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Banana is a tropical fruit widely accepted by people over the world. Its chemical composition is critical for its organoleptic properties and nutritional value. In this work, the metabolite changes during postharvest senescence were investigated using NMR spectroscopy. The 1D and 2D NMR spectroscopic information revealed the primary and secondary metabolites in banana fruit, including organic acids, amino acids, carbohydrates and phenolics. Bananas at five senescence stages showed similar chemical profiles, but the levels of the individual compounds varied to a large extent. The principal metabolites responsible for postharvest senescence of banana were valine, alanine, aspartic acid, choline, acetate, glucose, malic acid, gallic acid and dopamine. At stage V, ethanol was present due to the conversion of glucose. Salsolinol was generated due to the conversion of dopamine. This was a characteristic marker for the postharvest senescence of banana fruit.

Mandarin (Citrus reticulata), a non-climacteric fruit, is an economically important fruit worldwide. The mechanism underlying senescence of non-climacteric fruit is poorly understood. In this study, a gel-based proteomic study followed by LC-ESI-MS/MS analysis was carried out to investigate the proteomic changes involved in peel senescence in harvested mandarin "Shatangju" fruit stored for 18 days. Over the course of the storage period, the fruit gradually senesced, accompanied by a decreased respiration rate and increased chlorophyll degradation and disruption of membrane integrity. Sixty-three proteins spots that showed significant differences in abundance were identified. The up-regulated proteins were mainly associated with cell wall degradation, lipid degradation, protein degradation, senescence-related transcription factors, and transcription-related proteins. In contrast, most proteins associated with ATP synthesis and scavenging of reactive oxygen species were significantly down-regulated during peel senescence. Three thioredoxin proteins and three Ca(2+) signaling-related proteins were significantly up-regulated during peel senescence. It is suggested that mandarin peel senescence is associated with energy supply efficiency, decreased antioxidant capability, and increased protein and lipid degradation. In addition, activation of Ca(2+) signaling and transcription factors might be involved in cell wall degradation and primary or secondary metabolism.

Al 2 O 3 /TiO 2 nanostructured ceramic composite coatings were prepared on 6063 aluminum alloy substrates by plasma spraying in this paper. The microstructure and properties such as micro-hardness, wear resistance and corrosion resistance were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness tester, frictional wear testing machine and salt spray test. The results showed that both α -Al 2 O 3 and γ -Al 2 O 3 phases exist in the as-sprayed nanostructured ceramic composite coatings, and the content of γ -Al 2 O 3 phase increases with increasing the spraying power, while rutile TiO 2 phase exists in the coatings. The as-sprayed coatings were composed of bimodal structure, i.e., completely melted lamellar and partially melted particulate structure. Effects of both plasma spraying power and TiO 2 content on hardness and wear resistance as well as corrosion resistance of the as-sprayed coatings were obvious.

Devil’s club (Oplopanax horridus (Sm.) Miq.) has traditionally been used as a folk medicine by native North Americans for the treatment of various chronic diseases. A methanolic extract and its sub-fractions by liquid–liquid re-extraction, i.e., chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (BuOH), and water fractions, were analysed by their anti-cancer activity with in vitro cell proliferative bioassays, and their antioxidant capacities in terms of the determination of total phenolic content (TPC), ORAC value, and DPPH free radical scavenging activity. The whole extract of the dried root contained high TPC and possessed strong ORAC and DPPH radical scavenging activities. In addition, the extract exhibited a strong anti-proliferative ability against HT-29 cancer cells, e.g., with an inhibitive rate of 56.5% with a 0.2-mg/mL extract. Further investigation by HPLC–UV–MS identified significant bioactive phenolic compounds in the chloroform fraction, including gallic acid, caffeic acid, 4-O-feruloylquinic acid, 5-O-feruloylquinic acid, ferulic acid, methyl feruloylquinate, methyl ferulate, and quercetin. These results suggested that the associated bioactivity of the plant might result from the contribution of phenolic compounds.

Banana and broccoli are two major fruits in tropics and subtropics areas. It is of great value to treat them for shelf life delaying and to improve commercial value. The fresh harvested banana and broccoli were treated with forchlorfenuron (CPPU) and gibberellic acid (GA3) in different concentrations respectively, and then stored at 25 ± 2 °C, 75–95%RH after air dry. Changes of peel color, flesh firmness, fruit respiration rate, brown and fungal incidence were investigated during the storage. The results showed that, as compared with the control fruits, 10 mg l−1 CPPU with different concentrations of GA3 had good effect on the fruit and vegetable. Especially in the group treated with 10 mg l−1 CPPU + 50 mg l−1 GA3, surface color change was obviously retarded, fruit respiration rate was inhibited, and the natural browning was significantly inhibited as well. In addition, the accumulation of soluble sugars in the fruit was reduced, and the water loss rate (4.55 ± 0.04%) was also inhibited. These treatments not only can delay maturing and softening of banana and broccoli, but also can maintain the color and resist the fungal infection to extend the shelf life.

With-leaf (WL) storage and selling are becoming increasingly popular with consumers for its attractiveness and freshness. To better understand the changes of quality attributes in fruit stored WL, quality, antioxidant properties and volatile in “Shatangju” mandarin were determined during the 9-week storage at 5C. WL storage decreased titratable acidity, flavonoid content and antioxidant activity determined by 1-diphenyl-2-picrylhydrazyl but increased ethanol content significantly, whereas WL storage had no significant effects on the content of total soluble solids, acetaldehyde and total phenolics, and reducing power. Furthermore, WL storage decreased the diversity of volatile compounds quickly. Based on the study, “Shatangju” mandarin fruit WL (packed with polyethylene film and fungicide-treated) could be stored at 5C for up to 7 weeks. To the best of our knowledge, this is the first study thoroughly describing the quality profile of fruit stored WL. PRACTICAL APPLICATIONS This paper reports on the changes of quality, antioxidant activity and volatile compositions of “Shatangju” mandarin fruit stored with leaves (WLs) attached to the remaining pedicle at a temperature commonly encountered in the industry. From the results obtained, “Shatangju” mandarin stored WL deteriorates much quicker than without leaf because of faster accumulation of acetaldehyde and ethanol, and decrease in total soluble solids, titratable acidity, total phenolics, flavonoids, 1-diphenyl-2-picrylhydrazyl radical scavenging activity, reducing power and the volatile components. The results of the study suggest that a storage life of 7 weeks at 5C is recommended for commercial usage.

