Assessment of the optical properties with physicochemical properties and cell wall polysaccharides of 'Korla' pear flesh during Alternaria alternata-induced disease development.

Cell wall polysaccharides and physicochemical properties are the major quality characteristics of fruit, but they are significantly affected by the postharvest disease. In this study, the influence of Alternaria alternata-induced disease on the contents of cell wall polysaccharides and physicochemical properties in 'Korla' pear flesh during storage, as well as their relationships of the optical absorption (µa) and reduced scattering (µs') were explored. The infected pear had lower individual sugars, covalent-soluble pectin, cellulose and hemicellulose contents than the healthy ones. The successive decreases of µa and increases of µs' in pears were observed while the process of pathogen infection. Path-coefficient analysis indicated the ionic-soluble pectin was the main reason responsible for the change of µs' in infected pear at 675 nm and 980 nm. This study indicated the optical properties have the possibility to present the physicochemical characteristics and cell wall polysaccharides of pears during postharvest pathogen infection.

Evaluation of structural and physicochemical properties of octenyl succinic anhydride modified sweet potato starch with different degrees of substitution.

Octenyl succinic anhydride modified sweet potato starch (OSA-SPS) were synthesized in different degrees of substitution (DS) from 0.0073 to 0.0153. Unlike sweet potato starch (SPS), two additional characteristic peaks were detected at 1,572 and 1,724 cm-1 from the Fourier Transform-Infrared spectroscopy in OSA-SPS and their intensities were generally increased with the elevation in DS. Scanning electron microscopy and X-ray diffraction analyses revealed that the esterification did not alter the initial shape of starch granules and mainly occurred on the surface of starch pellets. In addition, OSA-SPS possessed higher transmittance, viscosity and stability, lower gelatinization temperature, and shorter gelatinization time than SPS. The changes of these properties of SPS after the esterification with OSA would be more conducive to its application in food and other fields. PRACTICAL APPLICATION: Octenyl succinic anhydride modified starch (OSAS), as a relatively novel amphiphilic surfactant, have been applied to the processing of many products due to its special hydrophilicity and lipophilicity. The structural and physicochemical properties of sweet potato starch (SPS) and octenyl succinic anhydride modified sweet potato starch (OSA-SPS) with different degrees of substitution (DS) were systematically analyzed in this research. The findings give fundamental understanding of OSA-SPS and provide a basic reference for its application in industries including food, cosmetics, textiles, and so on.

Hot air treatment reduces postharvest decay and delays softening of cherry tomato by regulating gene expression and activities of cell wall-degrading enzymes.

BACKGROUND: Fruit softening facilitates pathogen infection and postharvest decay, leading to the reduction of shelf-life. Hot air (HA) treatment at 38 °C for 12 h is effective in reducing postharvest disease and chilling injury of tomato fruit. To explore the effect and mechanism of HA treatment on reducing postharvest decay and softening of cherry tomato, fruit at the mature green stage were treated with HA and then stored at 20 °C for 15 days. Changes in natural decay incidence, firmness, cell wall compositions, activities and gene expression of cell wall-degrading enzymes of cherry tomatoes were assessed. RESULTS: HA treatment reduced natural decay incidence, postponed the firmness decline, inhibited the respiration rate and ethylene production, and retarded pectin solubilisation and cellulose degradation of cherry tomatoes. Enzymatic activities and gene expression of pectin methylesterase, polygalacturonase, cellulase and ß-galactosidase were inhibited by HA treatment. In addition, the gene expression of LeEXP1 was reduced, while LeEXT was up-regulated after HA treatment. CONCLUSIONS: Our findings suggested that HA treatment could inhibit cell wall degradation and postpone softening of cherry tomatoes by regulating gene expression and activities of cell wall-degrading enzymes, resulting in the reduction of postharvest decay. © 2017 Society of Chemical Industry.

Hot Air Treatment Induces Disease Resistance through Activating the Phenylpropanoid Metabolism in Cherry Tomato Fruit.

To explore the effects of hot air (HA, 38 °C for 12 h) treatment on the phenylpropanoid metabolism in cherry tomatoes, phenylpropanoid metabolite levels and the activities and expression of key enzymes were analyzed in HA-treated fruit. HA treatment enhanced phenylpropanoid metabolism, as evidenced by elevated levels of phenolics and flavonoids, higher activities of phenylalanine ammonia-lyase and cinnamate-4-hydroxylase, and upregulated expression of LeCHS, LeCHI, LeF3H, and LeFLS. Levels of several phenylpropanoid metabolites were higher after HA treatment, including p-coumaric acid, caffeic acid, chlorogenic acid, isoquercitrin, quercetin, and rutin. These metabolic changes may be related to the reduced disease incidence and smaller lesion diameters observed in HA-treated fruit inoculated with Alternaria alternata (black mold) or Botrytis cinerea (gray mold). The results suggest that HA treatment induces disease resistance by activating the phenylpropanoid pathway in cherry tomato fruit.

Antitumor, Antioxidant, and Nitrite Scavenging Effects of Chinese Water Chestnut (Eleocharis dulcis) Peel Flavonoids.

