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Gelatin-polysaccharide interactions have garnered significant attention in recent years due to their profound effects on the properties (rheology and structure) of various food products. This study investigates the interaction between Lycium barbarum polysaccharide (LBP) and gelatin, focusing on the impact of different concentrations LBP (0–2.0%, w/v) on gelation behavior, water mobility, and gelatin structure. The results show that the addition of LBP initially increases and then decreases the gel strength and hardness of the gelatin. Incorporating LBP into gelatin leads to decreased brightness, gelling temperature (T g), gelation rate (k gel), immobile water content, and residue, while increasing the redness, yellowness, bound and free water content, and thermal stability. Fourier transform infrared spectroscopy (FTIR), x-ray diffractometer (XRD), cryogenic scanning electron microscopy (Cryo-SEM), and atomic force microscopy (AFM) analyses provide evidence for the existence of hydrogen bonds, electrostatic interactions, and ionic bond interactions between LBP and gelatin, in addition to covalent bonds formed through the Maillard reaction. Moreover, LBP induces changes in the structure of gelatin, including alterations in secondary structure, crystalline structure, and microstructure. AFM observations further indicate that LBP promotes the formation of gelatin aggregates. These findings present promising avenues for the application of LBP-gelatin composite gels as novel materials in the food industries. [Display omitted] • Gelation behaviors and structural changes reveal LBP-gelatin interaction. • LBP-induced changes in gelatin's water mobility. • Incorporation of LBP enhances thermal stability of gelatin. • Modification of gelatin structure by LBP confirmed by FTIR, XRD, Cryo-SEM, and AFM. • LBP-gelatin interaction: Hydrogen bonds, electrostatic and ionic interactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spectroscopic and computational investigation elucidates HCQ-collagen interaction. • Collagen structure modified by HCQ binding, confirmed by XRD, FTIR, CD, and SEM. • Decreased water relaxation time observed upon HCQ-collagen interaction. • HCQ-collagen binding involves hydrophobic interactions and hydrogen bonding. • Insights into HCQ's pharmacological mechanisms for connective tissue diseases. Hydroxychloroquine sulfate (HCQ) can be used to treat various connective tissue diseases. Collagen, which is not only an important drug delivery carrier but also the main component in the connective tissue, is the focus of this study. Here, the interaction mechanism of HCQ with collagen was investigated through various spectroscopic and computational methods. It is found that HCQ binds to collagen spontaneously, primarily via hydrophobic interactions and some hydrogen bonds. The findings of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) verified that formation of HCQ-collagen complex and the amorphous structure, secondary structures, and microstructure of collagen were changed after HCQ binding. A decrease in the relaxation time of free water was observed in the collagen system when HCQ was added. Molecular docking demonstrated that HCQ was almost buried in the cavity of collagen via some hydrophobic interactions with one hydrogen bond, which conforms to the findings of the fluorescence and FTIR analyses. Molecular dynamic (MD) simulations further revealed the structural change information in the docking process. Hopefully, the information generated in this study can provide some useful insights for the research on the pharmacological mechanisms of HCQ in the treatment of the connective tissue diseases and the application of collagen as a drug carrier. [ABSTRACT FROM AUTHOR]

A novel trypsin-chymotrypsin inhibitor with thermal and pH stability, designated Glycv, was isolated from Glycine max cv. seeds. The procedure involved ammonium sulfate precipitation, ion-exchange chromatography on CM-Sephadex C-50, affinity chromatography on Affigel blue gel. The 19 N-terminal amino acid sequences were determined to be EYSKPCCDLCMCTRRCPPQ, demonstrating highly homologies with the sequence of Bowman-Birk type trypsin inhibitors. The molecular mass and isoelectric point of the inhibitor were estimated by SDS-PAGE and isoelectric focusing to be 19.7 kD and 5.8, respectively. Trypsin could be completely inhibited by Glycv when the molar ratio was 8.3. The inhibitory activity of Glycv was unaffected after exposure to temperatures up to 89 °C, as well as pH 2-12. Moreover, the inhibitor Glycv demonstrated additional antifungal activity toward the species of Fusarium oxysporum, Alternaria alternate, Physalospora piricola, Pythium aphanidermatum, Botrytis cinerea and Fusarium solani. We report, for the first time, not only the trypsin inhibitor's purification, but also its N-terminal amino acid sequence and antifungal activity against a series of phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Leguminous plants have formed a popular subject of research owing to the abundance of proteins and peptides with important biological activities that they produce. The antifungal proteins and peptides have been purified from a number of leguminous species. However, research continues to discover novel antifungal plant-produced peptides and proteins are being needed, specially those novel ones with both antifungal activity and other significant bioactivities. The objective of this study was to isolate a novel peptide from Phaseolus limensis. A 6.8 kDa peptide designated Limyin, with both antifungal and antiproliferative activity, was isolated from the large lima bean ( P. limensis) legumes. The isolation procedure consisted of extraction, precipitation, affinity chromatography on Affi-gel blue gel, ion chromatography on SP-Toyopearl, and gel filtration on Superdex 75. Its N-terminal sequence was determined to be KTCENLATYYRGPCF, showing high homology to defensin and defensin precursors from plants. It potently suppressed mycelial growth in Alternaria alternata, Fusarium solani, and Botrytis cinerea. Its antifungal activity was stable up to 80°C. It showed antiproliferative activity towards tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. However, it had no effect on bacteria Staphylococcus aureus and Salmonella. The present findings make a significant addition of the research on leguminous plants. [ABSTRACT FROM AUTHOR]

A new source of hydrogel with potential industrial application was found in Goji berry (GB) soup. The effect of preparation conditions and different salt ions (Ca2+, Na+, Mg2+) at different concentrations (3, 6, 9, and 12 mM) on the rheological properties of Goji berry gel (G‐GB) was investigated. Increases in the boiling extraction time, solid–liquid ratio, temperature, and redissolve ratio of G‐GB to ultrapure water of G‐GB increased the elastic (Gʹ) and viscous (Gʺ) modulus. Ca2+ and Mg2+ could promote the apparent viscosity, Gʹ, and Gʺ. However, Na+ minimally affected the apparent viscosity, but it decreased the Gʹ and Gʺ. Na+ and Mg2+ increased the thixotropy with increasing concentration, whereas Ca2+ first increased and then decreased thixotropy. These results indicate that G‐GB from the boiling water extract exhibited different rheological properties under different conditions and can be used as a novel processing product of GB in the food industries. Novelty impact statement: As a new approach to exploitation of popular healthy food of Goji berry (GB), a tasty edible gel (G‐GB) with different rheological properties could be prepared from the boiling water extract, indicating a possibility of developing a novel processed product of GB for the food industries. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate whether topical application of superoxide dismutase with cell penetrating peptide (HIV-TAT) could protect against skin damage induced by UVB irradiation in humans. The permeability through stratum corneum of large proteins linked to TAT peptide was firstly confirmed by confocal microscopy and tape stripping. Ten healthy volunteers with either Fitzpatrick skin type II or III were recruited in this clinical study. TAT-SOD (300 units/cm 2 ) and vehicle cream were applied on two symmetric areas of both inner upper arms 1 h prior to UVB irradiation. After one hour of pretreatment, subjects received 10 incremental doses of UVB on pretreated areas. 24 h later, erythema, blood flow and apoptotic cells were measured. Pretreatment with TAT-SOD 1 h prior to UVB radiation promoted a mean minimal erythema dose (MED) increase of 36.6 ± 18.4% ( p = 0.013 < 0.05. n = 10) compared to vehicle control. The median blood flow values of all subjects following 2 and 3-MED of UVB were 107.8 ± 51.0 units and 239.5 ± 88.0 units respectively, which account for 26% and 25% decrease with respect to vehicle groups. These data suggest that TAT-SOD significantly suppresses UVB induced erythema formation and blood flow rise. Furthermore, pretreatment with TAT-SOD 1 h prior to 2-MED of UVB irradiation reduced the apoptotic sunburn cell formation by 47.6 ± 8.6% (p < 0.0001) in all subjects. Evaluating results generated from all measurements, we conclude that topical application of TAT-SOD significantly attenuates UVB-induced skin damage in man. These biological effects of TAT-SOD are probably mediated via its free radical scavenging properties, clearly differentiating it from other physical sunscreen agents. [ABSTRACT FROM AUTHOR]

