Constitutive Overexpression of an NB-ARC Gene from Wild Chinese Vitis quinquangularis in Arabidopsis thaliana Enhances Resistance to Phytopathogenic Oomycete and Bacteria.

Resistance (R) genes were used to recognize pathogen effectors directly or indirectly in plants and activate defense signal pathways. Most of these R proteins consist of a nucleotide-binding adaptor (NB-ARC) domain, a leucine-rich repeat (LRR) domain and some also have a coiled-coil (CC) structure. In this study, we cloned a gene which encodes the CC-NB-ARC-LRR R protein (VqCNL) from Chinese wild grapevine Vitis. quinquangularis accession 'Dan-2'. The transcript of VqCNL was obviously induced by inoculation with Plasmopara viticola and the salicylic acid (SA) treatment. The results of sequence analysis showed that the VqCNL gene contained a CC domain at the N-terminus, along with an NB-ARC and an LRR domain at the C-terminus. We transferred this gene into wildtype Arabidopsis and treated transgenic lines with Hyaloperonospora arabidopsidis (Hpa) and Pseudomonas syringae pv. tomato DC3000 (Pst DC3000); the results demonstrated that VqCNL promotes broad spectrum resistance to pathogens. Furthermore, qPCR analysis displayed that VqCNL may display a significant function in disease resistance via activating SA signaling pathways. In general, these conclusions primarily demonstrated that VqCNL enhances the disease resistance level in plants and contributes to future research of the R gene identification for grape breeding biotechnology.

Bamboo leaf extract treatment alleviates the surface browning of fresh-cut apple by regulating membrane lipid metabolism and antioxidant properties.

BACKGROUND: The effect of bamboo leaf extract (BLE) on controlling the browning of fresh-cut apple stored at 4 °C was investigated. Browning index, H2 O2 content, O2 - production rate, malondialdehyde (MDA) contents, total phenolic content (TPC) and soluble quinone content (SQC), the activities of polyphenol oxidase (PPO), peroxidase (POD), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), DPPH (2,2-diphenyl-2-picryl-hydrazyl) and ABTS [2,2-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid)] radical scavenging activities, and the expression of genes related to browning were all investigated. RESULTS: BLE effectively alleviated the surface browning of fresh-cut apple, accompanied by a reduction in SQC, LOX activity, H2 O2 , O2 - production rate and MDA accumulation. Furthermore, BLE treatment enhanced the TPC, enzymatic (SOD, CAT, APX and POD) and non-enzymatic antioxidant activities. Principal component analysis and Pearson correlation analysis found the browning inhibition by BLE is not through the reduction of phenolic substrates and PPO activity. CONCLUSION: BLE controls the browning of fresh-cut apple by increasing the antioxidant capacity to scavenge ROS, which could alleviate oxidative damage and maintain the membrane integrity. © 2023 Society of Chemical Industry.

Influences of water level fluctuation on water exchange and nutrient distribution in a bay: Evidence from the Xiangxi Bay, Three Gorges Reservoir.

Following the Three Gorges Reservoir (TGR) impoundment, many tributaries were turned into bays; hydrodynamic conditions of TGR profoundly changed the residence time, temperature, and nutrient distributions of bays, and nutrient enrichment occurred in these bays. However, little research has been done on the effects of water level qqfluctuations (WLFs) of TGR on the bay. In this study, Xiangxi Bay (XXB), one of the tributaries of TGR, was selected as the delegate to construct and calibrate a two-dimensional hydrodynamic-temperature-tracer-water quality model based on the CE-QUAL-W2. The results were the following: 1) In spring, as total nitrogen (TN) in the TGR tended to be higher than that in the XXB, the downward WLF increased water exchange, TGR-XXB nutrient flux and TN in the epilimnion of the XXB, and decreased the water exchange and TN in the hypolimnion of the XXB. The upward WLF did the opposite. The situation would be reversed in autumn. 2) Under a larger magnitude or a shorter period of WLF, its corresponding effects on the water exchange and TN increased. 2) Both the downward and upward modes of WLF helped to decrease the thermal stratification of XXB. 4) The upward/downward WLF could be used to decrease the epilimnetic TN of XXB in spring/autumn, and was suggested to reduce the local algal bloom. The WLFs by the TGR regulation could profoundly change the water exchange and nutrient distribution in the bay, which helped to control nutrient concentrations and prevent algal blooms.

