Bioassay-Guided Isolation of Two Eudesmane Sesquiterpenes from Lindera strychnifolia Using Centrifugal Partition Chromatography

In this study, a centrifugal partition chromatography (CPC) separation was applied to identify antioxidant-responsive element (ARE) induction molecules from the crude extract of Lindera strychnifolia roots. CPC was operated with a two-phase solvent system composed of n-hexane-methanol-water (10:8.5:1.5, v/v/v) in dual mode (descending to ascending), which provided a high recovery rate (>95.5%) with high resolution. Then, ARE induction activity of obtained CPC fractions was examined in ARE-transfected HepG2 cells according to the weight ratios of the obtained fractions. The fraction exhibiting ARE-inducing activity was further purified by preparative HPLC that led to isolation of two eudesmane type sesquiterpenes as active compounds. The chemical structures were elucidated as linderolide U (1) and a new sesquiterpene named as linderolide V (2) by spectroscopic data. Further bioactivity test demonstrated that compounds 1 and 2 enhanced ARE activity by 22.4-fold and 7.6-fold, respectively, at 100 μM concentration while 5 μM of sulforaphane induced ARE activity 24.8-fold compared to the control.

Major hydrogeological characteristics of thermal waters in Dalimammadli and Tarsdallar structures of Kur depression

Due to the drilling works carried out through 1970-1980s, the oil-gas bearing content of Dalimammadli and Tarsdallar structures has been studied. According to the conducted researches, thermal waters with high recovery rate and temperature more than 60 оC at the wellhead have been revealed. By chemical composition these waters are predominantly of chloride-sodium, and in Gazanbulag area – chloride-calcium (Са > 50 %) character. The main microcomponents are iodine, bromine, borium, etc. In this regard, the health centers (Goran, Gazanbulag, etc.) have been constructed in this area.

Gateway and Barriers of Forward Osmosis – A Mini Review

Forward Osmosis (FO) is a technique that requires less power consumption compared to other membrane techniques. FO is significant for its fouling resistance rate, energy consumption, high recovery rate, water flux and scourable. The FO membrane is fabricated by successive steps namely phase inversion via immersion precipitation followed by interfacial polymerization under suitable parameters. The application of FO in various fields can be enhanced by overcoming the limitations. This study shows the approaches of membrane fabrication for FO technique, applications, advancement in the current industries with limitations and overcoming solutions.

Development of new stability indicating UPLC-UV method for the extraction and quantification of perindopril and indapamide from human plasma

Background The hypertension and cardiovascular ailments are the leading cause of deaths worldwide. The combination therapy was found to be effective on the cardiovascular illness by reducing the blood pressure. The indapamide and perindopril combination therapy showed excellent results on reducing high blood pressure. With this in mind, the stability indicating reverse phase UPLC method was developed for the simultaneous identification and quantification of indapamide and perindopril from human plasma. In this work, we developed a new solid phase extraction method for the extraction of indapamide and perindopril in human plasma. It is a simple, accurate, and selective method for the extraction of these two drugs from human plasma with elution time of 2 min. The extracted drugs were identified and quantified by using stability indicating UPLC method. The method showed high recovery rate as well as low detection and quantification limits of two drugs. Results A novel, simple, highly accurate, and precise stability indicating ultra-performance liquid chromatography (UPLC) method was developed for the identification and quantification of perindopril (PP) (brand name Coversyl) and indapamide (IP) (brand name Lorvas) from human plasma. In this UPLC method, HSS C18 column (100 × 2.1 mm, 1.8 μm) and mobile phase acetonitrile (ACN), 10 mM KH2PO4 buffer solution (pH 3.0) mixture was used in the ratio of 65:35. Colum temperature of 30 °C, flow rate of 1.0 mL per minute and UV wave length of 254 nm were used. PP and IP were eluted below 2 min runtime with high resolution. Solid phase extraction (SPE) method was used for the extraction of PP and IP from human plasma. Different solvents were used to extract the analyte from SPE such as ACN, methanol, acetone, tertiary butyl diethyl ether (TBDE), chloroform (CHCl3), and ethanol (EtOH). Among these, ACN gave good recovery percentages (94.56 to 101.58%). From the linearity graph, good correlation coefficient values of 0.9996 for PP and 0.9997 for IP were achieved. The coefficient variance values for intra and inter day precision is in between 1.08 and 12.5%. The LOD and LOQ values were determined by the signal to noise ratio method. LOD and LOQ values for IP and PP were found to be 8.6 and 33.5 ng/mL and 28.33 and 110.5 ng/mL respectively. The developed method was statistically validated as per ICH guidelines. Conclusion In summary, a novel stability indicating UPLC-UV method was developed and validated for the simultaneous identification and quantification of perindopril and indapamide drugs in human plasma and tested the stability as per ICH guidelines. It is a simple, accurate, and specific method for the extraction of these two drugs from human plasma and eluted within 2 min runtime. The method showed high recovery rate as well as low detection and quantification limits of two drugs. The developed method is suitable for routine analysis as well as in bioanalytical and clinical studies. Graphical abstract

