Plant secondary metabolites (PSMs) play many roles including defense against pathogens, pests, and herbivores; response to environmental stresses, and mediating organismal interactions. Similarly, plant microbiomes participate in many of the above-mentioned processes directly or indirectly by regulating plant metabolism. Studies have shown that plants can influence their microbiome by secreting various metabolites and, in turn, the microbiome may also impact the metabolome of the host plant. However, not much is known about the communications between the interacting partners to impact their phenotypic changes. In this article, we review the patterns and potential underlying mechanisms of interactions between PSMs and plant microbiomes. We describe the recent developments in analytical approaches and methods in this field. The applications of these new methods and approaches have increased our understanding of the relationships between PSMs and plant microbiomes. Though the current studies have primarily focused on model organisms, the methods and results obtained so far should help future studies of agriculturally important plants and facilitate the development of methods to manipulate PSMs–microbiome interactions with predictive outcomes for sustainable crop productions.

Chlorophyll meters are widely used to guide nitrogen (N) management by monitoring leaf N status in agricultural systems, but the effects of environmental factors and leaf characteristics on leaf N estimations are still unclear. In the present study, we estimated the relationships among SPAD readings, chlorophyll content and leaf N content per leaf area for seven species grown in multiple environments. There were similar relationships between SPAD readings and chlorophyll content per leaf area for the species groups, but the relationship between chlorophyll content and leaf N content per leaf area, and the relationship between SPAD readings and leaf N content per leaf area varied widely among the species groups. A significant impact of light-dependent chloroplast movement on SPAD readings was observed under low leaf N supplementation in both rice and soybean but not under high N supplementation. Furthermore, the allocation of leaf N to chlorophyll was strongly influenced by short-term changes in growth light. We demonstrate that the relationship between SPAD readings and leaf N content per leaf area is profoundly affected by environmental factors and leaf features of crop species, which should be accounted for when using a chlorophyll meter to guide N management in agricultural systems.

N-Nitrosodiphenylamine (NDPA) is selected as a model compound to reveal the specific adsorption and catalytic function of zeolites in the removal of carcinogenic nitrosamines from the environment. The bulky NDPA molecule is indeed adsorbed in the zeolite KA having a small aperture, by insertion of the -N-N=O group into the channel and involving a specific interaction between the nitrosamine and the zeolite. Degradation of NDPA at room temperature on zeolite is reported for the first time, revealing the potential applicability of zeolites to eliminate nitrosamines under mild conditions. The acidity of zeolite is the key factor determining its ability to degrade NDPA and, among the zeolites evaluated, Hb is the most effective catalyst with an activity much higher than that of other zeolites at ambient temperature. NJC

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Hepatitis E infection, caused by the hepatitis E virus (HEV), is an important global public health concern, with particularly high mortality in pregnant women. China is generally judged to be an HEV-endemic area, but epidemiological data for HEV among pregnant women are limited. Between June 2011 and July 2013, a case-control study was conducted to estimate the seroprevalence and potential risk factors associated with the acquisition of HEV infection by pregnant women in China. Nine-hundred and ninety pregnant women who visited hospitals for antenatal follow-up or medication in Qingdao and Weihai and 965 control subjects matched by age, gender and residence were examined for the presence of anti-HEV IgG and IgM antibodies by enzyme immunoassays. Socio-demographic and behavioral characteristics from the study subjects were obtained. The overall prevalence of anti-HEV IgG in all 1,955 samples was 20.7%. In pregnant women, 16.2% of samples were anti-HEV IgG positive whereas, in control subjects 25.3% of samples were anti-HEV IgG positive, (P < 0.01). For anti-HEV IgM detection, 62 (3.2%) of the 1,955 serum samples were positive and the seroprevalence in pregnant women and control subjects was 2.6% and 3.6%, respectively. Age, contact with cats, contact with pigs and exposure to soil were found to be associated with HEV infection. These findings demonstrated the high prevalence of HEV and the considerable potential for the transmission of HEV infection in pregnant women in China.

A series of Pd/Ph-SBA-15 catalysts with ordered mesoporous structure are designed by using the phenyl-functionalized SBA-15 (Ph-SBA-15) as supports. These catalysts exhibit higher activity and selectivity toward biphenyl than Pd/SiO 2 , Pd/MCM-41, Pd/Ph-MCM-41 and Pd/SBA-15 in a water-medium iodobenzene Ullmann coupling reaction. The promoting effects on the activity and selectivity could be mainly attributed to the high dispersion of Pd active sites, the ordered mesoporous channels and the strong surface hydrophobocity which facilitate the diffusion and/or adsorption of organic reactant molecules, especially in aqueous media. Meanwhile, the relatively large pore channels are favorable for the coupling of iodobenzene to form biphenyl, which is much bigger than the byproduct benzene resulting from the dehalogenation of iodobenzene. The Pd/Ph-SBA-15 catalyst could be separated easily from reaction products and used repetitively several times, showing the superiority over the homogeneous catalysts for industrial applications.

To investigate the effects of emergent plants on CH efflux and elucidate the key factors responsible for these effects, annual monitoring of CH emissions and methanogen community dynamics in a full-scale constructed wetland (CW) was conducted. Five emergent plants (Typha orientalis, Cyperus alternifolius, Arundo domax, Iris pseudacorus, and Thalia dealbata) commonly used in CWs were selected for investigation. The greatest CH flux (annual mean 19.4 mg m h) was observed from I. pseudacorus, while the lowest CH flux (7.1 mg m h) was observed from Thalia dealbata. The CH flux from five emergent plants showed marked seasonal variation. Total nitrogen (TN) and total phosphorous (TP) were weakly correlated with CH emissions, whereas total carbon (TC) and root biomass of plants were positively correlated with CH emissions. Quantitative real-time PCR (q-PCR) analysis indicated that the gene abundance of eubacterial 16S rRNA, particulate methane monooxygenase (pmoA) and methyl coenzyme M reductase (mcrA) significantly differed among plant species. Differences in TC, root biomass, and dissolved oxygen (DO) caused by plant species were potential factors responsible for differences in methanogens, methanotrophs, and CH emissions. Methanobacteriaceae, Methanoregulaceae, Methanomicrobiaceae, and Methanosarcinaceae were the dominant families of methanogens. The pathways of methanogenesis from the five emergent plants differed, with the main pathway being hydrogenotrophic, while both hydrogenotrophic and acetotrophic methanogens were involved in A. domax. Redundancy analysis (RDA) further indicated that emergent plant types had a profound influence on the methanogenic communities. Taken together, these results suggest emergent plant species can significantly influence CH fluxes in CW through microbial communities, biochemical pathways for methanogenesis, TC, and DO. Furthermore, plant species in CWs should be considered an important factor in evaluating greenhouse gases emission. Finally, it is necessary to effectively manage CWs vegetation to maximize their environmental benefits. Graphical abstract ᅟ.

Ligand-engineering through the insertion of thiophenes precisely modulates the photoelectronic properties of metal–organic frameworks for efficient and diastereoselective photocatalytic sulfonylation–cyclisation of activated alkenes.