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The effects of high CO2 (5% and 10%), on respiratory metabolism and quality of sweet cherries ("Rainier" and "8–102" varieties), were evaluated following storage at 0°C for 60 d. Quality (respiration rate, weight loss, firmness, etc.) in sweet cherries was significantly improved by high CO2 in storage. And high CO2 enhanced pentose phosphate pathway, decreased in the glycolytic pathway and tricarboxylic acid cycle in aerobic respiration proved by elevated the contents of NADP(H), source, and fructose, as well as alleviated the levels of NAD(H). Cell membrane integrity was also better in these conditions, with higher activities of pyruvate kinase, phosphofructokinase b, and adenosine triphosphatase and lower activities of polyphenol oxidases and cytochrome C oxidases. Moreover, high CO2 decreased anaerobic respiration by inhibiting the accumulations of pyruvic acid, ethanol, and acetaldehyde, as well as by reducing the activities of pyruvate decarboxylase and alcohol dehydrogenase. Novelty impact statement: High CO2 (5% or 10%) enhanced the NAD(P)H levels in sweet cherries held at 0°C for 60 d.Respiratory metabolism was higher following the use of 10% CO2 during such storage.High CO2 maintained cell membrane integrity in sweet cherries stored at 0°C for 60 d. [ABSTRACT FROM AUTHOR]

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 log10CFU 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 (H2O2) 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 [ABSTRACT FROM AUTHOR]

In order to clarify an efficient and convenient method to increase the antioxidant activity in broccoli, this study intended primarily to elucidate the effect of cutting type on the quality parameters, antioxidant substance contents and antioxidant activity of broccoli using different floret diameters of 10 × 10 cm (CS1), 5 × 5 cm (CS2), 2.5 × 2.5 cm (CS3) and shredded florets (CS4). The results showed that chlorophyll, total soluble solid, vitamin C and reduced glutathione contents of fresh‐cut broccoli were decreased obviously during the storage. However, there was a significant influence of cutting type on the enzymatic activities involved in phenolic synthesis and oxidation including phenylalanine ammonia‐lyase, cinnamate 4‐hydroxylase, and polyphenol oxidase, which contributed to increasing phenolic content by 26.8%, 30.9%, 46.0%, and 51.3% in CS1, CS2, CS3 and CS4, respectively, and further enhanced the antioxidant activity by more than 60% in fresh‐cut broccoli. Moreover, the activities of antioxidant‐related enzymes, including superoxide dismutase, peroxidase and catalase, were increased significantly in fresh‐cut broccoli. In conclusion, the cutting types had no significant effect on quality but clearly influenced the antioxidant substances and activities of broccoli; therefore, this study provided an efficient and convenient method to enhance the potential nutritional value of broccoli. [ABSTRACT FROM AUTHOR]

Summary: In this study, the inhibition of an alginate‐based edible coating (EC) containing thyme oil (0.05%, 0.35% and 0.65%) was evaluated against Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus and Escherichia coli O157:H7 inoculated onto fresh‐cut apples. To investigate the antibacterial mechanism of thyme oil, the constituent compounds of that were analysed by gas chromatography‐mass spectrometry (GC‐MS), and the cellular damage of pathogens was observed by scanning electron microscopy (SEM). Results showed that alginate‐based EC containing thyme oil effectively inhibited the growth of pathogens on fresh‐cut apples. GC‐MS analysis revealed thymol (47.23%) as the major compounds in thyme oil. SEM showed that the cell membrane of foodborne pathogens was damaged by thyme oil, causing their inactivation. Treatment with alginate‐based EC containing 0.05% thyme oil preserved the sensory characteristics of fresh‐cut apples. Therefore, using alginate‐based EC with thyme oil may represent a potential approach to preserve and enhance the safety of fresh‐cut apples. [ABSTRACT FROM AUTHOR]

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 [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The effect of hydrogen sulfide (H2S) on the inhibition of the surface whitening of fresh‐cut carrots was investigated. Whitening index; H2O2 and malondialdehyde (MDA) contents; activities of catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD); and antioxidant capacities were evaluated. RESULTS: H2S treatment significantly inhibited the surface whitening of fresh‐cut carrots (P < 0.05), reduced the accumulation of H2O2 and MDA, and enhanced antioxidant enzymes (CAT, APX and GR) activities and antioxidant capacities (P < 0.05). The PAL, PPO and POD activities of fresh‐cut carrots were inhibited by treatment with H2S (P < 0.05). Furthermore, correlation analysis revealed that whitening index was significantly positively correlated with H2O2 content, lipid peroxidation, PPO and POD activities. CONCLUSION: H2S inhibited the surface whitening of fresh‐cut carrots by reducing H2O2 accumulation and lipid peroxidation, and also inhibited PPO and POD activities. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, the effects of oligochitosan treatment on controlling postharvest diseases in Dongxue peach (Prunus Persica L. Batsch, cv Dongxuemi) were examined and the possible underlying mechanisms were discussed. Results showed that the disease incidence and lesion area in peach fruit inoculated with Monilinia fructicola and Penicillium expansum were all remarkably reduced by oligochitosan treatment. Oligochitosan treatment inhibited spore germination and mycelial growth of the two fungi in vitro. Oligochitosan treatment also induced upregulation of the salicylic acid signalling pathway-related genes (NPR1, PR1 and phenylalanine ammonia lyase) and enhanced the levels of total phenolics, flavonoids and lignin in peach. Meanwhile, enzymatic activities of superoxide dismutase, catalase, polyphenoloxidase, ascorbate peroxidase and phenylalanine ammonia lyase also increased. These findings suggest that the effects of oligochitosan on the disease control of peach fruit may be associated with its direct antimicrobial effects as well as increasing antioxidant, phenylpropanoid metabolism and accumulating antifungal compounds by activating the salicylic acid-dependent pathway. [ABSTRACT FROM AUTHOR]

Fruit firmness is an important trait of postharvest blueberry, and ethanol vapor treatment has been shown to can retard blueberry softening by inhibiting the degradation of cell wall polysaccharides in our previous work. However, fruit softening is a complex process regulated by many factors. Here, the regulation mechanism of ethanol mediated delaying blueberry softening at the levels of mRNA and protein were explored with integrated transcriptomics-proteomics analysis. Results revealed that, 9158 differentially expressed genes (DEGs) and 1223 differentially expressed proteins (DEPs) were identified in the ethanol vapor-treated blueberry (E20) compared with the control (C20) at the 20th day of cold storage, 351 correlation molecules (DEG/DEP) were obtained through correlation analysis. Ethanol treatment reduced the overall metabolism level of blueberry, downregulated the gene expression of polygalacturonase, glucan-1,3- β -glucosidase and endoglucanase in carbohydrate metabolism pathway, and slowed down the degradation of cell wall polysaccharides such as pectin and cellulose; downregulated the gene expression of ACC oxidase, the key enzyme for ethylene synthesis, reduced the production of ethylene, reducing the ripening and softening effect of ethylene on the fruit, and then delayed the softening process of blueberry fruit. Collectively, ethanol vapor is a promising technology for retarding the softening of fruit and vegetables. • Ethanol vapor-treated blueberries maintained a higher level in firmness. • Ethanol vapor treatment regulated the carbohydrate metabolism of blueberry. • Ethanol vapor treatment regulated the carbon fixation in photosynthetic organisms. • Ethanol vapor treatment regulated ethylene synthesis. • Ethanol regulated MAPK signaling pathway-plant and plant-pathogen interaction. [ABSTRACT FROM AUTHOR]