The preparation, quantification, and characterization of flavonoid compounds from Chinese water chestnut peel (CWCP) flavonoid extract and ethyl acetate fraction (EF), n-butanol fraction, and water fraction were studied. Among these, EF showed the maximum free radical levels (IC50 values of 0.36, 0.40, and 0.37 mg/mL for DPPH•, ABTS•+ , and •OH, respectively), nitrite scavenging effects (IC50 = 1.89 mg/mL), and A549 cell inhibitory activities (IC50 = 776.12 µg/mL) with the highest value of total flavonoid content (TFC, 421.32 mg/g). Moreover, the contents of 8 flavonoids in this fraction were quantified using high-performance liquid chromatography, and fisetin, diosmetin, luteolin, and tectorigenin were the 4 major flavonoids with levels of 31.66, 29.91, 13.69, and 12.41 mg/g, respectively. Luteolin produced a greater inhibition of human lung cancer A549 cells (IC50 = 59.60 µg/mL) than did fisetin, diosmetin, and tectorigenin. Flow cytometry revealed that the cellular mechanisms of luteolin inhibition of A549 cells were achieved via the induction of cell proliferation arrest at G1 phase and apoptosis/necrosis. Our findings suggest that flavonoids are closely associated with antitumor, antioxidant, and nitrite scavenging effects of CWCP.

[Effect of Telbivudine Tablet Combined Jianpi Bushen Recipe on HBV Specific Cytotoxic T Lymphocyte and HBeAg Seroconversion in Patients with HBeAg Positive Chronic Hepatitis B].

OBJECTIVE: To explore the effect of Telbivudine (LDT) Tablet combined with Jianpi Bushen Recipe (JBR) on serum hepatitis B virus (HBV) specific cytotoxic T lymphocyte (CTL) and HBeAg seroconversion in chronic hepatitis B (CHB) patients. METHODS: Totally 90 HBeAg-positive and human leukocyte antigen (HLA)-A2 positive CHB patients were randomly assigned to the treatment group and the control group, 45 cases in each group. Patients in the treatment group took LDT Tablet (600 mg, once per day) combined with JBR granule (twice per day), while those in the control group took LDT Tablet alone. The therapeutic course for all was one year. HBV DNA negative conversion rate, HBeAg seroconversion rate, and level of HBV specific CTL were compared after 1 year treatment; liver function, drug resistance mutations, and adverse reactions were also compared between the two groups. RESULTS: After 1 year treatment, HBV DNA negative conversion rate and HBeAg seroconversion rate were 88.89% (40/45) and 40.00% (18/45) in the treatment group, higher than those of the control group [68.89% (31/45) and 20.00% (9/45)], with statistical difference (P < 0.05). Level of HBV specific CTL in the treatment group was 0.78% +/- 0.09% after treatment, higher than that of the control group after 1 year treatment (0.54% +/- 0.11%) and that before treatment (0.36% +/- 0.07%), with statistical difference (P < 0.01). Level of HBV specific CTL in 27 patients with HBeAg seroconversion was 0.81% 0.10%, higher than that of 63 patients without HBeAg seroconversion (0.60% +/- 0.09%), with statistical difference (P < 0.01). ALT returned to normal in 44 cases of the treatment group (97.78%), while it was 42 cases (93.33%) of the control group, with no statistical difference between the two groups (P > 0.05). Total bilirubin (TBil) in the two groups all turned to normal. rtM204I variation occurred in 1 case (2.22%) of the treatment group and 2 cases (4.44%) in the control group. No obvious adverse reaction occurred in the two groups. CONCLUSION: LDT Tablet combined with JBR could elevate levels of HBV specific CTL and HBeAg seroconversion in CHB patients.

[Effect of compound qizhu granule on cellular immunity of chronic hepatitis B patients].

OBJECTIVE: To explore the effect of compound qizhu granule (CQG) on cellular immunity of chronic hepatitis B (CHB) patients. METHODS: Totally 103 CHB patients treated with lamivudin (LAM) for 6 months, who had partial virological response (HBeAg positive) were randomly assigned to two groups, 50 in the treatment group and 53 in the control group. All patients took LAM 100 mg (once a day) plus ADV 10 mg (once a day). Patients in the treatment group additionally took CQG, one dose per day. After one-year treatment hepatitis B virus (HBV) DNA negative rates, HBeAg seroconversion, levels of HBV specific cytotoxic T lymphocyte (CTL), non-specific CTL and natural killing (NK) cells were compared between the two groups. RESULTS: After 1-year treatment, HBV DNA negative rate of the treatment group was 88: 0% in 44 cases, slightly higher than that of the control group (41 cases, 77.4%), but with no statistical difference (P >0.05). HBeAg seroconversion of the treatment group was 32.0% in 16 cases, higher than that of the control group (8 cases, 15.1%), with statistical difference (P <0.05). Levels of HBV specific CTL (0.79%±0. 07%), non-specific CTL (19.4%±1.8%) and NK cells (14. 1%± 1.5%) of the treatment group were higher than those of the control group (0.58% ± 0.08%, 17.5% ± 1.7%, and 11.1%±1.5%, respectively; allP <0.01). CONCLUSION: Treating CHB patients with partial virological response by ADV plus CQG could improve specific and non-specific cellular immunity, thereby elevating HBeAg seroconversion rate.

