Lee Jeongho, Kim Seunghee, Kwon Hyeok Ki, Song Yunseok, Shin Soeun, Kim Minji, Son Hyerim, Park Chulhwan, Yoo Hah Young
Department of Biotechnology, Sangmyung University, Seoul 03016, Republic of Korea.
Department of Chemical Engineering, Kwangwoon University, Seoul 01897, Republic of Korea.
Int J Biol Macromol. 2025 Apr;299:140044. doi: 10.1016/j.ijbiomac.2025.140044. Epub 2025 Jan 18.
Dieckol is a brown algal phlorotannin with potent bioactivities such as hepatoprotective effects. This study aimed to produce dieckol-rich extract from Eisenia bicyclis and apply them as a functional ingredient for a novel bacterial cellulose (BC)-based dessert. The modeling and optimization of the ultrasound-assisted extraction (UAE) process were performed. The developed model showed that at least one of the linear or quadratic terms of all variables (amplitude, solvent concentration, temperature, and time) affected dieckol recovery (p < 0.05). Following numerical optimization, dieckol recovery achieved 17.3 mg/g biomass under optimal conditions (62 % amplitude, 35 % solvent concentration, 70 °C, and 6 min), similar to the model-predicted value (18.3 mg/g). Then, BC-dieckol (BC-D) pellicles were fabricated by ex situ loading 25, 50, 75, and 100 % of the liquid extract with 9.954 mg dieckol (recommended intake level). All BC-D pellicles showed high dieckol loading (98.16 - 100 %), and BC-D100 meets the acceptable level. The FTIR and SEM analyses confirmed the impregnation of the extract, especially the signature peaks of dieckol, related to aromatic ether stretch and aromatic ring structure of phlorotannin by the FTIR spectra. The crystallinity index and water absorption capacity of BC-D100 were determined to be about 83.9 % and 415.6 %, respectively, which were slightly decreased compared to BC-control, but not significantly. In addition, BC-D100 has shown antioxidant activity making it valuable as a food material. This study provides valuable information for the food industry, paving the way for developing novel BC-based foods using brown algal extracts.
二eckol是一种具有强大生物活性（如保肝作用）的褐藻多酚。本研究旨在从昆布中制备富含二eckol的提取物，并将其作为一种功能性成分应用于新型细菌纤维素（BC）基甜点中。对超声辅助提取（UAE）过程进行了建模和优化。所建立的模型表明，所有变量（振幅、溶剂浓度、温度和时间）的线性或二次项中至少有一项会影响二eckol的回收率（p < 0.05）。经过数值优化，在最佳条件（62%振幅、35%溶剂浓度、70°C和6分钟）下，二eckol的回收率达到17.3毫克/克生物量，与模型预测值（18.3毫克/克）相似。然后，通过异位加载含有9.954毫克二eckol（推荐摄入量）的25%、50%、75%和100%的液体提取物来制备BC-二eckol（BC-D）薄膜。所有BC-D薄膜都显示出高的二eckol负载量（98.16 - 100%），并且BC-D100达到了可接受水平。傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）分析证实了提取物的浸渍，特别是FTIR光谱中与多酚的芳香醚伸缩和芳香环结构相关的二eckol的特征峰。BC-D100的结晶度指数和吸水能力分别测定为约83.9%和415.6%，与BC对照相比略有下降，但不显著。此外，BC-D100已显示出抗氧化活性，使其作为食品材料具有价值。本研究为食品工业提供了有价值的信息，为利用褐藻提取物开发新型基于BC的食品铺平了道路。
