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Cobalt oxide (Co3O4) is currently suitable in energy storage applications because of its high capacity based on the conversion reaction mechanism. However, unmodified Co3O4 suffers from distinctly inferior rate capability and poor cycling stability. On the basis of the aforementioned considerations and density functional theory (DFT) simulations, the three-dimensional hierarchical porous structure (HPS) ultrasmall Co3O4 anchored into ionic liquid (IL) modified graphene oxide (GO) has been successfully prepared (ultrasmall/Co3O4-GA-IL). The ultrasmall/Co3O4-GA-IL consists of Co3O4 co-assembled with IL modified GO to generate the HPS which can facilitate ion transfer channels through reduction of the electron and ion transportation path and transmission impedance. In addition, N-doping graphene can enhance the inherent electrical conductivity of Co3O4, which is proved by the DFT calculations. By virtue of the novel superstructure, the ultrasmall/Co3O4-GA-IL electrode demonstrates a high reversible capacity of 1,304 mAh·g−1, an enhanced high-rate capability (715 mAh·g−1 at 5 C), and a capacity retention of 98.4% even after 500 cycles at 5 C rate, which corresponds to 0.0003% capacity loss per cycle. Pouch cells based on the cathode are further fabricated and demonstrate excellent mechanical and electrochemical properties under bent and folded state, highlighting the practical application of our deliberately designed electrode in wearable electronics.

As an inhibitor of ethylene receptors, 1-methylcyclopropene (1-MCP) can delay the ripening of papaya. However, improper 1-MCP treatment will cause a rubbery texture in papaya. Understanding of the underlying mechanism is still lacking. In the present work, a comparative sRNA analysis was conducted after different 1-MCP treatments and identified a total of 213 miRNAs, of which 44 were known miRNAs and 169 were novel miRNAs in papaya. Comprehensive functional enrichment analysis indicated that plant hormone signal pathways play an important role in fruit ripening. Through the comparative analysis of sRNAs and transcriptome sequencing, a total of 11 miRNAs and 12 target genes were associated with the ethylene and auxin signaling pathways. A total of 1741 target genes of miRNAs were identified by degradome sequencing, and nine miRNAs and eight miRNAs were differentially expressed under the ethylene and auxin signaling pathways, respectively. The network regulation diagram of miRNAs and target genes during fruit ripening was drawn. The expression of 11 miRNAs and 12 target genes was verified by RT-qPCR. The target gene verification showed that cpa-miR390a and cpa-miR396 target CpARF19-like and CpERF RAP2-12-like, respectively, affecting the ethylene and auxin signaling pathways and, therefore, papaya ripening.

Brassinosteroids act by delaying fruit ripening. The effects of different concentrations of 2,4-epibrassinolide (eBL) treatments on carambola fruit ripening were investigated. The results show that treatment of 2.8 mg L–1, eBL with 10 min effectively delays ripening and maintains the quality of carambola fruit. This is achieved by retarding color changes and firmness losses while maintaining high level of soluble protein content and vitamin C, and low organic acid content. eBL-delayed senescence may be due to the inhibition of respiration rate and enhanced antioxidant system. It is noteworthy that eBL treatment markedly reduces the content of fructose-6-phosphate (6-P-F) and enhances the activity of cytochrome oxidase (CCO), and the total activity of glucose-6-phosphate dehydrogenase (G-6-PDH) and 6-phosphate gluconate dehydrogenase (6-PGDH). eBL treatment induces the IAA and GA contents but reduces that of ABA. In general, senescence retardation and quality improvement by eBL treatment may be due to the enhanced antioxidant capacity and altered respiratory pathways.

Long-term illumination of the retina with blue-light-excited phosphor-converted light-emitting diodes (LEDs) may result in decreased retinal function, even if the levels of blue light emitted are low. New low-color-temperature dual-primary-color LEDs have been developed that are composed of only two LED chips: a red chip and a yellow chip. These LEDs are expected to become a new type of healthy lighting source because they do not emit blue light, they lack phosphor, and they solve the problem of low efficiency encountered with phosphor-converted low-color-temperature LEDs. Many studies have indicated that these new low-color-temperature LEDs are likely to have therapeutic effects. However, the biological safety of these LEDs needs to be explored before the therapeutic effects are explored. Therefore, this experiment was conducted to investigate the effects of the new low-color-temperature LEDs and fluorescent white LEDs on three types of retinal cells. We observed that the viability and numbers of retinal cells decreased gradually with increasing LED color temperature. The new low-color-temperature LEDs caused less death and adverse effects on proliferation than the fluorescent white LEDs. After irradiation with high-color-temperature LEDs, the expression of Zonula Occludens-1 (ZO-1) was decreased and discontinuous in ARPE-19 cells; the stress protein hemeoxygenase-1 (HO-1) was upregulated in R28 cells; and glial fibrillary acidic protein (GFAP) and vimentin were upregulated in rMC-1 cells. We therefore conclude that the new white LEDs cause almost no damage to retinal cells and reduce the potential human health risks of chronic exposure to fluorescent white LEDs.