Heterologous VvDREB2c Expression Improves Heat Tolerance in Arabidopsis by Inducing Photoprotective Responses.

Extreme temperatures limit grape production and sustainability. Dehydration-responsive element-binding (DREB) transcription factors affect plant responses to temperature related stresses. Therefore, we investigated the role of VvDREB2c, a DREB-coding gene, found in grapes (Vitis vinifera L.). Protein characterization revealed that VvDREB2c is localized to the nucleus and that its AP2/ERF domain contains three ß-sheets and one α-helix sheet. Analysis of the VvDREB2c promoter region revealed the presence of light-, hormone-, and stress-related cis-acting elements. Furthermore, we observed that the heterologous expression of VvDREB2c in Arabidopsis improved growth, drought tolerance, and heat tolerance. Furthermore, it improved the leaf quantum yield of regulated energy dissipation [Y(NPQ)], elevated the activities of RuBisCO, and phosphoenolpyruvate carboxylase and reduced the quantum yield of non-regulated energy dissipation [Y(NO)] in plants exposed to high temperatures. VvDREB2c-overexpressing lines also specifically upregulated several photosynthesis-related genes (CSD2, HSP21, and MYB102). In addition, VvDREB2c-overexpressing lines reduced light damage and enhanced photoprotective ability by dissipating excess light energy and converting it into heat, which eventually improves tolerance to high temperature. The contents of abscisic acid, jasmonic acid, and salicylic acid and differentially expressed genes (DEGs) in the mitogen-activated protein kinase (MAPK) signaling pathway were affected by heat stress in VvDREB2c-overexpressing lines, which indicated that VvDREB2c positively regulates heat tolerance via a hormonal pathway in Arabidopsis. VvDREB2c promotes heat tolerance in Arabidopsis by exerting effects on photosynthesis, hormones, and growth conditions. This study may provide useful insights into the enrichment of the heat-tolerance pathways in plants.

Optimization of In Vitro Embryo Rescue and Development of a Kompetitive Allele-Specific PCR (KASP) Marker Related to Stenospermocarpic Seedlessness in Grape (Vitis vinifera L.).

Seedlessness is one of the highest valued agronomic traits in grapes. Embryo rescue in combination with marker-assisted selection have been widely applied in seedless grape breeding due to the advantages of increasing the ratio of seedless progenies and shortening the breeding cycle. However, the large number of deformed seedlings produced during embryo rescue and the lack of fast, efficient, and low-cost markers severely inhibit the process of seedless grape breeding. In this study, a total of eighty-three grape cultivars (51 seedless and 32 seeded) with diverse genetic backgrounds and two populations derived from embryo rescue, including 113 F1 hybrid individuals (60 seedless and 53 seeded), were utilized. We screened suitable media for converting malformed seedlings into normal seedlings, analyzed the association between the SNP in VviAGL11 and seeded/seedless phenotype, and developed a KASP marker related to stenospermocarpic seedlessness. Our results indicated that the transformation rate of 37.8% was obtained with MS medium supplemented with 2.0 mg·L-1 of 6-BA and 0.5 mg·L-1 of IBA. The presence of an A nucleotide allele at position chr18:26889437 was further confirmed to be fully associated with the stenospermocarpic seedlessness phenotype. The developed KASP marker, based on the verified SNP locus in VviAGL11, successfully distinguished the seedless and seeded genotypes with high precision and throughput. The results will contribute to enhancing the efficiency of embryo rescue and facilitate parent selection and early selection of seedless offspring with molecular markers, thereby accelerating the breeding process in seedless table grapes.

In silico, synthesis and anticancer evaluation of benzamide tryptamine derivatives as novel eEF2K inhibitors.

