Abstract:The feijoa, Feijoa sellowiana (O. Berg), is a perennial evergreen shrub of the Myrtaceae family, which originates from the South America and is grown in the subtropical region. It is a food crop of medicinal and nutritional value. It has a brilliant prospect in food, nutraceutical, pharmacology and cosmetic industries. This review summarized the international studies on the nutraceutical value, recent applications and developments of the nutritional and bioactive products from feijoa fruit (including pulp, peel and its waste) and its leaves and twigs. The developments of feijoa in domestic market were also discussed.

Abstract:Plant gelatin-carrageenan is a sulfated polysaccharide and is widely used in food and pharmaceutical industries, especially for capsule shells. The article reviewed the extraction of gelatin-carrageenan from marine plants with the emphasis on four key steps, including alkali pretreatment, acidified bleaching, extraction and dehydration. This would help in the future research and production of plant gelatin-carrageenan.

Abstract:The molecular mechanism for the binding sites, driving forces and the interaction intensity between sialyltransferase (ST) and soyasaponin I was investigated by molecular docking and free energy calculation based on the crystal structure. The van der Waals force and electrostatic interaction were considered as the main driving forces, while polar solvation energy behaved in an opposite manner. The hydrophobic interaction was formed between soyasaponin I and eight amino acid residues, i.e., Gly149, Ser151, Met172, Asn173, Phe292, Trp300, His301, and Ser325. Hydrogen bonding was found between soyasaponin I and eleven amino acid residues, including Asn150, Tyr194, Ser271, Thr272, Gly273, Ile274, Gly291, Gly293, His302, Glu305, and Glu324. Soyasaponin I was a competitive inhibitor which occupied 11 of the 12 amino acid residues that accommodated the substrate CMP-β-N-acetylneuramic acid. These results provide a theoretical basis for the development and utilization of soyasaponin I as a ST inhibitor.

Abstract:8 lactobacillus reuteri were isolated from camel rumen and then cultured in mineral saults medium using pyridine (300 μg/mL) as the sole carbon source and nitrogen source. The absorbance at 600 nm was periodically measured by UV spectrophotometer to check the growth of Lactobacillus. The degradation of pyridin by lactobacillus reuteri was dynamically detected using Gas Chromatography-Mass Spectrometry (GC-MS) and the residual amount after degradation was calculated. According to the results, all the lactobacillus could effectively degraded pyridine, among which GU366027 and GU366021 can completely degraded pyridine when cultured for 84 h, while GU366034, GU366019 and U366030 needed 96h and others (GU366037, GU366038, GU366028) for 108 h.

Abstract:Using a mice monoclonal antibody and a rabbit polyclonal antibody of the watermelon mosaic virus (WMV)-2 coat protein, we developed two detection methods for WMV-2. The trimer antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) method was established based on two different antibodies; the electrochemical paper assisted immunosensor detection method was established by combining the electrochemical workstation with the paper assisted immunosensor prepared by the carbon nanotube and the antibody-coated filter paper. The detection limit was 0.15 and 0.2 μg/ml, and the testing time was 3 hours and 30 minutes for two methods, respectively. According to these results, the TAS-ELISA method had a higher detection sensitivity, and the electrochemical paper assisted immunosensor detection method had a shorter testing time.

Abstract:Wheat protein was hydrolyzed by proteases Flavourzyme, Neutrase and Protamex with Flavourzyme being the best for the production of precursors of bread flavor and the maximum degree of hydrolysis (DH). Based on orthogonal experiments the optimum hydrolysis parameters were: substrate concentration, 5%; Flavourzyme concentration, 2 000 U/g; pH, 7.0； temperature, 50 ℃; time, 2.5 h. Under the condition, a DH of 35.50% was reached and Maillard reaction products as the optimum precursors of bread flavor were obtained. The hydrolysate contained 5.24 and 3.91 mg/mL more amino acids for bread flavor, 7.42 and 4.45 mg/mL more total free amino acids, 6.79 and 1.59% higher contents of the portion with the molecular weight (MW) below 3 861, and 12.34 and 3.34% higher contents of the portion with the MW below 1405Da than those of 0.5 h and 1.5 h, respectively. The portion with the MW below 3861Da was favorable to the Maillard reaction. SPME/GC-MS analysis proved that the Maillard reaction products formed the key bread flavor. This paper encourages the further study for the production of bread flavor compounds via the Maillard reaction.

