Two new alkaloids from Crinum asiaticum var. japonicum.

A new crinine-type alkaloid crijaponine A (1), a new galanthamine-type alkaloid crijaponine B (2), and 11 known alkaloids-ungeremine (3), lycorine (4), 2-O-acetyllycorine (5), 1, 2-O-diacetyllycorine (6), (-)-crinine (7), 11-hydroxyvittatine (8), hamayne (9), (+)-epibuphanisine (10), crinamine (11), yemenine A (12), and epinorgalanthamine (13)-were isolated from the rhizome and fruits of Crinum asiaticum var. japonicum. The structural elucidation of the isolated compounds was performed by spectroscopic methods including 2D NMR. The isolated compounds were evaluated for cytotoxicity against HeLa and HL-60 cells lines and were tested for acetylcholinesterase inhibition activity.

Two new coumarins and a new xanthone from the leaves of Rhizophora mucronata.

Two new coumarins (1, 2) and a new xanthone (3), together with 14 known compounds-eight coumarins (4, 5, 9, 10, 12-15), three xanthones (11, 16, 17), a benzoic acid (6) and two flavonones (7, 8)-were isolated from the leaves of Rhizophora mucronata. The structures of the compounds were elucidated by spectroscopic (IR, MS, and NMR) analyses. The isolated compounds were tested for cytotoxicity against human cancer cell lines HL-60 and HeLa. Among these compounds, only compound 16 inhibited the growth of both HeLa (IC50 = 4.8 µM) and HL-60 (IC50 = 1.0 µM) cells. Compounds 4, 7, 10, and 12 exhibited moderate activity against HeLa cells (IC50 = 3.8-8.3 µM). Compounds 5, 9, 11, and 17 showed moderate activity against HL-60 cells (IC50 = 2.2-6.3 µM). Higher selectivity against HL-60 cell lines was observed for compounds 5, 9, 11, and 16 with SI values (NIH 3T3/HL-60) of 8.6, 19.2, 9.4, and 10.2, respectively.

Kinetic characterization of small DNA-binding molecules interacting with a DNA strand on a quartz crystal microbalance.

Quantitative studies of the binding of various DNA-binding antibiotics with dsDNA are useful for drug design, not only for effective antibiotics, but also for antitumor drugs. We studied the binding kinetics, association and dissociation rate constants, and association constants (kon, koff, and Ka, respectively) of intercalators and groove binders, including various antibiotics, to double-stranded DNA (dA30·dT30 and dG30·dC30) immobilized on a highly sensitive 27 MHz quartz-crystal microbalance (QCM) in aqueous solution. Although a simple ethidium bromide intercalator bound to both dA30·dT30 and dG30·dC30, antibiotics that are side-binding intercalators, such as daunomycin, aclacinomycin A, and actinomycin D, with sugar or peptide moieties on the intercalator parts selectively bound to dG30·dC30 with high Ka and small koff values. Nogalamycin, a dumbbell-shaped penetrating intercalator, showed low kon and koff values owing to slow duplex unwinding during the penetration process. Groove binders (Hoechst 33258, distamycin A, and mithramycin) had high Ka values owing to the high kon values. Kinetic parameters depended largely on molecular shapes and DNA-binding molecule binding modes.

Tocopherol profile of Brazil nut oil from different geographic areas of the Amazon region / Perfil de tocoferol de castanha-do-Brasil de diferentes áreas geográficas da região Amazônica

The tocopherol content of Brazil nut oil from different Amazon regions (Manicoré-AM, Rio Preto da Eva-AM, São João da Baliza-RR, Caroebe-RR, Belém-PA, and Xapurí-AC) was investigated by normal-phase high-performance liquid chromatography. For all authentic oils, two isomers: α- and γ-tocopherols were observed (37.92-74.48 µg g-1, 106.88-171.80 µg g-1, respectively), and their levels were relatively constant among the oils having these geographic origins, which would enable to distinguish Brazil nut oil from other plant oils for authentication purposes. Commercial Brazil nut oils were also evaluated, and some of these oils demonstrated a tocopherol content that was very different from that of the authentic oils. Therefore, we suggest that the tocopherol profile of Brazil nut oil can be useful chemical marker for quality control and authentication.

O teor de tocoferol de óleo de castanha-do-Brasil proveniente de diferentes regiões da Amazônia (Manicoré-AM, Rio Preto da Eva-AM, São João da Baliza-RR, Caroebe-RR, Belém-PA e Xapurí-AC) foi investigado através de cromatografia líquida de alta eficiência em fase normal. Em todos os óleos autênticos, dois isômeros, α- e γ-tocoferóis (37,92-74,48 µg g-1, 106,88-171,80 µg g-1, respectivamente), foram observados, e seus níveis foram relativamente constantes em todos os óleos destas origens geográficas, o que pode distinguir o óleo de castanha-do-Brasil dos óleos de outras plantas, em termos de autenticidade. Os óleos comerciais de castanha-do-Brasil também foram avaliados e alguns mostraram teor de tocoferol muito diferente que o dos óleos autênticos. Portanto, sugere-se que o perfil de tocoferol do óleo de castanha-do-Brasil pode ser usado como marcador químico para controle de qualidade e autenticação.

Brazil nut oil: quality control via triacylglycerol profiles provided by easy ambient sonic-spray ionization mass spectrometry.

Brazil nut oil is one of the important Amazonian natural products in the global market. Despite its health benefits and applications in food and cosmetic industries, authentication and quality control of the oil are far from satisfactory. Several samples of Amazonian Brazil nut oil (authentic oils of different geographic origins, commercial oils, and oils adulterated with soybean oil) were evaluated by easy ambient sonic-spray ionization mass spectrometry (EASI-MS). The samples were characterized on the basis of triacylglycerol profiles, and their major ions were subjected to chemometric treatment (principal component analysis). The ambient mass spectrometry analysis and the set of major ions allowed the characterization of authentic oils, commercial oils, and adulterated oils (5% soybean oil) in a few minutes and without sample preparation. Therefore, it is shown that quality control of Amazonian vegetable oils can be readily accomplished by EASI-MS.