In vitro studies on the interactions of blood lipid level-related biological molecules with gallic acid and tannic acid

Encapsulation of roast beef flavor by soy protein isolate/chitosan complex Pickering emulsions to improve its releasing properties during the processing of plant-based meat analogues

During the production of plant-based meat analogues (PBMA), a significant loss of flavor characteristic compounds in meat-flavor essences could be observed. Pickering emulsion-based encapsulation is an effective method to improve their stability. Therefore, a soy protein isolate (SPI)/chitosan (CS) complex Pickering emulsion was fabricated to encapsulate roast beef flavor (RBF) and further applied in the processing of PBMA. Our results indicated that the network structure of emulsions was dominated by elasticity, while hydrogen and covalent bonding interactions played important roles in the encapsulation process. The release rate of flavor compounds gradually increased with the increase of pH value, glutamine transaminase, NaCl content, heating temperature or heating time, while encapsulation significantly reduced the loss of characteristic aroma compounds. In addition, the releasing characteristics of aroma compounds and textural properties of PBMA were greatly improved by treating with RBF-loaded emulsions. Consequently, the emulsions were promising to improve the flavor quality of PBMA.

Tannic acid- and N-acetylcysteine-chitosan-modified magnetic nanoparticles reduce hepatic oxidative stress in prediabetic rats

Magnetic nanoparticles (MNPs) modified with tannic acid (TA) have shown remarkable success as an antioxidant and antimicrobial therapeutic agent. Herein, we report a synthetic procedure for the preparation of silica-coated MNPs modified with N-acetylcysteine-modified chitosan and TA. This was achieved by free-radical grafting of NAC onto chitosan (CS), a layer-by-layer technique for modifying negatively charged MNP@SiO2 nanoparticles with positively charged CS-NAC, and crosslinking CS with TA. The antioxidant and metabolic effects of MNP@SiO2-CS-NAC and MNP@SiO2-CS-NAC-TA nanoparticles were tested in a model of prediabetic rats with hepatic steatosis, the hereditary hypertriglyceridemic rats (HHTg). The particles exhibited significant antioxidant properties in the liver, increasing the activity of the antioxidant enzymes superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx), decreasing the concentration of the lipoperoxidation product malondialdehyde (MDA), and improving the antioxidant status determined as the ratio of reduced to oxidized glutathione; in particular, TA increased some antioxidant parameters. MNPs carrying antioxidants such as NAC and TA could thus represent a promising therapeutic agent for the treatment of various diseases accompanied by increased oxidative stress.

Surface Modification of Okara Cellulose Crystals with Phenolic Acids to Prepare Multifunction Emulsifier with Antioxidant Capacity and Lipolysis Retardation Effect

Emulsion-based foods are widely consumed, and their characteristics involving colloidal and oxidative stabilities should be considered. The fabrication of the interfaces by selecting the emulsifier may improve stability and trigger lipolysis, thereby reducing energy uptake from the emulsified food. The present work aimed to develop Okara cellulose crystals (OCs) as a multifunction emulsifier to preserve the physical and chemical stability of a Pickering emulsion via surface modification with phenolic acids. The modification of OC was performed by grafting with the selected phenolics to produce OC-gallic acid (OC-G) and OC-tannic acid (OC-T) complexes. There was a higher phenolic loading efficiency when the OC reacted with gallic acid (ca. 70%) than with tannic acid (ca. 50%). This trend was concomitant with better antioxidant activity of the OC-G than OC-T. Surface modification based on grafting with phenolic acids improved capability of the OC to enhance both the colloidal and oxidative stability of the emulsion. In addition, the cellulosic materials had a retardation effect on the in vitro lipolysis compared to a protein-stabilized emulsion. Surface modification by grafting with phenolic acids successfully provided OC as an innovative emulsifier to promote physico-chemical stability and lower lipolysis of the emulsion.

Self-assembled condensed tannins supramolecular system can adsorb cholesterol micelles to promote cholesterol excretion

In this study, the cholesterol (CH)-lowering behavioral mechanisms and drivers of condensed tannins (CTs) were revealed using a molecular aggregation theoretical model combined with in vitro experiments, as well as the CH-lowering effects of CTs validated based on animal experiments. Theoretical model results indicated that CTs can spontaneously aggregate to form supramolecular systems, can break CH micelles and form larger aggregates, a behavior driven by van der Waals forces and hydrogen bonds; DLS and TEM results confirmed that the presence of CH leads to a larger particle size of CTs and the formation of large aggregates; thermodynamic analysis and ITC revealed that the adsorption of CH by CTs is a spontaneous reaction driven by hydrogen bonds and hydrophobic forces; Animal experiments and fecal biochemical parameters further confirmed that the intake of CTs can reduce CH absorption and promotes CH excretion. Overall, this study reveals the CH-lowering behavioral mechanism of CTs from the perspective of molecular aggregation behavior.

