ABSTRACT
The medicinal plant, Syzygium leucoxylon or commonly known as Obah found in North Borneo was considered as traditional medicine by local committee. Two new phenolics, leucoxenols A (1) and B (2) were isolated and identified as major secondary metabolites from the leaves of S. leucoxylon. Their chemical structures were elucidated based on spectroscopic data such as NMR and HRESIMS. Furthermore, these compounds were active against selected strains of fungi.
Subject(s)
Phenols/chemistry , Plant Leaves/chemistry , Plants, Medicinal/chemistry , Syzygium/chemistry , Animals , Borneo , Brachyura/drug effects , Hyphae/drug effects , Lagenidium/drug effects , Larva/drug effects , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/pharmacologyABSTRACT
ãThe antifungal activity of two Bornean medicinal wild gingers Plagiostachys megacarpa and Zingiber phillippsiae were examined against Lagenidium thermophilum. The most active extract was P. megacarpa at concentration of 320 µg/mL inhibiting both hyphal growth and zoospore production of L. thermophilum in 24 h. Toxicity tests were conducted using mud crab (Scylla tranquebarica) larva. Bath treatment of P. megacarpa at concentrations of 320 and 640 µg/mL for 24 h were highly effective against hyphae and zoospores of the strain and it is non-toxic to mud crab larva. Therefore, crude extracts P. megacarpa may be used as alternative treatment for marine Oomycete infection of mud crab.
Subject(s)
Anti-Infective Agents/pharmacology , Asarum/chemistry , Brachyura/microbiology , Lagenidium/drug effects , Plant Extracts/pharmacology , Animals , Dose-Response Relationship, Drug , Infections/veterinaryABSTRACT
The essential oil composition of six species of wild Cinnamomum found in Borneo was investigated. The oils were obtained from bark by hydrodistillation and the volatile chemical profile was obtained via Gas Chromatography-Mass Spectrometry (GCMS). A total of 65 volatile constituents were identified, where the essential oils of the studied specimens contained high contents of oxygenated monoterpenes. Eucalyptol (1.2-31.1%), terpinen-4-ol (7.9-22.1%), eugenol (0.4-37.9%) and α-cadinol (0.4-1.8%) were detected consistently in the specimens studied. The oils of C. cuspidatum and C. crassinervium exhibited significant inhibition against Listeria monocytogenes, specifically the latter, which displayed a lower minimum bactericidal concentration (MBC) value against Staphylococcus aereus and L. monocytogenes. This result had highlighted the possible usage of the essential oil derived from wild cinnamom species against food borne pathogens.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cinnamomum/chemistry , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Bacteria/drug effects , Gas Chromatography-Mass SpectrometryABSTRACT
A new coumarin, 8,4''-dihydroxy-3'',4''-dihydrocapnolactone-2',3'-diol (1) and two known triterpenes, 5(6)-gluten-3-one (2) and 5(6)-gluten-3alpha-ol (3) were isolated from the leaves of Micromelum minutum (Rutaceae) collected from Sepilok, Sabah, Malaysia and their structures were characterized by spectroscopic methods.
Subject(s)
Coumarins/isolation & purification , Rutaceae/chemistry , Triterpenes/isolation & purification , Coumarins/chemistry , Magnetic Resonance Spectroscopy , Malaysia , Molecular Structure , Triterpenes/chemistryABSTRACT
A new flavonoid, dihydroglychalcone-A, was isolated from the leaves extract of Glycosmis chlorosperma in addition to two known sulphur-containing amides, dambullin and gerambullin. The structure of the new compound was assigned as 2'-hydroxy-4,6'-dimethoxy-3',4'-(2",2"-dimethylpyrano)dihydrochalcone. The extract of the leaves was also found to exhibit antimicrobial and cytotoxic activities.
Subject(s)
Flavonoids/chemistry , Rutaceae/chemistry , Chalcones , Flavonoids/isolation & purification , Flavonoids/pharmacology , Humans , Leukemia-Lymphoma, Adult T-Cell/pathology , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Leaves/chemistry , Tumor Cells, CulturedABSTRACT
In a continuation of our study of the Rutaceae, detailed chemical investigation on Micromelum minutum (Rutaceae) collected from Sepilok, Sabah, Malaysia gave four new coumarins. The structures of the coumarins have been fully characterised by spectroscopic methods as 3",4"-dihydrocapnolactone 1, 2',3'-epoxyisocapnolactone 2, 8-hydroxyisocapnolactone-2',3'-diol 3 and 8-hydroxy-3",4"-dihydrocapnolactone-2',3'-diol 4.