Fresh-cut cantaloupe is particularly susceptible to contamination with pathogenic bacteria, such as Escherichia coli O157:H7, Listeria monocytogenes, and Staphylococcus aureus. Therefore, development of rapid, yet accurate detection techniques is necessary to ensure food safety. In this study, a multiplex PCR system and propidium monoazide (PMA) concentration were optimized to detect all viable pathogens in a single tube. A dual filtration system utilized a filtration membrane with different pore sizes to enrich pathogens found on fresh-cut cantaloupe. The results revealed that an optimized multiplex PCR system has the ability to effectively detect three pathogens in the same tube. The viable pathogens were simultaneously detected for PMA concentrations above 10 μg/ml. The combination of a nylon membrane (15 μm) and a micro pore filtration membrane (0.22 μm) formed the dual filtration system used to enrich pathogens. The achieved sensitivity of PMA-mPCR based on this dual filtration system was 2.6 × 103 cfu/g for L. monocytogenes, 4.3 × 10 cfu/g for E. coli O157:H7, and 3.1 × 102 cfu/g for S. aureus. Fresh-cut cantaloupe was inoculated with the three target pathogens using concentrations of 103, 102, 10, and 1 cfu/g. After 6-h of enrichment culture, assay sensitivity increased to 1 cfu/g for each of these pathogens. Thus, this technique represents an efficient and rapid detection tool for implementation on fresh-cut cantaloupe. [ABSTRACT FROM AUTHOR]

LAB are mostly used microorganisms for traditional fermented foods, e.g. Chinese northeast sauerkraut. However, the interactions between these strains are little known in mixed culture. This study aimed to explore the interaction between Leu. mesenteroides and L. plantarum based on metabolomics and transcriptomics during single- and mix-cultured fermentation of Chinese northeast sauerkraut. Metabolomics analysis revealed that the mixed culture showed different metabolite profiles in comparison with single culture. Higher levels of 4-vinylphenol (4.51%), 2,6-diaminopimelic acid (4.47%), ethyl dodecanoate (5.53%) were observed in mix-cultured samples than that with Leu. mesenteroides. In addition, the levels of 4-isopropylbenzoic acid (3.54%), 2,3-butanediol (7.23%), 1-octadecene (5.15%), ethyl dodecanoate (5.53%) were higher than that with L. plantarum. The most influenced pathway was carbohydrate metabolism, which was mostly related to 116 genes considered as DEGs in C_30 versus D_30 groups (CD), according to transcriptomics analysis. Additionally, 69 genes were considered as significantly DEGs in C_30 versus A_30 groups (CA) which were considerably mapped to amino acid metabolism. These results provided integrated views into the adaptive responses of the two strains to mix-cultured fermentation, which was useful for the rational development of mixed cultures in sauerkraut industry. • Sauerkraut was fermented by single and mixed cultures. • Metabolomic and transcriptomic elucidated interaction between Leu and Lpl. • Mix-cultured fermentation significantly affected the gene expression of Leu and Lpl. • Leu. mesenteroides mainly stimulated carbohydrates metabolism of L. plantarum. • Genes involved in amino acid metabolism of Leu were significantly upregulated by Lpl. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of 0.5% citric acid (CA), UV-C alone, and their combination (CA + UV) on native microflora survival, phenolic composition, browning, firmness and weight loss of fresh-cut ‘Fuji’ apples during refrigerated storage. Results showed that CA, UV alone and UV + CA had no significant effect on the firmness and total phenolic content but increased the polyphenol oxidase activity of fresh-cut apples. CA alone aggravated the browning and increased the weight loss of fresh-cut apples, while UV or UV + CA treatment significantly decreased the occurrence of browning reactions and reduced the weight loss as compared to control. The bacterial count of fresh-cut apples were reduced by 1.5, 2.1 and 2.6 log CFU/g after treatment with CA, UV and CA + UV, respectively. All these treatment retarded the microbial growth during storage and CA + UV treatment maintained the lowest growth rate among all treatment samples. Furthermore, the content of chlorogenic acid, (−) epicatechin, (+) catechin and caffeic acid in CA + UV treated sample was higher than the control after 15 d storage. Overall, these results suggest that CA + UV might be applied as an effective and safe preservative for fresh-cut apples. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the fate of Staphylococcus aureus, Listeria monocytogenes, and natural microbiota on fresh-cut tropical fruits (pitaya, mango, papaya and pineapple) with commercial PVC film at different storage temperature (5, 13, and 25 °C). The results showed that S. aureus, L. monocytogenes, and natural microbiota increased significantly on fresh-cut tropical fruits at 25 °C. Both pathogen and natural microbiota were able to grow on fresh-cut tropical fruits at 13 °C. The maximum population of L. monocytogenes was higher than that of S. aureus on fresh-cut tropical fruits. L. monocytogenes and S. aureus could survive without growth on fresh-cut pitaya, mango, and papaya at 5 °C. The population of L. monocytogenes declined significantly on fresh-cut pineapple at all temperature, indicating composition of fresh-cut pineapple could inhibit growth of L. monocytogenes. However, S. aureus was still able to grow on fresh-cut pineapple at storage temperature. Thus, this study suggests that 4 kinds of fresh-cut tropical fruits (pitaya, mango, papaya, and pineapple) should be stored at low temperature to extend shelf life as well as to ensure the safety of fresh-cut fruits. [ABSTRACT FROM AUTHOR]

Histidine decarboxylase (HDC) fromEnterobacter aerogenesDL-1 was purified in a three-step procedure involving ammonium sulfate precipitation, Sephadex G-100, and DEAE-Sepharose column chromatography. The partially purified enzyme showed a single protein band of 52.4 kD on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum pH for HDC activity was 6.5, and the enzyme was stable between pH 4 and 8.Enterobacter aerogenesHDC had optimal activity at 40°C and retained most of its activity between 4 and 50°C. HDC activity was reduced in the presence of numerous tested compounds. Particularly with SDS, it significantly (p < 0.01) inhibited enzyme activity. Conversely, Ca2+and Mn2+showed prominent activation effects (p < 0.01) with activity increasing to 117.20% and 123.42%, respectively. The Lineweaver–Burk plot showed thatKmandVmaxvalues of the enzyme for L-histidine were 0.21 mMand 71.39 µmol/min, respectively. In comparison with most HDCs from other microorganisms and animals, HDC fromE. aerogenesDL-1 displayed higher affinity and greater reaction velocity toward L-histidine. [ABSTRACT FROM PUBLISHER]

Abstract: The coating effects of tea polyphenol (TP) and rosemary extract (R) combined with chitosan (Ch) respectively on the quality of large yellow croaker (Pseudosciaena crocea) during refrigerated storage at (4 ± 1 °C) were evaluated. A solution of TP (0.2%, w/v) and R (0.2%, w/v) was used for dip pretreatment, and Ch (1.5%, w/v) was used for the coating. Microbiological (total viable count), physicochemical (pH, TVB-N, K value, PV, TBARS), and sensory attributes were periodically assessed over 20 days. The results indicated that the two dip pretreatments combined with chitosan coating could more effectively maintain the good quality and could extend the shelf life by 8–10 days compared with the control group during the refrigerated storage. [Copyright &y& Elsevier]

