title: Natural products as photoprotection.
abstract: The rise in solar ultraviolet radiation on the earth's surface has led to a depletion of stratospheric ozone over recent decades, thus accelerating the need to protect human skin against the harmful effects of UV radiation such as erythema, edema, hyperpigmentation, photoaging, and skin cancer. There are many different ways to protect skin against UV radiation's harmful effects. The most popular way to reduce the amount of UV radiation penetrating the skin is topical application of sunscreen products that contain UV absorbing or reflecting active molecules. Based on their protection mechanism, the active molecules in sunscreens are broadly divided into inorganic and organic agents. Inorganic sunscreens reflect and scatter UV and visible radiation, while organic sunscreens absorb UV radiation and then re-emit energy as heat or light. These synthetic molecules have limited concentration according to regulation concern. Several natural compounds with UV absorption property have been used to substitute for or to reduce the quantity of synthetic sunscreen agents. In addition to UV absorption property, most natural compounds were found to act as antioxidants, anti-inflammatory, and immunomodulatory agents, which provide further protection against the damaging effects of UV radiation exposure. Compounds derived from natural sources have gained considerable attention for use in sunscreen products and have bolstered the market trend toward natural cosmetics. This adds to the importance of there being a wide selection of active molecules in sunscreen formulations. This paper summarizes a number of natural products derived from propolis, plants, algae, and lichens that have shown potential photoprotection properties against UV radiation exposure-induced skin damage.
authors.affiliation: School of Cosmetic Science, Mae Fah Luang University, Muang, Chiangrai, Thailand.
authors.forename: Nisakorn
authors.initials: N
authors.lastname: Saewan
authors.forename: Ampa
authors.initials: A
authors.lastname: Jimtaisong
mesh_terms: D000818:Animals; D001688:Biological Products / Q000627:therapeutic use*; D004487:Edema / Q000517:prevention & control; D004890:Erythema / Q000517:prevention & control; D006801:Humans; D017495:Hyperpigmentation / Q000517:prevention & control; D012867:Skin / Q000187:drug effects* / Q000528:radiation effects*; D015595:Skin Aging / Q000187:drug effects; D012878:Skin Neoplasms / Q000517:prevention & control; D013471:Sunburn / Q000517:prevention & control; D013472:Sunlight / Q000009:adverse effects*; D013473:Sunscreening Agents / Q000627:therapeutic use*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D001688:Biological Products; D013473:Sunscreening Agents
keywords: UV radiation; natural product; photoprotection; sunscreens