Research on Residual-Current Measurement System of Substation Considering Magnetic Shielding Effect.

Residual current is an important monitoring quantity of a power system, and a current sensor plays an important role in detecting current. The substation environment is complex. In addition to the power frequency signal, residual current also has AC and DC components. But it is also affected by the stray magnetic field of the substation. Therefore, the accuracy of the current sensor demands higher requirements. The tunnel magnetoresistive sensor has the advantages of a stable operation, high efficiency, and energy saving, but it is easily affected by the external stray magnetic field during measurements, resulting in a large error. Therefore, this paper proposes a residual-current sensing monitoring system considering the magnetic shielding effect. The root mean square error of the magnetic shielding structure is only 0.572 mA, which can effectively reduce the influence of the external magnetic field and improve the detection accuracy. At the same time, the DC measurement error is less than 1%, the AC measurement error is less than 5%, and the hybrid AC/DC error is less than 8%. It has good response ability and can accurately detect residual current.

Influence of Centrifugation and Transmembrane Treatment on Determination of Polyphenols and Antioxidant Ability for Sea Buckthorn Juice.

When the total phenolic content (TPC) and antioxidant activity of sea buckthorn juice were assayed by spectrophotometry, the reaction solutions were not clarified, so centrifugation or membrane treatment was needed before determination. In order to find a suitable method for determining TPC and antioxidant activity, the effects of centrifugation and nylon membrane treatment on the determination of TPC and antioxidant activity in sea buckthorn juice were studied. TPC was determined by the Folin-Ciocalteau method, and antioxidant activity was determined by DPPH, ABTS, and FRAP assays. For Treatment Method (C): the sample was centrifuged for 10 min at 10,000 rpm and the supernatant was taken for analysis. Method (CF): The sample was centrifuged for 10 min at 4000 rpm, filtered by Nylon 66 filtration membranes with pore size of 0.22 µm, and taken for analysis. Method (F): the sample was filtered by Nylon 66 filtration membranes with pore size of 0.22 µm and taken for analysis. Method (N): after the sample of ultrasonic extract solution reacted completely with the assay system, the reaction solution was filtered by Nylon 66 filtration membranes with pore size of 0.22 µm and colorimetric determination was performed. The results showed that centrifugation or transmembrane treatment could affect the determination of TPC and antioxidant activity of sea buckthorn juice. There was no significant difference (p > 0.05) between methods (CF) and (F), while there was a significant difference (p < 0.05) between methods (C) (F) (N) or (C) (CF) (N). The TPC and antioxidant activity of sea buckthorn juice determined by the four treatment methods showed the same trend with fermentation time, and the TPC and antioxidant activity showed a significant positive correlation (p < 0.05). The highest TPC or antioxidant activity measured by method (N) indicates that method (N) has the least loss of TPC or antioxidant activity, and it is recommended for sample assays.

Preparation of Neohesperidin-Taro Starch Complex as a Novel Approach to Modulate the Physicochemical Properties, Structure and In Vitro Digestibility.

Neohesperidin (NH), a natural flavonoid, exerts multiple actions, such as antioxidant, antiviral, antiallergic, vasoprotective, anticarcinogenic and anti-inflammatory effects, as well as inhibition of tumor progression. In this study, the NH-taro starch complex is prepared, and the effects of NH complexation on the physicochemical properties, structure and in vitro digestibility of taro starch (TS) are investigated. Results showed that NH complexation significantly affected starch gelatinization temperatures and reduced its enthalpy value (ΔH). The addition of NH increased the viscosity and thickening of taro starch, facilitating shearing and thinning. NH binds to TS via hydrogen bonds and promotes the formation of certain crystalline regions in taro starch. SEM images revealed that the surface of NH-TS complexes became looser with the increasing addition of NH. The digestibility results demonstrated that the increase in NH (from 0.1% to 1.1%, weight based on starch) could raise RS (resistant starch) from 21.66% to 27.75% and reduce RDS (rapidly digestible starch) from 33.51% to 26.76% in taro starch. Our work provided a theoretical reference for the NH-taro starch complex's modification of physicochemical properties and in vitro digestibility with potential in food and non-food applications.

