Changes in the volatile compounds and characteristic aroma during liquid-state fermentation of instant dark tea by Eurotium cristatum.

Instant dark tea (IDT) was prepared by liquid-state fermentation inoculating Eurotium cristatum. The changes in the volatile compounds and characteristic aroma of IDT during fermentation were analyzed using gas chromatography-mass spectrometry by collecting fermented samples after 0, 1, 3, 5, 7, and 9 days of fermentation. Components with high odor activity (log2FD ≥ 5) were verified by gas chromatography-olfactometry. A total of 107 compounds showed dynamic changes during fermentation over 9 days, including 17 alcohols, 7 acids, 10 ketones, 11 esters, 8 aldehydes, 37 hydrocarbons, 4 phenols, and 13 other compounds. The variety of flavor compounds increased gradually with time within the early stage and achieved a maximum of 79 compounds on day 7 of fermentation. ß-Damascenone showed the highest odor activity (log2FD = 9) in the day 7 sample, followed by linalool and geraniol. These results indicate that fungal fermentation is critical to the formation of these aromas of IDT.

Evolutionary research trend of Polygonatum species: a comprehensive account of their transformation from traditional medicines to functional foods.

With the advances in Polygonatum research, there is a huge interest in harnessing the valuable functional ingredients of this genus with the potential for functional foods. This review emphasizes the different aspects of Ploygonatum based research starting from its bioactive compounds, their structural characterization, various extraction methods, as well as biological activities. In view of its integral use as an essential medicinal plant, our review emphasizes on its promising food applications both as an ingredient and as a whole food, and its improved health benefits with potential for agricultural and environmental relevance are also discussed. As we collated the recent research information, we present the main challenges and limitations of the current research trend in this area which can upgrade the further expansion of Polygonatum-related research that will strengthen its economic and accessible nutritional value in the food and health industries. By highlighting the need for the unattended species, this review not only fills existing research gaps, but also encourages the researchers to find new avenues for the natural production of bio-based functional materials and the development of highly functional and health-promoting foods for disease prevention and treatment.

Glycosylated peptide-calcium chelate: Characterization, calcium absorption promotion and prebiotic effect.

Finding functional preparations that could improve the bioavailability of calcium is one of the keys to solving calcium deficiency. In this study, glycosylated peptides-calcium chelate with calcium absorption promoting activity, named XOS-CSPHs-Ca-MR, was prepared from Crimson Sapper scales protein hydrolysates (CSPHs) and xylooligosaccharides (XOS) via Maillard reaction. Results showed that amino nitrogen, carboxyl oxygen, and carbonyl oxygen atom were the primary calcium chelating sites. Remarkably, XOS-CSPHs-Ca-MR exhibited good calcium phosphate crystallization inhibitory activity, gastrointestinal stability, and could promote calcium transport efficiency in the Caco-2 cell monolayer. In vitro fermentation results showed that XOS-CSPHs-Ca-MR improved the gut microbiota structure of calcium-deficient mice. Its prebiotic effect was achieved by increasing the number of beneficial bacteria, boosting the production of short-chain fatty acids, and improving the colonization ability of microbiota. Therefore, this study could lay a foundation for the study of glycosylated peptide-calcium chelate as a novel calcium supplement with prebiotic effect.

Mechanisms of the ethanol extract of Gelidium amansii for slow aging in high-fat male Drosophila by metabolomic analysis.