Abstract: The effect of coatings in combination with anti-browning agents (1%chitosan; 2%ascorbic acid+0.5%CaCl2 and 2% ascorbic acid +0.5%CaCl2 +1% chitosan) on minimally processed apple slices was studied during storage. Chitosan-coating treatments effectively retarded enzymatic browning on minimally processed apples during storage and they effectively retarded or avoided tissue softening, apple slices underwent a little loss of firmness. Chitosan-coating did not perform very well as water vapor barriers in apple slices. To control initial respiration rate of apple slices, edible coatings were applied to cut apples as semi-permeable barriers against air. Initial respiration rate showed a decrease in 2% ascorbic acid +0.5%CaCl2 +1% chitosan apple slices at 5°C. Industrial relevance: Recently, there has been an increasing market demand for minimally processed fruits and vegetables due to their fresh-like character, convenience, and human heath benefits. Minimal processing includes grading, washing, sorting, peeling, slicing, chopping, and then packaging. Since minimal processing results in quality deterioration associated with water loss, softening, microbial contamination, increased respiration and ethylene, and cut-surface browning, minimally processed products become more perishable. Edible coating was used for cut apples to reduced respiration and control physiological changes. The color of products, such as apple slices, is an important quality index. Brown apple slices are aesthetically unattractive. Chitosan has been reported to maintain the quality of fruit and vegetables (EI Ghaouth et al.,1991). The objective of this study was to develop procedures for the use of edible coatings in combination with anti-browning agent and to extend the shelf-life of minimally processed apple slices. [Copyright &y& Elsevier]

[Display omitted] • Sauerkraut was fermented by six mixed cultures made up with four LAB strains. • Mix-cultured groups had higher LAB population and lower number of spoilage bacteria. • The sensory properties were evaluated by E-tongue, E-nose and trained panelists. • Sauerkraut fermented with Leu. mesenteroides and L. plantarum showed the best quality. • The sensory characteristics of sauerkraut depended on the type of inoculant. Effects of mixed cultures composed of any two of four autochthonous lactic acid bacteria on fermentation of Chinese northeast sauerkraut were investigated in this study. Results indicated that different mixed cultures inoculation generated diversified physicochemical, microbiological and flavor quality of sauerkraut. Compared to spontaneous fermentation, mix-culture fermentation showed significant higher population of lactic acid bacteria and lower amounts of undesirable microorganisms. Free amino acids increased by 2- to 5-fold from initial level in spontaneous and mix-culture fermentation, with the lowest production by spontaneous fermentation. Moreover, mix-culture fermentation promoted the flavor formation based on the analysis of HS-SPME/GC-MS, E-nose, E-tongue and sensory evaluation, especially for the mixed culture of Leu. mesenteroides and L. plantarum. These results highlighted that using a mixed culture made up with Leu. mesenteroides and L. plantarum could be a potential way to improve the quality of sauerkraut, which could provide an alternative way to meet consumers' requirement. [ABSTRACT FROM AUTHOR]

[Display omitted] • Integrated proteomic and metabolomic analysis used in this study. • This study reveals the global proteins expression in wounded broccoli. • This work reveals the different DEPs between shreds and florets broccoli. • This work reveals the critical metabolic pathway responses to wounding in broccoli. The plant wound-response is a complex process that generates physiological modifications for protecting the wounded tissue. In this study, tandem mass tag (TMT)-based quantitative proteomic analysis was performed to clarify the comprehensive molecular mechanism for the wound-response of broccoli subjected to two wounding intensities (0.04 and 1.85 m2 kg−1 for florets and shreds, respectively). Furthermore, integrated proteomic and metabolomic analysis was performed to reveal the interaction among the critical metabolic pathway responses to wounding. The results show that a total of 399 proteins and 266 proteins were identified as differentially expressed proteins (DEPs) in florets and shreds broccoli compared to control, respectively. Furthermore, 167 DEPs were detected in shreds broccoli compared to the florets broccoli. Salicylic acid (SA) and ethylene (ET) biosynthesis were more susceptible to being induced by wounding with lower intensities, whereas, phenylpropanoid biosynthesis, aliphatic glucosinolate synthesis and jasmonic acid (JA) biosynthesis were more susceptible to being activated by wounding with higher intensities. The activation of starch and sucrose metabolism, TCA cycle, glycolysis, pentose phosphate could provide carbon sources and ATP for the production of amino acids including phenylalanine, valine, threonine, isoleucine, L -methionine, methionine and histidine. The motivation of carbohydrate metabolic pathways and amino acid biosynthesis-related pathways promotes the precursor levels for phenolic substances and glucosinolate synthesis. Furthermore, the accumulation of SA, ET and JA may activated secondary metabolite biosynthesis through the regulation of critical proteins involved in the corresponding metabolic pathways. [ABSTRACT FROM AUTHOR]

• Ethanol vapor delayed the decline in firmness of postharvest blueberries. • Ethanol vapor delayed degradation of cell wall polysaccharides in blueberry. • Ethanol vapor inhibited activities of cell wall-degrading enzymes in blueberry. • Ethanol vapor delayed the disruption of the cell wall structure of blueberry. Blueberry fruit were treated with 500 μL L−1 ethanol for 18 h and then stored at 0 ± 0.5 °C with 90 % relative humidity (RH) for 40 d. The firmness, contents of cell wall polysaccharides, activities of cell wall-degrading enzymes (CWDEs), and cell wall ultrastructure in the blueberry fruit were determined during storage. The results showed that the decline in firmness of blueberries was delayed by ethanol vapor treatment during cold storage and shelf life, compared to the control. The contents of water-soluble pectin (WSP) and 4 % KOH-soluble fraction (4KSF) in ethanol-treated blueberries were reduced compared to those in the control. The contents of EDTA-soluble pectin (ESP), Na 2 CO 3 -soluble pectin (SCSP), 24 % KOH-soluble fraction (24KSF), and cellulose in ethanol-treated blueberries were higher than the control. The activities of pectin methylesterase (PME), polygalacturonase (PG), carboxymethyl cellulase (CMCase), β -glucosidase (β -Glu), β -galactosidase (β -Gal), α -galactosidase (α -Gal), and α -mannosidase (α -Man) in blueberries were suppressed by ethanol vapor treatment. However, there was no significant difference in the activity of α -arabinofuranosidase (α -Af) between ethanol-treated blueberries and the control. Moreover, ethanol vapor treatment delayed the destruction of the cell wall structure of the blueberry fruit via ultrastructural observations. Ethanol vapor treatment can retard the disassembly of cell wall polysaccharides by inhibiting CWDEs activities, thereby delaying blueberry softening. [ABSTRACT FROM AUTHOR]