Phytochemicals and Antioxidant Capacities of Young Citrus Fruits Cultivated in China.

Fruits of six varieties of young citrus cultivated in China were collected for phytochemical composition analysis and antioxidant activity determination. The phenolic acids, synephrine, flavone, and flavanone were analyzed using HPLC, and the total phenolic content and antioxidant capacity were determined by Folin-Ciocalteu, Ferric ion reducing antioxidant power (FRAP), 2,2- 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) analysis. The results indicated that Ougan variety had the highest total phenolic content (125.18 GAE mg/g DW), followed by the Huyou variety (107.33 mg/g DW), while Wanshuwenzhoumigan variety had the lowest (35.91 mg/g DW). Ferulic acid was the most dominant soluble phenolic acid in the selected young citrus, followed by p-coumaric acid and p-hydroxybenzoic acid, whereas nobiletin and tangeretin were the most abundant flavones in the Ponkan, Ougan, and Wanshuwenzhoumigan varieties. Antioxidant capacity that measured by ABTS, FRAP, and DPPH showed similar trends and was positively correlated with the total phenolic and total flavonoid contents (p < 0.05). Considering the high content of phenolics in the young fruits of Ougan and Huyou variety, those two varieties might be potential resources for extracting phytochemicals for health promotion.

Application of Curcumin Emulsion Carrier from Ultrasonic-Assisted Prepared Octenyl Succinic Anhydride Rice Starch.

The emulsification of ultrasonic-assisted prepared octenyl succinic anhydride (OSA) rice starch on curcumin was investigated in the present study. The results indicated that the encapsulation efficiency of curcumin in emulsions stabilized by OSA-ultrasonic treatment rice starch was improved, from 81.65 ± 0.14% to 89.03 ± 0.09%. During the in vitro oral digestion, the particle size and Zeta potential of the curcumin emulsion did not change significantly (p > 0.05). During the in vitro digestive stage of the stomach and small intestine, the particle size of the curcumin emulsion continued to increase, and the absolute potential continued to decrease. Our work showed that OSA-pre-treatment ultrasonic rice starch could improve curcumin bioavailability by increasing the encapsulation efficiency with stronger stability to avoid the attack of enzymes and high intensity ion, providing a way to develop new emulsion-based delivery systems for bioactive lipophilic compounds using OSA starch.

Effect of Potato Pulp Pectic Polysaccharide on the Stability of Acidified Milk Drinks.

In order to broaden the application of potato pulp pectic polysaccharide (PPP) in stabilizing acidified milk drinks (AMDs) and investigate the stabilizing effect and physical properties of AMDs prepared with PPP, a comparative study was made among PPP, commercial high methoxyl pectin (HMP) and low methoxyl pectin (LMP). The zeta potential, rheology, particle size and serum separation of AMDs were evaluated after preparing with PPP, HMP and LMP, respectively. Results indicated that PPP led to lower serum separation than LMP (14.65% for AMDs prepared with 0.5% PPP compared to 25.05% for AMDs prepared with 0.5% LMP), but still higher than HMP (9.09% for AMDs prepared with 0.5% HMP). However, narrower particle size distribution and lower viscosity of AMDs was achieved by PPP than by LMP and HMP. PPP can electrostatically adsorb on the surface of casein and its abundant neutral sugar side chains would provide steric hindrance to prevent casein flocculation in AMDs. Our results might provide some new ideas for the application of PPP in improving the stability of AMDs.

Physicochemical and Digestion Properties of Potato Starch Were Modified by Complexing with Grape Seed Proanthocyanidins.

