Applicability of Dimedone Assays for the Development of Online Aldehyde Sensor in Seawater Flooding Systems

Biocides are oilfield chemicals that are widely used to control bacterial activity throughout the oil industry. A feasibility study has been explored to develop detection techniques for biocide batch treatments, preferably on-line and in real-time, for their potential use in seawater flooding system. Several methods to measure key components of the biocide formulation were investigated and reported in previous study [1]. The enzymatic activity of an immobilized acetylcholine esterase (AChE) on the column material was successfully inhibited by some model compounds, but not by the actual biocides commonly used in Saudi Aramco seawater flooding system. In this paper, an alternative assay for biocide detection in the Saudi Aramco seawater flooding system was investigated for its applicability for the development of on-line biocide sensor. The assay was based on the detection of aldehyde functionality in the biocide mixture through measurement of a fluorescent derivative formed in the reaction of aldehyde groups and dimedone in the presence of ammonium acetate. The reaction of aldehyde groups with dimedone was demonstrated in seawater matrix, and the formed fluorescent product was successfully measured. The results showed that the dimedone-based assay was very sensitive, and relatively straightforward to perform. The ruggedness test also indicated that the assay is sensitive to minor changes of various specific conditions of the method. It is concluded that the dimedone assay is suitable for further development of a real-time biocide monitoring system to detect the presence of biocide slugs in seawater flooding system. The development of an automated on-line biocide sensor based on dimedone assay is underway.

Optimizing Growth Conditions for Digoxin Production in Digitalis lanata Ehrh

Objective: Digoxin is a therapeutic cardenolide widely used to treat various heart conditions such as atrial flutter, atrial fibrillation and heart failure in both Western as well as Chinese medicine. Digoxin is extracted from cultivated Digitalis lanata Ehrh. plants, known as Mao Hua Yang Di Huang in Chinese medicine. This manuscript presents two studies that were conducted to optimize the cultivation conditions for digoxin production in the TCM Mao Hua Yan Di Huang in a greenhouse under GAP conditions.Methods: Two experiments were designed in which 4 growth conditions were compared. Levels of digoxin, gitoxin, digitoxin, α-acetyldigoxin, β-acetyl-digoxin were measured using HPLC-UV and compared between the conditions.Results: Normal soil, no CO_2 enrichment combined with a cold shock was found to be the optimal condition for producing digoxin in the first experiment. Gitoxin content was significantly lower in plants grown in this condition. Mechanical stress as well as the time of harvesting showed no statistically significant differences in the production of cardenolides. In the second experiment the optimal condition was found to be a combination of cold nights, sun screen, fertilizer use and no milled soil.Conclusion: This study shows that digoxin production can be increased by controlling the growth conditions of D. lanata Ehrh. The effect of cold was important in both experiments for improving digoxin production. Cultivating Chinese herbal medicines in optimized greenhouse conditions might be an economically attractive alternative to regular open air cultivation.

Systems biology of resilience and optimal health:integrating Chinese and Western medicine perspectives

Western science has been strong in measuring details of biological systems such as gene expression levels and metabolite concentrations, and has generally followed a bottom up approach with regard to explaining biological phenomena. Chinese medicine in contrast has evolved as a top down approach in which body and mind is seen as a whole, a phenomenological approach based on the organization and dynamics of symptom patterns. Western and Chinese perspectives are developing towards a ‘middle out' approach. Chinese medicine diagnosis, we will argue, allows bridging the gap between biologists and psychologists and offers new opportunities for the development of health monitoring tools and health promotion strategies.In this paper, health, resilience and stress concepts are explored from an integrated systems biology perspective. This is followed by a discussion about measuring aspects of health and resilience. Then the issue of how to integrate different types of data is discussed. Semi-quantitative modeling appears to be very suitable and looks promising for building integrated health models. The challenge for the future lies in applying those models in developing personalized health monitoring and advice systems that will tempt people to lead more healthy lives.