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The increase in lactose intolerance, the rise of veganism, the pursuit of healthy lifestyles, environmental awareness and concern for animal welfare have led to an increase in consumer demand for plant-based yogurts. The high nutritional value of nuts makes them an ideal ingredient for the production of plant-based yogurts. The main challenge for such products is to achieve a similar taste to traditional yogurt while improving shelf life. In recent years, extensive research has been conducted on this topic. The nutritional and health properties of yogurts made from different types of nuts, traditional and innovative processing technologies, and the effects of fermentation on the nutritional value, sensory characteristics, and texture of the yogurts are described. This review provides a comprehensive overview of the nutritional and manufacturing process of nut yogurts and offers possible directions for development and innovation of health food products.

Legume proteins have recently gained significant interest in the food industry for their eco-friendliness and nutritional qualities. Research shows that the replacement of specific animal protein sources with legume proteins presents sustainability and economic benefit. Nonetheless, legume proteins frequently exhibit inferior functional properties and palatability compared to animal proteins. Various non-thermal technologies, including high hydrostatic pressure, ultrasound, cold plasma, pulsed electric field, and dynamic high-pressure microjet, had been investigated to enhance the functional properties of legume proteins without loss of nutritional and sensory properties. Although these technologies show potential, no systematic study has been conducted to summarize and compare their effects on different legume proteins. This review aims to fill this gap by addressing the most promising approaches of non-thermal technologies for the modification of functional properties of legume proteins. New insights are discussed, elaborating the effect of non-thermal technologies on the structural and functional behavior of proteins.

Fruits are recognized as healthy foods with abundant nutritional content. However, due to their high content of sugar and water, they are easily contaminated by microorganisms leading to spoilage. Probiotic fermentation is an effective method to prevent fruit spoilage. In addition, during fermentation, the probiotics can react with the nutrients in fruits to produce new derived compounds, giving the fruit specific flavor, enhanced color, active ingredients, and nutritional values. Noteworthy, the choice of fermentation strains and strategies has a significant impact on the quality of fermented fruits. Thus, this review provides comprehensive information on the fermentation strains (especially yeast, lactic acid bacteria, and acetic acid bacteria), fermentation strategies (natural or inoculation fermentation, mono- or mixed-strain inoculation fermentation, and liquid- or solid-state fermentation), and the effect of fermentation on the shelf life, flavor, color, functional components, and physiological activities of fruits. This review will provide a theoretical guidance for the production of fermented fruits.

Edible mushrooms are high in nutrients, low in calories, and contain bioactive substances; thus, they are a valuable food source. However, the high moisture content of edible mushrooms not only restricts their storage and transportation after harvesting, but also leads to a shorter processable cycle, production and processing limitations, and a high risk of deterioration. In recent years, ultrasonic technology has been widely applied to various food production operations, including product cleaning, post-harvest preservation, freezing and thawing, emulsifying, and drying. This paper reviews applications of ultrasonic technology in the production and processing of edible mushrooms in recent years. The effects of ultrasonic technology on the drying, extraction of bioactive substances, post-harvest preservation, shelf life/preservation, freezing and thawing, and frying of edible mushrooms are discussed. In summary, the application of ultrasonic technology in the edible mushroom industry has a positive effect and promotes the development of this industry.

Tilapia skin gelatin hydrolysates (TSGH) were obtained by complex protease hydrolysis. The amino acid sequences of 50 peptides in TSGH were identified, and most of these peptides were found to contain the -Gly-Pro-sequence. The osteoporosis (OP) rat model induced by retinoic acid was prepared, and the effects of different doses of TSGH on OP in vivo were evaluated. Serum calcium (Ca) and phosphate (P), alkaline phosphatase activity, and osteocalcin levels in OP rats were regulated by TSGH. The bone length, dry weight index, maximum load, and Ca content of OP rats significantly increased by treatment TSGH in a dose-dependent manner. Micro-CT images of the femurs and tibias of the rats indicated that the bone mineral density, cortical bone thickness, and cortical/trabecular bone area ratios were recovered and that OP symptoms were improved. Tartrate-resistant acid phosphate and hematoxylin-eosin staining showed that osteoclast numbers and histomorphological changes in the femurs in OP rats could be recovered by TSGH.

