摘要:
The addition of oat at varying percentages (26%, 32%, 38%, 44% and 50%) was used to evaluate the structural, microstructural, and physicochemical changes in instant-extruded rice (IER). A mixture of broken rice and oat flour was extruded in a twin-screw extruder. It was found that when adding 44% oats, the gelatinization degree of the mixed powder was the lowest (89.086 ± 1.966%). The dietary fiber content increased correspondingly with the increase in oat addition. Analyses of texture properties revealed that the hardness, adhesive, and resilience values increased and then decreased with oat addition. Compared with other common instant rice (IR), the advantages of IER were evaluated in terms of microstructure, digestive performance, and flavor. IER with 44% oat addition obtained in this study had higher hardness, adhesiveness, rehydration time, and sensory score, and the content of resistant starch (RS) reached 6.06%. The electronic nose and electronic tongue analyses could distinguish the flavor of different IR efficiently. This study showed the feasibility of preparing fiber-enriched IER. The results demonstrated the potential for the development and utilization of broken rice, providing a reference for the development of IER.
通讯机构:
[Quan, W ] H;Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410128, Peoples R China.;Jiangnan Univ, State Key Lab Food Sci & Technol, Wuxi 214122, Peoples R China.
关键词:
citrus peel;polymethoxylated flavonoids;heterocyclic amines;advanced glycation end products;pork meat patties
摘要:
In the present study, citrus peels were extracted using various conventional and deep eutectic solvents (DESs). Compared to other citrus peel extracts, the DES extract based on choline chloride showed notably higher total phenolic and flavonoid content levels, along with superior antioxidant activity, among these extracts. Consequently, this study aimed to further investigate the inhibitory effects of the choline chloride based DES extract on the production of both free and bound heterocyclic amines (HAs) and advanced glycation end products (AGEs) in roast pork meat patties. The results indicated that the addition of choline chloride-based DES extracts, particularly the choline chloride-carbamide based DES extract, can effectively reduce the oxidation of lipids and proteins by quenching free radicals. This approach proves to be the most efficient in reducing the formation of both HAs and AGEs, leading to a significant reduction of 19.1-68.3% and 11.5-66.5% in free and protein-bound HAs, respectively. Moreover, the levels of free and protein-bound AGEs were reduced by 50.8-50.8% and 30.5-39.8%, respectively, compared to the control group. Furthermore, the major phenolics of citrus peel extract identified by UHPLC-MS were polymethoxylated flavonoids (PMFs) including hesperidin, isosinensetin, sinensetin, tetramethoxyflavone, tangeretin, and hexamethoxyflavone, which inferring that these compounds may be the main active ingredients responsible for the antioxidant activity and inhibition effects on the formation of HAs and AGEs. Further research is needed to explore the inhibitory effects and mechanisms of PMFs with different chemical structures on the formation of HAs and AGEs.
摘要:
This paper reports the preparation and characterization of gelatin-cassava starch microspheres using the water-in-water emulsion technique. The effects of different weight ratios (10: 0, 9: 1, 8: 2, 7: 3, 6: 4, 5: 5) of starch to gelatin on the morphology, structure, thermal properties, and stability of microspheres were investigated. The morphology results showed that most microspheres had spherical shapes and smooth surfaces. When the weight ratio of starch to gelatin was 5: 5, the prepared microspheres formed a stable yolk-shell structure. The swelling capacity of the microspheres increased with the proportion of gelatin, up to 682.3%. The gelatin and starch in the microspheres were compatible but not miscible. Compared with the native starch, the crystalline structure of microspheres changed from A-type to a mixture of B-type and V-type, and the relative crystallinity decreased. Differential scanning calorimetry results showed that the melting of microspheres involved both gelatin dissolution and starch gelatinization. Due to the formation of composite microspheres, the starch content decreased, and the release of reducing sugars from the microspheres upon hydrolysis was reduced. The gelatin-cassava starch microspheres are simple to prepare, biocompatible, and can be used as a potential material for microencapsulation.
关键词:
Aggregation of gold nanoparticles;Aptamer-initiator stand;Dual-modality;Functional DNA;Hybridization chain reaction
摘要:
Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins, which is frequently detected in agricultural products. Herein, a novel functional DNA -linked immunosorbent assay (DLISA) with dual-modality based on hybrid chain reaction (HCR) has been successfully developed for ultrasensitive detection of AFB1. The strategy relies on AFB1 immune-bridged occurrence of HCR and the salt-induced aggregation of gold nanoparticles (AuNPs). An aptamer-initiator stand (Apt-Ini stand) is designed for the AFB1 recognition and the activation of HCR, which can recognize the matched hairpins and cause the crossing-opening of H1 and H2, producing a long double-stranded DNA polymer. The addition of SYBR Green I achieves the fluorescent signal output. Remaining less DNA hairpins were added and stuck on the surface of AuNPs, which were insufficient to protect the AuNPs, resulting in the salt-induced aggregation with the color change from red to blue. The dual-modality provides limits of detections of 1.333×10(-14) g/mL and 2.471×10(-15) g/mL, respectively. This DLISA with dual-modality provides not only a colorimetry that can meet the needs of on-the-spot preliminary inspection, but also a fluorescence assay that can acquire the precise results.
