•SPHs protect cells against Pb2+-induced morphological changes of apoptosis.•Caspase-dependent mitochondria pathway was potential protection mechanism of SPHs.•Bcl-2 protein family and cytochrome C were involved in protection mechanism of SPHs.•SPHs were low molecular weight Se peptides.This study aimed to investigate the protection mechanism of Se-containing protein hydrolysates (SPH) from Se-enriched rice on Pb2+-induced apoptosis in PC12 and RAW264.7 cells. Results showed that SPHs could alleviate Pb2+-induced morphological changes of apoptosis and the loss of mitochondrial transmembrane potential in both cell types. Besides this, SPHs could significantly reduce the activation of caspase-3, -8, -9 induced by Pb2+, reverse the Pb2+-induced upregulation of Bax and release of cytochrome C, and downregulate Bcl-2 in cells. HPLC-ICP-MS and SEC-HPLC assays showed that SPHs were low molecular weight peptides (229.4–534.9 Da), and the major Se species found in SPHs was SeMet. Taken together, these findings suggested that SPHs could possibly protect the cells against Pb2+-induced apoptosis via a caspase-dependent mitochondrial pathway, and the primary effective constituents in SPHs were SeMet and Se-containing peptides, suggesting that SPHs might be a novel potential candidate to improve the health of people with Se deficiency or in Pb-contaminated areas.

•A new nanocomposite packaging material was prepared.•It was applied on the preservation of mushrooms (F. velutipes).•Non-volatile and volatile compounds from F. velutipes were evaluated.•The different flavours were tested using E-nose, E-tongue and HS-SPME–GC–MS.•The ethanol accumulation and amino acids degradation were inhibited during storage.To clarify the dynamic changes of flavour components in mushrooms packed with different packaging materials during storage, comprehensive flavour characterization, non-volatile and volatile compounds of Flammulina velutipes were evaluated using electronic nose (E-nose), electronic tongue (E-tongue) technology and headspace solid phase micro-extraction combined with gas chromatography–mass spectrometry (HS-SPME–GC–MS), respectively. Results showed that volatile compounds of fresh F. velutipes mainly consisted of ketones and alcohols, with 3-octanone being the predominant compound. After storage, volatile components significantly changed in mushrooms packed with normal packaging material (Normal-PM) according to the GC–MS analysis and radar fingerprint chart of electronic nose. The ethanol accumulation was inhibited by nanocomposite packaging materials (Nano-PM). Besides, both radar graph and PCA of E-tongue signals could differentiate the samples from different packaging and storage time. In general, these results may provide a profile of flavour substances and explain mechanism of flavour changes in F. velutipes over storage period.

•Mushroom protein isolate hydrolyzed with single and sequential enzymes.•High MPH yields (>84%) and PR of >80% in the low MW fractions (<3 kDa).•Higher DRSA and FRAP in 1–3 kDa for single than for sequential enzyme hydrolysis.•Better Fe2+ chelating activity in the MPHs than in the UFs.•Potential application of MPHs and UFs as bioactive ingredients.Mushroom protein isolate (MPI) from Agaricus bisporus was hydrolyzed using Alcalase, Pancreatin, Flavourzyme, Alcalase-Pancreatin and Alcalase-Flavourzyme. The obtained hydrolysates (MPHs) were ultrafiltered to generate peptide fractions (UFs) of molecular sizes (<1, 1–3, 3–5 and 5–10 kDa). The electrophoretic profile results indicated that the enzymatic systems were efficient in hydrolyzing the MPI into low molecular weight peptides. Hydrolysate yields of >57% and protein recoveries of >43% were obtained. Effective concentration that scavenged 50% (EC50) of DPPH radicals was similar for the MPHs while inhibition against linoleic acid oxidation was strongest (66.49%) for Alcalase-Flavourzyme hydrolysate on day 5 of incubation. UFs exhibited a concentration-dependent FRAP, with the highest activity for fractions from Alcalase and Pancreatin recorded in 1–3 kDa. The antioxidant activities of MPHs and their UFs suggested that they could be potential bioactive ingredients for use in the formulation of functional foods as well as natural antioxidants in lipid food systems.

Edible mushrooms are rich sources of bioactive components. In this study, a bioactive protein, PEP, was isolated from an edible mushroom, Pleurotus eryngii, through (NH4)2SO4 precipitation and ion-exchange chromatography. Proteomic analysis by matrix assisted laser desorption ionization-time of flight mass spectrometry showed that PEP was a novel protein with a molecular weight of 40 kDa. PEP exhibited anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages by inhibiting the overproduction of pro-inflammatory mediators including nitric oxide (NO), cytokine IL-1β and IL-6. It was further demonstrated that these anti-inflammatory effects of PEP were associated with the inhibition of inducible nitric oxide synthase (iNOS) expression, and the deactivation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Our results demonstrated that PEP might be a good candidate for anti-inflammation in the gastrointestinal tract, especially in the colon.

A novel, homogeneous Pleurotus eryngii polysaccharide (PEP) (molecular weight 426 kDa, purity 91.25 ± 3.14%) which mainly consisted of glucose with β-type glycosidic linkages was used to investigate in vivo fermentation behavior and effects on immune response in mice. Different doses (0.2, 0.4, 0.8 g per kg body weight) were orally administered to the mice for a period of six weeks. The results showed that the SCFA concentration, pH value, and moisture contents of cecum and colon contents were significantly altered with high-dose PEP treatment compared to the control group (P < 0.05). Moreover, the fecal microbiota in the PEP treated group was found to be structurally different compared to the control group; especially, the Porphyromonadaceae, Rikenellaceae, Bacteroidaceae and Lactobacillaceae abundances were all increased at the family level. In addition, the exerted immune response was significantly altered after the high-dose PEP oral administration. This exploratory study indicated that intake of PEP could have a positive role in gastrointestinal tract health.

