Isolation of skin photo-protective metabolites from bamboo (Phyllostachys pubescens) shoot.

Abstract

UV induced skin aging also known photo-aging generally occurred due to accumulation of cellular damage brought on by external causes. Photoaging is the prime consequence of the repeated exposure of UVB. We focused on the isolation and identification of the UVB photo-protective metabolites from bamboo shoot (Phyllostachys pubescens). As the edible part, bamboo shoot is widely recognized and has been studied to evaluate different biological activities but evaluation of the UVB photo-protective activity on skin fibroblast is not done yet. Isolation of UVB photo-protective metabolites on human dermal fibroblast cells (NHDF-Ad) of bamboo shoot methanolic extract yields three compounds. The structure of these three compounds was determined by using NMR and HR-ESI-MS as 2,3-dihydroxypropyl 9-octadecenoate (1) 2,3-dihydroxypropyl tridecanoate (2) and 2,3-dihydroxypropyl undecanoate (3). These isolated compounds were also tested for the UVB photo-protection. Isolated compounds showed no obvious cytotoxicity until the concentration 10 μg/mL. Among all isolated compounds, compound-1 showed the strongest photo-protective activity. All these isolated compounds at different concentrations, increased the cell viability of UVB irradiated NHDF-Ad cells without any cytotoxicity. The crude extract and the isolated compounds were tested for anti-inflammatory activity in mouse leukemic monocyte (RAW 264) cells and all of them reduced NO production at non-cytotoxic concentration and reduced the expression of the inflammatory genes cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). The present study is the first to explore the isolation and identification of UVB photo-protective metabolites from bamboo shoot and the contributory compounds to be further utilized in the cosmeceutical industry.