Cleanup of industrial effluents containing heavy metals : a new opportunity of valorising the biomass produced by brewing industry

Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the auto-aggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed

Bioremediation potential of Cd by transgenic yeast expressing a metallothionein gene from Populus trichocarpa

Cadmium (Cd) is an extremely toxic environmental pollutant with high mobility in soils, which can contaminate groundwater, increasing its risk of entering the food chain. Yeast biosorption can be a low-cost and effective method for removing Cd from contaminated aqueous solutions. We transformed wild-type Saccharomyces cerevisiae (WT) with two versions of a Populus trichocarpa gene (PtMT2b) coding for a metallothionein: one with the original sequence (PtMT2b ‘C’) and the other with a mutated sequence, with an amino acid substitution (C3Y, named here: PtMT2b ‘Y’). WT and both transformed yeasts were grown under Cd stress, in agar (0; 10; 20; 50 µM Cd) and liquid medium (0; 10; 20 µM Cd). Yeast growth was assessed visually and by spectrometry OD600. Cd removal from contaminated media and intracellular accumulation were also quantified. PtMT2b ‘Y’ was also inserted into mutant strains: fet3fet4, zrt1zrt2 and smf1, and grown under Fe-, Zn- and Mn-deficient media, respectively. Yeast strains had similar growth under 0 µM, but differed under 20 µM Cd, the order of tolerance was: WT < PtMT2b ‘C’ < PtMT2b ‘Y’, the latter presenting 37% higher growth than the strain with PtMT2b ‘C’. It also extracted ~80% of the Cd in solution, and had higher intracellular Cd than WT. Mutant yeasts carrying PtMT2b ‘Y’ had slightly higher growth in Mn- and Fe-deficient media than their non-transgenic counterparts, suggesting the transgenic protein may chelate these metals. S. cerevisiae carrying the altered poplar gene offers potential for bioremediation of Cd from wastewaters or other contaminated liquids

Molecular phylogenetic among saffron (Crocus sakus L.) accessions from Iran, Spain and Turkey by SSR marker

WOS: 000393732100005Saffron (Crocus sativus L.), considered the most expensive spice in the world, have been used both as a spice and as a drug ever since ancient time. This study aimed to access genetic diversity of 196 individuals representing zo saffron accessions collected from different regions of Iran, Spain and Turkey. Twenty saffron accessions were collected from most ancient cultivation areas in Iran, Spain and Turkey and DNA was extracted and twenty two different primer combinations were used for analyzing genetic diversity. Amplified products were manually scored separately for each primer and different genetic diversity indices were calculated. Twenty two primers in simple sequence repeat marker amplified a total of 44 polymorphic bands with an average of 2.0. The genetic diversity and shannon's information index varied from 0.094 to 0.722 and 0.197 to 0.982, respectively. Average of polymorphism information content and genetic distance values were 0.402 and 0.291, respectively. Cluster analysis using Neighbor -Joining method divided the accessions into four groups. Utilizing principal coordinate analysis and analysis of molecular variance, significant heterogeneity was observed among accessions. The results confirmed that the SSR marker is useful for evaluation of genetic diversity among saffron accessions. Low genetic distance (average: 0.29) and low private bands (14%) among saffron accessions from different geographical regions (Iran, Spain and Turkey) could show the existence of narrow genetic background of saffron, as a result of vegetative propagation and human selection of superior genotypes.EBILTEM institute of EGE University, Izmir TurkeyThis research was supported by EBILTEM institute of EGE University, Izmir Turkey. We appreciate the excellent technical cooperation from Ms. Betul, Duygo, Tala and Tugch

Effects of Iron, Zinc and Manganese and Method of Their Application on Phonology, Yield and Grain Quality of Sweet Corn

In order to evaluate effects of iron, zinc and manganese, and the methods of applying them on yield and yield components of sweet corn, an experiment was performed as factorial based on randomized complete block design with four replications at the Research Farm of Urmia University, during 2009-2010. Experimental factors were micronutrient fertilizers with four levels (control, iron, zinc and manganese) and micronutrient applying method with two levels (foliar and soil application). Results indicated that Interaction between experimental factors on plant height, ear diameter, grain size, 1000-grain weight, biological yield and protein percentage was significant. In most of these traits foliar application of Fe and Zn showed better results than foliar application of Mn. Also, by influenced of micronutrients applying method, foliar application was caused 13.25%, 5.38% and 24.84% increasing in numbers of grain per ear, grain yield and soluble sugar percentage. In additional soluble sugar percentage was influenced significantly by application of micronutrient elements. Based on the results, foliar application of micronutrient elements showed better results than soil application of them

Identification of markers associated with traits for use in marker-assisted selection in saffron

Odredivanje veze izmedu molekularnih markera i agronomskih osobina predstavlja odlican alat za selekciju pomo u markera. U ovoj studiji, multivarijantna stepenasta regresiona analiza korišcena je za procenu veze izmedu SSR markera i nekih agronomskih osobina u ekotipovima šafrana. a analize asocijacija koriš ene su dvogodišnje prosecne vrednosti za izmerene osobine. Rezultati postupne analize regresije otkrili su znacajnu asocijaciju izmedu osobina i proucavanih lokusa. Identifikovano je ukupno 25 SSR markera. Markeri SCA382, SCA15 i SCD219 bili su povezani sa ve inom osobina, i mogu se koristiti kao kandidat markeri u selekciji pomo u molekularnih markera. © 2018, Serbian Genetics Society.Determination of association between molecular markers and agronomic traits provides an excellent tool for marker-assisted selection. In this study, multivariate stepwise regression analysis was used to estimate associations between SSR markers and some agronomic traits in saffron ecotypes. Two-year average values for the measured traits were used for association analyses. The results of stepwise regression analysis revealed significant associations between the traits and some of the studied loci. More than one informative marker was detected for most of the traits. Totally 25 informative SSR markers were identified in two years. Markers SCA382, SCA15 and SCD219 were associated with most traits under both years. These markers are considered to be relatively more reliable. Among the SSR primers, special attention should be drawn to primers SCA382, SCA15, and SCD219, which had the highest associated fragments with most traits in two years and could be considered for use as candidate markers in marker-assisted selection. © 2018, Serbian Genetics Society

Foliar Applications of ZnO and Its Nanoparticles Increase Safflower (<i>Carthamus tinctorius</i> L.) Growth and Yield under Water Stress

Foliar application or minerals is a methodology to promote growth and/or yield and to protect plants against different kinds of stresses. Currently there is a great interest in evaluating the effect of nanoparticles for enhancing the effect of these treatments. This study was performed to evaluate and compare the effect of foliar application of zinc oxide (ZnO) and zinc oxide nanoparticles (ZnO-NPs) on the growth and yield of safflower under different irrigation regimes. Foliar applications of ZnO in all concentrations (4, 6, 8, 10, 12, and 14 g L−1) led to an increase in biomass yield, number of capitula per plant, number of seeds per capitulum, and grain yield of plants compared with control plants. The maximum increase in the studied traits was obtained with a ZnO concentration of 6, 8, and 10 g L−1. In a second round of experiments, we observed the effect of nanoparticles and found that spraying with ZnO and ZnO-NPs at a concentration of 10 g L−1 may ameliorate the deleterious effects of water deficit. The results of the present study support the idea that foliar application of ZnO improves safflower yield, especially under drought stress, and showed that using of nanoparticles increases the efficiency of the application