Dietary intake of potato starch could induce a dramatic increase in blood glucose and is positively associated with chronic metabolic diseases (type II diabetes, cardiovascular disease, etc.). Grape seed proanthocyanidins (GSP) are known to decrease starch digestion by inhibiting digestive enzymes or changing the physicochemical properties of starch. In the present study, GSP were complexed with potato starch to prepare polyphenol-starch complexes. The physiochemical properties and digestibility of complexes were investigated by in vitro digestion model, X-ray diffraction, differential scanning calorimetry, rapid visco analyzer, Fourier transform infrared spectroscopy as well as texture profile analysis. Results indicated that the peak viscosity, breakdown, trough, and setback of the complexes disappeared, replaced by a special continuous increase in paste viscosity. The complexes showed a lower final viscosity and higher thermal stability with the increasing binding amount of GSP. GSP decreased the hardness of the complexes' gel significantly. FT-IR indicated that GSP might interact with potato starch through noncovalent forces. Additionally, the complexes also showed a higher content of slowly digestible starch and resistant starch than that of the native starch. Thus, we inferred that the addition of GSP could modify the digestibility of potato starch and be an optional way to modify the starch with lower digestion.

The microstructure of starchy food modulates its digestibility.

Starch is the main carbohydrate in human nutrition and shows a range of desired food properties. It has been demonstrated that fast digestion of starchy food can induce many health issues (e.g., hyperglycaemia, diabetes, etc.); therefore, how to modulate its digestion is an interesting topic. Previous studies have revealed that the microstructure and digestibility of starchy food of different botanical origin or from multiple processes are quite different; modulating starch digestion by retaining or altering its microstructure may be effective. In the present review, the current knowledge of the relationship between microstructural changes to starchy food and its digestibility at molecular, cell and tissue, and food processing levels is summarized. New technologies focused on microstructure studies and ways to manipulate food microstructure to modulate starch digestibility are also reviewed. In particular, some insights focusing on the future study of microstructure and the digestibility of starchy food are also suggested.

Recovery of High Value-Added Nutrients from Fruit and Vegetable Industrial Wastewater.

The industrial processing water of fruit and vegetables has raised serious environmental concerns due to the presence of many important bioactive compounds being disposed in the wastewater. Bioactive compounds have great potential for the food industry to optimize their process and to recover these compounds in order to develop value-added products and to reduce environmental impacts. However, to achieve this goal, some challenges need to be addressed such as safety assurance, technology request, product regulations, cost effectiveness, and customer factors. Therefore, this review aims to summarize the recent advances of bioactive compounds recovery and the current challenges in wastewater from fruit and vegetable processing industry, including fruit and beverage, soybean by-products, starch and edible oil industry. Moreover, future direction for novel and green technology of bioactive compounds recovery are discussed, and a prospect of bioactive compounds reuse and sustainable development is proposed.

Polyphenol Extracts from Ziziphus jujuba Mill. "Junzao" Attenuates Ulcerative Colitis by Inhibiting the NLRP3 and MAPKs Signaling Pathways and Regulating Gut Microbiota Homeostasis in Mice.

SCOPE: Polyphenols are the major active substances in red jujube fruit, and their anti-inflammatory and antioxidant activities suggest their potential utility in the prevention of ulcerative colitis (UC). METHODS AND RESULTS: In this study, the effect of polyphenol extracts from red jujube (Ziziphus jujuba Mill. "Junzao") (PERJ) on the dextron sulfate sodium (DSS)-induced UC mice is investigated. The result shows that PERJ effectively improves clinical symptoms, including food and water intake, the disease activity insex (DAI) and spleen index, and routine blood levels, and alleviates the shortening of the colon, in mice with DSS-induced UC. Meanwhile, PERJ remarkably decreases the expression of proinflammatory factors. Moreover, PERJ repairs intestinal barrier damage by increasing the expression level of mucin 2 and mucin 3, and the result is also confirmed in the histological assessment. Besides, the expression levels of Nod-like receptor family pyrin domain-containing 3 (NLRP3) and mitogen-activated protein kinase cascade (MAPKs) signaling pathway-related proteins are inhibited by the PERJ administration. Finally, 16S rRNA sequencing analyses reveal that PERJ reverses intestinal microbiota dysbiosis by enhancing the abundance of Firmicutes and decreasing that of Proteobacteria and Bacteroidetes. CONCLUSION: PERJ probably inhibits the development of UC by suppressing the NLRP3 and MAPKs signaling pathways and regulating gut microbiota homeostasis, and can be considered as a potential resource for preventing UC.

