Biological oyster shell waste enhances polyphenylene sulfide composites and endows them with antibacterial properties

To date,there is no research that deals with biological waste as fillers in polyphenylene sulfide(PPS).In this study,oyster shells were recycled and treated to prepare thermally-treated oyster shells(TOS),which were used as PPS fillers to make new bio-based antibacterial composite materials.The effect of varying the content of TOS was studied by means of structure and performance characterization.PPS/TOS composites were demonstrated to have an antibacterial effect on the growth of E coli and S.aureus.Qualitative analysis showed that when the TOS content was≥30%and 40%,the composite materials had an apparent inhibition zone.Quantitative analysis showed that the antibacterial activity increased with the TOS content.Fourier transform infrared spectroscopy indicated the formation of hydrogen bonds between the molecular chains of TOS and PPS and the occurrence of a coordination reaction.At 10%TOS,the composite tensile strength reached a maximum value of 72.5 MPa,which is 9.65%higher than that of pure PPS.The trend of bending properties is the same as that of tensile properties,showing that the maximum property was reached for the composite with 10%TOS.At the same time,the crystallinity and contact angle were the highest,and the permeability coefficient was the lowest.The fatigue test results indicated that for the composite with 10%TOS,the tensile strength was 23%lower than static tensile strength,and the yield strength was 10%lower than the static yield strength.The results of the study showed that TOS not only could reduce the cost of PPS,but also could impart antibacterial properties and enhance the mechanical and,barrier properties,the thermostability,as well as the crystallinity.

Particle Sizes and Antibacterial Activity of Radix Astragalus and Radix Isatidis Ultrafine Powders

Using 9200 laser particle size analyzer and KYKY-2800 scanning electron microscope, particle sizes and cellular morphology of Radix Astragalus and Radix Isatidis ultrafine powders were observed. According to the results, the particle size of 89. 1 % of Radix Astragalus ultrafine powders ranged from 1.729 [xm to 44.938 ｜xm, Z ）50 =4.368 ｜xm; the particle size of 93.411% of Radix Isatidis ultrafine powders ranged from 1.510 [xm to 44.938 ｜xm, Z ）50 = 8 .7 2 6 [xm. Radix As-tragalus and Radix Isatidis ultrafine powders were pulverized completely without intact cellular morphology. The antibacterial activity of Radix Astragalus and Radix Isatidis ultrafine powders against chicken-derived E. coli （078） was investigated. The results indicated that Radix Astragalus and Radix Isatidis ultrafine powders exhibited higher antibacterial activity against chicken-derived E. coli （078 ） compared with the corresponding coarse powders. This study laid a solid foundation for the development and application of Chinese medicine ultrafine powder preparations.

Preparation of titanium dioxide/silver sulfate powder and its antibacterial activity

Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the structure and composition of the product were investigated through XRD and SEM. The results show that the powder is spherical in the phase of TiO2-Ag2SO4. The granularity of the particles increases from 10.7nm to 28.7nm with the temperature of heat-treatment increasing from 300℃ to 800℃. The antibacterial activity of the powder was judged in the way of the minimum inhibitory contents （MiCs）. When the content of silver sulfate is less than 2%, the photocatalysis of titanium dioxide and silver ions cooperate to kill bacteria. And the MiCs decrease and keep around 1.0×10 -41.5×10 -4 constantly with the increase of silver content. Furthermore, the MiCs decrease with the increase of temperature of heat-treatment when the temperature is lower than 500℃. But when the temperature is beyond 600℃ the MiCs increase quickly, which shows the inferior antibacterial performance.