In order to elucidate the substantial effect and underlying mechanism of endogenous collagen on the texture development of fish balls, the structural and gelling properties of eel muscle collagen (EMC) under different heat treatments, as well as their effects on texture of eel ball, were investigated. EMC resulted in significant improvement of eel ball texture via gelling ability, filler effect, and interaction with starch. Under mild heating below 90°C for 30 min, the structural and physicochemical changes of EMC varied gradually, resulting in improved storage modulus of starch‐containing myofibrillar gel, a mimic of eel ball. However, overheating (100°C, 30 min) induced EMC degradation and significantly decreased the gel formation and the improvements in textural properties. Supplementation of EMC to eel balls significantly improved its gel strength, springiness, cohesiveness, and chewiness, as well as uniformity and tightness of the microstructure. These results suggest the texture development of eel ball can be regulated by heat‐induced structural changes, as well as structure–function relationship of collagen, compared with previous studies on myofibrillar proteins and exogenous gelatin; and they may provide texture‐related insights to the quality control of fish balls and diverse heat‐treated products of surimi containing collagen. [ABSTRACT FROM AUTHOR]

This paper firstly reported the preparation Chinese steamed bread with good water-binding capacity, emulsibility, organoleptic quality and nutrition by adding shortening and soybean meal into flour during the steamed bread-making process. The water-binding capacity, emulsibility and sensory score were selected as the indexes, single factor experiment and orthogonal experiment of shortening and soybean meal had been taken out. The result of orthogonal experiment shows that the best compound additive amount of water, soybean meal and shortening are 47.1, 3 and 2%, respectively. Calculation shows that the water-binding capacity of steamed bread increased by 80%; the emulsibility of the steamed bread increased by 65% and the sensory score of the steamed bread increased by 36%. The defect of lack of lysine in the traditional steamed bread can be efficiently improved. Steamed bread with more nutrition, better organoleptic quality and a longer shelf life was produced. The study is of significance in Chinese steamed bread and western bread-making process. Practical Applications Steamed bread with more nutrition, better organoleptic quality and a longer shelf life was produced. The study is of significance in Chinese steamed bread and western bread-making process. [ABSTRACT FROM AUTHOR]

Abstract: A novel lysozyme was isolated from the Canadian cranberry beans (Phaseolus vulgaris) and its enzymatic properties, antifungal and antibacterial activities were investigated. The isolation procedure involved aqueous extraction, ammonium sulfate precipitation, and chromatography purification including affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-Sephadex, and high performance liquid chromatography (HPLC) on Mono S. The enzyme exhibited a molecular mass of 15.6kDa in SDS-polyacrylamide gel electrophoresis both under reducing and non-reducing conditions, indicating that it was a monomeric protein. The 15N-terminal amino acid sequences were determined to be KVDMPGRFALAMQSH, showing some homology to hen egg white lysozyme. The pI was determined to be 9.6 by isoelectric focusing electrophoresis. The specific activity of the lysozyme was 652U/mg at pH 5.5 and 40°C. The lysozyme exhibited a pH optimum at pH 5.5 and a temperature optimum at 50°C. It exerted a potent inhibitory action toward fungal species including Alternaria alternata(Fr.) Keissl, Pythium aphanidermatum, Fusarium oxysporum and Botrytis cinerea, in addition to an antibacterial action against Staphylococcus aureus. However, it showed no effect on Gram-negative bacteria. The enzyme was thermostable below 58°C in both enzymatic reaction and antifungal activity. The present findings further the research on leguminous lysozyme with potentially exploitable significance. [Copyright &y& Elsevier]

ABSTRACT Plants have been one of the hot research topics in the search for potent antifungals. The objective of this study was to isolate a novel antifungal protein from Phaseolus limensis . A protein designated Limlin , with both antifungal and antibacterial activity was isolated and characterized. The isolation procedure entailed extraction, precipitation, affinity chromatography on Affi - gel blue gel, ion chromatography on SP-Toyopearl and gel filtration on Sephadex G-75. The protein exhibited a molecular mass of 34 kDa in SDS-polyacrylamide gel electrophoresis both under reducing and non-reducing conditions. Its N-terminal sequence was determined as QNNPAGFKGDKANAMLKMGNLSFQT, showing some homology to peroxidases and peroxidase precursors from plants. It potently suppressed mycelial growth of Fusarium solani , Mycosphaerella arachidicola and Pythium aphanidermatum . Moreover, this novel protein showed antiproliferative activity towards human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. This investigation first demonstrates an antifungal peroxidase with antiproliferative activity in large lima legume. PRACTICAL APPLICATIONS Plants are an important and indispensable part of life. Plants have evolved a variety of potent defense mechanisms because they are exposed to a large number of pathogenic organisms. They synthesize proteins and peptides that have antifungal activity. As their names imply, antifungal proteins and peptides serve a protective function against fungal invasion and play an important role in the defense of crops against fungal attack, thus diminishing serious economic losses. In this study, it is the first that demonstrates an antifungal peroxidase in large lima beans. The newly purified antifungal protein Limlin manifests antifungal, antibacterial activity and antiproliferative activity toward tumor cells. The aforementioned activities shown by peroxidase, provide further evidence for the potential significance in both medicine and agriculture. [ABSTRACT FROM AUTHOR]

Using plant-derived proteins as delivery materials to encapsulate lipophilic bioactive compounds is of great interest. Three protein fractions from brewers' spent grain (BSG) were extracted by the alkaline or alcoholic method with different procedures, and their potential to encapsulate curcumin was evaluated by preparing composite nanoparticles stabilized by lecithin using a pH-cycle method. The three protein fractions showed considerably different encapsulation properties. The particle size and entrapment efficiency varied from 173 to 306 nm and 21.2% to 83.9%, respectively. Compared with the other two fractions, the one extracted with 55% (v/v) ethanol showed better encapsulation performance. Curcumin after encapsulation exhibited an enhanced UV light and thermal stability while its antioxidant activity maintained. These results suggested that BSG protein could be a promising delivery material to encapsulate the water-insoluble bioactive compounds. • Protein fractions were extracted from brewers' spent grain (BSG) by alkaline or alcoholic methods. • Composite nanoparticles were prepared using BSG protein fractions to encapsulate curcumin. • BSG protein fraction obtained by 55% (v/v) ethanol showed better encapsulation performance. • BSG protein improved the UV light and thermal stability of curcumin without receding antioxidant activity. [ABSTRACT FROM AUTHOR]

Abstract: The Chinese bamboo leaf odorous frog (Rana (Odorrana) versabilis) and the North American pickerel frog (Rana palustris) occupy different ecological niches on two different continents with no overlap in geographical distribution. R. palustris skin secretions contain a formidable array of antimicrobial peptides including homologs of brevinin-1, esculentin-1, esculentin-2, ranatuerin-2, a temporin and a family of peptides considered of unique structural attributes when isolated, palustrins 1–3. Here we describe the structures of mature peptides and precursors of eight putative antimicrobial peptides from the skin secretion of the Chinese bamboo leaf odorous frog (Rana (Odorrana) versabilis). Each peptide represents a structural homolog of respective peptide families isolated from R. palustris, including two peptides identical in primary structure to palustrin 1c and palustrin 3b. Additionally, two peptides were found to be structural homologs of ranatuerin 2B and ranatuerin 2P from the closely-related North American species, Rana berlandieri (the Rio Grande leopard frog) and Rana pipiens (the Northern leopard frog), respectively. Both palustrins and ranatuerins have hitherto been considered unique to North American ranid frogs. The use of primary structures of amphibian skin antimicrobial peptides is thus questionable as a taxonomic device or alternatively, the micro-evolution and/or ancestry of ranid frogs is more highly complex than previously thought. [Copyright &y& Elsevier]