Edible mushrooms have been considered as a good source of bioactive components with various health benefits. Our previous study demonstrated the identity of a novel protein from Pleurotus eryngii, namely PEP, and its anti-inflammatory activities. Herein, we further determined the inhibitory effects of PEP against colon cancer cells. PEP suppressed the proliferation of human and murine colon cancer HCT116 and MC38 cells in a dose and time-dependent fashion, while it showed no inhibitory effect on normal human colonic myofibroblasts CCD-18Co at the same concentrations tested. Moreover, PEP induced cell cycle arrest and led to extensive cellular apoptosis in colon cancer cells, which was associated with the downregulation of cell cycle-related signaling proteins, e.g. cyclin B, cyclin E and cdc-2, and the upregulation of apoptosis-related signaling proteins, e.g. p53 and c-PARP. The results from an in vivo study showed that PEP treatment significantly suppressed tumor development of allograft colon cancer cells in mice, and this inhibition was associated with the upregulation of p21, p53, caspase-3 and cleaved caspase-3. Overall, our results provided a basis for PEP as a promising preventive agent against colon cancer.

Fatigue is a biological phenomenon that involves a feeling of extreme physical or mental tiredness that could potentially cause some severe chronic diseases. Recently, diet therapy has provided a new alternative to alleviate physical fatigue. In our previous study, addition of Cordyceps militaris (C. militaris) into an extruded product was shown to provide high nutrition and unique flavors; however, little is known whether this product has some scientific evidence regarding anti-fatigue property. The purpose of this study was to evaluate the anti-fatigue effects of extruded products of cereal grains (EC) and EC mixed with C. militaris (ECC).The mice were divided into seven groups: one group received distilled water (Control group, n = 20), and the other groups received different dosages of EC (5, 10 and 20 g/kg body weight, n = 20 per group) or of ECC (5, 10 and 20 g/kg body weight, n = 20 per group) solution in water. All of the mice were administered with distilled water, EC or ECC continuously for 30 days by gavage and the anti-fatigue activity was evaluated using a weight-loaded swimming test, along with assessments of fatigue-related indicators. The mode of fighting fatigue was investigated by determining changes in exercise endurance and biochemical markers, including exhaustive swimming time, lactate dehydrogenase (LDH), blood lactic acid (BLA), creatine kinase (CK), blood urea nitrogen (BUN), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and hepatic and muscle glycogen levels.EC and ECC prolonged the swimming endurance time of mice compared to the control. The content of BLA at high dose of ECC group (20 g/kg) was significantly lower than that in the negative control group. CK, BUN and MDA levels were significantly reduced by treatment with EC and ECC compared to the negative control, while the low and middle dose of EC had no significant effect on MDA levels. Additionally, only the middle and high dose of EC (10, 20 g/kg) could significantly decrease the BUN level. EC and ECC treatments increased glycogen, LDH, SOD, CAT and GSH-Px levels. Low and middle dose of EC had no significant effects on muscle glycogen. Moreover, low dose of EC could increase the level of SOD but it was not statistically significant. Compared to the EC treatment groups, ECC demonstrated the efficacy of anti-fatigue potential, particularly at a high dose of ECC, the best performance in relieving fatigue.These results suggest that EC and ECC could prevent exercise-induced fatigue in mice and ECC provided a better effect. In addition, C. militaris in ECC might play a crucial role in the anti-fatigue activity of ECC.

•Polysaccharides from F. velutipes (FVP) improved spatial search behaviour of rats.•FVP restored the level of ACh by modulating the ChAT and AChE activities.•FVP elevated SOD and GSH-Px activities and Connexin 36 and p-CaMK II expression.•FVP was potent agent against the progression of learning and memory impairment.Flammulina velutipes has been reported to be beneficial in learning and memory capabilities, but the mechanisms underlying this remain unclear. In this study, Morris water maze and biochemical analyses of rat brain were used to evaluate the effects of F. velutipes polysaccharides (FVP) on scopolamine-induced learning and memory impairments. Results suggested that FVP significantly decreased the escape latency and total swimming distance of rats in the hidden platform test and increased the numbers of platform crossing and swimming distance of rats in the probe test. Biochemical examinations revealed that FVP significantly elevates SOD and GSH-Px activities, as well as neurotransmitter levels. The increased acetylcholine content owed to the increased acetylcholine acetyltransferase activity and decreased acetylcholinesterase activity. Moreover, learning and memory associated signalling pathways were activated by FVP elevating the expression of connexin 36 and p-CaMK II. These results conclusively proved that FVP is a potent agent against the progression of cognitive impairment.

•Rice samples from different growing regions in China had a significant difference in Pb, Cd and As content.•In fresh edible mushroom, Pb and Hg contents in 2.6% samples were above MAC.•More than 95% rice and edible mushroom samples in our test had high edible safety.In this study, four common heavy metals, lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) in rice and edible mushrooms of China were studied to evaluate contamination level and edible safety. Ninety two (92) rice samples were collected from the main rice growing regions in China, and 38 fresh and 21 dry edible mushroom samples were collected from typical markets in Nanjing City. The analyzed metal concentrations were significantly different between rice and edible mushroom samples (p < 0.05). The results showed that Pb, Cd and As contents in 4.3%, 3.3% and 2.2% rice samples respectively, were above maximum allowable concentration (MAC). In fresh edible mushroom, Pb and Hg contents in 2.6% samples were above MAC, respectively. However, only Hg content in 4.8% dry edible mushroom samples was above its MAC. Therefore, more than 95% rice and edible mushroom samples in our test had high edible safety.