Enhance the resistance of probiotics by microencapsulation and biofilm construction based on rhamnogalacturonan I rich pectin.

Microcapsules were always used as functional material carriers for targeted delivery and meanwhile offering protection. However, microcapsule wall materials with specific properties were required, which makes the choice of wall material a key factor. In our previous study, a highly branched rhamnogalacturonan I rich (RG-I-rich) pectin was extracted from citrus canning processing water, which showed good gelling properties and binding ability, indicating it could be a potential microcapsule wall material. In the present study, Lactiplantibacillus plantarum GDMCC 1.140 and Lactobacillus rhamnosus were encapsulated by RG-I-rich pectin with embedding efficiencies of about 65 %. The environmental tolerance effect was evaluated under four different environmental stresses. Positive protection results were obtained under all four conditions, especially under H2O2 stress, the survival rate of probiotics embedded in microcapsules was about double that of free probiotics. The storage test showed that the total plate count of L. rhamnosus encapsulated in RG-I-rich pectin microcapsules could still reach 6.38 Log (CFU/mL) at 25 °C for 45 days. Moreover, probiotics embedded in microcapsules with additional incubation to form a biofilm layer inside could further improve the probiotics' activities significantly in the above experiments. In conclusion, RG-I-rich pectin may be a good microcapsule wall material for probiotics protection.

Phenolic metabolites changes during baijiu fermentation through non-targeted metabonomic.

To investigate the changes of phenolic metabolite during different grains fermentation stages of Chinse Baijiu, the ultra-performance liquid chromatography-quadrupole time of-flight mass spectrometry (UHPLC-QTOF-MS) was applied to identify and analyze the different phenolic metabolites, combined with principal component analysis and partial least squares discriminant analysis. Results indicated that significant differences in phenolic metabolites during different fermentation stages were found. Among the 231 phenolic metabolites detected, 36, 31, 19, 23, 14, and 50 differential phenolic metabolites were screened between different groups using partial least squares discriminant analysis. Twelve metabolic pathways with high correlation of differential phenolic metabolites and 23 main participating differential metabolites were identified through KEGG metabolic pathway enrichment analysis. The present study preliminarily revealed the differences of phenolic metabolites at different fermentation stages, and providing a theoretical basis for the further improving of the taste and quality of Chinese Baijiu.

Changes in Polyphenols and Antioxidant Activity in Fermentation Substrate during Maotai-Flavored Liquor Processing.

To investigate the changes in phenols and antioxidant capacity in fermented grains during different stages of the fermentation process (Xiasha, Zaosha, and single-round stages) of Maotai-flavored liquor, the total phenolic contents of 61 samples, collected in different stages, were analyzed via the Folin-Ciocalteu method, and the phenolic compounds were then identified by high-performance liquid chromatography (HPLC). Subsequently, the antioxidant activities were determined using the DPPH free radical scavenging rate and ABTS and FRAP antioxidant capacities. The correlations among the total phenolic contents, individual phenolics, and three antioxidant activities of the samples were analyzed. The results show that the total phenolic contents of the fermented samples did not change significantly in the Xiasha and Zaosha stages but showed an upward trend in the single-round stage. A total of 12 phenol acids were identified in the fermented grains, including 5 phenolic acids (e.g., ferulic acid and caffeic acid), 4 flavonoids (e.g., luteolin and apigenin), and 3 proanthocyanidins (e.g., apigeninidin), for which the DPPH free radical scavenging rates and ABTS and FRAP antioxidant capacities of all of the fermented grain samples ranged from 78.91 ± 4.09 to 98.57 ± 1.52%, 3.23 ± 0.72 to 13.69 ± 1.40 mM Trolox, and 5.06 ± 0.36 to 14.10 ± 0.69 mM FeSO4, respectively. The total phenolic contents of the fermented grain samples were significantly and positively correlated with the ABTS and FRAP (p ≤ 0.05), while no significant correlations were found between total phenolic content and DPPH. In general, the total phenolic content, phenolic substances, and antioxidant capacity of the fermented grains exhibited changes during the fermentation process in liquor production, and the phenolic components contributed more to the antioxidant properties of the fermented grains. The present study provides a theoretical reference for analyzing the dynamic changes and antioxidant properties of functional phenolic components in fermented grains.