Oxidative stress significantly contributes to ageing and disease, with antioxidants holding promise in mitigating its effects. Functional foods rich in flavonoids offer a potential strategy to mitigate oxidative damage by free radicals. We investigated the protective effects of mulberry leaf flavonoids (MLF) against H2O2-induced oxidative damage in HepG2 cells. It assessed the inhibitory effect of MLF (62.5–500 μg/mL) on H2O2-induced oxidative damage by analyzing cellular morphology and oxidative stress markers, including ROS production, mitochondrial membrane potential, antioxidant enzyme levels, MDA, and apoptosis-related proteins. The results demonstrated that MLF prevented spiny cell formation triggered by 750 μM H2O2 and significantly reduced ROS levels, restored mitochondrial membrane potential, decreased lactate dehydrogenase and alanine transaminase leakage, and reduced MDA content induced by H2O2. MLF also modulated antioxidant enzymes and attenuated oxidative damage to HepG2 cell DNA, as confirmed by staining techniques. These findings indicate the potential of MLF as a hepatoprotective agent against oxidative damage in HepG2 cells. [ABSTRACT FROM AUTHOR]

A systematic phytochemical investigation of Pteris wallichiana J. Agardh resulted in the isolation of twenty compounds, including five sesquiterpenes (1 – 5), six flavonoids (6 – 11), seven phenolic acids (12 – 18) and two fatty acids (19 and 20). Their structures were deduced from MS, NMR and ORD data. This is the first report of compounds dehydropterosin B (2), (2 R ,3 S)-pterosin C (4), (2 R ,3 R)-pterosin L (5), apigenin (6), luteolin (7), luteolin-7- O -glucoside (10), caffeic acid (13), vanillin (14), 3,4-dihydroxybenzaldehyde (15), chlorogenic acid (17), 3,5-dicaffeoylquinic acid (18), suberic acid (19) and azelaic acid (20) from P. wallichiana and of compounds 15 , 19 and 20 from the family Pteridaceae. Furthermore, a chemotaxonomic study of the isolates was performed. • A phytochemical study of P. wallichiana led to isolation of twenty compounds. • Compounds 2 , 4 – 7 , 10 , 13 , 14 , 17 and 18 were first found from P. wallichiana. • Compounds 15 , 19 and 20 were first found from the family Pteridaceae. • P. wallichiana has a close chemotaxonomic relationship with other Pteris species. [ABSTRACT FROM AUTHOR]

• Metabolomics was used to explore the wounding-responsive mechanisms in broccoli. • Reveals the global metabolites levels in broccoli with different wounding intensities. • This investigation found that the purine metabolism induced by wounding in broccoli. • This study validated the plant hormone signaling induced by wounding in broccoli. • Validated that biosynthesis of secondary metabolites induced by wounding in broccoli. The mechanism of response of plant to wounding stress is a complex process that physiologically modifies the wounded tissue for protection. In this study, untargeted metabolomics and physiological analyses were performed to validate the molecular mechanism of response to wounding stress of two intensities (0.04 and 1.85 m2 kg−1) in broccoli florets and shreds, respectively. The results showed that 97 and 1220 differentially expressed metabolites could be identified in broccoli subjected to the Florets vs. Control and Shreds vs. Control experiments, respectively. The Kyoto Encyclopedia Genes and Genomes pathway analyses revealed that these metabolites were mainly involved in aminoacyl-tRNA, amino acid, and secondary metabolite biosynthesis; purine metabolism; and plant signal molecule production. This study validated that wounding stress induced plant signal molecule production. Activation of jasmonic acid biosynthesis and H 2 O 2 production were more susceptible to wounding stress of higher intensities, whereas induction of salicylic acid biosynthesis and O 2 − production were more susceptible to wounding stress of lower intensities. Furthermore, wounding stress also activated glucosinolate and phenylpropanoid biosynthesis by regulating the levels of the precursors, including L-leucine, phenylalanine, tyrosine, valine, isoleucine, tryptophan, methionine, and phenylalanine. Wounding stress induced phenylpropanoid biosynthesis and the antioxidant system by upregulating the corresponding critical enzyme activity and gene expression, contributing greatly to the enhancement of phenolic compound levels, free radical scavenging ability, and resistance to wounding in broccoli. [ABSTRACT FROM AUTHOR]

• Ultrasound-assisted extraction of phenolics from S. miltiorrhiza leaves was optimized. • An efficient procedure for purifying total phenolics by NKA-2 resin was developed. • Five major phenolics were identified and quantified by HPLC-DAD. • This study will enhance the potential exploitation of S. miltiorrhiza leaves. Salvia miltiorrhiza Bunge leaves, a crop waste, have potential as a source of bioactive phenolics. In this work, ultrasound-assisted extraction (UAE) was employed as a green extraction technology to extract phenolics from S. miltiorrhiza leaves. UAE parameters were optimized using response surface methodology (RSM) based on Box-Behnken design, achieving the total phenolics from S. miltiorrhiza leaves (SMLTP) yield of 71.16 ± 0.57 mg gallic acid equivalent per g of dry material (mg GAE/g DM) under optimal conditions. Afterwards, NKA-2 resin was selected to enrich SMLTP, the data for adsorption of SMLTP on NKA-2 resin fitted well with pseudo-second-order and Langmuir models. A NKA-2 resin-based chromatography procedure was optimized by studying breakthrough curves and desorption curves to enrich SMLTP from crude extract. A lab-scale enrichment experiment was performed under optimal conditions, the content of SMLTP in the product was 78.33 ± 0.61 %, which was 3.7 times higher than that in the crude extract, the recovery yield of SMLTP was 82.14 ± 1.62 %. Finally, HPLC-DAD analysis showed the contents of five major phenolic compounds including caffeic acid, rutin, isoquercitrin, rosmarinic acid, and salvianolic acid B significantly increased through enrichment. Certainly, this study will enhance S. miltiorrhiza industry to be more ecologic and economic. [ABSTRACT FROM AUTHOR]

• Cutting style has obvious influence on individual phenols content and antioxidant capacity in wounded broccoli. • Illuminate the critical genes expression involved in phenolics synthesis mechanism in wounded broccoli. • Cell antioxidant capacity of shredded broccoli increased by 86.5%. • Wounding stress might be applied as an effective way to get more antioxidants in industrial and domestic processing. To explore the effect of cutting style on the biosynthesis of phenolic compounds and cellular antioxidant capacity in wounded broccoli subjected to different cutting styles (heads, florets, 1/2 florets and shredded florets), the mechanism of the accumulation of phenolic compounds was investigated at the transcriptional level, and cellular antioxidant capacity was measured using a breast cancer cell MCF-7 culture model. The results indicated that the relative expression of the genes encoding phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase and 4-coumarin coenzyme A ligase, three enzymes involved in phenylpropanoid metabolism, was upregulated and that contributed to the synthesis of individual phenolic compounds, including catechin, hydroxybenzoic acid, chlorogenic acid, caffeic acid, sinapic acid, catechin gallate, rutin, cinnamic acid and quercetin. This research constructes the phenol synthesis pathway in wounded broccoli. Moreover, the relative expression of critical genes including superoxide dismutase, peroxidase, catalase, glutathione peroxidase and glutathione reductase involved in the metabolism of reactive oxygen species (ROS) increased, resulting in enhanced antioxidant capacity in wounded broccoli. Cell antioxidant capacity (CAA) of heads, florets, 1/2 florets and shredded florets increased by 52.7%, 59.2%, 64.8% and 86.5%, respectively, compared to whole broccoli. The enhancement of CAA was greater as the intensity of wounding increased, indicating that enhancement of antioxidant activity occurred at the cellular level. This research helps provide a reliable and persuasive theoretical basis for nutritional value assessment at the cellular level in wounded broccoli. [ABSTRACT FROM AUTHOR]