Pineapple (Ananas comosus (L.) Merr.) fruit ripen and soften rapidly after harvest. This study focused on examining the effect of wax application on the ripening and storage quality of the fruit. An optimized waxing treatment (65 g L−1 for 1 min) could effectively control fruit ripening by delaying fruit color change, decreasing the respiration rate and ethylene production, decreasing content of organic acids and relieving the symptoms of internal browning of pineapple fruit. Waxing enhanced the relative level of pentose phosphate pathway of respiration and affected the enzymes involved in organic acid metabolism. Waxing also reinforced the antioxidant system and enhanced the expression levels of genes related to defense, such as PGIP. These results indicated that wax treatment could effectively improve the fruit quality, mainly through the reduction of organic acid content.

An efficient Ag-catalyzed three-component reaction of amidines, ynals, and alcohols, phenols, or water has been developed. This strategy provides a wide range of substrates and represents a simple process for the preparation of different imidazole derivatives in good yields with high regioselectivities.

Introduction Present study was to evaluate whether increased arterial stiffness was associated with target organ damage in pre-hypertensive subjects. Material and methods Pre-hypertensive subjects enrolled and echocardiography was used to evaluate left ventricular hypertrophy (LVH) and the first morning urine was collected to evaluate albumin and creatinine ratio (ALB/Cr ratio). Carotid-femoral pulse wave velocity (cf-PWV) was measured. Results A total of 420 subjects were recruited and mean age was 42.6 years. Mean systolic/diastolic blood pressure (SBP/DBP) were 130 ±9 mm Hg and 85 ±4 mm Hg. The prevalence of albuminuria and left ventricular hypertrophy was 8.6 % and 11.7 %. Mean cf-PWV was 9.2 ±1.0 m/s, with arterial stiffness prevalence was 8.8%. Subjects with arterial stiffness had higher cf-PWV value (10.6 ±0.4 m/s vs. 8.7 ±0.6 m/s, p < 0.05), and ALB/Cr ratio (28.3 ±13.2 µg/mg vs. 23.1 ± 11.4 µg/mg, p < 0.05). Overall, with multivariate regression analysis, aging and arterial stiffness were significantly associated with pre-hypertension. With stepwise adjusted for potential covariates including age, male gender, fasting plasma glucose, presence of current cigarette smoking, dyslipidemia, statins and SBP, increased cf-PWV remained independently associated with left ventricular hypertrophy and albuminuria, with an increased odds of 41 % and 24 % (p < 0.05), respectively. Conclusions In pre-hypertensive subjects, arterial stiffness is independently associated with LVH and albuminuria and cf-PWV may be a useful marker to identify target organ damage in pre-hypertensive subjects.

Wine frying status is one of the most important processes in the brewing of Chinese yellow rice wine (CYW) and has a great influence on the quality and flavor of CYW. The present work determined the ethyl carbamate (EC) concentration by gas chromatography-mass spectrometry (GC-MS) and aroma compounds by headspace solid-phase microextraction GC-MS (HS-SPME-GC-MS) during wine frying status in CYW. In addition, effects of wine frying conditions on the changes of EC and aroma compounds were also investigated. Results indicated that EC concentration increased along with the increase of wine frying temperature and time. Pearson test indicated that EC had highly significant correlation (p

In the present work, fruit quality and antioxidant property of twenty-two cultivars of mulberry (Morus sp.) from China were evaluated. The results showed that contents of total soluble solid (TSS), titratable acid (TA), phenolics and anthocyanin as well as antioxidant enzyme activity and antioxidant capacity varied with cultivars. Among the twenty-two cultivars, contents of TSS and TA ranged from 6.2 to 16.00% and 0.20 to 2.05% citric acid, with Jiguihua and Mengjian 5 showing the highest level, respectively. Most of cultivars were rich in anthocyanin and phenolics, and the highest contents were detected in Zhongshen 831. Highest activities of antioxidant enzymes, including As-POD, G-POD, CAT, GR, GSH-POD and SOD were found in Taiwanguosang, Zhenzhubai, Mengjian 4, 72C002, Da 10, and Jiguihua, respectively. Moreover, principal component analysis revealed that Zhongshen 831, Huayang novel and Zhongsang 5801 exhibited higher antioxidant capacities.

Low-temperature storage is a common strategy for preserving and transporting vegetables and fruits. However, many fruits are hypersensitive to chilling injury, including bananas. In the present study, storage conditions of 11 &deg, C delayed the ripening of Fenjiao (Musa ABB Pisang Awak) banana, and the pulp could be softened after ethephon treatment. Storage conditions of 7 &deg, C prevented fruit from fully softening, and fruit contained a significantly higher starch content and lower soluble sugar content. MaEBF1, a critical gene component in the ethylene signaling pathway, was repressed during ripening after fruit had been stored for 12 days at 7 &deg, C. The expression of a series of starch degradation-related genes and a MaNAC67-like gene were also severely repressed. Both MaEBF1 and MaNAC67-like genes were ethylene-inducible and localized in the nucleus. MaNAC67-like protein was able to physically bind to the promoter of genes associated with starch degradation, including MaBAM6, MaSEX4, and MaMEX1. Yeast two-hybrid, GST-pull down, and BiFC assays showed that MaEBF1 interacted with the MaNAC67-like protein, and their interaction further activated the promoters of MaBAM6 and MaSEX4. The current study indicates that MaNAC67-like is a direct regulator of starch degradation and potential for involvement in regulating chilling-inhibited starch degradation by interacting with the ethylene signaling components in banana fruit. The present work paves the way for further functional analysis of MaEBF1 and MaNAC67-like in banana, which will be useful for understanding the regulation of banana starch metabolism and fruit ripening.

