Investigation of interactions between Jiuzao glutelin with resveratrol, quercetin, curcumin, and azelaic and potential improvement on physicochemical properties and antioxidant activities.

The interactions among small molecular functional components (FCTs) within a food matrix have become a focal point for enhancing their stability and bioactivities. Jiuzao glutelin (JG) is a mixed plant protein within Jiuzao (a protein-rich baijiu distillation by-product). This study aimed to explore the interactions between JG and selected FCTs, including resveratrol (RES), quercetin (QUE), curcumin (CUR), and azelaic acid (AZA), and the consequential impact on stability and antioxidant activity of the complexes. The findings conclusively demonstrated that the interactions between JG and the FCTs significantly enhanced the storage stability of the complexes. Moreover, the antioxidant activity of the complexes exhibited improvement compared to their individual counterparts. This study underscores the notion that JG and FCTs mutually reinforce, exerting positive effects on stability and antioxidant activity. This symbiotic relationship can be strategically employed to augment the quality of proteins and enhance the functional properties of bioactive components through these interactions.

High-throughput visualization mutation screening technology to enhance the specificity of CadR based whole-cell cadmium biosensor.

As a heavy metal pollutant, Cd2+ often enters the human body through the food chain causing great harm to human health. Whole-cell biosensor is an emerging technology for rapid on-site detection of heavy metals with the advantages of inexpensive, fast to mass-produce, and strong in anti-interference resistance, but suffering from insatisfactory specificity. In this study, a strategy of Adjacent Site Saturation Mutation (ASSM) was designed to improve the specificity of transcription factor CadR, which acted as the recognition element and determined the specificity of whole cell Cd2+ biosensors. A specific saturated library was constructed using the strategy of adjacent mutation. After two rounds of high-throughput visual screening, a whole-cell biosensor with good response to Cd2+, and with significant weakened Hg2+ interference was obtained. The optimized whole-cell biosensor showed a linear dynamic concentration range from 500 nM to 100 µM, a detection limit of 0.079 µM, and has satisfactory specificity and anti-interference. The ASSM strategy proposed in this study can provide a new method for the application of synthetic biology in food safety detection, indicating the importance of whole-cell biosensors for the detection of heavy metals.

Characteristics of saltiness-enhancing peptides derived from yeast proteins and elucidation of their mechanism of action by molecular docking.

This study aimed to identify saltiness-enhancing peptides from yeast protein and elucidate their mechanisms by molecular docking. Yeast protein hydrolysates with optimal saltiness-enhancing effects were prepared under conditions determined using an orthogonal test. Ten saltiness-enhancing peptide candidates were screened using an integrated virtual screening strategy. Sensory evaluation demonstrated that these peptides exhibited diverse taste characteristics (detection thresholds: 0.13-0.50 mmol/L). Peptides NKF, LGLR, WDL, NMKF, FDSL and FDGK synergistically or additively enhanced the saltiness of a 0.30% NaCl solution. Molecular docking revealed that these peptides predominantly interacted with TMC4 by hydrogen bonding, with hydrophilic amino acids from both peptides and TMC4 playing a pivotal role in their binding. Furthermore, Leu217, Gln377, Glu378, Pro474 and Cys475 were postulated as the key binding sites of TMC4. These findings establish a robust theoretical foundation for salt reduction strategies in food and provide novel insights into the potential applications of yeast proteins.

Photostimulus-Responsive Peptide Dot-Centered Covalent Organic Polymers: Effective Pesticide Sensing via Enhancing Accessibility.

