- Bruguiera is a plant genus in the family Rhizophoraceae -- a small genus of five mangrove species and three hybrids.
Etymology: The genus name honors Jean Guillaume Bruguiere (1750-1799), a French biologist and explorer. The species name derives from Latin "cylindrica", referring to the shape of the propagule of this species.
- B. cylindrica grows under very harsh conditions and known as the slowest-growing commercially used tree species in Malaysia.
Bruguiera cylindrica is a small tree growing 10-15 m tall. Bark is gray, smooth, with few corky raised lenticels. Aerial roots or pneumatophores project from the soil in knee-shaped loops. Stipules 2.5-3.5 cm. Petiole 1-3.5 cm; leaf blade elliptic, 7-17 by 2-8 cm, thin, secondary veins abaxially remote and thin, reticulate veins mostly obscure, base cuneate, apex acute. Cymes pedunculate, 2- or 3-flowered. Pedicel 1-4 mm. Flowers greenish, less than 2 cm. Calyx tube 4-6 by ca. 2 mm, not ribbed, smooth; lobes 7 or 8, about as long as the tube. Petals white but soon turning brown, 3-4 mm, 2-lobed, outer margins usually basally fringed with white hairs. Stamens 1.5-2.5 mm. Disk in open flowers not entirely lining calyx tube. Style 3-4 mm. Fruiting calyx tube ca. 1 cm, slightly ribbed; lobes recurved. Hypocotyl cylindric, often curved, 8-15 by ca. 0.5 cm. (Flora of China) (2)
Tree up to 23 m by 20-30 cm. Leaves thin, elliptic, 7-17 by 2-8 cm, acute, base cuneate; petiole 1-4.5 cm. Stipules 2.5-3.5 cm long. Pedicels 1-4 mm. Flowers greenish, 10-12 mm long. Calyx tube smooth, 4-6 by 2 mm, lobes 8, about as long as the tube. Petals 3-4 mm long, outer margins usually fringed with white hairs at the lower part. Stamens 1.5-2.5 mm. Hypocotyl cylindrical, often curved, 8-15 by 0.5 cm. (eFlora of Thailand) (2)
- Native to the Philippines.
- Also native to Andaman Is., Bangladesh, Bismark Archipelago, Borneo, Cambodia, Hainan, India, Jawa, Laccadive Is., Lesser Sunda Is., Malaya, Maldives, Maluku, Myanmar, New Guinea, Queensland, Sri Lanka, Sulawesi, Sumatera, Thailand, Vietnam.
- In Malaysia, it occupies the highest parts of the mangrove forest along the seacoast where flooding is only occasional, up to 20 m above sea level. (4)
- GC-MS and UHPLC-Q-Exative Orbitrap HRMS metabolic profiling of ethyl acetate extract of Bruguiera cylindrica leaves yielded 36 compounds belonging to different classes of secondary metabolites viz. flavonoids, fatty acids, fatty acid amides, carboxylic acids, and alkaloids. Pentacyclic triterpenes like betulin, ursolic acid and atropine, an alkaloids with potential pharmacological and therapeutic activities such as anticancer properties, neuromuscular blockers and antioxidants, were also identified. (9)
- Study of fruits isolated six new pentacyclic triterpenoid esters (1-6) together with 3α- and 3ß-taraxerol. Structure of the new compounds were characterized as 3α-E-feruloyltaraxerol (1), 3α-Z-feruloyltaraxerol (2), 3ß-E-feruloyltaraxerol (3), 3ß-Z-feruloyltaraxerol (4), 3α-E-coumaroyltaraxerol (5), and 3α-Z-coumaroyltaraxerol. (see study below) (13)
- Phytochemical screening yielded flavonoids, saponins, tannins, and terpenoids, with absence of alkaloids, glycosides, phenols, and steroids.
