Excel在微生物培养条件优化中的应用

根据正交试验设计的原理,采用Microsoft Excel软件编制优化微生物培养条件的程序,并以实例说明了该程序的使用方法。结果表明,用户只需输入试验的原始数据,即可快速、准确地进行直观分析和方差分析,并可根据极差值得出最佳工艺条件,从而大大提高微生物发酵的效率。     

超声波提取加拿大蓬总黄酮的研究

目的:研究加拿大蓬中总黄酮提取方法及最佳工艺.方法:采用超声提取法,通过单因素试验和正交试验筛选最佳工艺条件.结果:最佳提取条件为60%乙醇、料液比1:20、60 kW下超声45 min.得率为31.076 mg/g.结论:该方法提取提取总黄酮快速、简便,可适用于生产中加拿大蓬总黄酮类物质的检测.该方法是提取加拿大蓬总...     

芍药黄芩乳膏的临床前制备工艺研究

目的:探讨芍药黄芩乳膏的提取工艺.方法:以浸膏得率和芍药苷含量为考察指标,采用正交试验法,考察浸泡时间、加水量、提取次数、提取时间4个因素对提取工艺的影响.结果:最佳提取工艺为A3B3C3D2即药材加水10倍量,浸泡时间为1.5h,提取3次.提取时间为1.5h.结论:正交试验优选的芍药黄芩乳膏的提取工艺快速、准确、简便.     

石甘散散剂挥发油的提取工艺研究

目的:探讨石甘散散剂挥发油提取工艺,优选石甘散散剂挥发油提取方法,确定提取的最佳工艺条件。方法:利用正交试验法,以水蒸气蒸馏法提取石甘散挥发油,计算挥发油得率;并用高效液相色谱法,以面积归一化法计算石甘散挥发油中β-细辛醚的含量为指标,研究石甘散挥发油提取工艺中的影响因素;对提取时间、浸泡时间和加水量三个影响因素的试验结果进行分析,计算不同因素影响下的石甘散散剂挥发油得率及β-细辛醚的含量,从而优选出石甘散挥发油最佳提取工艺。结果:影响石甘散挥发油得率及β-细辛醚含量的最主要因素为提取时间,其次为加水量,再者为浸泡时间。结论:通过这三个因素影响下的正交试验结果,筛选出的石甘散散剂挥发油最佳提取工艺为加水量10倍,浸泡时间1小时,提取时间8小时。该提取工艺简单易行、合理稳定,为石甘散散剂挥发油的最佳提取工艺条件。     

金花茶叶中山奈酚的提取工艺优化及HPLC法测定

以HPLC为研究手段,应用正交实验、方差分析等方法对提取时间、加热回流温度、甲醇-0.4%磷酸比例进行优化,并以金花茶叶中的山奈酚为研究对象,建立不同种类的金花茶叶中山奈酚的定量方法。经过单因素和正交试验得出加热回流提取金花茶叶中山奈酚的最佳工艺为:加热温度为80℃,加热时间为100 min,甲醇磷酸比例为1:4。研究表明,该方法可快速准确对金花茶叶中山奈酚质量进行定量,且方法简单、灵敏度高、线性范围广。     

马铃薯渣中膳食纤维提取工艺的优化

目的：以马铃薯渣为原料,探究提取马铃薯渣中膳食纤维的最佳工艺条件。方法：通过生物法 酶法、超声波裂解、高速剪切等技术提取马铃薯渣中所含的膳食纤维,通过单因素试验和正交试验分析试验数据。 结果：提取膳食纤维的最佳工艺条件为酶解pH为5、酶解温度45℃、酶添加量30U/g、酶解2.5h。结论：本研究膳食纤维的提取率达25.87%,并测得持水力和膨胀力分别为7.1g/g、7.5mL/g,该工艺条件可有效提取马铃薯渣中的膳食纤维。     

块根紫金牛总黄酮提取工艺优化和不同产地、部位的含量比较

本研究采用正交试验分析和分光光度法,建立了块根紫金牛总黄酮含量测定的方法并比较分析其不同产地及不同部位总黄酮的含量差异.结果表明超声波法提取块根紫金牛中总黄酮的最佳提取工艺为:乙醇浓度60%,料液比1:70,提取时间50 min,提取功率200 W,提取温度70℃.另外,不同产地块根紫金牛中总黄酮含量顺序为:靖西＞那坡＞德保＞扶绥＞龙州＞武鸣;同一产地块根紫金牛根、茎、叶间总黄酮含量的高低顺序大致为:叶＞根＞茎.且通过精密度、重复性、稳定性和回收率实验来检测最佳提取工艺条件,结果显示该方法操作简便,结果准确,重复性好,RSD为0.788%,稳定性和回收率较高,平均回收率达96.20%.证明该方法可用于比较不同产地块根紫金牛药材中总黄酮的含量差异,对不同产地块根紫金牛的药材质量分析具有一定的指导作用.     

正交试验法优选复方四参颗粒剂的提取工艺

本文研究复方四参颗粒剂的提取工艺,采用正交试验法,以丹酚酸B提取率和干膏得率为指标,考察加水量、煎煮时间和煎煮次数对提取效果的影响,确立了复方四参颗粒剂的最佳提取工艺为:加8倍量水,提取2次,第一次时间为2 h,第二次为1 h。在最佳提取工艺条件下,干膏得率为16.58%,丹酚酸B的平均量为22.42mg。与正交试验的结果相符,说明该提取方法合理、稳定、可行。     

提取纯化大黄素的工艺研究

目的:为虎杖中大黄素的提取纯化工艺提供实验依据。方法:以乙醇浓度、乙醇用量、提取时间、提取次数等条件为因素,分别设计了三个水平,对大黄素的提取工艺进行正交试验。结果:大黄素的最佳提取工艺为虎杖药材加85%的乙醇回流提取3次,每次8倍量的溶剂提取1.5 h。结论:应用该提取工艺得到的大黄素的质量分数不低于10%     

葛根总黄酮提取工艺的研究

目的:筛选提取葛根总黄酮的最佳工艺条件。方法:采用单因素和正交试验对提取葛根总黄酮的工艺条件进行优化;利用紫外可见分光光度计测量葛根总黄酮的含量;利用高效液相色谱仪测量葛根素的含量;分别以葛根素和葛根总黄酮的含量为指标进行最优工艺的评价。结果:最佳工艺条件是以9倍量的30%乙醇提取3次,每次1h。结论:该提取工艺简单,成本低,适合于生产应用。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.