ABSTRACT
The stability of andrographolide in powdered Andrographis Herb--the aerial part of Andrographis paniculata (Burm. f.) Nees (Acanthaceae)--was determined using a heat-accelerated experiment to reveal a second-order kinetics of degradation. The fast decomposition was observed regardless of the method of analysis. The rate constant of the decomposition of andrographolide at 25 degrees C ( K(25)( degrees C)), predicted from the Arrhenius plot, was 6.58 x 10 (-6) d (-1).
Subject(s)
Andrographis/chemistry , Diterpenes/chemistry , Hot Temperature , Diterpenes/isolation & purification , Drug Stability , Drug Storage/standards , KineticsABSTRACT
For the purpose of discovering anti-HIV-1 agents from natural sources, water and EtOH extracts of 50 Thai plants were screened for their inhibitory activity against HIV-1 integrase (IN), an enzyme essential for viral replication. Of these plants, an EtOH extract of Coleus parvifolius Benth. (aerial parts) showed potent activity against HIV-1 IN with an IC50 value of 9.2 microg/mL. From this extract, 11 compounds were isolated and identified as luteolin 5-O-beta-d-glucopyranoside (1), luteolin (2), luteolin 7-methyl ether (3), luteolin 5-O-beta-d-glucuronide (4), 5-O-beta-d-glucopyranosyl-luteolin 7-methyl ether (5), rosmarinic acid (6), rosmarinic acid methyl ester (7), daucosterol (8), a mixture of alpha- and beta-amyrin (9, 10) and phytol (11). Of these compounds, rosmarinic acid methyl ester (7), rosmarinic acid (6), luteolin (2) and luteolin 7-methyl ether (3) exhibited inhibitory activities against HIV-1 IN with IC50 values of 3.1, 5.0, 11.0 and 11.0 microM, respectively. Among rosmarinic acid derivatives, the HIV-1 IN inhibitory activity increased in turn for a dimer (IC50 = 5.0 microM), a trimer (IC50 = 1.4 microM), and a tetramer (IC50 = 1.0 microM).
Subject(s)
Anti-HIV Agents/pharmacology , Coleus , HIV Integrase/drug effects , HIV-1/drug effects , Phytotherapy , Plant Extracts/pharmacology , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/therapeutic use , Flowers , Fruit , Humans , Medicine, Traditional , Microbial Sensitivity Tests , Plant Extracts/administration & dosage , Plant Extracts/chemistry , Plant Extracts/therapeutic use , Plant Leaves , Plant Roots , Seeds , Thailand , Tumor Cells, Cultured/drug effectsABSTRACT
Two new flavanone glucosides, (2R)- and (2S)-5-O-beta-D-glucopyranosyl-7,4'-dihydroxy-3',5'-dimethoxyflavanone[pervianoside I (3), peruvianoside II(4)] and a new flavonol glycoside, quercetin 3-O-[beta-D-glucopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]-beta-D-galactopyranoside] (peruvianoside III, 13) were isolated from the leaves of Thevetia peruviana Schum., together with nine known flavonol glycosides and two known iridoid glucosides. The structures of all compounds were determined on the basis of chemical and spectroscopic methods. Their inhibitory effects against HIV-1 reverse transcriptase and HIV-1 integrase were also investigated.