The effects of short-term anoxia pre-treatment on browning of fresh-cut Chinese water chestnut (CWC), stored at 4 °C, in relation to antioxidant activity were investigated. CWC slices were exposed to pure N2 for 4 h and then stored at 4 °C for 18 d. Anoxia significantly inhibited browning of CWC slices during storage, accompanied by lower contents of malondialdehyde, H2O2, and lipoxygenase activity. Furthermore, anoxia induced the activities of superoxide dismutase and ascorbate peroxidase, which could benefit scavenging reactive oxygen species and alleviating lipid peroxidation. In addition, better maintenance of reducing power and free-radical-scavenging activities against α,α-diphenyl-β-picrylhydrazy (DPPH), superoxide anions and hydroxyl was observed in N2-treated CWC slices, with higher phenolic compounds and ascorbic acid contents. Collectively, these finds suggest that N2 pre-treatment enhanced enzymatic and non-enzymatic antioxidant activity in CWC slices, and thereby contributed to alleviating lipid peroxidation and maintenance of storage quality.

Experiments were conducted to investigate the effects of 1-methylcyclopropene (1-MCP) on chilling injury disorders and quality maintenance of harvested okra ( Hibiscus esculentus L.) fruit during storage at low temperature. Okra fruit were treated with 1 or 5 μl L −1 1-MCP for 16 h before storage for 18 d at 7 °C. Application of 1-MCP significantly alleviated the development of chilling injury disorders such as browning and pitting in okra pods in a concentration-dependent pattern, which was associated with lower membrane permeability and lipid peroxidation. In addition, 1-MCP treatment inhibited the decreases in color parameters (hue angle, lightness and chroma) and chlorophyll degradation, indicating that the bright green color in 1-MCP-treated fruit was well maintained. Furthermore, 1-MCP reduced the chilling-induced decline in variable:maximal chlorophyll fluorescence ( F v / F m ), an indicator of stress injury in plant tissues. Moreover, significantly lower respiration rate in 1-MCP-treated okra was also observed than in control fruit. Overall, 1-MCP treatment showed great potential to reduce the development of chilling injury disorders and maintain fruit quality, which may be a promising technique to extend the storage life of okra pods at low temperature.

The effects of 1-methylcyclopropene (1-MCP) on leaf senescence and fruit quality in “Shatangju” mandarin fruit with attached leaves were investigated. Fruit with attached leaves were treated without or with 5 μl L−1 1-MCP for 16 h before storage for 20 d at 20 °C. Application of 1-MCP inhibited leaf abscission, chlorophyll degradation, and the decrease in the ratio of variable to maximal chlorophyll fluorescence (Fv/Fm). However, no significant differences in ascorbic acid and titratable acidity contents, or α,α-diphenyl-β-picrylhydrazy radical scavenging activity of flesh were observed between control and 1-MCP-treated fruit with leaves after 20 d in storage. Moreover, treatment with 1-MCP had no effect on respiration and de-greening of fruit, except after day 10 for the respiration rate. Overall, these findings suggest that treatment with 1-MCP inhibited leaf abscission and senescence, but did not influence fruit quality. This may be a promising technique to extend the shelf-life of “Shatangju” mandarins with attached leaves.

An expansin gene, MiExpA1 , from mango fruit ( Mangifera indica L. cv. Zill), which had highest homology with MiExpA1 from cv. Dashehari by 96.43% in nucleotide sequence and 95.79% in amino acid sequence, was cloned and characterised. Moreover, effects of oxalic acid on MiExpA1 expression and enzymatic activities of α -galactosidase ( α -Gal), β -galactosidase ( β -Gal), and polygalacturonase (PG) were investigated after Zill fruit were dipped in 5 mM oxalic acid solution for 10 min and then stored at 25 °C. Application of oxalic acid significantly inhibited decrease in flesh firmness, notably suppressed and delayed MiExpA1 expression in the peel and the flesh, and also significantly decreased activities of these pectolytic enzymes in the flesh. It was suggested that these effects of oxalic acid might collectively contribute to alleviating cell wall disassembly, thereby slowing the process of softening and ripening in mango fruit during storage.

A multi-analytes method for monitoring of organophosphorus pesticides (OPs) using a combination of broad-specificity direct competitive enzyme-linked immunosorbent assay (dcELISA) and high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) was developed. The reaction formats of dcELISA as well as the matrix effects of vegetable samples by different treatments were studied. The dcELSIA based on horseradish peroxidase-labelled monoclonal antibody and solid-phase extraction can analyse 42 samples in duplicate simultaneously for 12 OPs with a limit of detection at 20 μg L −1 within 40 min, with good accuracy and reproducibility. For screening purpose, the dcELISA can distinguish positive samples from hundreds of negative samples at a rapid, high-throughput and low cost manner. The positive samples can be following confirmed by HPLC–MS/MS for the kinds and the relative amounts of OPs. The method is suitable for monitoring of OP contamination in vegetables samples with high-efficiency and low cost.

Inhibitory mode and anti-diabetic activities of the Carols muscadine extracts on the α-glucosidase and pancreatic lipase were investigated. The IC 50 values of the muscadine and its seed methanolic extracts against the α-glucosidase were 1.92 and 1.53 mg/mL, and those against the lipase were 34.41 and 8.63 mg/mL, respectively, which indicated the muscadine possessed the strong anti-diabetes activity. Particularly, the ethyl acetate (EtOAc) extract fractions exhibited the highest inhibitory activities against both enzymes. Since most of the phenolic compounds existed in the EtOAc fractions, it is suggested that phenolic compounds may be the main source against the α-glucosidase and pancreatic lipase. Twelve individual phenolics were identified by HPLC-MS. Ellagic acid and quercetin exhibited much stronger anti-diabetic activities among the selected phenolic standards. Besides, the extracts and the phenolic standards obeyed the competitive mode in their enzymatic inhibitions.

In this work, quercetin, p -courmaric acid and their derivatives were chosen to evaluate the prooxidant activity in NADPH/peroxidase/H 2 O 2 and DNA cleavage systems. The balance between antioxidant and prooxidant effect was not apparent. The number of hydroxyl groups, hydrophilicity, steric hindrance, concentration and affinity to peroxidase were critical for the prooxidation behaviour of tested compounds. Ortho -methoxy substitution led to a decreased prooxidant activity for p -courmaric acid. The DNA cleavage activity was in a decreasing order, quercetin = rutin > p -courmaric acid > ferulic acid > quercetin 3-O-glucoside. By calculation of Δ E (LUMO−HOMO) and ΔHOF, the reactivity of forming phenoxyl radicals was quercetin > rutin > quercetin 3-O-glucoside, which was in agreement with their DNA cleavage activities. The prooxidant activity order of p -courmaric acid and ferulic acid was in contrast to their reactivities of forming phenoxyl radical. The log P difference should play a critical role in the prooxidation behaviour.