Background Ethylene promotes fruit ripening whereas 1-methylcyclopropene (1-MCP), a non-toxic antagonist of ethylene, delays fruit ripening via the inhibition of ethylene receptor. However, unsuitable 1-MCP treatment can cause fruit ripening disorders. Results In this study, we show that short-term 1-MCP treatment (400 nL•L− 1, 2 h) significantly delays papaya fruit ripening with normal ripening characteristics. However, long-term 1-MCP treatment (400 nL•L− 1, 16 h) causes a “rubbery” texture of fruit. The comparative transcriptome analysis showed that a total of 5529 genes were differently expressed during fruit ripening compared to freshly harvested fruits. Comprehensive functional enrichment analysis showed that the metabolic pathways of carbon metabolism, plant hormone signal transduction, biosynthesis of amino acids, and starch and sucrose metabolism are involved in fruit ripening. 1-MCP treatment significantly affected fruit transcript levels. A total of 3595 and 5998 differently expressed genes (DEGs) were identified between short-term 1-MCP, long-term 1-MCP treatment and the control, respectively. DEGs are mostly enriched in the similar pathway involved in fruit ripening. A large number of DEGs were also identified between long-term and short-term 1-MCP treatment, with most of the DEGs being enriched in carbon metabolism, starch and sucrose metabolism, plant hormone signal transduction, and biosynthesis of amino acids. The 1-MCP treatments accelerated the lignin accumulation and delayed cellulose degradation during fruit ripening. Considering the rubbery phenotype, we inferred that the cell wall metabolism and hormone signal pathways are closely related to papaya fruit ripening disorder. The RNA-Seq output was confirmed using RT-qPCR by 28 selected genes that were involved in cell wall metabolism and hormone signal pathways. Conclusions These results showed that long-term 1-MCP treatment severely inhibited ethylene signaling and the cell wall metabolism pathways, which may result in the failure of cell wall degradation and fruit softening. Our results reveal multiple ripening-associated events during papaya fruit ripening and provide a foundation for understanding the molecular mechanisms underlying 1-MCP treatment on fruit ripening and the regulatory networks. Electronic supplementary material The online version of this article (10.1186/s12870-019-1904-x) contains supplementary material, which is available to authorized users.

Ethylene plays a pivotal role in climacteric fruit ripening; whereas 1-MCP, a non-toxic antagonist of ethylene, prevents ethylene-dependent responses and fruit ripening. In this study, a short-term treatment (1 h) with 400 nL L−1 1-MCP delayed the ripening of harvested papaya. However, long-term application of 1-MCP (400 nL L−1, 16 h) resulted in abnormal fruit ripening, with the fruits exhibiting normal yellowing without softening, significantly higher cellulose and lignin contents, and intact cell walls (CW). Furthermore, we found that long-term treatment with 1-MCP significantly inhibited the expression of CpEBF1, an EIN3-binding F-box-1 gene. A protein interaction analysis using yeast two-hybrid, BiFC and GST pull-down assays showed that CpEBF1 interacts with the CpMADS1/3 and CpEIL1 proteins. The interaction of CpEBF1 with CpMADS1/3 further activated the activities of CW-degradation gene promoters. Subcellular localization showed that these proteins were localized in the nucleus. Additionally, the expression levels of CpMADS1/3, CpEIL1, and several CW-degradation-related genes were significantly downregulated by long-term 1-MCP treatment. Therefore, we propose that the inhibited expression of CpEBF1 and CpMADS1/3 resulted in the repressed activation of CW-degradation-related genes via their interaction, thereby resulting in fruit softening disorders., Papaya: Anti-ripening treatment prevents degradation of cell wall Long-term treatment with an anti-ripening agent inhibits the expression of regulatory genes that normally break down the cell wall of the papaya fruit. A team from Guangzhou’s South China Agricultural University led by Xueping Li and Weixin Chen applied a hormone inhibitor to papayas at the breaker stage of fruit ripening. 1 h of treatment delayed ripening, whereas 16 h of treatment caused the fruit to become rubbery, with significantly higher levels of cellulose and lignin, both structural components of the cell wall. The researchers identified two genes with reduced expression following extended hormone-blocking treatment. Both normally encode proteins that aid in degrading the cell wall to promote fruit ripening. The findings thus offer a molecular explanation for why misuse of anti-ripening agents on papaya fruits can lead to undesirable characteristics.