Corn fiber gum (CFG) belongs to a class of soluble, highly branched arabinoxylans derived from corn fiber. It can be isolated from deoiled and destarched corn fiber by mild-alkaline hydrogen peroxide treatments. This polysaccharide contains a small percentage of proteins, lipids, and nutraceutical phenolic compounds in the backbone. CFG has presented various practical applications in the food industry. It shows potential as an emulsifier for oil-in-water emulsion systems, whose emulsifying property is mostly related to the hydrophobic proteins and lipids bound to the carbohydrate moiety in CFG. CFG also exhibits unique biological activities , such as antioxidative activity, fermentability and immunomodulatory property, due to the nutraceutical phenolic compounds in CFG chains. This review summarizes recent findings on the isolation, physicochemical properties, biological activities, and functional properties of CFG. First, the review opens with a sketch of the extraction process of CFG from corn fiber. Then, the physicochemical properties and biological activities of CFG are comprehensively discussed. Thereafter, the current and potential applications of CFG in the food industry are introduced in detail. Finally, state-of-the-art approaches for improving the functional properties of CFG, especially its emulsifying property, are highlighted. Corn fiber gum exhibits different biological activities and functional properties, which are highly dependent on the extraction method. The biological activities and functional properties of CFG are closely related to its fine structural features , such as its molecular weight, protein content, and nutraceutical phenolic compound content. The bound ferulic acid contributes to CFG antioxidative activity. The emulsifying property of CFG is highly dependent on the protein content in the main backbone. However, the insufficient protein content in CFG chains limits the adoption of CFG as an emulsifier. Thus, the chemical or physical modification of CFG may boost its functional properties or endow it with new technologically important features. Overall, CFG has great potential use in the food industry as an antioxidant, immunomodulator, dietary fiber, and emulsifier. [Display omitted] • The structural features of CFG from different extraction methods are summarized. • Antioxidative and immunomodulatory activities, fermentability of CFG are reviewed. • Emulsifying and thickening properties of CFG are emphasized. • Overview of methods involved in improvement of functionality of CFG is provided. • Perspectives on current challenges and future research trends of CFG are presented. [ABSTRACT FROM AUTHOR]

Licorice was widely used in food and herbal medicine. In its extract industry, a substantial amount of licorice protein was produced and discarded as waste. Herein, we extracted Licorice Protein Isolate (LPI) and explored its potential as a curcumin nanocarrier. Using a pH-driven method, we fabricated LPI-curcumin nanoparticles with diameters ranging from 129.30 ± 3.21 nm to 75.03 ± 1.19 nm, depending on the LPI/curcumin molar ratio. The formation of LPI-curcumin nanoparticles was primarily driven by hydrophobic interactions, with curcumin entrapped in LPI being in an amorphous form. These nanoparticles significantly enhanced curcumin properties in terms of solubility, photochemical stability, and stability under varying pH, storage, and physiological conditions. Moreover, the loaded curcumin exhibited a 2.58-fold increase in cellular antioxidant activity on RAW 264.7 cells and a 1.86-fold increase in antitumor activity against HepG2 cells compared to its free form. These findings suggested that LPI could potentially serve as a promising novel delivery material. [ABSTRACT FROM AUTHOR]

Licorice was widely used in food and herbal medicine. In its extract industry, a substantial amount of licorice protein was produced and discarded as waste. Herein, we extracted Licorice Protein Isolate (LPI) and explored its potential as a curcumin nanocarrier. Using a pH-driven method, we fabricated LPI-curcumin nanoparticles with diameters ranging from 129.30 ± 3.21 nm to 75.03 ± 1.19 nm, depending on the LPI/curcumin molar ratio. The formation of LPI-curcumin nanoparticles was primarily driven by hydrophobic interactions, with curcumin entrapped in LPI being in an amorphous form. These nanoparticles significantly enhanced curcumin properties in terms of solubility, photochemical stability, and stability under varying pH, storage, and physiological conditions. Moreover, the loaded curcumin exhibited a 2.58-fold increase in cellular antioxidant activity on RAW 264.7 cells and a 1.86-fold increase in antitumor activity against HepG2 cells compared to its free form. These findings suggested that LPI could potentially serve as a promising novel delivery material. [ABSTRACT FROM AUTHOR]

From the aqueous extract of Semen Armeniacae Amarum , a major protein isolate was purified and characterized as a novel member of the 11S globulin family, which is composed of three polypeptides linked by disulfide bond. Furthermore, the feasibility of using the isolated protein for fabricating nanocarriers was investigated. The results indicate that thermal treatment of the globulin induced the rearrangement of the disulfide bond to form homodimers of acid polypeptides during the formation of nanoparticles. The harvested nanoparticles produced by heat-induced assembly are spherical in shape, with an average size of 92 nm and exhibited low cytotoxicity to L-02 and MDCK cell lines. These nanoparticles are capable to encapsulate paclitaxel, estimated the maximum encapsulation efficiency of paclitaxel loaded to the nanoparticles was 92.6% and the maximum release of paclitaxel was 57.4%. This research suggests that the screening of traditional herbal extracts could provide a novel source of protein nanocarriers. Unlabelled Image • A major protein SAP from Semen Armeniacae Amarum was purified and characterized as a novel member of the 11S globulin family. • The nanoparticles were fabricated by thermal treatment of SAP and exhibited low cytotoxicity to L-02 and MDCK cell lines. • Thermal treatment of SAP induced the rearrangement of the disulfide bond to form homodimers of acid polypeptides. • Paclitaxel was successfully encapsulated in the thermal assembled nanoparticles. [ABSTRACT FROM AUTHOR]

Bioactives can impact food function either by their dosage or by their forms of dispersion, though the latter remains mostly neglected. Here we report the incidental nanoparticles (iNPs) carrying hepatoprotective bioactives identified in freshwater clam (Corbicula fluminea Muller) soup, which is a folk remedy for liver conditions in East Asia. The soup was fractionated into two iNPs containing fractions with high yield (95.8%) in 35 min by gel chromatography. With hydrodynamic diameter (D h) range from 40 nm to 149 nm, iNPs were mainly constituted by carbohydrates and proteins. Notably, the majority of bioactives, e.g. taurine (63.2%), ornithine (68.1%) and phytosterols (60.0%), was determined to be carried by the iNPs. It suggested a possible mechanism of elevated delivery and absorption of bioactives, explaining why the clam soup can work at the bioactive concentrations way lower than the individual compound. These iNPs have great potential to be developed into a functional food with most potent nutraceutical effects. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Catalase-induced vigorous superoxide production in fish oil nano-emulsion. • The resulting superoxide caused fatal oxidative damages in murine macrophage. • The fish oil induced cell death can be inhibited by a catalase-specific inhibitor. • The cell death involves ferroptosis but not apoptosis. • A hidden health risk of the fish oil nano-emulsion was discovered. Fish oil is increasingly utilised in the form of nano-emulsion as a nutrient and function fortifier. The nano-emulsions exceptionally high content of polyunsaturated fatty acids and electron donors at the oil/water interface provide an ideal site of the redox reaction. Here we report that a vigorous superoxide production in the fish oil nano-emulsion was catalysed by mammalian catalase in acellular and cellular systems. The resulting superoxide increased cytosolic reactive oxygen species (ROS) and membrane lipid peroxidation of murine macrophage, which eventually causes fatal oxidative damages. Cell death, was significantly inhibited by a catalase-specific inhibitor 3-Amino-1,2,4-triazole (3-AT), was via ferroptosis and not apoptosis. The ferroptosis was independent of free iron or glutathione peroxidase suppression. Our findings discovered a hidden health risk of the widely acclaimed fish oil emulsion, suggesting a novel cellular damage mechanism caused by dietary unsaturated fats on the alimentary tract mucosa. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether the cellular uptake of cargo proteins can be enhanced by fusing a Tat peptide in the center of proteins; glutathione-S-transferase (GST)-Tat-green fluorescent protein (GFP) and GST-GFP-Tat proteins were first constructed and expressed. The cellular internalization of both proteins was then evaluated and compared in HeLa cells using fluorescent microscopy and flow cytometry, as well as the transdermal delivery in human skin using confocal microscopy. Results from in vitro cell experiments showed that GST-Tat-GFP protein efficiently internalized into HeLa cells when a Tat peptide was fused in the center of proteins, whereas its efficiency is lower than that of GST-GFP-Tat protein with a Tat peptide terminal fused. Ex vivo transdermal delivery data also demonstrated that the lower efficiency of GST-Tat-GFP penetrating through human stratum corneum layer when compared with GST-GFP-Tat. Furthermore, both GST-GFP-Tat and GST-Tat-GFP presented a various degree of a mixture of cytoplasmic diffuse staining and punctate surface staining, and the pattern of distribution varied considerably in HeLa cell experiments depending on the concentration of protein used. Therefore, an improved mechanism for Tat-conjugated proteins was proposed, in which Tat-conjugated proteins were first associated with cell membrane, then accumulated on the cell surface, and finally internalized into cells by pore formation mechanism. [ABSTRACT FROM AUTHOR]