Pesticide detection and monitoring are necessary for human health as the overapplication has serious consequences for environmental pollution. Herein, a proper modulation strategy was implemented to construct the photostimulus-responsive peptide-dot-centered covalent organic polymer (P-PCOP) nanoarchitecture for selective sensing of pesticides. The as-constructed P-PCOP was prepared at room temperature by using amino-containing peptide dots as a building block instead of common organic molecules, and the merits of P-PCOP enable it to reduce the steric hindrance of recognition, enhance the interfacial contact of the target, and facilitate the accessibility of sites, which promises to improve the sensitivity. The P-PCOF exhibited a low detection limit of 0.38 µg L-1 to cartap over the range of 1-80 µg L-1 (R2 = 0.9845), and the recoveries percentage in real samples was estimated to be 93.39-105.82%. More importantly, the DFT calculation confirmed the selective recognition ability of P-PCOP on chemical pesticides. In conjunction with a smartphone-integrated portable reading device, on-site chemical sensing is achieved. The proper modulation strategy of fixing a functional guest on the COP system contributes to the advanced structure-chemical properties that are conducive to their applications in chemical sensing.

Study on the saltiness-enhancing mechanism of chicken-derived umami peptides by sensory evaluation and molecular docking to transmembrane channel-like protein 4 (TMC4).

The previously obtained chicken-derived umami peptides in the laboratory were evaluated for their saltiness-enhancing effect by sensory evaluation and S-curve, and the results revealed that peptides TPPKID, PKESEKPN, TEDWGR, LPLQDAH, NEFGYSNR, and LPLQD had significant saltiness-enhancing effects. In the binary solution system with salt, the ratio of the experimental detection threshold (129.17 mg/L) to the theoretical detection threshold (274.43 mg/L) of NEFGYSNR was 0.47, which had a synergistic saltiness-enhancing effect with salt. The model of transmembrane channel-like protein 4 (TMC4) channel protein was constructed by homology modeling, which had a 10-fold transmembrane structure and was well evaluated. Molecular docking and frontier molecular orbitals showed that the main active sites of TMC4 were Lys 471, Met 379, Cys 475, Gln 377, and Pro 380, and the main active sites of NEFGYSNR were Tyr, Ser and Asn. This study may provide a theoretical reference for low-sodium diets.

Advances of nanoparticle derived from food in the control of α-dicarbonyl compounds-A review.

α-Dicarbonyl compounds (α-DCs) are predominantly generated through the thermal processing of carbohydrate and protein-rich food. They are pivotal precursors to hazard formation, such as advanced glycation end products (AGEs), acrylamide, and furan. Their accumulation within the body will be genotoxicity and neurotoxicity. Recently, significant advancements have been made in nanotechnology, leading to the widespread utilization of nanomaterials as functional components in addressing the detrimental impact of α-DCs. This review focuses on the control of α-DCs through the utilization of nanoparticle-based functional factors, which were prepared by using edible components as resources. Four emerging nanoparticles are introduced including phenolic compounds-derived nanoparticle, plant-derived nanoparticle, active peptides-derived nanoparticle, and functional minerals-derived nanoparticle. The general control mechanisms as well as the recent evidence pertaining to the aforementioned aspects were also discussed, hoping to valuable helpful references for the development of innovative α-DCs scavengers and identifying the further scope of research.

Characterization and sweetness-enhancing effect of peptides from yeast extract based on sensory evaluation and molecular docking approaches.

Yeast extract (YE) is derived from the soluble component in yeast cells, which is rich in peptides and has been used as a sweet-enhancing agent. It has the potential to be utilized to produce natural sweet-flavored peptides or sweet-enhancing peptides. To study the synergistic effect and mechanism of sweetness-enhancing peptides derived from YE, ultrafiltration fraction with molecular weight less than 1 kDa was screened according to sensory analysis, which showed a synergistic sweetening effect in stevioside and mogroside solution. Twenty potential taste peptides were identified from the screened fractions, among which EV, AM, AVDNIPVGPN and VDNIPVGPN showed sweetness-enhancing effects on both stevioside and mogroside. The sweetener-receptor-peptide complex was constructed to investigate the interaction of stevioside and mogroside to taste receptor type 1 member 2 accompanied by these peptides. The results of the molecular docking indicated that new hydrophobic interactions (Leu 279, Pro 308, Val 309, etc.) and hydrogen bonds (Ser 40, Ala 43, Asp 278, etc.) were formed between sweeteners and active sites in the venus flytrap domain. In conclusion, the presence of sweetness-enhancing peptides from YE improved the binding stability of sweeteners and receptors by increasing the binding interaction, especially the hydrophobic interactions, which contribute to the synergistic effect of sweetness-enhancing peptides.