Previous study showed KYPHVF has a high angiotensin-converting enzyme (ACE) inhibitory activity. This study aimed to further explore the in vitro simulated gastrointestinal digestion stability, in vivo antihypertensive, and network pharmacology of KYPHVF. Results showed that KYPHVF was stable during simulated gastrointestinal digestion in vitro. KYPHVF was absorbed in intact form by Caco-2 cell monolayer with a transport percentage of 2.00%, and KYPHVF was partially hydrolyzed to produce YPHVF and PHVF through the Caco-2 cell monolayer. The blood pressures of Spontaneous hypertensive rats (SHRs) decreased after the oral administration of KYPHVF, and KYPHVF might produce antihypertensive effect by lowering the ACE contents of serum and kidney in SHRs. Furthermore, the results of network pharmacology indicated that KYPHVF had 44 potential antihypertensive targets, showing multi-target and multi-pathway antihypertensive characteristics. Molecular docking results showed that KYPHVF had strong binding force and affinity with key antihypertensive targets.

Abstract Food safety as a public health issue has aroused worldwide concern. Food safety risks caused by the existence of food safety hazards in food may occur in all stages of the food supply chain. Thus, great emphasis is placed on sensitive, selective, and convenient analytical methods of various food safety hazards in food. At present, nanomaterials are at the forefront of various electrochemical sensing applications. Given their unique physical, chemical, and biological characteristics, nanomaterials are considered perfect candidates for the design of electrode surface to construct electrochemical sensors with excellent analytical performance. With the assistance of nanomaterials, electrochemical sensors are a potential alternative to conventional methods of food safety analysis. This review focuses on current research achievements of nanomaterial‐assisted electrochemical sensors for food safety analysis reported in recent 5 years. It highlights the different detection mechanisms for analytes, flexible sensing strategies based on nanomaterials, and portable miniaturized electrochemical devices. Finally, the challenges and limitations in the design of electrochemical sensors for food safety analysis are also discussed.

Hypomyces chrysospermus is a fungal parasite that grows on Boletus species. One isolated strain of H. chrysospermus from B. griseus was obtained and proved of strong ability to tolerate and absorb cadmium (Cd) by previous research. However, the molecular mechanisms of underlying the resistance of H. chrysospermus to Cd stress have not been investigated. This study aimed to assess the effect of Cd stress on the global transcriptional regulation of H. chrysospermus. A total of 1,839 differentially expressed genes (DEGs) were identified under 120 mg/l Cd stress. Gene ontology (GO) enrichment analysis revealed that large amounts of DEGs were associated with cell membrane components, oxidoreductase activity, and transport activity. KEGG enrichment analysis revealed that these DEGs were mainly involved in the translation, amino acid metabolism, transport and catabolism, carbohydrate metabolism, and folding/sorting and degradation pathways under Cd stress. Moreover, the expression of DEGs encoding transporter proteins, antioxidant enzymes, nonenzymatic antioxidant proteins, detoxification enzymes, and transcription factors was associated with the Cd stress response. These results provide insights into the molecular mechanisms underlying Cd tolerance in H. chrysospermus and serve as a valuable reference for further studies on the detoxification mechanisms of heavy metal-tolerant fungi. Our findings may also facilitate the development of new and improved fungal bioremediation strategies.

In today’s food industry, the potential of bioactive compounds in preventing many chronic diseases has garnered significant attention. Many delivery systems have been developed to encapsulate these unstable bioactive compounds. Emulsion gels, as colloidal soft-solid materials, with their unique three-dimensional network structure and strong mechanical properties, are believed to provide excellent protection for bioactive substances. In the context of constructing carriers for bioactive materials, proteins are frequently employed as emulsifiers or gelling agents in emulsions or protein gels. However, in emulsion gels, when protein is used as an emulsifier to stabilize the oil/water interface, the gelling properties of proteins can also have a great influence on the functionality of the emulsion gels. Therefore, this paper aims to focus on the role of proteins’ emulsifying and gelling properties in emulsion gels, providing a comprehensive review of the formation and modification of protein-based emulsion gels to build high-quality emulsion gel systems, thereby improving the stability and bioavailability of embedded bioactive substances.

The effect of different ultrasound pretreatment powers (0–500 W) before hot air drying on the moisture migration and quality of Cantharellus cibarius (C. cibarius) was investigated in this study. The results showed that the ultrasound pretreatment accelerated the drying rate. When the ultrasound power was 400 W, the drying time of C. cibarius was reduced by 18.90% compared with the control group. The low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) results showed that the ultrasound pretreatment increased the water mobility in C. cibarius. The scanning electron microscopy (SEM) results revealed that the ultrasound pretreatment promoted the expansion of intercellular pores. In addition, the rehydration capacity and quality characteristics of the ultrasound-pretreated dried C. cibarius were better than those of the control group. Overall, this study concluded that ultrasound pretreatment is a promising pretreatment method for the hot air drying of C. cibarius products to reduce the total drying time significantly and improve the retention rate of the total phenolics and flavonoids of dried C. cibarius.

