食源性生物材料源于常见食物，它们是众多微米级或纳米级尺寸单元自组装的集合体，富含多种营养成分和活性物质。本文从常见食物材料入手，以简单可行的方法将其制备成能够应用于组织工程或纳米递药领域的产品。这无疑将为探索和开发新型生物材料提供更为开阔的思路。 本文首先从豆腐入手，豆腐源于大豆，富含大豆蛋白、大豆异黄酮等多种活性组分，属于天然蛋白凝胶，观其形态其己初步具备组织工程支架的雏形。本文在传统豆腐制备工艺的基础上进一步将其开发成豆腐组织工程支架(以下简称豆腐支架)并探索了豆腐支架在生物医学应用中的可行性。扫描电镜结果可知豆腐支架内部具有不规则多孔结构，利于细胞粘附和生长。体外生物相容性实验结果表明，相比于化学交联的大豆分离蛋白支架，豆腐支架表现出更小的细胞毒性。动物实验结果表明豆腐支架具有良好的生物相容性，且从材料植入后的切片分析结果来看豆腐支架组有大量微血管生成迹象，这将有利于局部组织营养物质的供应和流通，可推测其在皮肤创伤修复应用中具有一定潜在价值。 在豆腐支架前期探索性工作的基础上，本文进一步将豆腐支架在创伤修复应用中的可行性进行深入挖掘。根据豆腐支架的特性，本文将其与甲基丙烯酸酯化明胶(GelMA)复合，成功开发了甲基丙烯酸酯化明胶/豆腐复合水凝胶(GelMA/tofu hybrid hydrogels)并将其作为创伤敷料进行应用。理化性能表征显示，随着豆腐支架比例的增加，复合水凝胶的孔径逐渐增大，压缩模量逐渐降低。体外抗氧化性能表征显示豆腐支架的引入使复合水凝胶具有良好的DPPH和羟基自由基清除活性。与巨噬细胞(RAW264.7)共孵育，发现复合水凝胶有刺激RAW264.7向M2型巨噬细胞分化的作用，其在创伤修复后期能分泌大量细胞生长因子，促进细胞分化和增殖。动物实验结果表明GelMA/tofu水凝胶能够加速创口愈合。以上结果表明，本研究成功构建了具有抗氧化活性和免疫刺激性的GelMA/tofu复合水凝胶并在大鼠皮肤创伤修复应用中取得良好的治疗效果。 豆腐支架的抗氧化活性有助于改善创伤修复效果，预示其它具有良好抗氧化活性的食源性材料在创伤修复产品开发中的潜在价值。为此，我们进一步选择富含抗氧化活性组分的红枣用来开发具有促修复功能的创伤敷料产品。本研究在尽量保持红枣组分完整性的前提下使用简单可行的方法开发了甲基丙烯酸酯化明胶/红枣复合水凝胶(GelMA/RJ hybrid hydrogels)并对比了不同比例红枣组分的复合水凝胶对于治疗皮肤缺损的效果。结果表明，红枣的引入使复合水凝胶体系具有抗氧化活性，可有效防止氧化应激损伤。巨噬细胞RAW264.7经GelMA/RJ复合水凝胶处理后，出现向M2表型分化迹象，说明GelMA/RJ复合水凝胶对其有轻微程度的刺激作用。改善的皮肤创口愈合效果进一步表明GelMA/RJ复合水凝胶是具有良好应用前景的促创伤修复敷料。本研究工作将为其它食源性生物材料在创伤修复应用研究中提供借鉴思路。 前部分的工作主要是围绕食源性生物材料在组织工程应用领域的可行性展开，下一部分工作我们将探索其在纳米递药领域的应用前景。本着食源性生物材料可食用性的特点，在这部分研究工作中，我们进一步探索食源性生物材料在递送口服药物应用中的可行性。众所周知蛋清中富含蛋白质，其氨基酸组成最接近人体营养需求，利用率达90%以上，而蛋白作为纳米药物载体具有良好的生物相容性，在此我们选择蛋清作为研究主体，利用一种绿色安全且易于实现的仿蛋花汤制备过程的工艺开发了基于蛋清蛋白的纳米载药体系用于负载紫杉醇(PTX/EW-NPs)并考察了其对CT26.WT肿瘤的抑制作用。实验结果表明，优化后的EW-NPs及PTX/EW-NPs纳米递药体系具有小于100nm粒径尺寸，紫杉醇的载药量为7.2±0.54%。体外细胞实验表明PTX/EW-NPs能显著抑制CT26.WT细胞的迁移和侵袭。动物实验表明，PTX/EW-NPs可以改善口服给药后肠段对PTX的摄取，更重要的是，在保证生物安全性的前提下，可以发挥灌胃给药和静脉注射给药两种给药方式的协同作用，并实现PTX/EW-NPs向肿瘤组织的被动靶向从而增强PTX抗肿瘤功效。本研究工作将为其它基于食源性生物材料的新型纳米递药体系的开发与应用提供借鉴思路。 本文首次将食源性生物材料的理念引入到生物材料研究中，并根据不同食源性生物材料自身特点构建不同功能体系。本论文的主体研究内容是对食源性生物材料在组织工程和纳米递药体系研究中一个探索性工作，将为后期食源性生物材料的系统研究指引方向，也为其它食源性生物材料的深入开发提供借鉴思路，是极具创新性的研究工作。 关键词：食源性生物材料；豆腐支架；复合创伤敷料；蛋清纳米载体

 Food-based biomaterials derived from common diets, are the self-assembled collections of large number of micro- or nano-scale units with abundant nutrients and active substances. In this work, a simple and feasible method was selected to make these biomaterials successfully applied in tissue engineering or nano-drug delivery systems, which will provide a broader perspective for the research on other novel biomaterials. Tofu as a common food originating from soybean are rich in soy protein, soy isoflavones and other bioactive substances. In terms of the morphology, tofu, a natural protein gel, has already possessed the prototype of tissue engineering scaffold. Therefore, in this part, tofu was furtherly developed into tofu scaffold based on the traditional manufacturing process, and the possibility of tofu to apply in tissue engineering was evaluated with chemically cross-linking based soybean protein scaffold set as the control. The SEM results showed that the tofu scaffold had an irregular porous structure, which was conducive to cell adhesion and growth. In vitro experiments results indicated that the tofu scaffold showed less cytotoxicity than the chemically cross-linked soy protein scaffold. The subcutaneous implantation results showed that tofu scaffold could be well tolerated by Sprague-Dawley rats (SD rats). The pathological sections showed a lot of microvascular formation signs in tofu scaffold groups, which would be beneficial to the nutrient supply and circulation, suggesting the feasibility to apply tofu scaffold in wound healing. Based on the preliminary exploration of tofu, in this part of work, tofu scaffolds were