Extraction of a Triterpene Solution and Evaluation of the Hypolipidemic Efficacy of the Pleurotus tuber-regium (Fr.) Sing Sclerotium

The total triterpenes in edible mushrooms have high medicinal value, and the sclerotium has various biological activities, such as the regulation of blood pressure and blood glucose. In this study, the total triterpenes of the Pleurotus tuber-regium (Fr.) Sing Sclerotium (PTRSS) were extracted, and their hypolipidemic effects were also investigated. The infrared spectra showed that the total triterpenes were consistent with the characteristic structures of the total triterpenes before and after purification. The binding abilities of total triterpenes to sodium glycocholate, sodium taurocholate, and sodium cholate were investigated, and all of them had a good binding ability to cholate. In vivo experiments showed that zebrafish tolerated the total triterpenes from the mushroom nuclei at a maximum concentration of 500 µg/mL. A correlation analysis showed that the total triterpenes from the mushroom nuclei reduced the lipid accumulation in zebrafish induced by a high-fat diet, and the lipid-lowering effect showed a correlation with dose.

Pharmacological effects and mechanisms of tannic acid

In recent years, increasing attention has been paid to the pharmacological efficacy of tannins. Tannic acid (TA), the simplest hydrolysable tannin that has been approved by the FDA as a safe food additive, is one of the most important components of these traditional medicines. Studies have shown that TA displays a wide range of pharmacological activities, such as anti-inflammatory, neuroprotective, antitumor, cardioprotective, and anti-pathogenic effects. Here, we summarize the known pharmacological effects and associated mechanisms of TA. We focus on the effect and mechanism of TA in various animal models of inflammatory disease and organ, brain, and cardiovascular injury. Moreover, we discuss the possible molecular targets and signaling pathways of TA, in addition to the pharmacological effects of TA-based nanoparticles and TA in combination with chemotherapeutic drugs.

Preparation and Characterization of Beads of Sodium Alginate/Carboxymethyl Chitosan/Cellulose Nanofiber Containing Porous Starch Embedded with Gallic Acid: An In Vitro Simulation Delivery Study

In this study, a system was designed that can encapsulate and deliver gallic acid (GA), which was composed of polysaccharide polymers based on sodium alginate (SA), carboxymethyl chitosan (CCT), and cellulose nanofibers (CN) and was assisted by porous starch. The compositions were characterized by rheology and zeta potentials, and the results showed that the materials used in this study could effectively guarantee the stability of the system. The morphology and chemical structure of the beads were characterized by SEM and FT-IR, the results indicated that the addition of CCT could effectively reduce the cracks and pores on the surface of the beads, which was beneficial to the encapsulation and delivery of GA. Moreover, the results of the swelling rate, release tests, and antioxidant tests also proved the effectiveness of the system. The pH response effect of SA/CN/CCT (SCC) beads and the protection of GA were superior, and the release rate of GA in simulated gastric fluid (SGF) was only 6.95%, while SA and SA/CN (SCN) beads reached 57.94% and 78.49%, respectively. In conclusion, the interpenetrating network polymers constructed by SA, CCT, and CN, which, combined with porous starch as a coating layer, can achieve the embedding and the delivery of GA.

Biomedical applications of tannic acid

Tannic Acid (TA) is a naturally occurring antioxidant polyphenol that has gained popularity over the past decade in the field of biomedical research for its unique biochemical properties. Tannic acid, typically extracted from oak tree galls, has been used in many important historical applications. TA is a key component in vegetable tanning of leather, iron gall ink, red wines, and as a traditional medicine to treat a variety of maladies. The basis of TA utility is derived from its many hydroxyl groups and its affinity for forming hydrogen bonds with proteins and other biomolecules. Today, the study of TA has led to the development of many new pharmaceutical and biomedical applications. TA has been shown to reduce inflammation as an antioxidant, act as an antibiotic in common pathogenic bacterium, and induce apoptosis in several cancer types. TA has also displayed antiviral and antifungal activity. At certain concentrations, TA can be used to treat gastrointestinal disorders such as hemorrhoids and diarrhea, severe burns, and protect against neurodegenerative diseases. TA has also been utilized in biomaterials research as a natural crosslinking agent to improve mechanical properties of natural and synthetic hydrogels and polymers, while also imparting anti-inflammatory, antibacterial, and anticancer activity to the materials. TA has also been used to develop thin film coatings and nanoparticles for drug delivery. In all, TA is fascinating molecule with a wide variety of potential uses in pharmaceuticals, biomaterials applications, and drug delivery strategies.