Emulsions are thermodynamically unstable systems that tend to separate into two immiscible phases over time. The interfacial layer formed by the emulsifiers adsorbed at the oil-water interface plays an important role in the emulsion stability. The interfacial layer properties of emulsion droplets have been considered the cutting-in points that influence emulsion stability, a traditional motif of physical chemistry and colloid chemistry of particular significance in relation to the food science and technology sector. Although many attempts have shown that high interfacial viscoelasticity may contribute to long-term emulsion stability, a universal relationship for all cases between the interfacial layer features at the microscopic scale and the bulk physical stability of the emulsion at the macroscopic scale remains to be established. Not only that, but integrating the cognition from different scales of emulsions and establishing a unified single model to fill the gap in awareness between scales also remain challenging. In this review, we present a comprehensive overview of recent progress in the general science of emulsion stability with a peculiar focus on interfacial layer characteristics in relation to the formation and stabilization of food emulsions, where the natural origin and edible safety of emulsifiers and stabilizers are highly requested. This review begins with a general overview of the construction and destruction of interfacial layers in emulsions to highlight the most important physicochemical characteristics of interfacial layers (formation kinetics, surface load, interactions among adsorbed emulsifiers, thickness and structure, and shear and dilatational rheology), and their roles in controlling emulsion stability. Subsequently, the structural effects of a series of typically dietary emulsifiers (small-molecule surfactants,proteins, polysaccharides, protein–polysaccharide complexes, and particles) on oil–water interfaces in food emulsions are emphasized. Finally, the main protocols developed for modifying the structural characteristics of adsorbed emulsifiers at multiple scales and improving the stability of emulsions are highlighted. Overall, this paper aims to comprehensively study the literature findings in the past decade and find out the commonality of multi-scale structures of emulsifiers, so as to deeply understand the common characteristics and emulsification stability behaviour of adsorption emulsifiers with different interfacial layer structures. It is difficult to say that there has been significant progress in the underlying principles and technologies in the general science of emulsion stability over the last decade or two. However, the correlation between interfacial layer properties and physical stability of food emulsions promotes revealing the role of interfacial rheological properties in emulsion stability, providing guidance on controlling the bulk properties by tuning the interfacial layer functionality. [Display omitted] • Insight into fundamentals of the interfacial properties of food emulsions at multiple scales. • Diversity of the interfacial properties induced by various types of food emulsifiers. • Critical roles of the interfacial properties on regulating emulsion stability. • Comprehensive delineation of recent progress on the correlation between interfacial properties and emulsion stability. • Perspectives on the challenges and future road map for drawing conclusions of this correlation. [ABSTRACT FROM AUTHOR]

The antidiabetic effects of Ge-Gen-Qin-Lian-Tang decoction (GQD) have been proven clinically. In a pharmacological study conducted on STZ-induced diabetic rats, the constitutive aggregates/sediments of Ge-Gen-Qin-Lian-Tang decoction exhibited stronger hypoglycemic and antioxidant activities compared to the soluble compositions. This study aims to demonstrate the pharmacological properties of aggregates derived from GQD by measuring permeability of the active monomer phytochemicals (e.g., baicalin) in a Caco-2 cell monolayer and determine the cellular viability, intracellular redox status (MDA and SOD), and insulin secretion of pancreatic β-cell line, INS-1, following STZ-induced oxidative stress. The aggregates were separated into three fractions, namely, “MA (microaggregates),” “400 g supernatant,” and “MNA (micro-/nanoaggregates),” by centrifugation at 400 ×g and 15000 ×g, respectively. Aggregates in the sediment increased baicalin absorption, showed little toxicity to β-cells, elevated intracellular SOD levels, and significantly suppressed oxidative damage effects on cellular viability and functions. The “MA” fraction had a larger particle size and provided higher antioxidant cellular protection than “MNA” in vitro, implying that the sediments may be the active components in the herbal decoction. The actions of these micro-/nanoaggregates may provide a new perspective for understanding the antidiabetic effects of herbal decoctions and aid in interpretation of synergistic actions between the multiple components. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the interactions between TAT peptides and a neutral DOPC bilayer by using neutron lamellar diffraction. The distribution of TAT peptides and the perturbation of water distribution across the DOPC bilayer were revealed. When compared to our previous study on an anionic DOPC/DOPS bilayer (X. Chen et al., Biochim Biophys Acta. 2013. 1828 (8), 1982–1988), a much deeper insertion of TAT peptides was found in the hydrophobic core of DOPC bilayer at a depth of 6.0 Å from the center of the bilayer, a position close to the double bond of fatty acyl chain. We conclude that the electrostatic attractions between the positively charged TAT peptides and the negatively charged headgroups of phospholipid are not essential for the direct translocation. Furthermore, the interactions of TAT peptides with the DOPC bilayer were found to vary in a concentration-dependent manner. A limited number of peptides first associate with the phosphate moieties on the lipid headgroups by using the guanidinium ions pairing. Then the energetically favorable water defect structures are adopted to maintain the arginine residues hydrated by drawing water molecules and lipid headgroups into the bilayer core. Such bilayer deformations consequently lead to the deep intercalation of TAT peptides into the bilayer core. Once a threshold concentration of TAT peptide in the bilayer is reached, a significant rearrangement of bilayer will happen and steady-state water pores will form. [ABSTRACT FROM AUTHOR]

A novel lectin with a molecular mass of 24.3 kDa, designated Lunatin , was isolated from edible seeds of Phaseolus lunatus billb . The purification scheme consisted of ammonium sulfate precipitation, affinity chromatography, ion exchange chromatography, and gel filtration chromatography. The lectin is a glycoprotein, as determined by staining with periodic acid-Schiff (PAS), and its N-terminal amino acid sequence was determined to be DAVIYRGPGDLHTGS. Lunatin exhibited hemagglutinating activity towards human blood group A erythrocytes, which was mostly preserved up to 50 °C and retained at ambient temperature at pH 2.0–11.0. d -fructose, d -galactose, d -glucose, and mannitol were capable of inhibiting its hemagglutinating activity. Lunatin was found to be a metal-dependent protein, as its activity was inhibited by the metallic compounds K 2 Cr 2 O 7 , SnCl 2 , and LiCl, though it was unaffected by MgCl 2 , ZnCl 2 , BaCl 2 , CuCl 2 , FeCl 3 , or CaCl 2 . In addition, Lunatin exerted potent antifungal activity toward a variety of fungal species, including Sclerotium rolfsii, Physalospora piricola, Fusarium oxysporum, and Botrytis cinerea. Finally, proliferation of K562 leukemia cells was strongly inhibited by Lunatin , with an IC 50 of 13.7 μM, whereas HeLa and HepG2 cells were only weakly affected. These findings further the identification and understanding of functional factors in edible plant seeds. [ABSTRACT FROM AUTHOR]

• HCQ statically quenching the fluorescence of CAS and WP. • Hydrophobic interactions and hydrogen bonds are the forces for complexes formation. • The four major proteins in milk exhibited different binding sites with HCQ. • The complex of HCQ-CAS was more stable compared to HCQ-WP. This study investigated the interaction between hydroxychloroquine sulfate (HCQ) and caseins (CAS) or whey proteins (WP) by the means of various spectroscopic, molecular docking, and molecular dynamic (MD) simulation. The fluorescence spectrum revealed that CAS and WP interaction with HCQ resulted in static quenching due to the formation of HCQ-CAS and HCQ-WP complexes. The formation of complexes was also validated by fourier transform infrared spectroscopy (FTIR), circular dichroism spectroscopy (CD), X-ray diffraction (XRD), and scanning electron microscope (SEM). The FTIR and CD data revealed that HCQ binding altered the secondary structure of CAS and WP. Moreover, molecular docking and MD simulation were performed to analyze the formation of complexes, which compacted the CAS structure. Moreover, they also demonstrated that HCQ interaction with CAS and WP mainly involved hydrophobic interactions, with some hydrogen bonding and electrostatic attraction forces. This was consistent with the zeta potential, thermodynamic and FTIR analyses. In conclusion, the present study guides the construction of the CAS and WP as a drug delivery system for HCQ and helps us understand how HCQ interacts with food components such as milk proteins. [ABSTRACT FROM AUTHOR]