Pericarp browning and decline in quality are the major postharvest problems of litchi fruit (Litchi chinensis Sonn.) during storage and transportation. Experiments were conducted to investigate the effects of ultrasonic treatment on pericarp browning and quality of harvested litchi fruit. Fresh fruits of litchi cv. Guiwei were treated with ultrasonic at power of 0 (control) or 120 W for 10 min in water and then stored at room temperature (28C). Application of ultrasonic generally reduced the degradation of litchi anthocyanins and increase in relative leakage rate throughout the storage period, and inhibited the activities of polyphenol oxidase and peroxidase at the early storage stage and, thus, significantly delayed pericarp browning of litchi fruit. However, ultrasonic treatment accelerated the reduction in the amount of total soluble solids and slowed down the increase in total titratable acid. All these results suggest that the application of ultrasonic can effectively control the pericarp browning of postharvest litchi fruit during storage. PRACTICAL APPLICATIONS Litchi fruit has a very short storage life under ambient conditions because of the browning and quality deterioration. Various approaches are now applied to extend the storage life of litchi fruit, such as sulfur fumigation, chitosan coating and acidic treatment. Although sulfur treatment has been adopted widely, sulfur residue remains to be solved. Therefore, a novel postharvest technique ultrasonic sound without hazard to human health is needed urgently. In this study, ultrasonic treatment was used to effectively delay the pericarp browning of harvested litchi fruit. This prospective technique will be helpful to solve the problem of litchi browning from another angle and substitute the chemical approaches of antibrowning to prolong the storage life and control the decay of litchi.

Litchi (Litchi chinensis Sonn.) is a subtropical fruit of high commercial value in international trade. However, litchi fruit after harvest can rapidly lose their bright red skin color and turn brown with increasing storage time at ambient temperature. Postharvest browning of litchi fruit is mainly attributed to the degradation of anthocyanins and the oxidation of phenolics. In this study, the contents of lipofuscin-like substance in relation to the levels of anthocyanins and (-)- epicatechin, and browning index of litchi fruit during storage were investigated. In a storage period from 72 to 144 h, the relative content of lipofuscin-like substance increased by 51.1% while the contents of (-)-epicatechin and anthocyanins decreased by 41.2 and 98.1%, respectively, and the obvious accumulation of lipofuscin-like substance of pericarp tissue of litchi fruit was related to the reduced contents of anthocyanins and (-)-epicatechin. Furthermore, the increase in the con- tent of lipofuscin-like substance was significantly related to the increased browning index. It is suggested that lipofuscin- like substance could be one of the final products from the browning reaction of litchi fruit during storage.

Peach kernel oil was extracted using Soxhlet extraction with different solvents (petroleum ether, ethyl ether, chloroform and hexane). The physicochemical properties (acid value, iodine value, peroxide value and saponification value), the fatty acid composition, phenolic constituents and contents, and antioxidant activities of peach kernel oil were examined. As per our results, oil extracted with hexane has better overall quality. Its acid, peroxide, iodine and saponification values were 0.895 mg KOH/g oil, 0.916 mg/g oil, 36.328 mg/100 g oil and 101.836 mg KOH/g oil, respectively. Large proportions of unsaturated fatty acid (91.27%) and high content of phenolic compounds (4.1593 mg GAE/g), which contribute to considerably strong antioxidant activity, were found in oil. The main fatty acids found in the peach kernel oil were oleic acid (61.87 g/100 g oil) and linoleic acid (29.07 g/100 g oil). The HPLC analysis of phenolic compounds showed that rutin, (-)-epicatechin gallate, hydrocinnamic acid, sinopinic acid, dithiothreitol and caffeic acid were major constituents. The results suggested that peach kernel oil is a good source of the unsaturated fatty acid, phenolic compounds with strong antioxidant activity, and has the potential to be used as nutrient rich food oil. The results also verified that peach kernel meals contained higher amounts of total phenolic and stronger antioxidant activities than oils, enabling their application as ingredients for functional or enriched foods.

Fusarium proliferatum was isolated as a major pathogen causing the Fusarium disease in harvested banana fruit. One of its major compounds, fusaric acid, was identified by high-performance liquid chromatography–electrospray ionization mass spectrometry (HPLC–ESI–MS). Because the light intensity of the luminescent bacterium Vibrio qinghaiensis sp. Nov. Q67 can be inhibited by fusaric acid, the fusaric acid content of F. proliferatum was assessed and compared by both the HPLC and luminescent bacterium methods. Although both methods afforded almost similar values of fusaric acid, the latter indicated slightly lower content than the former. Czapek medium was more suitable for the growth of F. proliferatum and fusaric acid production than modified Richard medium, with an optimum pH of approximately 7.0. However, no significant (P < 0.05) correlation was obtained between the fusaric acid production and growth of mycelia of F. proliferatum. The study suggests that the bioevaluation by use of the luminescent bacterium was effective in monitoring fusaric acid production by F. proliferatum without expensive equipment.

Peanut protein isolate (PPI) was extracted by high-pressure homogenization (HPH) under 0.1 MPa (atmospheric pressure) and 40 or 80 MPa (high pressure). Effects of Alcalase (a proteolytic enzyme) on the enzymatic hydrolysis of PPI and the antioxidant activity of the PPI hydrolysates were investigated. The molecular weight distributions of the PPI hydrolysates were analyzed using Sephadex G-25 gel filtration chromatography while the antioxidant activities, including reducing power, 1,1-dipheny-2-picrylhydrazyl (DPPH) radical-scavenging activity and hydroxyl free radical-scavenging activity of the PPI hydrolysates were evaluated. The extraction yields of PPI by HPH under 0.1, 40 and 80 MPa were 16.84, 30.65 and 39.86%, respectively, which showed that HPH treatment improved the PPI extraction. The HPH treatment increased the degree of hydrolysis of PPI and significantly increased the reducing power and hydroxyl radical­scavenging activity. Furthermore, the molecular weight distributions of the PPI hydrolysates appeared principally over the range of 1000–5000 Da, while the HPH treatment enhanced the production of small peptides, which was in agreement with the high PPI hydrolysis degree. These results suggest that HPH treatment in combination with enzymatic hydrolysis could modify PPI properties and increase the antioxidant activities of the PPI hydrolysates. Industrial relevance This study was focused to evaluate the effects of high-pressure homogenization (HPH) in combination with enzymatic hydrolysis on extraction yield and enzymatic hydrolysis of PPI and antioxidant activity of the PPI hydrolysates. This study indicated the possibility of improving the availability of PPI by HPH treatment via increasing extraction yield and enzymatic hydrolysis of the PPI, which can provide a better utilization of the peanut by-product.