- Phytochemical screening of crude methanolic extract of leaves yielded carbohydrates, glycosides, phenol, tannin protein, gum and mucilages. (see study below)
- Study isolated three new pentacyclic triterpenoid esters 1-3 along with six known lupane-type triterpenoids. Structures of the new compounds were elucidated and characterized as 3α-E-coumaroyl-lupeol (1), 3α-Z-coumaroyllupeol (2) and 3α-E-caffeoyltaraxerol (3).
Studies have suggested antioxidant, antibacterial, antidiabetic, antiviral, α-glucosidase inhibitory, anticancer, AChE inhibitory, thrombolytic, membrane stabilizing, mosquitocidal properties.
Bark, leaves, twigs, fruits.
- Young hypocotyls are edible; boiled and eaten as vegetable or preserve, usually in times of famine.
- Young radicles occasionally eaten with sugar and coconut. Young shoots eaten as salad.
- Bark is a source of spice.
- No found folkloric medicinal use in the Philippines.
-- Bark used to stop hemorrhage and applied to malignant ulcers.
- Plant parts used in Chinese and Indian Medicine for treatment of diarrhea, fever, and many other ailments.
- In Thailand, used for wound healing and to treat diarrhea.
- Leaves used to lower blood pressure.
- Wood: Timber is dense, reddish, and strong. Used for light construction, for parts of the hull and keel of canoes. The crushed bark has an unusual odor that is repulsive to fish, for which it is avoided for use as fish traps. (21)
- Fuel: Used for firewood, and charcoal.
Perfume: Extracts made from pneumatophores are used in the manufacture of perfume. (21)
• Antioxidant: Study evaluated the antioxidant activities of two Indian mangrove plants, Bruguiera cylindrica and Ceriops decandra. Bruguiera cylindrica yielded 233.3 ± 0.062 mg gallic acid equivalent/g phenolic contents and 11.6 ± 0.12 mg quercetin equivalent/g flavonoid content. The extracts exhibited high antiradical activity against DPPH, ABTS, and OH radical. Reductive capacity increased with increasing concentration. Extract also inhibited H2O2 induced hemolysis in cow blood erythrocytes. Antioxidant activity was stronger than reference butylated hydroxy toluene (BHT). The plant can be considered a good source of natural antioxidants. (5)
• Antibacterial / Leaves / Twigs: Mangroves are potential natural antibacterial sources. Study evaluated the antibacterial activity of wet and dried leaf extracts of B. cylindrica. The ethanol extract showed to be the best solvent for phenolic and flavonoid extraction. The widest zone of inhibition was shown by wet extracts against S. aureus and E. coli at 14.3 and 13.3 mm, respectively. (6) Study evaluated dried samples of bark, leaf pod and twig of B. cylindrica macerated with methanol. Crude extract of each part was screened for antibacterial activity against aquatic pathogenic bacteria. Most plant extracts showed a wide range of antibacterial activity against gram-positive and gram-negative bacteria. The leaf and twig extracts showed lowest MIC/MBC to S. agalactiae. Activity was attributed to terpenoids from the leaf and twig. (12) In a study of Bruguiera leaf extract for antimicrobial activity, an ethanol extract showed highest diameter of zone of inhibition against Staphylococcus aureus with 14.30 mm and against E. coli with 13.30 mm. (19)
• Antidiabetic / Leaves: Study evaluated effect of ethanolic extract of B. cylindrica leaves on the rate of glucose transport across cell membrane in yeast cells system. The increase of percentage of glucose uptake by yeast cells was found in glucose concentrations varying from 5 to 25 mM in the presence of 1 and 5 mg/ml of B. cylindrica ethanolic extract. Results suggest BCEE has potential as a therapeutic agent and as source of novel bioactive compounds for treatment of T2DM. (7)
