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Green tomato (Physalis ixocarpa) is a specie native to Mexico, and it is known as "tomatillo" or "husk tomato". The fruit contains vitamins, minerals, phenolic compounds, and steroidal lactones, presenting antimicrobial activity and antinarcotic effects. Therefore, it is not only used in traditional Mexican cuisine, but also in traditional medicine to relieve some discomforts such as fever, cough, and amygdalitis. However, it is a perishable fruit whose shelf life is very short. As a part of the peel, cuticle, and epicuticular waxes represent the most important part in plant protection, and the specific composition and structural characterization are significant to know how this protective biopolymer keeps quality characteristics in fresh fruits. P. ixocarpa cutin was obtained by enzymatic treatments (cellulase, hemicellulose, and pectinase) and different concentrations of TFA, and studied through Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (CPMAS 13C NMR), Ultra-High Performance Liquid Chromatography coupled to Mass Spectrometry (UHPLC-MS), and was morphologically characterized by Confocal Laser Scanning Microscopy (CLSM) and Scanning Electron Microscopy (SEM). The main constituents identified under the basis of UHPLC-MS analysis were 9,10,18-trihydroxy-octadecanoic acid and 9,10-epoxy-18-hydroxy-octadecanoic acid with 44.7 and 37.5%, respectively. The C16 absence and low occurrence of phenolic compounds, besides the presence of glandular trichomes, which do not allow a continuous layer on the surface of the fruit, could be related to a lower shelf life compared with other common fruits such as tomato (Solanum lycopersicum). [ABSTRACT FROM AUTHOR]

Gymnosperma glutinosum is a plant popularly known as "popote", "tatalencho", "tezozotla" or "pegajosa", and it is used in traditional medicine in the region of Tehuacán, Puebla (Mexico), for the treatment of jiotes and acne and to cure diarrhea using the aerial parts in infusions. To analyze the phytochemical composition, we have developed a rapid protocol for the extraction and separation of the components of the aerial parts of G. glutinosum. After a maceration process, chloroformic and methanolic extracts were obtained and analyzed. Extracts were evaluated by GC-MS (gas chromatography-mass spectrometry), and their composition revealed the presence of (−)-α-bisabolol (BIS) as the main component in the chloroformic extract, which was isolated and analyzed by 1H NMR to confirm its presence in the plant. The analysis of methanolic extracts by UPLC-MS (ultra-performance liquid chromatography-mass spectrometry) revealed the occurrence of six methoxylated flavones with m/z 405.08 (C19H18O10), m/z 419.09 (C20H20O10) and m/z 433.11 (C21H22O10), and a group of C20-, C18-hydroxy-fatty acids, which give the plant its sticky characteristic. The presence of BIS, an important sesquiterpene with therapeutic skin effects, as well as some antioxidant compounds such as methoxylated flavones and their oils, could play an important role in cosmetology and dermatology formulations. [ABSTRACT FROM AUTHOR]

Background: Although the plant Rauvolfia tetraphylla is used for the treatment of cancer in the traditional medicine of some regions of Mexico, its cytotoxic activity has not been subjected to rigorous investigation. Objective: The aim of the present study was to carry out a bioassay-guided fractionation of Rauvolfia tetraphylla leaves to evaluate the activity on cervical cancer (HeLa) and normal cells. Materials and Methods: Of hexane, dichloromethane and methanol extracts, hexane extract showed the most cytotoxic activity. Its most active fraction was characterized by mass spectrometry and assessed for cytotoxicity (by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays and trypan blue staining) on cervical cancer (HeLa) cells, normal human (HaCat) cells, and other cancer cell lines: A549, Caco-2, MDA-MB-231, and MCF7. Cisplatin served as the reference drug. Apoptosis was explored as a possible mechanism of action by examining DNA fragmentation and phosphatidylserine translocation. Results: The active fraction, composed of at least 5 constituents, was cytotoxic to all cancer cell lines, especially HeLa cells (IC30= 20.10 ± 1.1 μg/mL). To a lesser extent, it was also cytotoxic to normal cells (HaCat; IC30= 40.04 ± 12.78 μg/mL), indicating certain selectivity. Its mechanism of action in HeLa cells involved apoptosis. Conclusion: The active fraction of the hexane extract of R. tetraphylla was cytotoxic to cancer cells and did not produce excessive damage to normal cells. Apoptosis was apparently part of the mechanism of cytotoxicity. [ABSTRACT FROM AUTHOR]