Gelidium amansii (GA) is a kind of red alga homologous to medicine and food and is distributed all over the world. Studies on GA are mainly focused on its polysaccharides, with little research on the ethanol extract. The ethanol extract of Gelidium amansii (GAE) was subjected to a reverse-phase column to obtain 7 components. Among them, 100% methanol solution (GAM), enriched with phytene-1,2-diol, exhibited the strongest DPPH free radical scavenging activity (IC50 = 0.17 mg mL-1). Subsequently, high-fat male flies (HMFs) were used as a model to explore the antioxidant and anti-aging effects of GAM in vivo. Studies showed that GAM can effectively prolong the lifespan of HMFs. When GAM concentrations were 0.2 and 1.0 mg mL-1, the average lifespan of HMFs was increased by 28.7 and 40.7%, respectively, while the longest lifespan of HMFs was increased by 20.55% and 32.88%, respectively. Further research revealed that GAM can significantly downregulate the levels of malondialdehyde (MDA) and protein carbonyl (PCO), and can significantly upregulate the levels of catalase (CAT) and total superoxide dismutase (T-SOD). In addition, by analyzing differential metabolites, we found that GAM relieves aging caused by oxidative stress by regulating amino acid, lipid, sugar, and energy metabolism. The GAM group significantly regulated the levels of adenine, cholic acid, glutamate, L-proline, niacin, and stachyose which tend to recover to the levels of the normal diet male fly (NMF) group. In general, our research provides ideas for the high-value utilization of GA and provides a lead compound for the research and development of anti-aging food or medicine.

Mechanical Force Induced Self-Assembly of Chinese Herbal Hydrogel with Synergistic Effects of Antibacterial Activity and Immune Regulation for Wound Healing.

Skin wounds, especially infected chronic wounds, have attracted worldwide attention due to the high prevalence and poor treatment outcomes. Hydrogel dressings with antibacterial ability and immune regulation property are urgently required. Herein, inspired by the grinding treatment of traditional Chinese medicine, mechanical force is introduced to promote the effective molecular collision and accelerate the self-assembly of chitosan (CS) and puerarin (PUE) for fabricating Chinese-herb-based hydrogels. The antibacterial rate of CS@PUE (C@P) hydrogel is more than 95%, and the wound closed rate is twice that of the control group. Interestingly, the rational design of C@P hydrogels with different PUE ratios enables a refined control over hydrogel formation, nanofiber appearance, viscoelastic, physicochemical, and biological properties. The extraordinary antibacterial ability of C@P hydrogels may originate from the nanofiber structure and the improved zeta potential on account of the orientation of amino groups in CS . Thus, the synergistically antibacterial and immune regulation properties of C@P hydrogels kill bacteria and relieve inflammation in the wound bed, ensuring the anti-infection effect, and boosting wound healing. In addition to providing a universal mechanosynthesis of PUE-based hydrogel for wound healing, this finding is expected to increase the attention paid to Chinese herbal medicines in the construction of biomaterials.

High-Throughput Identification of Organic Compounds from Polygoni Multiflori Radix Praeparata (Zhiheshouwu) by UHPLC-Q-Exactive Orbitrap-MS.

Polygoni Multiflori Radix Praeparata (PMRP), as the processed product of tuberous roots of Polygonum multiflorum Thunb., is one of the most famous traditional Chinese medicines, with a long history. However, in recent years, liver adverse reactions linked to PMRP have been frequently reported. Our work attempted to investigate the chemical constituents of PMRP for clinical research and safe medication. In this study, an effective and rapid method was established to separate and characterize the constituents in PMRP by combining ultra-high performance liquid chromatography with hybrid quadrupole-orbitrap mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS). Based on the accurate mass measurements for molecular and characteristic fragment ions, a total of 103 compounds, including 24 anthraquinones, 21 stilbenes, 15 phenolic acids, 14 flavones, and 29 other compounds were identified or tentatively characterized. Forty-eight compounds were tentatively characterized from PMRP for the first time, and their fragmentation behaviors were summarized. There were 101 components in PMRP ethanol extract (PMRPE) and 91 components in PMRP water extract (PMRPW). Simultaneously, the peak areas of several potential xenobiotic components were compared in the detection, which showed that PMRPE has a higher content of anthraquinones and stilbenes. The obtained results can be used in pharmacological and toxicological research and provided useful information for further in vitro and in vivo studies.

A Novel Stimuli-Responsive Injectable Antibacterial Hydrogel to Achieve Synergetic Photothermal/Gene-Targeted Therapy towards Uveal Melanoma.

