0, 6.0, 8.0, and 10 ppm) of the 3 days extract were tested
in 30 fish of each species in the 50 liter glass aquarium without any change of water for 96 hrs.
The water was continuously aerated. Mortality of fish was observed daily and the dead fish
were instantly removed.
Water quality analysis
Water quality parameters were measured in both the experimental and control groups.
The pH was determined by pH meter (Salinger & Mack). Alkalinity, hardness, ammonium, and
nitrite were determined by spectrophotometric kit (AQUA-VBC). Dissolved oxygen was
measured by Oxygen meter (YSI MODEL 57). Each parameter was determined in triplicates for
each group.
Statistical analysis
For warter parameters, the experimental data was calculated in the mean percentage of
each water parameter, compared with control groups. Differences between two means were
evaluated by the Studentûs t-test. For acute toxicity test, statistical analysis to determine median
lethal concentrations at 24, 48, 72, and 96 hrs used the binomial/nonlinear progression method,
nominal concentrations were used for the calculations [19].
The results showed that total tannin level increased when duration of extraction
increased. The total tannin levels of 1, 3, and 7 days extracts were 4.02, 13.60, and 14.08
mg/ml, respectively (Table 1.).
40 «“√“√—µ«·æ∑¬»“µ√å ¡¢. ªï∑’Ë 18 ©∫—∫∑’Ë 1 ¡°√“§¡ - ¡‘∂ÿπ“¬π 2551
MICs of the extracts ranged between 0.8-2.0 mg/ml (Table 2.). No growth inhibition was
observed in the control group. The liquid extractions showed higher effect against P. pneumotropica
(0.8 mg/ml), Photobacterium damsela and Enterococcus faecalis (1.0 mg/ml), and lower effect
against other bacterial organisms (1.5-2.0 mg/ml).
Table 1. Correlation of optical density (OD) and tannin level of the extract of dried Indian almond
leaves with various durations of extraction.
Duration of extraction OD Tannin
Control 0 0
1 day 0.045 4.02
3 days 0.211 13.60
7 days 0.243 14.08
Table 2. MICs (mg/ml) of the extract of dried Indian almond leaves.
Bacteria species VMARC MIC
Code (mg/ml)
Gram negative
Aeromonas hydrophila Ah001 1.5
Ah002 1.5
Ah003 2.0
Ah004 1.5
Aeromonas sobria As001 2.0
As002 2.0
Burkholderia cepacia Buc001 2.0
Pseudomonas aeruginosa Psa001 2.0
Pseudomonas oryzihabitans Pso001 2.0
Pasteurella pneumotropica Pap001 0.8
Photobacterium damsela Phd001 1.0
Phd002 1.5
Proteus valgaris Prv001 1.5
Shewanella putrefaciens Shp001 2.0
Stenotrophomonas maltophilia Stm001 2.0
KKU. Vet. J. Vol. 18 No. 1 JANUARY - JUNE 2008
Table 2. MICs (mg/ml) of the extract of dried Indian almond leaves. (Cont.)
Bacteria species VMARC MIC
Code (mg/ml)
Vibrio Parahemolyticus Vp001 2.0
Vibrio fluvialis Vf001 2.0
Vibrio alginolytica Va001 1.5
Gram positive
Enterococcus faecalis Enf001 1.0
Enf002 2.0
Klebsiella pneumoniae Klp001 2.0
When dried Indian almond leaves were extracted in water, the water gradually turned
brown, like tea color and generated acidic condition of the water as shown in Table 3. At the
concentrations of 0-4.0 mg/ml, the water pH of the extract was slightly lower (7.6-6.7) than
that of the control group, but pH of the extract at the concentrations of 6.0-10.0 mg/ml were
more acidic (pH 6.5-6.0) and significantly lower than that of control (p<0.05). The extract of
dried Indian almond leaves affects water quality by increasing ammonium ion level in the water.
Other parameter changes were not significantly different.
Table 3. Water parameters of various concentrations dried Indian almond leaves.
Conc. pH Alkalinity Hardness Ammonium Nitrite D.O.