Eukaryotic elongation factor 2 kinase (eEF2K), a member of the atypical α-kinase family, is highly expressed in a variety of tumor tissues. Inhibition of eEF2K function can effectively kill cancer cells without affecting the function of normal cells. Therefore, eEF2K is a promising new target for cancer therapy. In this study, a series of benzamide tryptamine derivatives were designed and synthesized as novel eEF2K inhibitors. The druggability properties of the synthesized compounds were predicted in silico and performed well. The MTT assay indicated that most of these compounds displayed good antiproliferative activity against human leukemia CCRF-CEM and K562 cell lines. The structure-activity relationship (SAR) revealed that substituents with different electronic effects on the C5 position of indole ring or C2', C4' positions of benzene ring have a great influence on the anti-proliferative activity. Among them, 5j demonstrated the highest anti-proliferative activity with IC50 value of 1.63-3.54 µM. this compound displayed an effective eEF2K inhibition by down-regulated the level of phosphorylated eEF2 in CCRF-CEM cells. Additionally, the western blot analysis further revealed that 5j also significantly affected eEF2K-related signaling pathways. Anticancer mechanism studies have shown that 5j arrested the cell cycle in G0/G1 and induced CCRF-CEM cells apoptosis. Furthermore, 5j activated cleaved caspase-9, 8, 3 and cleaved PARP in a time-dependent manner, which suggesting that 5j induced cancer cells apoptosis through both intrinsic and extrinsic pathways. In summary, benzamide tryptamine derivative 5j represents a novel and promising lead structure for the development of eEF2K inhibitors in cancer therapy.

Randomized Control Study on Hemoperfusion Combined with Hemodialysis versus Standard Hemodialysis: Effects on Middle-Molecular-Weight Toxins and Uremic Pruritus.

INTRODUCTION: Classic hemodialysis schedules present inadequate middle-molecular-weight toxin clearance due to limitations of membrane-based separation processes. Accumulation of uremic retention solutes may result in specific symptoms (e.g., pruritus) and may affect clinical outcome and patient's quality of life. Hemoperfusion (HP) is a blood purification modality based on adsorption that can overcome such limitations, and thus, it may be interesting to test the efficacy of at least one session per week of HP combined with hemodialysis. This is a randomized, open-label trial, controlled, multicenter clinical study to investigate the effect of long-term HP combined with hemodialysis on middle-molecular-weight toxins and uremic pruritus in maintenance hemodialysis (MHD) patients. METHODS: 438 MHD patients from 37 HD centers in China with end-stage kidney disease (63.9% males, mean age 51 years) suffering from chronic intractable pruritus were enrolled in the study. Eligible patients were randomized into four groups: low-flux hemodialysis (LFHD), high-flux hemodialysis (HFHD), HP + LFHD, and HP + HFHD at a 1:1:1:1 ratio. Beta-2 microglobulin (ß2M) and parathyroid hormone (PTH) were measured at baseline, 3-6, and 12 months. At the same time points, the pruritus score was evaluated. The primary outcome was the reduction of ß2M and PTH, while the secondary outcome was the reduction of the pruritus score. RESULTS: In the two groups HP + LFHD and HP + HFHD, there was a significant decrease of ß2M and PTH levels after 12 months compared to the control groups. No significant differences were noted between HP + LFHD and HP + HFHD. Pruritus score reduction was 63% in the HP + LFHD group and 51% in the HP + HFHD group, respectively. CONCLUSION: The long-term HP + HD can reduce ß2M and PTH levels and improve pruritus in MHD patients independently on the use of high- or low-flux dialyzers, showing that the results are linked to the effect of adsorption.

MicroRNA-423-5p as a biomarker for early diagnosis and outcome prediction of acute kidney injury in patients with acute decompensated heart failure.

