Toxic cyanobacterial blooms are a rich source of metabolites having a variety of biological activities. Two main groups of cyclic peptides, depsipeptides and ureido linkage-containing peptides, reportedly inhibit serine peptidases. We characterised their inhibitory properties against selected peptidases and investigated their influence on cell viability. The depsipeptide planktopeptin BL1125 is a strong linear competitive tight-binding inhibitor of leukocyte (K(i)=2.9 nm) and pancreatic (K(i)=7.2 nm) elastase and also of chymotrypsin (K(i)=6.1 nm). Anabaenopeptins B and F show no inhibition against chymotrypsin, but inhibit both elastases. The tested cyclic peptides do not inhibit trypsin, urokinase, kallikrein 1 or cysteine peptidases. All three tested cyanopeptides show no short-term cytotoxicity in concentrations of up to 10 mum, but impair the metabolic activity of normal human astrocytes after prolonged exposure (48-96 h), whereas glioblastoma cells, tumour cells of the same type, are resistant. Strong inhibition and relative selectivity of the tested cyanopeptides suggests that they are potential candidates for application in inflammatory diseases and possibly some types of cancers.

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Raising awareness on a certain topic or issue is vastly alleviated with a proliferation of the electronic media and consequently, fast information delivery. The experience shows, that this is the best and most compelling way to educate the general public. Within this paper we show how two student projects, employing various activities to raise awareness, influenced general public. We also present the benefits and negative effects of the campaigns and how they can be linked together to an interesting and educational real case scenario. Public knowledge on greening and its benefits, related to the climate changes were studied in Slovenia, with the emphasis on Savinja statistical region. We used surveys, pilot cases, organized public events and remote collaboration tools within this study. We observed lack of knowledge and experience with greening principles among general public. However, good communication skills, networking and attractive sustainable solutions have led to an increase of greening awareness. Our case study gives examples on possible approaches in the frame of climate changes prevention and is encouraging future student projects. We summarized solutions and developed appropriate tools to implement them in order to effectively and efficiently raise public awareness on sustainable integration development and greening.

Z raziskavo vodnoekoloških razmer na območju doline Zaloka leta 2020 smo sledili predhodni terenski študiji iz leta 1978. Zajeto je bilo isto območje, ki je bilo prvotno preučeno kot potencialno območje zajema pitne vode, danes pa je vključeno v komunalno oskrbo s pitno vodo za več kot 30.000 ljudi. Na podlagi fizikalno-kemijskih kazalnikov posameznih vodnih virov in podnebno-geoloških značilnosti območja smo ohranjanje dobrega vodnoekološkega stanja preučenih vodnih virov povezali s padavinskimi in hidrogeografskimi razmerami širšega območja izvira Ljubija. Nizka vsebnost nitratov in majhna nihanja tudi ostalih parametrov kažejo na majhen vpliv človeka. The year 2020 water-ecological research followed the preliminary field study from 1978. We covered the same area of the Zaloka Valley, which was originally explored as a potential drinking water area, but today is included in municipal drinking water supply for more than 30,000 people. Based on physical-chemical indicators of individual water sources and climate-geological characteristics of the area, we associated the maintenance of good water-ecological status of the studied water sources with precipitation and hydrogeographic features of the wider area of the Ljubija karst spring. The low nitrate content and small fluctuations in other parameters describe the study area as an area with low human impact.