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关键词： Soluble proteins   Microalgae biorefinery   Bead milling   Membrane filtration   Physicochemical conditions  

摘要： Chlorella vulgaris proteins show high potential for food applications. The challenge of biorefinery is to choose the best processes coupling which can ensure the integrity of the molecules and limit energy consumption. This study aimed at understanding the impact of biomass concentration and physicochemical conditions during cell disruption, on the whole process (bead milling (BM), centrifugation, microfiltration). The best scenario tested (BM: 60 g/LDW, 10 degrees C, lysate dilution: 30 g/LDW, pH 7, 20 degrees C before centrifugation and filtration of the supernatant at a volume reduction ratio VRR = 3) allowed a soluble protein recovery eta S = 12 % with a limited energy consumption of 10 kW h/g protein. Coupling BM at 90 g/LDW, pH 7, a dilution at 20 degrees C, with NaCl 0.1 M at 30 g/ LDW and filtration at VRR = 20 would lead to eta S>25 %. The final soluble proteins contained no green pigment;their purity increased from 5 % in the raw biomass to 22 % in the permeate.

关键词： Acid-hydrolyzed starch   Starch-fatty acid mixtures   Pasting properties   Carbohydrate radicals  

摘要： The aim of this paper was to evaluate the effect of acid hydrolysis on formation of the starch-oleic acid mixtures, their structure and functional properties. The potato starch was hydrolyzed with hydrochloric acid for 0.5?4.0 h, then obtained acid-hydrolyzed starches were mixed with oleic acid to prepare the starch-oleic acid mixtures. Measurements of molecular size distribution, lipids content, fatty acid composition, and complexing index of gelatinized mixtures revealed that performed modifications were effective. The water binding capacity at 80 ?C of tested starch-fatty acid mixtures ranged from 14.51 (g/g) for untreated potato starch to 11.24 (g/g) for starch hydrolyzed for 4 h. The addition of oleic acid reduced the solubility in water at 80 ?C of modified starches by 7061% compared to their counterparts. The highest DPPH radical scavenging activity (15.1%) was found for the starch hydrolyzed for 0.5 h and mixed with oleic acid. Hot paste and final viscosities of the starch-fatty acid mixtures gradually decreased with the increasing of acid treatment time. The lowest values of these parameters were determined in mixture of starch hydrolyzed for 4 h (364 mPa s and 536 mPa s, respectively). Incorporation of oleic acid into starch hydrolyzed for 4 h increased by approximately 90% content of the resistant starch fraction compared to the non-mixed counterpart. Electron paramagnetic resonance studies showed that acid hydrolysis promoted the generation of stable carbon centered radicals in starch, whereas the introduction of oleic acid strongly inhibited this process.

关键词： Charge variants   Fractionation   Similarity   Bevacizumab   Analytical characterization  

摘要： The majority of recombinant mAb products contain heterogeneous charge variants, commonly the result of post-translational modifications occurring during cell culture and accumulated during production, formulation and storage. MB02 is a biosimilar mAb to bevacizumab. Similarity data of charge variants for biosimilars against its reference products must be generated to demonstrate consistency in product quality and to ensure efficacy and safety. The goal of this work was to isolate seven charge variants of MB02 and Avastin (R) by semi-preparative cation exchange chromatography followed by purity test and extended analytical characterization to prove similarity. Although poor purity obtained for minor variants complicated data interpretation, an in-depth insight into the charge variants pattern of MB02 compared to Avastin (R) was obtained, contributing to a better under-standing of modifications associated to microheterogeneity. To our knowledge, this is the first comparative analytical study of individual charge variants of a bevacizumab biosimilar following a head-to head approach and the most comprehensive N-glycosylation assessment of IgG1 charge variants. Although modifications related to N-and C-terminal, N-glycans, size heterogeneity or deamidation were specifically enriched among low abundant charge variants, they did not affect binding affinity to VEGF or FcRn and in vitro potency compared with the main species or unfractionated material.

关键词： Sporopollenin   Folic acid   Encapsulation   Controlled release   Photoprotection  