(mg/ml) (ppm) (ppm) (ppm) (ppm) (ppm)
Control 7.60±0.14 60±2.5 180±10 0.00 0.000 4.28±0.36
1.0 7.52±0.13 60±0140±10 0.10±0.05 * 0.000 4.80±0.09
2.0 7.43±0.13 60±2.5 120±15 0.15±0.05 * 0.000 3.98±0.34
4.0 6.78±0.22 60±0160±10 0.15±0 * 0.000 4.78±0.03
6.0 6.52±0.14* 50±5.0 180±15 0.20±0 * 0.000 5.00±0.07
8.0 6.29±0.12* 50±5.0 140±15 0.15±0.05 * 0.000 4.80±0.07
10.0 6.09±0.16* 60±0160±10 0.10±0 * 0.000 4.42±0.37
* Value differs significantly (p<0.05) from value of control groups.
42 «“√“√—µ«·æ∑¬»“µ√å ¡¢. ªï∑’Ë 18 ©∫—∫∑’Ë 1 ¡°√“§¡ - ¡‘∂ÿπ“¬π 2551
Table 4. Mortality of guppy, fancy carp, and Siamese fighting fish exposed to the extract of dried
Indian almond leaves at LC50 values.
Fish LC50
24 h. 48 h. 72 h. 96 h.
Guppy (n=30) 6.2 5.4 5.8 5.6
Fancy carp (n=30) 7.6 7.0 5.9 5.8
Siamese fighting (n=30) 8.6 8.2 7.6 7.0
The extracts cause acute toxic to guppy, fancy carp, and Siamese fighting fish.
The toxicity of the extracts was shown in Table 4. There was no mortality in the control groups
(0 mg/ml). All fish showed similar clinical signs when initially exposed to all concentrations.
From observation, their rate of respiration increased according to faster opercula movement.
The survived fish returned to normal within 24 hrs. after treatment. Heavy solid suspension
adhered to the gills was observed during necropsy.
Discussion and Conclusion
Tannins possess antibacterial properties [11]. Tannic acid can inhibit the growth of
intestinal bacteria by binding with metal ions especially strong binding with iron and then forming
a chelate. The chelate, like a siderophore, is toxic to the membranes of microorganisms. When
tannins form chelating complex with iron in the medium, this action makes no iron available for
microorganisms to grow under aerobic condition. Bacterial growth was inhibited due in part to the
malfunction of the reduction of ribonucleotide precursor of DNA, formation of heme, and other
essential mechanisms [20]. According to this study, the total tannin level was rapidly increased
within the first 3 day of extraction then gradually increased. We can get higher concentration of
tannin when allowing longer time of extraction. However, the longer the time, the higher the
number of microorganisms contaminated [21]. Therefore, the extract of Indian almond leaves for
3 days was the most appropriate for use.
In this study, MICs of the extracts were ranged from 0.8-2.0 mg/ml. The extracts were
more effective against P. pneumotropica (0.8 mg/ml), Photobacterium damsela and
Enterococcus faecalis (1.0 mg/ml), but less effective against other bacterial organisms
(1.5-2.0 mg/ml). Chitmanat et al. [22] also reported that water solution of dried Indian almond
leaves (0.8 ppm) was able to inhibit A. hydrophila infection in tilapia.
KKU. Vet. J. Vol. 18 No. 1 JANUARY - JUNE 2008
The extracts are gradually acidic when their concentrations increase. Acceptable pH
for most fish cultures ranges from 6.2 to 7.8, but the rapidly change of pH over 0.2 may affect
the fish growth and can cause mortality [23]. The extracts also affect quality of water by
increasing level of ammonium ion in the water. Although ammonium ion (ionized ammonia) is
less toxic to fish than ammonia, increasing in ammonium ion may indicate increasing in ammonia.
Thus, balancing between ammonium ion and toxic ammonia should be determined by measuring
pH and temperature of the water [23].
