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Extracellular adenosine 5′-triphosphate (ATP) is a well-known signalling molecule in plants and plays important roles during plant stress response. In the present work, the treatment of tobacco cell suspension culture with exogenous hydrogen peroxide (H2O2) caused the decreases of respiratory O2 uptake, intracellular ATP production, extracellular ATP level, and reduction of cell viability. Combining this observation with the finding that the oxidative phosphorylation uncoupler or the respiratory inhibitor not only decreased intracellular ATP production but also decreased the extracellular ATP level and cell viability, it is suggested that the decrease of extracellular ATP level and cell viability under H2O2 stress could be a result of the suppressed production of intracellular ATP. Treatment with ATP-degrading enzyme, apyrase, also caused the decreases of cell viability, respiratory O2 uptake, and intracellular ATP production. More importantly, addition of exogenous ATP alleviated the H2O2-induced decreases of cell viability, respiratory O2 uptake, and production of intracellular ATP. These results indicate that extracellular ATP could be an important effector in regulating the cell viability, respiratory O2 uptake, and intracellular ATP production of tobacco cell suspension culture under H2O2 stress.

Glycoprotein is a binding protein whose structure is mainly determined by the content of sugars and proteins and the peptide bonds to which it binds. There are many kinds of glycoproteins, and they can be classified into lectin, hormone, enzyme and immunoglobulin according to the clinical role in the medical field. Glycoproteins have a variety of biological functions and are of great significance in the medical and biological fields. In order to study the biological information related to glycoproteins, it is necessary to establish a highly sensitive and efficient analytical detection method for glycoproteins. The assay of glycoproteins includes separation and purification method, structural analysis and content determination. The commonly used methods for glycoproteins determination are mass spectrometry (MS), chromatography-mass spectrometry, surface excimer resonance, and enzyme-linked immunosorbent assay (ELISA), etc. In recent years, in the detection of glycoproteins, the research and application of sensors have gradually increased. This paper briefly summarized the analysis methods of glycoproteins and reviewed the research and application of glycoprotein biosensors based on glycosyl recognition. The glycoprotein biosensors including electrochemical sensors, optical sensors and mass sensors were introduced in detail. The future development direction of glycoprotein sensors was also prospected.

Although excess excitation energy (EEE) can damage the photosynthetic apparatus and deregulate many cellular processes, some studies have reported that EEE can be used by plants to optimize the resistance to pathogen infection. Here, we investigated whether the EEE-induced resistance to pathogen infection might be mediated by mitochondrial alternative oxidase (AOX). The present work showed that exposure of Arabidopsis (Arabidopsis thaliana) leaves to short-term excess light or treatment of Arabidopsis leaves with the electron transport inhibitor, DBMIB (2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone), restricted the growth of virulent biotrophic bacteria, Pseudomonas syringae pv tomato (Pst) DC3000. Exposure to short-term excess light or DBMIB treatment also enhanced the level of the capacity of the cyanide-resistant respiration of the infected leaves. The lack of AOX1a gene in the AtAOX1a anti-sense line attenuated the excess light- or DBMIB-induced resistance toward Pst DC3000. These results indicate that AOX may play a role in regulating the EEE-induced resistance to virulent pathogen infection.

Exposure of Arabidopsis leaves to cadmium (Cd) stress led to an increase in the level of extracellular ATP (eATP). And, Cd stress also caused significant increases in lipid peroxidation and the activities of lipoxygenase (LOX) and antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT). Treatment of Arabidopsis leaves with β,γ-methyleneadenosine 5’-triphosphate (AMP-PCP), which serves as a competitive inhibitor of eATP, dampened the Cd-induced increases of lipid peroxidation and the activities of LOX and antioxidant enzymes. Under Cd stress, the leaves of dorn 1–3 mutant showed lower levels of lipid peroxidation and activities of LOX and antioxidant enzymes compared with those of wild type plants. These results suggest that the changes in lipid peroxidation and activities of LOX and antioxidant enzymes under Cd stress could be associated with eATP.