Dietary Intake of Hydrolyzable Tannins and Condensed Tannins to Regulate Lipid Metabolism

Lipid metabolism disorder is a multifactor issue, which contributes to several serious health consequences, such as obesity, hyperlipidemia, atherosclerosis diabetes, non-alcoholic fatty liver etc. Tannins, applied as natural derived plant, are commonly used in the study of lipid metabolism disease with excellent safety and effectiveness, while producing less toxic and side effects. Meanwhile, recognition of the significance of dietary tannins in lipid metabolism disease prevention has increased. As suggested by existing evidence, dietary tannins can reduce lipid accumulation, block adipocyte differentiation, enhance antioxidant capacity, increase the content of short-chain fatty acids, and lower blood lipid levels, thus alleviating lipid metabolism disorder. This study is purposed to sum up and analyze plenty of documents on tannins, so as to provide the information required to assess the lipid metabolism of tannins.

Spectroscopic and computational studies on the binding interaction between gallic acid and Pin1

Gallic acid (GA) is a natural ingredient in functional foods, which has various health-promoting and antitumour effects. Peptidyl-prolyl cis/trans isomerase Pin1 plays an important role in preventing the development of some malignant tumours. However, whether there was an interaction between Pin1 and GA remains unknown. In this work, the binding information of GA and Pin1 was investigated systematically using multiple spectral and computational methods. GA bound to Pin1 directly with moderate binding affinity in the order of 10⁴  mol/L, therefore decreasing the activity of Pin1. Also, the binding process of GA to Pin1 was driven through weak van der Waals forces, hydrogen bonds, and electrostatic forces. In addition, the important residues Lys63, Arg68, and Arg69 played a significant role in maintaining the binding stability between Pin1 and GA. Interestingly, GA reduced the activity of Pin1 by affecting its conformational characteristics. Our present work showed that GA binds to Pin1 and inhibits its activity, affecting its structural and functional properties, which may contribute to the therapy of Pin1-related diseases.

Hypolipidemic, anti-inflammatory, and anti-atherosclerotic effects of tea before and after microbial fermentation

BACKGROUND

Microbial fermentation significantly affects the flavor and efficacy of tea. It is generally believed that fermented tea is more effective in lowering lipids, while unfermented tea can more effectively inhibit inflammation. However, there is not sufficient evidence to support this claim. To systematically compare the hypolipidemic, anti-inflammatory, and anti-atherosclerotic effects of tea before and after microbial fermentation, hyperlipidemic rats and inflammatory injury cells were treated with Monascus purpureus-fermented pu-erh tea water extract (MPT) and sun-dried green tea water extract (SGT), respectively.

RESULTS

MPT, with higher levels of theabrownins, flavonoids, gallic acid (GA), and lovastatin, was more effective in reducing serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and inflammatory cytokines (TNF-α, IL-1β, and IL-6), while SGT, with higher levels of tea polyphenols, amino acids, (-)-epigallocatechin gallate (EGCG), and theaflavins, was more effective in increasing serum high-density lipoprotein cholesterol (HDL-C) in hyperlipidemic rats. The foam cells on the arterial wall of the rats in the MPT group were visibly less, and the thrombosis time was longer than that in the SGT group. Cell experiments showed that MPT was more effective in protecting endothelial cells from damage than SGT.

CONCLUSION

Surprisingly, Monascus purpureus-fermented pu-erh tea not only had better hypolipidemic and anti-atherosclerotic effects than its raw material (sun-dried green tea), but also was superior in anti-inflammatory effects to the latter, which was possibly attributable to the great changes in functional ingredients during microbial fermentation.

Preparation, characterization and in vitro hypoglycemic activity of banana condensed tannin-inulin conjugate