The metal ions play a decisive role in regulating the redox balance of cells and subsequentially alter cellular functions. The pacifying ("cold") or irritating ("hot") effects of food on the human body have been traditionally recognized and utilized by Chinese for hundreds of years. The principal components of fruits and vegetables corresponding to these effects have been identified to be magnesium, iron, and copper cations in combination. This study aims to elucidate the regulatory effects of the three cations on the oxidative responses and inflammatory cytokines production in RAW264.7 macrophages. Two "cold" solutions and two "hot" solutions were prepared with MgSO 4 , FeSO 4 , and CuSO 4. The contents of three cations were calculated with a previously established regression equation and set to the physiologically meaningful levels (at ppm). It was found that the "cold" solution exhibited antioxidant and anti-inflammatory effects in the macrophages. They reduced the intracellular ROS level and restored the mitochondrial respiratory of the AAPH-insulted macrophages, while suppressing the LPS-induced expression of TNF-α, IL-1β, and IL-6 in the cells. Conversely, the "hot" solutions exhibited pro-oxidative and pro-inflammatory effects as they increased the intracellular ROS and expression of inflammatory cytokines in normal cells. It demonstrates the bidirectional regulation of the Mg2+, Cu2+, and Fe2+ cocktails on oxidative and inflammatory responses of murine macrophages. Inspired by the traditional Chinese food concept, the outcome of this study provides a new perspective and useful tool for future research and innovations in healthy and sustainable food. • The Mg2+, Cu2+, and Fe2+ cocktails could bidirectionally regulate the macrophages. • The "cold" mineral solutions exhibited antioxidative and anti-inflammatory activity. • The "hot" mineral solutions possessed pro-oxidative and pro-inflammatory activity. [ABSTRACT FROM AUTHOR]

A tripeptide peptide with strong calcium-binding capacity was isolated and purified from whey protein hydrolysates using diethylaminoethyl cellulose anion-exchange chromatography, Sephadex G-25 gel filtration, semi-preparative reversed-phase (RP) high-performance liquid chromatography (HPLC) and analytical HPLC. It was identified using liquid chromatography-electrospray ionisation mass spectrometry and shown to have a molecular mass of 396.98 Da with the confirmed amino acid sequence Tyr-Asp-Thr. The calcium-binding capacity of Tyr-Asp-Thr reached 79.5 μg mg −1 , an increase of 134% compared with the unpurified hydrolysate complex. The characteristics of the Tyr-Asp-Thr-Ca chelate were investigated, indicating that the major binding sites included oxygen atom of the carbonyl group and nitrogen of amino group or imino group; structural modifications of the peptide arose with the addition of calcium ion. The findings suggest the potential of peptide-calcium chelates as dietary supplements. [ABSTRACT FROM AUTHOR]

A trypsin inhibitor with thermal and pH stability, designated M ercine, was prepared from seeds of G lycine max ( L .) merr. The preparation procedure involved ammonium sulfate precipitation, ion-exchange chromatography on CM- Sephadex C-50, affinity chromatography on Affi-gel blue gel. The 20 N-terminal amino acid sequences were determined to be DEYSKPCCDLCMCTRRMPPQ, demonstrating highly homologies with the sequence of Bowman- Birk type trypsin inhibitors. The molecular mass and isoelectric point of the inhibitor were estimated by SDS- PAGE and isoelectric focusing to be 17.9 kD and 4.6, respectively. Trypsin could be completely inhibited by M ercine when the molar ratio was 8.0. The inhibitory activity of M ercine was unaffected after exposure to temperatures up to 80C, or within the pH range 2-12. Besides inhibiting trypsin-chymotrypsin, the inhibitor M ercine demonstrated additional antifungal activity toward the species of A lternaria alternate, F usarium oxysporum, P ythium aphanidermatum, P hysalospora piricola and B otrytis cinerea. Practical Applications We here report, for the first time, not only the trypsin inhibitor's preparation, but also its N-terminal amino acid sequence and antifungal activity against a series of phytopathogenic fungi. The aforementioned activities shown by trypsin inhibitor, provide further evidence for the potential significance in agriculture. [ABSTRACT FROM AUTHOR]

A novel trypsin inhibitor with thermal and pH stability, designated Merrtine, was isolated from Glycine max L. merr. The procedure involved ammonium sulfate precipitation, ion-exchange chromatography on CM-Sephadex C-50, and affinity chromatography on Affi-gel blue gel. The 20 N-terminal amino acid sequences were determined to be DEYSKPCCDLCMCTRRCPPQ, demonstrating high homology with the sequence of Bowman–Birk type trypsin inhibitors. The molecular mass and isoelectric point of the inhibitor were estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and isoelectric focusing to be 20.0 kD and 5.8, respectively. Trypsin could be completely inhibited by Merrtine when the molar ratio was 8.1. The inhibitory activity of Merrtine was unaffected after exposure to temperatures up to 85°C, as well as within the pH range 2–12. Besides inhibiting trypsin–chymotrypsin, the inhibitor demonstrated additional antifungal activity against the species of Alternaria alternate, Fusarium oxysporum, Pythium aphanidermatum, Physalospora piricola, Botrytis cinerea, and Fusarium solani. We herein report not only the trypsin inhibitor's extraction and isolation for the first time, but also its physiochemical and antifungal properties. [ABSTRACT FROM AUTHOR]

Tea infusion is a colloidal system. As a first attempt to systematically characterize tea micro-nanoparticles, the effect of pH on colloidal properties of Lapsang souchong black tea infusion was investigated in this study. At the native pH 5 of black tea infusion, micro/nanoparticles were revealed by Cryo-TEM (Cryo-transmission electron microscopy) to be of a structure consisting of dominantly spherical polyphenol oxidase (PPO)-polyphenols complexes and surrounding linear polysaccharide chains with an average hydrodynamic diameter (D h) of 128 nm and ζ-potential of −23.7 mV. It is the first time to demonstrate the black tea micelle consists of spherical and fibrous nanostructures, possibly responding to protein and polysaccharides. Increasing pH resulted in a decrease in polyphenols content and the disassembling of the micro/nanostructure. On the other hand, the decrease of pH through their respective isoelectric points led to the formation of PPO-polyphenols complexes, polysaccharide aggregation, and further aggregations among different molecules and their complexes and a drastic increase in the precipitation when pH was lower than pH 5. The predominant effect of pH on colloidal properties of black tea infusion reveals an electrostatic nature of intramolecular and intermolecular interactions among PPO, polysaccharides and polyphenols. Those results provide new clues to a practical and effective quality control of black tea products as well as an insight into health benefits of black tea. • The black tea contains negatively charged NPs (Dh = 128 nm) at its native pH of 5. • Increasing pH induced the disassembly of the micro/nanostructure. • pH < 5, formation of complexes and precipitates was promoted. • Electrostatic interaction primarily defines the nanostructure. [ABSTRACT FROM AUTHOR]

