Title: UV-A sunscreen from red algae for protection against premature skin aging Author/s:: Schmid Daniel, Schü rch Cornelia and Zü lli Fred, Mibelle AG Biochemistry Abstract: In summer time at the beach, people know that they have to protect themselves with sun creams against sunburn. But sunlight affects our skin every day of the year, which finally leads to premature skin aging, also called photo- aging. This is shown by the fact that permanent exposed skin sites, such as the face and hands show in general more aging signs than covered skin. The principal etiologic factor of premature skin aging is UV-A. Unlike UV-B, UV-A is not dependent on time of day or season, and it penetrates rather well through clouds and window glass. Skin therefore need protection against daily exposure to UV-A. Cosmetic ingredients intended for everydady use should be absolutely safe. Mycosporine-like amino acids are UV-A sunscreens produced by certain algae, corals and zooplankton. We have found the red alga Porphyra umbilicalis, a traditional sea vegetable better known as ‘Nori’, to be a rich source of mycosporine-like amino acids. A preparation of mycosporine-like amino acids in liposomes was tested in a study on UVA-induced skin aging. In this study a UV-A dose was applied that corresponds to everyday situations in central Europe. Comparing skin lipid oxidation and skin aging parameters such as elasticity, wrinkle depth and roughness, a cream with liposomal mycosporine-like amino acids performed as well as a cream with a synthetic UV-A sunscreen. Title: In vivo photoprotective effects of cosmetic formulations containing UV filters, vitamins, Ginkgo biloba and red algae extracts Author/s: Mercurio DG, Wagemaker TA, Alves VM, Benevenuto CG, Gaspar LR, Maia Campos PM Abstract: The aim of this study was to assess the photoprotective effects of cosmetic formulations containing UV filters, red algae, Porphyra umbilicalis, extracts and combinations of the extract with vitamins and Ginkgo biloba through the use of in vivo preclinical studies. For this study, 4 groups of 4 hairless mice each were treated with topical formulations applied on the dorsum for 5 days as follows: group 1 - control (no treatment); group 2 - application of the formulation F (sunscreen formulation containing only UV filters); group 3 - application of the formulation FA (sunscreen formulation with red algae extract); and group 4 - application of the formulation FVGA (sunscreen formulation with red algae extract, G. biloba and vitamins A, C and E). The effects of these formulations were evaluated by determining the transepidermal water loss (TEWL) and erythema index. Apoptosis was detected by immunohistochemical staining with anti-p53 and anti-caspase-3 antibodies. The results showed that the formulations protected the skin from erythema when exposed to UV radiation. The group that received the formulation FVGA presented a greater TEWL than did the other groups, suggesting that this formulation was involved in cell renewal. Immunohistochemical analysis showed that UV radiation caused an increase in the expression of p53 and active caspase-3, confirming that the damage caused by UV radiation exposure led to apoptosis. The application of all formulations studied resulted in a statistically significant reduction in the expression of p53 and caspase-3, with a more pronounced effect observed following treatment with FA. In conclusion, extracts from the red algae P. umbilicalis could be considered effective ingredients to be used in sunscreen formulations. The combination of vitamins A, E, C and G. biloba along with red algae extracts can improve significantly the performance of the sunscreens, preventing UVinduced DNA damage and inflammation. Thus, they should be considered an interesting combination for an effective photoprotective formulation with anti-aging properties. Title: The isolation of prophyra-334 from marine algae and its UV-absorption behavior Author/s: Zhang Zhaohui, Gao Xin, Yuri Tashiro, Shingo Matsukawa, Hiroo Ogawa Abstract: Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae (dried laver). It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200–400 nm. The absorption maximum wavelength of prophyra-334 is at 334 nm, so defined the name. The molar extinction coefficient (ε) of prophyra-334 in aqueous solution at 334 nm wavelength is 4.23×104. The absorption of prophyra-334 in organic solvents differs in aqueous solutions. In polar organic solvents, the absorption maximum wavelength of prophyra334 has a slight shift toward longer wavelength compared with that in pure water. On the contrary, in inert non-polar organic solvents, the absorption maximum wavelength and the shape of absorption spectra of prophyra-334 are changed. The effects of organic solvents on prophyra-334 stability suggested that: (1) the absorbance of prophyra-334 in water is generally constant at temperature of 60°C in 24 h, meaning that prophyra-334 is quite stable in water; (2) the absorbance of prophyra-334 in ethanol and hexane decreases at the same condition. The stability of prophyra-334 in organic solvents is less than that in aqueous solution. In benzene, the prophyra-334 is very instable. Title: Cyanobacterial metabolites as a source of sunscreens and moisturizers: a comparison with current synthetic compounds Author/s: Peyman Derikvand, Carole A. Llewellyn & Saul Purton Abstract: The recognition that ultraviolet radiation has harmful effects on the skin has led to the commercial development of inorganic and synthetic organic UV filters that can reduce the negative effects of exposure to sunlight. In addition, moisturizing chemicals are extensively used in personal care products to improve the ability of skin to retain water. Whilst current UV filter and moisturizing chemicals have clear beneficial qualities, they may also have adverse effects such as contact sensitivity, oestrogenicity and even tumorigenic effects on human skin. Furthermore, the accumulation of these chemicals in the aquatic environment could be potentially harmful. Consequently, there is interest in exploiting safer alternatives derived from biological sources, especially from photosynthetic organisms such as cyanobacteria which have developed mechanisms for coping with high UV irradiation and desiccation. In order to overcome the detrimental effects of UV radiation, these microorganisms produce UV screening compounds such as mycosporine-like amino acids and scytonemin, which are good candidates as alternatives to current synthetic UV filters. In addition, extracellular substances produced by some extremophilic species living in hyper-arid habitats have a high water retention capacity and could be used in cosmetic products as moisturizers. In this review, we present an overview of the literature describing the potential of cyanobacterial metabolites as an alternative source for sunscreens and moisturizers. Title: Exploiting Mycosporines as Natural Molecular Sunscreens for the Fabrication of UV-Absorbing Green Materials Author/s: Susana C. M. Fernandes, Ana Alonso-Varona§, Teodoro Palomares, Verónica Zubillaga, Jalel Labidi and Vincent Bulone Abstract: Ultraviolet radiations have many detrimental effects in living organisms that challenge the stability and function of cellular structures. UV exposure also alters the properties and durability of materials and affects their lifetime. It is becoming increasingly important to develop new biocompatible and environmentally friendly materials to address these issues. Inspired by the strategy developed by fish, algae, and microorganisms exposed to UV radiations in confined ecosystems, we have constructed novel UV-protective materials that exclusively consist of natural compounds. Chitosan was chosen as the matrix for grafting mycosporines and mycosporine-like amino acids as the functional components of the active materials. Here, we show that these materials are biocompatible, photoresistant, and thermoresistant, and exhibit a highly efficient absorption of both UV-A and UV-B radiations. Thus, they have the potential to provide an efficient protection against both types of UV radiations and overcome several shortfalls of the current UV-protective products. In practice, the same concept can be applied to other biopolymers than chitosan and used to produce multifunctional materials. Therefore, it has a great potential to be exploited in a broad range of applications in living organisms and nonliving systems.
