Microbial biodiversity in arable soils is affected by agricultural practices

The aim of the study was to examine the differences in microbial community structure as a result of agricultural practices. Sixteen samples of cultivated and the same number of non-cultivated soils were selected. Gel bands were identified using the GelCompar software to create the presence-absence matrix, where each band represented a bacterial operational taxonomic unit. The data were used for principal-component analysis and additionally, the Shannon-Weaver index of general diversity, Simpson index of dominance and Simpson index of diversity were calculated. Denaturing gradient gel electrophoresis profiles clearly indicated differentiation of tested samples into two clusters: cultivated and non-cultivated soils. Greater numbers of dominant operational taxonomic units (65) in non-cultivated soils were noted compared to cultivated soils (47 operational taxonomic units). This implies that there was a reduction of dominant bacterial operational taxonomic units by nearly 30% in cultivated soils. Simpson dominance index expressing the number of species weighted by their abundance amounted to 1.22 in cultivated soils, whereas a 3-fold higher value (3.38) was observed in non-cultivated soils. Land-use practices seemed to be a important factors affected on biodiversity, because more than soil type determined the clustering into groups

Obećavajuća zaštitna svojstva ektoina u ljudi i životinja

Ectoine is a compatible water molecule-binding solute (osmoprotectant) produced by several bacterial species in response to osmotic stress and unfavourable environmental conditions. This amino acid derivative can accumulate inside cells at high concentrations without interfering with natural processes and can protect the cell against radiation or osmotic stress. This brief review presents the current state of knowledge about the effects of ectoine on animals and focuses on its practical use for enzyme stabilisation, human skin protection, anti-inflammatory treatment, inhibitory effects in neurodegenerative diseases, and other therapeutic potential in human or veterinary medicine.Ektoin je kompatibilni osmolit (osmoprotektant) koji proizvodi više bakterijskih vrsta kao odgovor na osmotski stres i nepovoljne uvjete u okolišu. Ovaj se derivat aminokiseline može nakupiti i dosegnuti visoke razine u samoj stanici a da pritom ne ometa prirodne stanične procese. Usto štiti stanicu od zračenja ili osmotskoga stresa. Svrha je ovoga članka dati kratak pregled dosadašnjih spoznaja o djelovanju ektoina u životinja, s posebnim osvrtom na praktičnu primjenu ovoga osmoprotektanta u stabilizaciji enzima, zaštiti kože u ljudi, protuupalnoga liječenja, sprječavanja ili usporavanja neurodegenerativnih bolesti te u ostalim oblicima liječenja ljudi i životinja

The effect of environmental factors on total soil DNA content and dehydrogenase activity

The aim of the study was a statistical evaluation of the impact of selected soil factors − water potential (pF), total organic carbon content (TOC) and land use − on the total DNA content and dehydrogenase activity (DHA) in Mollic Gleysol. Additionally, we wanted to establish the interrelations between two of the most important biological parameters in soli: activity of intracellular dehydrogenases and total DNA content. Soil originating from the surface layer of the control site displayed higher DHA (c.a. by 57%) and DNA content (c.a. by 25%) as compared to an cultiavted meadow. Our results also indicate a significant (p <0.05) positive relationship between the soil DNA content and DHA. Importantly, intensive and systematical agricultural soil usage resulted in the reduction of its DHA and DNA content