•Freeze drying (FD) and FD combined with microwave vacuum drying (FMVD) were investigated.•The taste profiles of button mushroom during the two drying processes were examined.•FMVD products had higher content of taste-active amino acids than FD products.•Equivalent umami concentrations (EUC) of FD/FMVD products were similar to fresh ones.•Compared to FD process, FMVD was more appropriate for button mushroom dehydration.Button mushroom slices were dehydrated using freeze drying (FD) or FD combined with microwave vacuum drying (FMVD), and the non-volatile component profiles were studied. The results showed that the level of non-volatile components in button mushroom firstly increased during sublimation of FD/FMVD process and then fell during desorption in FD process and MVD in FMVD process. Compared to FD products, the contents of soluble sugars and polyols in FMVD products were relatively low, whereas the contents of total free amino acids were significantly higher, close to the level of fresh mushroom. However, there was no significant difference in the contents of 5′-nucleotides and organic acids between FD and FMVD products. The equivalent umami concentration (EUC) values for FD and FMVD products did not differ from fresh, indicating that both drying methods could effectively preserve MSG (monosodium glutamate)-like components in button mushroom.

•Tea polyphenol-loaded chitosan nanoparticles (TP-CNPs) were prepared.•The antitumor effects of TP-CNPs were evaluated in HepG2 cells.•TP-CNPs could inhibit the proliferation of HepG2.•Cell apoptosis and cell cycle analysis reveal the antitumor mechanism.Tea polyphenols have strong antioxidant and antitumor activities. However, these health benefits are limited due to their poor in vivo stability and low bioavailability. Chitosan nanoparticles as delivery systems may provide an alternative approach for enhancing bioavailability of poorly absorbed drugs. In this study, tea polyphenol-loaded chitosan nanoparticles have been prepared using two different chitosan biomaterials, and their antitumor effects were evaluated in HepG2 cells, including cell cytotoxicity comparison, cell morphology analysis, cell apoptosis and cell cycle detection. The results indicated that the tea polyphenol-loaded chitosan nanoparticles showed a branch shape and heterogeneous distribution in prepared suspension. MTT assay suggested that tea polyphenol-loaded chitosan nanoparticles could inhibit the proliferation of HepG2 cells, and the cytotoxicity rates were increased gradually and appeared an obvious dose-dependent relationship. Transmission electron microscope images showed that the HepG2 cells treated with tea polyphenol-loaded chitosan nanoparticles exhibited some typical apoptotic features, such as microvilli disappearance, margination of nuclear chromatin, intracytoplasmic vacuoles and the mitochondrial swelling. In addition, the tea polyphenol-loaded chitosan nanoparticles had relatively weak inhibitory effects on HepG2 cancer cells compared with tea polyphenols. Tea polyphenols not only induced cancer cell apoptosis, but also promoted their necrosis. However, tea polyphenol-loaded chitosan nanoparticles exhibited their antitumor effects mainly through inducing cell apoptosis. Our results revealed that the inhibition effects of tea polyphenol-loaded chitosan nanoparticles on tumor cells probably depended on their controlled drug release and effective cell delivery. The chitosan nanoparticles themselves as the delivery carrier showed limited antitumor effects compared with their encapsulated drugs.

Button mushroom slices were dried using freeze-drying (FD) and freeze-drying combined with microwave vacuum drying (FD + MVD) methods. Drying parameters including drying temperatures (20, 30, and 40 °C), chamber pressures (70, 100, and 130 Pa) and material layer thicknesses (single, double, and triple) during FD process, and microwave power densities (20, 40, and 60 W/g) and material layer thicknesses (single, double and triple) during MVD period of FD + MVD process, were investigated for their drying characteristics. The FD and FD + MVD products were then rehydrated at two temperatures (20 and 70 °C). Different mathematical models were tested with the drying and rehydration behaviors of button mushroom slices, and the effective diffusivities (Deff) in the FD and FD + MVD processes were also calculated. The results indicated that based on the statistical tests, the Page model and logarithmic model provided the best fit for FD (in both FD and FD + MVD processes) and MVD (in FD + MVD process) curves, respectively. The regression equations obtained from selected models can accurately predict the relationships between moisture ratio (MR) and time (t). Furthermore, the Deff values of the MVD period in FD + MVD process (2.318–5.565 × 10−5 m2/s) were about ten times greater than those in FD process (1.291–3.389 × 10−6 m2/s). In addition, the Peleg model gave a better fit for rehydration conditions applied in both FD and FD + MVD products. The values of equilibrium moisture content (We) of FD + MVD products were almost similar to those of FD products, which indicated that the rehydration capacities of the two dehydrated products were comparable.

Freeze-drying (FD) and three different combinations of drying methods: freeze-drying combined with hot air drying (FD + AD), freeze-drying combined with vacuum drying (FD + VD) and freeze-drying combined with microwave vacuum drying (FD + MVD) were used to dry button mushroom slices. A comprehensive analysis of dried products was performed on their colour, texture, nutrient retention, microstructure and energy consumption. The results showed that, under conditions of 38 % moisture content changing point, most of the parameters including L* values, a* values, average density and hardness of FD + VD and FD + MVD samples had no remarkable changes (p > 0.05) compared with FD samples. However, only FD + MVD method can reduce drying time by 35.63 % in comparison of FD method, although all the combination drying methods can reduce the energy consumption. Moreover, FD + VD and FD + MVD products were better than FD + AD products in nutrient retention except that content of vitamin C was comparatively lower during FD + MVD process. In conclusion, the FD + MVD method has advantages in terms of efficiency and energy saving and could be preferred to produce high-quality products.

