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Compounds of pentachlorophenol and particularly the sodium salt (Na-PCP), have been widely used for a variety of agricultural and industrial purposes. The pollution of aquatic ecosystems by Na-PCP has assumed serious proportions due to its toxicity and accumulative effect in organisms and environment. The objective of this laboratory study was to examine and quantify the histopathological effects of Na-PCP on the structure of the gill, as one of the most important organs targeted by phenol entries, in the freshwater snail, Holandriana holandrii. Based on the results of a preliminary mortality test, three experimental concentrations were chosen: 0.56, 1.00 and 5.6 mg L-1 Na-PCP for the semi-static test. Histological sections, stained with hematoxylin and eosin, were observed under a light microscope equipped with digital camera and analysed with image analysis software to quantify histopathological lesions. Results indicated serious structural changes in epithelial cells and underlaying connective tissue of gills, which were accelerated with an increase of Na-PCP concentrations and more pronounced in relation to the exposed period. Significant gill structural changes appeared as a progressive necrosis at epithelial cells and the epithelial lining was interrupted, while connective tissue exhibited vacuolization, formation of large irregular spaces and damaged chitinous rods. Epithelial height measured showed significant difference among experimental groups exposed to different concentrations of Na-PCP and control. Further on, measured connective tissue width also showed a statistically significant difference. We can conclude that the histomorphometric approach in quantifying of toxicant effects on animal tissue could be applied in legislative prevention of adverse effects in freshwater ecosystems, and H. holandrii can serve as a good indicator of freshwater deterioration.

The pollution of aquatic ecosystems by sodium pentachlorophenolate (Na-PCP) has assumed serious proportions due to their toxicity and accumulative effect in organisms and environment. The objective of this experimental study was to examine and quantify the histopatological effects of Na-PCP on the structure of hepatopancreas and gill, as two most important organs targeted by phenol entries, in the freshwater snail, Holandriana holandrii. Results indicate serious structural changes in tissue and epithelial cells of both organs and were accelerated with increase of Na-PCP concentrations and more pronounced related to exposed period. In hepatopancreas, tubular lumen, vacuole surface and number per tubule, exudate area in the tubular lumen, all increased with increase in concentration. Opposite trend of decreased height was observed for digestive and basophil cells. Significant gill structural changes appeared as a progressive necrosis at epithelial cells and the epithelial lining was interrupted, while connective tissue exhibited vacuolization, formation of large irregular spaces and damaged chitinous rods. Histomorphometrical approach in quantification of toxicant effects on the organism tissue could be used in legislative prevention of hazardous effects in freshwater ecosystems and H. holandrii may serve as a reliable and sentinel indicator of freshwater deterioration.

Obična planika (Arbutus unedo L.) zimzelena je grmolika biljka iz porodice vrijesova, koja se zahvaljujući antimikrobnim i antioksidacijskim svojstvima svih svojih dijelova koristi kao sastojak tradicionalnih ljekovitih pripravaka. Najvaţniji biološki aktivni spojevi koje nalazimo u listu obične planike su polifenoli, od kojih je najzastupljeniji arbutin. UtvrĎen je antioksidativni učinak arbutina te njegova antikancerogena i protuupalna aktivnost. Biološki učinci arbutina dolaze od njegova metabolita hidrokinona. Ovo istraţivanje provedeno je s ciljem procjene učinka toksičnosti vodenog ektrakta listova obične planike i arbutina u dozama od 0,4 mg/mL; 0,2 mg/mL i 0,0114 mg/mL te hidrokinona u dozama od 0,28 mg/mL; 0,14 mg/mL i 0,008 mg/mL na stanice PK-15 i HepG2 u in vitro uvjetima. Test vijabilnosti stanica pokazao je da hidrokinon izaziva inhibiciju proliferacije stanica, dok vodeni ekstrakt listova obične planike i arbutina nisu pokazali negativan učinak. Pri većim koncentracijama hidrokinon oštećuje molekule DNA. Rezultati testa bojenja EtBr/AO ukazuju da stanice tretirane hidrokinonom ulaze u apaptozu i nekrozu u većoj mjeri od onih tretiranih vodenim ekstraktom listova obične planike i arbutinom. Na temelju navedenih rezultata moţemo zaključiti da ekstrakt listova obične planike i arbutin imaju niski toksični potencijal, dok hidrokinon u većim koncentracijama oštećuje stanice. Strawberry tree (Arbutus unedo L) is an evergreen wild shrub or a small tree in Ericacae family, which is widely used as an ingredient in the traditional medicine due to its antimicrobial and antioxidant properties. The most important biologically active compounds found in the leaf of the strawberry tree are polyphenols, among which the most common is arbutin. Its antioxidant, anticarcinogenic and anti-inflammatory properties have been confirmed. The effects of arbutin derive from hydroquinone, its metabolite. The aim of this study was to estimate the impact that the toxicity of the strawberry-tree leaf aqueous extract and arbutin in doses of 0,4 mg/mL; 0,2 mg/mL and 0,0114 mg/mL, and of hydroquinone in doses of 0,28 mg/mL; 0,14 mg/mL and 0,008 mg/mL, has on PK-15 and HepG2 cells under in vitro condition. Hydroquinone has induced cell proliferation inhibition, while the aqueous extract of the strawberry-tree leaf and arbutin have not shown the negative effects measured by cell viability test. Higher concentrations of hydroquinone have damaged the structure of the cells’ DNA moleculesThe results of the EtBr/AO staining test have shown that cells treated with hydroquinone entered into apoptosis and necrosis to a greater extent than those treated with the strawberry-tree leaf aqueous extract and arbutin. Based on these latter results, it can be concluded that the extract of the strawberry-tree leaf aqueous extract and arbutin have low genotoxic potential, while higher concentrations of hydroquinone damage the cells.

Istraženi su produkti reakcija niklovih(II) i kobaltovih(II) soli (sulfati i nitrati) s N-alkilnim derivatima iminodiacetamida (Rimda), RN(CH2CONH2)2 (Meimda, Etimda, n-Primda, i-Primda, n-Buimda, i-Buimda, t-Buimda ; Me = metil, Et = etil, n-Pr = propil, i-Pr = izopropil, n-Bu = butil ; i-Bu = izobutil ; t-Bu = tert-butil) u vodenoj otopini u stehiometrijskom omjeru 1 : 2. Niklov(II) i kobaltov(II) nitrat sa svim navedenim ligandima daju komplekse formule [M(Rimda)2](NO3)2 (M = Ni ili Co) poput [Co(n-Primda)2](NO3)2 čija je struktura prikazana na slici 1a. Analogne reakcije niklova(II) odnosno kobaltova(II) sulfata ovise o strukturi nekoordinirajuće skupine R te se kompleksi u velikom broju slučajeva ne mogu izolirati u čvrstom stanju ili se raspadaju nedugo nakon izolacije. Jedan od stabilnih kompleksa ove vrste je [Ni(n-Primda)2]SO4 ∙ 2H2O (slika 1b).