研究生：楊惠婷 Yang, Hui-Ting
指導教授：廖遠東 Liaw, Ean-Tun
本研究目的係評估手掌參(Gymnadenia conopsea)多醣體調節血脂及其水解產物抗氧化活性之探討。首先利用熱水萃取，經乙醇沉澱後，獲取手掌參粗多醣，再以酵素水解得到不同分子量之水解產物，且用分子篩管柱(TSK GEL G3000)分析其手掌參多醣及水解產物分子量之大小。結果顯示以0.8U Laminarinase在37℃、10分鐘及1U cellulase在37℃、10分鐘水解反應條件下，其水解產物分子量分別為12000 Da與22800 Da。而以Laminarinase酵素水解後之還原醣含量為89.20 mg/g，均較未水解前之多醣高2.5倍；在清除DPPH自由基能力方面，以laminarinase水解的手掌參多醣水解產物清除能力較未水解多醣提升2倍。然螯合亞鐵離子能力測定，以cellulase酵素水解產物效果最佳；而在還原力及硫氰酸鐵法方面則各組並無顯著差異。再者，以雄性倉鼠(male hamster)作為實驗動物模式，經餵食多醣體十週後，結果顯示管餵手掌參多醣之低、中及高劑量具有調降血清中三酸甘油酯之功效，其效果分別為42.79%、48.72% 及53.8%；而調降膽固醇方面介於21.78%~24.68%，在LDL方面下降幅度分別為46.3%、45.66%、44.59%，且LDL/HDL 比值易有顯著降低。由上述結果得知手掌參多醣對於高膽固醇飲食所引起之脂質異常具有改善作用。
The major objective of the current study was assessment of Gymnadenia conopsea and its hyperlipidemia effects on hamster. Gymnadenia conopsea, as a subject material was employed in the current study. The sample extracted by hot water and followed by ethanol precipitation and then a crude polysaccharide was obtained for further study. Various hydrolysates with different size were prepared by enzymatic hydrolysis. The multi-molecular weight was analyzed by size exclusion chromatography (SEC) using TSK GEL G3000 column. The results indicated that the MW 12000 and MW 22800 were determined and obtained by using 0.8 U of laminarinase at 37℃ for 10 minutes and 1.0 U of Cellulase at 37℃ for 10 minutes, respectively. Reducing sugar compounds, 89.20 mg/g, were measured and they showed two times higher compared to those of crude polysaccharide before hydrolysis. Moreover, two-fold increase of DPPH scavenging activity of laminarinase hydrolysate derived from Gymnadenia conopsea was observed compared to intact polysaccharide. On chelating activity, cellulase hydrolysates demonstrated the highest effect. In reducing power and the ferric thiocyanate method, no significant difference was found among groups. Furthermore, animal study of anti-hyperlipidemia was conducted and verified by employing Male Hamster as an animal model. The results illustrated that intake low, medium and high dosage of Gymnadenia conopsea polysaccharides can reduce serum triglyceride by 42.79%, 48.72% , 53.8% respectively, after 10 weeks experimental diet period. Total cholesterol levels were significantly lower about 21.78%~24.68%, and the LDL-C levels were decreased by 46.3%, 45.66%, 44.59%, respectively. Consequently, LDL/HDL ratio were significantly reduced. Conclusively, Gymnadenia conopsea polysaccharide of the protective effect against lipid modulation in hamster fed high-fat diet was depicted under specified conditions.
Keywords：Gymnadenia conopsea, Cholesterol, Triglyceride