Uveal melanoma (UM) is the most prevalent primary intraocular malignant tumor with a high lethal rate. Patients who undergo conventional enucleation treatments consistently suffer permanent blindness, facial defects, and mental disorders, therefore, novel therapeutic modalities are urgently required. Herein, an injectable and stimuli-responsive drug delivery antibacterial hydrogel (CP@Au@DC_AC50) is constructed via a facile grinding method that is inspired by the preparation process of traditional Chinese medicine. The incorporation of gold nanorods can enhance the mechanical strength of the hydrogel and realize photothermal therapy (PTT) and thermosensitive gel-sol transformation to release the gene-targeted drug DC_AC50 on demand in response to low-density near-infrared (NIR) light. The orthotopic model of UM is built successfully and indicates the excellent efficiency of CP@Au@DC_AC50 in killing tumors without damage to normal tissue because of its synergistic mild temperature PTT and gene-targeted therapy. Moreover, the eyeball infection model reveals the remarkable antibacterial properties of the hydrogel which can prevent endophthalmitis in the eyeball. There is negligible difference between the CP@Au@DC_AC50+NIR group and normal group. This NIR light-triggered gene-targeted therapy/PTT/antibacterial treatment pattern provides a promising strategy for building multifunctional therapeutic platform against intraocular tumors and exhibits great potential for the clinical treatment of UM.

Effect of grape seed power on the structural and physicochemical properties of wheat gluten in noodle preparation system.

Noodles were prepared using wheat flour supplemented with 1%, 3%, and 5% grape seed power (GSP). The farinograph properties of wheat flour, the textural properties of the dough, and thermal properties of the gluten were determined. The microstructure was analyzed by scanning electron and atomic force microscopy, and the effects of the addition of GSP on the physicochemical and structural properties (free sulfhydryl content, surface hydrophobic region, and secondary structure) of wheat gluten protein were analyzed. 1% GSP promoted the aggregation of gluten proteins by promoting hydrophobic interactions and hydrogen bonding, thus enhanced the noodle quality. Whereas, 3% and 5% GSP addition disrupted the disulfide bonds between gluten protein molecules and formed macromolecular aggregates linked to gluten proteins through non-covalent bonds and hydrophobic interactions, which prevented the formation of the gluten protein reticulation structure. Our study emphasized the interaction between wheat proteins and GSP in noodle making dough.

Radix Pseudostellariae protein-curcumin nanocomplex: Improvement on the stability, cellular uptake and antioxidant activity of curcumin.

Radix Pseudostellariae protein (RPP) with satisfactory antioxidant activity and self-assembled ability was extracted from dried Radix Pseudostellariae. In this study, RPP-curcumin nanocomplex (RPP-Cur) was fabricated, and its improvement on the stability, cellular uptake and antioxidant activity of curcumin was investigated. RPP-Cur with homogeneously spherical structure exhibited good stability, which could maintain the morphology against simulated gastrointestinal digestion and up to 300 mM ionic concentration. After RPP nanoparticles encapsulation, the retention of curcumin increased 1.45 times under UV irradiation for 6 h. Besides, RPP-Cur exhibited additive reducing power of curcumin and RPP. The transport efficiency of hydrophobic curcumin across Caco-2 cells monolayer was greatly improved by RPP nanoparticle by 3.7 folds. RPP-Cur was able to be internalized by Caco-2 cells dose-dependently via macropinocytosis and clathrin-mediated endocytosis. The cellular uptake efficiency of embedded curcumin in RPP nanoparticles by Caco-2 cells was significantly higher than that of free curcumin, which might contribute to the enhanced intracellular antioxidant activity of RPP-Cur. These findings suggest that the proteins from Radix Pseudostellariae have potential to be developed into novel delivery system with intrinsic antioxidant activity for the hydrophobic active molecules in healthy food field.

Protective effects of crimson snapper scales peptides against oxidative stress on Drosophila melanogaster and the action mechanism.

Peptides derived from crimson snapper scales (CSSPs) were reported to possess excellent free radical scavenging activities in vitro. In present study, the anti-aging and anti-oxidative stress effects of CSSPs were evaluated in Drosophila melanogaster models. Results showed that the addition of CSSPs in the diets of normal Drosophila could effectively extend their lifespan and improve the motor ability of aged Drosophila. Moreover, CSSPs could protect Drosophila from oxidative damage induced by H2O2, paraquat and UV irradiation. The extension of lifespan was found to be associated with the effects of CSSPs in improving the antioxidant defense system of Drosophila, manifesting as the reduction of oxidation products MDA and PCO, the elevated activities of T-SOD, CAT and GSH-Px, and the upregulated expression of antioxidant related genes after CSSPs supplemented. Furthermore, CSSPs at 6 mg/mL significantly downregulated mTOR signaling pathway and activated autophagy in aged male Drosophila, and the inhibition on mTOR activation was probably mediated by the antioxidant effects of CSSPs. Our findings suggest that CSSPs have the potential in making dietary supplements against natural aging and oxidative stress in organisms.