Abstract:The synergistic effect of feruloyl esterase and cellulose on the release of ferulic acid from de-starched wheat bran (DSWB) was studied. The HPLC results showed that DSWB which was ultrasonically pretreated at a power of 350?W for 20 minutes released ferulic acid at a level of 1.45-fold more than that unpretreated. ReAoFaeA (30 U) by itself released only 4.1% of total alkali-extractable ferulic acid from wheat bran, while no ferulic acid released if rAuCel12A was used. The rate of ferulic acid released was significantly increased when both enzymes were used. The conditions using two enzymes simultaneously were optimized by a single factor test. A maximum of 23.6% total ferulic acid released could be reached in combinations of 30 U reAoFaeA and 70 U rAuCel12A with the ratio of solid to liquid of 1∶30 (g∶mL) at pH 5.0 and treated under 40 °C for 10 h.

Abstract:Effects of several mixed natural polyphenol oxidases (PPO) on the transform of tea polyphenols into theaflavins were compared in this paper. Results showed a ranking of pear and potato PPO＞pear PPO＞pear and yam PPO＞pear and apple PPO＞pear and sweet potato PPO for the oxidative activities of five enzyme systems. The pear and potato PPO mixture also led to a higher content of theaflavins (88.13%) than the pear PPO (76.95%). So the mixed pear and potato PPO system is optimal for the oxidation of tea polyphenols.

Abstract:An electronic nose was used to characterize and classify different volatile components of sweet persimmon according to times of storage. Principal component analysis (PCA) and linear discrimination analysis (LDA) were respectively used for data process, and the response changes of the primary sensor were mainly analyzed by loadings analysis. LDA results indicated that sweet persimmon stored under different conditions, i.e, room temperature storage (18～20 ℃) and storage after postharvest (18～20 ℃ after stored under 0±1 ℃ for 40 d), was discriminated more effectively than those under cold storage (0±1 ℃). Sensors of W2S (ethanol) and W1W (terpene) played important roles in discrimination of sweet persimmon with different shelf life under either room temperature or cold storage, while sensors of W2W (aroma constituent and organic sulfide) and W1W (terpene) contributed for discrimination of those stored after postharvest. Therefore, electronic nose is an efficient device for rapid discrimination of sweet persimmon stored under different conditions.

Abstract:ompetitive enzyme-linked aptamer assay for Ochratoxin A (OTA) detection in wine was investigated in this study. The binding of aptamer to the target OTA resulted in the dissociation of the DNA short chain from the aptamer, which was further captured by horseradish peroxidase (HRP). HRP catalyzed 3,3',5,5'.-Tetramethylbenzidine (TMB) substrate and finally leaded to a characteristic change that was detectable by the absorption of ultraviolet at 450 nm. The detection limit of OTA was determined by the linear relationship between OTA concentration and the absorbance. The factors influenced the effect of detection were investigated, including DNA concentration, temperature of hybridization, and blocking buffer solution. This work described the high performance of the competitive enzyme-linked aptamer assay (ELAA) for the determination of OTA. Under the optimal condition, the limit of detection attained was 0.88 μg/L and the linearity was in the range 1 to 100 μg/L. For the OTA detection in wine, the recovery rate was between 92.03% and 106.6%, and the relative standard deviation (RSD, n=5) was within 2.1%. This study validates the competitive ELAA is a useful tool for a rapid detection of OTA in wine.

Abstract:The key processing technology of fresh lettuce including, pre-cooling, cutting, sterilization, preservation, centrifugal dehydration, modified atmosphere packaging (MAP) and storing. Respiration intensity and sterilization effect were determined to optimize the process parameter of the preservation and sterilization. The results showed that the fresh lettuce treated with pre-cooling for 12 hours under 10 ℃, 60 mg/L acetic acid, 50 mg/L peroxyacetic acid and 20 mg/L H2O2 for 2 minutes, 0.2% citric acid and 6% calcium ascorbate for 2 minutes, then centrifugal dehydration and MAP with 4%O2, 5%CO2 and 91% N2. The shelf life of the fresh lettuce would be 10 days under 10 ℃.

Abstract:The accidents caused by gelatin have received extensive attention recently. This study aimed to make pectin a viable replacement of gelatin. In the study, pectin/chitosan /konjacgum composite membrane was prepared by solution blending with different mass ratios. The membrane was characterized by IR、XRD and DSC to detect its swelling degree, water vapor permeability (WAP), light transmittance, in vitro degradation, and antimicrobial activity. The results indicated that pectin and chitosan were compatible and interacted with each other. The composite membrane had the lowest water vapor transmittance and relatively low air permeability if their mass ratio was 1∶1, where the swelling degree could be reached 48.7%. Meanwhile, the membrane showed a good in vitro degradation and antimicrobial properties. The composite membrane prepared under the optimal condition has great potential as capsule packaging materials and edible packaging materials.