Results from this study indicated that the extracts were toxic to any individuals
depending on the species of fish. Guppies were more sensitive than fancy carp and Siamese
fighting fish, respectively. Gills of the fish adhered with heavy solid suspension could be
observed when the fish underwent necropsy. This occurring might be another cause of death
because the adhered gills were blocked for oxygen and were irritated by high concentration
of tannins [24]. Tannic acid exhibits chelating properties when soaked in water, and can bind
cation in water to form colloid that possibly causes adhesion in fish gills [11]. Borisutpeth et al.
[25] reported that tannic acid caused hyperplasia of epithelial cells of gill filaments, fusion,
disarray, and aneurysm of gill lamellae, but no histopathological changes of other organs in
tilapia when the acid was used with concentration of 97.5 mg/ml for 96 hrs. However, in this
study, the treatment concentrations against aquatic bacteria (1.5-2.0 mg/ml) were much lower
than the lethal concentration. Therefore, Indian almond leaves can be developed for safer
treatment of bacterial infection in fish.
In conclusion, the water extracts of Indian almond leaves have potential to use as an
alternative of antibacterial agents and chemical substances. As natural products, the extracts may
overcome the problems of chemical residues and antibiotic resistances in fish cultures.
We would like to thank Assoc. Prof. Jirasak Tangtongpiros and Dr.Pansak
Assawawongkasem for advice. We thank also the staff of Veterinary Medical Aquatic Research
Center, Faculty of Veterinary Science for their kind assistance.
1. Whistler A. Polynesian Herbal Medicine. Hong Kong: Everbest Printing Co.,Ltd, 1992.
2. Zhai YF, Yao J, Fan YM, Xu LZ, Gao J, Zhao XN. Inhibitory effects of LR-98 on proliferation
of hepatocarcinoma cells. J Nanjing Univ (Natural Sciences). 2001;37(2):213-217.
44 «“√“√—µ«·æ∑¬»“µ√å ¡¢. ªï∑’Ë 18 ©∫—∫∑’Ë 1 ¡°√“§¡ - ¡‘∂ÿπ“¬π 2551
3. Masuda T, Yonemori Y, Oyama Y, Takeda T, Tanaka T. Evaluation of the antioxidant activity
of environmental plants: activity of the leaf extracts from seashore plants. J Agric Food Chem.
4. Tan GT, Pezzulo JM, Kinghom AD, Hughes SH. Evaluation of natural products as inhibitors
of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. J Nat Products.
5. Jing G, Huan D, Xin-Hui T, Li-Zhi X, Yi-Mei F, Xiao-Ning, Z. Inhibitory Effect of TCCE
on CCl4-induced Overexpression of IL-6 in Acute Liver Injury. ACTA. 2004;36(11):
6. Fan YM, Xu†LZ, Gao†J, Wang†Y, Tang†XH, Zhao†XN, et al. Phytochemical and antiinflammatory
studies on Terminalia catappa. Fitoterapia. 2004;75(3-4):253-260.†
7. Ratnasooriya WD, Dharmansiri MG. Effects of Terminalia catappa seeds on sexual behaviour
and fertility of male rats. Asian j. androl.†2000;2(3):213-219.
8. Goun E, Cunningham G, Chu D, Nguyen C, Miles D. Antibacterial and antifungal activity
of Indonesian ethnomedical plants. Fitoterapia. 2003;74(6):592-596.
9. Kloucek P, Polesny Z, Svobodova B, Vlkova E, Kokoska, L. Antibacterial screening of some
Peruvian medicinal plants used in Calleria District. J Ethnopharmacol. 2005;99(2):
10. Ahmed SM, Swamy V, Dhanapal PGR, Chandrashekara VM. Anti-Diabetic Activity of Terminalia
catappa Linn. Leaf Extracts in Alloxan-Induced Diabetic Rats. Iranian J Pharmacol &
Therapeutics. 2005;4(1): 36-39.
11. Chung KT, Lu Z, Chou MW. Mechanism of inhibition of tannic acid and related compounds
on the growth of intestinal bacteria. Food and Chemical Toxicology. 1998;36(12):
12. Chansue N, Mataderm T, Suilasuta A. 2004. Preliminary study of Effects of Dried Indian
Almond Terminalia catappa leaf on ultrastuctural morphology of scale in Siamese Fighting
Fish (Betta splendens). Proceeding of Thai Herbal: Opportunities and Alternative way for
Agriculture-Animal industries. Siam city Hotel. Bangkok, Thailand, January 15-16 (2004).