The addition of food-derived antihypertensive peptides to the diet is considered a reasonable antihypertension strategy. However, data about the stability of antihypertensive peptides in different food processing conditions are limited. In this study, through Sephadex G-15 gel chromatography and RP-HPLC separation, UPLC–ESI–MS/MS analysis and in silico screening, two novel ACE-inhibitory peptides, Pro-Leu-Leu-Lys (IC50: 549.87 μmol/L) and Pro-Pro-Met-Trp-Pro-Phe-Val (IC50: 364.62 μmol/L), were identified in millet bran glutelin-2 hydrolysates. The inhibition of angiotensin-I converting enzyme and the potential safety of PLLK and PPMWPFV were studied using molecular docking and in silico prediction, respectively. The results demonstrated that PLLK and PPMWPFV could non-competitively bind to one and seven binding sites of ACE through short hydrogen bonds, respectively. Both PLLK and PPMWPFV were resistant to different pH values (2.0–10.0), pasteurization conditions, addition of Na+, Mg2+ or K+ and simulated gastrointestinal digestion. However, PLLK and PPMWPFV were unstable upon heat treatment at 100 °C for more than 20 min or treatment with Fe3+ or Zn2+. In fact, treatment with Fe3+ or Zn2+ induced the formation of PLLK–iron or PLLK–zinc chelates and reduced the ACE-inhibitory activity of PLLK. These results indicate that peptides derived from millet bran could be added to foods as antihypertension agents.

Fungi bioaccumulation of heavy metals is a promising approach to remediate polluted soil and water. Boletus griseus could accumulate high amounts of Cd, even in a natural habitat with low Cd contents. This study found a symbiotic association of B. griseus with a fungus. The symbiotic fungus was isolated and identified as Hypomyces chrysospermus. The isolated strain had a strong ability to tolerate Cd. The minimum inhibitory concentration of Cd of fungal growth was 200 mg·L−1. The Cd bioaccumulation capacity of the fungus reached 10.03 mg·g−1. The biomass production of the fungus was promoted by 20 mg·L−1 Cd. However, high concentrations of Cd suppressed fungal growth and significantly altered the morphology and fine texture of fungal hyphae and chlamydospores. The immobilization effects of the cell wall and acid compounds and antioxidant enzymes were employed by the fungus to alleviate the toxic effects of Cd. The results not only demonstrate a new insight into the Cd bioconcentration mechanisms of B. griseus but also provide a potential bioremediation fungus for Cd contamination.

In this study, a calcium-binding peptide was obtained by hydrolyzing tilapia bone and its osteogenic activity was evaluated. Animal protease was selected from nine enzymes, and its hydrolysate was purified through preparative and semi-preparative reverse phase high-performance liquid chromatography. The purified peptide was identified as DGPSGPK (656.32 Da) and its calcium-binding capacity reached 111.98 µg/mg. The peptide calcium chelate (DGPSGPK-Ca) was obtained, and its structure was characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and mass spectrometry (MS). The results of XRD and SEM showed that DGPSGPK-Ca was formed as a new compound. The carboxyl and amino groups of Lys and Asp residues may be the chelating sites of DGPSGPK according to the FTIR and MS results. The molecular simulation showed the carbonyl groups of Asp, Pro, Ser, and Lys residues involved in the binding of calcium. The interaction of DGPSGPK and different integrins was evaluated by molecular docking simulation, and the main forces involved were electrostatic interaction forces, hydrogen bonding and hydrophobic interactions. Furthermore, DGPSGPK could inhibit the differentiation of osteoclast and promote the proliferation, differentiation and mineralization of osteoblasts.

