During postharvest ripening of kiwifruit [ Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa cv. Bruno] at 20 degrees C, six lipoxygenase (LOX) genes exhibited different expression patterns. AdLox1 and AdLox5 were up-regulated during ripening, and transcript accumulation was delayed by 1-methylcyclopropene (1-MCP), whereas AdLox2, AdLox3, AdLox4, and AdLox6 were down-regulated with ripening. Levels of two volatiles arising from the LOX pathway, that is, n-hexanal and (E)-2-hexenal, were highest after harvest and declined during ripening at 20 degrees C, whereas the characteristic kiwifruit esters ethyl and methyl butanoate levels increased late in the ripening process. Individual fatty acid concentrations underwent little change during ripening, with linoleic (LA) and linolenic (LeA) acids constituting about 40% of the total. Application of LA and LeA to kiwifruit flesh disks promoted LOX activity and n-hexanal and (E)-2-hexenal generation, whereas inhibitors of LOX, n-propyl gallate (n-PG) and nordihydroguariaretic acid (NDGA), caused a parallel reduction in enzyme activity and in the production of C6 aldehydes. The six LOX genes showed different sensitivities to the LOX substrates and inhibitors. The ethylene up-regulated genes AdLox1 and AdLox5 were induced by LA and LeA and inhibited by n-PG and NDGA. Of the LOX genes that were down-regulated by ethylene, only AdLox4 and AdLox6 were stimulated in response to the substrates and retarded by the inhibitors. The possible roles of the six LOX genes in kiwifruit ripening and aroma development are discussed.

[001]-Oriented α-MoO3 nanoribbons were synthesized via hydrothermal method at temperature from 120 to 200 °C and following assembled a membrane on interdigital electrodes to form sensors. The sensitivity, response speed, and recovery speed of the sensor improve with the increasing hydrothermal temperature. Among them, the sample obtained at 200 °C exhibits a room-temperature response time of 14.1 s toward 1000 ppm of H2. The nanoribbons also show good selectivity against CO, ethanol, and acetone, as well as high sensitivity to H2 with a concentration as low as 500 ppb. The hydrogen sensing behavior is dependent on the redox reaction between the H2 and chemisorbed oxygen species. Higher hydrothermal temperature creates larger specific surface area and higher Mo(5+) content, leading to increased chemisorbed oxygen species on the nanoribbon surface.

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The construction of heterojunctions has been widely applied to improve the gas sensing performance of composites composed of nanostructured metal oxides. This review summarises the recent progress on assembly methods and gas sensing behaviours of sensors based on nanostructured metal oxide heterojunctions. Various methods, including the hydrothermal method, electrospinning and chemical vapour deposition, have been successfully employed to establish metal oxide heterojunctions in the sensing materials. The sensors composed with the built nanostructured heterojunctions were found to show enhanced gas sensing performance with higher sensor responses and shorter response times to the targeted reducing or oxidising gases compare with those of the pure metal oxides. Moreover, the enhanced gas sensing mechanisms of the metal oxide-based heterojunctions to the reducing or oxidising gases are also discussed, with the main emphasis on the important role of the potential barrier on the accumulation layer.

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Aim: Proteins with legume lectin domains are known to possess a wide range of biological functions. Here, the antitumor effects of two representative legume lectins, concanavalin A (ConA) and Sophora flavescens lectin (SFL), on human breast carcinoma cells were investigated in vitro and in vivo. Methods: Human breast carcinoma MCF-7 cells and human normal mammary epithelial MCF-10A cells were examined. Cell viability was detected using WST-1 and CCK-8 assays. Cell apoptosis was analyzed with Hoechst 33258 staining. Cell cycle was investigated using flow cytometry. The expression of relevant proteins was measured using Western blotting. Breast carcinoma MCF-7 bearing nude mice were used to study the antitumor effects in vivo. The mice were injected with ConA (40 mg/kg, ip) and SFL (55 mg/kg, ip) daily for 14 d. Results: ConA and SFL inhibited the growth of MCF-7 cells in dose-and time-dependent manners (IC 50 values were 15 and 20 μg/mL, respectively). Both ConA and SFL induced apoptotic morphology in MCF-7 cells without affecting MCF-10A cells. ConA and SFL dosedependently increased the sub-G 1 proportion in MCF-7 cells, while SFL also triggered the G 2 /M phase cell cycle arrest. Both ConA and SFL dose-dependently increased the activities of caspase-3 and caspase-9 and release of cytochrome c from mitochondria into cytoplasm, up-regulated Bax and Bid, and down-regulated Bcl-2 and Bcl-X L in MCF-7 cells. ConA reduced NF-κB, ERK, and JNK levels, and increased p53 and p21 levels, while SFL caused similar changes in NF-κB, ERK, p53, and p21 levels, but did not affect JNK expression. Administration of ConA and SFL significantly decreased the subcutaneous tumor mass volume and weight in MCF-7 bearing nude mice. Conclusion: ConA and SFL exert anti-tumor actions against human breast carcinoma MCF-7 cells both in vitro and in vivo.

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H–Nb2O5 nanorod arrays with c-axis orientation were in situ synthesized by a hydrothermal process, and they exhibit a blue and cyan light emission.