Effect of hawthorn polyphenol extracts on the physicochemical properties and digestibility of corn starch.

To investigate the effect of hawthorn polyphenols on the physicochemical properties and digestibility of corn starch, different proportions (1%, 2%, 3%, and 4% [w/w]) of hawthorn polyphenol extracts (HPEs) were mixed with corn starch, and their physicochemical properties and digestive properties were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Rapid Visco Analysis, differential scanning calorimetry, and in vitro/in vivo analysis. Results indicated that small V-type crystal starch tended to be formed in the samples, and the addition of HPEs reduced the viscosity, prolonged the gelatinization temperature of corn starch, and increased the proportion of slowly digestible starch and resistant starch of the corn starch, which accounted for 36.32% ± 1.05% and 33.32% ± 4.07%, respectively. Compared with the raw corn starch, the postprandial blood glucose of mice that were administered the hawthorn polyphenols decreased significantly: the blood glucose peak (30 min) decreased from 14.30 ± 1.52 to 11.77 ± 1.21 mmol/L. Our study might provide some basic theoretical support for the application of hawthorn polyphenols in healthy starchy food processing.

Development and characterization of pH responsive sodium alginate hydrogel containing metal-phenolic network for anthocyanin delivery.

Favorable hydrogels can be used as a material to deliver bioactive molecules and improve the stability of bioactive substances, while their safety needs to be improved. In this study, protocatechuic acid (PCA) and Fe3+ were rapidly self-assembled to form a metal-phenolic network under different pH conditions, and then sodium alginate (SA) was added to prepare the SA/PCA/Fe hydrogel without adding other chemical reagents. The structural characteristic of SA/PCA/Fe hydrogel was characterized by infrared spectroscopy, X-ray diffraction analysis and scanning electron microscopy. The results showed that the structures of SA/PCA/Fe hydrogels prepared at different pH values were significantly different. The texture analysis, water-holding measurement and rheological analysis indicated that the SA/PCA/Fe hydrogel showed higher gel strength, water holding capacity and storage modulus. Thermogravimetric analysis illuminated that the SA/PCA/Fe hydrogel enhanced the thermal stability of free anthocyanins through encapsulating anthocyanins. Moreover, in vitro simulated digestion experiment revealed that SA/PCA/Fe hydrogel could control the release of anthocyanins in the simulated gastrointestinal tract. To sum up, this present study might provide a safer and feasible way for the delivery of bioactive substances.

Effect of annealing treatment on the physicochemical properties and enzymatic hydrolysis of different types of starch.

Annealing treatment on the physicochemical properties and hydrolysis of maize, potato and pea starch were investigated in present study. Results indicated that annealing treatment did not change the morphology of the starch. However, the relative crystallinity of maize and potato starch showed a peak trend as the annealing time extended, while pea starch showed a lower relative crystallinity. Besides, all the annealed starch showed a decrease in peak viscosity and an increase in pasting time. Little difference in the rapidly digestive starch (RDS) and resistant starch (RS) contents of annealed maize starch and pea starch were observed after annealing, while annealed potato starch (72 h) showed an increased RS content (23.37 ± 5.36 %) and a decreased RDS content (52.60 ± 6.14 %), respectively. The obtained results may provide a better understanding of the physicochemical properties and enzymatic hydrolysis of annealed starch with different semi crystalline type.

Regulating the physicochemical, structural characteristics and digestibility of potato starch by complexing with different phenolic acids.