13. Chansue N, Tangtrongpiros J. Efficacies of dry Indian almond leaf (Terminalia catappa) and
Andrographis paniculata (Burm. F) Wall. Ex Nees Extract on tail regeneration and Hematocrit
of Fancy Carp (Cyprinus carpio Linn.). J Thai Vet Med Assoc. 2006;57(2):52-62.
KKU. Vet. J. Vol. 18 No. 1 JANUARY - JUNE 2008
14. Chitmanat C, Tongdonmuan K, Nunsong W. The use of crude extract from traditional
medicinal plants to eliminate Tricodina sp. In tilapia (Oreochromis niliticus) fingerlings.
Songklanakarin J. Sci. Technol. 2005;27(Suppl.1):359-364.
15. Watchariya P, Surapon W. Nontawit A. 2004. Efficiency of some Herbals for eliminate
Zoothamnium sp. and toxicity on Penaeus monodon Fabricius. The 5th National conference
of marine shrimp. Miracle Grand Convention Hotel. Bangkok. BIOTEC. March 29-30, 2004
16. Chansue N, Tangtrongpiros J. 2005. Effect of Dried Indian almond Leaf (Terminalia catappa)
on Monogenean Parasite of Gold Fish (Carassius auratus). Proceeding of the 4th
Chulalongkorn University Veterinary Annual Conference. 60 Veterinary Anniversary Building,
Chulalongkorn University, Faculty of Veterinary Science, Bangkok, Thailand, February 15
(2005), 55-56.
17. Chansue N . 2003 . Effects of Dried Indian Almond Terminalia catappa leaf on Hematology
and Blood chemistry of Siamese Fighting Fish (Betta splendens). Proceeding of Quality:
The Focus of Asian Aquaculture. Bangkok, Thailand. Sepember 22-25 (2003). 77.
18. AOAC. Official Method of Analysis. Association of Official Analytical Chemists† 15th.
edition Washington, DC. USA. 1990;66-88.
19. Steel RGD, Tories JH, Dickey DA. Principles and Procedures of Statistics: A Biometric
Approach. Singapore: McGraw-Hill. 1997.
20. Scalbert A. Antimicrobial properties of tannins. Phytochem. 1991;12:3875-3883.
21. Intranupakorn R. Herb Inspections and extractions of Active Ingredients. Bangkok:
Chulalongkorn University Press. 2004.
22. Chitmanat C, Tongdonmuan K, Khanom P, Pachontis P, Nunsong W. Antiparasitic,
antibacterial, and antifungal activities derived from a Terminalia catappa solution against
some tilapia (Oreochromis niliticus) pathogen. Acta Hort. (ISHS) 2005;678:79-182.
23. Boyd CE. Water Quality in ponds for Aquaculture. Principles of water quality. Thailand:
Shrimp Mart (Thai) Co. Ltd. 1990. p. 46-47.
24. Treves-Brown KM. Externally applied antimicrobial agents. Applied fish Pharmacology.
Netherlands: Kluwer Academic Publishers. 2000. p.164-171.
25. Borisutpeth P, Hanjavanij C, Luangpirom A, Lawhavinit O. Acute effect of tannic acid on
intestine, liver and kidney of Oreochromis niloticus (L.). KKU Sci J. 2001;31(3):157-166.