The effects of reactive oxygen species (ROS), especially hydroxyl radical (OH), on cellular wall disassembly in vitro and in vivo, and aril breakdown in longan fruit, were investigated. OH caused the disassembly of cell wall material (CWM) in vitro, demonstrated by the increases of total sugars and uronic acid released, and the downshift in molecular mass of CDTA soluble pectin (CSP) and Na2CO3 soluble pectin (CO3-SP). In addition, OH resulted in decreased CO3-SP content and increased CSP content in CWM suspension, suggesting the conversion of CO3-SP to CSP. Application of exogenous OH accelerated aril breakdown in longan fruit while the process was delayed by l-cysteine·HCl, a ROS scavenger. Furthermore, lower CWM content and decreased molecular mass of pectins were observed in OH-treated fruit. These results indicated that OH contributed to the degradation of cell wall polysaccharides, resulting in aril breakdown in longan fruit.

Histone deacetylation plays an important role in epigenetic control of gene expression. HD2 is a plant-specific histone deacetylase that is able to mediate transcriptional repression in many biological processes. To investigate the epigenetic and transcriptional mechanisms of longan fruit senescence, one histone deacetylase 2-like gene, DlHD2, and two ethylene-responsive factor-like genes, DlERF1 and DlERF2, were cloned and characterized from longan fruit. Expression of these genes was examined during fruit senescence under different storage conditions. The accumulation of DlHD2 reached a peak at 2 d and 30 d in the fruit stored at 25 °C (room temperature) and 4 °C (low temperature), respectively, or 6 h after the fruit was transferred from 4 °C to 25 °C, when fruit senescence was initiated. However, the DlERF1 transcript accumulated mostly at the later stage of fruit senescence, reaching a peak at 5 d and 35 d in the fruit stored at 25 °C and 4 °C, respectively, or 36 h after the fruit was transferred from low temperature to room temperature. Moreover, application of nitric oxide (NO) delayed fruit senescence, enhanced the expression of DlHD2, but suppressed the expression of DlERF1 and DlERF2. These results indicated a possible interaction between DlHD2 and DlERFs in regulating longan fruit senescence, and the direct interaction between DlHD2 and DlERF1 was confirmed by yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays. Taken together, the results suggested that DlHD2 may act with DlERF1 to regulate gene expression involved in longan fruit senescence.

A highly specific and sensitive indirect competitive enzyme-linked immunosorbent assay (icELISA）was developed for the first time for the detection of chrysoidine, a dye banned in soybean milk film. Two haptens with different spacer arms were synthesized to produce antibodies. Both homologous and heterologous immunoassay formats were compared to enhance the icELISA sensitivity. The heterologous icELISA exhibited better performance, with an IC(50) (50% inhibitory concentration) of 0.33 ng/mL, a limit of detection (LOD, 10% inhibitory concentration) of 0.04 ng/mL, and a limit of quantitation (LOQ, 20%-80% inhibitory concentration) from 0.09 to 4.9 ng/mL. The developed icELISA was high sensitive and specific, and was applied to determine chrysoidine in fortified soybean milk film samples. The results were in good agreement with that obtained by high-performance liquid chromatography (HPLC) analyses.

Inhibitory effects of the Noble muscadine grape extracts and the representative phytochemicals for anthocyanins (i.e., cyanidin and cyanidin-3,5-diglucoside) on two enzymes, that is, α-glucosidase and pancreatic lipase, were investigated regarding their antidiabetic activities. The study demonstrated that the anthocyanin extracts and the selected chemicals obeyed the competitive mode against the enzymes. The methanolic extracts of whole fruit and skin of the muscadine showed inhibitory activities against the α-glucosidase with their IC(50) values at 1.50 and 2.73 mg/mL, and those against the lipase at 16.90 and 11.15 mg/mL, respectively, which indicated that the muscadine extracts possessed strong antidiabetic activities. Particularly, the ethyl acetate (EtoAc) extract and the butanol (BuOH) extract exhibited much higher inhibitory activities against both enzymes than the CHCl(3) and water extracts, while the majority of anthocyanins existed in the BuOH fractions. Moreover, cyanidin exhibited a much stronger antidiabetic activity than cyanidin-3,5-diglucoside, suggesting that anthocyanins may have higher inhibitory activities after being digested. Further chromatographic analysis by high-performance liquid chromatography-mass spectrometry identified five individual anthocyanins, including cyanidin, delphinidin, petunidin, peonidin, and malvidin glycosides.

Polyhexamethylene biguanide (PHMB) and polyhexamethylene guanide (PHMG) are broad-spectrum antibacterial agents. Experiments were conducted to investigate the antifungal activities of PHMB and PHMG against a major citrus sour rot pathogen Geotrichum citri-aurantii both in vitro and in vivo . PHMG and PHMB treatments significantly inhibited arthroconidia germination and mycelial growth of G. citri-aurantii in vitro . PHMG and PHMB at 5 mg/L inhibited 97.8% and 95.8% of the germination of G. citri-aurantii arthroconidia, respectively. Observations by light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) further showed ultrastructural alterations caused by PHMG or PHMB treatments, including distortion, deformation and concave collapse in hyphae, plasma membrane disruption in both hyphae and arthroconidia, and cell wall damage in arthroconidia. Use of PHMG and PHMB significantly ( P

The effects of pure oxygen on pericarp browning, reactive oxygen species (ROS) metabolism, antioxidant enzyme and antioxidant activity of harvested litchi fruit were investigated. Application of pure oxygen significantly prevented pericarp browning and delayed the increase in membrane permeability of litchi fruit during storage. Litchi fruit exposed to pure oxygen showed a lower level of lipid peroxides, compared to control fruit, with the delay in the increases of both H 2 O 2 content and superoxide production rate. Furthermore, it was found that the treatment with pure oxygen induced the activities of superoxide dismutase (SOD), ascorbated peroxidase (APX) and catalase (CAT), which could be beneficial in scavenging of H 2 O 2 and superoxide and alleviating lipid peroxidation. In addition, antioxidant ability (reducing power and free-radical scavenging activity against DPPH radical, superoxide anions and hydroxyl radical) of methanol extracts from litchi fruit pericarp declined gradually, with decreasing contents of anthocyanins and phenolic compounds, as storage time of the fruit progressed. There was a linear relationship between the contents of either anthocyanins or phenolic compounds and antioxidant ability or free radical scavenging activity. Treatment with pure oxygen markedly increased antioxidant ability, which was related to higher levels of anthocyanins and phenolic compounds, compared with those of control fruit. It is suggested that enhanced antioxidant activity and antioxidant enzyme induced by pure oxygen may contribute to alleviating lipid peroxidation and maintenance of membrane integrity, which reduced decompartmentation of enzymes and substrates, resulting in enzymatic browning.