A polysaccharide was isolated from Flammulina velutipes (FVP) using ultrasonic-assisted extraction, and then further purified by DEAE cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography to afford FVP-1 and FVP-2. Structural characteristics of FVP-1 and FVP-2 (including molecular weight, monosaccharides composition, sulfate and uronic acid contents, triple helical structures, ultraviolet spectrum, and infrared spectrum) were investigated, and their anti-proliferation activities against human gastric cancer BGC-823 cells and lung cancer A549 cells were researched in vitro. Results suggested that both FVP-1 and FVP-2 could significantly suppress the proliferation of BGC-823 cells in a concentration-dependent manner. The highest inhibitory rates were 78% for FVP-1 and 95% for FVP-2 at the concentration of 200 μg/ml, respectively. This high anti-proliferation activity was inferred to be owing to the structural characterizations of polysaccharide, and the recognition of biological system for the triple helical structures of polysaccharides.Highlights► Isolation and characterization of two polysaccharides from Flammulina velutipes. ► Anti-proliferation activities of FVP-1 and FVP-2 against human BGC-823 and A549 cells. ► FVP-1 and FVP-2 exhibited strong antiproliferative potency in BGC-823 cell. ► Anti-proliferation activity was correlated with chemical structures of both polysaccharides.

Hexahydrocurcumin, 1-dehydro-[6]-gingerdione, 6-dehydroshogaol and 6-shogaol were evaluated for their antioxidant and anti-inflammatory activities in the present study. The relative antioxidant potencies of ginger compounds decreased in similar order of 1-dehydro-[6]-gingerdione, hexahydrocurcumin > 6-shogaol > 6-dehydroshogaol in both 1,1-diphenyl-2-picyrlhydrazyl (DPPH) radical-scavenging and trolox equivalent antioxidant capacity (TEAC) assays. All tested compounds could attenuate lipopolysaccharide (LPS)-elicited increase of prostaglandin E2 (PGE2) in murine macrophages (RAW 264.7) in a concentration-dependent manner but hexahydrocurcumin of 7 μM and 6-shogaol of 7 μM. The strongest inhibitory effect was observed for 6-dehydroshogaol and 6-shogaol at 14 μM with the inhibition of 53.3% and 48.9%, respectively. Furthermore, both 6-dehydroshogaol and 1-dehydro-[6]-gingerdione significantly suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in a concentration-dependent fashion. These results contribute to our theoretical understanding of the potential beneficial effects of consuming ginger as a food and/or dietary supplement.Highlights► Determination of in vitro antioxidant activity of four ginger compounds. ► Their effects on PGE2 release and expression of iNOS and COX-2. ► Hexahydrocurcumin and 1-dehydro-6-gingerdione showed the highest antioxidant capacity. ► 6-Dehydroshogaol and 6-shogaol exhibited the strongest PGE2 inhibition. ► iNOS and COX-2 were suppressed by 6-dehydroshogaol and 1-dehydro-6-gingerdione.

Chitosan nanoparticles (CS-NPs) were prepared by ionic gelation method using carboxymethyl chitosan and chitosan hydrochloride as carriers of tea polyphenols. The characteristics of chitosan-coated tea polyphenols nanoparticles (CS-TP NPs) were determined by using transmission electron microscopy (TEM) and FT-IR spectroscopy. It was found that the synthesized CS-TP NPs were non-spherical in shape with an average size of 407 ± 50 nm. Meanwhile, the drug content and encapsulation rate of the nanoparticles was 8–16% and 44–83%, respectively. These CS-TP NPs also demonstrated sustained release of tea polyphenols in PBS. The antitumor of CS-TP NPs towards HepG2 cancer cells was investigated. The result showed that CS-TP NPs retained significant antitumor activities.

Ultrasonic-aid extraction (UAE) was applied to the extraction of polysaccharides from Ganoderma lucidum and then the crude polysaccharides were purified by filtration, DEAE cellulose-52 chromatography and Sephadex G-100 size-exclusion chromatography in that order. Two main fractions, GP-1 and GP-2, were obtained through the extraction and purification steps. The characterizations, such as molecular weight, monosaccharides composition, ultraviolet spectrum and infrared spectrum of the two fractions were analyzed in this study. Furthermore, the influence of G. lucidum polysaccharides fractions upon activation of macrophage cell (RAW 264.7) and antitumor activities to the human breast cancer cell (MDA-MB-231) in vitro were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. The results indicated that GP-1 and GP-2 can increase the proliferation and pinocytic activity of macrophage significantly and play an inhibited effect on the cancer cell, moreover, the antitumor activity of the GP-1 and GP-2 increased with the participation of the antitumor factors induced from macrophage by polysaccharides fractions.

Selenium (Se) distribution in Se-enriched rice and optimization of extraction for Se-containing protein were studied. Se availability in Se-containing protein product was simulated using an in vitro gastrointestinal digestion. The results showed that Se was predominately found as organic Se, whereas inorganic Se comprised only 2.85% of the total Se. The glutelin fraction contained the largest amount of Se, approximately 31.3% of the total Se in the rice gain. Utilizing orthogonal analysis, the optimum extraction conditions were selected at a volume to weight of 20:1, 0.08 M NaOH, an extraction time of 3 h, and at a temperature of 35 °C. A Se-containing rice protein product with 83.5% protein and 9.09 μg g−1 Se was sequestered using the optimal extraction method. This rice protein product with high molecular weight Se-containing protein can readily be digested to low molecular weight peptides and selenomethionine (52.3% of total Se in protein extract).

Response surface methodology was used to optimize tea polyphenols-loaded chitosan nanoclusters preparation conditions, including carboxymethyl chitosan concentration, chitosan hydrochloride concentration and amount of tea polyphenols. The responses particle size and entrapment efficiency of nanoclusters were studied. The optimum conditions of carboxymethyl chitosan concentration, chitosan hydrochloride concentration and amount of tea polyphenols were found to be 3.63, 1.19 and 10.94 mg/mL, respectively. The optimized particle size was 301 nm, and entrapment efficacy of nanoclusters was added up to 83.7%. The results demonstrated that Box–Behnken design methodology was an effective way to obtain the optimal formulation of tea polyphenols-loaded chitosan nanoclusters, and the nanoclusters complexation synthesizing through ionic gelation between carboxymethyl chitosan and chitosan hydrochloride was good biomaterials, which could be successfully used to encapsulate tea polyphenols.