To enhance the hypoglycemic effects of inulin, banana condensed tannins (BCT) were grafted onto inulin via a free radical method to synthesize the novel BCT grafted inulin (BCT-g-inulin) complex. Spectroscopic methods, XRD, TGA, 1H NMR, GPC and morphology analyses were utilized to characterize the structural properties of the BCT-g-inulin complex, and our results confirmed the conjugation of BCT and inulin. The conjugation possibly occurred between the hydroxyl group attached at the C6 position of inulin and the C6/C8 position of flavon-3-ol units of BCT. The grafting ratio and grafting efficiency of the BCT-g-inulin complex were 357.54 ± 2.98 g kg-1 complex and 74.57 ± 1.44%, respectively. The data of the antioxidant assays indicated that the BCT-g-inulin complex showed a significantly higher antioxidant activity than native inulin. Also, the grafting reaction remarkably improved the in vitro anti-diabetic activity of inulin. The glucose adsorption capacity and glucose dialysis retardation index of the BCT-g-inulin complex were remarkably higher than those of inulin, while the BCT-g-inulin complex showed much stronger inhibitory effects against α-amylase and α-glucosidase compared with inulin. Notably, the inhibition of both α-amylase and α-glucosidase by the BCT-g-inulin complex occurred through mixed-competitive mode. On the basis of fluorescence spectroscopy, the fluorescence of α-amylase and α-glucosidase could be quenched by the BCT-g-inulin complex through a static quenching mechanism. Hence, the BCT-g-inulin complex might have the potential to be developed as an effective anti-diabetic agent.

Cinnamomum burmannii (Nees & T. Nees) Blume and Eleutherine palmifolia (L.) Merr. extract combination ameliorate lipid profile and heart oxidative stress in hyperlipidemic mice

Background and Aim:

Hyperlipidemia is an important risk factor for cardiovascular disease. The use of statins has adverse side effects that result in oxidative stress disorders. The objective of this study was to investigate the antihyperlipidemic effect of a combination of Cinnamomum burmannii and Eleutherine palmifolia extract in high-fat diet (HFD)-induced hyperlipidemia mice.

Materials and Methods:

Mice were divided into eight groups (n=4): Control group or healthy mice (normal), HFD-induced hyperlipidemic mice without any treatment (CE0), HFD-induced hyperlipidemic mice treated with 3.6 mg/kg body weight (BW) atorvastatin (atorvastatin), and HFD-induced hyperlipidemic mice treated with a combination of C. burmannii and E. palmifolia in the following ratios: 300:0 (C300), 225:75 (C225), 150:150 (CE150), 75:225 (E225), and 0:300 (E300). Mice were fed a HFD for 4 months to induce hyperlipidemia. Total cholesterol, cholesterol oxidase-peroxidase aminophenazone (CHOD-PAP), triglyceride-glycerine, and fat serum were analyzed with colorimetric method. The measurement of superoxide dismutase was done with the xanthine oxidase method and malondialdehyde measurement was done with the thiobarbituric acid method.

Results:

Results showed an increase in antihyperlipidemic characteristics as the concentration of E. palmifolia extract (p<0.05) increased. Duncan’s multiple range test also showed an increase in anti-stress oxidation as the concentration of C. burmannii extract (p<0.05) increased.

Conclusion:

The E225 group showed the most potential as a safe, antihyperlipidemic agent characterized by improvement in lipid profile and antioxidant balance.

Cinnamomum burmannii (Nees & T. Nees) Blume and Eleutherine palmifolia (L.) Merr. extract combination ameliorate lipid profile and heart oxidative stress in hyperlipidemic mice

Background and Aim: Hyperlipidemia is an important risk factor for cardiovascular disease. The use of statins has adverse side effects that result in oxidative stress disorders. The objective of this study was to investigate the antihyperlipidemic effect of a combination of Cinnamomum burmannii and Eleutherine palmifolia extract in high-fat diet (HFD)-induced hyperlipidemia mice. Materials and Methods: Mice were divided into eight groups (n=4): Control group or healthy mice (normal), HFD-induced hyperlipidemic mice without any treatment (CE0), HFD-induced hyperlipidemic mice treated with 3.6 mg/kg body weight (BW) atorvastatin (atorvastatin), and HFD-induced hyperlipidemic mice treated with a combination of C. burmannii and E. palmifolia in the following ratios: 300:0 (C300), 225:75 (C225), 150:150 (CE150), 75:225 (E225), and 0:300 (E300). Mice were fed a HFD for 4 months to induce hyperlipidemia. Total cholesterol, cholesterol oxidase-peroxidase aminophenazone (CHOD-PAP), triglyceride-glycerine, and fat serum were analyzed with colorimetric method. The measurement of superoxide dismutase was done with the xanthine oxidase method and malondialdehyde measurement was done with the thiobarbituric acid method. Results: Results showed an increase in antihyperlipidemic characteristics as the concentration of E. palmifolia extract (p<0.05) increased. Duncan's multiple range test also showed an increase in anti-stress oxidation as the concentration of C. burmannii extract (p<0.05) increased. Conclusion: The E225 group showed the most potential as a safe, antihyperlipidemic agent characterized by improvement in lipid profile and antioxidant balance.