Papaya fruits accumulate carotenoids during fruit ripening. Although many papaya carotenoid biosynthesis pathway genes have been identified, the transcriptional regulators of these genes have not been characterized. In this study, a NAC transcription factor, designated as CpNAC1, was characterized from papaya fruit. CpNAC1 was localized exclusively in nucleus and possessed transcriptional activation activity. Expression of carotenoid biosynthesis genes phytoene desaturases (CpPDSs) and CpNAC1 was increased during fruit ripening and by propylene treatment, which correlates well with the elevated carotenoid content in papaya. The gel mobility shift assays and transient expression analyses demonstrated that CpNAC1 directly binds to the NAC binding site (NACBS) motifs in CpPDS2/4 promoters and activates them. Collectively, these data suggest that CpNAC1 may act as a positive regulator of carotenoid biosynthesis during papaya fruit ripening possibly via transcriptional activation of CpPDSs such as CpPDS2/4.

Benzothiadiazole (BTH) works as a plant activator. The effects of different BTH treatments and fungicides SPORGON on fruit ripening and disease incidence were investigated. The results showed that BTH treatment significantly delayed fruit ripening, maintained fruit firmness, color, and good fruit quality, and dramatically reduced the incidence of disease. BTH effectively inhibited the invasion and development of pathogenic bacteria and controlled the occurrence of disease. BTH treatment enhanced the activities of defense-related enzymes, including chitinase, phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase, increased the content of hydrogen peroxide and total antioxidant capacity, and reduced malondialdehyde content. Cellular structure analysis after inoculation confirmed that BTH treatment effectively maintained the cell structural integrity. SPORGON did not provide benefits for delaying fruit ripening or for the resistance system, while it can control the disease only during the earlier stage and not at later stages.

A novel one pot, metal-free, three-component domino reaction for the formation of furan derivatives has been developed from 3-phenylpropiolaldehyde, 1,3-dicarbonyl compounds and aromatic amine or aliphatic acid. This transformation provided a general and facile access to the construction of C–O and C–N bonds to prepare various bioactive furans in good yields.

1-Methylcyclopropene (1-MCP) has been widely used to manipulate fruit ripening. However, inappropriate treatment with 1-MCP may cause ripening disorders. In this study, we observed that the appropriate concentration of 1-MCP (400 nl L−1, 6 h) (1-MCP400) significantly delayed the ripening of Fenjiao banana. However, a high concentration of 1-MCP (3200 nl L−1, 6 h) (1-MCP3200) resulted in abnormal Fenjiao banana that ripened with softened fruit that had a green peel. An RNA sequencing analysis showed that a large number of differentially expressed genes (DEGs) in the fruit peel and pulp were screened out from fruit that were ripened as controls. A KEGG analysis revealed that the metabolic pathways of plant hormone signal transduction, starch and sucrose metabolism, phenylpropanoid biosynthesis, photosynthesis and biosynthesis of amino acids were significantly enriched during fruit ripening. The fruit transcript level of fruit was markedly altered by 1-MCP treatment. Large numbers of DEGs were also detected between high and appropriate concentrations of 1-MCP in the peel and pulp. A comprehensive functional enrichment analysis showed that most of the DEGs involved in photosynthesis, cysteine and methionine metabolism, phenylpropanoid biosynthesis, amino sugar and nucleotide sugar metabolism, plant hormone signal transduction, starch and sucrose metabolism were enriched. RT-qPCR verified the RNA-Seq results, which indicated that 1-MCP3200 severely repressed the expression of genes involved in ethylene (MaACS1, MaACO1, MaETR2-like, MaERF003, MaERF012 and MaERF113), auxin (MaARF19-like, MaSAUR71-like and MaSAUR72-like) and abscisic acid (MaPYL3-like and MaABI5-like) signaling pathways, chlorophyll and cell wall degradation, and starch and sucrose metabolism but induced the expression of genes in lignin synthesis. These genes were consistently expressed in the pulp and peel following control and 1-MCP400 treatment, but their expression was inconsistent following 1-MCP3200 treatment, which may result in the failure of the peel to turn yellow in the 1-MCP3200 group.

Fenjiao (Musa ABB Pisang Awak) is a popular banana cultivar due to its good taste and stress resistance, but it has a short shelf-life and deteriorates rapidly post-harvest. The effects of 1-methylcyclopropene (1-MCP) treatment on fruit physiology and quality and transcriptomic profiles are investigated in this study. The results showed that 1-MCP significantly delayed fruit ripening by repressing fruit softening and inhibiting the respiratory rate and ethylene production. The 1-MCP treatment delayed sugar accumulation and influenced the content of the precursors of the biosynthesis of aroma volatiles. 1-MCP reduced the production of flavor-contributing volatile esters isoamyl isobutyrate, isoamyl acetate and trans-2-hexenal and hexanal, but dramatically increased the hexyl acetate production at the full-ripening stage. The transcriptomic analysis showed that 1-MCP dramatically affected the transcript profiles during fruit ripening, especially the KEGG pathways involved in amino acid metabolism, biosynthesis of other secondary metabolites, carbohydrate metabolism, lipid metabolism, signal transduction, and translation classes. The key genes and the corresponding enzyme activities involved in the volatile and ethylene synthesis were severely repressed due to the 1-MCP treatment. The 1-MCP treatment effectively delayed Fenjiao fruit ripening, but affected volatile production by reducing the precursor production and expression level of genes involved in the metabolism pathways of ethylene, auxin and volatiles.

