| 摘要: | 本研究針對台灣三個品種（李林蕉、寶島蕉及台蕉五號）的成熟香蕉萃取物，進行保濕與抗氧化能力的研究，並進一步探究台灣種植面積及產量最大的品種-台蕉五號進行活性成分之追蹤，希望藉由本研究瞭解台灣三種香蕉萃取物所具備的皮膚改善效能，進而評估其成為皮膚保養品機能性原料的潛力。
本研究運用兩種溶劑（95%乙醇及二次水）進行萃取，分別獲得香蕉果皮、果肉之水萃物與95%乙醇萃取物，水萃液中加入五倍體積的95%乙醇以獲得其粗多醣萃取物。所有獲得之萃取物分別進行吸濕、保濕、清除DPPH•自由基、清除ABTS•+陽離子自由基、螯合亞鐵離子與抑制脂質過氧化等實驗。
在保濕方面，試驗結果顯示三個品種的香蕉果皮粗多醣及果肉粗多醣均具有與標準品（玻尿酸）相當或接近的保濕及吸濕效果；三種香蕉粗多醣含量，除了寶島蕉果肉粗多醣含量略高外，其他粗多醣含量均相當接近。
在抗氧化方面，香蕉水萃物清除DPPH•自由基能力均優於95%乙醇萃取物，其中以香蕉果皮萃取物的效果最佳，在1000 g/mL 時，果皮水萃物清除率皆達90%以上，清除能力由高至低依序為台蕉五號（93.8±0.4%）、寶島蕉（91.8±0.9%）及李林蕉（91.3±0.7%）；果皮乙醇萃取物清除率則均達80%以上，依序為寶島蕉（91.6±0.4%）、台蕉五號（80.8±0.9%）及李林蕉（80.1±0.7%）；而在香蕉果肉及粗多醣萃取物的部分，則以李林蕉果肉水萃物（88.9±0.5%）及李林蕉果肉粗多醣(51.7±1.0%）效果最佳。香蕉萃取物於100 g/mL 時，清除ABTS• + 自由基的能力，大致上以粗多醣 ﹥果皮﹥果肉，其中又以水萃物清除效果優於乙醇萃取物，且果肉粗多醣優於果皮粗多醣，清除率由高至低依序為，李林蕉果肉粗多醣（99.0±0.5%）﹥台蕉五號果皮水萃物（90.4±0.5%）﹥寶島蕉果皮水萃物（89.3±0.8%）﹥李林蕉果肉水萃物（71.3±0.3%）﹥寶島蕉果肉粗多醣（66.7±0.1%）﹥台蕉五號果肉粗多醣（62.8±1.1%）﹥寶島蕉果皮粗多醣（54.7±0.2%）。香蕉萃取物在2000g/mL時，螯合亞鐵離子的能力之結果顯示：果皮粗多醣 ﹥果肉粗多醣 ﹥果皮乙醇萃取物，在果皮粗多醣的部分，其效能以李林蕉（95.7±0.1%）﹥寶島蕉（93.6±0.5%）﹥台蕉五號（75.2±1.0%）；果肉粗多醣的部分則以台蕉五號（79.0±2.0%） ﹥李林蕉（59.1±0.8%） ﹥寶島蕉（58.3±2.0%）；而果皮乙醇萃取物，在螯合亞鐵離子的效能，則為李林蕉
（57.3±0.7%）﹥台蕉五號（54.5±2.1%）﹥寶島蕉（50.9±3.1%）。總和所有試驗結果發現香蕉果皮具優異的抗氧化能力，因此其萃取物再進一步評估抑制脂質過氧化的效能，結果顯示此實驗具有濃度依賴性，並且以乙醇萃取物的效果優於水萃物。在總酚含量的測定上，研究結果顯示李林蕉果肉粗多醣擁有最豐富的含量（114.5 ± 1.1 mg GAE/g），並且
發現其含量與清除DPPH•和ABTS•+自由基試驗結果呈正相關性。
雖然實驗結果顯示李林蕉具有最佳的抗氧化能力，但由於有產量小及產季短的缺點，因此本研究選擇產量大且抗氧化活性也表現優異的台蕉五號進行進一步的活性成分追蹤。在台蕉五號活性成分分離純化之結果顯示，果皮含有兒茶素（catechin）及沒食子兒茶素（gallocatechin）等具有優異抗氧化效能的天然成分。
本研究結果也顯示出香蕉之抗氧化作用集中在中高極性層，與活性追蹤所獲得的抗氧化成分為接近的極性範圍，因此利用簡單的層析即可獲得較優異效能的萃取液，去蕪存菁排除不具功效的雜質，如此提高效能的萃取液添加於化粧保養品中，確保所製造保養品之功效，強化產品機能性、技術性與市場特殊性。
In this research, we choose three strains of ripe banana in Taiwan (Musa pisang lilin, Musa formosana, Musa tai chiao No.5) to get the extracts, so as to test their moisturizing and antioxidant capacity. And, to go a step further, we select a strain Musa tai chiao No.5 to study the active ingredient in depth as it’s extensively cultivated and it has a great amount of yield. We hope this research can help us to clarify the skin refining ability of those extracts from three strains mentioned above. By taking the result into consideration, we can estimate whether these extracts have the potential to become raw materials in cosmeceutical products or not.