Rape bee pollen possesses many nutritional and therapeutic properties because of its abundant nutrimental and bioactive components. In this study, free (FPE) and bound (BPE) phenolic extracts of rape bee pollen were obtained, phenolic and flavonoid contents were determined, and composition of phenolic acids was analyzed. In vitro antioxidant and anti-tyrosinase (TYR) activities of FPE and BPE were compared, and inhibitory melanogenesis of FPE was further evaluated. Results showed FPE and BPE contain total phenolic contents of 11.76 and 0.81 mg gallic acid equivalents/g dry weight (DW) and total flavonoid contents of 19.24 and 3.65 mg rutin equivalents/g DW, respectively. Phenolic profiling showed FPE and BPE fractions contained 12 and 9 phenolic acids, respectively. FPE contained the highest rutin content of 774.87 μg/g. FPE and BPE showed the high antioxidant properties in vitro and high inhibitory activities for mushroom TYR. Higher activities of FPE than those of BPE can be attributed to difference in their phenolic compositions. Inhibitory melanogenesis activities of FPE against B16 were further evaluated. Results showed suppressed intracellular TYR activity, reduced melanin content, and promoted glutathione synthesis (p < 0.05) in FPE-treated cells. FPE reduced mRNA expression of TYR, TYR-related protein (TRP)-1 and TRP-2, and significantly suppressed cyclic adenosine monophosphate (cAMP) levels through down-regulation of melanocortin 1 receptor gene expression (p < 0.05). FPE reduced mRNA expression of microphthalmia-associated transcription factor (MITF), significantly inhibiting intracellular melanin synthesis (p < 0.05). Hence, FPE regulates melanogenesis of B16 cells involved in cAMP/MITF/TYR pathway. These results revealed that FPE can be used as pharmaceutical agents and cosmetics to protect cells from abnormal melanogenesis.

The peptide QAGLSPVR, which features high angiotensin-I-converting enzyme (ACE) inhibitory activity, was identified in our previous study. In this study, the in vivo antihypertensive effect of QAGLSPVR was evaluated. Results showed that QAGLSPVR exerts a clear antihypertensive effect on spontaneously hypertensive rats (SHRs), and the systolic and diastolic blood pressures of the rats remarkably decreased by 41.86 and 40.40 mm Hg, respectively, 3 h after peptide administration. The serum ACE activities of SHRs were determined at different times, and QAGLSPVR was found to decrease ACE activities in serum; specifically, minimal ACE activity was found 3 h after administration. QAGLSPVR could be completely absorbed by the Caco-2 cell monolayer, and its transport percentage was 3.5% after 2 h. The transport route results of QAGLSPVR showed that Gly-Sar and wortmannin exert minimal effects on the transport percentage of the peptide (p> 0.05), thus indicating that QAGLSPVR transport through the Caco-2 cell monolayer is not mediated by peptide transporter 1 or transcytosis. By contrast, cytochalasin D significantly increased QAGLSPVR transport (p< 0.05); thus, QAGLSPVR may be transported through the Caco-2 cell monolayer via the paracellular pathway.

In this study, the effect of tilapia gelatin peptides (TGP) on UV-induced damages to mice skin was evaluated. The antioxidant indicators, lipid, collagen and glycosaminoglycan of mice skin were determined and histological changes of the collagen were depicted. The results showed TGP could alleviate the UV-induced abnormal changes of antioxidant indicators, and the protective effect was in dose-dependent manners. TGP could protect skin lipid and collagen from the UV radiation damages, and the change of glycosaminoglycan was also recovered significantly. The action mechanisms of TGP mainly involved the antioxidant properties and the repairing to endogenous collagen synthesis. Therefore, the key antioxidant peptide was further purified from TGP. Finally, one antioxidant peptide was identified and the amino acid sequence was Leu-Ser-Gly-Tyr-Gly-Pro (592.26 Da). The IC50 value of this peptide on hydroxyl radical scavenging activity was 22.47 μg/mL. TGP could be a novel antiphotoaging agent from natural resources.

Tilapia frame protein was hydrolyzed by different proteases, including properase E, pepsin, trypsin, flavourzyme, neutrase, gc106 and papain, to obtain antioxidant peptides. The tilapia frame protein hydrolysate (TFPH) obtained by trypsin exhibited the highest degree of hydrolysis and antioxidant activity. Three series of peptides (TFPH1, TFPH 2 and TFPH 3) were obtained by ultrafiltration of TFPH through molecular weight cut-off membranes of 5, 3 and 1 kDa, respectively, and their IC50 values on scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (•O2), hydrogen peroxides (H2O2) and hydroxyl radical (•OH) activities were determined and compared with glutathione (GSH). The results showed that TFPH1 had the highest antioxidant activity. TFPH1 was further purified using ion exchange chromatography, gel filtration chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). Finally, two antioxidant peptides were identified and the amino acid sequences were identified as Asp-Cys-Gly-Tyr (456.12 Da) and Asn-Tyr-Asp-Glu-Tyr (702.26 Da), respectively. The IC50 values of two peptides on hydroxyl radical scavenging activity were 27.6 and 38.4 μg/mL, respectively.

