The Isolation of Lutein and Lutein 3'-methyl ether from Peristrophe lanceolaria.

Two carotenoids, lutein (1) and lutein 3'-methyl ether (2), have been isolated from the EtOAc fraction othe MeOH extract of Peristrophe lanceolaria, growing in Thailand. The structures of these compounds were elucidated from their ID and 2D NMR spectroscopic data and from comparisons made with the literature data. This is the first report of the isolation of lutein-3'-methyl ether as a natural product.

A new 1,6-benzoxazocine-5-one alkaloid isolated from the aerial parts of Peristrophe lanceolaria.

A new 1,6-benzoxazocine-5-one alkaloid has been isolated as its butyl acetal derivative (1) along with peristrophine from the n-BuOH and EtOAc fractions of the crude MeOH extract of the aerial parts of Peristrophe lanceolaria growing in Thailand. The structures of these compounds were elucidated on the basis of their spectroscopic data. These compounds were isolated for the first time from P. lanceolaria. The EtOAc and n-BuOH fractions also possessed significant antioxidant activity with IC50 values of 57 and 50 µg/mL, respectively (DPPH method), whereas 1 had an IC50 value of 23 µg/mL.

Chemical constituents and antioxidant and biological activities of the essential oil from leaves of Solanum spirale.

The essential oil of the leaves Solanium spirale Roxb. was isolated by hydrodistillation and analyzed for the first time using GC and GC-MS. Thirty-nine constituents were identified, constituting 73.36% of the total chromatographical oil components. (E)-Phytol (48.10%), n-hexadecanoic acid (7.34%), beta-selinene (3.67%), alpha-selinene (2.74%), octadecanoic acid (2.12%) and hexahydrofarnesyl acetone (2.00%) were the major components of this oil. The antioxidant activity of the essential oil was evaluated by using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. The oil exhibited week antioxidant activity with an IC50 of 41.89 mg/mL. The essential oil showed significant antibacterial activity against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus with MIC values of 43.0 microg/mL and 21.5 microg/mL, respectively. It also showed significant cytotoxicity against KB (oral cancer), MCF-7 (breast cancer) and NCI-H187 (small cell lung cancer) with the IC50 values of 26.42, 19.69, and 24.02 microg/mL, respectively.

The isolation of bioactive flavonoids from Jacaranda obtusifolia H. B. K. ssp. rhombifolia (G. F. W. Meijer) Gentry.

The paper describes the bioassay-guided isolation, structure elucidation and anticancer evaluation of five flavonoids (-)-liquiritigenin (1), (-)-neoliquiritin (2), isoliquiritigenin (3), isoliquiritin (4) and formononetin (5) from the twigs of Jacaranda obtusifolia H. B. K. ssp. rhombifolia (G. F. W. Meijer) Gentry. The structures were elucidated based on ¹H, ¹³C NMR, comprehensive 2D NMR, MS analyses and comparison with previously reported spectral data. Compounds 1 and 3 were demonstrated to be inhibitory in vitro against NCI-H187 (small cell lung cancer) with IC50 values of 30.1 and 16.6 µg mL⁻¹, respectively. The isolates were non-cytotoxic to Vero cells (African green monkey kidney).

Sequential injection analysis with lab-at-valve (SI-LAV) for the determination of solasodine in Solanum species.

The development of sequential injection analysis with lab-at-valve (LAV) semi-automated system on-line liquid-liquid extraction is demonstrated for spectrophotometric determination of solasodine in various Solanum species fruits. The main proposed is semi-automated extractive determination of solasodine using methyl orange as colorimetric reagent. After optimization of the system, sample, reagent and organic solvent were sequentially aspirated into an extraction coil connected to the center of a selection valve, where extraction took place by flow reversal. The aqueous and organic phases were separated in a lab-at-valve unit attracted to one of the ports of the selection valve. The absorption of ion-pair solasodine-methyl orange complex in the organic phase was measured spectrophotometrically at 420 nm. The method performances, including reproducibility, linearity, sensitivity and accuracy, were also evaluated. The proposed method is simple, reproducible and accurate. It was successfully applied to the determination of solasodine in Solanum aculeatissimum Jacq., Solanum violaceum Ortega., Solanum melongena Linn. and Solanum indicum Linn. fruits in Solanaceae family. Results obtained were in good agreement with those obtained by batch wise spectrophotometric method. It is also suitable and useful for determination of solasodine in other medicinal plants.

High-performance liquid chromatographic determination of arbutin in skin-whitening creams and medicinal plant extracts.

A high-performance liquid chromatographic method was developed for quantitative analysis of arbutin. The arbutin was separated on an ODS Hypersil C(18) column with a mobile phase of water:methanol:0.1 M hydrochloric acid (89:10:1, v/v/v). The level of arbutin was measured by means of UV detection at 222 nm. The optimum conditions for arbutin quantitative analysis were investigated. The calibration curve was found to be linear up to 1,000 microg/ml(-1) of arbutin concentration, and the working calibration curve for arbutin determination over the range 0.5-30.0 microg/ml(-1) of arbutin (r(2)=0.9999) was established. The relative standard deviations for intraday and interday were found to be 0.98% and 1.15%, respectively. A detection limit (3sigma) and quantitation limit (10sigma) of 0.02 microg/ml(-1) and 0.2 microg/ml(-1), respectively, and a mean percentage recovery of the spiked arbutin of 99.88 +/- 1.12% were obtained. The proposed method has been applied to the determination of arbutin in commercial skin-whitening creams (Arbuwhite cream, Super Whitening cream, and Shiseido cream) with average contents of 7.60, 5.30, and 57.90 mg/g(-1), respectively. It was also applied to the determination of arbutin in medicinal plant extracts from Betula alnoides Buch. Ham., Clerodendrum petasites S. Moore, Curculigo latifolia Dryand. Var. latifolia, and Hesperethusa crenulata (Roxb.) Roem, levels of which were found to be 3.50, 1.50, 1.10, and 0.12 microg/g(-1), respectively (no article reported in the literature about arbutin analysis). The proposed HPLC method is rapid, simple, and selective for routine analysis.

Gluco-indole alkaloids from Nauclea cadamba in Thailand and transformation of 3 alpha-dihydrocadambine into the indolopyridine alkaloid, 16-carbomethoxynaufoline.

Three monoterpenoid gluco-indole alkaloids, 3beta-isodihydrocadambine, cadambine, and 3alpha-dihydrocadambine, were isolated from Nauclea cadamba ROXB. growing in Thailand. The stereochemistry at C19 in 3beta-isodihydrocadambine was elucidated to be R by spectroscopic analysis. Treatment of 3alpha-dihydrocadambine with beta-glucosidase in aqueous ammonium acetate solution gave an indolopyridine alkaloid, 16-carbomethoxynaufoline, and an unusually rearranged compound.