Mature longan (Dimocarpus longan Lour.) fruit has a succulent, edible and white aril, which has gained popularity as an exotic fruit in temperate regions. It is prized on the international market resulting in an increased production with significant contributions to local economic development. Longan fruit contains significant amounts of bioactive compounds such as corilagin, ellagic acid and its conjugates, 4-O-methylgallic acid, flavone glycosides, glycosides of quercetin and kaempferol, ethyl gallate 1-β-O-galloyl- d -glucopyranose, grevifolin and 4-O-α- l -rhamnopyranosyl-ellagic acid. The fruit has been used in the traditional Chinese medicinal formulation, serving as an agent in relief of neural pain and swelling. The application of ultrasonic-assisted extraction or high pressure-assisted extraction greatly increases the yield from longan pericarp or seeds. In recent years, some pharmacological activities such as anti-tyrosinase, anti-glycated and anticancer activities, and memory-enhancing effects of longan aril, pericarp or seed extract have been found, implicating a significant contribution to human health. Regarding the increasing cultivation area and increasing quantity of longan fruit in the world, further utilization of this fruit is expected in an effort to use more efficiently the inherent bioactive compounds. The paper reviews the recent advances in the extraction and pharmacological activities of bioactive compounds from longan fruit. Some novel pharmacological potential of longan fruit is also discussed in this paper.

para-aminosalicylic acid (PAS; 4-amino-2-hydroxybenzoic acid), an antituberculosis drug in use since the 1950s, has recently been suggested to be an effective agent for treatment of manganese-induced parkinsonian disorders. However, the neuropharmacokinetics of PAS and its metabolite N-acetyl-para-aminosalicylic acid (AcPAS; N-acetyl-4-amino-2-hydroxybenzoic acid) are unknown. This study was designed to investigate the pharmacokinetics of PAS and its distribution in brain to help better design the dosing regimen for clinical trials. Male Sprague-Dawley rats received single femoral artery injections of PAS (200 mg/kg). Plasma, cerebrospinal fluid, and brain tissues were collected, and PAS and AcPAS concentrations were quantified by high-performance liquid chromatography. After administration, the concentrations of PAS declined rapidly in plasma with an elimination t(½) of 34 min; the metabolite AcPAS was detected in plasma and eliminated with a t(½) of 147 min. PAS and AcPAS were detected in brain tissues; AcPAS had a much higher tissue concentration and a longer t(½) than the parent PAS in most tissues examined. Although both were present in blood or tissues as free, unbound molecules, AcPAS appeared to have a higher tissue affinity than PAS. Taken together, our results suggest that a dosing regimen with continuous intravenous infusion of PAS is necessary to achieve therapeutic levels in targeted brain regions. Furthermore, PAS and AcPAS seem to be effective in reducing manganese levels in brain.

The effect of oxalic acid application on plum fruit ( Prunus salicina cv. ‘Damili’) ripening properties during storage or shelf-life was determined. The fruits were dipped for 3 min in solutions containing 5 mmol/L oxalic acid and then were packed into polyethylene bags and stored at 25 °C for 12 days, or at 2 °C for 20 days and subsequently at 25 °C for 12 days. Ethylene production, fruit firmness, contents of pectin and anthocyanin, specific activities of polygalacturonase (PG), pectin methylesterase (PME) and phenylalanine ammonia lyase (PAL), and chlorophyll fluorescence (Fv/Fm) were measured. The application of oxalic acid reduced ethylene production and delayed softening of plum fruit. The inhibition of softening was associated with decreased PG and PME activities; that is, the retardation of pectin solubilization/degradation. During storage or shelf-life, flesh reddening and anthocyanin synthesis were significantly inhibited in oxalic acid-treated plum fruit, accompanied with decreased PAL activity. Furthermore, it was found that variable:maximalchlorophyll fluorescence (Fv/Fm), an indicator of ripening, senescence or stress injury of fruit and vegetable, decreased much more slowly in oxalic-treated plum fruits than in control fruits. Thus, oxalic acid treatment can be an effective means to extend the shelf life of plum fruit.

An indirect competitive enzyme-linked immunosorbent assay (icELISA) with enhanced specificity for melamine in milk was developed. Three haptens of melamine with different spacer-arms were used to prepare different plate coating antigens. It was found that the icELISA show best sensitivity and specificity to melamine when using the coating antigen prepared by coupling 3-(4,6-diamino-1,6-dihydro-1,3,5-triazin-2-ylthio)propanoic acid (Hapten C) with ovalbumin (OVA). The 50% inhibitory concentration (IC50) value was 35.4 ng·mL−1, the limit of detection (LOD) was 8.9 ng·mL−1 and the detectable working range (20–80% inhibitory concentration) was from 14.9 to 108.5 ng·mL−1, respectively. Compared to the ELISA results previously reported, the developed icELISA in the present study showed a much lower cross-reactivity to cyromazine, a fly-killing insecticide widely used in vegetables and stables. Recoveries obtained from milk samples in this study were in agreement with those obtained using the HPLC-MS method, indicating the detection performance of the icELISA could meet the requirement of the residue limit set by the Codex Alimentarius Commission. Therefore, the developed immunoassay can be applied for the analysis of melamine presented in milk.

Oligosaccharides have attracted much attention due to the beneficial health effect on human beings. Oligosaccharides were extracted from soy sauce lees (SSLO) and were purified in this work. It was a mixture of oligosaccharides, which accounted for 80.5% of the total weight, and free monosaccharides. Only two monosaccharides, xylose and mannose, were detected in the molecular chain of SSLO. Their relative molar percentages were 53.2% and 46.8% for the oligosaccharide and monosaccharide fractions, respectively. A dose-dependent behaviour was observed for the growth promoting effect of SSLO on Lactobacillus bulgaricus and Streptococcus thermophilus . When 200 μg/ml of SSLO was applied, the L. bulgaricus concentration was 15.7-fold higher than the control, whilst the S. thermophilus concentration was 34.7-fold higher than the control. The analysis of DPPH radical scavenging activity indicated poor antioxidant activity of SSLO. It also suggested that the prebiotic effect was not correlated with antioxidant activity.

The contents of starch and catechins in the fresh leaf of ‘Huang Zhi Xiang’ Oolong tea trees girdled at the bottom, middle (on the big branches) and top (on the small branches) were determined. The study demonstrated that the starch contents from girdled trees were significantly higher (p < 0.05) than that from non-girdled ones. Furthermore, the contents of (−)−epicatechin (EC), (−)−epigallocatechin (EGC), total catechins (TC) and simple catechins (SC) from girdled trees were significantly higher (p < 0.05) than those from non-girdled ones. Especially, the contents of (−)−epigallocatechin gallate (EGCG), (−)−epicatechin gallate (ECG) and catechin gallate (CG) from girdled at the middle were also significantly higher (p < 0.05) than those from the non-girdled. The starch contents were negatively correlated with the contents of (−)−gallocatechin (GC), EC, SC, TC and EGC, while positively correlated with the contents of EGCG and CG in fresh shoots.