Effects of cooking methods on aroma formation in pork: A comprehensive review.

Pork is widely consumed and appreciated by consumers across the world, and there are various methods of cooking pork. This study aimed to summarize the effects of different heat transfer media on pork flavor and the sources of flavor compounds. The cooking methods are classified based on the heat transfer media used, which include water and steam (e.g. steaming, boiling, and stewing), heat source or hot air (e.g. baking and smoking), oil (e.g. pan-frying, stir-frying, and deep frying), and other cooking technologies. The objective is to provide a reference for researchers studying pork cooking methods and flavor components.

A colorimetric fluorescent probe for the detection of carboxylesterase and carbamate pesticides.

A colorimetric fluorescent probe (BTCNA) was developed for the determination of carboxylesterase and carbamate pesticides. The probe used naphthalene-benzothiazole as the fluorescent group and naphthyl acetate as the recognition group. The recognition mechanism of BTCNA for carboxylesterase was based on the enzymatic hydrolysis of naphthyl acetate by carboxylesterase (CES). The test paper of the BTCNA gradually changed from light blue to bright yellow with the increase of CES activity. The probe solution gradually changed from light blue to earth-yellow as the carbaryl concentration increased. There was a linear functional relationship between the R*G (red, green) value of the photo and the CES activity. And a linear functional relationship between the carbaryl concentration and the R*G value of the photo was found. Additionally, BTCNA was successfully used to detect the concentration of carbaryl in actual samples. BTCNA is a rapid detection tool for CES activity and carbamate pesticides using a smartphone.

A dual-function fluorescent probe for the detection of pH values and formaldehyde.

A dual-function fluorescent probe (Probe 1) was developed in this work for the separate detection of pH value and formaldehyde (HCHO). Probe 1 could recognize HCHO and the pH value from the amino group. The colour of the probe solution was changed from grey blue to light blue with the increase in the pH value, and luminous intensity became larger with the increase in formaldehyde concentration. The curve function relationship between fluorescence intensity and the pH value was also determined. A smartphone containing a colour detector for imaging was used to record the values of the three primary colours (R value, G value, and B value) for the probe solution in formaldehyde. Importantly, there was a linear functional relationship between the B*R/G value with HCHO concentration. Therefore, the probe could be used as a rapid tool for the detection of formaldehyde. More importantly, Probe 1 was successfully used to detect formaldehyde in an actual distilled liquor sample.

Isolation and Characterization of Yeast with Benzenemethanethiol Synthesis Ability Isolated from Baijiu Daqu.

Baijiu, a prevalent alcoholic beverage, boasts over 2000 aroma compounds, with sulfur-containing compounds being the most influential in shaping its flavor. Benzenemethanethiol, a distinctive odorant in baijiu, is known to enhance the holistic flavor profile of baijiu. Despite its importance, there is very little literature on the biotransformation mechanism of benzenemethanethiol. Thus, extensive research efforts have been made to elucidate the formation mechanism of this compound in order to improve baijiu production. In this study, 12 yeast strains capable of generating benzenemethanethiol were isolated from baijiu daqu, and the Saccharomyces cerevisiae strain J14 was selected for further investigation. The fermentation conditions were optimized, and it was found that the optimal conditions for producing benzenemethanethiol were at 28 °C for 24 h with a 4% (v/v) inoculum of 3.025 g/L L-cysteine. This is the first time that yeast has been shown to produce benzenemethanethiol isolated from the baijiu fermentation system. These findings also suggest that benzenemethanethiol can be metabolized by yeast using L-cysteine and benzaldehyde as precursor substrates.

