The aim of this study was to investigate changes in the weight of Zophobas morio larvae and mass of polystyrene foam when the larvae were fed polystyrene for 27 days. Fourier-transform infrared (FTIR) spectrometry was used to determine whether the polystyrene was broken down by the larvae. Forty Z. morio larvae (four replicates with 10 larvae per replicate) were reared in a chamber under controlled conditions with polystyrene foam blocks as their sole diet. The weight of the Z. morio larvae and mass of the polystyrene foam decreased as a function of time. The average weight of the larvae and mass of the polystyrene foam blocks decreased by 16.3 and 6.5%, respectively, over the 27-day period. The FTIR spectrum of Z. morio larvae fed with polystyrene foam did not reveal the unique peaks associated with polystyrene. In conclusion, this study suggests the possibility of using Z. morio larvae as a management technology for degrading waste plastics without a negative environmental effect. Key words : FTIR spectra, plastic biodegradation, polystyrene foam, Zophobas morio larvae.

Astaxanthin, a natural antioxidant carotenoid, has been thought to provide health benefits by decreasing the risk of oxidative stress?related diseases. In the present study, we investigated the effect of an astaxanthin during the autophagic cell death induced by bisphenol A (BPA) which is known major environmental pollutants. We found that astaxanthin significantly blocked the autophagic cell death via inhibition of intracellular Reactive Oxygen Species (ROS) in normal human dermal fibroblasts. Astaxanthin significantly inhibited the phosphorylation mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) responsible for the expression of LC3-II and Beclin-1 in BPA-treated normal human dermal fibroblasts. We suggest that astaxanthin blocks autophagic cell death induced by BPA via the inhibition of ROS-mediated signaling events in human dermal fibroblasts.

Kaempferol (3,4',5,7-tetrahydroxyflavone), a flavonoid found in beans, broccoli, garlic, etc., has been used in natural medicine as an anti-inflammatory and antioxidant. This experiment was carried out to evaluate the anti-apoptotic effect of kaempferol in 12-O-tetradecanoylphorbol 13-acetate (TPA)-treated Normal Human Dermal Fibroblast (NHDF). Kaempferol inhibited the production of intracellular Reactive Oxygen Species (ROS) induced by TPA in NHDF. Kaempferol significantly blocks the phosphorylation of extracellular signal-regulated kinase responsible for the activation of nuclear factor-kappa B. In addition, kaempferol significantly attenuated the expression of Bax and cleaved caspase-3 as regulated by the phosphorylation of nuclear factor-kappa B during its blockage of TPA-induced apoptotic cell death. These findings suggest that kaempferol protects the apoptotic signaling pathway induced by TPA through modulating intracellular ROS in NHDF.

Astaxanthin, a natural carotenoid component of shrimp, has been used as a food additive for the treatment of various diseases, but a functional role of Astaxanthin Nanosphere (AN) in the regulation of intestinal mucin (Muc) 2 production during bacterial infection has not described yet. In this study, we have investigated the effect of AN prepared from astaxanthin during Muc2 repression elicited by the Gram-negative bacterium V. vulnificus in human gastrointestinal epithelial (HT-29) cells. AN significantly inhibited the level of ROS production and PKC activation in recombinant protein (r) VvpE-stimulated HT-29 cells. Moreover, AN inhibited the PKC-mediated phosphorylation of extracellular signal-regulated kinase and nuclear factor-kappa B responsible for region-specific hypermethylation in the Muc2 promoter in rVvpE-treated HT-29 cells. In the mouse models of V. vulnificus infection, treatment with AN maintained the level of Muc2 expression in the intestine. On the basis of these results, we suggest that AN blocks the hypermethylation of the Muc2 promoter to restore the level of Muc2 production in HT-29 cells infected with V. vulnificus.

Curcumin, a hydrophobic polyphenol derived from turmeric, has been used a food additive and as a herbal medicine for the treatment of various diseases. In the present study, we found the functional role of a nanosphere loaded with curcumin (CN) in the promotion of the motility of human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) during the wound closure. We found that the efficacy of hUCB-MSCs migration induced by CN was 1000-fold higher than that of curcumin powder. CN significantly increased the motility of hUCB-MSCs by activating c-Src, which is responsible for the phosphorylation of protein kinase C (PKC) and extracellular signal-regulated kinase (ERK). CN induced the expression levels of α-actinin-1, profilin-1 and filamentous-actin, as regulated by the phosphorylation of nuclear factor-kappa B during its promotion of cell migration. In a mouse skin excisional wound model, we found that transplantation of UCB-MSCs pre-treated with CN enhances wound closure, granulation, and re-epithelialization at mouse skin wound sites. These results indicate that CN is a functional agent that promotes the mobilization of UCB-MSCs for cutaneous wound repair.