Synthesis, characterization, and biological activity of selenium nanoparticles conjugated with polysaccharides.

Nanoparticles with unique properties have potential applications in food, medicine, pharmacology, and agriculture industries. Accordingly, many significant researches have been conducted to develop novel nanoparticles using chemical and biological techniques. This review focuses on the synthesis of selenium nanoparticles (SeNPs) using polysaccharides as templates. Various instrumental techniques being used to confirm the formation of polysaccharide-SeNPs conjugates and characterize the properties of nanoparticles are also introduced. Finally, the biological activities of the synthesized SeNPs and the influence of structural factors of polysaccharides on the property of synthetic nanocomposites are highlighted. In general, the polysaccharides functionalized SeNPs can be easily obtained using sodium selenite as precursor and ascorbic acid as reductant. The final products having different particle size, morphology, and selenium content exhibit abundant physiological activities. Structural factors of polysacchairdes involving molecular weights, substitution of functional groups, and chain conformation play determinant roles on the properties of nanocomposites, resulting in different biological performances. The review on the achievements and current status of polysaccharides conjugated SeNPs provides insights into this exciting research topic for further studies in the future.

Comparative study on glucomannans with different structural characteristics: Functional properties and intestinal production of short chain fatty acids.

Glucomannans (GMs) from abundant natural resources have excellent processing properties and plentiful bioactivities. In current study, functional properties of GMs with different structural characteristics, including KGM from konjac, DOP from dendrobium, AGP40, ASP-4N, ASP-6N, & ASP-8N from aloe were determined. Results suggested that molecular weights (Mw) of GMs were positively correlated with their water absorption capacity, fat absorption capacity, and viscosity, while ratio of mannose/glucose showed negative effect. Higher degree of acetylation (DA) mainly corresponded to higher values of solubility and ζ-potential. Then, effects of the six GMs on general health status, serum biochemicals, and intestinal SCFAs production in mice were evaluated in vivo. Analysis of general health status and levels of serum biochemicals revealed that mice with consecutive supplementation of GMs for 14 days performed normally compared with those in control group. Interestingly, the productions of SCFAs (mainly acetate and butyrate) in the cecal and colonic contents were significantly promoted. Generally, higher concentrations of SCFAs were produced when mice were treated with GMs having higher Mw, ratio of glucose, and DA. The current investigation suggested that both functional and intestinal fermentation property of GMs were jointly determined by the monosaccharide composition, molecular weight, and degree of acetylation.

Comparison of phenolic compounds extracted from Diaphragma juglandis fructus, walnut pellicle, and flowers of Juglans regia using methanol, ultrasonic wave, and enzyme assisted-extraction.

The phenols in Diaphragma juglandis fructus (DJF), walnut pellicle (WP), and flowers of Juglans regia (FJR) from walnut were extracted using three methods (methanolic condensation reflux extraction, ultrasonic wave extraction, and enzyme assisted-extraction), and phenolics and antioxidant capacities of different extractions were compared. Overall, 50 phenolics were identified by HPLC-MS/MS with 41 compounds in DJF, 32 in WP, and 29 in FJR. It was observed that tannins in WP was higher than those in DJF and FJR. As for PCA, more than 70% of the variance was explained with the obvious comparison between the phenolic constituents. The phenolics in walnut contributed to remarkable antioxidant effect, with the highest effect observed in WP. This study presents the analysis and comparison of the phenols can be further extended for the development of functional walnut instant foods.

Acid-free preparation and characterization of kelp (Laminaria japonica) nanocelluloses and their application in Pickering emulsions.