OBJECTIVE: To evaluate the clinical significance of serum and urinary microRNA-423-5p in the prediction of acute kidney injury onset and survival in patients with acute decompensated heart failure. METHODS: A total of 180 acute decompensated heart failure patients, including 57 acute kidney injury cases and 123 non-acute kidney injury cases, were included in this study. Serum and urinary neutrophil gelatinase-associated lipocalin, a biomarker of renal injury of acute kidney injury, was detected using an enzyme-linked immunosorbent assay. Expression of microRNA-423-5p in serum and urine samples was examined using quantitative real-time polymerase chain reaction. The clinical significance of microRNA-423-5p was evaluated using receiver operating characteristic curve and Kaplan-Meier survival analysis. RESULTS: The levels of neutrophil gelatinase-associated lipocalin and microRNA-423-5p in serum and urine samples were elevated in patients with acute kidney injury compared with the non-acute kidney injury cases (all P < 0.05). Serum and urinary microRNA-423-5p had relatively high predictive performance for acute kidney injury onset in acute decompensated heart failure patients, and this predictive value was more significant when combined with urinary neutrophil gelatinase-associated lipocalin. In addition, serum and urinary elevated levels of microRNA-423-5p predicted a poor 180-day survival in the acute kidney injury group. CONCLUSION: Increased serum and urinary microRNA-423-5p can predict the occurrence of acute kidney injury in acute decompensated heart failure patients, and is associated with poor survival of acute kidney injury patients. In addition, the diagnostic value of urine neutrophil gelatinase-associated lipocalin for the early screening of acute kidney injury from acute decompensated heart failure patients might be improved by considering the changes in urinary microRNA-423-5p.

Cleavage rules of mass spectrometry fragments and rapid identification of chemical components of Radix Paeoniae Alba using UHPLC-Q-TOF-MS.

INTRODUCTION: Radix Paeoniae Alba (RPA) presents several pharmacological effects, including analgesia, liver protection, and toxicity reduction. RPA consists mostly of monoterpenes and their glycosides, tannins, flavonoids, and organic acids, with monoterpenes being the main active pharmaceutical ingredients. OBJECTIVE: To establish an effective method for rapid classification and identification of the main monoterpenes, flavonoids, and organic acids in RPA. METHODS: We used ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and data post-processing technology to rapidly classify and identify the monoterpenoids, flavonoids, and organic acids in RPA. We also summarised the diagnostic product ions and neutral losses of monoterpenoids, flavonoids, and organic acids in RPA reported in the literature. RESULTS: We identified 24 components, namely 18 monoterpenoids, one flavonoid, and five organic acids. CONCLUSION: In this study, we analysed the chemically active pharmaceutical ingredients and assessed the quality of RPA. In addition, we demonstrated that UHPLC-Q-TOF-MS can be used to qualitatively classify and identify the variety of chemical components of traditional Chinese medicines (TCMs) to a certain extent. Moreover, we confirmed that mass spectrometry can be used to identify the components of TCMs.

Ectopic expression of a grape nitrate transporter VvNPF6.5 improves nitrate content and nitrogen use efficiency in Arabidopsis.

BACKGROUND: Nitrate plays an important role in grapevines vegetative and reproductive development. However, how grapevines uptake, translocate and utilize nitrate and the molecular mechanism still remains to be investigated. RESULTS: In this study, we report the functional characterization of VvNPF6.5, a member of nitrate transporter 1/peptide transporter family (NRT1/PTR/NPF) in Vitis vinifera. Subcellular localization in Arabidopsis protoplasts indicated that VvNPF6.5 is plasma membrane localized. Quantitative RT-PCR analysis indicated that VvNPF6.5 is expressed predominantly in roots and stems and its expression is rapidly induced by nitrate. Functional characterization using cRNA-injected Xenopus laevis oocytes showed that VvNPF6.5 uptake nitrate in a pH dependent way and function as a dual-affinity nitrate transporter involved in both high- and low-affinity nitrate uptake. Further ectopic expression of VvNPF6.5 in Arabidopsis resulted in more 15NO3- accumulation in shoots and roots and significantly improved nitrogen use efficiency (NUE). Moreover, VvNPF6.5 might participate in the nitrate signaling by positively regulating the expression of primary nitrate response genes. CONCLUSION: Our results suggested that VvNPF6.5 encodes a pH-dependent, dual-affinity nitrate transporter. VvNPF6.5 regulates nitrate uptake and allocation in grapevines and is involved in primary nitrate response.

In vivo biological safety evaluation of an iron-based bioresorbable drug-eluting stent.

