丝胶对壳聚糖膜在模拟体液内降解的调控作用

壳聚糖具有优良的生物活性、生物相容、生物降解和抗菌功能；丝胶/壳聚糖复合物具有良好的人体亲和性，本研究将丝胶与壳聚糖乙酸胶液匀和．检测了其粘流特性．将二元共混膜被置于模拟体液内，扫描电镜的形态结构观察表明丝胶均匀分散于壳聚糖中。可调控膜的降解，复合物为生物材料和功能性纤雄的制备提供了新素材。     

壳聚糖与聚乙烯醇共混成纤的可行性研究

壳聚糖是天然氨基多糖甲壳素脱去乙酰基的派生物，具有良好的生物相容性和广谱抑菌功效。文章根据壳聚糖的溶解性质，探讨了不同条件下壳聚糖乙酸胶液的粘度变化规律，并使用一定浓度的聚乙烯醇胶液共混共溶，最终筛选出壳聚糖与聚乙烯醇的共混成纤的条件，为工业化制备壳聚糖／聚乙烯醇复合纤维提供可参考的工艺技术路线。     

棉织物的丝胶涂层整理及其性能

为开发高品质、功能性的棉制品,采用带负电荷的丝胶蛋白与带正电荷的壳聚糖衍生物在水溶液中发生反应,生成具有一定胶黏作用的新型微颗粒,再通过聚丙烯酸类低温交链剂进一步将丝胶固着在棉织物上。对整理前后棉织物的服用性能、表面形态等进行测试,结果表明:丝胶均匀涂覆在棉织物上,且耐洗性良好,洗涤5次后的溶失率约为0.21%,丝胶整理后棉织物的吸放湿性、保温性、透湿性和抗菌性均有提高,透气性基本不变,是一种新型高档棉制品。     

壳聚糖绒成型工艺的设计与应用

采用壳聚糖乙酸胶液置于贮浆罐内高速离心喷甩与旋转磁场及磁性转子形成凝固浴旋转涡流的方法，将喷甩出的壳聚糖胶液丝流与同向转动的涡流内壁接触而被拉伸并定型。在旋转浴液与丝流同向拉伸的同时，丝流更加纤细化，且调整成型工艺可获得期望的绒长和纤度。该研究为生物医学以壳聚糖作裁体的丝网型药物控制释放系统和抗茵功能性纺织品的制备，提供了可批量生产的理想素材。     

氧化壳聚糖/丝胶复合物的制备及其对棉织物的功能整理

为开发高品质的棉制品,采用氧化壳聚糖与丝胶蛋白共价结合制备氧化壳聚糖/丝胶蛋白复合物,将其应用于棉织物的功能改性整理。研究了各因素对棉织物质量增加率的影响,得出最优工艺参数。利用红外光谱仪、扫描电子显微镜等测试手段对复合物及其整理后的棉织物进行分析与表征。结果表明:壳聚糖经高碘酸钠氧化后引入活性基团醛基,与丝胶产生席夫碱反应制成复合物整理剂,将复合物应用于棉织物的整理,可与纤维产生化学键合,并在其表面交联成膜;随着壳聚糖氧化度的增加,复合物中丝胶溶失率明显减少;复合物改性棉织物的强力和吸湿性变化不大,而折皱回复性、防紫外线性和抑菌性均明显提高;3次水洗后,棉织物的质量增加率稳定在4%左右,其耐洗性能良好。     

壳聚糖与表面活性剂复合物的抑菌活性及抑菌机理研究

本文对壳聚糖与表面活性剂十二烷基磺酸钠（SDS）、十六烷基三甲溴化铵（CTAB）、曲拉通（TritonX-100）的复合物对大肠杆菌和金黄色葡萄球菌的抑菌活性进行了研究。结果表明：壳聚糖与CTAB、TritonX-100复合物对大肠杆菌抑菌活性强干壳聚糖,合成的三种复合物对金黄色葡萄球菌抑菌活性强于壳聚糖。其中壳聚糖-CTAB复合物抑菌活性最强,且织物经该复合物的整理后,也具有了较强的抗菌作用,故选择壳聚糖-CTAB的复合物考察抑菌机理。通过测定壳聚糖-CTAB作用后菌液中O．D260nm和0．D280nm、细胞膜蛋白荧光强度的变化,分别研究细菌细胞膜的完整性和细胞膜蛋白结构的变化。结果发现,壳聚糖-CTAB影响了细胞膜蛋白结构,使细胞膜破坏,从而达到抑菌作用。     

戊二醛改性壳聚糖复合物的制备与抗菌活性

以戊二醛为交联剂,壳聚糖与它以不同比例进行交联,其产物呈树脂状,对5组交联壳聚糖进行抗菌试验,研究了该复合物对大肠杆菌,枯草芽孢杆菌和金黄色葡萄球菌的抗菌活性。结果表明:该复合物对金黄色葡萄球菌具有较好的抗菌作用,壳聚糖与戊二醛的用量比为4 g/mL时抗菌效果最佳。     

