以冷電漿處理鳳梨皮廢棄物生產細菌纖維素

Abstract

本研究利用農業廢棄物鳳梨皮透過化學酸解法降解為醱酵碳源，並利用常壓非熱電漿(atmospheric cold plasma, ACP)來分解於酸解過程中產生之醱酵抑制物質如糠醛、羥甲基糠醛與甲酸，並將其應用於細菌纖維素(bacterial cellulose, BC)生產。由實驗結果可發現每克乾燥鳳梨皮於酸解後可獲得0.65 g可發酵糖，並產生0.012 g甲酸、0.0032 g糠醛與0.045 g 羥甲基糠醛。透過比較不同氣體ACP與功率後，可發現於空氣電漿(功率600 W)或氬氣電漿(功率200 W)處理30分鐘後，糠醛、羥甲基糠醛與甲酸可被降解至其對於BC產量的最小抑制濃度(分別為0.0125%、0.00625%與0.025%)。後將電漿解毒之鳳梨皮酸解液應用於BC生產，可發現與未解毒酸解液相比，其BC產量可由1.28 g/L提高到3.81 g/L。於BC材料特性分析結果可發現，ACP解毒鳳梨皮水解液組別之BC於材料特性上皆與一般培養液組別相同，像是於掃描式電子顯微鏡結果可發現其具備奈米網狀纖維結構，於X光繞射結果亦發現於結晶型上無差異(cellulose Iα)，且於保水性上，ACP解毒鳳梨皮組別之BC亦具備高保水性(98.7%)。綜論以上，本研究透過優化ACP解毒效率，藉此降低鳳梨皮酸解過程所產生之發酵抑制物濃度，並將此解毒酸解液用於細菌纖維素生產，發現可有效提升其產量，因此除了有利降低其生產成本外，更可作為農業廢棄物再利用之用途，未來擬透過放大處理製程與解毒，以建立適合用於工業生產BC之綠色發酵製程。

This study aimed to release the carbon source from pineapple peel waste (PPW) by acid hydrolysis, followed by utilizing the atmospheric cold plasma (ACP) to decompose fermentation inhibitors for bacterial cellulose (BC) production. 0.65 g of fermentable sugar was obtained from per gram of dried pineapple peel, along with inhibitors, 0.012 g, 0.0032 g, and 0.0045 g of formic acid, furfural, and hydroxymethylfurfural (HMF), respectively. With optimized ACP parameters, 600 W of power with working gas of air, or power of 200W with working argon gas for 30 min, a significant reduction of inhibitors was achieved (close to the minimum inhibitory concentration for BC production). The detoxified PPW hydrolysates showed higher BC yield (3.81 g/L) compared to the conventional medium. BC from the ACP detoxification PPW hydrolysate exhibited the typical characteristics including cellulose Iα, high water content (98.79%), and ultra-fine nanofiber structure. In summary, ACP to fermentation could effectively detoxify inhibitors within PPW hydrolysate, thereby enhance BC yields with low production cost and reuse of agricultural waste. It is possible to establish a green fermentation process for the industrial scale production of BC through the use of the scale-up process and detoxification via ACP.