Fruits and vegetables are colorful pigment-containing food sources. Owing to their nutritional benefits and phytochemicals, they are considered as ‘functional food ingredients’. Carotenoids are some of the most vital colored phytochemicals, occurring as all-trans and cis-isomers, and accounting for the brilliant colors of a variety of fruits and vegetables. Carotenoids extensively studied in this regard include β-carotene, lycopene, lutein and zeaxanthin. Coloration of fruits and vegetables depends on their growth maturity, concentration of carotenoid isomers, and food processing methods. This article focuses more on several carotenoids and their isomers present in different fruits and vegetables along with their concentrations. Carotenoids and their geometric isomers also play an important role in protecting cells from oxidation and cellular damages.

Silver-based nanostructures are suitable for many biomedical applications, but to be useful therapeutic agents, the high toxicity of these nanomaterials must be eliminated. Here, we biosynthesize nontoxic and ultra-small silver nanoclusters (rsAg@NCs) using metabolites of usnioid lichen (a symbiotic association of algae and fungi) that exhibit excellent antimicrobial activity against fluconazole (FCZ)-resistant Candida albicans that is many times higher than chemically synthesized silver nanoparticles (AgNPs) and FCZ. The rsAg@NCs trigger apoptosis via reactive oxygen species accumulation that leads to the loss of mitochondrial membrane potential, DNA fragmentation, chromosomal condensation, and the activation of metacaspases. The proteomic analysis clearly demonstrates that rsAg@NCs exposure significantly alters protein expression. Most remarkable among the down-regulated proteins are those related to glycolysis, metabolism, free radical scavenging, anti-apoptosis, and mitochondrial function. In contrast, proteins involved in plasma membrane function, oxidative stress, cell death, and apoptosis were upregulated. Eventually, we also established that the apoptosis-inducing potential of rsAg@NCs is due to the activation of Ras signaling, which confirms their application in combating FCZ-resistant C. albicans infections.

The 5-methyltetrahydrofolate (5MTHF) is the predominate folate form that exists in navy beans and possesses health benefit to human beings. Understanding the degradation kinetics of 5MTHF during navy bean processing would provide useful information that characterizes the influence of processing conditions in order to minimize folate degradation and to maintain overall products quality during the beans’ production. The bio-specific procedures were used for sample preparation and purification, and HPLC techniques were subsequently used for identification and quantitative analysis of 5MTHF in the different treated bean samples. Losses of 5MTHF have been observed in all processed navy beans. Experimental results showed that the soaking time and the seed-to-water ratio were the two most critical factors that affected the stability of 5MTHF during the soaking process. The longer soaking times with larger amounts of soaking water caused higher degradation of 5MTHF. Cooking time and cooking media also played a key role in the degradation of 5MTHF in beans. Pressurized cooking showed the highest reduction of 5MTHF among all the treated bean samples. The treatment causes greater folate loss mainly through the promotion of water penetration and high diffusion, leading to more folate being released from the bean matrix, and accelerating the oxidation and decomposition of folates during cooking.

The proteins of soy sauce lees (SSLP) were hydrolysed by Alcalase in the presence of ultrasound or traditional water bath to obtain hydrolysates S2–S6. The analysis of protein content indicated that enzymatic hydrolysis could significantly improve the extraction efficiency of proteins. By determination of molecular weight distribution, >10 and 5–10 KDa fractions of native SSLP (S1) decreased during hydrolysis, whilst 3–5 KDa fraction increased. Gradual increases of free, total and antioxidant amino acids were observed for S1–S4, and the differences between S4 and S6 were slight. Tyrosine was the major free amino acid of S1–S6, whilst glutamic acid had the highest amount in total amino acid composition. S2–S6 showed stronger DPPH radical scavenging activities in a dose-dependent manner than S1. All the results suggested that ultrasound treatment showed an inhibition behaviour on the enzymatic hydrolysis of SSLP.

The application of methyl jasmonate (MJ) for the control of pericarp browning of harvested lychees in relation to the levels of anthocyanins and (–)-epicatechin was investigated. Lychees were dipped for 3 min in 0.6 µg/L MJ + 0.05% Sportak, 1 µg/L MJ + 0.05% Sportak, 5 µg/L MJ + 0.05% Sportak, 25 µg/L MJ + 0.05% Sportak or 0.05% Sportak (control). In this study, contents of anthocyanins (–)-epicatechin and lipofuscin-like substance, and browning index of harvested lychees during storage were determined. The activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase and peroxidase were also measured. The treatment with MJ significantly maintained the contents of anthocyanins and (–)-epicatechin, delayed the accumulation of lipofuscin-like substance and extended the shelf life of lychees. Furthermore, MJ treatment increased PAL activity, which can account for the maintenance of anthocyanin or (–)-epicatechin content. After these treatments, 1 µg/L MJ was effective in inhibiting pericarp browning and in maintaining the contents of anthocyanins and (–)-epicatechin of lychees. Thus, it is suggested that maintenance of anthocyanin or (–)-epicatechin contents could be an important factor for controlling pericarp browning of lychees during storage. PRACTICAL APPLICATIONS Lychees are highly perishable after harvest because of rapid skin browning as a result of anthocyanin degradation and (–)-epicatechin oxidation by polyphenol oxidase or peroxidase in the presence of peroxides, and the subsequent accumulation of lipofuscin-like substance, a final product of the autooxidation of lipid hydroperoxides, malondialdehydes and proteins of cells. This study exhibited that treatment with 1 µg/L methyl jasmonate (MJ) inhibited significantly the degradation of anthocyanins and the oxidation of (–)-epicatechin, and delayed significantly the accumulation of lipofuscin-like substance and pericarp browning of lychees. Therefore, application of MJ could be an important strategy to extend storage life and maintain the quality of harvested lychees based on the maintenance of anthocyanin or (–)-epicatechin content.

Two new sesquiterpene glucosides, litchiosides A (1) and B (2), were obtained along with pumilaside A (3) and funingensin A (4) from lychee (Litchi chinensis Sonn.) seed. Their structures were elucidated on the basis of spectroscopic and chemical evidence. The in vitro antitumour activity of compounds 1–4 against A549, LAC, Hela, and Hep-G2 cell lines was determined using the MTT colourimetric assay. Pumilaside A (3) exhibited significant activity against all the tested cell lines with IC50 values of 0.012–6.29 μM, and funingensin A (4) showed moderate activity against Hep-G2 cells (IC50 = 39.27 μM), while litchiosides A (1) and B (2) were found to be inactive.