A nanocomposite based on silver nanoparticles (AgNPs) and extract of Terminalia catappa was developed, characterized, and evaluated in in vitro and in vivo conditions against Saprolegnia parasitica infection. The nanocomposite contained spheroidal silver-nanoparticles (1–55 nm) and presented active compounds as gallic acid, ellagic acid, and α and β punicalagin. The nanoparticles remained stable for one year after its production. A synergistic effect was observed between AgNPs and extract under in vitro and in vivo conditions against different stages of fungal development. In an in vitro assay, the nanocomposite showed fungistatic and fungicide effects to the fungal mycelium in solid and liquid media, respectively, through an increase in the contact surface. In an in vivo bioassay, the lowest concentration of nanocomposite (T1 = 45.75 μg.L⁻¹ AgNPs +62.5 μg.L⁻¹ T. catappa extract) demonstrated similar efficiency as the positive control (methylene blue) in preventing zoospore infectivity in eggs of angelfish (Pterophyllum scalare). The fungal zoospores were more sensitive to the nanocomposite than fungal mycelia. Our results exhibited the use of a nanocomposite containing AgNPs and T. catappa aqueous extract could reduce the required effective concentrations of AgNPs against saprolegniosis in fish eggs, thus, it may as an alternative to improve fish larval survival at the hatchery stage.
Differential responses of Vibrio sp. to young and mature leaves extracts of Terminalia catappa L. Abstract Young and mature leaves of Terminalia catappa of alcoholic and aqueous extracts were evaluated for in vitro antibacterial activity against Vibrio sp. isolated from aquatic animals. Young leaves of T. catappa showed higher antibacterial activity when compared to mature leaves against Vibrio parahemolyticus, with methanolic and aqueous extracts exhibited the largest inhibition zones, 23 and 24 mm, respectively as determined by disc diffusion technique. Ethanolic extract of young leaves showed the lowest MIC and MBC at 3.13 mg/ml and 6.25 mg/ml, respectively. Both alcoholic and aqueous extracts of young and matures leaves exhibit variations in protein, RNA as well as pyrine and pyrimidines leakage of Vibrio sp. Cell membrane disruption is proposed as the mechanism of action of T. catappa leaves extract against Vibrio sp.
Full-text available
This book is aimed at ethnobotany students, doctors studying herbal medicines, and anyone else who wants to learn something about Polynesian cultures and their herbal medicine heritage. The presence of color photos will greatly assist those wanting to identify the medicinal plants, particularly those species discussed in the other books produced by Isle Botanica, such as Tongan Herbal Medicine and Samoan Herbal Medicine. The book is not meant to be used as a practical guide for someone taking or administering medicine, since the information was collected with the understanding of the healers that it was not for this purpose, and dosage is consequently not given. The use of medicinal plants dates to prehistoric times when ancient people found that ingestion or application of certain herbs and barks was effective in treating some of the ailments that plagued them. Herbal medicine is a part of virtually all cultures, and the South Pacific islands that comprise Polynesian are no exception. Even today herbal medicine is used at one time or another by a large percentage of the Polynesians living in Samoa, Tonga, the Cook Islands, the Society Islands, Hawai'i, and New Zealand, especially during infancy and childhood. While plants used for food, shelter, dyes, and many others aspects of the material culture of Tonga are easy to see and study, the use of plants for medicines is more esoteric. To elucidate this poorly known facet of Polynesian culture, the author undertook a study of Polynesian herbal medicine, which involved interviews with over 75 local healers over a several-year span. The book is divided into four chapters. The first, "Introduction to Polynesia," includes sections on the islands, the people, the languages, and the migrations. The second chapter, "Traditional Polynesian Medical Practices," includes sections on the applicable literature, the ailments of the ancient Polynesians, the epidemics, the causation of illness, medical practices, the treatment of injuries, Polynesian massage, and a summary. The third chapter, "Polynesian Medical Practices Today," includes a discussion of current medicinal practices in five parts of Polynesia - Tonga, Samoa, Tahiti, the Cook Islands, and Hawaii. The fourth chapter, "The Medicinal Plants," comprises an enumeration and discussion of 90 of the most commonly used medicinal plants in Polynesia. These are arranged in alphabetical order by scientific name. Each species has a detailed, close-up color photo and the following information: (1) scientific name; (2) family to which the plant belongs; (3) English name or names (if any); (4) Polynesian names in Samoa, Tonga, the Cook Islands, the Society Islands, and Hawaii; (5) a botanical description (6) distribution; (7) habitat in which the plant is found; and (8) uses, both medicinal and non-medicinal, in Polynesia and elsewhere in the world. Following the four chapters is a bibliography of pertinent literature, an index to the scientific names, and an index to Polynesian names.