Bioresorbable stents (BRS) are investigated and designed to revascularize occluded arteries. The iron-based bioresorbable stent is a promising device in interventional therapies, although it's corrosion and bioresorption rate remain challenging. In this work, we introduced a novel nitrided iron coronary stent (IBS) with enhanced degradation rate compared with pure iron stent. To evaluate the biosafety of this device, a sub-chronic systemic toxicity study was conducted and a stainless steel stent (Supporter™) served as a control. Here, the bioresorbable stent was first evaluated in rat abdominal aortic implantation model. When subjected to exaggerated exposure dose, no clinical signs of toxicity or mortality were observed in either, the IBS group or the control group. Histopathological examinations showed the corrosion particles of iron were encapsulated by fibrocytes and engulfed by macrophages, indicating that the degradation of iron was in the early stage. Our results demonstrated that the nitrided iron stent did not induce systemic toxicity under the experimental conditions.

The Prognostic Value of Soluble ST2 in Maintenance Hemodialysis Patients: A Meta-Analysis.

BACKGROUND: Much controversy remains in the literature with respect to whether soluble suppression of tumorigenicity 2 (sST2) can serve to predict all-cause death in patients undergoing maintenance hemodialysis (MHD). This meta-analysis therefore sought to analyze extant datasets exploring the association between these 2 variables in MHD patients in order to draw relevant conclusions. METHODS: Articles published through December 2018 in PubMed and Embase were independently reviewed by 2 authors to identify relevant articles, and STATA 12.0 was used for statistical analyses of relevant results and study parameters. RESULTS: In total, we identified 4 relevant studies that were incorporated into this meta-analysis. These studies included a total of 1,924 participants (60% male, mean follow-up 911 days). The combined study results suggested that increased levels of sST2 were significantly linked to a 2.23 fold rise in all-cause mortality (hazard ratio [HR] 2.23, 95% CI 1.81-2.75). Subgroup analyses confirmed that this same association was true in patients undergoing hemodialysis (HR 2.17, 95% CI 1.74-2.71), which indicated that the increased levels of sST2 were significantly linked to a 2.17 fold rise in all-cause mortality. CONCLUSIONS: This analysis suggests that there is a significant link between elevated levels of sST2 and death in patients undergoing MHD. Further large-scale trials, however, will be needed to fully validate these findings and their clinical relevance.

Effect of atmospheric cold plasma treatment on antioxidant activities and reactive oxygen species production in postharvest blueberries during storage.

BACKGROUND: Blueberry is universally acknowledged as a kind of berry rich in antioxidants. Cold plasma, an emerging non-thermal treatment technology, has been proved to be able to maintain or improve the antioxidant level while inactivating the microorganisms on the surface of fruits and vegetables. Postharvest blueberries were treated with atmospheric cold plasma (ACP; 12 kV, 5 kHz) for 0 s (Control), 30 s (ACP-30), 60 s (ACP-60), and 90 s (ACP-90) in this study, and the effects of ACP on the antimicrobial properties, antioxidant activities, and reactive oxygen species (ROS) production were investigated during storage at 4 ± 1 °C for 40 days. RESULTS: Total aerobic bacteria and mold populations on ACP-treated blueberries decreased significantly in a time-dependent manner (P < 0.05), and decreased by 0.34-1.24 and 0.57-0.87 log10 CFU g-1 respectively on ACP-60-treated blueberries during storage. The decay rate of blueberries was decreased by 5.8-11.7% and the decrease of blueberry firmness was slowed down by ACP-60. But the total phenol, anthocyanin, and ascorbic acid contents increased, and superoxide dismutase, catalase, and peroxidase activities were enhanced in ACP-treated blueberries. The free radical scavenging activity and total antioxidant capacity (T-AOC) were enhanced. Hydrogen peroxide (H2 O2 ) and superoxide anion (O2 - ) production rates declined by 27.3% and 41.3% at day 40 of storage, respectively. CONCLUSION: It is suggested that ACP may be a promising non-thermal treatment technology for postharvest sterilization and preservation of blueberry under suitable conditions. © 2020 Society of Chemical Industry.

An untargeted metabolomic approach reveals significant postharvest alterations in vitamin metabolism in response to LED irradiation in pak-choi (Brassica campestris L. ssp. chinensis (L.) Makino var. communis Tsen et Lee).