ACE inhibitory activity and salt-reduction properties of umami peptides from chicken soup.

Angiotensin-I-converting enzyme (ACE) inhibitory activity and salt-reduction properties of umami peptides identified in chicken soup were investigated. The ACE inhibition rate of TPLVDR (91.22%) and AEINKILGN (81.26%) was significantly higher than other umami peptides, and their semi-inhibitory concentration was 0.017 mM and 0.034 mM, respectively. After in vitro digestion, the inhibitory activity of AEINKILGN and TPLVDR decreased, but the original sequences were still detected. The docking results showed that AEINKILGN and TPLVDR mainly interacted with Zn2+ and key sites (His353, Lys511and Glu411) in the active pockets of ACE through hydrogen bonds, which was crucial to the ACE inhibitory activity. Based on response surface methodology and sensory analysis, saltiness and palatability models were established to investigate the salt-reduction effect. The optimal level of AEINKILGN was about 1.16 mg/mL in 0.44% salt solution. And the TPLVDR was applicable to the low salt solution (0.1-0.2%) at a concentration from 0.23 to 0.29 mg/mL.

Identification of Novel Umami Peptides in Chicken Breast Soup through a Sensory-Guided Approach and Molecular Docking to the T1R1/T1R3 Taste Receptor.

Ultrafiltration combined with nanoliquid chromatography quadrupole time-of-flight mass spectrometry (nano-LC-QTOF-MS) and sensory evaluation was used to separate and identify umami peptides in chicken breast soup. Fifteen peptides with umami propensity scores of >588 were identified from the fraction (molecular weight ≤1 kDa) using nano-LC-QTOF-MS, and their concentrations ranged from 0.02 ± 0.01 to 6.94 ± 0.41 µg/L in chicken breast soup. AEEHVEAVN, PKESEKPN, VGNEFVTKG, GIQKELQF, FTERVQ, and AEINKILGN were considered as umami peptides according to sensory analysis results (detection threshold: 0.18-0.91 mmol/L). The measurement of point of subjective equality showed that these six umami peptides (2.00 g/L) were equivalent to 0.53-0.66 g/L of monosodium glutamate (MSG) in terms of umami intensity. Notably, the sensory evaluation results showed that the peptide of AEEHVEAVN significantly enhanced the umami intensity of the MSG solution and chicken soup models. The molecular docking results showed that the serine residues were the most frequently observed binding sites in T1R1/T1R3. The binding site Ser276 particularly contributed to the formation of the umami peptide-T1R1 complexes. The acidic glutamate residues observed in the umami peptides were also involved in their binding to the T1R1 and T1R3 subunits.

Oat ß-glucan alleviates muscle atrophy via promoting myotube formation and suppressing protein degradation.

BACKGROUND: The dangerous inducers of muscle atrophy are inflammatory reaction, oxidative stress, and cachexia, etc. ß-Glucan, an important food derived active ingredient, has been reported to exert anti-inflammatory effects, however, its effects on regulating myoblast differentiation and protein degradation are unclear. This study is aimed to investigate the mechanism of oat ß-glucan on alleviating muscle atrophy. RESULTS: The results showed that oat ß-glucan treatment reversed tumor necrosis factor-α (TNF-α) induced abnormal myoblast differentiation and reduced muscle atrophy related MuRF-1 and Atrogin-1 protein expression. The similar phenomenon was observed after using MCC950 (NLRP3 specific inhibitor) or AS1842856 (FoxO1 specific inhibitor) to suppress NLRP3 and FoxO1 expression, respectively. Exposure to ß-glucan or AS1842856 also inhibited TNF-α induced the activation of TLR4/NF-κB pathway by inactivating FoxO1, and subsequently suppressed the expression of NLRP3. CONCLUSION: Our results indicate that oat ß-glucan exerts essential roles in promoting myoblast differentiation and alleviating muscle atrophy via inactivating FoxO1 and NLRP3 inflammasome signal pathway. © 2023 Society of Chemical Industry.