Antihypertensive effect of long-term oral administration of jellyfish (Rhopilema esculentum) collagen peptides (JCP) on renovascular hypertension rats (RVHs) was evaluated. The systolic blood pressure and diastolic blood pressure of the RVHs were significantly reduced with administration of JCP (p < 0.05), compared with model control group. However, the arterial blood pressure of normal rats showed no significant changes during long-term oral treatment with high dose JCP (p > 0.05). Furthermore, effect of JCP on angiotensin II (Ang II) concentration of plasma had no significance (p > 0.05), but JCP significantly inhibited the Ang II concentration in RVHs’ kidney (p < 0.05). The kidney should be the target site of JCP.

The contents of bioactive compounds (Vitamin C (Vc), carotenoids, total phenolics, phenolic profiles and capsaicinoids) and antioxidant activities (reducing power, DPPH·-scavenging activity and lipid peroxidation inhibition ability) of nine peppers from Yunnan province China, belonging to seven cultivars, were determined. Red and green Point pepper/Long-point pepper were from the same cultivars at different maturity stages. Results showed that all fresh pepper samples were rich in Vc, carotenoids, and total phenolics. Vc contents varied mainly depending on the pepper cultivars, except for the ripened stages. The phenolic content in red Fructus Capsici (Capsium frutescens L.) was significantly higher than that of others (Capsium annuum L.) (p

Whereas the preparation and biological properties of rambutan peel phenolics (RPP) were explored in our previous studies, the metal chelating, inhibitory DNA damage, and anti-inflammatory activities of RPP were evaluated and the important phenolics of RPP quantified in this study. Results showed that RPP had high Fe2+ and Cu2+-chelating activities with EC50 of 0.80 mg/mL and 0.13 mg/mL, respectively. RPP effectively decreased the production of hydroxyl radical with IC50 of 62.4 μg/mL. The protective effects of RPP against AAPH-induced DNA damage were also explored. RPP efficiently inhibited peroxyl radical-induced plasmid DNA strand breakage. The anti-inflammatory effects of RPP were determined using a lipopolysaccharide (LPS)-induced RAW 264.7 cell model. RPP significantly inhibited the production of nitric oxide (NO) and controlled the levels of inducible NO synthase mRNA in LPS-induced RAW 264.7 cells. The inhibitory activity increased in a dose-dependent manner. The above bioactivity of RPP was associated with its phenolic content and phenolic profiles. Furthermore, the contents of geraniin and corilagin in RPP were determined by an ultra-high performance liquid chromatography coupled with triple quadruple mass spectrometry (UPLC-QQQ-MS), showing 140.02 and 7.87 mg/g extract dry weight. Thus, RPP has potential applications as a novel nutraceutical and functional food in health promotion.

In this study, the stable collagen hydrolysate was prepared by alcalase hydrolysis and twice simulated gastrointestinal digestion from Alaska pollock skin. The characteristics of hydrolysates and antioxidant activities in vitro, including 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS•+) scavenging activity, ferric-reducing antioxidant power (FRAP) and hydroxyl radical (OH·) scavenging activity, were determined. After twice simulated gastrointestinal digestion of skin collagen (SGI-2), the degree of hydrolysis (DH) reached 26.17%. The main molecular weight fractions of SGI-2 were 1026.26 and 640.53 Da, accounting for 59.49% and 18.34%, respectively. Amino acid composition analysis showed that SGI-2 had high content of total hydrophobic amino acid (307.98/1000). With the simulated gastrointestinal digestion progressing, the antioxidant activities increased significantly (p < 0.05). SGI-2 was further purified by gel filtration chromatography, ion exchange chromatography and high performance liquid chromatography, and the A1a3c–p fraction with high hydroxyl radical scavenging activity (IC50 = 7.63 μg/mL) was obtained. The molecular weights and amino acid sequences of key peptides of A1a3c–p were analyzed using high resolution mass spectrometry (LC-ESI-LTQ-Orbitrap-MS) combined with de novo software and UniProt of MaxQuant software. Four peptides were identified from A1a3c–p, including YGCC (444.1137 Da) and DSSCSG (554.1642 Da) identified by de novo software and NNAEYYK (900.3978 Da) and PAGNVR (612.3344 Da) identified by UniProt of MaxQuant software. The molecular weights and amino acid sequences of four peptides were in accordance with the features of antioxidant peptides. The results indicated that different peptides were identified by different data analysis software according to spectrometry mass data. Considering the complexity of LC-ESI-LTQ-Orbitrap-MS, it was necessary to use the different methods to identify the key peptides from protein hydrolysates.

