紫外線輻射照射皮膚後，會造成皮膚老化、產生皺紋、以及黑色素沉澱等變化。長時間暴露於紫外線輻射下，更會增加罹患皮膚癌的風險。因此，防曬保養品成了保護皮膚對抗紫外線輻射的一種重要工具。本研究的目的是篩選出對紫外線輻射具有耐受性的土壤菌株，用以研發新的抗紫外線輻射防曬商品。在55 個受測的土壤樣品中，有一個樣品含有紫外線輻射耐受性的菌群；接著，在此菌群中隨機挑選3 個單一的菌落，培養後進行菌種鑑定。經由比對其16S rRNA 基因序列，發現這3 個菌株均與假單胞桿菌屬的細菌非常相似（99 % 相似度）。親源關係分析顯示此3 個菌株與假單胞桿菌屬的螢光假單胞桿菌（Pseudomonas fluorescens）分在同一群。因而，將此具有紫外線輻射耐受性的菌株命名為Pseudomonas sp. UVT8。未來，可進一步探討Pseudomonas sp. UVT8 對抗紫外線輻射傷害的機制，並評估其作為新的防曬商品的潛力。

Ultraviolet (UV) radiation can cause skin aging, wrinkling, and pigmentation. Prolonged exposure to UV radiation increases the risk of skin cancer. Sunscreen products, therefore, have become an important tool for protection skin damage resulting from exposure to UV light. The aim of this study was to discover soil bacteria which are resistant to UV-dependent damages and can be used for developing new sunscreen products against UV radiation. One out of 55 soil samples contained a group of bacteria which have tolerance to UV radiation. Three randomly selected
isolates from this group of bacteria were subjected to species identification. The results based on 16S rRNA gene sequences showed that all three isolates are similar to Pseudomonas (99% similarity). Phylogenetic analysis demonstrated that these three isolates were clustered with Pseudomonas fluorescens. Therefore, this UV-radiationtolerance bacterium was named as Pseudomonas sp. UVT8. It is worthy to further investigate the mechanism of UV- radiation-tolerance of Pseudomonas sp. UVT8, and to evaluate Pseudomonas sp. UVT8 as a new potential sunscreen product.