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Medicinal phytochemicals, such as artemisinin and taxol, have impacted the world, and hypericin might do so if its availability issue could be addressed. Hypericin is the hallmark component of Saint John's wort (Hypericum perforatum L.), an approved depression alleviator documented in the US, European, and British pharmacopoeias with its additional effectiveness against diverse cancers and viruses. However, the academia‐to‐industry transition of hypericin remain hampered by its low in planta abundance, unfeasible bulk chemical synthesis, and unclear biosynthetic mechanism. Here, we present a strategy consisting of the hypericin‐structure‐centered modification and reorganization of microbial biosynthetic steps in the repurposed cells that have been tamed to enable the designed consecutive reactions to afford hypericin (43.1 mg L−1), without acquiring its biosynthetic knowledge in native plants. The study provides a synthetic biology route to hypericin and establishes a platform for biosustainable access to medicinal phytochemicals. [ABSTRACT FROM AUTHOR]

A fluorophilic fluorescent probe based on a perfluoroalkyl‐substituted bis(binaphthyl) compound was designed and synthesized. It displayed a highly enantioselective fluorescence response toward structurally diverse amino acids in a biphasic fluorous/aqueous system with enantiomeric fluorescent enhancement ratio (ef; ΔID/ΔIL) values up to 45.2 (histidine). It can be used to determine the enantiomeric compositions of amino acids and also allows the amino acid enantiomers to be visually discriminated. NMR and mass‐spectroscopic investigations provided insights into the observed high enantioselectivity. This biphasic fluorescent recognition was used to determine the enantiomeric composition of the crude phenylalanine products generated by an enzyme‐catalyzed asymmetric hydrolysis under various reaction conditions. The fluorous‐phase‐based fluorescence measurement under the biphasic conditions was able to minimize the interference of other reaction components and thus has potential in asymmetric reaction screening. [ABSTRACT FROM AUTHOR]