Aromatic compounds are important for fruit quality and can vary among fruit cultivars. Volatile compounds formed during the ripening of two banana cultivars, Brazilian and Fenjiao, were determined using headspace solid-phase micro-extraction (SPME) and gas chromatography coupled with mass spectrometry (GC-MS). These two cultivars exhibited different physiological characteristics during storage. Fenjiao fruit exhibited faster yellowing and softening, a higher respiration rate and greater ethylene production. Also, the soluble sugar content in Fenjiao fruit was much higher than in Brazilian fruit. In total, 62 and 59 volatile compounds were detected in Fenjiao and Brazilian fruits, respectively. The predominant volatile components isoamyl acetate, butanoic acid, 3-methyl-3-methylbutyl ester, hexanal, trans-2-hexenal and 1-hexanol varied during ripening stages. Moreover, esters were more abundant in Fenjiao, and propanoic acid 2-methylbutyl ester, and octanoic acid were only detected in Fenjiao. These compounds contribute to the unique flavors and aromas of the two cultivars.

1-methylcyclopropene (1-MCP) has obvious effects on delaying the ripening of harvested banana fruit. However, improper concentration, treatment time and handling methods could affect normal ripening, yellowing, softening and formation of volatiles, which are important components of banana fruit quality. This study was performed to screen and test the effect of a combination of low concentration ethephon with 1-MCP on the ripening of banana fruit, as well as on physiological and biochemical changes. The results showed that a combination of 50 μL L−1 ethephon with 400 nL L−1 1-MCP (16 h) was the most suitable treatment, which significantly delayed the ripening and maintained the commodity value of harvested banana fruit without detrimentally affecting normal ripening after ripening acceleration treatment. This treatment effectively delayed and decreased respiration rate and ethylene production, inhibited the activity of pectin lyase (PL), pectin methylesterase (PME), cellulase (CX) and polygalacturonase (PG), and delayed the peak activity of ACC synthase (ACS) and ACC oxidase (ACO). It also delayed the formation of volatile compounds, but did not detrimentally affect the amount of volatiles, especially the esters. The combined treatment significantly delayed the ripening and prolonged the shelf life of banana fruit with normal coloring and volatile development, which effectively maintained the commercial value of banana fruit.

Banana fruits harvested at the mature green stage were treated with 60 μL L −1 nitric oxide (NO) for 3 h at 22 °C, and then stored at 7 ± 1 °C with 90% RH for 15 days. The results showed that the application of NO at 60 μL L −1 was most effective in reducing chilling injury in banana fruit. The treatment reduced increases in electrolyte leakage and malondialdehyde content, and delayed increases in both superoxide anion (O 2 − ) production rate and H 2 O 2 content. Fruit treated with NO exhibited higher activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX), and significantly higher expression of MaSOD , MaCAT , MaPOD and MaAPX genes than control fruit during storage. These results indicate that NO treatment might enhance chilling tolerance of banana fruit via improving the activities of antioxidant enzymes and inducing the expression of antioxidant-related genes.

Objective It has been found that ulinastatin (UTI) can attenuate hepatic injury in a rat model of ischemia reperfusion (IR), but the specific mechanism is unclear. This study aims to investigate possible pathomechanism of ulinastatin in reducing the inflammatory response after hepatic IR. Methods A male sprague-dawley(SD) rat model of hepatic ischemia reperfusion injury was used. The rats were randomly divided into 4 groups on average, which were 0.9% saline and IR group as control, ulinastatin preconditioning (UPC) group, UPC+rHMGB1 (recombinant HMGB1) group and UPC +anti-HMGB1 group. Serum aminotransferases, TNF-α, IL-1 and Myeloperoxidase (MPO) levels were measured. Histopathology examination and apoptotic cell detection and the different expression of HMGB1 protein were also assessed. Results Serum levels of aminotransferases, cytokines and hepatic MPO in UPC and UPC+anti-HMGB1 groups were significantly lower than those in control group (p

Papaya fruits ( Carica papaya L. cv ‘Sui you 2’) harvested with

Keratin particles with microscale are prepared by ball mill and its influences on the chitosan membrane is evaluated. Composite membranes with various content of keratin are fabricated, and their physical and chemical properties such as morphology, wettability, crystallization, thermal stability, tensile strength, and break elongation are investigated. Optical microscope and situ topographic scan mode of nano-test system are used to examine the dispersion and aggregation of keratin on the surface of chitosan membrane. The result of contact angle (CA) and mechanical testing show that the incorporation of keratin particles decrease the CA from 98.1 ° to 58.2 °. Tensile strength and break elongation of the composite membrane reaches a maximum of 65 ± 8 MPa and 15% when the keratin content is 6%, an increase of 80% and 88% compared with the pristine chitosan membrane. Both the increase in tensile strength and break elongation is result of the incorporation of keratin particles known for their excellent compatibility between keratin and chitosan matrix. These kind of composite material combines the antibacterial properties of chitosan with cell culture preference of keratin which may have potential biomedical application. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 134, 44667.

