向日葵茎髓提取物的抑菌活性及机制

以向日葵茎髓为原料,制得3种不同极性向日葵茎髓提取物。采用琼脂扩散法测定3种不同极性向日葵茎髓提取物对4种受试菌的抑菌活性;并以其中的金黄色葡萄球菌和大肠杆菌为研究对象,探讨了乙酸乙酯萃取部位(EE)的抑菌机制。结果显示:不同极性萃取部位对4种受试菌均有一定抑制作用。其中,EE处理金黄色葡萄球菌和大肠杆菌的最低抑菌质量浓度(MIC)均为0.78 g/L,半数抑制质量浓度(IC50)分别为(1.11?0.01)和(1.59?0.03)g/L;抑菌作用与其总酚、总黄酮含量呈显著正相关性(P0.05)。通过SEM分析发现,EE处理引起菌体形态变化,破坏菌体的细胞膜结构;EE可增加金黄色葡萄球菌和大肠杆菌细胞膜结构的通透性,使菌体内的电解质、蛋白质、碱性磷酸酶向胞外泄露;应用4?,6-二脒基-2-苯基吲哚(DAPI)染色和荧光检测发现,EE能干扰细菌遗传物质(DNA)的复制,最终抑制受试菌增殖。     

8种中药提取物在膏霜类化妆品中的抑菌效能研究

采用纤维素酶法提取8种中药(丁香、鱼腥草、虎杖、黄连、大黄、细辛、甘草和黄芩),并采用滤纸片法和试管二倍稀释法研究8种中药提取物的抑菌效能。根据其抑菌作用进行复配研究,参考美国个人护理品委员会(PCPC)的抑菌效能测试方法对膏霜配方进行微生物挑战试验。结果表明,在8种中药提取物中,黄连提取物对金黄色葡萄球菌、铜绿假单胞菌和大肠埃希氏菌的抑制效果最好,其抑菌圈直径分别为(12.4±0.4),(11.4±0.6)和(10.7±0.2)mm,最低抑菌浓度(MIC)分别为31.25,31.25和15.625 g/L。当黄连和黄芩提取物在膏霜配方中的质量分数分别为0.8%和0.6%时,可较强地抑制细菌和真菌的生长,可通过微生物挑战试验。     

洋葱提取物抑菌活性研究

采用70%乙醇提取洋葱,将其提取液经过三种不同溶剂萃取,萃取物对土壤中的放线菌、细菌及真菌的抑菌活性进行实验研究,测定并比较不同萃取物对土壤放线菌、细菌、真菌的抑菌活性。对土壤放线菌、细菌、真菌抑制效果最好的溶剂萃取物分别为石油醚、乙酸乙酯、正丁醇,其抑菌率依次为51.1%,75.1%,77.3%。洋葱的不同溶剂萃取物抑菌效果不同,且同一萃取物对土壤不同种类微生物的抑制效率亦不同。     

60Co-γ射线辐照对人参药渣膜剂理化性质及抑菌活性的影响

考察了~(60)Co-γ射线辐照处理对提取皂苷后的人参药渣膜剂理化性质和抑菌活性的影响。采用~(60)Co-γ射线辐照处理人参药渣,通过扫描电镜观察药渣形貌;通过在药渣中加入聚乙烯醇、白芨胶、卡波姆等制备膜剂,测定其透气率、密度、吸水力、抗撕强度、pH值等理化性质;采用滤纸片法测定膜剂对金黄色葡萄球菌、枯草芽孢杆菌、表皮葡萄球菌、大肠杆菌和沙门氏菌的抑菌活性。结果表明,辐照处理后,药渣颗粒变小,膜剂的透气率、吸水力和抗撕强度均有一定程度提高,膜剂对枯草芽孢杆菌和表皮葡萄球菌的抑菌活性较高,最低抑菌浓度(MIC)分别为10 mg·mL~(-1)和5 mg·mL~(-1)。通过对细菌形态观察,推测辐照人参药渣膜剂的抑菌机理可能是辐照破坏了细菌的细胞壁和细胞膜,导致细胞通透性增加,进而使细胞内容物外泄,抑菌活性提高。     

不同超声辅助提取桂花黄酮及其抑菌性

为了探究桂花黄酮的最佳提取工艺及其对白色念珠菌的抑菌效果进行了以下实验：对超声提取法、超声辅助酶提取法和超声辅助双水相提取法提取桂花黄酮的提取率进行比较，选择提取率最高的方法，进行了单因素和响应面的工艺优化实验；采用超高效液相色谱-串联质谱（UPLC-MS/MS）对四个品种的桂花黄酮化合物进行了单体成分的鉴定；并测定了四个品种桂花黄酮对白色念珠菌的最小抑菌浓度（MIC）及其对菌体细胞膜完整性和生物膜形成的影响。结果表明，经超声提取桂花黄酮的提取率最高，经单因素和响应面实验优化后，其最佳提取条件为温度50 ℃，液固比17 mL/g，乙醇浓度52%，在此条件下，金桂、银桂、丹桂、四季桂的提取率分别为13.88%、8.79%、13.16%和10.28%；四种桂花黄酮对白色念珠菌的抑菌效果不同。其中，金桂的效果最好，MIC值为1.5 mg/mL，能够显著提高白色念珠菌细胞膜的通透性，导致细胞内容物流出，抑制生物膜的形成，抑制率最高可达46.59%。     