Quinoxalines display diverse and interesting pharmacological activities as antibacterial, antiviral, antiparasitic and anticancer agents. Particularly, their 1,4-di-N-oxide derivatives have proved to be cytotoxic agents that are active under hypoxic conditions as that of solid tumours. A new series of quinoxaline 1ˏ4-di-N-oxide substitutes at 7-position with esters group were synthetized and characterized by infrared (IR), proton nuclear magnetic resonance (¹H-NMR), spectroscopy, and elemental analysis. Seventeen derivatives (M1-M3, E1-E8, P1-P3 and DR1-DR3) were selected and evaluated for antitumor activities using the NCI-60 human tumor cell lines screen. Results showed that E7, P3 and E6 were the most active compounds against the cell lines tested. Substitutions at 7-position with esters group not necessarily affect the biological activity, but the nature of the esters group could exert an influence on the selectivity. Additionally, substitutions at 2-position influenced the cytotoxic activity of the compounds. [ABSTRACT FROM AUTHOR]

Complete and unambiguous 1H NMR chemical shift assignment of α-cedrene ( 2) and cedrol ( 9), as well as for α-pipitzol ( 1), isocedrol ( 10), and the six related compounds 3-8 has been established by iterative full spin analysis using the PERCH NMR software (PERCH Solutions Ltd., Kuopio, Finland). The total sets of coupling constants are described and correlated with the conformational equilibria of the five-membered ring of 1-10, which were calculated using the complete basis set method. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: An anionic potato peroxidase (EC 1.11.1.7, APP) thought to be involved in suberization after wounding was isolated from slices of Solanum tuberosum in order to elucidate the first steps of dehydrogenative polymerization between pairs of different hydroxycinnamic acids (FA, CafA, CA and SA) present in wound-healing plant tissues. Use of a commercial horseradish peroxidase (HRP) – H2O2 catalytic system gave the identical major products in these coupling reactions, providing sufficient quantities for purification and structural elucidation. Using an equimolar mixture of pairs of hydroxycinnamic acid suberin precursors, only caffeic acid is coupled to ferulic acid and sinapic acid in separate cross-coupling reactions. For the other systems, HRP and APP reacted as follows: (1) preferentially with ferulic acid in a reaction mixture that contained p-coumaric and ferulic acids; (2) with sinapic acid in a mixture of p-coumaric and sinapic acids; (3) with sinapic acid in a mixture of ferulic and sinapic acids; (4) with caffeic acid in a reaction mixture of p-coumaric and caffeic acids. The resulting products, isolated and identified by NMR and MS analysis, had predominantly β-β-γ-lactone and β-5 benzofuran molecular frameworks. Five cross-coupling products are described for the first time, whereas the β-O-4 dehydrodimers identified from the caffeic acid and sinapic acid cross-coupling reaction are known materials that are highly abundant in plants. These reactivity trends lead to testable hypotheses regarding the molecular architecture of intractable suberin protective plant materials, complementing prior analysis of monomeric constituents by GC–MS and polymer functional group identification from solid-state NMR, respectively. [Copyright &y& Elsevier]

10,16-dihydroxyhexadecanoic acid obtained from agroresidual tomato waste, was oxidized to produce 7-oxohexadecanedioic acid in good yield (>70%) and purified without oxidation side products in one step. Polycondensation with 1,8-octanediol, yielded the polyester (poly(ω-carboxyl PA-co-OD)) with Mw = 2155.15 and Mn = 1637.27. The best enzymatic reaction conditions to get the polyester were using lipase CAL-B (%-by-wt relative to monomer) in toluene as a solvent for 1 h at 60 °C. The poly(ω-carboxyl PA-co-OD) was characterized by 1H- and 13C-NMR, mass spectrometry (MALDI-TOF) and the polyester film formed with a Langmuir-Blodgett Trough was analyzed by means of spectroscopic ellipsometry and atomic force microscopy. [ABSTRACT FROM AUTHOR]

Complete and unambiguous 1 H NMR chemical shift assignment of α-cedrene (2) and cedrol (9), as well as for α-pipitzol (1), isocedrol (10), and the six related compounds 3-8 has been established by iterative full spin analysis using the PERCH NMR software (PERCH Solutions Ltd., Kuopio, Finland). The total sets of coupling constants are described and correlated with the conformational equilibria of the five-membered ring of 1-10, which were calculated using the complete basis set method. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)

A peroxidase (EC 1.11.1.7) has been isolated and purified from Senna angustifolia. The enzyme was purified by ion-exchange chromatography on high Q and high S columns. SDS-PAGE electrophoresis showed that the protein has a molecular mass of approximately 70 kDa. Hydroxy-anthraquinones and hydroxy-anthracenones were evaluated as substrate of S. angustifolia and horseradish peroxidases. Both peroxidases catalyzed the oxidation of alizarin and purpurin anthraquinones to the corresponding 3,3'-bializarin and the new compound 3,3'-bipurpurin, respectively, as well as the formation of 2,2'-biquinizarin from quinizarin anthracenone. The K(Mapp) and V(max) values for alizarin and purpurin were 97 and 95 microM, and 1.5 and 2.1 microM min(-1) mg prot(-1), respectively. The results suggest that peroxidase may participate in the biogenesis of anthraquinones.