Preparation of doping titania antibacterial powder by ultrasonic spray pyrolysis

Doping titania powders were synthesized by ultrasonic spray pyrolysis method from an aqueous solution containing H2TiF6 and AgNO3.The effects of the processing parameters on particle size distribution,structure,and morphology of doping particles were investigated.The results show that aggregation-free spherical particles with average diameter of 200-600 nm are obtained and the particle size of the powder can be controlled by adjusting the concentration of solution.The experimental approach indicates that the size and the value of standard deviation of particle size increase from 210 nm to 450 nm and from 0.46 to 0.73 respectively with the increase of the titanic ion concentration from 0.05 to 0.4 mol/L.Composite TiOF2 is obtained when the pyrolysis temperature is set to be 400 ℃.With increasing pyrolysis temperature from 400 ℃ to 800 ℃,the crystal size of titania powders increases from 14.1 to 26.5 nm and TiOF2 content of powder decreases dramatically.The property of ion released from powder is affected significantly by the pyrolysis temperature,and the amount of fluorine ion and silver ion released from powder decrease with increasing pyrolysis temperature.The optical property of doping titania powders is not affected by pyrolysis temperature.Antibacterial test results show that composite powders containing more fluorine ions exhibit stronger antibacterial activity against E.coli.

响应面法优化超声波辅助提取公英散工艺参数及其抑菌和抗氧化性能研究

本试验旨在通过响应面法优化超声波辅助提取公英散工艺参数,并对公英散水提物的体外抗氧化和抑菌活性进行测定。通过单因素试验确定各因素的取值范围,用Plackett-Burman设计并筛选出超声温度、超声时间、液料比3个显著影响公英散提取效率的因素,然后采用Box-Behnken响应面分析法得出最佳提取条件。通过微量肉汤稀释法和Kirby-Bauer纸片扩散法评价公英散水提物体外抑菌活性,采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法和羟自由基清除法研究公英散水提物体外抗氧化活性。结果表明:在超声波功率420 W、超声温度80℃、超声时间65 min、液料比37∶1时,公英散的提取效率最高。公英散水提物对3种奶牛乳房炎临床致病菌都有不同程度的体外抑制作用,对大肠杆菌(E.coli)的最低抑菌浓度(MIC)为9.00 mg/mL,最低杀菌浓度(MBC)为18.00 mg/mL;对无乳链球菌(S.agalactiae)的MIC为4.50 mg/mL,MBC为9.00 mg/mL;对金黄色葡萄球菌(S.aureus)的MIC为2.25 mg/mL,MBC为4.50 mg/mL。此外,当公英散水提物浓度达到1.00 mg/mL时,对羟自由基(78.70%)和DPPH自由基体外清除率(75.63%)良好。综上所述,本试验成功筛选出了公英散的最佳提取工艺条件,且所得公英散水提物有良好的体外抗氧化活性,并对3种奶牛乳房炎临床致病菌均有不同程度的体外抑菌活性。

Cu含量对多孔Ti-5Mn合金微观结构及力学性能的影响

以质量分数为50%的碳酸氢铵颗粒为造孔剂,使用粉末冶金工艺经真空烧结制备出多孔Ti-5Mn-xCu(x=0,3,5,10)合金,并研究了Cu含量对多孔Ti-5Mn合金微观结构及力学性能的影响。研究结果显示,制备得到的多孔Ti-Mn-Cu合金的孔隙率随着Cu含量的增加而逐渐降低,其大孔孔径略为减小,大孔壁上微孔数量逐渐减少。多孔Ti-Mn-Cu合金中出现了Ti_(2)Cu相,并且其相对含量随着Cu含量的增加逐渐增多。多孔Ti-Mn-Cu合金的弹性模量和抗压强度均随Cu含量的增加而提高。含3%~10%Cu和5%Mn的多孔Ti-Mn-Cu合金具有合适的孔结构和与人体骨相近的力学性能,具有作为抗菌骨科植入材料的潜力。

