Structure–activity relationships of antifungal phenylpropanoid derivatives and their synergy with n-dodecanol and fluconazole

trans-Anethole (anethole) is a phenylpropanoid; with other drugs, it exhibits synergistic activity against several fungi and is expected to be used in new therapies that cause fewer patient side effects. However, the detailed substructure(s) of the molecule responsible for this synergy has not been fully elucidated. We investigated the structure–activity relationships of phenylpropanoids and related derivatives, with particular attention on the methoxy group and the double bond of the propenyl group in anethole, as well as the length of the p-alkyl chain in p-alkylanisoles. Antifungal potency was largely related to p-alkyl chain length and the methoxy group of anethole, but not to the double bond of its propenyl group. Production of reactive oxygen species also played a role in these fungicidal activities. Inhibition of drug efflux was associated with the length of the p-alkyl chain and the double bond of the propenyl group in anethole, but not with the methoxy group. Although a desirable synergy was observed between n-dodecanol and anethole or p-alkylanisoles with a length of C2–C6 in alkyl chains, it cannot be explained away as being solely due to the inhibition of drug efflux. Similar results were obtained when phenylpropanoid derivatives were combined with fluconazole against Candida albicans.     

The Influence of Enzymatic Removal of Chlorpyrifos from Feed Grain Mixes on Biochemical Parameters of Rat Blood

Organophosphorus pesticides (OP) are used to protect crops from pests. Treatment of plants and animals with pesticides can be done during their growth or creation of conditions required for the long-shelf life of the agricultural products. Currently, many remedies exist for prevention and removal of intoxication consequences developed in living organisms exposed to OPs. The development of biologics for degradation of OPs and biotechnologies for their application in agriculture still represents an important task. New biologics based on stabilized forms of such enzyme as hexahistidine-tagged organophosphorus hydrolase (His₆-OPH) have been in the form of nano-sized particles for OPs detoxification. They represent enzyme-polyelectrolyte complexes (EPC) obtained by mixing solutions of His₆-OPH and polyanion under certain conditions. The main purpose of this work was to evaluate the usage efficiency of EPC based on His₆-OPH and polyglutamic acid for OPs detoxification by analyzing biochemical blood parameters of rats fed with a grain mix containing chlorpyrifos. The experiment was conducted using female Sprague-Dowly albino rats. Treatment of the feeding grain mix initially containing chlopyrifos (48 mg/kg of the mix) with EPC based on His₆-OPH (1000 U/kg of the mix) for 24 h was the most effective. The results showed that acetyl cholinesterase activity in blood of rats from the group consuming food after the enzymatic removal of chlorpyrifos, was comparable to acetyl cholinesterase activity in blood of rats consuming pure food.     

Role of infrastructure and other environmental factors affecting the distribution of alien plants in the Tatra Mts

Alien plants, although usually rare in mountain habitats, can significantly impact native species diversity. The aim of this study was to analyse patterns of alien plant distribution in the Tatra Mts (Slovakia), focusing primarily on comparison of various transportation routes as a conduit for the spread of alien plants. We collected data on transects along: (i) railways, (ii) paved roads with unlimited access, (iii) tourist routes in mountain valleys (paved and unpaved roads, footpaths) with limited access and (iv) plots in areas surrounding mountain chalets. The majority of alien plants were found in locations at lower elevations and with intensive human activity. Patterns of distribution along the main corridors in the Tatras reflect the intensity and manner of use of each transportation route. Paved roads with unlimited access and railways are used most frequently and host the greatest number of alien species. Our observations show that the mode of access of these routes is more important than the road surface. Roads with limited vehicular access, be it unpaved and paved, are very similar in their alien species richness, while paved roads with limited and unlimited access significantly differ. Footpaths that cannot be accessed by vehicles are almost free of alien plants, even though they are found in the widest elevation range and often parallel to roads in the same valley. Other factors significantly negatively affiliated with alien species richness were elevation, cover of the tree and moss layer and moisture, and positively affiliated with the amount of nutrients.     

Significance of the variation in isozymes of liver lactate dehydrogenase with thermal acclimation in goldfish--I. Thermostability and temperature dependency.

1. Total and isozyme properties as well as isozyme pattern were examined in liver lactate dehydrogenase (LDH) from goldfish acclimated to different temperatures. 2. LDH of warm-acclimated fish were thermostable and exhibited higher Q10 in low temperature range as compared with that of co ld-acclimated fish. 3. The relative activities of LDH-1, LDH-2 and LDH-3, which were more thermostable, increased and LDH-4 and LDH-5, which were more heat sensitive, decreased during warm acclimation. Q10 in the low temperature range for LDH-5 was lower than that for LDH-1.