The insecticidal activity and chemical constituents of the essential oil from Ajania fruticulosa were investigated. Twelve constituents representing 91.0% of the essential oil were identified, and the main constituents were 1,8-cineole (41.40%), (+)-camphor (32.10%), and myrtenol (8.15%). The essential oil exhibited contact toxicity against Tribolium castaneum and Liposcelis bostrychophila adults with LD50 values of 105.67 μg/adult and 89.85 μg/cm(2) , respectively. The essential oil also showed fumigant toxicity against two species of insect with LC50 values of 11.52 and 0.65 mg/l, respectively. 1,8-Cineole exhibited excellent fumigant toxicity (LC50 = 5.47 mg/l) against T. castaneum. (+)-Camphor showed obvious fumigant toxicity (LC50 = 0.43 mg/l) against L. bostrychophila. Myrtenol showed contact toxicity (LD50 = 29.40 μg/cm(2) ) and fumigant toxicity (LC50 = 0.50 mg/l) against L. bostrychophila. 1,8-Cineole and (+)-camphor showed strong insecticidal activity to some important insects, and they are main constituents of A. fruticulosa essential oil. The two compounds may be related to insecticidal activity of A. fruticulosa essential oil against T. castaneum and L. bostrychophila.

The present study reports a sensitive electro-analytical method for the simultaneous determination of dihydroxybenzene isomers by using a thiadiazole film electrode, which was readily prepared by electropolymerization of 2,5-dimercapto-1,3,4-thiadiazole on a glassy carbon electrode with cyclic voltammetry. The functionalized electrode has a distinguishable and sensitive response to dihydroxybenzene isomers. Under the optimized conditions, the linear stripping peak currents showed good linear relationships with hydroquinone, catechol and resorcinol at concentration ranges 0.50–120, 0.50–110 and 1.00–110 μmol/L, and the detection limits are 0.1, 0.1 and 0.3 μmol/L, respectively. The proposed method is applicable to the simultaneous determination of dihydroxybenzene isomers in real samples with the relative standard deviations of less than 5.7% and the recovery rates of 95.6%–106%. The constructed electrode is characterized by simple preparation, good selectivity, and high sensitivity advantages.

The chemical constituents of the essential oils extracted from Artemisia giraldii and Artemisia rubripes were analyzed by GC-MS. The bioactivities of two essential oils against Tribolium castaneum and Lasioderma serricorne were investigated. The main constituents in A. giraldii essential oil were 1,8-cineole (40.72%), camphor (22.50%), terpinen-4-ol (12.41%) and α-terpineol (4.14%). β-Farnesene (12.23%), 1,8-cineole (11.09%), β-caryophyllene (10.68%), germacrene D (10.01%), camphor (7.01%) were principal constituents in A. rubripes essential oil. The essential oil of A. giraldii possessed contact and fumigant toxicities (LD50=23.72 μg/adult and LC50=16.78 mg/l air, respectively) against T. castaneum adults. In addition, the essential oil of A. giraldii possessed contact and fumigant toxicities (LD50=8.88 μg/adult and LD50=5.41 mg/l air, respectively) against L. serricorne adults. The essential oil of A. rubripes showed contact and fumigant toxicities (LD50=16.18 μg/adult and LD50=25.10 mg/l air, respectively) against L. serricorne adults, and the very low contact and fumigant toxicities against T. castaneum. The results indicated that the essential oil of A. giraldii had the potential to be developed as insecticide for control of T. castaneum and L. serricorne.

The chemical composition of the essential oil of Etlingera yunnanensis rhizomes and its contact and repellent activities against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel) were investigated. The essential oil obtained from E. yunnanensis rhizomes with hydrodistillation was performed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be estragole (65.2%), β-caryophyllene (6.4%), 1,8-cineole (6.4%), limonene (5.2%), and α-pinene (2.4%). It was found that the essential oil of E. yunnanensis rhizomes possessed contact toxicity against T. castaneum and L. bostrychophila (LD50 = 23.33 μg/adult and LD50 = 47.38 μg/cm2, respectively). Estragole, 1,8-cineole, and limonene exhibited stronger contact toxicity (LD50 values of 20.41, 18.86, and 13.40 μg/adult, respectively) than β-caryophyllene (LD50 = 41.72 μg/adult) against T. castaneum adults. Estragole possessed stronger contact toxicity (LD50 = 30.22 µg/cm2) than β-caryophyllene, 1,8-cineole, and limonene (LD50 values of 74.11, 321.20, and 239.62 μg/adult, respectively) against L. bostrychophila adults. Repellency of the crude oil was also evaluated. The essential oil and constituents possessed strong repellent activity against T. castaneum adults. The four individual constituents showed weaker repellent activity than the essential oil against L. bostrychophila adults. The results indicated that the essential oil of E. yunnanensis rhizomes and the individual constituents had the potential to be developed as a natural insecticide and repellent for the control of T. castaneum and L. bostrychophila.