Duang Buddhasukh

Antifungal activity of turmeric oil extracted from Curcuma longa (Zingiberaceae).

Turmeric oil and curcumin, isolated from Curcuma longa L., were studied against fifteen isolates of dermatophytes, four isolates of pathogenic molds and six isolates of yeasts. The inhibitory activity of turmeric oil was tested in Trichophyton-induced dermatophytosis in guinea pigs. The results showed that all 15 isolates of dermatophytes could be inhibited by turmeric oil at dilutions of 1:40-1:320. None of the isolates of dermatophytes were inhibited by curcumin. The other four isolates of pathogenic fungi were inhibited by turmeric oil at dilutions of 1:40-1:80 but none were inhibited by curcumin. All six isolates of yeasts tested proved to be insensitive to both turmeric oil and curcumin. In the experimental animals, turmeric oil (dilution 1:80) was applied by dermal application on the 7th day following dermatophytosis induction with Trichophyton rubrum. An improvement in lesions was observed in 2-5 days and the lesions disappeared 6-7 days after the application of turmeric oil.

Modulation of human multidrug-resistance MDR-1 gene by natural curcuminoids.

BackgroundMultidrug resistance (MDR) is a phenomenon that is often associated with decreased intracellular drug accumulation in patients tumor cells resulting from enhanced drug efflux. It is related to the overexpression of a membrane protein, P-glycoprotein (Pgp-170), thereby reducing drug cytotoxicity. A variety of studies have tried to find MDR modulators which increase drug accumulation in cancer cells.MethodsIn this study, natural curcuminoids, pure curcumin, demethoxycurcumin and bisdemethoxycurcumin, isolated from turmeric (Curcuma longa Linn), were compared for their potential ability to modulate the human MDR-1 gene expression in multidrug resistant human cervical carcinoma cell line, KB-V1 by Western blot analysis and RT-PCR.ResultsWestern blot analysis and RT-PCR showed that all the three curcuminoids inhibited MDR-1 gene expression, and bisdemethoxycurcumin produced maximum effect. In additional studies we found that commercial grade curcuminoid (approximately 77% curcumin, 17% demethoxycurcumin and 3% bisdemthoxycurcumin) decreased MDR-1 gene expression in a dose dependent manner and had about the same potent inhibitory effect on MDR-1 gene expression as our natural curcuminoid mixtures.ConclusionThese results indicate that bisdemethoxycurcumin is the most active of the curcuminoids present in turmeric for modulation of MDR-1 gene. Treatment of drug resistant KB-V1 cells with curcumin increased their sensitivity to vinblastine, which was consistent with a decreased MDR-1 gene product, a P-glycoprotein, on the cell plasma membrane. Although many drugs that prevent the P-glycoprotein function have been reported, this report describes the inhibition of MDR-1 expression by a phytochemical. The modulation of MDR-1 expression may be an attractive target for new chemosensitizing agents.

Microwave-Assisted Isolation of Essential oil of Cinnamomum iners Reinw. ex Bl.: Comparison with Conventional Hydrodistillation

Microwave-assisted hydrodistillation was used to isolate an essential oil from the leaves of Cinnamomum iners Reinw. ex Bl., and the results compared with those obtained by conventional hydrodistillation. The composition of the oil from both methods was found to be similar, and (-)-linalool was found as the main component (30-50%). The antioxidant activity of the essential oil obtained by both methods was evaluated using DPPH, ABTS, FRAP and lipid peroxidation methods, all of which indicated the same but insignificant activity.

HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC SEPARATION AND QUANTITATION OF STEVIOSIDE AND ITS METABOLITES

A method of analysis using high performance liquid chromatography (HPLC) was developed for the separation and quantitation of the metabolites of stevioside: steviol-16,17α-epoxide, 15α-hydroxysteviol, steviolbioside, isosteviol, and steviol. The separation was carried out on a reversed-phase C18 Nova-Pack column with gradient elution of acetonitrile/water mixture. The applicability of the method was demonstrated in the detection and separation of stevioside and its metabolites found in blood, feces, and urine of hamsters after ingestion of stevioside.

Synthesis of (+/-)epipentenomycin I and III

Abstract A synthesis of (±) epipentenomycin I and III is reported from a regioselective epoxidation of racemic 3-hydroxy- and 3-acetoxy-2-methylene-4-cyclopentenone, respectively, with dimethyldioxirane followed by hydrolytic ring-opening of the resulting epoxide.

Electrocoagulation of Quinone Pigments

Some representative quinones, viz. one naphthoquinone (plumbagin) and five anthraquinones (alizarin, purpurin, chrysazin, emodin, and anthrarufin), were subjected to electrocoagulation. It was found that the rate and extent of coagulation of these compounds appears to correlate with the number and relative position of their phenolic substituent groups, and that all of the coagulated quinones could be recovered. Attempts were then made to electrochemically isolate three quinones, namely plumbagin, morindone and erythrolaccin, from natural sources.

Microwave-assisted facile synthesis and crystal structure of cis-9,10,11,15-tetrahydro-9,10[3'4']-furanoanthracene-12,14-dione

Abstract A facile synthesis and crystal structure of cis‐9,10,11,15‐tetrahydro‐9,10[3′,4′]‐furanoanthracene‐12,14‐dione from the reaction of anthracene and maleic anhydride in xylene in a short time and high yield using a modified commercial domestic microwave oven is reported.

Facile microwave-assisted synthesis of 9,10-dihydro-9,10-ethanoanthracene-11-carboxylic acid methyl ester.

A facile, high yielding synthesis of 9,10-dihydro-9,10-ethano- anthracene-11-carboxylic acid methyl ester using a modified commercial domestic microwave oven is reported.

Dechlorophyllation by Electrocoagulation

Electrocoagulation was used for dechlorophyllation of alcoholic extracts from five plants. The results showed that for every plant extract studied, electrocoagulation was more efficient than the classical solvent extraction method in removing plant pigments, while not affecting the important secondary metabolites in those extracts.

Solvent Effects in Electrocoagulation of Selected Plant Pigments and Tannin

Electrocoagulation of a plant extract and certain substances representative of selected classes of plant pigments, viz. chlorophyll, a carotenoid, a phenolic substance and a tannin, was performed in ethanol containing varying amounts of water (15-75%). The results showed that the extent and efficiency of coagulation of these substances tends to vary in a manner directly related to the water content of the solvent, although the tannin and the phenolic substance were less sensitive to the solvent composition and are equally well coagulated in all solvent systems studied. The findings can be applied to the removal of these substances from aqueous alcoholic plant extracts using the electrocoagulation technique.