The effect of high-pressure homogenization (HPH) at 0.1 (control), 40 or 80 MPa on the denatured peanut protein were investigated. Solubility, emulsifying property, foaming property, differential scanning calorimetry (DSC) characteristic, water-holding capacity (WHC) and scanning electron microscope (SEM) analysis of the peanut protein isolates (PPIs) from the peanut flour after various HPH treatments were analyzed. Increased solubility of the denatured peanut protein by HPH treatment depended on the pH value. In the range of pH 4−7, the HPH-treated peanut protein exhibited a higher solubility than the non-HPH-treated protein, but the HPH treatment did not affect significantly the solubility in the range of pH 8−10. HPH treatment improved the emulsifying activity index (EAI) and foaming capacity (FC) but reduced the emulsifying stability index and foaming stability. In addition, HPH treatment markedly improved the WHC but slightly affected the DSC parameter. Based on the observation of SEM, many irregular fine crackles in the peanut protein after HPH treatment appeared, which showed that the treatment resulted in the change in the surface microstructure of the protein. These results indicated that the HPH treatment led to the modification of the microstructure of peanut protein and, thus, improved its functional properties such as EAI, FC and WHC. PRACTICAL APPLICATIONS Functional properties of plant and animal proteins are important in food processing and production formulation. Peanut exhibits an excellent potential as a source of plant proteins. Improvement of functional or nutritional properties of proteins can help produce some novel food products in food industry. The use of high-pressure homogenization (HPH) is one of the most efficient means to improve the functional properties of plant proteins. The study exhibited that application of HPH treatment resulted in the changed the microstructure of peanut protein and, thus, improved its functional properties such as the emulsifying activity index, foam capacity and water-holding capacity, which might be utilized in food industry.

Freshly harvested loquat (Eriobotrya japonica Lindl. 'Dahongpao') fruit were exposed to 100% N 2 for 6h at 20°C and then stored at 5°C for 35 days to investigate the effect of short-term N 2 treatment on the quality of the fruit. Fruit decay rate, total soluble solids (TSS) and total titratable acidity (TA) contents, membrane permeability, malondialdehyde (MDA) content were measured. The short-term N 2 treatment significantly delayed the increase of fruit decay rate and delayed the decreases of total soluble solids (TSS) and total titratable acidity (TA) contents, thereby maintaining better eating quality and extending the storage life of the fruit. The short-term N 2 treatment also markedly delayed the increases in membrane permeability, malondialdehyde (MDA) content. These results suggest that a prestorage pure N 2 treatment for 6h can effectively reduce fruit decay, delay the peroxidation of membrane lipid and maintain the quality of loquat fruit. Therefore, a short-term N 2 treatment in combination with low temperature could be a useful technique to maintain the quality of postharvest loquat fruit.

Oolong tea is a semi-fermented Chinese traditional tea that dates back centuries and now its unique characteristics are attracting more and more consumers worldwide. The formation of Oolong tea's special quality is attributed to the proper processing of the fresh tea leaf. The quality of Oolong tea can be evaluated by aroma, flavor, color, and appearance with aroma and flavor being the two most important quality indices. The formation of the distinct aroma of Oolong tea depends largely on the decomposition of lipids and carotenoids. However, other compounds that can be hydrolyzed and/or oxidized also contribute to Oolong tea's special aroma. During the processing of Oolong tea, some major flavor compounds are formed by the oxidation of catechins, amino acids, and sugars. The flavor of Oolong tea is complex due to the interaction of many different flavor compounds. Oolong tea exhibits antioxidant, anticancer, antiobesity, prevention of atherosclerosis and heart disease, antidiabetes, and antiallergic effec...

Banana is a climacteric fruit with desirable palatability and high nutritional value. It ripens rapidly accompanied with metabolite changes during postharvest storage. In this work, morin was applied to treat banana to delay senescence. Nuclear magnetic resonance (NMR) spectroscopy was used to monitor the changes of metabolite composition and levels in banana. The results showed that morin significantly delayed the changes of color and firmness. 1D and 2D NMR spectra reflected that the levels and composition of metabolites were changed with the senescence initiation. The principal component analysis revealed that the first principal components responsible for banana senescence were carbohydrates, amino acids, lipids and phenolics. Morin treatment delayed the transformation of starch to glucose, fructose and sucrose, accelerated the accumulations of alanine and &gamma, Amino-butyrate (GABA), postponed the generations of valine and l-aspartic acid, suppressed the degradation of saponin a. It indicated that morin was effective in delaying banana senescence.

Longan (Dimocarpus longan Lour.) fruit is highly susceptible to water loss and pericarp browning in storage. Postharvest pericarp browning of the fruit greatly affects its shelf-life. 'Fuyan' longans showed 5.84, 10.37 and 23.98% of total fruit weight losses, and 13.59, 26.40 and 42.78% of pericarp water losses, when stored at 10°C and 50% RH for 1, 2 and 6 days, respectively. However, minimal weight loss in aril and seed was observed. And, the selective dehydration of pericarp tissues occurred while little movement of water between the aril and the pericarp was found. The weight loss of the fruits and water loss in pericarp tissues significantly correlated to the pericarp browning at the 1% level. On the other hand, fruits stored in plastic bags under low temperatures reduced the moisture losses and pericarp browning. 'Fuyan' fruits packed in bags made of 0.015 mm polyethylene film and held for 15 days at 20°C lost 2.87% on a fresh weight basis, while they lost 2.01% at 4°C for 30 days. At the same time, storage at low temperature also retarded pericarp browning and extended the longan's shelf-life.

The crystalline, thermal and textural properties of chestnut starches (CSs I–V) at 0%, 25%, 50%, 75% and 100% degrees of hardening (DHs) were investigated in this work. CS I had a structure of C-type crystallinity. With the increase of DH, more B-type crystalline regions and amylose–lipid complexes were formed. The gelatinisation temperature of CS and melting temperature of amylose–lipid complexes were not significantly changed as DH increased. However, a significant (P

Hardening is an important physiological disorder of chestnut fruit during storage. In this study, polysaccharides of chestnut (PCs) at 0%, 50% and 100% degrees of hardening (DH) were extracted and then sequentially fractionated using 40% and 80% ethanol in order to obtain PCs I and II. For fresh chestnut, arabinose, fructose, glucose and galactose were the main monosaccharides of PCs I and II. Significantly positive correlations (P < 0.01) existed between xylose, galactose, arabinose contents and DH, while significantly negative correlations (P < 0.01) were present between glucose, fructose contents and DH for both PCs I and II. The appearance in hardening of chestnut fruit was accompanied with decreases in the contents of 1,3-fructose, 1,3- and 1,6-glucose, and increases of 1,4-arabinose, 1,6-galactose and 1,3-xylose. The results confirmed that cell wall degradation of chestnut induced the structural changes in PCs I and II, which further led to the occurrence of hardening.