The main objective of this study was to investigate the effect of low-level light emitting diode (LED) irradiation on the metabolite profile of pak-choi. A total of 633 different molecular features (MFs) were identified among sample groups (initial, dark-treated, light-treated) using an untargeted metabolomic approach. The identified metabolites were associated with 24 different metabolic pathways. Four of the pathways including carbon pool by folate, folate biosynthesis, thiamine metabolism, and glutathione metabolism, all of which are associated with vitamin biosynthesis, changed significantly. Metabolites in four of the pathways exhibited significant differences from the control in response to LED irradiation. Additionally, porphyrin and chlorophyll metabolism, as well as glucosinolate biosynthesis, riboflavin metabolism, and carotenoid biosynthesis were positively induced by LED irradiation. These results indicate that postharvest LED illumination represents a potential tool for modifying the metabolic profile of pak-choi to maintain quality and nutritional levels.

Androgen deprivation therapy with chemotherapy or abiraterone for patients with metastatic hormone-naive prostate cancer: a systematic review and meta-analysis.

Patients with metastasis prostate cancer underwent androgen deprivation therapy (ADT) in the considering of the leading role of androgen receptor pathway. However, the resistance occurred within 1 year or more. The combination of cytotoxic chemotherapy and abiraterone for ADT therapy was performed in recent randomized controlled trials. The meta-analysis was focused on the treatment comparisons between additional treatment with ADT and ADT alone. A significant difference was observed that the overall survival benefit of early and active additional treatment with ADT in patients with hormone-sensitive metastatic prostate cancer. However, a great proportion of patients with metastatic disease have metastases after receiving ADT. It will be important to further improve the treatment options.

Ectopic Calcification of Fibrin Sheath on the Catheter.

We describe a case of hemodialysis catheter that appeared to be encased in a sleeve-shaped fibrous sheath with calcification. Ectopic calcification is a serious complication in hemodialysis patients with calcium-phosphorus metabolism disorder. Clinical awareness and understanding of this condition is imperative to the prevention and management of ectopic calcification.

The effect of hemodialysis on ocular changes in patients with the end-stage renal disease.

Background: Numerous metabolic parameters can be changed during hemodialysis in the end-stage renal disease (ESRD) caused by systemic diseases, such as diabetes mellitus, hypertension. Some ocular parameters also can be variable due to the changes after hemodialysis. This study evaluates the effects of ocular parameters, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), retinal arteriolar caliber (RAC), retinal venular calibre (RVC), in ESRD patients following hemodialysis. Materials and methods: Two-hundred and two ESRD patients were recruited resulting in 404 eyes evaluations. All patients underwent hemodialysis in the Dialysis Unit of the Second Hospital of Tianjin Medical University. BCVA, CMT, IOP, SFCT, RAC and RVC were evaluated before and after hemodialysis. Systemic parameters were collected such as age, body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), duration of hemodialysis, body weight changes, high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDLC), very low density lipoprotein cholesterol (VLDLC), glycosylated hemoglobin (HbA1c). Results: The causes of ESRD patients included chronic glomerulonephritis (n = 65), diabetes mellitus (n = 60), hypertensive nephrosclerosis (n = 37), and other causes (n = 40). In our study, BCVA (p = .817), CMT (p = .252) and IOP (p = .978) did not significantly change after hemodialysis. SFCT significantly decreased from 254.29 ± 69.36 µm to 235.54 ± 659.90 µm (p = .002) following hemodialysis. SFCT changes were significantly correlated with SBP (p = .042) and body weight changes (p = .044). The RAC and RVC were dilated significantly (p = .033, p = .007). RVC changes were correlated with baseline DBP (p = .003), HDLC (p = .009), LDLC (p = .004) and changes in DBP (p = .037) and body weight (p = .001). Conclusion: Hemodialysis can affect various ocular parameters including SFCT, RAC and RVC, which changed significantly following hemodialysis. Whereas BCVA, IOP and CMT did not change after hemodialysis in ESRD patients. The systemic compensatory mechanisms of the changes in SBP, DBP, body weight following hemodialysis need further study.

Preparative Purification of Total Flavonoids from Sophora tonkinensis Gagnep. by Macroporous Resin Column Chromatography and Comparative Analysis of Flavonoid Profiles by HPLC-PAD.