抗菌耐寒PVC花洒软管配方研究

通过己二酸聚酯和粉末丁腈橡胶(PNBR)的复配作用,改善PVC增塑剂迁出和软管低温硬化问题,同时在交联剂双叔丁基过氧异丙基苯(BIPB)作用下,将抗菌剂聚六亚甲基双胍盐酸盐(PHMG)以化学键的形式键合到PVC的分子链上使得材料具有长效抗菌功能,制成一种抗菌耐寒PVC材料,并成功试产了PVC复合软管。经过探索找到最合适的配方和工艺,检测结果显示采用本配方生产的PVC花洒软管,对金黄色葡萄球菌和大肠杆菌的抑菌率均超过99.5%,老化测试后仍不低于98%;0℃低温下邵氏硬度比邻苯二甲酸酯类增塑剂(DOP)配方低9 HA,拉伸强度比低分子耐寒增塑剂(DOA)高2.9 MPa。

抗菌耐寒PVC花洒软管配方研究

在交联剂双叔丁基过氧异丙基苯(BIPB)作用下,将抗菌剂聚六亚甲基双胍盐酸盐(PHMG)以化学键的形式键合到聚氯乙烯(PVC)的分子链上;同时通过己二酸聚酯和粉末丁腈橡胶(PNBR)的复配作用,制成一种抗菌耐寒PVC材料,并试产了PVC复合软管。检测结果显示:采用本配方生产的PVC花洒软管,对金黄色葡萄球菌和大肠杆菌的抑菌率均超过99.5%,老化测试后仍不低于98%;0℃低温下邵氏硬度比邻苯二甲酸酯类增塑剂(DOP)配方低9 A,拉伸强度比低分子耐寒增塑剂己二酸二辛酯(DOA)高2.9 MPa。

Sanchen powder extract combined with vancomycin against methicillin-resistant Staphylococcus aureus

Objective: To explore the effects of the extract of Sanchen powder(ESCP) combined with vancomycin on methicillin-resistant Staphylococcus aureus(MRSA) planktonic cells, biofilms, and virulence factors.Methods: The herbs in Sanchen powder(SCP) were extracted separately with 50% ethanol. Then, the content of hydroxysafflower yellow A(HSYA) and cholic acid in the extract of artificial cattle bezoar(artificial Calculus bovis) and safflower(Carthamus tinctorius L.) was measured by ultraviolet visible-vis spectrophotometry and high-performance liquid chromatography. The effects of ESCP combined with vancomycin on MRSA by observing its biofilm viability were assessed using a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium5-carboxanilide reduction assay and scanning electron microscopy.Additionally, enzyme activity was measured by plasma coagulase test and DNase test.Results: The cholic acid content of the artificial C. bovis extract was 7.34(0.81) mg/g, and the HSYA content of the C. tinctorius extract was 9.18(0.09) mg/g. The minimal inhibitory concentrations of ESCP and vancomycin were 25.6 mg/m L and 2 μg/m L. The minimum bactericidal concentration of ESCP was51.2 mg/m L. ESCP combined with vancomycin could inhibit the expression of coagulase and bacteria in mature biofilms. Neither ESCP nor vancomycin had a significant effect on DNase.Conclusion: This study is the first to show that ESCP combined with vancomycin inhibits coagulase and MRSA embedded in mature biofilms and that it represents a promising treatment for MRSA infection.

红曲米粉在软欧包的着色研究

为探究红曲米粉在软欧包着色及应用,设置五个条件(常温曝光、常温避光、冷藏曝光、冷藏避光、冷冻避光)贮藏,采用单因素和正交试验法,考察添加红曲米粉对成品口感、色差、质构、风味物质、抑菌影响。研究发现:添加0.5%红曲米粉,在pH8,95%乙醇浓度,冷冻避光贮藏,软欧包感官、色泽、质构、风味、抑菌最佳。不同条件贮藏33 d,软欧包L^(*)、b^(*)值增大,a^(*)值减小;第一循环硬度增大;弹性减小;风味独特;常温曝光、常温避光贮藏,第4 d已霉变;冷藏曝光、冷藏避光、冷冻避光贮藏至第33 d,菌落总数和霉菌均未超标,抑菌效果良好。红曲米粉在软欧包中具有强着色、抑菌作用,应用前景大,为新型天然色素在烘焙产品应用开发新路径。