Abstract:The reduction of tropomyosin (Tm), the major allergen in Pacific white shrimp (PenaeusVannamei), was studied using enzymolysis and the combination of ultrasound andenzymolysis, respectively. First, the enzymatic hydrolysis of shrimp Tm with bromelain was optimized by measuring the effects of changes in enzyme activity/substrate mass ratio, incubation time and temperature of hydrolysis. The changes of Tm allergenicity in peeled prawns, butterfly shrimp and minced shrimp was comparatively studied by three methods of hydrolysis. The antiserum of sensitization animal model for shrimp allergen Tm was detected using enzyme-linkedimmunosorbent assay (ELISA). The results showed the allergenicity was not significant (P>0.05) when treated with enzymolysis or combining with ultrasound. The allergenicity of the butterfly shrimp treated by ultrasound and bromelain was reduced to 21.05%, while the allergens of the minced shrimp hydrolyzed using enzymolysis or the combination of ultrasound andenzymolysiswere reduced to 30.70% and 33.33%, respectively. In conclusion, the developed enzymolysis methods, ie., the enzymolysis and the combination of ultrasound andenzymolysis, can effectively reduce shrimp Tm allergenicity. They have potential applications in producing hypoallergenic shrimp, such as hypoallergenic butterfly shrimp or hypoallergenic minced shrimp.

Abstract:Panax ginseng and Panax quinquefolius are two important traditional Chinese medicine with similar morphology but different medicinal efficacy. This study aimed to develop a simple and effective analysis of molecular authentication of Panax ginseng and Panax quinquefolius. Two allele-specific primers of Panax ginseng and Panax quinquefolius were designed from their Single Nucleotide Polymorphism (SNP) created by ribosomal DNA (rDNA) external transcribed space (ETS). Multiplex polymerase chain reaction (Multiplex PCR) was conducted for identification of Panax ginseng and Panax quinquefolius. The results confirmed the effective authentication of Panax ginseng and Panax quinquefolius as well as their mixture by the established PCR method.

Abstract:Hydrolysis of egg white by Flavourzyme was determined by the orthogonal test. The optimum parameters were: temperature, 55 ℃; pH, 6.5; enzyme dosage, 6%; egg white concentration, 1∶5. With the condition, the residual protein rate and the degree of hydrolysis after 6 h were 27.68% and 38.75%, respectively, and the resulting hydrolysate primarily consisted of free amino acids and dipeptides.

Abstract:Phospholipids have been widely used in the food and pharmaceutical industries. The adsorption is generally employed to separate and purify phospholipids. The static adsorption of phosphatidyl ethanolamine in egg yolk onto alumina was investigated and the kinetics and thermodynamics of the adsorption were studied using the high performance liquid chromatography. The fit model of the adsorption in phospholipids/methanol solution was the second-order kinetic model, where the internal diffusion was the key control of the adsorption but not the only one. The isothermal adsorption can be well explained using Langmuir Adsorption Isotherm. The adsorption process was a spontaneous exothermic process resulted from the increase in the systems entropy.

Abstract:The anti-aging effects and mechanisms of ellagic acid from pomegranate have been studied. Firstly, free radical scavenging activity of ellagic acid was determined according to the elimination of DPPH ·OH and ·O2- radicals by spectrophotometry as well as the elastase inhibition activity. Secondly, the mechanism of interaction between ellagic acid and elastase was investigated with fluorescence spectra. An 88.26% inhibition rate could be reached when the ellagic acid-elastase complex was formed if the concentration of ellagic acid was 4.57 mg mL-1. The fluorescence quenching of elastase when interacted with ellagic acid was regarded as a static quenching when the concentration of ellagic acid was lower than 4.0×10-5 mol L-1. The dynamic quenching increased when raised the ellagic acid concentration. Ellagic acid, a natural free radical scavenger and inhibitor, has great potential in the cosmetics industry as an anti-aging ingredient.

Abstract:Debranching enzyme was used to enhance the extraction efficiency and product quality of rice protein. A significant decrease in molecular weight was detected by HPSEC for rice starch digested by debranching enzyme and the 1H-NMR analysis proved that the enzyme completely hydrolyzed α-1,6-linkages, which facilitated the following function of glucoamylase. Debranching enzyme together with α-amylase and glucoamylase could entirely hydrolyze the dextrin in liquefied rice dreg after sugar processing into water soluble oligosaccharides, which increased the removal rate by 38.9% compared with the processing only through glucoamylase. The total nitrogen content of the crude protein reached up to 90.58%, which was higher than that obtained by the traditional methods.