• Four LAB strains were selected from traditional northeast sauerkraut. • Sauerkraut was fermented with four LAB pure starter cultures. • Dynamic behavior of starter cultures was analyzed by qPCR. • Starters can be developed to customize fermented products for the consumer. The quality characteristics of sauerkraut fermented with autochthonous LAB selected from traditional northeast sauerkraut were investigated. The physicochemical, microbiological and metabolome were also determined. The pH decreased rapidly in inoculated sauerkraut along with high sugar utilization and acid production. qPCR analysis showed that inoculated products exhibited sufficient numbers of beneficial bacteria. PCA showed clear differences in volatilome profiles of sauerkraut depending on starter cultures used. The greatest abundance of esters (ethyl lactate, ethyl acetate and isoamyl acetate) was detected in L. plantarum -inoculated sauerkraut. Sauerkraut inoculated with L. paracasei had a significantly higher content of lactones. Leu. mesenteroides and W. cibaria inoculation contributed to an increase in acids and ketones. FAAs increased by 4.16-, 5.21-, 5.99-, 7.11- and 5.51-fold from the initial levels in spontaneous-, Leu. mesenteroides -, L. plantarum -, L. paracasei - and W. cibaria -fermented sauerkraut, respectively. Therefore, the physicochemical properties and aromatic quality of sauerkraut strongly depended on the starters used. [ABSTRACT FROM AUTHOR]

Phytochemical study of Pteris ensiformis Burm. resulted in the isolation of eleven compounds, including three sesquiterpenoids (1 – 3), one alkaloid (5), one amino acid (6), one flavonoid (7), four phenolic acids (4 , 8 , 9 and 10), and one coumarin (11). Structures of these compounds were deduced from the ESI-MS and NMR data. This is the first report on the isolation of compounds 1 , 2 , 7 and 11 from P. ensiformis , compounds 6 and 9 from the genus Pteris , and compound 5 from the family Pteridaceae. In addition, a detailed discussion of the chemotaxonomic significance of these compounds was presented. • P. ensiformis was found to contain various kinds of chemical constituents. • Four compounds including two pterosins, one flavonoid and one coumarin were first isolated from P. ensiformis. • L -phenylalanine and isoferulic acid were first isolated from the genus Pteris. • Nicotinamide was first isolated from the family Pteridaceae. • A close chemotaxonomic relationship between P. ensiformis and other Pteris species was found. [ABSTRACT FROM AUTHOR]

Phytochemical study on the roots of Sophora tonkinensis Gagnep. led to the isolation of fifteen compounds, including eleven flavonoids (1 – 11) and four phenolic acids (12 – 15). The structures of these compounds were elucidated based on NMR and HR-ESIMS analysis, further supported by comparison with previous literatures. Among them, compounds 2 , 3 , 4 , 6 , 9 , 12 and 13 were firstly discovered from S. tonkinensis , compound 8 was firstly discovered from the genus Sophora. Furthermore, the chemotaxonomic significance of the obtained compounds was discussed in detail. • Fifteen compounds were isolated from S. tonkinensis. • Compounds 2 , 3 , 4 , 6 , 9 , 12 and 13 were firstly reported in this species. • Compound 8 was firstly isolated from genus Sophora. • The chemotaxonomic significance of the isolates was discussed. [ABSTRACT FROM AUTHOR]

• Sauerkraut was fermented under four different salt concentrations. • Microbiota varied significantly among the different salted samples. • Salt had important effects on microbial growth and flavor formation. • A correlation between microbiota and flavor metabolites was observed. • 0.5% salt supported the growth of Lactobacillus and formed more flavor compounds. This study aimed to investigate the effects of salt concentration on the microbial community and flavor metabolites formed during northeast sauerkraut fermentation using a starter culture consisting of a combination Leuconostoc mesenteroides ORC 2 and Lactobacillus plantarum HBUAS 51041. The results revealed a correlation between microbiota and flavor metabolites, with the top 20 genera being identified using Illumina MiSeq. Lactobacillus and Leuconostoc were dominant genera throughout the fermentation process, and PCoA showed that the salt concentration had distinct impacts on the microbial community. The most abundant genus Lactobacillus (88.46%) was observed in the 0.5% salted sauerkraut at day 30. Forty-six flavor metabolites were identified by HS-SPME/GC–MS. The relative contents of esters, aldehydes and ketones showed the highest values in sauerkraut fermented with a 0.5% salt concentration. Sauerkraut fermented at 2.5 and 3.5% salt were characterized by higher relative contents of acids, alcohols, isothiocyanates and hydrocarbons. Spearman's rank correlation test results showed that Lactobacillus , Leuconostoc , Enterobacteriaceae , Pseudomonas , Staphylococcus and Bacillus were closely related to flavor metabolites. These results showed the effects of salt concentration on fermentation of northeast sauerkraut, revealing that sauerkraut fermented with 0.5% salt possessed a higher abundance of Lactobacillus and accumulated more flavor compounds (esters, aldehydes, ketones, nitriles and sulfides), providing a potential alternative approach to meet the preference of consumers for desirable aromatic quality. The results of this study may contribute to the industrial production of sauerkraut in Northeastern China. [ABSTRACT FROM AUTHOR]

