No abstract

The analytical method based on the HPLC coupled with UV detection (HPLC-UV) for the determination of selected antioxidants (i.e. esculetin, scopoletin, 7-hydroxycoumarine, rutin, xanthotoxin, 5-methoxypsoralen and quercetin) in plant material was developed. Two ultrasonic extraction methods for the isolation of these compounds from the plants such as Mentha longifolia L., Mentha spicata L., Ruta graveolens L., Achyllea millefolium L., Plantago lanceolata L. and Coriandrum sativum L. were used. Both of these methods, i.e. ultrasonic probe and ultrasonic bath, were optimised and compared to each other. For the proposed HPLC-UV method LOQ values in the range from 22.7 (xanthotoxin) up to 97.2 ng/mL (rutin) were obtained. For all extracts the antioxidant capacity based on the reduction of free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical was also determined. Obtained results ranged from 10.11 up to 73.50% of DPPH radical inhibition.

Abstract:The analytical method based on the high-per formance liquid chromatography coupled with UV detection (HPLC/ UV) for determination of selected antioxidants (i.e., esculetin, scopoletin, 7-hydroxycoumarine, r utin, xanthotoxin, 5-methoxypsoralen and quercetin) in plant material was developed. Pressurised fluid extraction (PFE) and ultrasonic extraction (USE) methods for the isolation of these compounds from ten real plant samples were used. Both extraction methods were optimised and compared to each other. For the proposed HPLC/UV method the LOQ values (limit of quantification) in the range from 22.7 (xanthotoxin) to 97.2 ng mL -1 (r utin) were obtained. For all extracts the antioxidant capacity based on the reduction of free 2,2-diphenyl-1-picr ylhydrazyl radical (DPPH) was also determined. Results ranged from 82.04 to 94.43% of DPPH radical inhibition for PFE method and from 76.01 to 89.94% in the case of USE method.

(2016). Highly water-soluble cyclopentadienyl and indenyl molybdenum(II) complexes -second generation of molybdenum-based cytotoxic agents. European Journal of Inorganic Chemistry, 2016Chemistry, (4), 519-529. doi:10.1002 This article may be used for non-commercial purposes in accordance With Wiley-VCH Terms and Conditions for self-archiving". Ondřej Mrózek, [a] Lucie Šebestová, [b] Jaromír Vinklárek,* [a] Martina Řezáčová, [c] Aleš Eisner, [b] Zdeňka Růžičková, [a] and Jan Honzíček [d] Abstract [BF4]2 were determined by the X-ray crystallography. All synthesized compounds exhibit increased activity against human leukemia cell lines MOLT-4 and HL-60. They are about one order of magnitude more active than cisplatin. This study has proven that modification of the outer coordination sphere of molybdenum complexes has a strong impact on their activity and may be successfully used for a design of novel highly cytotoxic active species.

Propellants consisting of nitrocellulose (NC) and/or other nitrate esters are inherently chemically unstable and undergo decomposition even under standard storage conditions. Decomposition of such compounds can be inhibited or nearly stopped when stabilizers are used. However, conventional stabilizers form nitrosamines that have toxic and carcinogenic effects. As a result, these conventional stabilizers should be replaced as soon as possible. A series of NC‐based propellants doped with different novel manufactured stabilizers were investigated using microcalorimetry, conventional stability tests, and sensitivity tests. The results were compared with propellants containing the conventional stabilizer Akardite II. The chemical structure of these new stabilizers and their decomposition products do not enable the formation of toxic N‐nitrosamines.