Preparation and cytoprotective effects of media milled goji (Lycium barbarum)
| Autor: | Nien-Chen Lin, 林念蓁 |
|---|---|
| Rok vydání: | 2011 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 100 Nanomaterials have been applied in various industries, in which food nanomaterials are rapidly developed and employed worldwide. In this study, we use goji (Lycium barbarum) as a material, focusing on the intake of whole materials, and exploring the potential of development of health food product. Media milling was employed to prepare nano/submicron scaled goji. The number average diameter of goji was reduced to 100 nm after 90-min media milling. The higher surface negative charge might be attributed to the better particle dispersion and stability. The extraction efficacy of soluble dietary fiber, crude polysaccharides, total carotenoids and beta-carotene were elevated by size reduction. For the safety concern, we use cell culturing test to observe the cell viability. The cell viabilities of rat normal small intestinal cell line IEC-6, human colon adenocarcinoma cell line Caco-2 and primary mouse splenocytes did not directly influenced by media milling. The bioavailability of zeaxanthin was revealed by biodistribution of SD rats. Intake of media milled goji waa resulted in the increase of zeaxanthin concentration in serum, livers and spleens. Oligomicroarray and QPCR were revealed that three genes related to cell survival, TNF-alpha, NF-kappaB and Bcl-2 were up regulated, and two genes related to pro-apoptosis, APAF-1 and Caspase3 were down regulated by goji.Western blotting results also confirmed the effects of regulation on protein expression levels of those genes. Cytoprotective activities and mechanisms were further investigated in vitro. Media-milled goji significantly reduced camptothecin-induced cell death and caspase-3 activity of mouse primary splenocytes, nevertheless, it did not induce uncontrolled cell proliferation. It suggested that the coordination between TNF-αand NF-κB induce downstream anti-apoptotic protein Bcl-2 expression, further down regulated pro-apoptotic protein Caspase3 and Apaf-1 expression. For the neuroprotective effects, both samples dose dependently prevented PC12 cells from apoptosis caused by serum deprivation. NF-kappaB acts as an importantsurvival factor was revealed by NF-kappaB specific double strand oligonucleotidetreatment and Western blotting. Serum-deprived PC12 cell viability and NF-kappaB p50/p65protein expression were significantly elevated by media-milled goji. Activation of NF-kappaB by media-milled goji seemed to beresulted in better cell viabilities. In conclusion, reduced particle size, large surface area, more negative charge and better particle stability of media-milled goji were helpful for extraction of bioactive compounds and zeaxanthin bioavailability, further be attributed to the enhanced cytoprotective and neuroprotective activities. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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