Expression of Beta-1,3-Glucanase gene in Escherichia coli

在本实验中，来自酿酒酵母HS1185的胞外－1，3－葡聚糖基因被插入TA克隆载体pMD-18中，并被转入大肠杆菌JM109中。重组质粒命名为pMDT-18-GLU。通过XhoI和NcoI双酶切质粒pMDT-18-GLU获得的－1，3－葡聚糖基因片段插入pET22b(+)的XhoI和NcoI酶切位点。此重组质粒命名为pET22b/GLU。质粒pET22b-GLU被转入大肠杆菌BL21(DE3)，通过菌落PCR筛选出阳性克隆。 提取出来已经插入Beta－1，3－葡聚糖基因的pET22b-GLU质粒和pET22b(+)通过PCR扩增和限制性内切酶验证分析。PCR质粒...In this study the exo--1,3-glucanase gene (GenBank Accession No. X59259; EC No. 3.2.1.58) from Saccharomyces cerevisiae strain HS1185 was ligated with TA cloning vector pMDT-18 and transformed into Escherichia coli strain JM109. The constructed plasmid was named pMDT-18-GLU. Plasmid pMDT-18-GLU was digested with Xho I and Nco I restriction enzymes and the obtained fragment of -1,3-...学位：工学硕士院系专业：化学化工学院化学工程与生物工程系_化学工程学号：2062007115407

Microbial production of D-lactic acid from dried distillers grains with solubles

D-Lactic acid production is gaining increasing attention due to the thermostable properties of its polymer, poly-D-lactic acid (PDLA). In this study, Lactobacillus coryniformis subsp. torquens, was evaluated for its ability to produce D-lactic acid using Dried Distillers Grains with Solubles (DDGS) hydrolysate as the substrate. DDGS was first subjected to alkaline pretreatment with sodium hydroxide to remove the hemicellulose component and the generated carbohydrate-rich solids were then subjected to enzymatic hydrolysis using cellulase mixture Accellerase® 1500. When comparing separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) of L. coryniformis on DDGS hydrolysate, the later method demonstrated higher D-lactic acid production (27.9 g/l, 99.9% optical purity of D-lactic acid), with a higher glucose to D-lactic acid conversion yield (84.5%) compared to the former one (24.1 g/l, 99.9% optical purity of D-lactic acid). In addition, the effect of increasing the DDGS concentration in the fermentation system was investigated via a fed-batch SSF approach, where it was shown that the D-lactic acid production increased to 38.1 g/l and the conversion yield decreased to 70%. In conclusion, the SSF approach proved to be an efficient strategy for the production of D-lactic acid from DDGS as it reduced the overall processing time and yielded high D-lactic acid concentrations

Nursing interventions in preventing obstetric fistula in adolescents in East Africa

Women in developing countries, particularly young girls experience difficult childbirth which results in the loss of their babies and a significant injury to their sexual and reproductive organs, a condition called obstetric fistula. According to the World Health Organization, an estimated 2 million women in sub-Saharan Africa, Asia, the Arab region, and Latin America and the Caribbean are living with this injury, and some 50,000 to 100,000 new cases develop each year. Statistics from United Nations Population Funds (UNFPA) presents that nine out of ten births are from adolescent girls and these births occur with a marriage or a union. Cultural practices of early marriages and early deliveries present a major risk factor for the development of obstetric fistula (OF) as a result of obstructed labour. Sub-Saharan Africa has the highest prevalence of teenage pregnancies in the world. Births to teenage mothers account for more than half of all the births in the region with an estimate of 101 births per 1000 women aged 15 to 19. The purpose of this thesis was to describe nursing interventions that have been and could be used in the prevention of obstetric fistula in adolescents in East Africa. Literature review methodology was used. 16 articles were retrieved from EBSCOHOST and PROQUEST databases by use of inclusive and exclusive criteria. Inductive content analysis was used to analyse the data which gave rise to several sub-categories and further narrowed to two main categories for interventions which have been done and two main categories for interventions which could be used to prevent OF in adolescents. The results showed that although there has been efforts to prevent obstetric fistula, more resources are aimed at treatment and management of obstetric fistula among women, not adolescents as a high-risk group. Findings also indicate that there is need to educate more nurses and midwives specialized in fistula prevention. There were also recommendations of what should be done in the prevention of obstetric fistula. Preventive measures for obstetric fistula should aim for root causes which provide long-term and sustainable solutions. Further research is recommended on obstetric fistula prevention in adolescents, defining the role of nursing intervention as an important component

Increasing Compliance with Company rules in a multi-cultural group of floor workers. Case company: Caternet Finland Oy

