The volatile constituents of three different clones of durian (Durio zibethinus Murr.) were isolated by vacuum distillation with subsequent extraction of the distillates with dichloromethane. The concentrated extracts were analysed by capillary GC and GC-MS. A total of 63 constituents were identified, comprising 30 esters, 16 sulphurcontaining compounds, 5 ketones, 8 alcohols and 4 miscellaneous compounds. All three clones produced approximately the same proportions of esters and of ketones. The first-mentioned chemical class was quantitatively the most important among durian volatiles. There was much variation in the content of sulphur volatiles among the three clones. Identified among this chemical class were some uncommon plant volatiles such as cis-and trans-3,5-dimethyl-1,2,4-trithiolane and S-alkyl esters of alkylthiocarboxylic acids.

The aqueous methanolic extracts of Melastoma malabathricum L. exhibited antibacterial activity when assayed against seven microorganisms by the agar diffusion method. Solvent fractionation afforded active chloroform and ethyl acetate fractions from the leaves and the flowers, respectively. A phytochemical study resulted in the identification of ursolic acid (1), 2α-hydroxyursolic acid (2), asiatic acid (3), β-sitosterol 3-O-β-D-glucopyranoside (4) and the glycolipid glycerol 1,2-dilinolenyl-3-O-β-D-galactopyanoside (5) from the chloroform fraction. Kaempferol (6), kaempferol 3-O-α-L-rhamnopyranoside (7), kaempferol 3-O-β-D-glucopyranoside (8), kaempferol 3-O-β-D-galactopyranoside (9), kaempferol 3-O-(2″,6″-di-O-E-p-coumaryl)-β-D-galactopyranoside (10), quercetin (11) and ellagic acid (12) were found in the ethyl acetate fraction. The structures of these compounds were determined by chemical and spectral analyses. Compounds 1-4, the flavonols (6 and 11) and ellagic acid (12) were found to be active against some of the tested microorganisms, while the kaempferol 3-O-glycosides (7-9) did not show any activity, indicating the role of the free 3-OH for antibacterial activity. Addition of p-coumaryl groups results in mild activity for 10 against Staphylococcus aureus and Bacillus cereus. Compounds 2-5, 7 and 9-12 are reported for the first time from M. malabathricum. Compound 10 is rare, being reported only once before from a plant, without assignment of the double bond geometry in the p-coumaryl moiety.

The volatile composition of the fruits of three Annona species from Malaysia was investigated by capillary GC and GC-MS following isolation by simultaneous steam distillation-extraction. A total of fifty-one components were identified in the soursop volatiles, including eleven which have been previously reported in this fruit. Thirty-four volatile components were identified in the sweetsop and fifty-two in the bullock's heart. Most aroma components in the soursop were esters (57.2%), while terpenoid constituents predominated in the sweetsop and bullock's heart (88.5 % and 98.3 % respectively). KEY WORDS Annona muricata L. Soursop Annona sqwunosa L. Sweetsop Annona reticuhta L.Bullock's heart Annonaceae Fruit volatiles GC-MS Isolation of Volatile ComponentsThe pulp of each of the fully ripe fruits (6OOg), separated from skin and embedded d, was

The composition of the essential oil of rhizomes of Kuempferiu galanga L. growing in Malaysia has been investigated by capillary GC, GC-MS and 'H-NMR. The oil contained 54 components, of which the major constituents were ethyl trans-pmethoxycinnamate (51.6%), ethyl cinnamate (16.5 %). pentadecane (9.0%), 1,8-cineole (5.7 %), 6-car-3-ene (3.3%) and borneol (2.7 %). Terpenoid constituents amounted to 16.4%.

A number of Vitex species have been investigated as a source of potential bioactive compounds such as ecdysteroids [1], diterpenoids [2], iridoids [3], flavonoids, and phenolic compounds [4] demonstrating antioxidant, anti-inflammatory, antimicrobial, hepatoprotective, analgesic, antihistaminic, anti-implantation, and antiasthmatic activities [5,6]. Generally, ecdysteroids and iridoids have been explored as chemotaxonomic markers for the plants in the family Lamiaceae including Vitex species [7]. Vitex doniana Sweet (Lamiaceae) is a small to medium sized tree growing up to 25 m tall with no phytochemical report in spite of the available ethnopharmacological significance among different African communities [8], including use of water decoctions of different parts for treatment of stomach and rheumatic pains as well as inflammatory disorders [9,10]. Antidepressant effects and potentiation of sodium thiopental sleeping time, muscle relaxant [11], anti-inflammatory, and analgesic activities [8] of V. doniana leaf extracts have been reported as well as antihypertensive effects on normative and hypertensive rats, trypanocidal and antidiarrheal activities of the stem bark [12]. Recent indication of anti-inflammatory, anticonvulsant, and antipyretic properties of ethanol extracts [13] of V. doniana stem bark prompted a phytochemical analysis of the plantʼs stem bark for potential anti-inflammatory compounds. As a result of this study, isolation of three new phytoecdysteroids [21-hydroxyshidasterone (1), 11β-hydroxy-20-deoxyshidasterone (2), and 2,3-acetonide-24-hydroxyecdysone (3)] and four known phytoecdysteroids [shidasterone (4), ajugasterone C (5), 24-hydroxyecdysone (6), and 11β,24-dihydroxyecdysone (7)] with comparable anti-inflammatory activities as diclofenac are reported. Abstract !With reference to the ethnopharmacological significance of Vitex doniana Sweet (Lamiaceae) leaves in the treatment of stomach and rheumatic pains as well as inflammatory disorders, biological studies on its stem bark extracts have also reported anti-inflammatory and analgesic activities, with no attempt to identify the active components. Chromatographic and spectroscopic procedures identified three new phytoecdysteroids: 21-hydroxyshidasterone (1), 11β-hydroxy-20-deoxyshidasterone (2), and 2,3-acetonide-24-hydroxyecdysone (3) from the stem bark methanol extracts along with known ecdysteroids shidasterone (4), ajugasterone C (5), 24-hydroxyecdysone (6), and 11β,24-hydroxyecdysone (7). The compounds (1-7) showed significant (p ≤ 0.05) inhibitory effect at 100 mg/kg dose on rat paw oedema development due to carrageenan-induced inflammation in Sprague Dawley rats. These results suggest a possible contribution of ecdysteroids to the anti-inflammatory effect of some V. doniana stem bark extracts. Abbreviations

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