Cu含量对Zn-2.0Mg-xCu合金组织与性能的影响

采用粉末冶金技术制备了Zn-2.0Mg-xCu合金,研究Cu元素对于Zn基合金显微组织、力学性能、耐腐蚀性能和抗菌性能的影响。结果表明:Zn-2.0Mg-xCu合金(x=0.5wt%~2.0wt%)均由η-Zn相和Mg_(2)Zn_(11)相组成,随着Cu含量的增加,Zn-2.0Mg-xCu合金中的孔隙增多,显微硬度和抗压强度均出现先增加而后降低的现象。380℃烧结2 h后Zn-2.0Mg-1.5Cu合金的显微硬度和抗压强度达到最大,为77.3 HV和126.7 MPa。随着合金中Cu含量的增加,Zn-2.0Mg-xCu合金的维钝电流密度、腐蚀速率和失重均增加,人工模拟体液腐蚀浸泡14 d后,Zn-2.0Mg-xCu合金表面逐渐出现明显的腐蚀坑。对Zn-2.0Mg-xCu合金进行的抗菌性研究结果表明:Zn-2.0Mg-xCu合金对金黄色葡萄球菌和大肠杆菌均表现出良好的杀灭和抑制增殖效果,随着Cu含量的增加,Zn-2.0Mg-xCu合金的抗菌效果越明显。

纳米磷酸锆载银抗菌聚酯纤维的制备工艺

采用银离子络合交换技术,引入促进剂和双表面活性剂,制备了粒径可控、抗菌效果好且耐久的抗菌粉体和母粒,将其用于制备182 dtex/72 f吸湿排汗抗菌涤纶预取向丝(POY),通过优化母粒制备、纺丝温度、无风区高度、卷绕等工艺参数,成功制备满足后道高品质运动面料需求的抗菌纤维。

清胃散治疗牙周病的网络药理分子机制探讨

目的利用网络药理学和分子对接技术解析清胃散治疗牙周病的作用机制。方法借助中药计算系统生物学实验室数据库和中医药百科全书数据库检索清胃散的化学成分和潜在作用靶点,利用Gene数据库查询与牙周病相关的基因。在STRING 11.0平台进行蛋白互作分析,通过DAVID 6.8数据库进行基因本体功能富集分析和基于京都基因与基因组百科全书生物通路富集分析。采用CytoSape 3.6.1软件构建可视化网络。利用分子对接技术验证关键活性成分和关键靶点的结合活性。结果清胃散方中关键药味是黄连、牡丹皮、升麻,关键活性成分是山柰酚、阿魏酸、维斯阿米醇、儿茶素、黄连碱、小檗碱、小檗红碱、藁本内酯,关键作用靶点是前列腺素G/H合成酶2、一氧化氮合酶3、一氧化氮合酶2、白细胞介素6和肿瘤坏死因子,主要调控肿瘤坏死因子信号通路和细胞因子-受体相互作用。结论本研究初步明确了清胃散通过多成分、多靶点、多通络治疗牙周病的药效作用机制,为深入研究清胃散的药效物质基础和作用机制提供参考。

文冠果奶茶片的研发与抑菌活性测定

本文以文冠果茶粉、奶粉、麦芽糊精等为原料,采用单因素和响应面试验,开发了文冠果奶茶片,并研究其对大肠杆菌及金黄色葡萄球菌的抑菌作用。结果表明:奶茶片的最佳配方为文冠果茶粉5%、奶粉40%、赤藓糖醇7%、维生素C 3%、麦芽糊精42%、硬脂酸镁3%;此配方制成的文冠果奶茶片感官评分为82.16,平均硬度为75.6 N,成粒率≥96%,片重差异±3.9%,脆碎度为0.2%,体外抑菌实验表明文冠果奶茶片对大肠杆菌和金黄色葡萄球菌有较好的抑菌效果。