This thesis is a piece of research done whilst working for Caternet Finland Oy, a food company located and operating in Helsinki, Finland. The thesis originates from the researcher’s experience in the company. While working for the company the author realized a problem with in-house compliance of company rules, mainly when it comes to the floor workers. The main objective of my research was to study how Caternet Finland Oy can increase internal compliance within its multi-cultural group of floor workers through improving the communication of rules and regulations. The purpose is therefore to detect weaknesses and loopholes in the entire structure, but mainly in the communication of company rules to the multi-cultural group of shop floor workers. The research was carried out by using the qualitative research method. The data was collected through face to face interviews by the researcher himself. The interviews followed major themes, which included the following: rules and compliance employee communication and intercultural communication. The results revealed that rules in Caternet Finland Oy are formulated from what the law stipulates, customer demands and what the management wants. There has not been through communication of these rules to floor workers. The few rules which have been communicated have not effectively reached the entire group of floor workers. The research concludes that even though there are weaknesses in the formulation of rules, the company has more problems in the communication of rules to the workers. Intercultural communication has been viewed as the most urgent area for the company to check in order to achieve compliance from its multicultural group of floor workers. Suggestions are given for the company on how to improve the communication of rules

Kinetic studies of lactic acid production from wood extract hydrolysate via batch and continuous fermentation processes

The research work presented in this dissertation describes kinetic studies of batch and continuous fermentation of hemicelluloses to lactic acid. Sugar maple wood chips were subjected to hot water to extract hemicelluloses, predominantly as oligomers. Hemicelluloses oligomers were hydrolyzed to fermentable monomeric sugars by dilute acid hydrolysis and concentrated by nanofiltration process. The concentrated wood extract hydrolysate contained 138.7 g/L xylose, 22.2 g/L mannose, 18.7 g/L glucose, 10.7 g/L galactose, 4.6 g/L arabinose, and 5.2 g/L rhamnose. The effect of initial sugar loading was investigated by diluting the concentrated wood extract hydrolysate to obtain desired total sugar concentrations. In the batch fermentation process lower total sugar concentration led to the highest lactic acid yield of 0.83 g/g using Lactobacillus pentosus ATCC 8404 cells. Acetic acid was produced as the byproduct. Adaptation of Lactobacillus pentosus strain to concentrated wood extract hydrolysate led to 10 h reduction in batch fermentation time and 15.5% increase in lactic acid production. Adapted Lactobacilus pentosus cells were used to study the kinetics of lactic acid production via batch and continuous fermentation processes. The continuous fermentation process led to higher lactic acid productivity and lower acetic acid to lactic acid ratios ranging between 0.27 and 0.60 as compared to the batch fermentation process which had 0.62 acetic acid to lactic acid ratio. For both batch and continuous fermentation processes all wood hemicellulosic sugars were utilized with glucose being the preferred sugar whereas the rest of sugars were simultaneously utilized. A kinetic model for batch lactic acid fermentation from hemicellulosic sugars was developed. Kinetic parameters were determined by ODEXLIMS routine to solve a set of ordinary differential equations for biomass growth rate, product formation rate and substrate utilization rate while minimizing the variance between experimental and predicted values using Microsoft Excel ® solver. The model performed satisfactorily for predicting the transient responses of biomass growth, product formation and substrate utilization with squared Pearson correlation coefficient (R2) ranging between 0.97 and 0.99 for the initial substrate (total hemicellulosic sugar) concentrations of 40.0 g/L and 55.0 g/L

Characterization and treatment effects on Mutaka kaolin for additive in coatings: Mineral composition, thermal and structural modifications

Previous studies in Uganda have primarily explored kaolin's applications in composites, pottery, bricks, and insulation, neglecting its potential for coatings and paints, which is crucial for industrialization and saving foreign exchange. This study investigates the transformation of kaolin through various treatments and analyzes their impacts on its physical and chemical properties for potential use in coating applications. Thermal analysis, X-ray Fluorescence Spectroscopy (XRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and transmission electron microscopy (TEM) techniques were employed to assess these alterations. The results show that thermal treatment of kaolin at 45.9 °C had minimal impact on mass loss, while the crystallinity of kaolinite was found to be lost around 600 °C, resulting in structural changes. XRF result demonstrates variations in SiO2 and Al2O3 composition, with low TiO2 content desirable for paint and coating applications. XRD results showed well-defined diffractions associated with kaolinite in all treated and untreated kaolin samples. The presence of K-feldspar and quartz are also identified. However, the thermal treatment at 800 °C transforms kaolinite into metakaolin, essential for enhancing coating properties. SEM-EDS results indicate increased porosity and reduced impurities in the thermal-treated sample, which might enhance the whiteness and suitability of pigment and binder dispersion in coatings. TEM images confirmed the hexagonal nature of kaolinite platelets and demonstrated the amorphous nature of kaolin nanoparticles with ammonium molybdate treatment, which led to the delamination and exfoliation of kaolinite layers, improving dispersibility. Kaolin thermally treated exhibited good crystallinity, solid growth, cubic morphology, and uniform size distribution. These findings suggest that tailored treatments can optimize kaolin's properties, making it a promising additive for high-performance coatings