• Adsorption was well fitted by the pseudo-second-order model and Langmuir model. • An efficient method for the enrichment of total flavonoids was developed. • Enrichment improved antioxidant and antiproliferative properties. The aim of this work is to develop an efficient and economical method for the enrichment of total flavonoids from Pteris ensiformis Burm. extracts. Resin screening, adsorption kinetics, adsorption isotherms and thermodynamics were successively researched prior to the dynamic adsorption and desorption tests. NKA-II resin was chosen as the best adsorbent, and the adsorption data were best described by the pseudo-second-order kinetics model and Langmuir isotherm model. The optimum enrichment conditions were as follows: for adsorption the total flavonoids concentration, flow rate and volume of sample were 1.84 mg/mL, 2 BV/h and 5 BV, respectively, and for desorption the flavonoids-loaded NKA-II resin column was desorbed by 7 BV of 50% ethanol at a rate of 2 BV/h. The product had a 6.63-fold higher total flavonoids content than crude extracts, and the recovery yield of total flavonoids was 80.65%. Furthermore, flavonoids-enriched extracts exhibited higher in vitro scavenging activity against superoxide anion radical and hydroxyl radical than crude extracts. In addition, higher antiproliferative activity of flavonoids-enriched extracts against MCF-7 and HepG-2 cell lines was also found as compared to the crude extracts. The developed method is appropriate for large-scale enrichment of total flavonoids from Pteris ensiformis Burm. extracts in the food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In this study, the antimicrobial mechanism of thyme essential oil (EO) against Listeria monocytogenes (LM) was investigated at the protein level using tandem mass tag-based quantitative proteomic analysis. The proteomic profiles of LM with 2 log CFU/ml reduction after thyme EO treatment (0.28 μl/ml, Treatment-1) were compared with those of 4 log CFU/ml reduction (0.31 μl/ml, Treatment-2) to identify key proteins involved in microbial inhibition. The results show that 100 and 745 differentially expressed proteins in LM subjected to Treatment-1 vs control and Treatment-2 vs control, respectively. The differentially expressed proteins were functionally categorized using gene ontology enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and STRING analyses. The differentially expressed proteins of LM in Treatment-1 vs control were involved in 45 biological processes, 18 cellular components, 48 molecular functions and 31 KEGG pathways. That of LM in Treatment-2 vs control were involved in 246 biological processes, 45 cellular components, 309 molecular functions and 86 KEGG pathways. It demonstrated that thyme EO treatment induced the cellular processes, environmental information processing, genetic information processing, human diseases, metabolism, organismal systems in LM according to the differently expression protein. Based on the known protein components of flagellar assembly and bacterial chemotaxis, the results suggest that treatment with thyme EO might inhibit flagellar synthesis, block the flagellar motility, and induce partial structural collapse in LM. The structure of flagella filament was damaged by thyme EO treatment. In addition, treatment with thyme EO might affect motility related to chemotaxis and adaptation in LM. This research contributes to the understanding of the molecular mechanisms underlying the inhibiting effects of thyme EO against foodborne pathogens and provide novel insights for further development of EO antimicrobial agents. Unlabelled Image • The antibacterial mechanism of thyme essential oil against L. monocytogenes involved six types of KEGG main class. • The structure of flagella filament on L. monocytogenes was damaged by thyme essential oil treatment. • Thyme essential oil treatment might inhibit flagellar synthesis and induce partial structural collapse in L. monocytogenes. • Thyme essential oil treatment might affect motility related to chemotaxis in L. monocytogenes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an ultrasonic-assisted procedure for the extraction of total phenolics from Citrus aurantium L. blossoms (CAB) and evaluate the free radical scavenging activity and anti-HMG-CoA reductase activity of the total phenolics. In this work, a Box– Behnken design based on single-factor experiments was used to explore the optimum extraction process. Under the optimum conditions (extraction solvent 70.31% ethanol, extraction temperature 61.94 °C, extraction time 51.73 min, and liquid-to-solid ratio 35.63 mL/g), the extraction yield of total phenolics was 95.84 mg gallic acid equivalents (GAE)/g dry matter (DM), which was highly consistent with the theoretical value (96.12 mg GAE/g DM). The higher contents of total phenolics and five main phenolic compounds obtained from the optimized ultrasonic-assisted extraction (UAE) proved its efficiency when compared with conventional heat reflux extraction (HRE). The total phenolic extract showed excellent free radical scavenging properties against 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·), 2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) radical (ABTS+·), hydroxyl radical (·OH) and superoxide anion radical (·O2−), with IC50 values of 197.007, 83.878, 218.643, and 158.885 μg/mL, respectively; the extracts also showed good inhibition of β-hydroxy-β-methylglutaryl-CoA reductase (HMG-CoA reductase) activity, with an IC50 value of 117.165 μg/mL. Total phenolics from CAB could be a potential source of natural free radical scavenger and HMG-CoA reductase inhibitor. [ABSTRACT FROM AUTHOR]

Presents an abstract of the article 'Study of the Optimal Values of d/t for MSFVW Delay Lines,' by Wenzhong Hu and Qingqing Huang.

Natural plant essential oils cannot be applied on a large scale due to their high volatility, easy deactivation, etc. This study provides a new method to prepare a long-lasting, slow-release essential oil product by taking advantage of solid lipid nanoparticles, which will provide a scientific guideline for the future essential oil industry. In this article, solid lipid cinnamaldehyde nanoparticles were prepared using an ultrahigh-pressure homogenization method. SLN-CA with a particle size of 74 ± 5 nm, PDI of 0.153 ± 0.032, and zeta potential of −44.36 ± 2.2 mV was screened using an additional amount of cinnamaldehyde, the ratio of oil phase components, and the homogenization pressure and number of times as factors. Differential thermal analysis and spectroscopy demonstrated that cinnamaldehyde was successfully encapsulated inside the nanoparticles. The change in particle size of nanoparticles under different conditions and times was used as an indicator of stability. The stability of the finished nanoparticles was evaluated. The retention and slow-release ability of cinnamaldehyde were investigated using the concentration of cinnamaldehyde in nanoparticles as an indicator. The results showed that after 15 days, SLN-CA retained 52.36% of the concentration from 15 days prior. The bacterial inhibition test shows that SLN-CA can inhibit bacteria [ABSTRACT FROM AUTHOR]

To evaluate the antioxidant activity of flavonoids extracted from Chinese herb mulberry leaves (ML), flavonoids from mulberry leaves (FML) were extracted and purified by using ultrasonic-assisted enzymatic extraction and D101 macroporous resin. Using LC-MS/MS-Liquid Chromatography with tandem mass spectrometry analysis, hesperidin, rutoside, hyperoside, cyanidin-3-o-glucoside, myricitrin, cyanidin, and quercetin were identified, and NMR and UV were consistent with the verification of IR flavonoid characteristics. The antioxidant activity of FML has also been evaluated as well as the protective effect on 2,2 0-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress. The results showed that FML exhibited powerful antioxidant activity. Moreover, FML showed dose-dependent protection against AAPH-induced sheep erythrocytes' oxidative hemolysis. In the enzymatic antioxidant system, pretreatment with high FML maintained the balance of SOD, CAT, and GSH-Px; in the non-enzymatic antioxidant system, the content of MDA can be effectively reduced after FML treatment. This study provides a research basis for the development of natural products from mulberry leaves. [ABSTRACT FROM AUTHOR]

Aqueous ozone was first used to take the place of chlorine as fresh-cut apples sanitiser. Aqueous ozone (1.4 mg L−1) treatments were evaluated for their effectiveness on microbial growth, quality attributes and shelf life of fresh-cut apples. The results indicated that aqueous ozone treatments for 5 and 10 min achieved accepted microbial quality and, respectively, reduced total bacteria counts by 1.83 and 2.13 log10 CFU g−1 compared with the control samples on the 12th day. The ethylene production, polyphenol oxidase and peroxidase activities, and total phenol and malondialdehyde contents were reduced by aqueous ozone treatments. In addition, this sanitiser also delayed the quality deterioration of fresh-cut apples and enhanced their antioxidant capacity. Therefore, it was recommended to sanitise fresh-cut apples with aqueous ozone (1.4 mg L−1) for 5 min, which applied to industrial production requirement for both efficiency and costs and could extend the shelf life up to 10 days. [ABSTRACT FROM AUTHOR]