Photoreactive and cytocompatible polymer nanoparticles for immobilizing and photoinduced releasing proteins were prepared. A water-soluble and amphiphilic phospholipid polymer, poly (2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)-co-4-(4-(1-methacryloyloxyethyl)-2-methoxy-5-nitrophenoxy) butyric acid (PL)) (PMB-PL) was synthesized. The PMB-PL underwent a cleavage reaction at the PL unit by photoirradiation at a wavelength of 365 nm. Additionally, the PMB-PL took polymer aggregate in aqueous medium and was used to modify the surface of biodegradable poly (L-lactic acid) (PLA) nanoparticle as an emulsifier. The morphology of the PMB-PL/PLA nanoparticle was spherical and approximately 130 nm in diameter. The carboxylic acid group in the PL unit could be used for immobilization of proteins by covalent bonding. The bound proteins were released by a photoinduced cleavage reaction. Within 60 sec, up to 90% of the immobilized proteins were released by photoirradiation and activity of the protein released in the medium was maintained as well as that the original proteins before immobilization. Octa-arginine (R8) could promote internalization of the protein/PLA/PMB-PL nanoparticles into cells when the R8 was co-immobilized on the nanoparticles. After that, photoirradiation induced protein release from the nanoparticles and proteins distributed more evenly inside cells. From these results, we concluded that PMB-PL/PLA nanoparticles have the potential to be used as smart carriers to deliver proteins to biological systems, such as the inside of living cells.

A novel one pot, metal-free, three-component domino reaction for the formation of furan derivatives has been developed from 3-phenylpropiolaldehyde, 1,3-dicarbonyl compounds and aromatic amine or aliphatic acid. This transformation provided a general and facile access to the construction of C–O and C–N bonds to prepare various bioactive furans in good yields.

The present study was performed to investigate the effect of nitric oxide (NO) fumigation on fruit ripening of harvested “Sui you 2” Carica papayas in relation to postharvest quality and soluble sugar content. Fruits were fumigated for 3 h with 60 μL/L NO and stored at 20C and 75% relative humidity for 20 days. NO treatment effectively suppressed ethylene formation and respiratory rate (CO2 levels), reduced weight loss, maintained firmness and delayed changes in peel color and soluble solid contents during 20 days of storage. The level of vitamin C initially increased and then declined slightly during storage at a slower rate in the NO-treated fruits than in controls. Exposure to 60 μL/L NO resulted in significant decreases in fructose and sucrose content. Glucose content in NO-treated fruits was higher than that in controls. Our results indicate that NO gas can be used to prolong fruit storage life and delay changes in soluble sugar content in papaya fruit. Practical Applications Nitric oxide (NO) gas, a highly reactive free radical, is being studied to resist vegetative stress and senescence of horticultural products. NO was initially regarded as an environmental pollutant, but since 1996, when emission of NO from plants was reported by Leshem and Haramaty, it has drawn much worldwide attention. The present study was performed to investigate the effect of NO fumigation on fruit ripening of harvested “Sui you 2” Carica papaya in relation to the postharvest quality and content of soluble sugars. Our results indicate that NO gas can be potentially applied for prolonging the storage life and delaying soluble sugar change of papaya fruit.

The plant-specific NAC (NAM, ATAF1/2, and CUC2) transcription factors (TFs) play important roles in plant growth, development, and stress responses. However, the precise role of NAC TFs in relation to fruit ripening is poorly understood. In this study, six NAC genes, designated MaNAC1–MaNAC6, were isolated and characterized from banana fruit. Subcellular localization showed that MaNAC1–MaNAC5 proteins localized preferentially to the nucleus, while MaNAC6 was distributed throughout the entire cell. A transactivation assay in yeast demonstrated that MaNAC4 and MaNAC6, as well as their C-terminal regions, possessed trans-activation activity. Gene expression profiles in fruit with four different ripening characteristics, including natural, ethylene-induced, 1-methylcyclopropene (1-MCP)-delayed, and a combination of 1-MCP with ethylene treatment, revealed that the MaNAC genes were differentially expressed in peel and pulp during post-harvest ripening. MaNAC1 and MaNAC2 were apparently upregulated by ethylene in peel and pulp, consistent with the increase in ethylene production. In contrast, MaNAC3 in peel and pulp and MaNAC5 in peel were constitutively expressed, and transcripts of MaNAC4 in peel and pulp and MaNAC6 in peel decreased, while MaNAC5 or MaNAC6 in pulp increased slightly during fruit ripening. Furthermore, the MaNAC2 promoter was activated after ethylene application, further enhancing the involvement of MaNAC2 in fruit ripening. More importantly, yeast two-hybrid and bimolecular fluorescence complementation analyses confirmed that MaNAC1/2 physically interacted with a downstream component of ethylene signalling, ethylene insensitive 3 (EIN3)-like protein, termed MaEIL5, which was downregulated during ripening. Taken together, these results suggest that MaNACs such as MaNAC1/MaNAC2, may be involved in banana fruit ripening via interaction with ethylene signalling components.