Abstract: Almonds and almond skins are rich in fiber and other components that have potential prebiotic properties. In this study we investigated the prebiotic effects of almond and almond skin intake in healthy humans. A total of 48 healthy adult volunteers consumed a daily dose of roasted almonds (56 g), almond skins (10 g), or commercial fructooligosaccharides (8 g) (as positive control) for 6 weeks. Fecal samples were collected at defined time points and analyzed for microbiota composition and selected indicators of microbial activity. Different strains of intestinal bacteria had varying degrees of growth sensitivity to almonds or almond skins. Significant increases in the populations of Bifidobacterium spp. and Lactobacillus spp. were observed in fecal samples as a consequence of almond or almond skin supplementation. However, the populations of Escherichia coli did not change significantly, while the growth of the pathogen Clostridum perfringens was significantly repressed. Modification of the intestinal microbiota composition induced changes in bacterial enzyme activities, specifically a significant increase in fecal β-galactosidase activity and decreases in fecal β-glucuronidase, nitroreductase and azoreductase activities. Our observations suggest that almond and almond skin ingestion may lead to an improvement in the intestinal microbiota profile and a modification of the intestinal bacterial activities, which would induce the promotion of health beneficial factors and the inhibition of harmful factors. Thus we believe that almonds and almond skins possess potential prebiotic properties. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: The herbal decoction is a complex dispersion system containing solutes, colloid, aggregates, emulsions and precipitates. In which phase bioactive phytochemicals are dispersed determines their delivery, action and metabolism. This study took ephedrine, a well-studied and widely used phytochemical, as an example to elucidate its exact distribution in the phases of Ma-Xing-Shi-Gan-Tang decoction (MXSGT), which is an Ephedra sinica Stapf. containing traditional Chinese medicinal formula, and the biological meaning of this distribution correspondingly. It may provide an important update to the safety and efficacy assessment of the herbal decoction and its active phytochemicals. Materials and methods: In this study, the decoction was fractionated with size-exclusion chromatography coupled with multi-angle laser light scattering detector. The morphology of fractionated nanoparticles was observed with AFM and SEM. The bioactivities of the decoction, the ephedrine alkaloids loaded NPs (prepared by chromatography isolation) and the synthetic ephedrine were assessed by cell proliferation tests using five cell lines, namely Caco-2, L-02, Hep-G2, NR-8383, and Hela-229. Results: Nanoparticles with radii of gyration ranged from 50 to 150nm were isolated, in spherical shape. Further analysis of nanoparticles on the subsequent reversed phase chromatography revealed that the majority of ephedrine (99.7%) and pseudoephedrine (95.5%) were associated with these nanoparticles, rather than dispersed freely in the real solution. The addition of both the herbal decoction and the separated ephedrine-loaded nanoparticles reserved higher cell viability/proliferation than that of the sole synthetic ephedrine among the Caco-2, L-02, Hep-G2, and NR-8383 cells. In contrast, the nanoparticles reduced the proliferating power of ephedrine on Hela-229 cells. In general, the ephedrine-loaded NPs conducted the intermediate influences on the cell viability, in either way. Conclusions: The colloidal nanoparticles were separated from the decoction. The association of ephedrine alkaloids with nanoparticles was demonstrated and may have changed the bioactivity of the alkaloids. The naturally occurred colloidal nanoparticles may play an important role in the pharmacological properties of both the decoction and its active phytochemicals, therefore warrant further studies. [Copyright &y& Elsevier]

In this study, the potential use of donkey serum albumin ( DkSA) hydrolysates prepared by tryptic hydrolysis as cancer inhibitor was investigated. DkSA was isolated and purified from donkey plasma by anion-exchange chromatography on Source 15 Q. The DkSA hydrolyzed by trypsin was ultrafiltrated using ultrafiltration membrane with a molecular weight cut-off of 1 kDa to obtain peptides mixture ( HPM). The HPM showed inhibitory effect on the proliferation of different cancer cells, including human leukemia HL-60 cells, liver hepatoma HepG2 cells and breast cancer MDA-MB-231 cells under different concentrations. One of the most effective inhibitions was observed toward leukemia HL-60 cells with a 50% inhibitory concentration ( IC50) of 0.073 mg/ mL. Further experiments confirmed that the HPM induced leukemia cell apoptosis, which was observed by transmission electron microscope. However, the HPM had no significant effect on cell cycle distribution. This study suggests that the peptides derived from DkSA could inhibit tumor cell proliferation. Practical Applications Enzymatic degradation products of proteins have multiple functions and the hydrolysates have been applied to produce a variety of functional foods, especially in the application of plant protein hydrolysates. Recently, the application of animal protein hydrolysates is gradually developed, in particular, to be used to inhibit cancer cell proliferation. This study revealed for the first time that hydrolysates of donkey serum albumin by trypsin had a relatively high inhibiting capability in tumor cell proliferation. It was much more effective in inhibiting leukemia cells than inhibiting liver cancer cells and breast cancer cells. The effect suggested that the peptides derived from donkey serum albumin could be functional food for anticancer in the future. [ABSTRACT FROM AUTHOR]

A novel trypsin inhibitor with considerable thermal and pH stability, designated Glytine, was isolated from seeds of the Chinese black soybean Glycine max (L.) Merr. The purification procedure involved ammonium sulfate precipitation, ion-exchange chromatography on CM-Sephadex C-50, gel filtration chromatography on Sephacryl S-200HR, and gel filtration chromatography on POROS HS-20. The 20 N-terminal amino acid sequences were determined to be DEYSKPCCDLCMCTRRCPPQ, demonstrating close homology with the sequences of leguminous trypsin inhibitors. The molecular mass and isoelectric point of the inhibitor were estimated by SDS-PAGE and isoelectric focusing to be 19.9 kDa and 6.2, respectively. Trypsin could be completely inhibited by Glytine when the weight ratio was 1.5. The inhibitory activity of Glytine was unaffected by exposure to temperatures up to 100 °C, or within the pH range 2-12. Besides trypsin-chymotrypsin inhibition activity, Glytine demonstrated other biological activities including antiproliferative activity against tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. In addition, the inhibitor showed antifungal activity against Pythium aphanidermatum, Fusarium oxysporum, Alternaria alternata ( Fr.) Keiss, Fusarium solani, and Botrytis cinerea. This study extended research on leguminous trypsin-chymotrypsin inhibitor and suggested exploitable potential. [ABSTRACT FROM AUTHOR]

Abstract: TAT peptide is one of the best-characterized cell penetrating peptides derived from the transactivator of transcription protein from the human immunodeficiency virus 1. The aim of this study was to investigate the interaction between TAT peptide and partially negatively-charged phospholipid bilayer by using lamellar neutron diffraction. The main findings are the existence of a contiguous water channel across the bilayer in the presence of TAT peptide. Taken in combination with other observations, including thinning of the lipid bilayer, this unambiguously locates the peptide within the lipid bilayer. The interaction of TAT peptide with anionic lipid bilayer, composed of an 80:20 mixture of DOPC and DOPS, takes place at two locations. One is in the peripheral aqueous phase between adjacent bilayers and the second is below the glycerol backbone region of bilayer. A membrane thinning above a peptide concentration threshold (1mol%) was found, as was a contiguous transbilayer water channel at the highest peptide concentration (10mol%). This evidence leads to the suggestion that the toroidal pore model might be involved in the transmembrane of TAT peptide. We interpret the surface peptide distribution in the peripheral aqueous phase to be a massive exclusion of TAT peptide from its intrinsic location below the glycerol backbone region of the bilayer, due to the electrostatic attraction between the negatively-charged headgroups of phospholipids and the positively charged TAT peptides. Finally, we propose that the role that negatively-charged headgroups of DOPS lipids play in the transmembrane of TAT peptide is less important than previously thought. [Copyright &y& Elsevier]

