In this work, a new aerobic route is introduced for the selective oxidation of a variety of aromatic and aliphatic alcohols to the corresponding aldehyde and ketone derivatives by molecular oxygen in the presence of free base porphyrins and metalloporphyrins as sensitizers using white light or sunlight in an organic solvent. The method shows a wide scope, exhibits chemoselectivity and proceeds under mild reaction conditions. The resulting products are obtained in good conversions in a reasonable time.

Lipid oxidation is a complex process in muscle-based foods (red meat, poultry and fish) causing severe quality deterioration, e.g., off-odors, discoloration, texture defects and nutritional loss. The complexity of muscle tissue -both composition and structure- poses as a formidable challenge in directly clarifying the mechanisms of lipid oxidation in muscle-based foods. Therefore, different in vitro model systems simulating different aspects of muscle have been used to study the pathways of lipid oxidation. In this review, we discuss the principle, preparation, implementation as well as advantages and disadvantages of seven commonly-studied model systems that mimic either compositional or structural aspects of actual meat: emulsions, fatty acid micelles, liposomes, microsomes, erythrocytes, washed muscle mince, and muscle homogenates. Furthermore, we evaluate the prospects of stem cells, tissue cultures and three-dimensional printing for future model system development. Based on this reviewing of oxidation models, tailoring correct model to different study aims could be facilitated, and readers are becoming acquainted with advantages and shortcomings. In addition, insight into recent technology developments, e.g., stem cell- and tissue-cultures as well as three-dimensional printing could provide new opportunities to overcome the current bottlenecks of lipid oxidation studies in muscle.

A homogeneous photocatalytic reaction cascade for the stepwise biomimetic oxidation of alcohols to form either aldehydes or alternatively carboxylic acids is presented. The system is based on robust and abundant materials and efficiently utilizes dioxygen as a clean and sustainable oxidant. Photoassisted substrate transformation occurs upon exposure to visible light (<620 nm) or sunlight. The pH-dependent photoredox mechanism of the sensitizer can be reversibly switched between two different selectivity patterns to control the desired product formation.