通讯机构:
[Liu, XD ; Zhang, Y ] H;Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410128, Peoples R China.;Hunan Acad Forestry, State Key Lab Utilizat Woody Oil Resource, Changsha 410004, Peoples R China.
关键词:
Camellia oleifera shell;Acidic deep eutectic solvents;Microwave-assisted;Lignin;Lignin nanoparticles
摘要:
Camellia oleifera shell (COS) is a waste biomass resource and abundant in lignin. Effective fractionation and valorization of lignin is of great significance. In this work, choline chloride (ChCl) and allyl trimethylammonium chloride (ATMAC) as hydrogen bond acceptors, and lactic acid (LA), acetic acid (AA) and oxalic acid (OA) as hydrogen bond donors were used to prepare six different acidic deep eutectic solvents (DES). The lignin was fractionated from COS by microwave -assisted method using acidic deep eutectic solvents, and lignin nanoparticles (LNPs) were further fabricated by self -assembly strategy. The structural characteristics of lignin and LNPs were analyzed and compared. The results demonstrated that ATMAC-LA pretreatment exhibited the highest delignification of 81.41% and cellulose retention of 95.1%. The molecular weight of lignin extracted from ChClbased DES was lower than those obtained by ATMAC-based DES when using identical hydrogen bond donors. The smallest average particle size (203.07 nm) of LNPs was obtained by ATMAC-AA pretreatment. In addition, ATMAC-LA exhibited the highest interaction energy of 56.1 kcal/mol and stronger electrostatic potential (- 46.72-54.58 kcal/mol), which elucidated its high delignification efficiency. ATMAC-LA DES exhibited high selectivity for lignin dissolution, and LNPs with smaller particle size and excellent stability could be fabricated. This work provides an efficient method to fractionate lignin from COS at 150 celcius for 15 min, and contributing to extend the opportunities of lignin valorization into bio-based materials.
摘要:
Ganpu vine tea is a new type of health care citrus fruit tea made from citrus shell, Pu-er tea, and vine tea baked as raw materials. In this study, the in vitro uric acid synthase inhibition system and hyperuric acid cell model were constructed to appraise the uric acid lowering efficacy of Ganpu vine tea, traditional Ganpu tea, and vine tea. Results showed that in the uric acid synthase inhibition system, the aqueous extract can inhibite the puric metabolically related enzymes, such as adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and xanthine oxidase (XOD). The ability of the aqueous extract to inhibit the above enzyme was as follows: vine tea > Ganpu vine tea > Ganpu tea; all teas had a strong effect on XOD inhibition. The hyperuric acid cell model test showed that the aqueous extract inhibited uric acid production through accumulating inosine and hypoxanthine and hindering xanthine synthesis. The uric acid reductive ability was as follows: Vine tea > Ganpu vine tea > Ganpu tea. The inhibition of enzymes related to uric acid synthesis and the inhibition of uric acid production were significantly enhanced through adding vine tea to Ganpu tea. It also shows that flavonoids are the main factor driving this ability because they are the main active ingredients in these botanical drinks.
摘要:
The effect of alkaline microcrystalline cellulose (AMC) deacidification and alkali refining on the physicochemical properties, fatty acid profile, active phytochemicals, antioxidant capacity, and volatile flavor components of crude camellia oil (CO) were investigated comparatively. The results showed that the acid value of AMC deacidification camellia oil (ADO) was effectively decreased from 1.50 & PLUSMN; 0.00 mg KOH/g to 0.30 & PLUSMN; 0.01 mg KOH/g. AMC deacidification more effectively retained 60.22% of the polyphenols (12.34 & PLUSMN; 0.38 mg GAE/100g), 74.60% of & alpha;-tocopherol (2.82 & PLUSMN; 0.00 mg/kg) and 93.25% of & beta;-Sitosterol (5.30 & PLUSMN; 0.05 mg/100g) in camellia oil compared to alkali refining and showed a stronger overall antioxidant capacity of the oil (P < 0.05). In addition, the volatile flavors of camellia oil were dominated by acids, aldehydes, and alcohols, and AMC deacidification better preserved the acidic flavors than alkali refining. Principal component analysis (PCA) revealed that ADO and CO were positively correlated with PC1 due to the highly in relation to the higher content of 9C, 11 TRConjugated linoleic acid and the stronger antioxidant capacity. Overall, AMC deacidification was moderate reaction conditions and zero wastewater production, making it a potentially effective alternative method in camellia oil deacidification.
