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The effect of microwave irradiation on Z‐isomerization of (all‐E)‐lycopene contained in tomato oleoresin is investigated, and the Z‐isomerization efficiency is compared to that of the conventional oil‐bath heating method. With a 4‐min microwave treatment at 2450 MHz frequency and 500 W power, the total Z‐isomer content of lycopene increased to approximately 70%, almost without decomposition, and the efficiency, at the same temperature, is higher than that with conventional heating. In both treatments, the (9Z)‐ and (13Z)‐isomers are mainly formed. Moreover, the effect of addition of vegetable oils to the oleoresin on the Z‐isomerization by microwave irradiation is examined. When roasted seed oils and garlic oil are added, the production of (5Z)‐lycopene, an isomer having higher functionality and storage stability among the Z‐isomers, is significantly increased. This work reveals that the promoting effect is probably caused by the presence of disulfide compounds existing commonly in the above oils: Thiyl radicals, produced from disulfide compounds by microwave irradiation, would act as a catalyst for the Z‐isomerization reaction. Practical Applications: Z‐Isomers of lycopene, which are the predominant forms in the human body, have higher bioavailability and antioxidant capacity than the all‐E‐isomer, which is the major configuration form in raw tomatoes. Thus, appropriate methods are required to achieve the efficient Z‐isomerization of (all‐E)‐lycopene. This study has developed an efficient production method for lycopene Z‐isomers by microwave irradiation of (all‐E)‐lycopene in edible vegetable oils containing disulfide compounds, in which neither organic solvents nor food additives are used. It would be practically feasible to utilize this procedure not only for food, drink, and dietary supplement manufacturing, but also for daily cooking. (all‐E)‐Lycopene in tomato oleoresin is efficiently isomerized to the Z‐isomers by microwave irradiation and the Z‐isomerization is accelerated by adding vegetable oils containing disulfide compounds. [ABSTRACT FROM AUTHOR]

(15 Z )-Lycopene was prepared by thermal isomerization of (all- E )-lycopene derived from tomatoes, and isolated by using a series of chromatographies. The fine red crystalline powder of (15 Z )-lycopene was obtained from 556 mg of (all- E )-lycopene with a yield of 0.6 mg (purity: reversed-phase HPLC, 97.2%; normal-phase HPLC, ≥99.9%), and 1 H and 13 C NMR spectra of the isomer were fully assigned. More refined computational analyses that considered differences in the energy levels of the conformers involved in isomerization have also determined the stabilities of (15 Z )-lycopene and other geometric isomers, along with the activation energies during isomerization from the all- E form. The fine control of conditions for HPLC separation and an advanced theoretical insight into geometric isomerization have led to the discovery of the 15 Z -isomer generated from a natural source. [ABSTRACT FROM AUTHOR]

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The article focuses on a study related to the identification of novel esterase which shows activity for aryl-carboxylesterase (EstAC) in Sporosarcina species. As per the study, EstAC was characterized as a monomeric protein with molecular weight 43,000, pH 9.0 and temperature 40 °C. The study mentions that EstAC was purified from crude cell extracts. The study further concludes that EstAC have 4-hydroxybenzoyl and cinnamoyl esterase activities.

Two poly(ℇ-l-lysine) (ℇ-PL) producer strains of Streptomyces celluloflavus secreted a novel polymeric substance into their culture broths along with ℇ-PL. Three types of HPLC analysis plus one- and two-dimensional 1H and 13C nuclear magnetic resonance experiments revealed that the secreted substance was poly(γ-l-diaminobutanoic acid) (γ-PAB), anl-α,γ-diaminobutanoic acid (l-DAB) homopolymer linking between γ-amino and α-carboxylic acid functional groups. The γ-PABs from the two strains had an identical chemical structure, and the same number-average molecular weight of 2100–2200. No copolymers composed of the two amino acidsl-DAB andl-lysine were found in either of the broths from the producers. Both strains coproduced high levels of the two poly(amino acid)s in the presence of SO42− at pH 4.0 and 4.5 L min−1 aeration in a 5-L jar fermentor. γ-PAB exhibited strong inhibitory activities against various yeasts and weaker actions against bacteria than ℇ-PL. γ-PAB may have various biological functions similar to ℇ-PL, and the use of γ-PAB along with ℇ-PL would be advantageous for technical applications in various fields. [ABSTRACT FROM AUTHOR]