摘要： Folic acid (FA) is a crucial vitamin for all living creatures. However, it is susceptible to degradation under pH, heat, ultraviolet (UV) and day sunlight conditions, resulting in lowering its bioavailability. Therefore, a versatile protective encapsulation system for FA is highly required to overcome its inherent instability. We report the use of the robust Lycopodium clavatum sporopollenin (LCS) microcapsules, extracted from their natural micrometersized raw spores, for FA microencapsulation. The physico-chemical characterisation of the LCS microcapsules are comprehensively investigated before and after the microencapsulation using SEM, elemental, CLSM, FTIR, TGA/ DTG and XRD analyses, revealing a successful FA encapsulation within the LCS in an amorphous form. The phenylpropanoid acids, responsible for the UV protection and the autofluorescence of the LCS, were found in the LCS as evidenced by FTIR analysis. TGA/DTG results revealed that the hemi-cellulose and cellulose are the major component of the LCS. A controlled and sustained release of FA from FA-loaded LCS were achieved where the release profile of FA-loaded LCS was found to be pH-dependent. The percentages of cumulative FA released after 10 h at 37 +/- 0.5 degrees C were 45.5% and 76.1% in pH 1.2 and 7.4, respectively, ensuring controlled and slow release in simulated physiological conditions. The FA release kinetic studies indicated the prevalence of the Fickian diffusion mechanism in pH 1.2, while anomalous non-Fickian transport was ascribed for FA release in pH 7.4. The in vitro cytotoxicity assay revealed that the obtained formulations were biocompatible against the human skin fibroblast (HSF) cell line. The versatile LCS microcapsules exhibited intriguing photostability for FA under UV or sunlight irradiation. Concretely, the obtained FA sustained delivery and photoprotection properties of these LCS microcapsules validate their multifunctional characteristics, opening up intriguing applications in o

关键词： Thawing  

摘要： This study investigated the effects of different thawing methods on the physico-chemical properties and microstructural characteristics of pasteurized milk and concentrated milk. Four thawing methods including air thawing, flowing water thawing, microwave thawing, and ultrasonic thawing (UT) were individually used. The results showed that particle size and fat globules size of milk increased after thawing, but UT could improve these conditions. For the pasteurized milk, thawing process caused ethanol stability and heat stability degradation. Thawing decreased thermal stability of concentrated milk;however, no change was observed in ethanol stability. Secondary structures of proteins in both samples were also destroyed after thawing. The thawing method did not change pH values, but it would cause a small change in titratable acidity. Overall, the UT could maintain physico-chemical properties of pasteurized milk and concentrated milk better compared with other thawing treatments. Practical applications Thawing is an essential step before processing or eating frozen food and can greatly affect the final quality of the frozen food. To our knowledge, no previous study has optimized the method of thawing milk and compared the effects of different thawing methods on milk. So, it is important to study the effect of the different thawing method on the quality of concentrated milk. Ultrasonic thawing can increase the physico-chemical properties of milk.

关键词： coliforms   E   coli   preharvest agricultural water   produce   treatment  

摘要： Aims The presence of foodborne pathogens in preharvest agricultural water has been identified as a potential contamination source in outbreak investigations, driving markets and auditing bodies to begin requiring water treatment for high-risk produce. Therefore, it is essential that we identify water treatment methods which are effective as well as practical in their application on farm. Methods and Results In this work, we evaluated two sanitizers which are most prominent in preharvest agricultural water treatment (calcium hypochlorite (free chlorine: 3-5 ppm) and peracetic acid (PAA: 5 ppm)), an EPA registered antimicrobial device (ultraviolet light (UV)), in addition to a combination approach (chlorine + UV, PAA + UV). Treatments were evaluated for their ability to inactivate total coliforms and generic Escherichia coli and consistency in treatment efficacy over 1 h of operation. Physicochemical variables were measured along with microbial populations at 0, 5, 15, 30, 45 and 60 min of operation. Escherichia coli and coliform counts showed a significant (P < 0 center dot 05) reduction after treatment, with combination and singular treatments equally effective at inactivating E. coli and coliforms. A significant increase (P < 0 center dot 05) in oxidation-reduction potential was seen during water treatment (Chlorine;UV + Chlorine), and a significant reduction (P < 0 center dot 05) in pH was seen after PAA and PAA + UV treatments (60 min). Conclusion Overall, the results indicate that all treatments evaluated are equally efficacious for inactivating E. coli and coliforms present in surface agricultural water. Significance and Impact of the Study This information when paired with challenge studies targeting foodborne pathogens of interest can be used to support grower decisions when selecting and validating a preharvest agricultural water treatment programme.

关键词： ATPase   Glutamine synthetase   Metal   Notorious effect   Toxicity  

摘要： The present study was undertaken to investigate the arsenite (As III)-induced changes in the diazotrophic cyanobacterium Anabaena PCC 7120. It was observed that the growth of cyanobacterial decreased with increase in As (III) concentration. The cells exposed to As (III) showed morphological variation (deformity) due to the formation of deeper constrictions in vegetative cells. Strain showed increased heterocyst differentiation (1.6-fold higher) whereas decreased nitrogenase activity at the concentration of 40 ppm As (III). The activities of NR, NiR, urease and GS decreased with increase in As (III) concentrations and attained their minimum levels at 40 ppm of As (III). The Ca2+-dependent ATPase activity increased with increase in As (III) concentration and attained its about 2.72-fold higher level at 40 ppm of As (III). In contrast, sharp decline in Mg2+-dependent ATPase activity (28%) was recorded at 1 ppm of As (III) over untreated control. The rates of photosynthetic O-2 evolution and respiration decreased with increase in As (III) concentration and attained its minimal level at 40 ppm of As (III). Therefore, this study highlighted arsenite regimes efficiently correlated with behavioral changes in consort with strain.