The effect of a novel nano-packing material on preservation quality of Chinese jujube (Ziziphus jujuba Mill. var. inermis (Bunge) Rehd) during room temperature storage was investigated. The nano-packing material with lower relative humidity, oxygen transmission rate and high longitudinal strength (2.05 g/m2 24 h, 12.56 cm3/m2 24 h 0.1 MPa and 40.16 MPa, respectively) was synthesized by blending polyethylene with nano-powder (nano-Ag, kaolin, anatase TiO2, rutile TiO2). The results showed that the nano-packing material had a quite beneficial effect on physicochemical and sensory quality compared with normal packing material. After 12-day storage, fruit softening, weight loss, browning and climatic evolution of nano-packing were significantly inhibited. Meanwhile, the contents of titrable acid and ascorbic acid were decreased to 0.21%, 251 mg/100 g, for nano-packing and 0.15%, 198 mg/100 g, for normal packing; The contents of total soluble sugar, reducing sugar, total soluble solids and malondialdehyde were increased to 28.4%, 5.2%, 19.5% and 98.9 μmol/g for nano-packing and 30.0%, 6.3%, 23.1% and 149 μmol/g for normal packing. Therefore, the nano-packing could be applied for preservation of Chinese jujube to expand its shelf life and improve preservation quality.

Se-enriched rice was prepared by foliar fertilization. In the present work, speciation and distribution of Se in Se-enriched rice and non-supplemented rice was evaluated by ion-paring reversed phase (IP-RP) and strong anion-exchange (SAX) chromatography coupled with inductively coupled plasma mass spectrometry (ICPMS) detection. Three extraction procedures: water extraction, acid extraction (0.1 M HCl) and enzymatic hydrolysis were studied with a combination of protease XIV and amylase with ultrasonic bath and the latter was found to be optimal for the extraction of selenospecies. The chromatograms obtained revealed that the major selenospecies found in Se-enriched rice was selenomethionine (SeMet), which was further identified by nanoelectrospray ionization, ion trap mass spectrometry (nano-ESI-ITMS). Approximately 86.9% of the total Se in the Se-enriched rice extract was SeMet, while only 26.7% of non-supplemented rice extract was due to SeMet. Moreover, nearly 60% of inorganic Se in the form of SeIV was present in the non-supplemented rice, while only 6.8% of inorganic Se as SeIV and SeVI was found in Se-enriched rice extract with minor selenocystine (SeCys2) and trace selenomethionine selenoxide (SeOMet) present. The results proved that SeMet was efficiently extracted by the enzymatic hydrolysis without oxidization. The high SeMet concentrations of Se-enriched rice indicate a high inorganic to organic conversion when Se enrichment was carried out by foliar application. Since SeMet is a readily bioavailable Se species for animals, Se-enriched rice could be considered for supplementation in Se poor geographical regions.

Response surface methodology was used to predict optimum conditions for hot air roasting of barley grains (temperature, time, and amount). Antioxidant capacity in the grains was highest under optimum conditions of 250 °C, 63.5 min and 42 g (one and a half layers). A correlation of R2 = 0.74 (p < 0.05) was found between 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic contents. Ethanol and aqueous extracts were prepared from grains roasted under optimum conditions and assessed for antioxidant capacity. Antioxidative compounds in the extracts were then identified using GC–MS. The IC50 value of ethanol extract was significantly lower (11.45 μg mL–1) than that of aqueous extract (33.54 μg mL–1) and α-tocopherol (12.6 μg mL–1) but higher than BHT (9.59 μg mL–1). The same trend was observed in linoleic acid assay. In reducing power, the ethanol extract and α-tocopherol were not significantly different. Phenolic acids p-hydroxybenzaldehyde, vallinic and gallic acids were identified as the major compounds in the extracts. The results obtained from this study show that it is possible to optimize antioxidant capacity in barley grains during roasting.

To make more effective use of underutilised resources, collagens from skin, scale and bone (SKC, SCC and BOC) of deep-sea redfish were isolated with acetic acid and characterised for their potential in commercial applications. The abundant ash and fat in the materials could be removed effectively by EDTA and hexane treatment in 24 h, with high recoveries of protein. The yield of SKC (47.5%) was significantly higher than that of SCC and BOC (6.8% and 10.3%, respectively). The denaturation temperatures of SKC, SCC and BOC were 16.1 °C, 17.7 °C and 17.5 °C, respectively, which were lower than those of most other fish species. The amino acid profiles of these collagens were similar with a low imino acid content, which might be the reason for the low denaturation temperature. All the collagens were type I mainly and maintained their triple helical structures well with slight molecular structure differences. SKC possessed a higher degree of intermolecular cross-linking and molecular order, but the extent of peptide chain unwinding was also higher, due to the existence of fewer hydrogen bonds, compared to SCC and BOC.

The antioxidant and antitumor activities (in vitro) of superfine regular and Se-enriched green tea particles with different sizes (3.52 µm and 220 nm) were investigated in this paper. The vitamin C and tea polyphenol contents of green tea in different sizes were significantly different, and amino acid and chlorophyll just changed a little. The antioxidant activity of green tea particles was evaluated by DPPH radical scavenging and linoleic acid peroxidation inhibition methods, and the antitumor activity was evaluated by antiproliferation assay on HepG2, A549, and MGC803 cells. The results indicated that enrichment of selenium endowed green tea with higher antioxidant activity and antitumor activity on HepG2 and A549 cells but not on MGC803 cells. The DPPH radical scavenging rates of regular and Se-enriched green tea of 220 nm (67.87% and 69.49%, respectively) were significantly greater than that of 3.52 µm, but the inhibition of linoleic acid peroxidation for green tea of 220 nm was lower. The inhibitory rates of green tea of 220 nm on HepG2, A549, and MGC803 cells achieved 77.35%, 80.76%, and 87.54% for regular green tea, and 82.51%, 88.09%, and 74.48% for Se-enriched green tea at the dose of 100 µg mL−1, values that were all significantly higher compared to that of 3.52 µm.