Abstract: This study was devoted to the identification of proteins and specific peptides which could be used as indicators of freshness and quality in fish. The post mortem evolution of protein patterns in large yellow croaker muscle was monitored by SDS-PAGE and two-dimensional electrophoresis (2-DE) after cold storage for 0, 5, 10, 15, 20, 25 days. SDS-electrophoresis revealed the gradual degradation of protein bands of 16–17 kDa, 22–23 kDa, 35–36 kDa, 76–78 kDa, as well as the increase of protein bands of 32–34 kDa and 67 kDa. The analysis of 2-DE showed that five spots of interest, including 3 structural proteins, namely myosin heavy chain (MHC), LIM domain-binding protein 3 (LDB3) and troponin T, as well as 2 metabolic proteins α-enolase and glyceraldehyde 3-phosphate dehydrogenase, changed progressively, which could be used as the potential freshness markers of large yellow croaker. Further research is required to evaluate their expression and post mortem evolution in another fish species. [Copyright &y& Elsevier]

Abstract: This study was devoted to the identification of changes in microbiological, physicochemical and proteins which could be used as freshness indicators in large yellow croaker. The parameters that proved to be most sensitive to variations over storage time were total viable count, Shewanella putrefacents, Photobacterium phosphoreum, TVB-N, PV and K value. They might therefore be considered as good indicators for evaluating spoilage of large yellow croaker during refrigerated storage for 20 days. The proteins including MHC, actin, tropomyosin, protein bands of 14 ～ 15 kDa, 32 ～ 33 kDa, 35 ～ 36 kDa and 41 ～ 42 kDa could be used as the potential freshness markers of large yellow croaker. The results of these analyses indicated optimal quality for large yellow croaker stored under these conditions and established a shelf-life of 12 days. [Copyright &y& Elsevier]

• Ethanol fumigation maintained the postharvest quality of A. arguta fruit. • Ethanol vapor (250–500 μL L−1) reduced the superficial scald of A. arguta fruit. • Ethanol vapor increased the antioxidant capacity of A. arguta fruit. • Ethanol vapor treatment extended the optimum eating window by 14 d. Hardy kiwifruit (Actinidia arguta) stored at room temperature has a limited shelf life, and improper low-temperature storage can cause chilling injury. To address this issue, we applied ethanol vapor pre-treatment at concentrations of 250, 500, and 1000 μL L−1 and evaluated postharvest quality under low-temperature conditions (1 ± 1 °C). Our research revealed that lower concentrations of ethanol vapor (250–500 μL L−1) effectively mitigated chilling injury, delayed adverse physiological changes, such as superficial scald, softening, and rot, and enhanced the antioxidant system of A. arguta fruit. Ethanol treatment increased the activity of antioxidant enzymes like peroxidase, superoxide dismutase, and glutathione reductase while maintaining higher levels of non-enzymatic antioxidants like total phenolics, total flavonoids, ascorbic acid, and glutathione. It also improved the antioxidant capacity as assessed by various methods. Principal component analysis and overall scores demonstrated that ethanol vapor treatment significantly improved A. arguta fruit's antioxidant capacity and postharvest quality, extending the optimal consumption period by 14 d. This highlights ethanol's potential application in preserving A. arguta fruit's postharvest quality and enhancing its antioxidant capacity. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The present work was undertaken to examine the influence of grape seed extract (GS) and tea polyphenols (TP), as natural preservatives, combined with chitosan (Ch), on the quality of red drum (Sciaenops ocellatus) fillets during refrigerated storage. Two different treatments (Ch+GS and Ch+TP) and a control were prepared. The samples were stored (4±1°C) for 20days and the sampling was done at 0, 4, 8, 12, 16, 20days. Microbiological, physicochemical and sensory attributes were periodically assessed. The results indicated that the two pretreatments could more effectively maintain quality and could extend the shelf life by 6–8days compared with the control group during refrigerated storage. [Copyright &y& Elsevier]

Abstract: The effect of the natural preservatives, tea polyphenols and rosemary extract, on microbiological [total viable count (TVC)], chemical [pH, total volatile base nitrogen (TVB-N), K-value and thiobarbituric acid (TBA) values], texture and sensory changes of air-packaged whole crucian carp (Carassius auratus) stored at 4±1°C was investigated for 20days. The shelf-life of crucian carp was found to be 7–8days for untreated group (control), 13–14days for tea polyphenols group and 15–16days for rosemary extract treated group according to sensory assessment results, for which the corresponding microbiological assessment also showed an increased shelf-life. Meanwhile, the increases of pH, TVB-N, K-value and TBA values were significantly delayed in both treated groups of samples compared to the control group. Thus, either tea polyphenols or rosemary extract could be used as potential preservatives to extend the shelf-life of crucian carp during chilled storage. [Copyright &y& Elsevier]

In order to simulate the respiration rate of fresh produce during transport, retailing and storage, a respiration model for time and temperature dependence was developed. First, a model for time, based on the enzyme kinetics, was derived at a constant temperature. Next, temperature dependence of the model parameters was evaluated using an Arrhenius plot, and the model incorporating both temperature and time dependence was developed. To verify the model, the respiration rates of eggplant, asparagus, and broccoli were measured at changing temperatures (25 to 10 to 20 to 10 to 25 °C) with time. The results indicated that the model simulation was valid and the model was able to represent the respiration process. In other words, the predicted values by using this model agreed well with the experimental data. The model is expected to be available for rough estimation of sugar consumption during distribution. [Copyright &y& Elsevier]

The influence of aqueous ozone (1.4 mg/L) treatment for 1, 5, and 10 min on the microbial growth and quality attributes of fresh‐cut cabbage during storage at 4°C for 12 days was evaluated. The pesticide residue removal effect of aqueous ozone treatment for 5 min was also determined. The results show that the growth rates of aerobic bacteria, coliforms, and yeasts were significantly inhibited (p <.05) by aqueous ozone treatment during storage; treatment for 10 min showed the greatest inactivation of bacteria, coliforms, and molds. Aqueous ozone stimulated initial respiratory metabolism compared with that of the control. Aqueous ozone treatments reduced ethylene production and improved the overall quality of fresh‐cut cabbage. In addition, the effect of aqueous ozone treatment for 5 min on the removal of trichlorfon, chlorpyrifos, methomyl, dichlorvos, and omethoate from fresh‐cut cabbage was greater (p <.05) than that of the control. These results indicate that aqueous ozone treatment for 5 min could be an economic and effective method to remove pesticide residues and enhance the storability of fresh‐cut cabbage. [ABSTRACT FROM AUTHOR]

The native microflora survival and quality retention of fresh-cut onions treated by ozonated water (OW) with ozone concentration of 1.4 mg L−1, for 1, 3, and 5 min during storage at 4°C for 14 days were investigated. The pesticide residue removal effect of OW treatment for 5 min was also determined. The results show that all OW treatments significantly inhibited the growth of aerobic bacteria, coliforms, and yeasts during storage, with the OW treatment for 5 min allowing the lowest growth rates. OW treatment for 1 min significantly reduced the weight loss of fresh-cut onions during a longer storage time (8–14 d). All OW treatments reduced the respiration rate and the softening of fresh-cut onions, exhibiting better overall quality retention than the control samples. In addition, OW treatment for 5 min significantly reduced the residual levels of five tested pesticides (dimethyl dichlorovinyl phosphate, cypermethrin, chlorpyrifos, methomyl, and omethoate) compared with water treatment. These results indicate that treatment with OW is a promising strategy to control the microbial growth, preserve the quality and reduce pesticide residual of fresh-cut onions. OW: ozonated water; PCA: plate count agar; VRBA: violet red bile agar; PDA: potato dextrose agar; DDVP: dimethyl dichlorovinyl phosphate [ABSTRACT FROM AUTHOR]