Magnetically driven nanorobots based on peptides nanodots with tunable photoluminescence for rapid scavenging reactive α-dicarbonyl species and effective blocking of advanced glycation end products.

The present work constructed magnetically driven nanorobots by conjugating the photoluminescent ß-alanine-histidine (ß-AH) nanodots to superparamagnetic nanoparticles (SPNPs) for simultaneously sensitive determination and fast trapping RDS in food processing, achieving efficient regulation of advanced glycation end products (AGEs) risk. Bio-derivative ß-AH nanodots with orderly self-assembly nanostructure and tunable photoluminescent properties served as both biorecognition elements to effectively bind and scavenge the reactive α-dicarbonyl species (RDS), as well as the indicator with sensitive fluorescence response in the food matrix. The magnetically driven nanorobots with excellent biosafety of endogenous dipeptides displayed a high binding capacity of 80.12 mg g-1 with ultrafast equilibrium time. Furthermore, the magnetically driven nanorobots achieved rapid removal of the RDS with the manipulation of the external magnetic field, which enabled intercepting AGEs generation without byproducts residual as well as ease-of-operation. This work provided a promising strategy with biosafety and versatility for both accurate determination and efficient removal of hazards.

A selectivity-enhanced fluorescence imprinted sensor based on yellow-emission peptide nanodots for sensitive and visual smart detection of λ-cyhalothrin.

The development of precise and efficient detection technologies to recognize λ-cyhalothrin (LC) in agricultural products has attracted attention worldwide due to its widespread use and notable toxic effects on humans. Herein, a novel fluorescence biomimetic nanosensor was elaborately designed based on Zn(II)-doped cyclo-ditryptophan (c-WW)-type peptide nanodots and incorporating molecularly imprinted polymer (c-WW/Zn-PNs@MIP) for LC assays. C-WW/Zn-PNs obtained by self-assembly with aromatic cyclic dipeptides as basic building blocks and coordination with Zn(II) have low-toxicity, photostability, and bright yellow fluorescence emission, as a sensitive signal transducer. High-affinity imprinting sites further endow c-WW/Zn-PNs@MIP with superior selectivity and reusability. Based on prominent merits, c-WW/Zn-PNs@MIP demonstrated a good linear range (1-360 µg/L) with a low limit of detection (LOD) (0.93 µg/L), fast kinetics in target capture (10 min), and strong practicability in the capture of LC from real samples (spiked recovery of 81.0-107.7%). Additionally, to attain onsite profiling of LC, a visual platform was developed by integrating c-WW/Zn-PNs@MIP with a smartphone-assisted optical device. This smart evaluation system can capture concentration-dependent fluorescent images and accurately digitize them, enabling quantitative analysis of LC. This study developed a fluorescent c-WW/Zn-PNs@MIP-based smart evaluation system as a novel platform for LC monitoring applications, which not only has enormous economic value but also great environmental health significance.

Magnetically Controlled Nanorobots Based on Red Emissive Peptide Dots and Artificial Antibodies for Specific Recognition and Smart Scavenging of Nε-(Carboxymethyl)lysine in Dairy Products.