BACKGROUND Hypertension and diabetes are two kinds of senile diseases which often occur simultaneously. The commonly used drugs in clinic may produce certain side effects. Food‐derived polypeptide is a kind of polypeptide with great development potential, which has many functions of regulating human physiological function. Beer is rich in nutrition but there are few researches on bioactive peptides in beer. RESULTS: In this study, a rapid virtual screening method was established to obtain bioactive peptides from Tsingtao draft beer. The peptide sequence was analyzed by ultra‐performance liquid chromatography‐quadrupole‐Orbitrap‐tandem mass spectrometry (UPLC‐Q‐Orbitrap‐MS2), and 50 peptides were identified. Eight peptides with potential biological activities were screened by using Peptide Ranker software and previous literature references. On the basis of absorption prediction, toxicity prediction, and molecular docking analysis, LNFDPNR and LPQQQAQFK were finally confirmed. The molecular docking results showed that two peptides could bind angiotensin‐converting enzyme (ACE) and dipeptidyl peptidase IV (DPP‐IV) tightly by hydrogen bonding and hydrophobic interaction. The in vitro activity evaluation results showed that two peptides had obvious ACE and DPP‐IV inhibitory activity. CONCLUSION: This study established a method for rapidly screening bioactive peptides from Tsingtao draft beer, screened two ACE and DPP‐IV inhibitory peptides in beer and analyzed their active action mechanism. This article may have great theoretical significance and practical value to further explore the health function of beer. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Effects of carboxymethylation, hydroxypropylation and dual‐enzyme hydrolysis combined with heating on in vitro hypoglycaemic properties of coconut cake dietary fibre (CCDF) were studied. Results showed that all the three modification methods could effectively improve (P < 0.05) the glucose‐adsorption ability (GAA), glucose dialysis retardation index (GDRI), α‐glucosidase and α‐amylase inhibition activity of CCDF. The highest GAA (4.45–4.93 mm g−1), GDRI (85.09–86.94% mm g−1) and α‐glucosidase inhibition activity (16.39–19.37%) were found on CCDFs modified by hydroxypropylation and carboxymethylation, attributed to the increased soluble dietary fibre content, viscosity and water retention and swelling capacity. Moreover, CCDF treated by enzymatic hydrolysis combined with heating demonstrated the highest α‐amylase inhibition activity (53.95%), attributed to the high specific surface area, more porous surface structure and formation of fibre–amylase complex proved by fluorescence spectroscopy. These results suggest that the modified CCDFs could be used as low‐calorie functional ingredients in food or other industries. [ABSTRACT FROM AUTHOR]

Moringa oleifera leaf acetone extract (MLE) was prepared. Phytochemicals of MLE and their antioxidant, antibacterial, and anti-inflammatory activities were evaluated. Results showed that MLE contained total phenolic content of 20.16 mg gallic acid equivalents/g dry weight. A total of 39 compounds were identified by mass spectrometry. The contents of acetyl-glucomoringin, caffeoylquinic acid, feruloylquinic acid, and coumarylquinic acid were high. MLE had high DPPH· and ABTS•+ scavenging activities and reducing powder. In addition, MLE could effectively inhibit S. aureus and B. subtilis, but little effect on E. coli was found. The anti-inflammatory effect of MLE was evaluated using a lipopolysaccharide (LPS) -induced RAW 264.7 cell model. MLE significantly inhibited nitric oxide (NO) production and inducible NO synthase (iNOS) mRNA levels in LPS-induced RAW 264.7 cells. The inhibitory activity increased in a dose-dependent manner. The bioactivities of MLE were related to its phenolic content and phenolic profiles. [ABSTRACT FROM AUTHOR]

