Development and characterization of microsatellite loci for the endemic Thalictrum smithii (Ranunculaceae).

PREMISE OF THE STUDY: Microsatellite primers were developed for the gynodioecious Chinese endemic Thalictrum smithii (Ranunculaceae). METHODS AND RESULTS: Thirty-nine microsatellite primers were developed using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) method. Thirteen microsatellite loci were found to be highly polymorphic after screening 114 specimens (60 hermaphrodite and 54 female) from three T. smithii populations. The number of alleles per locus ranged from three to 13, and the levels of observed and expected heterozygosity per locus ranged from 0.000 to 1.000 and from 0.204 to 0.834, respectively. Twenty-six of these primers were polymorphic in T. petaloideum and T. finetii. CONCLUSIONS: These markers will be useful for examining genetic diversity, polyploidy, and mating system in populations of T. smithii and for guiding study on the evolution of speciation in Thalictrum.

Isolation and identification of Penicillium chrysogenum strain Y5 and its copper extraction characterization from waste printed circuit boards.

Biohydrometallurgy is generally considered as a green technology for the recycling of industrial solid waste. In this study, an indigenous fungal strain named Y5 with the ability of high-yielding organic acids was isolated and applied in bioleaching of waste printed circuit boards (PCBs). The strain Y5 was identified as Penicillium chrysogenum by morphological and molecular identification. Meanwhile, we investigated that an optimal set of culturing conditions for the fungal growth and acids secretion was 15 g/L glucose with initial pH 5.0, temperature 25°C and shaking speed 120 rpm in shaken flasks culture. Moreover, three bioleaching processes such as one-step, two-step and spent medium processes were conducted to extract copper from waste PCBs. Spent medium bioleaching showed higher copper extraction percentage and it was 47% under 5%(w/v) pulp density. Transmission electron microscope (TEM) observation combining with energy dispersive analysis of X-rays (EDAX) showed that the leached metal ions did not obviously damage the hypha cells. All above results indicated that P.chrysogenum strain Y5 has the tolerance to metal ions, suggesting its potential in recycling of metals from waste PCBs in industry.

[Microbial Communities in Soils of Qingshuitang Industrial District in Zhuzhou].

To study the effect of heavy metal pollution on microbial communities, microbial diversity and community structure of soils near Qingshuitang industrial district in Zhuzhou, China, were analyzed by Illumina high-throughput sequencing technology. In this study, the microbial diversity and community relative abundance decreased with increased heavy metal pollution level. Proteobacteria (49.56%) were the most abundant phylum in all samples, followed by Chloroflexi (13.07%) and Acidobacteria (8.77%). The microbial community structures of all samples were similar. The overlap of OTUs was 52.64%, and the structures of the abundant OTUs subcommunities were more similar than the rare OTUs community structures were. Heavy metals caused increases in Proteobacteria and Chloroflexi and decreases in Acidobacteria and Nitrospirae. According to Spearman's correlation, Proteobacteria was significantly negatively correlated with Cr, whereas Chloroflexi was positively correlated with Cr. Cd, Cu, Pb, and Zn were significantly negatively correlated with Nitrospirae. These results showed that heavy metal pollution is an important factor affecting the soil microbial structure in the soil of the Qingshuitang industrial district.

Recycling of metals from pretreated waste printed circuit boards effectively in stirred tank reactor by a moderately thermophilic culture.

To seek a feasible technique for processing waste printed circuit boards (PCBs), pretreatment of PCBs by table separation and further bioleached by moderate thermophiles in a stirred tank reactor were investigated. The shaking table separation, conducted after grinding and sieving of PCBs, produced two fractions: metal-rich parts (RPCBs), which is more suitable for pyrometallurgy process than untreated PCBs, and metal-poor parts (PPCBs) with only 8.83% metals was then bioleached by a mixed culture of moderate thermophiles effectively. After adaptation, the mixed culture could tolerate 80 g/L PPCBs. The bioleaching results showed that metals recovery was 85.23% Zn, 76.59% Cu and 70.16% Al in only 7 days. Trace Pb and Sn were detected in the leachate because of precipitating. The microorganism community structure was analyzed by amplified ribosomal DNA restriction analysis. Two moderately thermophilic bacteria species were identified as Leptospirillum ferriphilum and Acidithiobacillus caldus. Furthermore, uncultured Thermoplasmatales archaeon was also detected in the leaching system. It was also shown that moderate thermophiles revealed best bioleaching ability when compared with mesophiles and the mixture of mesophiles and moderate thermophiles. Finally, we designed a two-stage process model according to the present study to achieve semi-industrial waste PCBs recycling and economic feasibility analysis indicated that the process was profitable.

Development and characterization of microsatellite loci for the pseudometallophyte Commelina communis (Commelinaceae).

