title: Hydrogen bond dynamics governs the effective photoprotection mechanism of plant phenolic sunscreens.
abstract: Sinapic acid derivatives are important sunscreen species in natural plants, which could provide protection from solar UV radiation. Using a combination of ultrafast excited state dynamics, together with classical molecular dynamics studies, we demonstrate that there is direct coupling of hydrogen bond motion with excited state photoprotection dynamics as part of the basic mechanism in solution. Beyond the intra-molecular degree of freedom, the inter-molecular motions on all timescales are potentially important for the photochemical or photophysical events, ranging from the ultrafast hydrogen bond motion to solvent rearrangements. This provides not only an enhanced understanding of the anomalous experimental spectroscopic results, but also the key idea in the development of sunscreen agents with improved photo-chemical properties. We suggest that the hydrogen bond dynamics coupled excited state photoprotection mechanism may also be possible in a broad range of bio-related molecules in the condensed phase.
authors.affiliation: Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, P.R. China. dulikai@mail.hzau.edu.cn gaojun@sdu.edu.cn.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, P.R. China. dulikai@mail.hzau.edu.cn gaojun@sdu.edu.cn.
authors.forename: Likai
authors.identifier: 0000-0002-3198-276X
authors.initials: L
authors.lastname: Du
authors.affiliation: Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, P. R. China.
authors.forename: Zhenggang
authors.initials: Z
authors.lastname: Lan
authors.affiliation: Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, P.R. China. dulikai@mail.hzau.edu.cn gaojun@sdu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Gao
mesh_terms: D003373:Coumaric Acids / Q000737:chemistry* / Q000378:metabolism; D006860:Hydrogen Bonding; D007536:Isomerism; D000432:Methanol / Q000737:chemistry; D056004:Molecular Dynamics Simulation; D010944:Plants / Q000737:chemistry* / Q000378:metabolism; D013473:Sunscreening Agents / Q000737:chemistry* / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D003373:Coumaric Acids; D013473:Sunscreening Agents; C073734:sinapinic acid; D000432:Methanol