Behaviour of Ionic Liquid-Derived Naphthenate Salts Under Desalting Conditions

Pyrenees crude oil containing high napthenic acids (NAs) content of more than 1.6 mg KOH/g oil was treated with methyltrimethylammonium methylcarbonate [N4441][MeCO3] as to reduce its acidity to the refinery permissible limit of 0.3 mg KOH/g oil. The treated crude oils are subjected to Emulsion Stability Test (EST) as to mimic the operating conditions of a desalter. The results indicate the electrostatic conditions can facilitate the recovery of the napthenate salts post neutralization with high recovery rate of more than 79.6% with basic sediments & water (BSW) to be 1.96%. The conductivity of the treated crude oil also was found to increase as a function of temperature. The ionic liquid mediated-deacidification of crude oil can be performed under existing desalting conditions should the recovery of the naphthenate salts is acceptable at 70%.

Fundamentals of integrated ferrohydrodynamic cell separation in circulating tumor cell isolation

We present the fundamental theory and experimental validations of an integrated ferrohydrodynamic cell separation (iFCS) method that can isolate circulating tumor cells with a high recovery rate.

347 Choosing an external marker for measuring intake and digestibility in ruminants

Proper nutrition is key to maintaining and improving animal productivity. Measuring intake and site and extent of digestion is essential for appropriate diet formulation. However, it is extremely difficult to accurately account for the dynamic nature of the ruminant digestive tract. External markers have long been used as a tool to measure digesta output, yet proper marker selection can be challenging. The aim of this review is to provide guidance in the selection of external markers in ruminant nutrition studies. External markers must satisfy certain requirements in order to be considered a valid marker. These requirements include, but are not limited to, being inert in the gastrointestinal tract, mixing with the digesta, and having high recovery rate in the feces. In addition, laboratory analysis needs to be easily reproducible within and amongst laboratories. Health hazards of the marker must also be kept in mind for the laboratory worker and the animal. There are a number of elements that have been utilized as external markers. Currently in the literature, chromic oxide (Cr2O3), long-chain alkanes (C32 to C36) and titanium dioxide (TiO2) are the most commonly used external markers. Each have been extensively evaluated and have their own positive and negative attributes. Results comparing fecal recoveries has been extensively reported in various diets fed to large and small ruminants. Of the three most widely utilized external markers, all have demonstrated adequate fecal recoveries, reasonable estimates of total duodenal and fecal digesta flows or output. Therefore, the selection of the appropriate marker comes down to the ease and accuracy at which analysis can be conducted, dosage rate, minimum dosage frequency, and safety to the user and animal.

Significant Waning of Active Cases of Covid-19 With High Recovery After Three Months of Complete Lockdown: Plausible Implication On Emergence of Herd Immunity in The Population

COVID-19 is fast spreading around the globe in a highly contagious manner. Until date there are no therapeutic agents/vaccines developed which could control this highly infectious virus from spreading among human population. Our earlier studies showed that implementation of prolonged lockdown had a profound effect on the rate of spread of COVID-19 in the population. The observed increase in doubling time of COVID-19 with a high recovery rate following complete Lockdown reflected that protective immunity may be present in the population. In this article, the data from three months following completion of Lockdown was considered. The results reflected that there was a significant down trend in the rate of COVID-19 with high recovery rate reaching up to 83% of the affected cases of COVID-19 by September 30, 2020. The projection made from the data up to 30 November, 2020, pointed towards continued decrease in active cases of COVID-19. Concomitant with this result, the recovery from COVID-19 reached to ~90% by end of October, 2020. The significance of the above mentioned results with rapid fall in active cases from end of September 30, 2020, in spite of increased testing for COVID-19 in generating immunity against COVID-19 is discussed.