We use two solvents ( 95% ethanol and deionized distilled water) to get water and ethanol extracts of banana peel and pulp respectively. On the other hand, a part of water extracts is taken to be added to five times the volume of 95% ethanol with a view to obtain crude polysaccharide extractions. All extracts here are taken into many tests including moisture absorption, moisture retention, free radical DPPH• scavenging, free radical ABTS•+ scavenging, ferrous iron chelating and lipid peroxidation inhibition.
The result of moisturizing test show that the crude polysaccharide extractions from peel and pulp of all the three strains have the same or similar moisture absorption and moisture retention ability compared with the standard, hyaluronic acid. And the amount of crude polysaccharide in every part of three strains is similar to one another, excluding crude polysaccharide from the pule M. formosana. Its quantity of crude polysaccharide is a bit higher than others.
In the antioxidant activity test, result shows that all the water extracts form banana have better DPPH• scavenging ability which is superior to the 95% ethanol extracts. Furthermore, water extracts from peel have the best effect. In a concentration 1000 g/mL, all of water extract from peel have scavenging rate that are higher than 90%. The scavenging ability from high to low are M. tai chiao No.5（93.8±0.4%）, M. formosana（91.8±0.9%）, M. pisang lilin （91.3±0.7%）；All of the extracts from peel in 95% ethanol have a scavenging rate that are higher than 80%. Ability arrangements from high to low are M. formosana（91.6±0.4%）, M.tai chiao No.5（80.8±0.9%）, M. pisang lilin （80.1±0.7%）; On the other hand, the water extract from pulp（88.9±0.5%）and crude polysaccharide extract（51.7±1.0%）in M. pisang lilin have a relatively higher DPPH• scavenging activity compared to other pulp and crude polysaccharide extracts.
The ABTS• + scavenging abilities of all the extracts at a concentration 100 g/mL from high to low are crude polysaccharide extracts > peel extracts > pulp extracts. In addition, water extracts are superior to ethanol extracts ; crude polysaccharide in pulp is superior to that in peel. The scavenging ability from high to low are pulp crude polysaccharide from M. pisang lilin（99.0±0.5%） > peel water extract from M. tai chiao No.5（90.4±0.5%）> peel water extract from M. formosana（89.3±0.8%）> pulp water extract from M. pisang lilin （71.3±0.3%）> pulp crude polysaccharide from M. formosana（66.7±0.1%）> pulp crude polysaccharide from M.tai chiao No.5（62.8±1.1%）> peel crude polysaccharide from M. formosana（54.7±0.2%）.
At a concentration 2000 g/mL, the ferrous iron chelating ability from high to low are the crude polysaccharides in peels > the crude polysaccharides in pulps > the ethanol extracts from peels. Chelating ability among three strains in peel crude polysaccharides from high to low are M. pisang lilin（95.7±0.1%）> M. formosana（93.6±0.5%）> M. tai chiao No.5（75.2±1.0%）. M. tai chiao No.5 （79.0±2.0%）is superior to M. pisang lilin（59.1±0.8%）and M. formosana （58.3±2.0%）at their pulp crude polysaccharides in ferrous iron chelating test; And the peel ethanol extract of M. pisang lilin（57.3±0.7%）is better than those of M. tai chiao No.5（54.5±2.1%） and M. formosana （50.9±3.1%）.
To sum up the result above, we find that there is a good antioxidant activity in banana peels. So, we take their peel extracts to assess the lipid peroxidation inhibition. Result show that the inhibition rate is concentration dependence, and the effects of ethanol extracts are superior to water extracts.
Besides, we find the polyphenol content in pulp crude polysaccharides of M. pisang lilin（114.5±1.1 mg GAE/g）is much more abundant than others. The polyphenol quantity is positive correlation to free radical DPPH• and ABTS•+ scavenging activity.
Although in the end we find that M. pisang lilin extracts have the best antioxidant activity. But its small quantity of yield and short gathering season reduce its potential application. At last, we choose the strain M. tai chiao No.5 which also has great antioxidant activity to trace the activity compounds in it. After separating and purifying the activity compounds in it, we find that there are catechin and gallocatechin, which have the great antioxidant activity, in the peel of the fruit.
In this research, we also find that antioxidant ingredients appear at medium to high polar regions in the column. It is closely to the result of activity compounds which we find out. In conclusion, by using simple chromatograph technique, we can obtain great performance extracts. By adding these extracts to cosmeceutical products, we can rise its functionality, technicality, keeping it outstanding and ensuring its efficiency. |