摘要:
Research of lactic acid bacteria and its metabolites on biological preservatives becomes a hot topic. Lactobacillus plantarum O(2), with good inhibition on Phytophthora capsici (P. capsici), was isolated from the pickle. In this study, the effects of L. plantarum O(2) fermentation supernatant (FS) on pepper postharvest preservation and its induced resistance to P. capsici were studied. Results showed that weight loss rate, rot index, respiration rate, relative electrical conductivity, loss of chlorophyll content and V(C) of pepper in FS treatment group were decreased by 18 %, 64 %, 15 %, 26 %, 33 % and 20 % compared with blank control (BC) after 20d storage. L* and b*-value of pepper in FS group were lower than those in the BC group. In addition, the damage-induced resistance test found that the infection rate in the FS group was reduced by 39 %, compared with CK2 after 12d storage. Moreover, phenylalanine ammonia-lyase activity, peroxidase activity, polyphenol oxidase activity, proline content, total phenol content and flavonoid content increased by 14 %, 9 %, 30 %, 8 %, 8 % and 9 %, respectively, while malondialdehyde content decreased by 13 %. These results indicated that FS treatment showed good fresh-keeping effects on postharvest pepper. It could enhance the tolerance of pepper under stress by improving defensive enzyme activities, slowing down the damage caused by P. capsici, and inducing pepper resistance to P. capsici. Therefore, FS can be used as a microbial source bio-preservative for postharvest pepper.
通讯机构:
[Tiean Zhou; Yanyang Wu] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Provincial Engineering Technology Research Center for Cell Mechanics and Function Analysis, Changsha 410128, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China
通讯机构:
[Zongjun Li] C;College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
摘要:
Protein-bound N(ε)-(carboxymethyl)lysine (CML), an advanced glycation end product within meat products, poses a potential health risk to humans. The objective of this study was to explore the impact of various edible oils on the formation of protein-bound CML in roasted pork patties. Eleven commercially edible oils including lard oil, corn oil, palm oil, olive oil, flaxseed oil, blended oil, camellia oil, walnut oil, soybean oil, peanut oil, and colza oil were added to pork tenderloin mince, respectively, at a proportion of 4% to prepare raw pork patties. The protein-bound CML contents in the pork patties were determined by HPLC-MS/MS before and after roasting at 200°C for 20min. The results indicated that walnut oil, flaxseed oil, colza oil, olive oil, lard oil, corn oil, blended oil, and palm oil significantly reduced the accumulation of protein-bound CML in pork patties, of which the inhibition rate was in the 24.43%-37.96% range. Moreover, the addition of edible oil contributed to a marginal reduction in the loss of lysine. Meanwhile, glyoxal contents in pork patties were reduced by 16.72%-43.21% after roasting. Other than blend oil, all the other edible oils restrained protein oxidation in pork patties to varying degrees (between 20.16% and 61.26%). In addition, camellia oil, walnut oil, and flaxseed oil increased TBARS values of pork patties by 2.2-8.6 times when compared to the CON group. After analyzing the fatty acid compositions of eleven edible oils, five main fatty acids (palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid) were selected to establish Myofibrillar protein-Glucose-fatty acids systems to simulate the roasting process. The results showed that palmitic acid, oleic acid, linoleic acid, and linolenic acid obviously mitigated the formation of myofibrillar protein-bound CML, exhibiting suppression rates ranging from 10.38% to 40.32%. In conclusion, the addition of specific edible oil may curb protein-bound CML production in roasted pork patty by restraining protein or lipid oxidation, reducing lysine loss, and suppressing glyoxal production, which may be attributed to the fatty acid compositions of edible oils. This finding provides valuable guidance for the selection of healthy roasting oils in the thermal processing of meat products.
通讯机构:
[Zongjun Li] C;College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词:
Small berry pomace;Nutrition;Phytochemical;Antioxidant activity;Metabolomics
摘要:
Small berry pomaces (SBPs) are poorly utilized as an inexpensive source of bioactive compounds. This study investigated the impact of compounding treatment on nutritional and antioxidant characteristics of combined SBPs, in comparison with single SBP. The results showed that the amounts of protein, minerals, dietary fiber (DF) and anthocyanidins were significantly (p < 0.05) higher in combined SBPs than in combined fruits. Moreover, the combined SBPs were characterized by an elevated abundance of minerals and anthocyanidins (6 kinds, and 5 kinds, respectively), substantiating the effectiveness of compounding treatment on SBP nutrition. A total of 776 secondary phytochemicals were detected in combined SBPs by a widely targeted metabolomics approach. Each SBP contained approximately 100 kinds of unique natural antioxidants. Furthermore, the combined SBPs group had the highest antioxidant activity compared with single SBP. Meanwhile, the antioxidant activities determined in combined SBPs were higher than arithmetic mean value of single SBP. The synergism and interaction of active components in different sources of SBPs play vital role in the high antioxidant capacity of combined SBPs. All the results provide reference for the comprehensive development and utilization of fruit residues. The SBPs should be highly prized for their substantial amount of nutritional and bioactive constituents, including protein, DF, essential minerals and secondary metabolites. These secondary metabolites are positively associated with antioxidant benefits. The present study summarizes the knowledge about bioactive compounds and antioxidant activities of combined SBPs group and discusses the relevant mechanisms. A conclusion can be educed that combined process is an effective way to improve properties of the pomaces.