Hydroxychloroquine sulfate (HCQ) is a well-established antimalarial drug that has received considerable attention during the COVID-19 associated pneumonia epidemic. Gelatin is a multifunctional biomacromolecule with pharmaceutical applications and can be used to deliver HCQ. The effect of HCQ on the gelation behaviors, water mobility, and structure of gelatin was investigated to understand the interaction between the drug and its delivery carrier. The gel strength, hardness, gelling (T g) and melting (T m) temperatures, gelation rate (k gel), and water mobility of gelatin decreased with increasing amounts of HCQ. The addition of HCQ led to hydrogen bonding that interfered with triple helix formation in gelatin. Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD) analysis further confirmed that the interaction between HCQ and gelatin is primarily through hydrogen bonding. Atomic force microscopy (AFM) revealed that higher content of HCQ resulted in more and larger aggregates in gelatin. These results provide not only an important understanding of gelatin for drug delivery design but also a basis for the studying interactions between a drug and its delivery carrier. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydroxychloroquine sulfate (HCQ) is a well-established antimalarial drug that has received considerable attention during the COVID-19 associated pneumonia epidemic. Gelatin is a multifunctional biomacromolecule with pharmaceutical applications and can be used to deliver HCQ. The effect of HCQ on the gelation behaviors, water mobility, and structure of gelatin was investigated to understand the interaction between the drug and its delivery carrier. The gel strength, hardness, gelling (T g) and melting (T m) temperatures, gelation rate (k gel), and water mobility of gelatin decreased with increasing amounts of HCQ. The addition of HCQ led to hydrogen bonding that interfered with triple helix formation in gelatin. Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD) analysis further confirmed that the interaction between HCQ and gelatin is primarily through hydrogen bonding. Atomic force microscopy (AFM) revealed that higher content of HCQ resulted in more and larger aggregates in gelatin. These results provide not only an important understanding of gelatin for drug delivery design but also a basis for the studying interactions between a drug and its delivery carrier. [Display omitted] [ABSTRACT FROM AUTHOR]

It has been revealed that numerous nanoparticles are formed during the boiling preparation of traditional Chinese medical decoctions and culinary soups. They may possess physiological effects different from those of constituent components and are worth paying attention to but are barely noticed and investigated as of yet. In this study, six groups of nanoparticles, whose size ranged from 57 to 300 nm, were successfully isolated from the decoction of Isatis indigotica Fort. root, according to their particle size by the means of size-exclusive chromatography. All of the obtained nanoparticles have a high content of polysaccharides, which distinguishes them from the disclosed BLG protein nanoparticles. They also have high similarities in other compositions, surface charge, and stimuli responses. However, four out of these six nanoparticles (F2, F3, F4, and F5) exhibited significant antiviral activity against influenza virus H1N1, and their antiviral activities and cytotoxicity towards MDCK cells varied with their sizes. It suggested that the antiviral efficacy of BLG decoction could also be from its nanoparticles besides its well-known antiviral phytochemicals. It also implied that the biological effects of these polysaccharide nanoparticles, including cytotoxicity and antiviral activity, may be correlative with the physicochemical properties, especially the particle size. [ABSTRACT FROM AUTHOR]

The objectives of this study were to identify the chemical composition, monosaccharide composition, and molecular weight (Mw) of the polysaccharide (LBP) extract from Lycium barbarum L., and investigate the effects of Ca2+ on the zeta potential, rheological properties, infrared spectra (IR), and structure as well as the gelation mechanism of the LBP. The results showed that the LBP was an acidic glycoprotein mixture with an Mw of 4.05 × 105 Da. The addition of Ca2+ first decreased and then increased the absolute value of zeta potential. The elastic modulus (G'), complex viscosity (η*), and stress relaxation modulus (G(t)) of LBP increased with an increase of Ca2+ concentration, and reached the maximum value at the concentration of 12 mM. IR showed that the typical peak wavenumber of the LBP has changed in the presence of Ca2+. SEM and AFM analysis confirmed that Ca2+ could improve the formation of gel network structure in LBP. In addition, the electrostatic interaction and the calcium bridges produced by the addition of Ca2+ played a key role in the formation of the gel network structure. These findings will benefit the application of LBP in the food and pharmaceutical industries. [Display omitted] • Effect of Ca2+ on the rheological properties and structure of LBP was investigated. • Gelation mechanism of LBP was also elucidated. • Increasing concentration of Ca2+ improved rheological properties of the LBP gels. • Ca2+ increased the stability of LBP gel network structure. • Electrostatic interaction was crucial to LBP gel network structure formation. [ABSTRACT FROM AUTHOR]

Maillard reaction can influence the functionalities of myofibrillar protein (MP). Protein-saccharide Maillard-type conjugates improve the solubility of MP but impair its thermal gelling ability. Besides, the influences of Maillard reaction occurred between reducing sugar and free amino acids on MP were not inspected yet. In this study, arginine-glucose Maillard reaction products (MRPs) were adopted to investigate their effects on the physicochemical and gel properties of chicken MP. The results showed that Arg-Glc MRPs significantly decreased surface hydrophobicity and the content of reactive sulfhydryl group, subsequently influenced the gelling behavior and gel properties, e.g., water holding capacity and gel strength. The dynamic rheological results revealed that MRPs reduced the storage modulus value effectively. Scanning electron microscopy showed that the three-dimensional network structure of MP gel became coarser and irregular by the treatment of Arg-Glc MRPs. These results suggested that Arg-Glc MRPs have influences on both the physicochemical properties and the gel properties of MP, which may provide new information to the effects of MRPs on the water holding capacity and texture of meat products. • MRPs lowered the gel strength and the G′ values of myofibrillar protein (MP). • Arg-Glc MRPs also reduced the surface hydrophobicity and reactive SH group content. • MP gels displayed a coarser and more irregular network by treating with the MRPs. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Antitumour effects of pentapeptide (LH) derived from donkey serum albumin hydrolysates were tested against tumour cells both in vitro and in vivo. The mechanism of LH induced tumour cell apoptosis was investigated. Main methods: Human promyelocytic leukaemia cells (HL 60) were cultured to observe inhibition in vitro. Two animal models, a solid tumour and a non-entity myeloid leukaemia tumour, were used to determine the effect of LH in vivo. The former, fifty BALB/c nude mice were transplanted with HL 60 cells. The tumours were isolated completely and weighed after treatment. The latter, fifty BALB/c mice were injected intravenously with transplantable erythroblastic leukaemia cells (EL9611 cells). The survival time of mice was recorded and organs were used for histological study. The mechanism about tumour cell apoptosis was evaluated using fluorescence-activated cell sorting and transmission electron microscope for morphological assays. Key findings: The LH inhibited tumour cell proliferation and the inhibitions were dependent on both the concentration and the dose; the best inhibition rate was up to 70% of the untreated control in vitro. It markedly inhibited the growth of a transplanted tumour with HL 60 cells in an immune-deficient nude mouse model. LH was also able to prolong the survival time of leukaemia mice with transplanted EL9611 cells and prevent the infiltration of leukaemia cells to the main internal organs. Significance: The LH peptide is an excellent inhibitor of tumour cell growth. These data provide the experimental foundation to use the LH peptide as a candidate for antitumour drugs in the future. [Copyright &y& Elsevier]

Abstract: Aims: Radiation-induced lung injury is one of the limiting factors for radiation therapy. SOD-TAT, a fusion protein of HIV-1 Tat protein transduction domain and hCuZn-superoxide dismutase (SOD), has been proved to be effective in preventing and treating the damage of the skin of guinea pigs by UVB radiation. In this study, we demonstrated SOD-TAT''s radioprotective effects on lung injury in irradiated mice. Main methods: SOD-TAT was purified from yeast culture with ion exchange chromatography. Kunming mice were randomly divided into three groups: a control group, a group injected with wild SOD and a group injected with SOD-TAT. Pulmonary SOD activity of mice was determined 4.5h after injection. C57BL/6 mice were randomly divided into four groups: a control group, an irradiation group, an irradiation group treated with amifostine 0.5h before the irradiation and an irradiation group treated with SOD-TAT 4.5h before irradiation. The monthly growth rate of every mouse''s weight was calculated and the level of hydroxyproline content and antioxidant activity in lung were determined 5months after irradiation. Key findings: SOD-TAT was transduced into the lung in vivo. SOD-TAT pretreatment could improve the growth rate of irradiated mice, significantly reduce the pulmonary hydroxyproline content, and maintain the SOD activity, glutathione peroxidase (GSH-Px) activity and total anti-oxidation capacity (T-AOC). Compared with amifostine, SOD-TAT was more effective in increasing the activities of pulmonary antioxidant enzymes. Significance: Compared with amifostine, SOD-TAT treatment more effectively enhanced pulmonary antioxidant ability, reduced radiation-induced pulmonary fibrosis and improved the living quality of irradiated mice. [Copyright &y& Elsevier]