MYC2, a basic helix-loop-helix (bHLH) transcription factor, is a key regulator in the activation of jasmonate (JA) response. However, the molecular details of MYC2 involving in methyl jasmonate (MeJA)-induced chilling tolerance of fruit remain largely unclear. In the present work, two MYC2 genes, MaMYC2a and MaMYC2b, and one homolog of the inducer of the C-repeat-binding factor (CBF) gene, MaICE1 were isolated and characterized from banana fruit. MaMYC2s and MaICE1 were found to be all localized in the nucleus. In addition, the proline-rich domain (PRD) and the acidic domain (AD) in the N-terminus were important for the transcriptional activation of MaMYC2 in yeast cells. Unlike MaICE1's constitutive expression, MaMYC2a and MaMYC2b were induced rapidly following MeJA treatment during cold storage. Moreover, protein-protein interaction analysis confirmed that MaMYC2s interacted with MaICE1. The expression of ICE-CBF cold-responsive pathway genes including MaCBF1, MaCBF2, MaCOR1, MaKIN2, MaRD2 and MaRD5 was also significantly induced by MeJA. Taken together, our work provides strong evidence that MaMYC2 is involved in MeJA-induced chilling tolerance in banana fruit through physically interacting and likely functionally coordinating with MaICE1, revealing a novel mechanism for ICE1 in response to cold stress as well as during development of induced chilling tolerance.

The consumption of pu-erh tea has been increasing rapidly in recent years. Pu-erh tea is considered to be much more beneficial to human health than other kinds of tea. Antioxidant activity is the main medicinal property of pu-erh tea. The present study compared the antioxidant activities of water extracts of tea (WEOT) and sun-dried green tea with different fermentation degrees in vitro. Antioxidant capacities of the WEOTs were evaluated by testing their total antioxidation capacity. The free radical scavenging capacity was evaluated using 1-1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assays, hydroxyl radical scavenging assays and superoxide anion free radical scavenging assays. Results showed that, of all the WEOTs, the first pile-fermentation tea sample gave the strongest scavenging ability of both DPPH radical and hydroxyl radical, followed by the sun-dried green tea, and DPPH radical scavenging activity was higher than that of hydroxyl radical. DPPH scavenging ability of the sun-dried green tea, the first, the second, the third and the fourth pile-fermentation tea were 87.90%, 89.29%, 85.86%, 82.62% and 80.94%, respectively. The scavenging ability of hydroxyl free radical for the WEOTs of the first pile-fermentation tea is significantly higher (P < 0.05) when compared with other extracts, with a 26.21% inhibition. The first pile-fermentation WEOT exhibited the most potent scavenging activity of superoxide anion free radical and total antioxidation capacity, while the fourth pile-fermentation WEOT had the lowest activity. The superoxide anion free radical scavenging activity and total antioxidation capacity of WEOTs had the most significant difference (P

BACKGROUND: Little attention has been paid to characterising the ethylene-signalling pathway genes in relation to abnormal ripening of harvested banana fruit during storage at high temperature. The aim of the present study was to investigate banana fruit abnormal ripening and the expression of ten genes associated with the ethylene-signalling pathway, namely MaACS1, MaACO1, MaERS1–4 and MaEIL1–4, at high temperature. Changes in these parameters of banana fruit at high temperature in response to 1-MCP pretreatment were also investigated. RESULTS: High temperature accelerated the decline in fruit firmness, increased ethylene production and inhibited degreening in banana fruit, resulting in fruit abnormal ripening. In addition, the expression of MaACS1, MaACO1, MaERS2, MaERS3, MaERS4, MaEIL1, MaEIL3 and MaEIL4 was enhanced in banana fruit stored at high temperature. However, application of 1-MCP prior to high temperature storage delayed fruit abnormal ripening and simultaneously suppressed the expression of MaACS1, MaERS2, MaERS3, MaEIL1, MaEIL3 and MaEIL4. CONCLUSION: The findings of this study suggested that the expression of genes associated with the ethylene-signalling pathway might be involved in banana fruit abnormal ripening at high temperature. Application of 1-MCP suppressed the expression of genes associated with the ethylene-signalling pathway, which may be attributed at least partially to 1-MCP delaying fruit abnormal ripening at high temperature. Copyright © 2010 Society of Chemical Industry

Three full-length cytosol small heat shock protein (sHSP) genes, including two class I sHSP (CI sHSP) and one class II sHSP (CII sHSP) cDNAs, termed Ps-CI sHSP1 , Ps-CI sHSP2 and Ps-CII sHSP1 respectively, were isolated and characterized from plum fruit at harvest. Their expression in relation to heat shock and cold acclimation-induced chilling tolerance were investigated. Heat shock treatment by dipping the fruit in water at 55 °C hot for 2 min and cold acclimation by conditioning the fruit at 8 °C for 5 d prior to storage at 2 °C could effectively reduce malondialdehyde (MDA) content and alleviate chilling injury. Furthermore, accumulation of Ps-CII sHSP1 mRNA transcripts in the fruit during the subsequent storage at 2 °C was remarkably enhanced by heat shock and cold acclimation treatments. These data suggest that heat shock and cold acclimation treatments induced the expression of Ps-CII sHSP1 , which may be involved in chilling tolerance of the fruit caused by these treatments.