TG酶催化丝胶和壳聚糖对羊毛织物的抗菌整理

为了提高羊毛织物的抗菌性能,以处理后羊毛织物的增重率为考核指标,采用谷氨酰胺转胺酶(TG酶)催化丝胶、壳聚糖和羊毛的接枝反应,对羊毛织物进行整理。利用X-射线光电子能谱、扫描电子显微镜(SEM)和热重分析对比织物整理前后的变化,结果表明丝胶和壳聚糖与羊毛发生接枝反应。整理后羊毛织物对金黄色葡萄球菌和大肠杆菌的抑菌率都大于99%,断裂强力提高,白度有所下降。经20次水洗后,对金黄色葡萄球菌和大肠杆菌抑菌率分别为86.8%和83.9%,说明具有很好的抗菌性能。     

丝胶-壳聚糖对兔毛的改性处理

采用壳聚糖作为固着剂,在微波场中运用丝胶对兔毛纤维进行改性处理。考虑丝胶质量分数、壳聚糖质量分数、微波处理液pH值、微波参数和水洗温度5个因素,对实验方案进行优化设计,并讨论了各因素对兔毛纤维改性处理效果的影响。根据改性处理综合效果确定最优方案为:丝胶质量分数2%,壳聚糖质量分数1.2%,微波处理液pH值4.5,微波参数为:P30火力加热7 min,停2 min,再加热7 min,水洗温度为常温。     

丝胶复合纳米口罩的制备及其抗菌性性能研究

以丝胶蛋白、聚环氧乙烷为原料,将20%SS水溶液与6%PEO水溶液配制SS/PEO纺丝液,采用静电纺丝技术,以无纺布为基底接收静电纺纳米纤维制备丝胶复合纳米口罩用料。探讨丝胶复合纳米口罩的抗菌性。结果表明:通过抑菌圈法观测丝胶纳米复合口罩样品周围有明显的抑菌圈;通过振荡法定量分析,丝胶纳米复合口罩对金黄色葡萄球菌、大肠杆菌的抑菌率分别达到45.17%和48.5%;说明丝胶纳米复合口罩具有较好的的抗菌性能。     

壳聚糖的抗菌性研究进展与抗菌纺织品开发

为深入研究壳聚糖（CS）在抗菌纺织品上的应用,对CS的抗菌机制及其抗菌纺织品开发现状进行综述。介绍了分子量、脱乙酰度、溶液浓度、pH值、溶剂种类、衍生化等因素与抗菌性的关系。结合实际应用认为,CS要发挥优良的抗菌性,应具有高脱乙酰度、中等分子质量,以乙酸作为溶剂,pH值略高于4即可,同时其质量浓度在2.5g/L以上,还可通过衍生化反应进一步提高其抗菌性。分析CS抗菌纺织品开发现状得知,目前主要通过对传统织物固着CS后整理和开发CS纤维制品这2种方式实现纺织品抗菌,前者抗菌性会随产品洗涤次数增加而逐渐降低,而后者将是较好的解决办法,但还有待进一步研究。     

氦气等离子体改性技术对壳聚糖材料结构与抗菌性能的影响

考虑到微生物污染引起的相关安全性问题,为了改善壳聚糖材料的抗菌性能,提高壳聚糖基抗菌材料的进一步应用,本文利用等离子体技术,在氦气氛围下对壳聚糖材料进行改性处理,设计得到改性壳聚糖抗菌材料,并通过抗菌实验、游离蛋白/核酸等的测定,探讨改性壳聚糖材料的抗菌性能与作用机制。通过改性壳聚糖结构分析,壳聚糖材料经氦气等离子体改性后,光斑区和非光斑区表面均变得粗糙,但光斑区的粗糙程度更加明显,材料表面的-NH₂比例下降（83.32%下降到72.10%）,而-CONH₂的比例上升（16.68%上升到27.90%）,这与改性过程中带电粒子的碰撞及壳聚糖材料中化学键的断裂有关。抗菌实验结果表明,相比于未改性材料,等离子体改性壳聚糖材料显著提高大肠杆菌的抗菌性能（P<0.05）,而对于金黄色葡萄球菌,改性前后并没有显著性差异（P>0.05）。改性壳聚糖材料表面的化学基团变化,其与细菌接触时,能明显改变细菌细胞膜通透性,并局部形成不利于细菌生长的环境,从而达到抗菌的效果。     

