The analysis of European lacquer : optimization of thermochemolysis temperature of natural resins

In order to optimize chromatographic analysis of European lacquer, thermochemolysis temperature was evaluated for the analysis of natural resins. Five main ingredients of lacquer were studied: sandarac, mastic, colophony, Manila copal and Congo copal. For each, five temperature programs were tested: four fixed temperatures (350, 480, 550, 650 degrees C) and one ultrafast thermal desorption (UFD), in which the temperature rises from 350 to 660 degrees C in 1 min. In total, the integrated signals of 27 molecules, partially characterizing the five resins, were monitored to compare the different methods. A compromise between detection of compounds released at low temperatures and compounds formed at high temperatures was searched. 650 degrees C is too high for both groups, 350 degrees C is best for the first, and 550 degrees C for the second. Fixed temperatures of 480 degrees C or UFD proved to be a consensus in order to detect most marker molecules. UFD was slightly better for the molecules released at low temperatures, while 480 degrees C showed best compounds formed at high temperatures

Carp louse (Argulus foliaceus) study in fishery farm

The main aim of this study is the determination the prevalence of carp louse (Argulus foliaceus) in the fishery farm, and the efficiency of emamectin benzoate in the treatment of mirror carp (Cyprinus carpio). The commercial Slice 0.2% (Merck Animal Health, Canada) was used for the fish treatment. Closed recirculation system is used for carps keeping. Naturally infected carps were divided into 3 groups and fed with a therapeutic food to which different amounts of \"Slice 0.2% with the active substance - emamectin benzoate were added. The first group of carps were fed with food, which contained 50 μg/kg of fish biomass emamectin benzoate. The second one had 5 μg / kg active substance. The third (control) group was not treated. Research showed that 50 μg/kg and 5 μg / kg of fish biomass emamectin benzoate was 100% destroyed on the fish skin surface (P<0.01). Meanwhile, the control group of carp infection 7 days after treatment decreased by only 6.5%. Identical results are monitored after 14 and 21 days. In the fishing farm X, a second part of the study was carried out on 20 ha pasture pond, which cultivated 45 tonnes of fish. The dosage of emomectin benzoate of 12.5 μg/kg of fish biomass was used for treatment. Studies revealed, that individuals with higher length and weight in the pasture pond were more infected with carp lice than smaller ones (P<0.01). It has also been shown that the treatment for fish of greater length and weight was more effective than smaller ones (P<0.05). After 7 days of treatment with a 12.5 μg / kg carp biomass active ingredient, the efficiency of the product after was 94.83%. After 14 days it reached 99.75% and after 21 - 99.92% (P<0.01). Research of emamectin benzoate residue in carp meat were also carried out with Liquid Chromatograph Shimazu (Japan) at the National Institute of Food and Veterinary Risk Assesment. After the \"Slice 0.2%\" treatment, the amount of emamectin benzoate and its degradation products in carp muscle tissue was found to be lower than can be determined using the methodology chosen. This means that the prepart concentration in the muscle did not exceed the permissible (100 μ/kg body weight) norm, and therefore the production of carp could be used without restriction 7 days after treatment