Advanced Materials Research Vols. 955-959

Abstract: This work evaluated the effect of cadmium (Cd) on the physiological responses of wheat (Triticum aestivum L.). For this purpose, seedlings of wheat were cultivated under controlled conditions. The plant chlorophyll content of young leaves, biomass production, superoxide dismutase (SOD) activities and phytosiderophores (PS) release by roots were assessed. Results showed that Cd decreased the chlorophyll content of young leaves, accompanied by a significant shoot and root biomass reduction across all Cd treatments. Cadmium also inhibited PS release in wheat.

Abstract: The objective of this paper is to optimize the design and structure of an airlift-driven raceway bioreactor via the computational fluid dynamics (CFD) simulation for microalgae cultivation. The calculated results showed that the airlift-driven raceway bioreactor had maximum average velocity when setting two airlift tubes (of 350 mm in length) in the middle, furthermore adding the inducing baffle structure. Under this condition, minimum dead zone ratio was obtained, which was advantageous to the microalgae cultivaiton.

Abstract: In this paper, the interaction between human serum album (HSA) and minocycline (MNC) in physiological solution had been studied by fluorescence spectroscopy, UV spectrum and FT-IR spectroscopy. The inner filter effect was corrected. The results indicated that the fluorescence quenching of HSA was primarily due to static quenching, and thermodynamic parameters exhibited hydrogen bond and van der Waals force played the major role in stabilizing HSA-MNC complex. Through site marker competitive experiments had been assigned to possess the high-affinity binding site for MNC in subdomain IIA of HSA. Binding constant was obtained to be 1.64×10⁶L·mol^-1(298K) and 1.16×10⁴L·mol^-1(310K), the number of binding sites were both 1. The alternations of HSA secondary structure, such as α-helix and β-sheet were quantitatively calculated from FT-IR.

Abstract: The negative effects of pharmaceuticals residues in aquatic environment to organisms have been attracted more and more attention in the public. In this paper, the effects of ciprofloxacin hydrochloride on community of aquatic organisms were analyzed. The acute toxicity values (EC50/LC50) for Chlorella vulgaris, Photobacterium phosphoreum, Daphnia magna and guppy were 20.61、63.27、135.15 and 365.00 mg/L respectively. The results showed that the higher chain level of organism could lead to stronger tolerance of ciprofloxacin hydrochloride. Standardization Risk Quotient (SRQ) was proposed basing on the introduction of the normalization factor into risk models. SRQ can be directly applied to judge the risk levels for the exogenous pollutants into the environment without considering the effects of aquatic organisms from different food chains.

Abstract: The genomes of Advenella have been sequenced to date, which are important bacteria in environment. However, the genome of a single strain can only provide limited information on genetic diversity. Here, genomes of Advenella were compared by bioinformatics methods. A total of 2438 genes were shared by 3 strains of Advenella. Amino acid transport and metabolism related genes dominated the shared genes of Advenella, indicates the importance of these genes to the survival of Advenella. Genes encoding protocatechuate 3,4-dioxygenase was highly conserved in the genus Advenella. This comparative analysis presents a foundation for future understanding of the biodiversity of Advenella.

Abstract: There is an increased interest in the extraction of nucleic acids from various environmental samples, since only a minority of naturally occurring microbes can be cultured using standard techniques. Nucleic acids extraction and purification from soils are extremely challenging due to the low biomass, high organic contents and high variability of soil types. This has been regarded as one of the major difficulties that hamper the development of soil microbial ecology study. No commercial nucleic acids kits currently available are capable of preparing the DNAs without modifications. The cost can be very high for DNA extraction from extreme environmental soil samples, such as soils that have extreme high or low pHs. In this work, we developed and optimized soil DNA extraction and purification methods on different soils and compared the impact of three different DNA extraction protocols on DNA yield and purity. For the three different types of soil we used, direct extraction obtained the highest DNA recover rate, but required more cleanup steps. MoBio PowerSoil® DNA Isolation Kit yields less but do not require as many downstream cleaning steps. Both of the two methods obtained a more abundant microbial community than Meta-G-Nome^TM DNA Isolation Kit.

Abstract: The paper introduced a new idea of culturing Chlorella with combined reverse osmosis (RO) brine concentrate and primary effluent from sewage treatment plant as culture medium. This method was expected to reuse wastewater resource and lower the cost of Chlorella cultivation. The biomass of Chlorella at different temperature and different proportion of RO brine (0-90% by volume) were measured. Results showed that Chlorella had an ability to grow in RO brine blended with primary effluent. The biomass of Chlorella in 30% of RO brine blended was the most. At a low temperature of 10℃, the effect of RO brine on Chlorella biomass was obvious, high temperature (30℃) inhibited the growth of Chlorella, 20℃ was the most favorable temperature for growth.

Abstract: Under different soil salinity levels, diversity of soil microbial communities from Hetao irrigated land of Inner Mongolia was studied by phospholipid fatty acid (PLFA) analysis. The study found that PLFAs biomass in saline soil was significantly lower than those of strongly salinized soil and slight salinized soil. Microbes was bacteria-based from these soil. The bacterial PLFA loading in saline soil is significantly less than those of strongly salinized soil and slight salinized soil . Cluster analysis showed that changes had obviously taken place on soil microbial composition and quantity under different soil salinity levels.About 76.89% of variation in PLFA patterns explained by PC1(the first  principal components),and 17:1, 16:0, 18:1w9c, 18:1w9t, 18:2, 18:3w3c, 12:0 were strongly negatively correlated with PC1.However,soil salinity and pH were positively correlated with PC1.We conclude that soil salinity has  a profound affect on the microbial community structure.

Abstract: Growing demand for ecofriendly technologies promotes the interest in investigation of natural flocculants and their derivatization aimed to dewatering of colloidal stable clay suspensions in a low energy consumption and environmentally friendly way. The present work used two negatively charged polysaccharides carboxylated chitosan (CC) and sodium carboxymethyl starch (CMS-Na) as flocculants and bentonite as colloidal particles system to study the influence of their charge characteristics on flocculation efficacy. Flocculation studies between negatively charged polysaccharides and negatively charged bentonite colloidal particles were systematically investigated through standard jar test procedure and laser light scattering measurements. It was found that the investigated negatively charged polysaccharides showed high flocculation performance for bentonite suspensions at less amount anionic polysaccharides doses but obvious deteriorative performance even antiflocculation process appeared at large amount anionic polysaccharides dosage.

Abstract: Edible salt (ES) is also thought to exacerbate the symptoms of Alzheimer, however, the in vivo function of ES remains poorly understand. In this work, we investigated the phenomenon using the model of Alzheimer induced by D-gal. The behavious examination results exhibited that D-gal plus ES can weaken spatial memory function in the Morris water maze; the activities of T-SOD, GSH-Px and the CAT level in both hippocampus and cortex showed that D-gal plus ES decreased the expression of T-SOD and GSH-Px, but the expression of CAT increased, the protein expression determined in both of the hippocampus and cortex demonstrated that COX-2, iNOS, NFκ-B-p65-N proteins were significantly increased. It is possible that ES acts through several mechanisms, mediating a potential role in memory damage in mice. These results suggest that further study is necessary to evaluate the effect of salt on damage of memory and to determine the molecular mechanisms.