The aim of this study was to isolate and identify the peptides with calcium‐binding capacity from the different tilapia skin gelatin enzymatic hydrolysates. The complex protease was selected and its hydrolysates were further separated using gel filtration chromatography (Sephadex G‐25) and reverse phase high‐performance liquid chromatography. Two purified peptides with strong calcium‐binding capacity were identified as Tyr‐Gly‐Thr‐Gly‐Leu (YGTGL, 509.25 Da) and Leu‐Val‐Phe‐Leu (LVFL, 490.32 Da). The calcium‐binding capacities of YGTGL and LVFL reached 76.03 and 79.50 µg/mg, respectively. The structures of the complex of purified peptides and calcium (YGTGL‐Ca and LVFL‐Ca) were characterized by ultraviolet‐visible spectroscopy (UV‐VIS), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and mass spectrometry (LC‐MS/MS). The results of UV‐VIS, SEM, and XRD indicated that YGTGL‐Ca and LVFL‐Ca were formed as new compounds. The results of FTIR and LC‐MS/MS indicated the nitrogen atom of the amino group and the oxygen atom of the carboxyl group in terminates of the peptides provided primary binding sites. Moreover, the hydrophobic amino acids in purified peptides could provide more chelating spaces. This study was of great significance for the development of calcium supplement foods. Practical Application: Compared with inorganic calcium and organic calcium, the bioactive gelatin peptide chelated calcium has the characteristics of high utilization rate, high solubility, and high absorption rate. The raw materials are extracted from the tilapia processed waste, which reduce the cost, make full use of resources, and improve the bioavailability. The tilapia skin gelatin peptide calcium chelate can be directly absorbed by the human body, and the absorption efficiency is high, further improving the resource utilization rate and having high economic benefits, which is a comprehensive supplement that can also be used as a functional food. [ABSTRACT FROM AUTHOR]

The crude rambutan peel phenolic (RPP) extracts were purified by resin adsorption technology. NKA-9 resin with the best adsorption capacity and desorption ratio was chosen to dynamically purify crude RPP. Adsorption capacity and desorption ratio of NKA-9 resin were 91.85 mg gallic acid equivalent (GAE) g−1 and 90.45%, respectively. Purification processes enriched total phenolic content, and the contents in crude and purified RPP were 579.72 and 877.11 mg GAE g−1 extract powder, respectively. Phytochemical compounds of RPP were qualitatively and quantitatively indentified by mass spectrometry. Purification of the resin as expected elevated the concentrations of major phenolic compounds, especially geraniin and ellagic acid. Antioxidant and antiglycation activities of crude and purified fractions were evaluated in vitro. Crude and purified RPP had high inhibitory effects on oxidation and glycation, and purified RPP showed stronger bioactivity than crude RPP ( P < 0.05), which might be due to their differences in phenolic profiles. [ABSTRACT FROM AUTHOR]

Recent studies have shown that rambutan peel phenolic (RPP) extract demonstrate high antioxidant and antiglycation activities in vitro and in vivo. This study further evaluated the anti-diabetic activity of RPP in a mouse model of Type II diabetes induced by streptozotocin combined with high-fat diet. Results showed that RPP increased the body weight and reduced the fasting blood glucose level of the diabetic mice. RPP significantly reduced the serum levels of total cholesterol, triglyceride, creatinine, and glycated serum protein in diabetic mice in a dose-dependent manner. Glycogen content in mice liver was recovered by RPP, which further increased the activity of superoxide dismutase and glutathione peroxidase and reduced lipid peroxidation in diabetic mice. Histological analysis showed that RPP effectively protected the tissue structure of the liver, kidney, and pancreas. In addition, RPP decreased the mesangial index and inhibited the expression of TGF-β in the kidney of diabetic mice. [ABSTRACT FROM AUTHOR]

Tilapia frame protein was hydrolyzed by different proteases, including properase E, pepsin, trypsin, flavourzyme, neutrase, gc106 and papain, to obtain antioxidant peptides. The tilapia frame protein hydrolysate (TFPH) obtained by trypsin exhibited the highest degree of hydrolysis and antioxidant activity. Three series of peptides (TFPH1, TFPH 2 and TFPH 3) were obtained by ultrafiltration of TFPH through molecular weight cut-off membranes of 5, 3 and 1 kDa, respectively, and their IC50 values on scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (O2), hydrogen peroxides (H2O2) and hydroxyl radical (OH) activities were determined and compared with glutathione (GSH). The results showed that TFPH1 had the highest antioxidant activity. TFPH1 was further purified using ion exchange chromatography, gel filtration chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). Finally, two antioxidant peptides were identified and the amino acid sequences were identified as Asp-Cys-Gly-Tyr (456.12 Da) and Asn-Tyr-Asp-Glu-Tyr (702.26 Da), respectively. The IC50 values of two peptides on hydroxyl radical scavenging activity were 27.6 and 38.4 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Antihypertensive effect of long-term oral administration of jellyfish (Rhopilema esculentum) collagen peptides (JCP) on renovascular hypertension rats (RVHs) was evaluated. The systolic blood pressure and diastolic blood pressure of the RVHs were significantly reduced with administration of JCP (p < 0.05), compared with model control group. However, the arterial blood pressure of normal rats showed no significant changes during long-term oral treatment with high dose JCP (p > 0.05). Furthermore, effect of JCP on angiotensin II (Ang II) concentration of plasma had no significance (p > 0.05), but JCP significantly inhibited the Ang II concentration in RVHs' kidney (p < 0.05). The kidney should be the target site of JCP. [ABSTRACT FROM AUTHOR]