The effects of ferulic acid (FA), protocatechuic acid (PA), and gallic acid (GA) on the physicochemical characteristics, structural properties, and in vitro digestion of gelatinized potato starch (PS) were investigated. Rapid viscosity analysis revealed that the gelatinized viscosity parameters of PS decreased after complexing with different phenolic acids. Dynamic rheology results showed that phenolic acids could reduce the values of G' and G″ of PS-phenolic acid complexes, demonstrating that the addition of phenolic acids weakened the viscoelasticity of starch gel. Fourier-transform infrared spectra and X-ray diffraction results elucidated that phenolic acids primarily reduced the degree of short-range ordered structure of starch through non-covalent interactions. The decrease in thermal stability and the more porous microstructure of the complexes confirmed that phenolic acids could interfere with the gel structure of the starch. The addition of different phenolic acids decreased the rapidly digestible starch (RDS) content and increased the resistant starch (RS) content, with GA exhibiting the best inhibitory capacity on starch in vitro digestibility, which might be associated with the number of hydroxy groups in phenolic acids. These results revealed that phenolic acids could affect the physicochemical characteristics of PS and regulate its digestion and might be a potential choice for producing slow digestibility starch foods.

Pectin from Citrus unshiu Marc. Alleviates Glucose and Lipid Metabolism by Regulating the Gut Microbiota and Metabolites.

The effects of pectin from Citrus unshiu Marc. on glycolipid metabolism, the morphologies of the pancreas and epididymal fat, the gut microbiota, and the metabolites of short-chain fatty acids (SCFAs) in db/db mice were investigated in this study. The results indicated that pectin reduced the levels of fasting blood glucose, glycated serum protein, triglycerides, total cholesterol, and low-density lipoprotein cholesterol while increasing the levels of high-density lipoprotein cholesterol. Meanwhile, pectin could improve the morphology of islet cells and inhibit the hypertrophy of adipocytes. Additionally, pectin not only regulated the intestinal flora dysbiosis in db/db mice, as shown by the increasing proportion of Firmicutes/Bacteroidetes and the relative abundance of Ligilactobacillus, Lactobacillus, and Limosilactobacillus, but also remedied the metabolic disorder of SCFAs in db/db mice. These results suggest that pectin could promote glucose and lipid metabolism by regulating the intestinal flora with changes in SCFA profile. This study proves that pectin might serve as a new prebiotic agent to prevent the disorder of glycolipid metabolism.

Physicochemical properties and in vitro digestibility of proso millet starch modified by heat-moisture treatment and annealing processing.

Heat-moisture treatment (HMT) and annealing (ANN) were applied to modify the proso millet starch, and then the physicochemical properties as well as the in vitro digestion of the modified starch were investigated systematically. Results indicated that HMT and ANN did not change the typical A-type crystallinity. However, both processes cause cracks and dents on the surface of the granule. The gelatinization temperature increased while peak viscosity value, relative crystallinity and gelatinization enthalpy of proso millet starch decreased significantly after HTM and ANN. Meanwhile, a remarkable increase of the slowly digestible starch(SDS) and resistant starch(RS) content was noticed after HTM and ANN modification (the highest content of SDS and RS after HTM and ANN were 9.52 ± 0.82 %, 12.03 ± 1.36 % and 12.15 ± 0.89 %, 8.75 ± 1.63 %, respectively). Those results indicated that the ANN and HMT processes could modify the physicochemical properties and in vitro digestion of proso millet starch efficiently and showed potential application to produce healthy starch food with lower digestion.

Photo-crosslinking modified sodium alginate hydrogel for targeting delivery potential by NO response.

In recent years, the incidence of inflammatory bowel disease has gradually increased. Traditional drugs can reduce inflammation, but cannot be targeting released and often require the coordination with delivery systems. However, a good targeting performance delivery system is still scarce currently. Inflammation can trigger oxidative stress, producing large amounts of oxides such as nitric oxide (NO). Based on this, the present experiment innovatively designed a hydrogel delivery system with NO response that could be inflammation targeting. The hydrogel is composed of sodium alginate modified with glycerol methacrylate, crosslinked with NO response agent by photo-crosslinking method, which have low swelling (37 %) and good mechanical properties with a stable structure even at 55 °C. The results of in vitro digestion also indicated that the hydrogel had a certain tolerance to gastrointestinal digestion. And in the NO environment, it was interestingly found that the structure and mechanical properties of the hydrogels changed significantly. Moreover, hydrogels have good biocompatibility, which ensures their safe use in vivo. In conclusion, this NO-responsive-based delivery system is feasible and provides a new approach for drugs and active factors targeting delivery in the future.