Bioactive styryllactones and alkaloid from flowers of Goniothalamus laoticus.
BACKGROUND
Goniothalamus laoticus (Annonaceae) is being used traditionally as a tonic and a febrifuge by the local people in the northeastern part of Thailand.


OBJECTIVE
To investigate the Thai medicinal plant, Goniothalamus laoticus, for antiplasmodial, antimycobacterial and cytotoxicity activities.


METHODS
The flowers extracts of Goniothalamus laoticus were isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods. The antiplasmodial, antimycobacterial and cytotoxicity evaluation of styryllactone derivatives and alkaloid were also performed.


RESULTS
Ten compounds, cinnamic acid (1); dihydrochrysine (2); beta-sitosterol (3); six styryllactones, (+)-3-acetylaltholactone (4), goniotriol (5), (+)-altholactone (6), (+)-goniofufurone (7), 9-deoxygoniopypyrone (8), howiinin A (9); and an aporphine alkaloid; (-)-nordicentrine (10) were isolated from flowers of Goniothalamus laoticus. Among these, compounds 1, 3-5, 8-10 are first isolated from the Goniothalamus laoticus. Besides, compound 10 is the first report from the Goniothalamus genus. The isolated compounds were evaluated in antiplasmodial, antimycobacterial and anticancer cell lines tests. Compounds 4-6 and 10 exhibited antiplasmodial activity against Plasmodium falciparum (IC(50) 2.6, 7.9, 2.6 and 0.3 microg/mL, respectively), while 5, 6, 9 and 10 showed antimycobacterial activity against Mycobacterium tuberculosis (MIC 100, 6.25, 6.25 and 12.5 microg/mL, respectively). In addition, compounds 4-10 showed cytotoxicity against cancer cells, KB, BC1, NCI-H187, and MCF-7 with IC(50) ranging from 0.4 to 22.7 microg/mL.


CONCLUSIONS
This finding showed that the styryllactone derivatives and alkaloid isolated from the flowers of Goniothalamus laoticus exhibited antiplasmodial activity against Plasmodium falciparum, antimycobacterail against Mycobacterium tuberculosis and cytotoxicity against four cancer cell lines.
Lekphrom
Ratsami
R
Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
Kanokmedhakul
Somdej
S
Kanokmedhakul
Kwanjai
K
D000470:Alkaloids / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D035264:Flowers; D054335:Goniothalamus / Q000737:chemistry*; D006801:Humans; D007783:Lactones / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D010963:Plasmodium falciparum / Q000187:drug effects
D000470:Alkaloids; D007783:Lactones; D010936:Plant Extracts