Previously, the antioxidant activity of Se-enriched green tea extracts has been studied in vitro. In the present study, an in vivo micronuclei test was employed to assess the antimutagenic effect of microsized Se-enriched green tea powder (MSTP) in mice bone marrow. Pretreatments of MSTP, micrometer-sized regular tea powder (MRTP), selenite, and MRTP + selenite were given by gavage for 29 consecutive days prior to cyclophoshamide (CP) treatment. Certain key antioxidant enzymes were also investigated to elucidate the mechanism of antimutagenic effect. Results indicated that MSTP and MRTP or selenite alone did not significantly induce micronuclei at either concentration, confirming its nonmutagenicity. In the CP-treated groups, significant suppressions in the micronuclei were recorded following pretreatment with MSTP, MRTP, and selenite administration. The antimutagenic effect of MSTP was evidently observed by significant reduction in the frequencies of micronuclei in bone marrow cells when compared to a positive control group. The administration of MSTP, selenite, and MRTP + selenite also increased the levels of selenium concentration, glutathione peroxidase (GPx), and superoxide dismutase (SOD) enzymes in both blood and liver. However, no pronounced differences in activities of GPx and SOD were found among MSTP, selenite, and MRTP + selenite. The present findings demonstrate that the antimutagenic potential of MSTP could not be solely related to the enhancment of antioxidant enzymes of GPx and SOD.

Ultrafiltration membranes of different pore size were applied to fractionate Chlorella pyrenoidosa polysaccharides (CPPS) and the main fraction could be separated by a membrane with nominal molecular weight cut-off (NMWCO) of 30 kDa. Ultrafiltration parameters of 40 °C 14.0 psi were optimized for obtaining the main fraction. The resulting sample was further purified by anion-exchange chromatography and size exclusion chromatography, and two distinctive polysaccharides, CPPS Ia and IIa were recovered. CPPS IIa had infrared spectral characteristic of polysaccharides similar to CPPS Ia, and the symmetrical stretching peak at 1408–1382 cm−1 was an indication of the presence of carboxyl groups. The peak molecular weights were 69658 Da and 109406 Da, for CPPS Ia and CPPS IIa, respectively. Both CPPS Ia and IIa were composed of rhamnose, mannose, glucose, galactose and an unknown monosaccharide. Galactose (relative mass 46.5%) was the predominant monosaccharide of CPPS Ia and in CPPS IIa, rhamnose (37.8%) was predominant. CPPS Ia and IIa presented significantly higher antitumor activity against A549 in vitro than did a blank control, in a dose-dependent manner. Both fractions might be useful for developing natural safe antitumor drugs from C. pyrenoidosa resources.

Supercritical CO2 extraction of antioxidants from Spirulina platensis was optimized using response surface methodology. About 10.26 g/kg of extracts from S. platensis could be obtained under the optimum conditions of 48 °C at 20 MPa over a 4 h period. The antioxidant activity of the extracts prepared under the optimized condition, determined by linoleic acid peroxidation inhibition method, was lower compared with BHT and Trolox, but significantly higher than α-tocopherol in 300 min and became similar to α-tocopherol after that. The components of the extracts were further analyzed, and the results showed that the extracts contained 85.1 g/kg of flavonoids, 77.8 g/kg of β-carotene, 113.2 g/kg of vitamin A and 3.4 g/kg of α-tocopherol, which may contribute greatly to their high antioxidant activity. The main fatty acids in the extracts were palmitic acid (35.32%), linolenic acid (21.66%) and linoleic acid (20.58%).

The conditions for extracting and purifying polysaccharides from Chlorella pyrenoidosa, including intensity and duration of ultrasound, the temperature and incubation time, and ethanol concentration, were investigated through an orthogonal design of L16(45) in this work. High performance liquid chromatography (HPLC) and gas chromatography (GC) were used to characterize the compounds in C. pyrenoidosa. The highest yield of 44.8 g kg−1 was achieved at 400 W of ultrasound for 800 s and then followed by incubation in water bath at 100 °C for 4 h in 80% ethanol. Two polysaccharide fractions (S1 and S2) were separated from the extracts of C. pyrenoidosa using Sepharose 4B column chromatography. The average molecular weights (Mw) of S1 and S2 were 81,877 Da and 1749 Da, respectively. Gas chromatographic (GC) traces of the hydrolyzed polysaccharides showed that most of the majority of monosaccharide in both fractions was mannose (78.0% and 76.5% of relative mass from S1 and S2, respectively) with low levels of glucose (13.2% and 8.4% of relative mass from S1 and S2, respectively). The Fourier-transform infrared spectra (FT-IR) of S1 and S2 revealed typical characteristics of polysaccharides. Both samples had the characteristics of hydroxyl groups, weak C–H band and α-pyranoses; however, only S2 had a carboxyl group.

The residue levels of four hexachlorocyclohexane (HCH) isomers (α-HCH, β-HCH, γ-HCH and δ-HCH), 4 dichloro-diphenyl-trichloroethane (DDT) congeners (p,p-DDE, o,p-DDT, p,p-DDD, and p,p-DDT), heptachlor, heptachlor epoxide, aldrin, dieldrin and endrin in rice and its bran from Jiangsu Province, PR China, were investigated by simplified two-dimensional gas chromatography, coupled with micro-electronic capture detector (μECD). Concentrations of organochlorine pesticides (OCPs) for ∑HCH ranged from 0 to 0.039 mg kg−1 in the rice and 0 to 0.057 mg kg−1 in its bran. For ∑DDT, the concentrations ranged from 0 to 0.053 mg kg−1 in the rice and 0 to 0.051 mg kg−1 in its bran. The five other OCPs, except HCH and DDT, were not detected. The major HCH isomers and DDT, congeners detected, both in the rice and its bran, were β-HCH and p,p′-DDE. Compared with the residue levels in the rice, the OCPs levels in fish and human fat were detected at higher residue levels. It is necessary to investigate the OCP residues in foodstuffs of the food chain in order to evaluate the potential health risk to humans.