For the full development and utilization of Sophora tonkinensis Gagnep., this study was primarily intended to established a simple and efficient approach for the preparative purification of total flavonoids from S. tonkinensis by macroporous resin column chromatography (MRCC). The adsorption and desorption characteristics of the total flavonoids on ten macroporous resins were first studied, and AB-8 resin was chosen as the most suitable, and the adsorption data were best fitted to the pseudo-second-order kinetics model and Langmuir isotherm model. Furthermore, the technological parameters for the purification of the total flavonoids were optimized using column chromatography. After a sample one-step purification procedure, the content of the total flavonoids increased by about 4.76-fold from 12.14% to 57.82%, with a recovery yield of 84.93%. In addition, the comparative analysis of the flavonoid extracts before and after purification was performed by high-performance liquid chromatography coupled with photodiode-array detection (HPLC-PAD). The results showed that the contents of six major flavonoids in the purified product were all higher than before the purification. Therefore, the AB-8 MRCC established in this work was a promising method for the industrial-scale purification of the total flavonoids from S. tonkinensis.

Effect of Methyl Jasmonate on Phenolic Accumulation in Wounded Broccoli.

In order to find an efficient way for broccoli to increase the phenolic content, this study intended primarily to elucidate the effect of methyl jasmonate (MeJA) treatment on the phenolic accumulation in broccoli. The optimum concentration of MeJA was studied first, and 10 µM MeJA was chosen as the most effective concentration to improve the phenolic content in wounded broccoli. Furthermore, in order to elucidate the effect of methyl jasmonate (MeJA) treatment on phenolic biosynthesis in broccoli, the key enzyme activities of phenylpropanoid metabolism, the total phenolic content (TPC), individual phenolic compounds (PC), antioxidant activity (AOX) and antioxidant metabolism-associated enzyme activities were investigated. Results show that MeJA treatment stimulated phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase (C4H), and 4-coumarin coenzyme A ligase (4CL) enzymes activities in phenylpropanoid metabolism, and inhibited the activity of polyphenol oxidase (PPO), and further accelerated the accumulation of the wound-induced rutin, caffeic acid, and cinnamic acid accumulation, which contributed to the result of the total phenolic content increasing by 34.8% and ferric reducing antioxidant power increasing by 154.9% in broccoli. These results demonstrate that MeJA in combination with wounding stress can induce phenylpropanoid metabolism for the wound-induced phenolic accumulation in broccoli.

Effect of ethanol treatment on the quality and volatiles production of blueberries after harvest.

BACKGROUND: Blueberries are appreciated by consumers for their rich natural antioxidants and their good nutritional and health functions. However, blueberries are very perishable due to microbial infection and metabolic aging after harvest. Ethanol has been shown to have the effect of controlling postharvest microorganisms and improving storage quality of fruits and vegetables. This study aimed to clarify the effects of ethanol on the appearance quality and flavor attributes of postharvest blueberries. Blueberries were treated with ethanol (250, 500, and 1000 µL L-1 ) and stored at 0 ± 0.5 °C, 90% relative humidity (RH), for 40 days. RESULTS: The results indicated that ethanol treatment could slow the decline of blueberry firmness and reduce the decay rate significantly in a dose-dependent manner. The soluble solids content (SSC) and titratable acidity (TA) of ethanol-treated blueberries increased significantly (P < 0.05), improving the taste of the blueberries. The activities of alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC) were stimulated with the accumulation of ethanol in blueberries, which catalyzed the conversion of ethanol, acetaldehyde, and pyruvate, increasing their levels in blueberries. More volatiles, especially esters, were detected in ethanol-treated blueberries, e.g. methyl acetate, ethyl acetate, ethyl propanoate, ethyl isobutyrate, ethyl 2-methylbutanoate, ethyl isovalerate, ethyl 3-methyl-2-butenoate, diethyl sebacate, and isopropyl myristate. CONCLUSION: The preservative effect of ethanol on blueberry was significantly affected by ethanol concentration. In this study, the effect of 500 µL L-1 ethanol fumigation on blueberry was the best in terms of appearance quality (firmness and decay rate) and flavor attributes (SSC, TA, and volatiles). © 2019 Society of Chemical Industry.