- 學位論文
以微膠囊包覆技術開發改良蝦紅素之安定性最佳處方之研究
The study of the optimal microencapsulation formulation for improving the stability of Astaxanthin
摘要
本研究之目的在於研究以微膠囊包覆技術開發改良蝦紅素（Astaxanthin）之安定性表現最佳之處方。蝦紅素為一可從天然來源提煉出或合成而來之強抗氧化劑。目前廣泛應用於漁業、飼養業等，許多研究都指出其對癌症、心血管疾病及其他與氧化相關之疾病皆有一定幫助。但其安定性表現甚差，十分易受外界因子影響產生降解或行異構化反應，因此希望能藉由改善安定性來增加使用效能。 而微膠囊包覆技術目前應用於包裹如：藥物、細胞、酵素等小物質來增加其安定性；除了能阻隔外界環境因子對物質產生傷害外，此技術尚有矯味及緩釋之功效。製備方法有許多種，此次主要選擇使用擠壓法來做處方設計。微膠囊包覆技術主要是利用基質或外層膜層包覆來製備，而因使用天然聚合物當作材料有生體相容性高之優點，所以此次選擇使用藻酸鈉（Sodium alginate）當作主材料來製備。 本實驗為利用高效液相層析系統（HPLC）來做蝦紅素之定性定量分析，並針對外界環境因子：溫度、空氣、光線對蝦紅素可能造成的影響來做探討，再藉由調控微膠囊包覆技術之製程希望能獲得改善其安定性最佳處方，材料則主要為藻酸鈉及鈣離子來製備，在篩選處方方面則以成品粒子大小、成品重量、製程回收率以及外觀形態觀察來做比較。篩選處方後則再添加蝦紅素並以加速安定性實驗來考驗其對於改善安定性之效果。 使用高效液相層析系統實驗結果找到使用之分析條件為具有準確度及精密度之方法，而外界環境因子則以溫度影響最為劇烈。在實驗處方設計上也發現原料之間的比例會影響到產品的特性，尤以藻酸鈉及鈣離子濃度影響最大，在兩者濃度越低的情況下能製備出大小較小之微膠囊，但過低之藻酸鈉濃度也不易形成良好微膠囊之結構。而在加速安定性試驗測試下，經過三周常溫（25oC）及高溫（40oC）儲存，其中在高溫下四組Astaxanthin剩餘率達85%，其他組別則都超過90%；而在常溫下，所有組別都有90%以上之剩餘率。證實此一微膠囊劑型可有效提升Astaxanthin之安定性。
關鍵字
微膠囊,蝦紅素,擠壓法,安定性並列摘要
The purpose of the study is the development of microencapsulated formulation for improving the stability of the Astaxanthin. Astaxanthin is an antioxidant which could be artificially synthesized or extracted from natural resources and is broadly applied to aquaculture and pasturage industry. To date, numerous research indicated Astaxanthin can improve cardiovascular disease, oxidation-related disease, and cancer as an auxiliary treatment. Nevertheless, the stability of Astaxanthin is relatively bad, so that Astaxanthin could readily degrade or isomerizate without an ideal storage. It’s one of the technical difficulties we need to overcome. Once the stability enhance, the applicability of Astaxanthin will substantially advance. Nowadays, microencapsulation is well-developed for packaging materials up as cores isolated from the surrounding environment to gain the stability. For example, drugs, cells, and enzymes are common applied materials. Furthermore, it also provides additional effects of masking unpleasant tastes, odors and controlled-release. Several preparation methods were invented, such as spray-drying, fluidized bed coating, extrusion, emulsion phase separation, coacervation, layer-by-layer self-assembly, and microfluidic system. In this study, Astaxanthin is quantified and qualified by high-performance liquid chromatography. The stability of Astaxanthin would be optimized by controlling the conditions of steps of the microencapsulation preparation process. The formulation is prepared by calcium chloride and sodium alginate which is a member of nature polymers and possesses high biocompatibility. After comparing the size, weight, and morphology of the different formulation particles, we discover the lower the concentration of calcium ion and sodium alginate are, the smaller the particles size is. However, at the concentration of sodium alginate lower than 2%, the microcapsules begin to lose their smooth in appearance and uniformity in morphology. To the consideration above, some formulations are selected and examined the improvement in stability of Astaxanthin by conducting accelerated stability testing. After 3 weeks storage at 25oC and 40oC, the remaining contents of Astaxanthin of four sets at 40oC have reached 85%, other sets have exceeded 90%. On the other hand, at 25oC, all the formulations have exceeded 90% of content. These results inferred the Astaxanthin formulated by microencapsulation have better stability than the original.