Gelatin extracted from tilapia skin was hydrolyzed with Properase E. Response surface methodology (RSM) was applied to optimize the hydrolysis condition (temperature [T], enzyme-to-substrate ratio [E/S], pH and reaction time [t]), to obtain the hydrolysate with the highest hydroxyl radical (•OH) scavenging activity. The optimum conditions obtained were T of 44.2 °C, E/S of 2.2%, pH of 9.2, and t of 3.4 h. The predicted •OH scavenging activity of the hydrolysate under the optimum conditions was 60.7%, and the actually experimental scavenging activity was 60.8%. The hydrolysate was fractionated by ultrafiltration, and 4 fractions were collected. The fraction TSGH4 (MW < 2000 Da) showed the strongest •OH scavenging activity with the highest yield. Furthermore, reactive oxygen species (ROS) scavenging activities of TSGH4 with different concentrations were investigated in 5 model systems, including superoxide anion radical (•O), •OH, hydrogen peroxide (HO), peroxynitrite (ONOO), and nitric oxide (NO•), compared with reduced glutathione (GSH). The results showed that TSGH4 significantly scavenged these ROS, and could be used as a functional ingredient in medicine and food industries. [ABSTRACT FROM AUTHOR]

To obtain hydrolysates with high degree of hydrolysis (DH) and scavenging radical activity, tilapia skin gelatin (TSG) was hydrolyzed by properase E and multifect neutral. The optimum hydrolysis condition of each enzyme was determined using the orthogonal experiment, and double-enzyme hydrolysis was further applied. The results showed the tilapia skin gelatin hydrolysate (TSGH) obtained by progressive hydrolysis using multifect neutral and properase E had the highest DH and hydroxyl radical scavenging activity. The IC50 values of TSGH on scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical (・O2) and hydroxyl radical (・OH) activities were also determined. TSGH was further purified using gel filtration chromatography, ion exchange chromatography, and RP-HPLC. The peptides were identified using nano-LC-ESI mass spectrometry. Finally, two antioxidant peptides were identified and the amino acid sequences were Glu-Gly-Leu (317.33 Da) and Tyr-Gly-Asp-Glu-Tyr (645.21 Da), respectively. The IC50 values of two peptides on hydroxyl radical scavenging activities were 4.61 μgmL−1and 6.45 μgmL−1, respectively. Therefore, the results demonstrated that the hydrolysates of TSG prepared by multifect neutral and properase E could serve as a source of peptides with high antioxidant activity. It provided a scientific basis for the preparation of antioxidant peptides. [Copyright &y& Elsevier]

• Umami peptides were the first identified from tilapia lower jaw. • STELFK, VADLMR, DALKKK, FVGLQER and VVLNPVARVE displayed umami taste characteristics. • Asp219, Glu217, and Glu148 in T1R1/T1R3 receptor play critical roles. • Hydrogen bonding and hydrophobic interaction were the important interaction forces. This study aimed to isolate and identify peptides with intense umami taste from tilapia lower jaw. The aqueous extract was separated using ultrafiltration and Sephadex G-15 gel filtration chromatography. The peptide fraction with an intense umami taste was selected by sensory evaluation. The five novel peptides with strong umami taste were VADLMR, STELFK, FVGLQER, DALKKK, and VVLNPVARVE. Electronic tongue analysis and sensory evaluation showed that five peptides had obvious umami taste characteristics, and the recognition thresholds of umami peptides were in the range 0.125–0.250 mg/mL. Molecular docking was used to study the interaction of the peptides and umami taste receptor T1R1/T1R3. The five peptides could perfectly be inserted into the binding pocket of the Venus flytrap domain in the T1R3 subunit. Hydrogen bonding and hydrophobic interaction were the important interaction forces. The five peptides may bind with Asp219, Glu217, and Glu148 in T1R1/T1R3 receptor and produce the umami taste. [ABSTRACT FROM AUTHOR]