Food-borne advanced glycation end products (AGEs) are highly related to various irreversible diseases, and Nε-(carboxymethyl)lysine (CML) is the typical hazardous AGE. The development of feasible strategies to monitor and reduce CML exposure has become desirable to address the problems. In this work, we proposed magnetically controlled nanorobots by integrating an optosensing platform with specific recognition and binding capability, realizing specific anchoring and accurate determination as well as efficient scavenging of CML in dairy products. The artificial antibodies offered CML imprinted cavities for highly selective absorption, and the optosensing strategy was designed based on electron transfer from red emissive self-assembling peptide dots (r-SAPDs) to CML, which was responsible for the identity, response, and loading process. The r-SAPDs overcame the interference from autofluorescence, and the limit of detection was 0.29 µg L-1, which bestowed accuracy and reliability for in situ monitoring. The selective binding process was accomplished within 20 min with an adsorption capacity of 23.2 mg g-1. Through an external magnetic field, CML-loaded nanorobots were oriented, moved, and separated from the matrix, which enabled their scavenging effects and reusability. The fast stimuli-responsive performance and recyclability of the nanorobots provided a versatility strategy for effective detection and control of hazards in food.

Decoding the Effect of Age on the Taste Perception of Chicken Breast Soup Based on LC-QTOF-MS/MS Combined with a Chemometric Approach.

A nontargeted fingerprinting approach combined with the chemometrics method and sensory analysis was used to assess the differences in taste-chemical compositions of chicken breast soup with different ages and their sensory qualities. The sensory evaluation results showed that the overall taste as well as the sourness, saltiness, and umami scores of the soup were increased with the age of chicken. Fifty-nine compounds were identified from four soup samples by liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (LC-QTOF-MS/MS), and their total content was the highest in the 90 wk soup samples. Six upregulated compounds (carnosine, hypoxanthine, inosine, inosine 5'-monophosphate (5'-IMP), adenosine 5'-monophosphate (5'-AMP), and lactic acid) were identified as potential contributors to the taste characteristics of the 90 wk soup samples by orthogonal projections to latent structures-discriminant analysis (OPLS-DA). Additional experiments showed that 5'-AMP particularly contributed to the sourness of the soup, while carnosine contributed to the saltiness and umami of the soup.

Peptide-Based Molecularly Imprinted Polymer: A Visual and Digital Platform for Specific Recognition and Detection of Ethyl Carbamate.

A visual and digital platform was constructed by peptide-based molecularly imprinted polymers (PMIPs) for specific recognition and detection of ethyl carbamate (EC). Here, the optosensing core was creatively constructed by the covalent assembly of dipeptides (H-Phe-Phe-OH) and genipin biomolecules for high fluorescence quantum yield and dual-signal response capability. MIPs were wrapped in the shell of the optosensing core for selectivity of EC from actual samples of alcoholic beverages. The genipin-FF nanoparticles (GFPNs)@PMIPs exhibited dual-band red-blue fluorescence image with a low detection limit of 0.817 and 1.65 µg L-1, respectively, in the optimal linear range of 2-240 µg L-1. The accuracy of this method was verified by the spiked recovery experiment, and a good recovery from 83.97 to 106.75% of the proposed optosensing method was obtained. In addition, a smartphone application was coupled with GFPNs@PMIPs to realize online real-time detection of EC. With the addition of EC, the color change of G and B values was negligible compared with the R value. This work also provides a potential method for on-site visual detection of analytes.

A fast stop-flow two-dimensional liquid chromatography tandem mass spectrometry and its application in food-derived protein hydrolysates.

Food-derived bioactive peptides have many outstanding features like high safety, easy absorption, etc. However, explorations of the peptides are suffering from the limited knowledge of sample composition and low efficiency of separation techniques. In this work, a fast stop-flow two-dimensional liquid chromatography tandem mass spectrometry (2DLC-MS) was designed and constructed in-house. For chromatographic system optimization, the effects of column pairs and fraction transfer volumes on separation performance were studied. The pair of Protein BEH SEC and HSS T3 columns was found of high orthogonality. The peak capacity detected by the optimized 2DLC reached 1165 (for corn protein hydrolysates), indicating high resolving power. Moreover, the number of peptides identified from corn, soybean and casein protein hydrolysates reached as high as 8330, 8925 and 7215, respectively, demonstrating the high potential of the system. This would help reveal the peptide composition and facilitate the research on exploring bioactive peptides from food-derived protein hydrolysates.