关键词： Fruits  

摘要： The jambolan (Syzygium cumini) is a purple-colored fruit belonging to the Myrtaceae family. In the post-harvest period, waste is something common due to the high production and perishability, in addition to the acidic and astringent taste that restricts its consumption. Therefore, this study aims to promote the use of jambolan fruit by producing jam using passion fruit albedo as a replacement for commercial pectin. Then, a response surface methodology was used to evaluate the interference of pulp/sugar, citric acid, and passion fruit albedo ratios in the response variables. The jambolan fruit proved to be favorable to jam elaboration. However, the increase in jambolan pulp content promoted a negative impact on the sensory characteristics of jams, such as astringent taste, arenosity, and granularity. With the sensory analysis, it was possible to choose the formulation F2, as the best jam. In addition, the processing of jambolan in the form of jam proved to be a great alternative for the preservation of the fruit for long periods. Practical applications Jambolan is a fruit rich in bioactive compounds, with antioxidant activity, such as anthocyanins, flavonoids, phenolic among others. Although the fruit is not widely used as food, it is necessary to make the population aware of its importance and preservation, not only as a source of nutrients, but also for its functional and sensory potential. Therefore, the production of jambolan jam can increase the consumption of the fruit, moreover being a way to add value and prolong the shelf life and sensory acceptance of the prepared product.

关键词： benzoylhydrazone   cytotoxicity   ethidium bromide   Hirshfeld analysis   nuclease activity  

摘要： A series of dioxidomolybdenum (VI) complexes, [MoO2(ESB)H2O]center dot DMF (1), [MoO2(ESB)MeOH] (2), and [MoO2(ESB)H2O]center dot EtOH (3), containing 3-ethoxysalicylaldehyde benzoylhydrazone have been synthesized and analysed using various spectral and analytical techniques such as elemental analyses, IR spectra, UV-Vis absorption spectra, X-ray crystallography, and Hirshfeld surface analysis. Based on the elemental and spectral analysis, six-coordinate geometry was assigned for these complexes wherein the hydrazone ligand binds to the metal centre in its dianionic enolate form through ONO donor set. Distorted octahedral geometry of complexes 1 and 2 was evidenced from their crystal structures, which is typical for many cis-dioxido complexes of Mo-VI. The proligand and the new complexes were examined for their DNA binding, DNA cleavage, and cytotoxic properties. The DNA binding efficiency of the compounds in terms of their binding constants (K-b) of the metal complexes was observed to be 1.3727 x 10(5) M-1, 3.0194 x 10(4) M-1, and 1.13206 x 10(4) M-1 for [MoO2(ESB)H2O]center dot DMF (1), [MoO2(ESB)MeOH] (2), and [MoO2(ESB)H2O]center dot EtOH (3), respectively, indicating that these complexes strongly bind to DNA. To determine the binding interactions of the complexes with DNA and protein (BSA), molecular docking studies were carried out. Gel electrophoresis study reveals the fact that the complexes cleaved supercoiled pUC-18 DNA to nicked form (Form II) in the presence and absence of H2O2. The complexes showed significantly high cytotoxicity against MCF-7 (breast cancer cells).

关键词： Chinese yam   Polysaccharides   Maillard reaction  

摘要： Dioscorea opposita Thunb., an edible and pharmaceutical plant, is usually consumed after heating processing, such as steaming, boiling, and frying with bran. In order to determine the effect of heating temperature on Maillard reaction products (MRPs) of polysaccharides from Dioscorea opposita (DOP), DOP-MRPs at 90-120 degrees C were prepared. The characterisation including colour, pH, FT-IR, XRD, fluorescence, UV-vis spectroscopy, and volatile compounds by GC-MS and GC-IMS were investigated. Results showed that the major volatile compounds of DOP-MRPs were acids, esters and ketones. Esters were generated the most (approximately 65.80%) at 90 degrees C, and acetic acids were produced approximately 25.70%. According to principal component analysis, flavours in DOP-MRP-90 and DOP-MRP-120 showed significant differences. Additionally, antioxidant activities including hydroxyl radical (HRS), DPPH scavenging and ferric ion reducing antioxidant power (FRAP) were conducted. The DOP-MRP-90 presented highest antioxidant activities, indicating that it donated more hydrogen atom to stabilize free radicals. This study provides a scientific basis for the application of the Maillard reaction in foods for Chinese yam polysaccharides.