Gen info
- Etymology: Specific epithet acuminatissimum derives from Latin, meaning "very pointed", referring to the leaf tip.

Botany
• Trees, to 20 m tall. Branchlets terete or obtusely ridged. Petiole 5-8 mm; leaf blade ovate-lanceolate to narrowly lanceolate, 5-12 × 1-3.5 cm, leathery, adaxially dark with numerous oil glands, secondary veins numerous, ca. 3 mm apart, at an angle of 65°-70° from midvein, abaxially visible, and adaxially inconspicuous, intramarginal veins ca. 1.5 mm from margin, base broadly cuneate, apex caudate-acuminate and with a ca. 2 cm acumen. Inflorescences terminal, 3-flowered cymes arranged into panicles, 3-6 cm; peduncle ridged. Flower buds obovoid, 3-4 mm, basally cuneate, apically rounded. Hypanthium obconic, shortly stipitate. Calyx lobes inconspicuous, apical margins of hypanthium incurved. Petals white, distinct, ca. 1 mm. Stamens ca. 1 mm. Fruit blackish purple when ripe, globose, ca. 1.5 cm in diam., 1-seeded. Embryo with intrusive branching tissue extending into and interlocking cotyledons. (Flora of China)

• Small canopy tree, 20(-34) m tall, 54 cm diameter, with small buttresses and often stilt roots, pale brown smooth to patchily thinly flaky bark and pink-brown inner bark. Parts hairless. Twig 2-3 mm diameter, round or slightly quadrangular towards apex, pale brown, smooth. Leaves often subopposite; blade c.9 x 4 (3.5-13 x 1.5-4) cm, elliptic to occasionally lanceolate, thinly leathery, drying dull pale brown; base narrowly wedge-shaped tapering into c.8 mm slender stalk, acumen c.2 cm long, slender; sparsely minutely pitted above, without dots beneath; veins unequal, c.12 pairs, distinctly raised more so beneath but slender, hardly or not furrowed above, ascending; tertiaries visible throughout; intramarginal veins close to margin, hardly looped. Panicle 3-terminal or subterminal axillary, 6 cm long, slender, 2-3-branched. Flowers bunched on the branchlets; bud 5x3 mm, club-shaped with 3 mm slender pseudostalk; sepal lobes 4, broadly hemispherical, cupped, deciduous; stamens many, extruded c.4 mm with style, anthers subglobose or broader than long, spreading from the base, end-porous. Fruit c.15 mm diameter, often misshapen, with minute raised sepal-rim, ripening pinkish to purple. (Tree Flora of Sabah and Sarawak) (2)

Distribution
- Native to the Philippines.
- Common in primary forests at low and medium altitude.
- Also native to Andaman Is., Assam, Bismarck Archipelago, Borneo, China Southeast, Hainan, Jawa, Laos, Lesser Sunda Is., Malaya, Myanmar, New Guinea, Solomon Is., Sulawesi, Sumatera, Taiwan, Thailand, Vietnam. (1)

Constituents
- GC-FID/MS analysis of fresh leaves of Syzygium acuminatissimum for essential oil yielded 0.16% EO with 44 compounds representing 95.7% of the composition. Sesquiterpene hydrocarbons (54.5%) and their oxygenated derivatives (31.6%) were two main chemical classes, along with oxygenated monoterpenes (9.0%), monoterpene hydrocarbons (0.3%), and non-terpenes (0.3%). Major compound included caryophyllene oxide (18.9%), (E)-caryophyllene (9.9%), α-copaene (9.2%), α-cadinene (9.1%), and 1,8-cineole (5.3%). (see study below) (4)
- GC analysis of fruit essential oil yileded 50 compounds (96.9%) of composition, with sesquiterpene hydrocarbons (51.6%) and oxygenated derivatives (23.5%) as two main classes, along with oxygenated monoterpenes (4.9%) and non-terpenic compounds (0.3%).   The EO was dominated by (E)-caryophyllene (14.2%), α-pinene (12.1%), caryophyllene oxide (10.9%), ß-selinene (10.8%), α-selinene (8.0%) and α-humulene (5.7%). (see study below) (4)

Properties
- Studies have suggested antibacterial, mosquito larvicidal properties.

Parts used
Fruits and leaves.

Uses
Edibility
- Fruits is edible.
Folkloric
- No reported folkloric medicinal usage in the Philippines.
Others
- Wood: Moderately hard; somewhat durable, moderately resistant to fungi and termites, but susceptible to dry wood borers. Suitable for making musical instruments, tool handles, furniture components, ship building, house post fn framing, carpentry, joinery, flooring. (3)

Studies
• Antibacterial / Larvicidal / Essential Oil / Leaves and Fruits: Study evaluated five Vietnamese Syzygium species for essential oil components, and antimicrobial and mosquito larvicidal activities. S. acuminatissimum fruit essential oil exhibited antibacterial activity against E. faecalis and B. cereus with MIC of 8 µg/mL, which were muct better than positive control streptomycin (MIC 128-256 µg/mL). The essential oil also exhibited mosquito larvicidal activity against Cx quinquefasciatus and Ae. aegypti. (see constituents above) (4)

Availability
Wild-crafted.

Additional Sources and Suggested Readings
(1)
Syzygium acuminatissimum / Synonyms / KEW: Plants of the World Online
(2)
Syzygium acuminatissimum / AsianPlantNet
(3)
Syzygium acuminatissimum / Ken Fern: Tropical Plants Database / Useful Tropical Plants
(4)
Essential Oils of Five Syzygium Species Growing Wild in Vietnam: Chemical Compositions and Antimicrobial and Mosquito Larvicidal Potentials / Le Thi Huong, Nguyen Huy Hung, Nguyen Ngoc Linh, Ty Viet Pham, Do Ngoc Dai et al /  Molecules, 2023; 28(22): 7505 / DOI: 10.3390/molecules28227505
(5)
SR:Macronutrients Uptake of Lahi-Lahi (Syzygium Acuminatissimum, Blume) Nursery Seedlings as Mediated by Biofertilizers in Heavy Metal Contaminated Mined-Out Soils in Surigao Del Norte, Philippines / Mitz Campugan Tapi-on, Nelly S Aggangan et al / SSRN

DOI: It is not uncommon for links on studies/sources to change. Copying and pasting the information on the search window or using the DOI (if available) will often redirect to the new link page. (Citing and Using a (DOI) Digital Object Identifier)