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The influence of pumpkin seed roasting conditions (110-140 °C) and screw-pressing on the formation of previously undescribed Δ 7 -phytosterol oxidation products and tocopherylquinone adducts with nucleophilic phosphatidylethanolamine species was investigated. The roasting process of pumpkin seed paste at a temperature above 120 °C for 30 min considerably enhanced the formation of Δ 7 -oxysterols. Targeted analysis [electron impact mass spectrometry (MS), 1D-nuclear magnetic resonance] led to the identification of five novel markers of pumpkin paste roasting, among which (3β,5α,22 E ,24 S )-stigmasta-7,22-dien-6-one-3-ol (6-oxo-α-spinasterol), stereoisomers of (3β,5α,22 E )-7,8-epoxystigmast-22-en-3-ol (7,8-epoxy-α-spinasterol), and (3β,5α)-22,23-epoxystigmast-7-en-3-ol (7,8-epoxy-α-spinasterol) were reported in edible oils for the first time. Simulated culinary processing provided novel stereoisomers of (3β,5α,22 E )-stigmasta-7,22-dien-3,6-diol, unusual (3β,5α,22 E )-stigmasta-7,22-dien-6,15-dione-3-ol, and (5α,22 E )-stigmasta-7,22-dien-3-one accompanied by minor stereoisomers of (3β,5α)-7,8;22,23-diepoxystigmastan-3-ol. Moreover, a clear relationship between the pumpkin seed oil stability index and synergistic effect of glycerophospholipids with present tocochromanols was found. High-resolution atmospheric pressure chemical ionization-MS experiments clearly demonstrated the formation of various γ-tocopherylquinone adducts with primary amines, namely, octylamine. The mitigation strategy of potentially detrimental oxysterols from pumpkin seed oil included optimization of processing parameters while maintaining the formation of desirable sensory-active compounds.

The adaptation of bacteria involved in anaerobic ammonium oxidation (anammox) to low temperatures will enable more efficient removal of nitrogen from sewage across seasons. At lower temperatures, bacteria typically tune the synthesis of their membrane lipids to promote membrane fluidity. However, such adaptation of anammox bacteria lipids, including unique ladderane phospholipids and especially shorter ladderanes with absent phosphatidyl headgroup, is yet to be described in detail. We investigated the membrane lipids composition (UPLC-HRMS/MS) and dominant anammox populations (16S rRNA gene amplicon sequencing, Fluorescence in situ hybridization) in 14 anammox enrichments cultivated at 10-37 °C. "Candidatus Brocadia" appeared to be the dominant organism in all but two laboratory enrichments of "Ca. Scalindua" and "Ca. Kuenenia". At lower temperatures, the membranes of all anammox populations were composed of shorter [5]-ladderane ester (reduced chain length demonstrated by decreased fraction of C20/(C18 + C20)). This confirmed the previous preliminary evidence on the prominent role of this ladderane fatty acid in low-temperature adaptation. "Ca. Scalindua" and "Ca. Kuenenia" had distinct profile of ladderane lipids compared to "Ca. Brocadia" biomasses with potential implications for adaptability to low temperatures. "Ca. Brocadia" membranes contained a much lower amount of C18 [5]-ladderane esters than reported in the literature for "Ca. Scalindua" at similar temperature and measured here, suggesting that this could be one of the reasons for the dominance of "Ca. Scalindua" in cold marine environments. Furthermore, we propose additional and yet unreported mechanisms for low-temperature adaptation of anammox bacteria, one of which involves ladderanes with absent phosphatidyl headgroup. In sum, we deepen the understanding of cold anammox physiology by providing for the first time a consistent comparison of anammox-based communities across multiple environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

CE represents a very powerful separation tool in the area of chiral separations. CD-mediated chiral CE is a continuously flourishing technique within the frame of the electromigration methods. In this review, a brief overview of the synthetic procedures leading to modified CDs is provided first. Next, selected aspects related to the utilization of CDs in chiral CE are discussed specifically in the view of recently published data. Advantages of CDs and basic principles of chiral CE are remained. The topic of the determination of binding constants is touched. Particular attention is paid to the effort aiming at better understanding of the molecular level of the enantiorecognition between CDs and the analyte in the solution. Powerful approaches extensively utilized in this field are NMR, molecular modeling, and computer simulations. Then, a summary of applications of CDs in the CE enantioseparations is given, covering years 2008-2013. Finally, the general trend of modified CDs use in separation science is statistically evaluated., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work documents the influence of the position of single carboxymethyl group on the β-cyclodextrin skeleton on the enantioselectivity. These synthesized monosubstituted carboxymethyl cyclodextrin (CD) derivatives, native β-cyclodextrin, and commercially available carboxymethyl-β-cyclodextrin with degree of substitution approximately 3 were used as additives into the BGE consisting of phosphate buffer at 20 mmol/L concentration, pH 2.5, and several biologically significant low-molecular-mass chiral compounds were enantioseparated by CE. The results indicate that different substituent location on β-cyclodextrin skeleton has a significant influence on the enantioseparation of the investigated enantiomers. The enantioselectivity of 2(I)-O-regioisomer was better than with native β-cyclodextrin. Comparable results to native β-cyclodextrin were obtained for 6(I)-O- regioisomer and the enantioselectivity of 3(I)-O-regioisomer was even worse than with native β-cyclodextrin. Commercially available derivative of CD provides better resolutions than the monosubstituted carboxymethyl CD derivatives for most of the investigated analytes., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)