壳聚糖基纳米纤维载药体系及其缓释行为

为研制具有缓释效果的抗菌材料,以壳聚糖(CS)、聚乙烯醇(PVA)为原料,采用静电纺丝技术制备CS/PVA 复合纳米纤维膜并负载环丙沙星;探究纺丝体系、纺丝工艺对纤维膜微观形貌、接触角、化学结构的影响,分析药物体外释放行为及载药前后试样的抗菌性。结果表明：PVA 的加入提高了CS 的可纺性;改善了纤维膜的亲水性;当纺丝电压为24 kV、CS 和PVA 质量比为1：1. 5 时,纤维膜成网均匀,形貌良好;载药纳米纤维膜具有相对较低的药物释放速率,可有效避免药物突释,且药物释放速率随纤维膜中环丙沙星质量分数的增大而增大;载药CS/PVA 纳米纤维膜对金黄色葡萄球菌具有优良的抗菌性。     

水杨酸/季鏻盐双改性壳聚糖抗菌保鲜剂的制备及表征

该研究以天然高分子壳聚糖（CS）为基体,首先分别用水杨酸（SA）和季鏻盐（TPPB）接枝改性壳聚糖,通过单因素实验确定壳聚糖和水杨酸、季鏻盐的最佳摩尔比,得到SA-CS和TPPB-CS聚合物,再以水杨酸壳聚糖衍生物为底物,加入不同摩尔比的季鏻盐,通过水溶性分析选出最佳摩尔比,得到SA-CS-TPPB聚合物;并通过红外光谱、核磁共振、X射线衍射和热重分析等对所得到的三个聚合物进行结构性能表征,最后通过抑菌圈实验分析SA-CS、TPPB-SA和SA-CS-TPPB聚合物的抗菌性能。结果表明,最优反应摩尔比CS:TPPB:SA为1:1:0.75;所得壳聚糖衍生物有很好的溶解性和抗菌性,溶解性可达100.00%,对金黄色葡萄球菌和大肠杆菌有很好的抑制效果,且对金黄色葡萄球菌的抑制效果优于大肠杆菌。SA对提高CS抗菌性要比TPPB效果好,季鏻盐对提高壳聚糖水溶性比水杨酸好,采用水杨酸和季鏻盐共同改性壳聚糖对提高其水溶性和抗菌性有协同增效作用,所得壳聚糖衍生物比壳聚糖有更好的成膜性能,为壳聚糖改性在果蔬涂膜保鲜中的应用提供理论依据。     

Cross-linking activity of oxidised tannic acid towards mackerel muscle proteins as affected by protein types and setting temperatures

Cross-linking activity of oxidised tannic acid (OTA) at different levels (0–0.3% of protein content) towards natural actomyosin (NAM), sarcoplasmic protein (SP) and NAM/SP (65:35) mixture from mackerel (Rastrelliger kanagurta) muscle incubated at different temperatures for 30 min was investigated. NAM solution showed an increase in turbidity, surface hydrophobicity and disulphide bond contents as OTA added increased up to 0.2%. The higher aggregate formation of NAM solution containing 0.2% OTA was found when incubated at 40 °C, compared with at room temperature (26–28 °C). The lower aggregation of NAM was noticeable in the presence of SP, which was more preferably cross-linked by OTA via weak bonds. Thus, SP showed the interfering effect on NAM cross-linking induced by OTA. Myosin heavy chain (MHC) band intensity was decreased and a highly ordered dense protein network of NAM was obtained when 0.2% OTA was incorporated. Conversely, coagulation was formed in the NAM/SP mixture added with 0.2% OTA. Thus, the cross-linking efficiency of OTA varied with the type of muscle protein and setting temperature.     

Processing whole cottonseed moderates fatty acid metabolism and improves performance by dairy cows