Background: SERCA maintains intracellular Ca 2+ homeostasis by sequestering cytosolic Ca 2+ into SR/ER stores. Two primary fatty acid amides (PFAAs), oleamide (18:1 9-cis ) and linoleamide (18:2 9,12-cis ), induce an increase in intracellular Ca 2+ levels, which might be caused by their inhibition of SERCA., Methods: Three major SERCA isoforms, rSERCA1a, hSERCA2b, and hSERCA3a, were individually overexpressed in COS-1 cells, and the inhibitory action of PFAAs on Ca 2+ -ATPase activity of SERCA was examined., Results: The Ca 2+ -ATPase activity of each SERCA was inhibited in a concentration-dependent manner strongly by linoleamide (IC 50 15-53μM) and partially by oleamide (IC 50 8.3-34μM). Inhibition by other PFAAs, such as stearamide (18:0) and elaidamide (18:1 9-trans ), was hardly or slightly observed. With increasing dose, linoleamide decreased the apparent affinity for Ca 2+ and the apparent maximum velocity of Ca 2+ -ATPase activity of all SERCAs tested. Oleamide also lowered these values for hSERCA3a. Meanwhile, oleamide uniquely reduced the apparent Ca 2+ affinity of rSERCA1a and hSERCA2b: the reduction was considerably attenuated above certain concentrations of oleamide. The dissociation constants for SERCA interaction varied from 6 to 45μM in linoleamide and from 1.6 to 55μM in oleamide depending on the isoform., Conclusions: Linoleamide and oleamide inhibit SERCA activity in the micromolar concentration range, and in a different manner. Both amides mainly suppress SERCA activity by lowering the Ca 2+ affinity of the enzyme., General Significance: Our findings imply a novel role of these PFAAs as modulators of intracellular Ca 2+ homeostasis via regulation of SERCA activity., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Unlabelled: Catalytic isomerization of (all-E)-lycopene to Z-isomers using iron(III) chloride was investigated and optimized under various conditions of solvents, concentrations of iron(III) chloride, and reaction temperatures. The total contents of Z-isomers converted were higher in the order of CH2 Cl2 (78.4%) > benzene (61.4%) > acetone (51.5%) > ethyl acetate (50.8%) at 20 °C for 3 h using 1.0 × 10(-3) mg/mL iron(III) chloride for 0.1 mg/mL (all-E)-lycopene. However, the decomposition of lycopene was markedly accelerated in CH2 Cl2 : the remaining lycopene after the reaction for 3 h and 12 h was only 79.4% and 47.5%, respectively. As the concentration of catalyst increased in acetone, the Z-isomerization ratio of lycopene increased to more than 80%, followed by rapid degradation of lycopene to undetectable levels using >4.0 × 10(-3) mg/mL iron(III) chloride with the above concentration of (all-E)-lycopene. Finally, greater isomerization (79.9%) was attained at 60 °C in acetone for 3 h in the presence of 1.0 × 10(-3) mg/mL iron(III) chloride, largely without decomposition of lycopene (remaining ratio of total amount of lycopene isomers after the reaction, 96.5%). As iron(III) chloride has found general use as a food additive for iron fortification and acetone is also widely used in the food field, this method can be applied to the food and beverage processing industry., Practical Application: The dietary intake of lycopene, a natural red pigment found in brightly colored vegetables and fruits such as tomatoes and watermelons, has been reported to lower the risk of some diseases, including cancer. Lycopene molecules occur naturally in a long and “straight” shape, but on the other hand lycopene molecules with “bent” forms are highly absorbed by living cells, and showed good antioxidant activity. This study has demonstrated the efficient production of the “bent” lycopene using ionic iron as an accelerator, which is often contained in nutritional supplements., (© 2015 Institute of Food Technologists®)

The asymmetric unit of the title compound, C18H16O4, contains two crystallographically independent mol-ecules. The anthra-quinone ring systems are slightly bent with dihedral angles of 2.33 (8) and 13.31 (9)° between the two terminal benzene rings. In the crystal, the two independent mol-ecules adopt slipped-parallel π-overlap with an average inter-planar distance of 3.45 Å, forming a dimer; the centroid-centroid distances of the π-π inter-actions are 3.6659 (15)-3.8987 (15) Å. The mol-ecules are also linked by C-H⋯O inter-actions, forming a tape structure along the a-axis direction. The crystal packing is characterized by a dimer-herringbone pattern.

In an attempt to brominate 1,4-diprop-oxy-9,10-anthra-quinone, a mixture of products, including the title compound, C14H7BrO4, was obtained. The mol-ecule is essentially planar (r.m.s. deviation = 0.029 Å) and two intra-molecular O-H⋯O hydrogen bonds occur. In the crystal, the mol-ecules are linked by weak C-H⋯O hydrogen bonds, Br⋯O contacts [3.240 (5) Å], and π-π stacking inter-actions [shortest centroid-centroid separation = 3.562 (4) Å], generating a three-dimensional network.

A large amount of (all-E)-lycopene was successfully purified from tomato paste using an improved method that included a procedure to wash crystalline powder with acetone. The total yield of the pure (all-E) form was at least 30%. The melting point of (all-E)-lycopene was determined to be 176.35 °C by differential scanning calorimetry (DSC) measurements. Bathochromic shifts were observed in the absorption maxima of all solvents tested (at most a 36 nm shift for λ2 in carbon disulfide, as was observed in hexane) and were accompanied by absorbance decreases, namely, a hypochromic effect, showing a higher correlation between the position and the intensity of the main absorption bands. This bathochromic shift was dependent upon the polarizability of the solvent rather than its polarity. The structure of (all-E)-lycopene in CDCl3 and C6D6 was identified on the basis of one- and two-dimensional nuclear magnetic resonance (NMR) spectra, including (1)H and (13)C NMR, homonuclear correlation spectroscopy ((1)H-(1)H COSY), heteronuclear multiple-quantum coherence (HMQC), and heteronuclear multiple-bond connectivity (HMBC). The rate constants of the decrease in (all-E)-lycopene with hexane and benzene were calculated to be 3.19 × 10(-5) and 3.55 × 10(-5) s(-1), respectively. The equilibrium constants between (all-E) and (13Z) isomers were estimated to be 0.29 in hexane and 0.31 in benzene, respectively, from the point at which the amount of (13Z)-lycopene reached its maximum.