Cellulose nanofibers (CNFs) from kelp were prepared by cellulase treatment with lengths greater than 3 µm. CNFs were further oxidized by TEMPO-oxidized system, and the lengths of the oxidized CNFs (TEMPO-CNFs) were 0.6-1 µm. AFM and TEM images showed that intertwined CNFs fibers were divided into individual nanofibrils. The crystallinity of TEMPO-CNFs increased to 66.5 %. TGA analysis indicated that TEMPO-CNFs were more sensitive to temperature than cellulose and CNFs. FT-IR spectra revealed no changes in the basic cellulose structures of CNFs and TEMPO-CNFs. In the sunflower oil/water (20/80, v/v) model emulsions, the oil droplet sizes were less than 20 µm in CNFs emulsions, which became smaller in TEMPO-CNFs emulsions. Delamination was found in CNFs emulsions after three days of storage. Addition of NaCl increased the volumes of TEMPO-CNFs emulsions but enlarged the oil droplets sizes. TEMPO-CNFs emulsions had the largest volume with smallest and most homogeneous oil droplets at pH 3. TEMPO-CNFs emulsions showed good stability after storage for 30 days. Further, TEMPO-CNFs could also emulsify 50 % (v/v) of sunflower oil. All these results indicated that TEMPO-CNFs can be used in preparing Pickering emulsions.

Protection against oxidative stress and anti-aging effect in Drosophila of royal jelly-collagen peptide.

Dietary peptide has been of great interest because of its perspective in nutrition and health of human body. The aim of this study was to develop a dietary nutritional supplement exerting both antioxidant and anti-aging effects. Peptide, named as ERJ-CP, was prepared by mixing enzyme-treated royal jelly (ERJ) with collagen peptide (CP), showing stronger antioxidant activity in vitro. Drosophila was used as model animal to investigate anti-aging effect of ERJ-CP in vivo. ERJ-CP significantly prolonged the average life span of Drosophila treated with H2O2 and paraquat, reducing malondialdehyde (MDA) and protein carbonyl (PCO) levels in Drosophila. In addition, 3 mg/mL of ERJ-CP could prolong the lifespan of natural aging Drosophila by 11.16%. ERJ-CP could up-regulate the levels of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and down-regulate the contents of MDA and PCO. Moreover, the intake of ERJ-CP increased the food consumption, weight gain and exercise capacity of Drosophila. The results showed that ERJ-CP played a protective role in both antioxidant and anti-aging effects on Drosophila, and the anti-aging effect may be achieved by alleviating oxidative damage. It suggests that ERJ-CP could be developed as a health-promoting ingredient with antioxidant and anti-aging effects for human body.

Nano-micelles based on hydroxyethyl starch-curcumin conjugates for improved stability, antioxidant and anticancer activity of curcumin.

In this study, amphiphilic conjugates were synthesized by conjugating curcumin (CUR) to a food-derived hydrophilic hydroxyethyl starch (HES) via an acid-labile ester linker. The self-assembly of the conjugates formed uniform micellar nanoparticles (HES-CUR NPs) with a desirable drug loading efficiency, excellent colloidal and storage stability, as well as acid-responsive release manner. Besides, the formation of the nanoparticles increased the solubility of CUR to thousands times higher than free CUR, and effectively protected the loaded CUR from degradation upon exposure to UV light and high temperature. In vitro cytotoxicity assay and radical scavenging experiments demonstrated that the HES-CUR NPs significantly improved the cytocompatibility, anticancer and antioxidant activity of CUR due to the enhanced solubility, stability, and bioavailability. The HES-CUR NPs reported herein have a great potential in developing functional food or pharmaceutical formulations for preventing or treating various diseases such as inflammatory diseases and cancer.

pH sensitive doxorubicin-loaded nanoparticle based on Radix pseudostellariae protein-polysaccharide conjugate and its improvement on HepG2 cellular uptake of doxorubicin.