Full-text available
Tilapia, Oreochromis niloticus, is one of the most economically important fishery products of Thailand with export viability. Unfortunately, disease losses cause a major problem in the production of farmed tilapia. Most farmers have been using chemicals and antibiotics to treat fish pathogens which leads to the creation of antibiotic resistant pathogens and undesired residues in the fish and in the environment. Food safety is currently a great concern worldwide and Thailand's inspectors are now finding antibiotic residues in exported fish products. The purpose of the present research is to apply the Indian almond, Terminalia catappa, as an alternative to the use of chemicals and antibiotics in the aquaculture industry. Dried leaves of Indian almond were ground and dissolved in water. A variety of concentrations of this solution were used to determine resulting activities against tilapia pathogens. The results indicated that Trichodina, fish ectoparasites, were eradicated at 800 ppm. The growth of two strains of Aeromonas hydrophila was also inhibited at a concentration of 0.5 mg/ml Indian almond leaves upward. In addition, this solution can reduce the fungal infection in tilapia eggs. Research is underway to determine the toxicity of this solution, if any, on tilapia and the isolation of the active ingredients in the Indian almond for fish pathogen treatment.
Aim: To evaluate the aphrodisiac potential of Terminalia catappa Linn. seeds using a suspension of its kernel (SS) in 1% methyl cellulose in rats. Methods: Male rats were orally treated with 1500 mg/kg or 3000 mg/kg SS or vehicle, and their sexual behaviour was monitored 3 h later using a receptive female. Another group of rats was orally treated with either 3000 mg/kg SS or vehicle for 7 consecutive days. Their sexual behaviour and fertility were evaluated on days 1, 4 and 7 of treatment and day 7 post-treatment by pairing overnight with a pro-oestrous female. Results: The 1500 mg/kg dose, had a marked aphrodisiac action (prolongation of ejaculation latency) but no effect on libido (% mounting, % intromission and % ejaculation), sexual vigour (mounting-and-intromission frequency), or sexual performance (intercopulatory interval). In contrast, the higher dose (3000 mg/kg) reversibly inhibited all the parameters of sexual behaviour other than mounting-and-intromission frequency and copulatory efficiency. The effects of high dose SS were not due to general toxicity, liver toxicity, haemotoxicity, stress, muscle deficiency, muscle incoordination, analgesia, hypoglycaemia or reduction in blood testosterone level. They were due to marked sedation. Conclusion: The kernel of T. catappa seeds has aphrodisiac activity and may be useful in the treatment of certain forms of sexual inadequacies, such as premature ejaculation.
Formalin is a very widely used anti-parasitic agent. It is used routinely against many protozoans parasitic on the skin or gills of fish, including Chilodonella spp., Epistylis spp., Ichthyobodo (Costia) necator, Ichthyophthirius multifiliis, Scyphidia spp. and Trichodina spp. It has little activity against a majority of bacteria but has been used for bacterial gill disease which is a mixed infection caused by Flavobacterium branchiophilum together with protozoans. It is also useful for the monogenetic fluke parasites of fish gills and skin, respectively Dactylogyrus and Gyrodactylus spp., and also Cleidodiscus spp.
Goldfish (Carassius auratus), a popular ornamental fish, is often affected by external parasites such as Gyrodactylus sp. and Dactylogyrus sp. The effects of Indian almond leaf (IAL) extract on the elimination of these parasites were investigated. The highest applied concentration of IAL (5.1 g/l of water) was the most effective, completely eliminating all parasites after 2 weeks of treatment without adverse side effects. A concentration of 3.4 g/l eliminated all Dactylogyrus sp. and virtually all Gyrodactylus sp. after 3 weeks of treatment, whereas some parasites still persisted after 4 weeks of treatment with 1.7 g/l. No significant reduction of parasites occurred in the control group without treatment.