响应面法优化板栗苞中抑制痢疾杆菌活性成分的提取工艺

为提高板栗废弃物的资源利用率，以板栗苞为原料，探究其抑制痢疾杆菌活性成分的提取工艺。采用吸光光度法筛选板栗苞抑制痢疾杆菌活性成分的提取溶剂；以抑菌率为响应值，采用单因素实验结合响应面法优化板栗苞抑菌活性成分的提取工艺；采用二倍稀释法测定板栗苞各提取物的最低抑菌质量浓度（MIC），并采用吸光光度法研究其对细菌生长曲线的影响。结果表明，板栗苞的乙醇水提取物对痢疾杆菌的抑菌活性最好；板栗苞抑菌成分的最佳提取工艺为乙醇体积分数45%，料液比1∶20(g∶m L)，提取温度50℃；在该条件下，板栗苞提取物抑菌率为61.27%±2.60%,MIC值为3.2 g/L；乙酸乙酯相提取物MIC值为0.4 g/L，抑菌率达85%以上。     

扛板归不同溶剂提取物体外抑菌活性研究

目的：研究扛板归不同极性溶剂提取部位的体外抑菌活性。方法：使用不同极性溶剂分别对扛板归进行提取，得扛板归不同极性部位。采用牛津杯法和两倍稀释法测定提取物体外抑菌活性。结果：除醇沉物和水相残余物外，不同浓度的石油醚回流提取物、石油醚萃取物、三氯甲烷萃取物、乙酸乙酯萃取物和正丁醇萃取物对金黄色葡萄球菌和大肠埃希氏菌均有一定的抑菌作用，三氯甲烷萃取物(10 mg/mL)对金黄色葡萄球菌和大肠埃希氏菌最强的抑制效果，其抑菌圈分别为21.67 mm和23 mm,MIC均为0.312 mg/mL。结论：扛板归提取物具有良好的抑菌活性。     

马齿苋中抑制马拉色菌活性成分的提取工艺研究

采用超声波辅助提取法提取马齿苋中抑制糠秕马拉色菌的活性成分,通过纸片法测定其抑菌效果,并以抑菌效果为指标,采用单因素试验确定较佳提取工艺。结果表明,当提取温度为60℃,提取时间为50 min,料液比为1∶25(g∶mL),超声功率为210 W时,所得提取物的抑菌效果较佳,抑菌圈直径为(46.68±1.21)mm。通过理化反应对马齿苋提取物中的成分进行初步检识,结果表明马齿苋提取物中存在生物碱类、皂苷类、蛋白质多肽或氨基酸和糖类,可能含有鞣质及酚类、黄酮类和三萜类,不存在有机酸类。     

苦瓜中抑菌成分的提取方法研究

选择不同溶剂提取苦瓜中的抑菌物质,通过抑菌实验,找到合适的提取苦瓜中抑菌物质的方法。实验结果显示,苦瓜中抑菌物质的最佳提取工艺条件为使用85%乙醇作为提取剂,提取温度85℃,索氏提取时间6 h,料液比1∶30(V∶V),浓缩,石油醚脱色,正丁醇萃取,浓缩后以甲醇溶解。在此条件下提取的提取物具有较高的抑菌活性,抑菌效果为对金黄色葡萄球菌大于大肠杆菌;初提物经聚酰胺分离后,50%和70%的乙醇洗脱液很好的保留了抑菌活性,而10%、30%、95%的乙醇洗脱液抑菌效果不明显。定性分析表明,有效的抑菌提取物中同时含有皂苷类、黄酮类、酚类和有机酸等成分。     

地肤子抑菌活性成分筛选

以最小抑菌浓度为指标,采用二倍稀释法分别测试地肤子乙醇提取物中的石油醚相、乙酸乙酯相、正丁醇相和水相萃取物对4株细菌和5株植物病原菌的抑制作用;再对抑菌活性较强的萃取物进行分离纯化,通过二倍稀释法测试所分离化合物的抑菌活性,并对其结构进行表征。结果表明,正丁醇相萃取物的抑菌活性最强,从中分离得到3个化合物,其中化合物Ⅰ的抑菌活性较强,对大肠杆菌具有显著的抑制作用,其最小抑菌浓度为31.3μg·mL-1,经1 HNMR、IR及高分辨质谱等鉴定化合物Ⅰ为齐墩果酸。齐墩果酸有较强的抑菌活性,是地肤子抑菌活性的物质基础。     

焦油一次汽化温度计算方法的探讨

利用相平衡原理得出的焦油蒸馏时一次汽化温度的计算方法,其结果与按经验公式的计算结果进行了比较,同时讨论了一次汽化温度与焦油馏分产率及二段蒸发器过热蒸汽用量的关系。     