通讯机构:
[Xingbo Shi; Xingbo Shi Xingbo Shi Xingbo Shi] L;Laboratory of Micro & Nano Biosensing Technology in Food Safety, Hunan Provincial Key Laboratory of Food Science and Biotechnology, College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128 China
关键词:
biosensing;catalyses;DNA;imaging;prussian blue nanoflowers
摘要:
DNA is use to precisely control the morphology of prussian blue nanoparticles (PBNPs) via electrostatic interaction‐mediated self‐assembly of inorganic ions and protonated DNA for the first time. The flower‐like PBNPs (PB nanoflowers) mediated by 30‐mer Oligo‐C exhibit excellent photothermal properties, mimetic peroxidase activity, biorecognition ability, photo‐fenton catalytic performance and light scattering, and is expected to be widely used in biosensing, catalysis and imaging. Abstract While shapes and surface properties of nanomaterials are known to play important roles in defining their properties, it remains challenging to fine‐tune the morphologies systematically and predictably. Considering the extraordinary performance, prussian blue nanoparticles (PBNPs) are selected as the proof‐of‐concept nanomaterials. Herein, a DNA‐dependence approach to fine‐control the morphology of PBNPs via electrostatic interaction‐mediated self‐assembly of inorganic ions and protonated DNA is developed. The regulation of different DNA on the morphology of PBNPs is systematically investigated. 30‐mer Oligo‐C or ‐T (C30/T30) mediates formation of flower‐like PBNPs (PB nanoflowers), whereas cubic structure with different sizes is observed in the presence of 10‐mer oligo‐G or 30‐mer Oligo‐A (G10/A30). Detailed mechanism studies indicate that the protonation of nucleobases is the key factor for the morphological evolution. C30‐dependent PB nanoflowers are superior to PB nanocubes in photothermal properties, peroxidase mimetic activity, photo‐Fenton catalytic performance, and light scattering property, which present 1.2‐, 3.78‐, 1.58‐, 1.93‐fold improvement, respectively. Furthermore, PB nanoflowers mediated by the diblock DNA (sDNA; comprising C30 and complementary strands of the target DNA) unexpectedly acquire biorecognition capabilities. This work opens a new avenue for the systematic and predictable synthesis of PB nanoflowers, which broadens the repertoire of PBNPs for catalysis, biosensing, and imaging.
摘要:
L. monocytogenes (L. m) is one of the most common causes of foodborne diseases. To enable timely monitoring of L. m contamination, a highly efficient and sensitive electrochemical biosensor was developed for the precise determination of L.m. The biosensor was prepared by sequentially modifying glassy carbon electrode (GCE) with silicon methylene blue (Si@MB), gold nanoparticles (AuNPs) and aptamer (Apt). Differential pulse voltammetry (DPV) was used to quantify L.m. This biosensor could be finished in 1.5 h, which significantly reduced the detection time. The resulting electrochemical biosensor achieved good linear (102-107 CFU/mL) and excellent detection limit of 2.6 CFU/mL. Moreover, the novel strategy has been successfully applied to actual samples, with the recoveries ranging from 84.7% to116.0% in lettuce and from 80.0% to 110% in fresh-cut fruit. This biosensor shows great potential application in monitoring bacterial food contamination and infectious diseases.
摘要:
An accurate and nondestructive detection method of hidden mold infection in citrus was established based on portable near infrared diffuse reflectance spectroscopy (NIRDRS) and chemometric methods. Penetrability of NIRDRS light on the peel of Chunjian hybrid citrus was studied. The results show that NIRDRS light can penetrate the peel to a certain extent, while the penetrability of short-wave near infrared (SWNIR) was better than that of long-wave near infrared (LWNIR). The identification models of hidden mold infection were established with five pattern recognition methods combined with different wavelength bands. The results show that the identification models of LWNIR were much better than those of SWNIR. 100% identification accuracies of LWNIR were ob-tained with soft independent pattern classification (SIMCA), support vector machine (SVM), partial least squares discriminant analysis (PLS-DA) and the optimized pretreatment methods. In addition, the developed models were further validated by the external validation set collected one month later.