DCH18C6 using strontium extraction selectivity investigation and sequential soil fractionation study

85Sr as radioindicator has been applied to strontium separation selectivity study using cisdicyclohexano-18-crown-6 (DCH18C6) as extraction agent and picric acid as counter ion with the aim to contribute to the development of a rapid method of strontium extraction. The same radioindicator has been used for strontium fractionation study in chosen soils by application of Tessier- and BCR sequential extraction procedures. Experimental results have shown, that the mentioned extraction system is applicable for IDA determination of Sr2+ in ∼1000-fold abundance of Ca2+, ∼1000-fold abundance and Mg2+, ∼10-fold abundance of K+ and ∼0.2-fold abundance of Ba2+. For the soil samples - chernozems developed on loess - from the near vicinity of NPP Jaslovské Bohunice the exchangeable strontium fraction reached as much as 50 – 60 %.

Fat content in fermented milk beverages: determination by the Gerber method

Fermented milk beverage is a product containing milk, whey and/or other ingredients, fermented by specific microorganisms and/or added with fermented milks. Fat determination in this product is important to quality control and inspection. The Gerber method is used worldwide as a simple and rapid method for fat content analysis in raw and processed milks. In Brazil, Roese-Gottlieb is the official method for analysis of fat content in milk beverages. However, the use of Gerber method for fat content determination in fermented milk beverages is widespread throughout the industry in the country. Several authors have tested the use of Gerber method for some dairy products, but there is no report on this evaluation for fermented milk beverages. In this context, the objectives of this work were to determine the fat content of fermented milk beverages by the Gerber method and evaluate the performance of this test, using Roese-Gottlieb as a reference method. Thirty samples of fermented milk beverages were analyzed by both methods. The fat contents ranged from 1.25 to 2.40% by the Gerber method and from 1.24 to 2.50% by the Roese-Gottlieb method. There was no difference (p > 0.05) between the methods. The Gerber method can be used to determine the fat content of fermented milk beverages, without prejudice to the results obtained.

Evaluation of an ultra-rapid antibiotic susceptibility testing method on positive blood cultures with Escherichia coli

Blood stream infection (BSI) is related to high mortality and morbidity. Early antimicrobial therapy is crucial in treating patients with BSI. The most common Gram-negative bacteria causing BSI is Escherichia coli. Targeted effective treatment of patients with BSI is only possible if it is based on antibiotic susceptibility testing (AST) data after blood culture positivity. However, there are very few methods available for rapid phenotypic AST and the fastest method takes 4 h. Here we analyzed the performance of a 30 min ultra-rapid method for AST of E. coli directly from positive blood cultures (BC). In total, 51 positive BC with E. coli were studied, and we evaluated the ultra-rapid method directly on positive BC as well as on E. coli colonies cultured on agar plates. The results obtained by the new method were compared with disk diffusion. The method provided accurate AST result in 30 min to Ciprofloxacin and Gentamicin for 92% and 84% of the positive BC samples, respectively. For E. coli isolates retrieved from agar plates, 86% and 96% of the AST results were accurate for Ciprofloxacin and Gentamicin, respectively, after 30 min of assay time. When time to result was modulated in-silico from 30 to 60 minutes for the agar plate samples, accuracy of AST results went up to 92% for Ciprofloxacin and to 100% for Gentamicin. The present study shows that the method is reliable and delivers ultra-rapid AST data in 30 minutes directly from positive BC and as well as from agar plates.

A rapid method for sex identification in Cannabis sativa using High Resolution Melt (HRM) analysis.

We report the identification of two SNPs in Cannabis sativa that are associated with female and male plant sex phenotypes, and are located on the top arm of the X chromosome. High Resolution Melt analysis was used to develop and validate a novel, rapid method for sex identification in medical/recreational cannabis as well as in hemp. This method can distinguish between dioecious male (XY) and dioecious female (XX) cannabis plants with 100% accuracy, and can also be used to differentiate between male and female Humulus lupulus (hop) plants.