Efficacy for Whitlockite for Augmenting Spinal Fusion

Whitlockite (WH) is the second most abundant inorganic component of human bone, accounting for approximately 25% of bone tissue. This study investigated the role of WH in bone remodeling and formation in a mouse spinal fusion model. Specifically, morphology and composition analysis, tests of porosity and surface area, thermogravimetric analysis, an ion-release test, and a cell viability test were conducted to analyze the properties of bone substitutes. The MagOss group received WH, Group A received 100% beta-tricalcium phosphate (β-TCP), Group B received 100% hydroxyapatite (HAp), Group C received 30% HAp/70% β-TCP, and Group D received 60% HAp/40% β-TCP (n = 10 each). All mice were sacrificed 6 weeks after implantation, and micro-CT, hematoxylin and eosin (HE) staining, and Masson trichome (MT) staining and immunohistochemistry were performed. The MagOss group showed more homogeneous and smaller grains, and nanopores (<500 nm) were found in only the MagOss group. On micro-CT, the MagOss group showed larger fusion mass and better graft incorporation into the decorticate mouse spine than other groups. In the in vivo experiment with HE staining, the MagOss group showed the highest new bone area (mean: decortication group, 9.50%; A, 15.08%; B, 15.70%; C, 14.76%; D, 14.70%; MagOss, 22.69%; p < 0.0001). In MT staining, the MagOss group demonstrated the highest new bone area (mean: decortication group, 15.62%; A, 21.41%; B, 22.86%; C, 23.07%; D, 22.47%; MagOss, 26.29%; p < 0.0001). In an immunohistochemical analysis for osteocalcin, osteopontin, and CD31, the MagOss group showed a higher positive area than other groups. WH showed comparable bone conductivity to HAp and β-TCP and increased new bone formation. WH is likely to be used as an improved bone substitute with better bone conductivity than HAp and β-TCP.     

Techniques for screening adhesives for structural applications

—Due to its chemistry, no structural adhesive system (epoxies, acrylics, etc.) is likely to offer an ideal combination of toughness, strength, moisture resistance, and ambient-temperature curing. Therefore, for effective use of adhesives in primary structures, an engineer must be able to identify adhesives that represent an optimum compromise among the different properties. In this paper, we present techniques for screening high-strength, ambient-temperature-curing adhesives for (1) moisture resistance under sustained loading and (2) fracture resistance in a way that is directly related to joint performance.     

Nanomaterials for Antiangiogenic Therapies for Cancer: A Promising Tool for Personalized Medicine

Angiogenesis is one of the hallmarks of cancer. Several studies have shown that vascular endothelium growth factor (VEGF) plays a leading role in angiogenesis progression. Antiangiogenic medication has gained substantial recognition and is commonly administered in many forms of human cancer, leading to a rising interest in cancer therapy. However, this treatment method can lead to a deteriorating outcome of resistance, invasion, distant metastasis, and overall survival relative to its cytotoxicity. Furthermore, there are significant obstacles in tracking the efficacy of antiangiogenic treatments by incorporating positive biomarkers into clinical settings. These shortcomings underline the essential need to identify additional angiogenic inhibitors that target numerous angiogenic factors or to develop a new method for drug delivery of current inhibitors. The great benefits of nanoparticles are their potential, based on their specific properties, to be effective mechanisms that concentrate on the biological system and control various important functions. Among various therapeutic approaches, nanotechnology has emerged as a new strategy for treating different cancer types. This article attempts to demonstrate the huge potential for targeted nanoparticles and their molecular imaging applications. Notably, several nanoparticles have been developed and engineered to demonstrate antiangiogenic features. This nanomedicine could effectively treat a number of cancers using antiangiogenic therapies as an alternative approach. We also discuss the latest antiangiogenic and nanotherapeutic strategies and highlight tumor vessels and their microenvironments.     

甘氨酸生产废液的治理回收技术

针对国内甘氨酸生产厂家排放的工业废水中含有多种污染物(一定量的氯化铵、少量的乌洛托品及微量的甘氨酸)的特点,提出采用多效真空降膜蒸发系统兼热泵技术回收废液中的氯化铵,回收氯化铵后排放的冷凝水进入冷凝水净化系统进行处理的综合治理方案。此工艺克服了采用常规蒸发技术从低浓度氯化铵废液中提取氯化铵带来的能耗大、对设备腐蚀性强的缺点,本项治理技术不仅解决了工业废水对环境的污染,而且有较高的经济效益。     

工程建设项目全面造价管理要则

通过对工程建设项目特点剖析，提出了工程建设项目全过程造价管理、全要素造价管理、全风险造价管理、全团队造价管理等四项造价管理技术，针对其特点提出全面造价管理的管理技术要则，并提出要注重事前管理控制、项目信息的收集和加工、加强项目的动态性管理、重视项目管理的科学性和艺术性等各项要求。     

我厂脱碳双塔再生工艺改造小结

介绍了双塔再生工艺的原理、改造前后的工艺流程 ,运行情况 ,并对改造进行了经济效益分析。