UNLABELLED: • PREMISE OF THE STUDY: Microsatellite primers were developed for the pseudometallophyte Commelina communis (Commelinaceae), an important pioneer plant for phytoremediation of copper-contaminated soil. Two wild populations collected from metalliferous and nonmetalliferous sites were used to assess the polymorphism at each locus. • METHODS AND RESULTS: Based on the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) method, a total of 34 pairs of simple sequence repeat (SSR) markers were designed. When 40 specimens from two populations were screened, 12 microsatellite loci were found to be highly polymorphic. The number of alleles per locus ranged from one to 11 and the observed and expected heterozygosity per locus ranged from 0.000 to 1.000 and from 0.195 to 0.941, respectively. • CONCLUSIONS: These markers will be useful for examining genetic diversity, population structure, and gene flow in populations of C. communis under different edaphic conditions and guiding sustainable management plans for phytoremediation.

Effective pollinators of Asian sacred lotus (Nelumbo nucifera): contemporary pollinators may not reflect the historical pollination syndrome.

BACKGROUND AND AIMS: If stabilizing selection by pollinators is a prerequisite for pollinator-mediated floral evolution, spatiotemporal variation in the pollinator assemblage may confuse the plant-pollinator interaction in a given species. Here, effective pollinators in a living fossil plant Nelumbo nucifera (Nelumbonaceae) were examined to test whether beetles are major pollinators as predicted by its pollination syndrome. METHODS: Pollinators of N. nucifera were investigated in 11 wild populations and one cultivated population, and pollination experiments were conducted to examine the pollinating role of two major pollinators (bees and beetles) in three populations. KEY RESULTS: Lotus flowers are protogynous, bowl shaped and without nectar. The fragrant flowers can be self-heating during anthesis and produce around 1 million pollen grains per flower. It was found that bees and flies were the most frequent flower visitors in wild populations, contributing on average 87.9 and 49.4 % of seed set in Mishan and Lantian, respectively. Beetles were only found in one wild population and in the cultivated population, but the pollinator exclusion experiments showed that beetles were effective pollinators of Asian sacred lotus. CONCLUSIONS: This study indicated that in their pollinating role, beetles, probable pollinators for this thermoregulating plant, had been replaced by some generalist insects in the wild. This finding implies that contemporary pollinators may not reflect the pollination syndrome.

Flower thermoregulation facilitates fertilization in Asian sacred lotus.

BACKGROUND AND AIMS: The thermoregulatory flower of the Asian sacred lotus (Nelumbo nucifera) can maintain a relatively stable temperature despite great variations in ambient temperature during anthesis. The thermoregulation has been hypothesized to offer a direct energy reward for pollinators in lotus flowers. This study aims to examine whether the stable temperature maintained in the floral chamber influences the fertilization process and seed development. METHODS: An artificial refrigeration instrument was employed to cool flowers during the fertilization process and post-fertilization period in an experimental population. The effect of temperature on post-pollination events was also examined by removing petals in two field populations. KEY RESULTS: Treatments with low floral temperature did not reduce stigma receptivity or pollen viability in undehisced anthers. Low temperature during the fertilization period significantly decreased seed set per flower but low temperature during the phase of seed development had no effect, suggesting that temperature regulation by lotus flowers facilitated fertilization success. Hand-pollination treatments in two field populations indicated that seed set of flowers with petals removed was lower than that of intact flowers in north China, where ambient temperatures are low, but not in south China, confirming that reducing the temperature of carpels did influence post-pollination events. CONCLUSIONS: The experiments suggest that floral thermoregulation in lotus could enhance female reproductive success by facilitating fertilization.

Basic fibroblast growth factor alleviates brain injury following global ischemia reperfusion in rabbits.

The aim of this study was to explore the protective effect of basic fibroblast growth factor (bFGF) on brain injury following global ischemia reperfusion and its mechanisms. Brain injury following global ischemia was induced by four vessels occlusion and systemic hypotension. Twenty-four rabbits were randomized into three groups: group A, only dissection of vessels; group B, intravenous infusion of normal saline after reperfusion for 6 h; group C, 30 microg/kg bFGF injected intravenously at the onset of reperfusion, then infused with 10 microg/(kg.h) for 6 h. Serum neuron specific enolase (NSE), S-100B, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1), interleukin-8 (IL-8) were measured before ischemia, 30 min after ischemia, 0.5, 1, 3, 6 h after reperfusion. Brain water content was determined and cerebral histopathological damages were compared. NSE and S-100B were increased 1 h after reperfusion and reached their peaks 6 h after reperfusion, but were much higher in group B than those in group C 3, 6 h after reperfusion. In groups B and C, TNF-alpha was increased after ischemia and IL-1 and IL-8 were increased significantly 0.5 h after reperfusion, then reached their peaks 6 h, 3 h, 6 h after reperfusion respectively. TNF-alpha and IL-8 at the time points of 1 h and 3 h and IL-1 at 3 h and 6 h in group C were correspondingly lower than those in group B. These indices in group A were nearly unchanged. There were less severe cerebral histopathological damages in group C compared with group B, but no difference in brain water content. It could be concluded that bFGF alleviates brain injury following global ischemia and reperfusion by down-regulating expression of inflammatory factors and inhibiting their activities.