Abstract: A superoxide dismutase (SOD) was purified from seeds of the Chinese black soybean(Glycine max cv). The purification procedure comprised ammonium sulfate precipitation, ion-exchange chromatography on CM-Sephadex C-50, affinity chromatography on Affi-gel blue gel and HP LC on DEAE 650-C. The final enzyme was purified 15.40 fold with a specific activity of 4619.3U/mg protein and a recovery of enzyme was 29.41% from (NH4)2SO4 precipitation. The SDS-PAGE of the purified protein exhibited a molecular mass of 31.0kDa and could be depolymerized spontaneously to a band at about 14.5kDa in non-reducing conditions, and a diffusion band at about 15.5kDa in reducing conditions, indicating a double-strand protein with intra-molecular disulfide bridges. The isoelectric point was determined to be 5.6, indicating it''s an acidic protein. The enzyme is a type of copper plus zinc superoxide dismutase (Cu, Zn-SOD) because it was greatly inhibited by hydrogen peroxide, insensitive to chloroform–ethanol, and the maximum ultraviolet absorbance was found to be 266nm. Thermostability experiments showed that the activity of the purified enzyme was stable after exposure to temperatures below 50°C, and the activity could be well maintained between pH 6.0 and 8.0. Moreover, the SOD exerted an obvious protective effect against oxidative stress of UVC radiation in normal human liver cell strain L-02 cells. [Copyright &y& Elsevier]

Abstract: A novel chitinase with antifungal activity was isolated from fava bean (Vicia faba) seeds. The protein exhibited a molecular mass of 21.5kDa in reduced condition while 25.5kDa in oxidized condition on SDS-PAGE, indicating that there are disulfide bonds inside the molecule. Its N-terminal amino acid sequence was determined to be D-D-V-G-S-V-I-S-A-S-L-F-E-Q-L-L-K-H, showing homologous to those of chitinase and chitinase precursors from leguminous plants. The optimum pH and the optimum temperature for activity toward N-acetyl-d-glucosamine were 5.4 and 50°C, respectively. The pI was determined to be 8.7 by isoelectric focusing electrophoresis. The chitinase was thermostable up to 58°C in both enzymatic reaction and antifungal activity. It showed chitin-binding activity, suggesting that the catalytic domain is involved in the binding of chitinase to a certain extent. In addition, it exerted potent antifungal action toward a variety of fungal species including Pythium aphanidermatum, Fusarium solani, Physalospora piricola, Alternaria alternate, Botrytis cinerea, and Fusarium oxysporum f. sp. melonis. The present findings demonstrated a novel chitinase with disulfide bonds inside the molecule and show antifungal significance in agriculture. [Copyright &y& Elsevier]

Abstract: TAT-SOD is a recombinant protein of superoxide dismutase fused with TAT peptide. By pure accident, we discovered that topical application of TAT-SOD to acupoints could result in acupuncture-like action. This study aimed to validate the accidental discovery by investigating the effect on simple obesity of the topical application of TAT-SOD to acupoints in comparison with acupuncture. 90 subjects were divided into 3 groups for 12-week treatments. Regular hospital acupuncture treatment was given to Acupuncture Group 3 times a week. TAT-SOD Group were instructed first to locate acupoints and apply 0.1ml of 5000u SOD/ml TAT-SOD cream in an area of 1cm2 to each of the same set of acupoints, which they then conducted at home three times daily. Placebo Group applied the vehicle cream the same manner as TAT-SOD Group. Both TAT-SOD and acupuncture treatments decreased adiposity with overall clinical effective rates of 60.0% and 76.7%, respectively. The placebo group showed no improvement. The results validate that the enzymatic removal of the intracellular superoxide at acupoints could generate acupuncture-like effects, and indicate a possibility of the new method as a simple substitute to acupuncture and an insight of superoxide modulation along meridians for acupuncture mechanism. [Copyright &y& Elsevier]

Abstract: Aims: The intracellular superoxide anion has been shown to be involved in brain injury. TAT-Superoxide dismutase (TAT-SOD) can be transduced across the cell membrane to scavenge superoxide. This protein''s unique properties make it a promising therapeutic candidate to attenuate cerebral damage. In this study, we sought further the understanding of the fusion protein''s cerebral protective effects and the mechanism which is exerted in these effects. Main methods: Male Sprague Dawley rats (n=100, 230±20g) were divided randomly into five experimental groups: a sham group, a cerebral Ischemia/Reperfusion (I/R) group treated with saline (20ml/Kg, i.p.), and three cerebral I/R groups treated with TAT-SOD (25KU/ml/Kg, i.p.) at either 2h before I/R, 2h after I/R or 4h after I/R. Cerebral I/R injury was facilitated by inducing ischemia for two hours followed by 24h reperfusion. The levels of SOD, Malondialdehyde (MDA), and ATPase in cerebral tissues were determined. The apoptotic indexes were evaluated, and apoptosis genes were analyzed immunohistochemically. Key findings: TAT-SOD treatment significantly increased cerebral SOD and ATPase activities, decreased MDA content, and remarkably reduced apoptosis indexes. TAT-SOD treatments 2h before or after I/R significantly reduced caspase-3 and bax proteins and boosted bcl-2 protein, while the treatment at 4h after I/R showed no influence on the three proteins. Significance: TAT-SOD treatment effectively enhanced cerebral antioxidant ability, reduced lipid peroxidation, preserved mitochondrial ATPase and thus inhibited nerve cell apoptosis. The effective treatment window extended from 2h before to 2h after I/R. [Copyright &y& Elsevier]

Not only enjoyed as delicacy, soups of vegetables, fish or meat are also served as folk remedies in many cultures. The formation of nanostructures was observed both in the hepato-protective freshwater clam soup and the anti-diabetic bitter melon soup. It was in accompany with either the migration of clam compositions into the soup or the progression of Maillard reaction in bitter melon. The biochemical compositions, bioactivities and colloidal characteristics of those nano-particles were preliminarily investigated. It implies that the nanostructures may probably be the functioning unit, and provide a novel perspective to understanding the complicated food system. [ABSTRACT FROM AUTHOR]

Abstract: A novel lectin with a molecular mass of 22.5kDa, designated as AOL, has been isolated from fresh rhizome of Alisma orientale (Sam.) Juzep. The purification procedure involved ammonium sulfate precipitation, affinity chromatography on Affi-gel blue gel and gel filtration chromatography on Sephacryl S200. AOL was a monomer with intrachain disulfide bond; its isoelectric point was estimated to be 5.6. The lectin could be stained in red by periodic acid-Schiff (PAS) reagent, it consisted of 93.7% protein and 6.3% sugar. N-terminal amino acid sequence of AOL was determined to be EAVVDTNGDLIHTGSIH. AOL exhibited hemagglutinating activity in human erythrocytes. The hemagglutinating activity was mostly preserved up to 50°C and was indiscernible when the temperature above 70°C. It was stable over the pH range 2–11. Among the carbohydrates tested, l-arabinose, mannitol, d-xylose and l-rhamnose were capable of inhibiting the hemagglutinating activity. AOL was a metal dependent protein, metallic compounds including LiCl, FeCl3, MnCl2 and K2Cr2O7 inhibited the activity whereas MgCl2, ZnCl2, BaCl2, CuCl2 and CaCl2 did not affect its activity, which means all these metallic compounds cannot promote the activity of AOL. Proliferation of tumor cells HeLa cells was inhibited by AOL with an IC50 of 7.3μM, HepG2 cells and the normal cells MDCK was just slightly affected even at the concentration of 40μM. AOL did not exhibit antifungal activity. [Copyright &y& Elsevier]

plant lysozyme exhibiting antifungal activity and with a molecular mass of 20.1 kDa in SDS-polyacrylamide gel electrophoresis was isolated from Momordica charantia L using a procedure that involved aqueous extraction, vacuum freeze-drying of extraction, and ion exchange chromatography on high-performance liquid chromatography on Source Q and POROS 50 HS. Its N-terminal sequence was determined to be Q-L-C-E-L-A-A-C-M-K-R-H-G-L-D, showing relatively high homology (about 80%) with that of hen egg white lysozyme. Its pI was estimated to be 9.9. The lysozyme exhibited a pH optimum at pH 5.5 and a temperature optimum at 50 °C. Moreover, the lysozyme exerted an antifungal action toward Mucorracem osus and Rhizoctonia solani, in addition to an antibacterial action against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]