Antioxidant activities of ethanol and petroleum ether extracts from Brazilian propolis were determined by α,α-diphenyl-β-picrylhydrazyl (DPPH) radical-scavenging and ferric thiocyanate (FTC) methods, using α-tocopherol and butylated hydroxytoluene (BHT) as references. The DPPH assay showed that ethanol extract possessed significantly higher activity compared with BHT and petroleum ether extract but lower than that of α-tocopherol. Results from the FTC assay indicated that the activity of ethanol extract was higher than that of α-tocopherol and petroleum ether extract but lower than BHT. Basically, this antioxidant activity was dose-dependent and ethanol extract exhibited higher activity than that of petroleum ether extract at the same concentration. Additionally, the chemical constituents of propolis were determined, and results showed that the propolis contained high content of antioxidant compositions, such as flavonoids (73.00 g kg−1), total phenolic compounds (134.40 g kg−1), and Vitamin E (0.16 g kg−1), which contributed greatly to its strong antioxidant activity.

The crude tea polyphenols, polysaccharides and proteins of regular green tea and Se-enriched green tea were investigated in vitro for antioxidant activities by auto-oxidation test (AAPH) and α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging method. Results showed that crude tea polyphenols of Se-enriched green tea provided the highest antioxidant activity by DPPH assay and the antioxidant activity was decreased in the order: crude tea polyphenols > crude tea proteins > tea polysaccharides. The crude protein of Se-enriched green tea was found to exhibit the highest antioxidant activity by AAPH method and the antioxidant activity was decreased in the order: crude tea proteins > tea polyphenols > tea polysaccharides. Tea polyphenols and tea polysaccharides of Se-enriched green tea presented significantly higher antioxidant activities than that of regular green tea. No significant difference of antioxidant activities was found between crude tea proteins of Se-enriched green tea and regular green tea. The combinations of Se with tea polyphenols and tea polysaccharides were responsible for the higher antioxidant activities of Se-enriched green tea than regular green tea.

The antioxidant activities of brown pigment, extract of n-hexane and extract of supercritical carbon dioxide extraction of black sesame seeds were investigated in this study. Kinetics of anti-radical activity showed that the reaction between DPPH and brown pigment of sesame seed was rapid and reached the steady state in 10 min. Extracts from supercritical carbon dioxide extraction and n-hexane extraction reacted with DPPH slowly and the absorbance became stable after 35 min. However, α-tocopherol and trolox were rapid while the kinetic behaviour of BHA was intermediate. The brown pigment of sesame seed also showed a lower EC50 (13.5 μg ml−1) than the other two extracts and α-tocopherol, which was about 7–10 fold of the antioxidant activity of the supercritical carbon dioxide extract and the n-hexane extract. The ferric thiocyanate (FTC) method also showed that the brown pigment of sesame seed provided higher inhibition activity against lipid peroxidation at 200 μg ml−1 than did the supercritical carbon dioxide extract an n-hexane extract at 1 mg ml−1. However, the activities of the supercritical carbon dioxide extract and n-hexane extracts were significantly higher than that of α-tocopherol. In the linoleic acid system, the brown pigment of black sesame seed showed an equal antioxidant activity to BHA and higher than trolox and α-tocopherol. The results indicated that the brown pigment of sesame seed possessed excellent antioxidant activity.

The free radical-scavenging activities of extracts of Aloe vera of leaf skin by supercritical CO2 extraction and solvent extraction were determined. An orthogonal array design matrix of L9 (34) was considered to optimize supercritical carbon dioxide extraction processing at a CO2 flow rate of 12–36 l h−1, 35–45 MPa and 32–50 °C. The optimum extracted yield of 1.47% was provided at 50 °C 36 l h−1, 35 MPa and 20% of modifier of methanol. These four factors were all demonstrated to be significantly crucial in the supercritical carbon dioxide extraction operation, as two-variable interactions. The extracts of A. vera rind by supercritical carbon dioxide extraction and solvent extracts provided significantly higher free radical-scavenging activities of 33.5% and 39.7%, respectively, than extracts of A. vera gel extracted by ethanol with a free radical-scavenging activity of 14.2%. The inhibition percentage of extracts of A. vera and reference antioxidants followed the decreasing order: Trolox (76.8%) > ethanol extracts of A. vera skin (39.7%) > BHT (35.9%) > the extract of supercritical carbon dioxide extraction (33.5%) >α-tocopherol (25.6%) > ethanol extracts of A. vera pulp (14.2%). Compared to BHT and α-tocopherol, the extracts of A. vera skin, by supercritical carbon dioxide extraction and ethanol, showed stronger antioxidant activities. Components in the rind of A. vera are responsible for the higher antioxidant activity of A. vera extracts.

•A new packaging material was prepared and used for the preservation of Flammulina velutipes.•The nanocomposite-based packaging material (nano-PM) had better effect on barrier property and antibacterial activity.•The nano-PM had better fresh-keeping effect than the normal packaging material.•The storage time of F. velutipes packaged with nano-PM can be extended to more than 14 days.In this study, a polyethylene (PE) packaging material that contained nano-Ag, nano-TiO2, nano-SiO2, and attapulgite was prepared and its effect on storage stability of mushrooms (Flammulina velutipes) was investigated. The results showed that the nanocomposite-based packaging material (Nano-PM) regulated oxygen and carbon dioxide level, eliminated ethylene and inhibited the growth of microbes, which is a benefit on preservation quality of mushrooms, compared to the normal PE material (Normal-PM). After 14 days of storage, mushroom weight loss, mushroom cap opening, stipe elongation and respiration of Nano-PM stored mushroom were significantly (P < 0.05) inhibited. Furthermore, treatment with the Nano-PM improved the retention of vitamin C, soluble protein, and total soluble solids contents of F. velutipes. The results therefore are promising for the preservation of F. velutipes in order to expand its shelf life and improve its preservation quality by use of this Nano-PM.Industrial relevanceFlammulina velutipes, also named as golden needle mushroom, is one of the most popular edible mushrooms worldwide. Its production and consumption ranked the fourth place among all edible mushrooms in the world. However, fresh golden needle mushrooms are highly perishable. Therefore, preserving freshness of the mushrooms is the main objective of postharvest technology. In the present study, we developed a new type of effective and economic nanoparticle packaging materials and applied it to mushroom preservation. A local company (Jiangsu Tianfeng Biological Technology Co., Ltd) producing mushrooms has started to use this nano-preservation technology during the postharvest transportation and sales. In conjunction with the results of present research, we suggests that nano-composite based packaging materials is a good way for preserving fresh mushrooms and has the potential to be commercialized.