The experiments were performed to extract and purify substrates for polyphenol oxidase (PPO) from pericarp tissue of postharvest litchi fruit. Two purified PPO substrates were identified as (−)-epicatechin and procyanidin A2. The antioxidant properties of two PPO substrates were further evaluated in the present study. Variation in the content of the major substrate (−)-epicatechin of litchi fruit during storage at 25 °C was analysed using the HPLC-UV method. The results showed that (−)-epicatechin exhibited stronger antioxidant capability than procyanidin A2, in terms of reducing power and scavenging activities of DPPH radical, hydroxyl radical and superoxide radical. Furthermore, (−)-epicatechin content in pericarp tissue tended to decrease with increasing skin browning index of litchi fruit during storage at 25 °C. Thus, these two compounds can be used as potential antioxidants in litchi waste and the fresh pericarp tissue of litchi fruit exhibited a better utilisation value.

The variations in the contents of catechins and phenolic compounds in relation to the quality scores (QS) and taste scores (TS) in the ‘ Huang Zhi Xiang ’ Oolong tea grown in different seasons and at different altitudes were determined. The study demonstrated that the contents of (−)-epigallocatechin gallate (EGCG), catechin gallate (CG), and total catechins (TC) in the Oolong teas grown at a high altitude were significantly higher than those grown at a low altitude. Furthermore, the contents of EGCG, CG, and TC in the autumn tea were significantly higher than those from the spring tea grown at a low altitude. However, no significant differences in the contents of EGCG, CG, and TC were observed between the spring and autumn teas grown at a high altitude. In addition, the contents of (−)-epigallocatechin (EGC), (+)-catechin (C), (−)-gallocatechin (GC), and simple catechins (SC) in the spring tea leaves were significantly higher than those in the autumn tea leaves grown at a low altitude, but they were not significantly different from those in the autumn tea leaves grown at a high altitude. The contents of EGCG, CG, and TC in the Oolong teas were positively and significantly correlated to the taste score (TS) and quality score (QS) of the Oolong tea. Thus, the contents of EGCG, CG, and TC could be the important quality parameters of the ‘ Huang Zhi Xiang ’ Oolong tea. This work suggested that the production of the ‘ Huang Zhi Xiang ’ Oolong tea grown at low altitudes should utilize the autumn tea leaves while the production of Oolong tea grown at high altitudes can use both the spring and autumn tea leaves.

Experiments were conducted to examine softening and quality responses of harvested banana fruit to cold shock treatment intended to extend shelf-life. Fruit were immersed in ice-water for 1 h, then treated with or without 100 μL L−1 ethylene for 24 h at 24 °C, and finally stored at 20 °C. Fruit firmness, chlorophyll content, ethylene production, respiration rates, contents of pectin, starch and sugar, and the activities of the cell wall modifying enzymes polygalacturonase (PG), pectin methylesterase (PME) and CMCase (cellulase, endo-1,4-β-glucanase) were analyzed. Total amylase activity was also measured. Immersion in ice-water for 1 h effectively inhibited ripening-associated processes, including peel de-greening and pulp softening during storage or ripening. The delay in ripening was also manifest in reduced ethylene production and respiration rates. The inhibition of softening by cold shock treatment was related to decreased PG and PME activities, that is, retardation of pectin solubilization/degradation. Reduced activities of CMCase and total amylase and conversion of starch to sugar by ice-water immersion also contributed to the delay in softening of harvested banana fruit.

Polysaccharides play important roles in physiological and pathological effects. Experiments were conducted to compare various methods of polysaccharides extracted from a mulberry leaf using the orthotropic test, and then to determine the optimum extraction conditions. The antioxidant activity and antibacterial ability of mulberry polysaccharides were also evaluated. In this study, the optimum extraction conditions of mulberry polysaccharides were determined to be a ratio of mulberry leaf to water solution of 1:40 (w/v) for 1 h at 80C. Under these optimum conditions, a polysaccharide yield (11.3%) was obtained. Furthermore, the most effective enzymatic removal of proteins from mulberry polysaccharides was achieved using 2.5% protease for a 2.5-h reaction at 40C, with 73.2% of the protein removal proportion and 86.4% of the polysaccharide proportion, while application of active carbon was the best treatment to remove pigments present in mulberry polysaccharides, with 81.4% of the pigment removal proportion and 71.7% of the polysaccharide proportion. In addition, the antioxidant activity and bactericidal ability of mulberry polysaccharides were evaluated. This study indicated that mulberry polysaccharides exhibited an obvious antioxidant activity in a dose-dependent manner and distinct antibacterial ability. PRACTICAL APPLICATIONS There is increasing interest of utilizing polysaccharides from plant sources for their bioactive activities. As extraction conditions greatly influence polysaccharide yield and quality, great attention has been paid to the efficient extraction of polysaccharides from mulberry leaf. In this study, the optimum extraction conditions of polysaccharides from mulberry leaf were obtained using a ratio of mulberry leaf to water solution of 1:40 (w/v) for 1 h at 80C. Application of protease was the most effective in removing proteins, while active carbon was the best treatment to remove pigments present in mulberry polysaccharides. Moreover, mulberry polysaccharides exhibited a strong antioxidant activity and a good antibacterial ability. This study can help better utilize mulberry polysaccharides, especially as a readily accessible source of natural antioxidants and/or possible antibacterial agents in food or pharmaceutical industry.

Pumpkin is a traditional food that is grown extensively worldwide and is believed to be beneficial to human health due to its high contents of carotenoids. The carotenoids in pumpkin were extracted by organic solvents and by supercritical carbon dioxide (SC-CO 2 ), and then they were identified, quantified, and compared. β-carotene (31 to 40 g per 100 g of total carotenoids) was the predominate carotenoid in pumpkin. Lutein and lycopene contents were much higher in SC-CO 2 extracts than those in organic solvent extract. Cis -β-carotene increased by more than two times in the SC-CO 2 extracts, even at a relatively low temperature of 40 °C, over those in the solvent extracts, indicating both enhanced solubility and isomerization from trans - to cis -β-carotene. The influences of modifier (10 mL/100 mL), temperature (40–70 °C), and pressure (25–35 MPa) of SC-CO 2 extraction on the change of carotenoid yields were also investigated. The highest yield (109.6 μg/g) was obtained at 70 °C and 35 MPa, with a 73.7% recovery. Selective extraction could be achieved by adjusting the temperature and pressure. Higher proportions of all- tran s-β-carotene extracts were achieved at 40 °C under both 25 MPa and 35 MPa conditions. In order to extract more cis -isomers, a higher temperature of 70 °C was preferred.