The widespread use of caffeine in food and drug industries has caused great environmental pollution. Herein, an efficient caffeine-degrading strain Paraburkholderia caffeinilytica CF1 isolated from a tea garden in China can utilize caffeine as its sole carbon and nitrogen source. Combination of chromatographic and spectrophotometric techniques confirmed that strain CF1 adopts N-demethylation pathway for caffeine degradation. Whole genome sequencing of strain CF1 reveals that it has two chromosomes with sizes 3.62 Mb and 4.53 Mb, and a 174-kb mega-plasmid. The plasmid P1 specifically harbors the genes essential for caffeine metabolism. By analyzing the sequence alignment and quantitative real-time PCR data, the redundant gene cluster of caffeine degradation was elucidated. Genes related to catalyzing the N1-demethylation of caffeine to theobromine, the first step of caffeine degradation were heterologously expressed, and methylxanthine N1-demethylase was purified and characterized. Above all, this study systematically unravels the molecular mechanism of caffeine degradation by Paraburkholderia. Key Points: • Caffeine degradation cluster in Paraburkholderia caffeinilytica CF1 was located in mega-plasmid P1. • The whole genome and the caffeine degrading pathway of P. caffeinilytica CF1 were sequenced and elucidated, respectively. • This study succeeded in heterologous expression of methylxanthine N1-demethylase (CdnA) and Rieske oxygenase reductase (CdnD) and illuminated the roles of CdnA and CdnD in caffeine degradation of P. caffeinilytica CF1. [ABSTRACT FROM AUTHOR]

Herein, we examined the effects of plasma-activated water (PAW) treatment on the native microflora survival, quality maintenance, and antioxidant activity of fresh-cut pears, which were washed with PAW under three different conditions (peak voltage = 6, 8, and 10 kV) for 5 min and then stored at 4 °C for 12 days. Distilled water and sodium hypochlorite treatment were used as control and comparison, respectively. Results showed that all PAW treatments significantly inhibited the growth of aerobic bacteria, yeast, and mold during storage, with the 8-kV PAW treatment maintaining the lowest growth rate. Additionally, no significant change was observed in the soluble solid content and titratable acidy of fresh-cut pears treated with PAW. Treatment by 6-kV PAW significantly slowed down the softening of fresh-cut pears, while the 8-kV PAW treatment significantly reduced the mass loss and the total phenolic content (P < 0.05). The ascorbic acid content and radical scavenging activity (DPPH and ABTS) of fresh-cut pears were affected by PAW treatment only at the beginning of storage. After 8 days of storage, no significant differences were found in ascorbic acid content and radical scavenging activity among the samples (P > 0.05). Furthermore, PAW outperformed sodium hypochlorite in antimicrobial effectiveness and quality maintenance. Taken together, these results suggest that PAW treatment might be a promising strategy to control microbial growth and maintain the quality of fresh-cut pears. [ABSTRACT FROM AUTHOR]

Highlights • LED maintained the quality and delayed the senescence of broccoli stored at 20 °C. • Yellowing, weight loss, and MDA accumulation were inhibited by LED. • LED induced the antioxidant enzyme activity in stored broccoli. • Expression of chlorophyll-degrading genes in broccoli was suppressed by LED. Abstract The quality of broccoli stored at ambient temperatures deteriorates rapidly as tissues begin to senesce. The effect of red light-emitting-diode (LED) light irradiation (50 μmol m−2 s−1) on the quality of harvested broccoli stored at 20 °C for 5 d was investigated. Sensory quality and physiological function, including the activity of antioxidant enzymes and the expression of genes associated with chlorophyll degradation, were analyzed. Results indicated that red LED irradiation maintained the sensory appearance of broccoli, inhibited yellowing and the degradation of chlorophyll, and decreased weight loss and malondialdehyde (MDA) content. The activity of the antioxidant enzymes, peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were enhanced in LED-treated broccoli, while the expression of the chlorophyll degrading genes, chlorophyllase Ⅱ (BoCLH2), chlorophyllase Ⅲ (BoCLH3), and pheophorbide a oxygenase (BoPAO) was suppressed in the early stages of storage. In contrast, no effect on chlorophyllase Ⅰ (BoCLH1) was observed. These results demonstrated that irradiation of broccoli with red LED induced a series of physiological and molecular responses that extended postharvest quality and could be used to prolong the shelf-life of commercially produced broccoli. [ABSTRACT FROM AUTHOR]

Highlights • Putrescine inhibited the postharvest yellowing of broccoli stored at 20 °C in dark. • Putrescine reduced chlorophyll degradation. • The expressions of BoCLH2 , BoPAO and BoPPH were reduced by putrescine. • Gene expression and activity of antioxidant enzymes were induced by putrescine. Abstract Broccoli undergoes yellowing very quickly in storage, which impacts its' quality and economic value. The current study examined the ability of putrescine to inhibit postharvest yellowing of broccoli florets. Broccoli heads were dipped in a 0.25 mmol L−1 solution of putrescine for 10 min, air dried, and then stored at 20 °C in the dark. Results indicated that, relative to the untreated control, putrescine treatment effectively suppressed changes in fruit color from green to yellow, reduced the degradation of chlorophyll, decreased electrolyte leakage, inhibited the accumulation of malondialdehyde, and maintained the enzyme activity and gene expression of peroxidase, catalase, and ascorbate peroxidase. The relative expression of chlorophyllase Ⅰ (BoCLH1) and chlorophyllase Ⅲ (BoCLH3) was enhanced while the relative expression of chlorophyllase Ⅱ (BoCLH2), pheophorbide a oxygenase (BoPAO), and pheophytinase (BoPPH) was reduced by putrescine. The data clearly indicate that putrescine reduces the yellowing of broccoli florets and may represent an effective approach for reducing postharvest losses in broccoli. [ABSTRACT FROM AUTHOR]

Yeast diversity and dynamics associated with the spontaneous fermentation of Vidal blanc icewine was investigated in icewine from the Huanren region of China. This knowledge is crucial to control fermentation and to screen for indigenous strains capable of producing icewines with regional characteristics. Laboratory-scale spontaneous fermentation was performed to monitor wine yeasts involved in the fermentation. Samples were collected from different stages of the fermentation and analyzed using culture-dependent (Wallerstein laboratory nutrient agar) and -independent methods (high-throughput sequencing, HTS). Two hundred eight yeast strains were isolated and identified by sequencing the internal transcribed spacer (ITS) region and the 26S rDNA D1/D2 domain genes; non- Saccharomyces yeasts were predominant in the initial stages, while Saccharomyces yeasts dominated in the final stages of the fermentation. Analysis of the HTS data of the ITS1 region gene revealed a more complex mycobiota. The wine yeast species found by HTS were more abundant than those found by cultivation; non- Saccharomyces yeasts were dominant initially, while Metschnikowia and Saccharomyces were predominant in the end. These results were not completely in agreement with the results obtained by using the cultivation-based method. Moreover, HTS revealed the presence of Mrakiella and Mrakia , which have never been reported in icewine before. [ABSTRACT FROM AUTHOR]