Photoreactive and cytocompatible polymer nanoparticles for immobilizing and releasing proteins were prepared. A water-soluble and amphiphilic phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)-co-4-(4-(1-methacryloyloxyethyl)-2-methoxy-5-nitrophenoxy) butyric acid (PL)) (PMB-PL) was synthesized. The PMB-PL underwent a cleavage reaction at the PL unit with photoirradiation at a wavelength of 365 nm. Additionally, the PMB-PL took polymer aggregate in aqueous medium and was used to modify the surface of biodegradable poly(L-lactic acid) (PLA) nanoparticle as an emulsifier. The morphology of the PMB-PL/PLA nanoparticle was spherical and approximately 130 nm in diameter. The carboxylic acid group in the PL unit could immobilize proteins by covalent bonding. The bound proteins were released by a photoinduced cleavage reaction. Within 60s, up to 90% of the immobilized proteins was released by photoirradiation. From these results and with an understanding of the fundamental properties of MPC polymers, we concluded that PMB-PL/PLA nanoparticles have the potential to be used as smart carriers to deliver proteins to biological systems, such as the inside of living cells.

Ethylene response factors (ERFs) play important roles in fruit development, ripening, defense responses and stress signaling pathways. After harvest, climacteric fruit such as papaya are subject to a range of problems associated with postharvest handling and storage treatments. There have been few attempts to evaluate the role of ERFs in fruit's responses to environmental stimuli. To investigate the transcriptional mechanisms underlying fruit developmental, ripening and stresses, we cloned four ERFs from papaya. The deduced amino acid sequence of CpERFs contained the conserved apetalous (AP2)/ERF domain, which shared high similarity with other reported AP2/ERF domains. The phylogeny, gene structures, and putatively conserved motifs in papaya ERF proteins were analyzed, and compared with those of Arabidopsis. Expression patterns of CpERFs were examined during fruit development, under 1-MCP treatment, ethephon treatment, biotic stress (temperature stress) and pathogen stress. CpERFs displayed differential expression patterns and expression levels under different experimental conditions. CpERF2 and CpERF3 showed a close association with fruit ripening and CpERFs had a high expression level in the earlier stages during the fruit development period. The expression of CpERFs strongly associated with stress response. These results support the role for papaya ERFs in transcriptional regulation of ripening-related or stress-respond genes and thus, in the regulation of papaya fruit-ripening processes and stress responses.

We expounded the effect of intravenous arginine on the healing of human skin graft donor sites. This randomized study was double blind and controlled by placebos from October 2012 to May 2015. Nine patients were selected into the arginine group and 10 were selected into the control group. There was no significance in age, weight, BMI, CRP, albumin and total plasma protein in arginine and control groups. Angiogenesis, re-epithelialization and neutrophil influx of wound healing were measured. The concentrations of plasma amino acid were measured to evaluate our intervention. In our study, plasma arginine and ornithine concentrations in arginine group were the highest after arginine-treated at 2 days. Supplementation of intravenous arginine could not affect on healing of human skin graft donor sites, improve angiogenesis, reepithelialization or neutrophil influx in rats.

Papaya (Carica papaya L.) is sensitive to low temperature and easy to be subjected to chilling injury, which causes fruit ripening disorder. This study aimed to investigate the relationship between the expression of genes related to ethylene and fruit ripening disorder caused by chilling injury. Papaya fruits were firstly stored at 7°C and 12°C for 25 and 30 days, respectively, then treated with exogenous ethylene and followed by ripening at 25°C for 5 days. Chilling injury symptoms such as pulp water soaking were observed in fruit stored at 7°C on 20 days, whereas the coloration and softening were completely blocked after 25 days, Large differences in the changes in the expression levels of twenty two genes involved in ethylene were seen during 7°C-storage with chilling injury. Those genes with altered expression could be divided into three groups: the group of genes that were up-regulated, including ACS1/2/3, EIN2, EIN3s/EIL1, CTR1/2/3, and ERF1/3/4; the group of genes that were down-regulated, including ACO3, ETR1, CTR4, EBF2, and ERF2; and the group of genes that were un-regulated, including ACO1/2, ERS, and EBF1. The results also showed that pulp firmness had a significantly positive correlation with the expression of ACS2, ACO1, CTR1/4, EIN3a/b, and EBF1/2 in fruit without chilling injury. This positive correlation was changed to negative one in fruit after storage at 7°C for 25 days with chilling injury. The coloring index displayed significantly negative correlations with the expression levels of ACS2, ACO1/2, CTR4, EIN3a/b, ERF3 in fruit without chilling injury, but these correlations were changed into the positive ones in fruit after storage at 7°C for 25 days with chilling injury. All together, these results indicate that these genes may play important roles in the abnormal softening and coloration with chilling injury in papaya.

A new 6-oxygenated coumarin, pygmaeoherin, was isolated from roots of PYGMAEOPREMNA HERBACEA. Its structure was determined by spectroscopic methods. An NOE experiment played an important role in confirming the structure.