Inhibition of human immunodeficiency virus reverse transcriptase is currently considered a useful approach in the prophylaxis and intervention of acquired immunodeficiency syndrome (AIDS), and natural products have not been extensively explored as inhibitors of this enzyme. We currently report that the reverse transcriptase assay developed for the detection of the enzyme in virions involving polyadenylic acid.oligodeoxythymidylic acid (poly rA.oligo dT) and radiolabeled thymidine 5'-triphosphate (TTP), can be applied as a simple method for screening the human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) inhibitory potential of natural products. As reported herein, 156 pure natural products have been examined in this system. Benzophenanthridine alkaloids such as fagaronine chloride [1] and nitidine chloride, which are known inhibitors of avian myeloblastosis virus reverse transcriptase, demonstrated potent activity in the HIV-1 RT system, and 1 (IC50 10-mu-g/ml) was adopted as a positive-control substance. Additional inhibitors found were columbamine iodide [2] and other protoberberine alkaloids, the isoquinoline alkaloid O-methylpsychotrine sulfate [3], and the iridoid fulvoplumierin [4]. A number of indolizidine, pyrrolizidine, quinolizidine, indole, and other alkaloids, as well as compounds of many other structural classes, were tested and found to be inactive. A total of 100 plant extracts have also been evaluated, and 15 of these extracts showed significant inhibitory activity. Because tannins and other polyphenolic compounds are potent reverse transcriptase inhibitors, methods were evaluated for the removal of these from plant extracts prior to testing. Polyphenolic compounds were found to be responsible for the activity demonstrated by the majority of plant extracts. After appropriate tannin removal procedures were established, the bioassay system was shown to be generally applicable to both pure natural products and plant extracts. The method also proved useful in directing an isolation procedure with Plumeria rubra to yield fulvoplumierin [4] as an active compound (IC50 45-mu-g/ml).
Tannin toxicity for fungi, bacteria and yeasts is reviewed and compared to toxicity of related lower molecular weight phenols. The dependence of toxicity on tannin structure is examined. The different mechanisms proposed so far to explain tannin antimicrobial activity include inhibition of extracellular microbial enzymes, deprivation of the substrates required for microbial growth or direct action on microbial metabolism through inhibition of oxidative phosphorylation. A further mechanism involving iron deprivation is proposed. Many microorganisms can overcome plant defences based on tannins. They may detoxify tannins through synthesis of tannin- complexing polymers, oxidation, tannin biodegradation or synthesis of siderophores.
In view of suggested anti diabetic potential, effect of aqueous and cold extracts of Terminalia Catappa Linn (Combretaceae) leaves, on fasting blood sugar levels and serum biochemical analysis in alloxaninduced diabetic rats was investigated. All the extracts of Terminalia Catappa produced a significant anti diabetic activity at dose levels of 1/5th of their lethal doses. Concurrent histological studies of the pancreas of these animals showed regeneration by aqueous and cold extracts which were earlier necrosed by alloxan.
The treatment for ectoparasitic diseases in freshwater fish with formalin seems at present to be ineffective. For this reason it is evidently a useless cost. In addition, formalin possibly leaves toxic residues in fish flesh and in the environment which are eventually harmful to consumers. The alternative way to solve this problem is to use traditional medicinal plants instead. The purpose of this research is to determine the possibility of using garlic (Allium sativum) and Indian almond (Terminalia catappa) as optional chemicals to treat fish ectoparasites, Trichodina sp. The results showed that crude extracts of either garlic or Indian almond at 800 mg/l significantly (P < 0.05) eliminated Trichodina sp. infections in tilapia (average weight 3.62±0.06 g each). To evaluate the acute toxicity of these products to the host fish, groups of 20 tilapia (same size as above)were exposed to 3 concentrations of each product for 96 h. Mortality was then determined. The 2 h LC50 for tilapia exposed to crude extract of garlic was 2,259.44 mg/L while the 16 h LC50 for tilapia exposed to Indian almond extract was 46,665.94 mg/L. This information is the beneficial and fundamental knowledge to develop guidelines to reduce the use of chemicals and antibiotics in freshwater fish culture businesses. The research is underway to determine the long-term effect of Indian almond and garlic to tilapia, if any.