Association of feature gene expression with structural fingerprints of chemical compounds.

Exploring the relationship between a chemical structure and its biological function is of great importance for drug discovery. For understanding the mechanisms of drug action, researchers traditionally focused on the molecular structures in the context of interactions with targets. The newly emerged high-throughput "omics" technology opened a new dimension to study the structure-function relationship of chemicals. Previous studies made attempts to introduce transcriptomics data into chemical function investigation. But little effort has been made to link structural fingerprints of compounds with defined intracellular functions, i.e. expression of particular genes and altered pathways. By integrating the chemical structural information with the gene expression profiles of chemical-treated cells, we developed a novel method to associate the structural difference between compounds with the expression of a definite set of genes, which were called feature genes. A subtraction protocol was designed to extract a minimum gene set related to chemical structural features, which can be utilized in practice as markers for drug screening. Case studies demonstrated that our approach is capable of finding feature genes associated with chemical structural fingerprints.

Effects of heat treatment on wound healing in gala and red fuji apple fruits.

This study investigated the effects of heat treatment (hot air at 38 degrees C for 4 days) on wound healing in Gala and Red Fuji apple fruits (Malus domestica Borkh.) and the possible mechanism. Wounded apples were healed at either 20 or 38 degrees C for 4 days. During the treatment, ethylene, phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO), hydrogen peroxide (H(2)O(2)), and phenolic and lignin contents were measured. Following the treatment, healed wounds were inoculated with Penicillium expansum, Botrytis cinerea, and Colletotrichum acutatum, and then the decay development was observed. Results revealed that the influence of heating on wound healing in apple fruit was cultivar dependent. Compared with fruits healed at 20 degrees C, heating at 38 degrees C had a pejorative effect on wound healing in Gala apples. However, identical treatment enhanced wound healing in Red Fuji apples. Heating sharply reduced ethylene evolution, PAL and POD activity, and the accumulation of phenolic compounds and lignin around wounds in Gala apples. Alternatively, in Red Fuji apples, treatment at 38 degrees C significantly improved ethylene evolution and peroxide (H(2)O(2)) content at the first two days of treatment. In addition, both PAL and POD activities, and contents of phenolic compounds and lignin around wounds increased. Our findings suggest that this discrepancy in the effect of heat treatment on wound healing is due to different effects on ethylene evolution in cultivars of apple fruit.

A combination of heat treatment and Pichia guilliermondii prevents cherry tomato spoilage by fungi.

This study investigated the effectiveness of heat treatment and Pichia guilliermondii, either alone or in combination, to combat postharvest fungal spoilage in cherry tomato fruit. In vitro experiments demonstrated that heat treatment at 38 degrees C significantly inhibited mycelial growth of three different pathogens (Botrytis cinerea, Alternaria alternata and Rhizopus stolonifer Ehrenb). In vivo experiments unveiled that either heat treatment or P. guilliermondii reduced decay caused by these pathogens. Furthermore, a combination of heat treatment followed by the application of P. guilliermondii (H+P) provided the best efficacy in prevention of cherry tomato from fungal spoilage. Following, H+P treatment, electronic nose detected a reduction of volatility in cherry tomato fruit odor, an indicator of preserving fruit's freshness. Scanning electron microscopy unveiled that heat treatment at 38 degrees C for 24h inhibited hyphae growth and spore germination of R. stolonifer Ehrenb while P. guilliermondii multiplied rapidly on fruit wounds, and its cells had a strong capability of adhesion to the hyphae of R. stolonifer Ehrenb. However, heat treatment also seriously injured P. guilliermondii, therefore P. guilliermondii should be applied after heat treatment. A combination of heat treatment and P. guilliermondii is one of the most effective techniques at controlling postharvest fungal spoilage in cherry tomato fruit.

Heat treatment in combination with antagonistic yeast reduces diseases and elicits the active defense responses in harvested cherry tomato fruit.

This study investigated the effects of heat treatment (hot air at 38 degrees C) and antagonistic yeast (Pichia guilliermondii) alone or in combination against postharvest diseases (Botrytis cinerea, Alternaria alternata and Rhizopus nigricans) on cherry tomato fruit, and evaluated the elicitation of active defense responses. Results showed that heat treatment at 38 degrees C for 24 h in combination with P. guilliermondii at 1 x 10(8) CFU mL(-1) was the most effective approach to reduce various infections on cherry tomato fruit's wounds. Moreover, the combined heat and P. guilliermondii treatment stimulated a rapid increase of H(2)O(2) and higher lignin deposition in cherry tomato fruit showing that the oxidative burst and biological synthesis of lignin might play important roles in the fruit's active defense responses. In addition, the reduction of the fruit's susceptibility to pathogens by the combined treatment was positively correlated with higher activities of phenylalanine ammonia-lyase (PAL) and beta-1,3-glucanase in cherry tomato fruits, both of which are associated with plant defense responses.