角黃素異位修飾泡沫狀細菌性纖維素用於食品活性包裝之開發

Abstract

食品保存與安全已成為全球重視的議題，然而傳統食品包裝多僅具備被動隔離功能，對於延長食品保存期限與抑制品質劣變效果有限。為此，本研究旨在開發一種具抗氧化功能的活性包裝材料，結合泡沫狀細菌性纖維素 (foaming bacterial cellulose, FBC) 與天然類胡蘿蔔素角黃素 (canthaxanthin, CX)，以提升 其保鮮與應用潛力。FBC 係利用含 cremodan 與 xanthan 的泡沫培養基培養Komagataeibacter sucrofermentans 所得，CX 萃取液則透過 Escherichia. coli/pAC-CANTHipi 培養液中進行萃取，並依據培養液體積與萃取溶液體積比 (1 : 1、3 : 1、5 : 1、7 : 1、10 : 1) 區分為不同濃度組別 (CX1、CX3、CX5、CX7與CX10)，進行萃取後用於 FBC 之異位修飾並製得 FBC/CX 膜材。研究結果顯示，FBC 成功製備並順利以 CX 進行異位修飾，修飾後之 FBC/CX 膜呈現濃度依賴性之橘紅色外觀，抗氧化分析亦證實 CX1 至 CX7 萃取液具有良好線性增長之抗氧化能力，並於 FBC/CX10 測得樣品之 Trolox 當量為4.86 ± 0.73 mg/g，自由基清除率達 21.30 ± 1.43 %，遠高於未修飾 FBC (1.10 ± 0.202 mg/g 與 3.30 ± 0.74 %)。細胞實驗結果亦證實所有膜材對 NIH-3T3 小鼠胚胎成纖維細胞皆具良好生物相容性。進一步應用於鱸魚冷藏包裝試驗中， FBC/CX10 展現優異的抑菌與抗氧化效果，在總生菌數分析結果中，FBC/CX10 於第 3 天相較 Blank 組抑菌率達 73.95 %，第 9 與第 12 天則分別達到 76.52 % 與 77.62 %。在脂質氧化指標方面，儲存第 3 天硫代巴比妥酸反應物質變化結果顯示 FBC/CX10 樣品之丙二醛濃度為 0.68 ± 0.05 mg/g，顯著低於未包裝 Blank 組 (1.25 ± 0.49 mg/g) 與 FBC 組 (1.52 ± 0.16 mg/g) ，顯示 FBC/CX10 薄膜於冷藏初期能有效抑制脂質氧化，透過此試驗可知該薄膜可有效抑制前 3 天之總生菌數到達腐敗標準及延緩硫代巴比妥酸反應物質變化指標上升，證實其於活性食品包裝應用具高度潛力。

Food preservation and safety have become globally important issues. However, conventional food packaging typically offers only passive barrier functions and provides limited effectiveness in extending shelf life or preventing quality deterioration. To address this limitation, this study aimed to develop an active packaging material with antioxidant properties by integrating foaming bacterial cellulose (FBC) and a natural carotenoid, canthaxanthin (CX), to enhance preservation performance and application potential. FBC was produced by cultivating Komagataeibacter sucrofermentans in a foamed medium containing cremodan and xanthan, while CX extract was obtained from the culture medium of Escherichia coli/pAC-CANTHipi. The extracts were classified into five concentrations (CX1, CX3, CX5, CX7, and CX10) based on different volume ratios between culture broth and extraction solvent (1:1, 3:1, 5:1, 7:1, 10:1), and then used for ex situ modification of FBC to obtain FBC/CX composite films. The results demonstrated the successful preparation of FBC and its subsequent modification with CX. The modified FBC/CX films exhibited a concentration-dependent orange-red appearance. Antioxidant analysis confirmed that CX extracts from CX1 to CX7 displayed a good linear increase in antioxidant activity. Specifically, the FBC/CX10 film exhibited a Trolox equivalent of 4.86 ± 0.73 mg/g and a free radical scavenging rate of 21.30 ± 1.43 %, significantly higher than the unmodified FBC (1.10 ± 0.202 mg/g and 3.30 ± 0.74 %). Furthermore, cytocompatibility assays confirmed that all films exhibited good biocompatibility with NIH-3T3 cells. In the refrigerated packaging test using fish fillets, the FBC/CX10 film showed excellent antimicrobial and antioxidant effects. Total viable count analysis revealed that FBC/CX10 reduced microbial growth by 73.95 % on day 3 compared to the blank group, and by 76.52 % and 77.62 % on days 9 and 12, respectively. Regarding lipid oxidation, the malondialdehyde (MDA) content in FBC/CX10 on day 3 was 0.68 ± 0.05 mg/g, significantly lower than that of the blank (1.25 ± 0.49 mg/g) and FBC (1.52 ± 0.16 mg/g) groups, indicating that FBC/CX10 films effectively suppressed lipid oxidation in the early stages of cold storage. These findings confirm that FBC/CX10 films have high potential as active materials for food packaging applications, capable of delaying microbial spoilage and oxidative degradation.