| Abstract: | 本研究主要探討香蕉生產過程中的廢棄物偽莖嫩芯，其基本的機能特性和不同處理方式對其之影響。分成三個部分進行實驗，第一部分探討四種前處理方式 (冷凍乾燥、熱處理後凍乾、榨汁後凍乾及熱處理後榨汁凍乾) 處理香蕉偽莖嫩芯，再以不同極性溶劑 (水、95% 乙醇、丙酮、乙酸乙酯及正己烷) 萃取，分析不同前處理條件對不同溶劑之香蕉偽莖嫩芯萃取物中抗氧化能力與活性物質含量變化之影響；第二部分為不同乾燥溫度 (冷凍乾燥、50℃、75℃及100℃)與時間 (0 - 72小時)之處理對香蕉偽莖嫩芯之抗氧化活性變化，以確定其最適乾燥條件；第三部分將 100℃ 熱風乾燥香蕉偽莖嫩芯萃出物進行分離純化，盼能建立加熱對其抗氧化能力變化之相關資訊，提供相關研究及產品研發加工之參考。結果顯示最佳的萃取條件為殺菁榨汁後凍乾並以 95% 乙醇萃取之樣品，其總酚、類黃酮含量及抗氧化活性較佳。進一步將香蕉偽莖嫩芯用不同溫度乾燥處理後發現，100℃ 熱風乾燥者有最佳的抗氧化活性，且隨著乾燥時間的增加，總酚、總類黃酮及抗氧化能力有上升的趨勢，但乾燥 36 小時後，總酚、類黃酮含量及抗氧化活性差異不大，因此選擇最佳乾燥條件為100℃乾燥 36 小時。香蕉偽莖嫩芯經液-液萃取後，無論是冷凍乾燥還是 100℃ 乾燥處理，其總酚、總類黃酮含量、抗氧化活性及抑制 LDL 氧化，皆為乙酸乙酯層之區分物效果最好，並進一步將乙酸乙酯層區分物經 Sephadex LH-20 管柱層析後發現，無論是冷凍乾燥處理亦或是 100℃ 乾燥處理，延遲 LDL 氧化時間在兩種乾燥處理皆為第六區分物之延遲效果最佳，在 HPLC 分析發現，其酚類化合物含有 ⍴-coumaric acid。The study mainly investigated the effects on functionalities of the wastes of pseudo-stem tender core after banana harvested by the various treatments. The experiments were divided into three parts; the first part was studied on the effects in changes of antioxidative capacities and functional compounds of pseudo-stem tender core by 4 pre-treatments (Un-treated, Heated, Squeezed, and Heated-and-Squeezed) and 5 solvents (Water, 95% Ethanol, Acetone, Ethyl acetate, and n-Hexane). In the second part, the pseudo-stem tender core was dried at various temperatures (Frozen-dried, 50℃, 75℃, and 100℃) and dried time (0-72 h) to investigated the changes in antioxidative activities of pseudo-stem tender core, and then to figure out the optimal dried condition. The third part was that the extracts of banana pseudo-stem tender core by frozen-dried and 100oC-dried were isolated and purified to establish the information about the relation between heated treatment and antioxidant capacities, and the information could be provided to relevant research and product development as references. The results showed that the more total phenolic content and flavonoid content, and better antioxidative activities of tender core could be obtained in the better condition (by heated and squeezed, and extracted with 95% ethanol). Pseudo-stem tender core of banana was further processed by dried at various temperatures, and the better antioxidative activities could be obtained at 100oC-dried. Total phenolic content, total flavonoid content and antioxidative activities increased as dried time increased at 100oC-dried, and antioxidative activities were not significant difference after dried for 36h. Therefore, tender core dried at 100oC for 36h was the optimal dried condition. After liquid-liquid partition, the ethyl acetate fractions of both frozen-dried and 100oC-dried had the higher total phenolic content, higher total flavonoid content, better antioxidant activities and longer lag time of inhibition LDL oxidation. The ethyl acetate fraction of frozen-dried and 100oC-dried were separated by through Sephadex LH-20 column, respectively and the total phenolic content, total flavonoid content, DPPH radical scavenging activity and lag time of inhibition LDL oxidation were better in the 6 fraction of both treatments. ⍴-Coumaric acid could be found by HPLC. |