Nanoparticles based on Radix pseudostellariae protein-polysaccharide conjugates were self-assembled via pH adjustment and thermal treatment. The fabricated nanoparticles (CP3) were spherical with narrow size distribution of 125.0 nm in diameter. The doxorubicin (DOX) -loaded CP3 nanoparticles exhibited pH-sensitive release behavior and accelerated the release of DOX under the acidic pH simulating tumor microenvironment and endosomal pH. In HepG2 uptake studies, CP3-DOX nanoparticles notably improved the internalization of DOX, which was 1.56-fold compared with free DOX. CP3-DOX nanoparticles could serve as P-glycoprotein efflux pump inhibitor and be internalized into HepG2 cells via clathrin-dependent endocytosis. Moreover, the cytotoxicity effect of DOX on HepG2 cells was elevated after the encapsulation by CP3, with a lower IC50 value of 0.25 µg/mL. The findings suggested that the pH-sensitive CP3-DOX nanoparticles has a great potential in facilitating the efficacy of DOX in cancer cells, and the obtained CP3 could be a good candidate as nanocarrier for the encapsulation and delivery of functional compounds.

Investigation on activation in RAW264.7 macrophage cells and protection in cyclophosphamide-treated mice of Pseudostellaria heterophylla protein hydrolysate.

Our previous study has demonstrated that Pseudostellaria heterophylla protein hydrolysate (PPH) has immunomodulatory activity on murine spleen lymphocytes. The aim of this study was to investigate the excitation of PPH in RAW264.7 macrophage cells and the protective effect in cyclophosphamide (CTX)-treated mice. The results showed PPH of 50 µg/mL could stimulate macrophages resulting in significant promotions of nitric oxide (NO) production, endocytosis and reactive oxygen species formation. Meanwhile, enzyme-linked immunosorbent assay (ELISA) revealed that the levels of tumor necrosis factor-α and interleukin-10 were significantly upregulated by PPH. Furthermore, 50 mg/kg per day PPH restored the T lymphocyte proliferation and natural killer cell activity, and increased NO production and pinocytosis of peritoneal macrophages in CTX-treated mice. These findings indicate PPH plays a crucial role in RAW264.7 macrophage cells activation and in the protection against immunosuppression in CTX-treated mice and could be used as a potential immunostimulant agent.

Organic selenium derived from chelation of soybean peptide-selenium and its functional properties in vitro and in vivo.

Organic selenium has been widely explored as an important source of selenium (Se) supplement due to its low toxicity and easy absorption. In the present study, a new type of organic selenium was fabricated by chelating Se with soybean protein isolate peptides (SPIPs), and its physio-chemical properties, structural characteristics, and antioxidant activities were investigated. Results indicated that the structure of the SPIP molecule was folded and aggregated during the chelation process. SPIP-Se exhibited stronger hydroxyl radical scavenging activity and reducing power than SPIP in vitro. In addition, SPIP-Se could repair the H2O2-induced oxidative damage of Caco-2 cells by enhancing the activities of antioxidant enzymes. The in vivo assay showed that SPIP-Se showed much less toxicity than inorganic Se supplements, and exhibited a more positive effect on the activities of key enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and aspartate aminotransferase (AST). These findings suggest that SPIP-Se could be developed as an effective dietary Se supplement in the food or pharmaceutical field in the future.

Immunomodulatory effects of Pseudostellaria heterophylla peptide on spleen lymphocytes via a Ca2+/CaN/NFATc1/IFN-γ pathway.

Pseudostellaria heterophylla has been becoming a popular research topic because of its functionally active components. The immunomodulatory activity of P. heterophylla peptide (PPH) derived from protein hydrolysate and the molecular mechanism underlying its immunomodulatory effect were investigated in this study. Immunomodulatory PPH achieved the highest stimulation index of 1.53 at a concentration of 100 µg mL-1 for 48 h in spleen lymphocytes and promoted the secretions of tumor necrosis factor-α, interferon-γ, and interleukin-10. Moreover, PPH could elevate the intracellular Ca2+ concentration, calcineurin activity and nuclear factor of activated T cell (NFAT) c1 mRNA expression. Meanwhile these effects could be diminished by the treatment of verapamil and cyclosporin A, suggesting that PPH may activate spleen lymphocytes via the Ca2+/CaN/NFATc1/IFN-γ signaling pathway. These findings demonstrate that the P. heterophylla peptide has the potential to be utilized as a nutraceutical supplement to strengthen the immune system in the human body.