applied in wound repairing. Herein, gelatin-methacryloyl/tofu (GelMA/tofu) hybrid hydrogels were prepared successfully by combining GelMA and tofu scaffold, and worked as wound dressing. The physicochemical characterization showed that the pore size gradually increased and the compressive modulus gradually decreased when enhancing the tofu proportion in hybrid hydrogels. The results of in vitro antioxidant performance showed that the introduction of the tofu scaffold gave the hybrid hydrogel a good DPPH and hydroxyl radical scavenging activity. Cell experiments indicated that the hybrid hydrogels were beneficial for RAW264.7 to differentiate into M2 phenotype. Animal experiments showed that GelMA/tofu hydrogel can accelerate wound healing. The results above indicated that GelMA/tofu hybrid hydrogels had been successfully constructed and an improved wound healing effect had been achieved by the help of GelMA/tofu hybrid hydrogels. It can be learned that the antioxidant activity of materials will be helpful to accelerate wound healing, suggesting food-based biomaterials rich in antioxidant components will be good candidates for the development of wound dressing. In this part, red jujube, which is rich in antioxidant ingredients, was developed into gelatin-methacryloyl/red jujube (GelMA/RJ) hybrid hydrogels by a simple and feasible method when maintaining the integrity of the jujube components. The results showed that the introduction of red jujube equipped GelMA hydrogels with antioxidant activity, which could effectively prevent oxidative stress damages. A slight immunostimulatory effect was observed by the morphology of macrophages after treated with hybrid hydrogels. The improved wound healing effect further indicated that the GelMA/RJ hydrogel was a promising wound healing material. Tofu and red jujube had successfully achieved good therapeutic effect working as wound dressing. Furthermore, the possibility of food-based biomaterials to improve therapeutic effect of oral drug delivery has been explored in the last part of this work. As known, the composition of amino acids in eggs most matched the nutrition people daily demand, and the utilization rate of eggs is over 90%. In this part of work an egg white based nano-drug delivery system (EW-NPs) was developed by a green, biosafe and easy to realize preparation method, which simulated the process of egg soup preparation. The results indicated that the particle size of EW-NPs or PTX/EW-NPs was no more than 100 nm, the PTX loading efficiency was about 7.2±0.54%. In vivo studies indicated that PTX/EW-NPs could enhance the absorption of PTX in intestine, and more importantly, the synergistic antitumor effect was achieved by combining intragastric administration (ig) and intravenous administration (iv). The targeting tumor effect by PTX/EW-NPs furtherly enhanced the concentration of PTX in tumor and improved the antitumor effect. This research work will provide a reference for the development of other novel nano-drug delivery systems. By our work, the “food-based biomaterials” concept was first introduced in the field of biomaterials research, and different functional systems were constructed according to the characteristics of biomaterials. The research in this thesis is an exploratory work to apply food-based biomaterials in tissue engineering or nano-drug delivery systems, which is a very innovative research work, providing new ideas for the deep research of other food-based biomaterials. Key words: Food-based biomaterials; Tofu scaffolds; Hybrid wound dressings; Egg white-based nanocarriers