The Influence of Extraction Parameters on Antimicrobial Activity of Propolis Extracts.

The extraction optimization of the poplar-type propolis was performed in order to improve the isolation of flavonoids as well as the corresponding antimicrobial activity of the products obtained. The efficiency of flavonoids extraction depended upon the type of extraction media used, following the rank. 80% ethanol >40 ethanol>> water, regardless of pH value. Ultrasound assisted extraction was as efficient as the maceration procedure, offering additional benefits such as short duration time and low extraction temperature. The antimicrobial efficiency of extracts prepared with 80 and 40% ethanol against the -tested microbial stains was comparable, regardless of the extraction technique used, while aqueous extracts mainly showed scarce activity. Observed activity against the yeast Candida albicans strongly correlated with flavones and flavonols content in extracts prepared (r²=0.8217), while regression analysis showed that beside flavonoids, some other components which were successfully extracted from the crude propolis contributed to the observed antimicrobial efficiency. against Bacillus subtilis and Staphylococcus aureus.

Multiplex pyrosequencing of InDel markers for forensic DNA analysis.

The capillary electrophoresis (CE) technology is commonly used for fragment length separation of markers in forensic DNA analysis. In this study, pyrosequencing technology was used as an alternative and rapid tool for the analysis of biallelic InDel (insertion/deletion) markers for individual identification. The DNA typing is based on a subset of the InDel markers that are included in the Investigator® DIPplex Kit, which are sequenced in a multiplex pyrosequencing analysis. To facilitate the analysis of degraded DNA, the polymerase chain reaction (PCR) fragments were kept short in the primer design. Samples from individuals of Swedish origin were genotyped using the pyrosequencing strategy and analysis of the Investigator® DIPplex markers with CE. A comparison between the pyrosequencing and CE data revealed concordant results demonstrating a robust and correct genotyping by pyrosequencing. Using optimal marker combination and a directed dispensation strategy, five markers could be multiplexed and analyzed simultaneously. In this proof-of-principle study, we demonstrate that multiplex InDel pyrosequencing analysis is possible. However, further studies on degraded samples, lower DNA quantities, and mixtures will be required to fully optimize InDel analysis by pyrosequencing for forensic applications. Overall, although CE analysis is implemented in most forensic laboratories, multiplex InDel pyrosequencing offers a cost-effective alternative for some applications.