• Silver Nanoparticles against Dengue Virus DEN-2 and Mosquito Ae. aegypti: Study reports on the biosynthesis of antiviral and mosquitocidal silver nanoparticles using aqueous extract of B. cylindrica leaves. The aqueous extract and green-synthesized NPs were tested against primary dengue vector Aedes aegypti. The AgNOs were the most effective with LC50 range of 8.93 ppm (larva I) to 30.69 ppm (pupa). In vitro, 30 µg/ml of AgNOs significantly inhibited the production of dengue viral envelope (E) protein in vero cells and downregulated the expression of dengue viral E gene. Results highlight the potential of the AgNPs against dengue virus. The AgNPs can be employed at low doses to reduce larval and pupal population of Ae. aegypti without detrimental effects of predation rates of mosquito predators, such as C. auratus. (8)
• α-Glucosidase Inhibitory Activity / Leaves: Study evaluated the α-glucosidase inhibitory activity of B. cylindrica, along with constituents of ethyl acetate extract of the plant. Two new compounds, benzobrugierol (1) and bruguierine (2) were isolated from the leaves, along with nine other compounds. The extracts and some isolated compounds were evaluated for α-glucosidase inhibitory activities. Results showed most of the extracts and tested compounds exhibited better activities than positive control acarbose, especially the two new compounds (1 and 2) with IC50s of 17.9 ± 0.4 and 34.6 ± 0.7 mg/mL, respectively. (10)
• Antiviral Activity from Mangrove Halophytes / Leaves: Study evaluated extracts of different portions of mangroves in vitro against four RNA viruses viz., New Castle disease virus, encephalomyocarditis virus, Semliki forest virus and human immunodeficiency virus and two DNA viruses - vaccinia virus and hepatitis B. A broad spectrum antiviral activity was exhibited in the leaves of Bruguiera cylindrica and bark of Rhizophora mucronata. (11) Of 73 extracts examined, 43 exhibited antiviral activity (>50%) against at least any one of the viruses. Only two extracts, leaf of B. cylindrica and bark of Rhizophora mucronata showed activity against all viruses tested.
• Pentacyclic Triterpenoid Esters / Cytotoxicity / Fruits: Study of fruits isolated six new pentacyclic triterpenoid esters (1-6). Compounds 2 and 6 ( 3ß-E-feruloyltaraxerol and 3α-Z-coumaroyltaraxerol) exhibited weak cytotoxicity against the NCI-H187 cell line. (see constituents above) (13)
• AChE Inhibitory Potential / Taraxerol Esters / Leaves: Systematic chemical screening of leaves yielded five single and pure compounds: taraxerol (1), 3ß-(E)-coumaroyltaraxerol (2), 3ß-(Z)-coumaroyltaraxerol (3), ß-sitosterol (4), and eicosanol (5). From compound1, taraxerol, ten cinnamyl esters were synthesized in very good excellent yields. Compound 9 showed promising AChE inhibition with significantly low IC50 values, low cytotoxicity, and high BBB permeability. Results suggest compound 9 can be a lead molecule for the development of a potent AChE inhibitor. (14)
• Thrombolytic / Membrane Stabilizing / Cytotoxicity / Leaves: Study evaluated the in vitro thrombolytic, membrane stabilizing and cytotoxic activities of crude methanolic extracts of B. cylindrica leaves, which was cleaned, dried, and ground to a powdery mass. Extract at 10 mg/ml concentration showed moderate clot lysis (14.51 — 1.87%) while standard streptokinase showed 59.73 ± 0.97% clot lysis. Extracts also exhibited significant anti-inflammatory properties at 10 mg/ml by both hypotonic solution and heat induced hemolysis of erythrocyte membrane. Cytotoxicity by Brine shrimp lethality bioassay showed moderate cytotoxic properties with LC50 of 16.628. (16)
• Chemoprevention of Gastric Cancer / Leaves: Study evaluated the effects of B. cylindrica leaves extract on anti-gastric cancer activities of Benzo(a) pyrene (BaP)-induced gastric cancer in albino mice. Tumor incidence was 100% in mice that received only B(a)P. Administration of B. cylindrica significantly reduced the incidence of stomach tumors, modulated lipid peroxidation and enhanced antioxidant status in the stomach, liver, and blood, which may all contribute to its chemopreventive effect. (18)