Pelleting cottonseed (CS) improves handling characteristics. Our objectives were to determine whether increasing the particle size of the CS pellet or dilution of a smaller pellet with delinted CS would limit the rate of CS oil release to optimize digestibility of fatty acids (FA) and fiber while maintaining milk fat production. In a 5 × 5 Latin square design with 3-wk periods, 5 rumen-cannulated cows were fed 1) control with CS hulls (CSH) and CS meal plus tallow and Ca soaps of FA, 2) whole CS (WCS), 3) small CS pellets (SP; 0.44-cm die diameter), 4) larger CS pellets (LP; 0.52-cm die diameter), or 5) a blend of SP plus partially delinted CS (SPD). Diets contained 39.6% concentrate, 14.4% CS, and 46% forage (40:60, alfalfa hay:corn silage) on a DM basis and were balanced to have similar concentrations of CS protein, CS fiber, and total fat. In a production trial, dietary treatments were 1) WCS control, 2) LP, 3) SPD, and 4) SPD fed at 90%. Sixty cows averaging 105 d in milk were fed the WCS diet for 2 wk and then assigned to one of the 4 diets for 12 wk. Total tract digestibility of NDF was unaffected, but N digestibility was lower for SPD than for other treatments. Fatty acid digestibility was higher for SP and LP (82.6 and 82.3%) than for CSH or SPD treatments (78.8 and 75.3%), and WCS was intermediate (81.1%). The trans-11 C_18:1 from cows fed SP and LP (6.58 and 6.24% of total milk FA) was greater than that from cows fed CSH, WCS, and SPD (3.23, 3.79, and 3.97%). The trans-10 C_18:1 in milk fat from SP and LP (0.508 and 0.511%) was higher than that in WCS and SPD diets (0.316 and 0.295%); CSH was intermediate (0.429%). Using passage rates estimated from the NRC, disappearance of total FA in situ was estimated to be 17.7, 44.2, 46.6, and 35.0% for WCS, SP, LP, and SPD, respectively. In the production trial, a diet × week interaction was explained by a trend for progressively greater milk production for SPD and SPD90 than for WCS or LP. Milk fat was lower for LP (2.74%) and SPD90 (2.85%) than for WCS or SPD (3.07 and 3.08%). The fat yield was lower for LP than for SPD (1.09 and 1.30 kg/d); WCS and SPD90 were intermediate (1.23 and 1.21 kg/d). Although having a lower FA digestibility, SPD appeared to minimize negative effects of free oil from SP in the rumen, explaining higher DMI and milk production compared with WCS or LP.     

Release properties of cinnamaldehyde loaded by montmorillonite in chitosan-based antibacterial food packaging

This work aimed to prepare a controlled-release antibacterial food packaging film by solvent volatilisation using chitosan (CS) and acidified modified montmorillonite (MMt) loaded with CIN (acid-MMt-CIN). MMt was successfully acidified and CIN was successfully loaded into acid-MMt, which had been confirmed by X-ray diffraction. The coordination of acid-MMt-CIN significantly increased the barrier properties of CS film to water vapour, as well as the rigidity and ductility of the film. Furthermore, the CS/acid-MMt-CIN film could significantly improve their UV resistance. It was found that the CIN release time of CS/acid-MMt-CIN film in isooctane (simulated fatty food) could reach 168 h, which was 72 h longer than that of CS/CIN film. The addition of acid-MMt-CIN had a significant inhibitory effect on Staphylococcus aureus and Escherichia coli. In short, CS/acid-MMt-CIN film could potentially be used as an antibacterial active food packaging film.     

复合生物保鲜剂对金黄色葡萄球菌的抑菌作用研究

研究了壳聚糖、溶菌酶与茶多酚配制而成的复合保鲜剂对金黄色葡萄球菌的抑菌作用。采用琼脂平板打孔法确定复合保鲜剂对金黄色葡萄球菌的最小抑菌浓度(MIC)与最小杀菌浓度(MBC),结合抑菌率、抑菌活力、细菌生长曲线、膜完整性、AKP活性与细菌超微结构,综合评价复合保鲜剂对金黄色葡萄球菌的影响。结果得出,复合保鲜剂对金黄色葡萄球菌的MIC与MBC分别为0.8 mg/mL与1.6 mg/mL,随着作用时间的延长,复合保鲜剂对金黄色葡萄球菌的生长抑制明显,菌体的细胞壁与细胞膜完整性受到破坏,菌体细胞中的AKP量增多,影响菌体细胞的代谢循环,菌体内部的核酸与蛋白质外泄,抑制其正常生长。由细菌超微结构观察发现,菌体细胞经复合保鲜剂处理后,造成菌体扭曲变形,细胞壁破裂,细胞质外渗。表明复合保鲜剂可破坏菌体的细胞壁,影响胞膜稳定性与胞内环境,最终导致菌体死亡。     

Fabrication,characterization and antibacterial mechanism of in-situ modification nano-CaCO3/TiO2/CS coatings

In order to obtain the chitosan (CS) coatings with excellent physicochemical properties and antibacterial abilities, the CS coatings were modified by in situ modification nano-CaCO₃ and nano-TiO₂. The coatings were characterised, and their physicochemical properties were measured. The antibacterial mechanism of the coatings was investigated with the Shewanella putrefaciens and Pseudomonas aeruginosa. The nano-CaCO₃/TiO₂ can improve the tensile strength and elongation at break of the CS coatings. In addition, the carbon dioxide permeability of the CS coatings is increased after modification by nano-TiO₂. The nano-CaCO₃/TiO₂/CS coating can effectively disrupt the integrality of bacterial cell membrane and improve their permeability, reduce the cellular enzyme activities, and affect the synthesis and expression of the bacterial protein. Eventually, the growth and reproduction of S. putrefaciens and P. aeruginosa are inhibited. The in situ modified nano-CaCO₃/TiO₂/CS coatings have potential to be applied in the field of preservation of aquatic products.