钼酸银对粉末涂料性能的影响

为利用钼酸银的抗菌效果,与粉末涂料混合制备出一种新型涂料,采用DSC分析、耐酸碱测试、接触角测试、涂层的铅笔硬度和附着力测试、抗菌实验对涂料进行性能测试,结果表明,当钼酸银含量为0.18 wt.%时,钼酸银抗菌粉末涂料的综合性能优异,并且对大肠杆菌和金黄色葡萄球菌的抗菌率达到100%。钼酸银抗菌粉末涂料具有优异的物理性能和抗菌效果,同时无毒无害,不会对环境造成污染,具有广阔的应用前景。

无机抗菌粉体中银价态与抗菌性能研究

以SiO2 为基体 ,Ag+ 作为主要抗菌成分的无机抗菌剂粉体 ,控制银离子的含量为n(Ag)∶n(Si) =0 .0 2 86时 ,在无机抗菌剂中分别引入摩尔分数约 3 0 %的Al3+ 或 60 %的Zn2 + ,用于稳定无机抗菌剂中银价态 ,制备出不变色的无机抗菌粉末。利用XPS技术分析和抗菌性能测试 ,研究不同温度下抗菌粉体的抗菌性能和银价态关系 ,揭示含银无机抗菌剂银价态和抗菌性能关系及其机制。研究发现 :银离子的价态对粉体的抗菌性能影响很大 ,当银离子以AgO状态存在时 ,粉体的抗菌性能较好 ,若为银单质存在 ,则抗菌性能下降。Zn2 + 的加入 。

纳米复合抗菌剂在粉末涂料中的应用

制备了添加有复合纳米抗菌剂的粉末涂料,试验表明抗菌粉末涂料在涂膜附着性、力学性能、耐酸碱性、耐候性等方面都符合行业标准,所制备的抗菌粉末涂料具有良好的抗菌效果,能够满足涂料行业的使用要求。

海带提取物的鉴定及抗菌活性的研究

本实验以海带为原料,用四种不同的溶剂(蒸馏水、甲醇、正丁醇、乙酸乙酯)对其进行萃取,并通过正交试验得到海带各种提取物的最佳提取工艺,用高效液相色谱对这四种提取物结构进行初步表征,结果表明:海带粉提取物含有多种糖类化合物;对这四种提取物进行抗菌活性的研究表明这四种提取物在一定浓度下对枯草芽胞杆菌、大肠杆菌、四联球菌和金黄色葡萄球菌均有较明显的抑制作用,在稀释后仍然对上述菌种显示出一定的抑制作用。其中以乙酸乙酯提取物对枯草芽孢杆菌抑菌效果最明显。

海藻粉和抗菌肽及其协同效应对蛋鸡生产性能与蛋品质的影响

本试验旨在探讨海藻粉和抗菌肽及其协同效应对蛋鸡生产性能与蛋品质的影响。采用4×2(海藻粉×抗菌肽预混剂)完全随机试验设计,将480只海兰褐蛋鸡随机分为8个组,每组5个重复,每个重复12只。饲粮海藻粉的添加水平分别为0、1.0%、3.0%、5.0%,抗菌肽预混剂的添加水平分别为300、600 mg/kg。预试期7 d,正试期28 d。结果表明:1)饲粮添加海藻粉显著提高了产蛋率、蛋料比、蛋黄颜色和蛋壳强度(P<0.05)。2)饲粮添加抗菌肽显著提高了产蛋率和蛋壳强度(P<0.05)。3)海藻粉和抗菌肽协同效应显著提高了产蛋率、蛋料比、蛋黄颜色和蛋壳强度(P<0.05)。由此可见,海藻粉和抗菌肽对蛋鸡生产性能与蛋品质的影响存在协同效应,以5%海藻粉+300 mg/kg抗菌肽最为理想。