The anticlastogenic effect of micrometer powder of selenium-enriched green tea (MSTP) was evaluated by using a chromosomal aberration assay in mouse testicular cells. Animals fed with a Se-deficient diet were treated with MSTP, micrometer powder of regular green tea (MRTP), selenite, and MRTP + selenite for 30 days by an intragastric route, followed by treatment of mitomycin C (MMC) on day 19 through intraperitoneal injection (ip). Selenium status and antioxidant enzymes were measured. Results indicated that MSTP showed a significant capability to reduce the incidence of MMC-induced chromosomal aberrations in spermatocytes from 22.7% to 6.7%. This inhibitory was highest, for MSTP, at 73.1%, while it was only 38.4% for MRTP. After 30 days of a Se-deficient diet, mice, either with or without the MMC treatment, showed a lower selenium concentration in blood and liver as well as lower enzyme activity of the antioxidants, GPx and SOD. Supplementation with MSTP, selenite, or selenite + MRTP enhanced the activities of these antioxidant enzymes. This enhancement was accompanied with a concomitant elevation of selenium levels, which favored the synthesis of the seleno-enzyme GPx and protected the cells from the MMC-induced oxidative stress. Our results indicate that MSTP is both able to prevent the chromosomal aberrations induced by MMC in mouse spermatocytes and to enhance GPx and SOD activity in blood serum and liver.

Ethnopharmacological relevancePleurotus eryngii (DC. ex Fr.) Quel has been collected from the wild, cultivated and used in traditional medicines to treat various disorders and diseases since antiquity. In traditional Chinese medicine, the powdered fruiting bodies of Pleurotus eryngii were used for immunostimulation, skin-care, wound-healing, cancer and lumbago treatment. In the current study, we investigated the antiproliferative activity of Pleurotus eryngii powder on A549, BGC-823, HepG2 and HGC-27 cancer cells and its immunomodulating activity on macrophage, RAW 264.7 cells based on its active compound.Materials and methodsA novel bioactive protein (PEP) was extracted from Pleurotus eryngii fruiting bodies powder and purified on DEAE-52, CM-52 and Superdex 75 column chromatographies using an ÄKTA purifier. Its cytotoxicity on A549, BGC-823, HepG2, HGC-27 and RAW 267.4 cell lines was then evaluated using MTT, alamar blue (AB), trypan blue (TB), neutral red (NR), lactate dehydrogenase (LDH), Annexin V FITC/PI and morphological change assays. Moreover, lysosomal enzyme activity, pinocytosis, nitric oxide (NO) and hydrogen peroxide (H2O2) production assays were used to examine immunomostimulatory activity of PEP on RAW 267.4 cells.ResultsBased on high performance gel permeation chromatography (HPGPC), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses, the isolated protein (PEP) had a molecular weight of 63 kDa, a secondary (α-helical) structure and was mainly composed of arginine, serine and glycine. PEP significantly (P<0.05) inhibited A549, BGC-823, HepG2 and HGC-27 tumor cells proliferation dose-dependently with an IC50 range of 36.5±0.84 to 229.0±1.24 µg/ml. Contrarily, PEP stimulated the proliferation of macrophages.ConclusionPleurotus eryngii fruiting bodies powder has a potential application as a natural antitumor agent with immunomodulatory activity, proposedly, by targeting the lysosomes of cancerous cells and stimulating macrophage-mediated immune responses.Download high-res image (276KB)Download full-size image

Se-enriched rice was prepared by foliar fertilization. In the present work, speciation and distribution of Se in Se-enriched rice and non-supplemented rice was evaluated by ion-paring reversed phase (IP-RP) and strong anion-exchange (SAX) chromatography coupled with inductively coupled plasma mass spectrometry (ICPMS) detection. Three extraction procedures: water extraction, acid extraction (0.1 M HCl) and enzymatic hydrolysis were studied with a combination of protease XIV and amylase with ultrasonic bath and the latter was found to be optimal for the extraction of selenospecies. The chromatograms obtained revealed that the major selenospecies found in Se-enriched rice was selenomethionine (SeMet), which was further identified by nanoelectrospray ionization, ion trap mass spectrometry (nano-ESI-ITMS). Approximately 86.9% of the total Se in the Se-enriched rice extract was SeMet, while only 26.7% of non-supplemented rice extract was due to SeMet. Moreover, nearly 60% of inorganic Se in the form of SeIV was present in the non-supplemented rice, while only 6.8% of inorganic Se as SeIV and SeVI was found in Se-enriched rice extract with minor selenocystine (SeCys2) and trace selenomethionine selenoxide (SeOMet) present. The results proved that SeMet was efficiently extracted by the enzymatic hydrolysis without oxidization. The high SeMet concentrations of Se-enriched rice indicate a high inorganic to organic conversion when Se enrichment was carried out by foliar application. Since SeMet is a readily bioavailable Se species for animals, Se-enriched rice could be considered for supplementation in Se poor geographical regions.